Progress towards mdstr elimination

include/grpc/slice.h

@@ -130,6 +130,8 @@ GPRAPI int grpc_slice_buf_cmp(grpc_slice a, const void *b, size_t blen);
 
 GPRAPI int grpc_slice_buf_start_eq(grpc_slice a, const void *b, size_t blen);
 
+GPRAPI int grpc_slice_rchr(grpc_slice s, char c);
+
 GPRAPI uint32_t grpc_slice_hash(grpc_slice s);
 
 #ifdef __cplusplus

src/core/ext/transport/chttp2/transport/chttp2_plugin.c

@@ -37,8 +37,6 @@
 #include "src/core/lib/transport/metadata.h"
 
 void grpc_chttp2_plugin_init(void) {
-  grpc_chttp2_base64_encode_and_huffman_compress =
-      grpc_chttp2_base64_encode_and_huffman_compress_impl;
   grpc_register_tracer("http", &grpc_http_trace);
   grpc_register_tracer("flowctl", &grpc_flowctl_trace);
 }

src/core/lib/transport/method_config.c

@@ -40,7 +40,9 @@
 #include <grpc/support/time.h>
 
 #include "src/core/lib/slice/slice_hash_table.h"
+#include "src/core/lib/slice/slice_internal.h"
 #include "src/core/lib/transport/metadata.h"
+#include "src/core/lib/transport/static_metadata.h"
 
 //
 // grpc_method_config
@@ -48,37 +50,37 @@
 
 // bool vtable
 
-static void* bool_copy(void* valuep) {
-  bool value = *(bool*)valuep;
-  bool* new_value = gpr_malloc(sizeof(bool));
+static void *bool_copy(void *valuep) {
+  bool value = *(bool *)valuep;
+  bool *new_value = gpr_malloc(sizeof(bool));
   *new_value = value;
   return new_value;
 }
 
-static int bool_cmp(void* v1, void* v2) {
-  bool b1 = *(bool*)v1;
-  bool b2 = *(bool*)v2;
+static int bool_cmp(void *v1, void *v2) {
+  bool b1 = *(bool *)v1;
+  bool b2 = *(bool *)v2;
   if (!b1 && b2) return -1;
   if (b1 && !b2) return 1;
   return 0;
 }
 
-static void free_mem(grpc_exec_ctx* exec_ctx, void* p) { gpr_free(p); }
+static void free_mem(grpc_exec_ctx *exec_ctx, void *p) { gpr_free(p); }
 
 static grpc_slice_hash_table_vtable bool_vtable = {free_mem, bool_copy,
                                                    bool_cmp};
 
 // timespec vtable
 
-static void* timespec_copy(void* valuep) {
-  gpr_timespec value = *(gpr_timespec*)valuep;
-  gpr_timespec* new_value = gpr_malloc(sizeof(gpr_timespec));
+static void *timespec_copy(void *valuep) {
+  gpr_timespec value = *(gpr_timespec *)valuep;
+  gpr_timespec *new_value = gpr_malloc(sizeof(gpr_timespec));
   *new_value = value;
   return new_value;
 }
 
-static int timespec_cmp(void* v1, void* v2) {
-  return gpr_time_cmp(*(gpr_timespec*)v1, *(gpr_timespec*)v2);
+static int timespec_cmp(void *v1, void *v2) {
+  return gpr_time_cmp(*(gpr_timespec *)v1, *(gpr_timespec *)v2);
 }
 
 static grpc_slice_hash_table_vtable timespec_vtable = {free_mem, timespec_copy,
@@ -86,16 +88,16 @@ static grpc_slice_hash_table_vtable timespec_vtable = {free_mem, timespec_copy,
 
 // int32 vtable
 
-static void* int32_copy(void* valuep) {
-  int32_t value = *(int32_t*)valuep;
-  int32_t* new_value = gpr_malloc(sizeof(int32_t));
+static void *int32_copy(void *valuep) {
+  int32_t value = *(int32_t *)valuep;
+  int32_t *new_value = gpr_malloc(sizeof(int32_t));
   *new_value = value;
   return new_value;
 }
 
-static int int32_cmp(void* v1, void* v2) {
-  int32_t i1 = *(int32_t*)v1;
-  int32_t i2 = *(int32_t*)v2;
+static int int32_cmp(void *v1, void *v2) {
+  int32_t i1 = *(int32_t *)v1;
+  int32_t i2 = *(int32_t *)v2;
   if (i1 < i2) return -1;
   if (i1 > i2) return 1;
   return 0;
@@ -104,57 +106,37 @@ static int int32_cmp(void* v1, void* v2) {
 static grpc_slice_hash_table_vtable int32_vtable = {free_mem, int32_copy,
                                                     int32_cmp};
 
-// Hash table keys.
-#define GRPC_METHOD_CONFIG_WAIT_FOR_READY "grpc.wait_for_ready"  // bool
-#define GRPC_METHOD_CONFIG_TIMEOUT "grpc.timeout"                // gpr_timespec
-#define GRPC_METHOD_CONFIG_MAX_REQUEST_MESSAGE_BYTES \
-  "grpc.max_request_message_bytes"  // int32
-#define GRPC_METHOD_CONFIG_MAX_RESPONSE_MESSAGE_BYTES \
-  "grpc.max_response_message_bytes"  // int32
-
 struct grpc_method_config {
-  grpc_slice_hash_table* table;
-  grpc_slice  wait_for_ready_key;
-  grpc_slice  timeout_key;
-  grpc_slice  max_request_message_bytes_key;
-  grpc_slice  max_response_message_bytes_key;
+  grpc_slice_hash_table *table;
 };
 
-grpc_method_config* grpc_method_config_create(
-    bool* wait_for_ready, gpr_timespec* timeout,
-    int32_t* max_request_message_bytes, int32_t* max_response_message_bytes) {
-  grpc_method_config* method_config = gpr_malloc(sizeof(grpc_method_config));
+grpc_method_config *grpc_method_config_create(
+    bool *wait_for_ready, gpr_timespec *timeout,
+    int32_t *max_request_message_bytes, int32_t *max_response_message_bytes) {
+  grpc_method_config *method_config = gpr_malloc(sizeof(grpc_method_config));
   memset(method_config, 0, sizeof(grpc_method_config));
-  method_config->wait_for_ready_key =
-      grpc_mdstr_from_string(GRPC_METHOD_CONFIG_WAIT_FOR_READY);
-  method_config->timeout_key =
-      grpc_mdstr_from_string(GRPC_METHOD_CONFIG_TIMEOUT);
-  method_config->max_request_message_bytes_key =
-      grpc_mdstr_from_string(GRPC_METHOD_CONFIG_MAX_REQUEST_MESSAGE_BYTES);
-  method_config->max_response_message_bytes_key =
-      grpc_mdstr_from_string(GRPC_METHOD_CONFIG_MAX_RESPONSE_MESSAGE_BYTES);
   grpc_slice_hash_table_entry entries[4];
   size_t num_entries = 0;
   if (wait_for_ready != NULL) {
-    entries[num_entries].key = method_config->wait_for_ready_key;
+    entries[num_entries].key = GRPC_MDSTR_GRPC_DOT_WAIT_FOR_READY;
     entries[num_entries].value = wait_for_ready;
     entries[num_entries].vtable = &bool_vtable;
     ++num_entries;
   }
   if (timeout != NULL) {
-    entries[num_entries].key = method_config->timeout_key;
+    entries[num_entries].key = GRPC_MDSTR_GRPC_DOT_TIMEOUT;
     entries[num_entries].value = timeout;
     entries[num_entries].vtable = &timespec_vtable;
     ++num_entries;
   }
   if (max_request_message_bytes != NULL) {
-    entries[num_entries].key = method_config->max_request_message_bytes_key;
+    entries[num_entries].key = GRPC_MDSTR_GRPC_DOT_MAX_REQUEST_MESSAGE_BYTES;
     entries[num_entries].value = max_request_message_bytes;
     entries[num_entries].vtable = &int32_vtable;
     ++num_entries;
   }
   if (max_response_message_bytes != NULL) {
-    entries[num_entries].key = method_config->max_response_message_bytes_key;
+    entries[num_entries].key = GRPC_MDSTR_GRPC_DOT_MAX_RESPONSE_MESSAGE_BYTES;
     entries[num_entries].value = max_response_message_bytes;
     entries[num_entries].vtable = &int32_vtable;
     ++num_entries;
@@ -163,137 +145,129 @@ grpc_method_config* grpc_method_config_create(
   return method_config;
 }
 
-grpc_method_config* grpc_method_config_ref(grpc_method_config* method_config) {
+grpc_method_config *grpc_method_config_ref(grpc_method_config *method_config) {
   grpc_slice_hash_table_ref(method_config->table);
   return method_config;
 }
 
-void grpc_method_config_unref(grpc_exec_ctx* exec_ctx,
-                              grpc_method_config* method_config) {
+void grpc_method_config_unref(grpc_exec_ctx *exec_ctx,
+                              grpc_method_config *method_config) {
   if (grpc_slice_hash_table_unref(exec_ctx, method_config->table)) {
-    GRPC_MDSTR_UNREF(exec_ctx, method_config->wait_for_ready_key);
-    GRPC_MDSTR_UNREF(exec_ctx, method_config->timeout_key);
-    GRPC_MDSTR_UNREF(exec_ctx, method_config->max_request_message_bytes_key);
-    GRPC_MDSTR_UNREF(exec_ctx, method_config->max_response_message_bytes_key);
     gpr_free(method_config);
   }
 }
 
-int grpc_method_config_cmp(const grpc_method_config* method_config1,
-                           const grpc_method_config* method_config2) {
+int grpc_method_config_cmp(const grpc_method_config *method_config1,
+                           const grpc_method_config *method_config2) {
   return grpc_slice_hash_table_cmp(method_config1->table,
                                    method_config2->table);
 }
 
-const bool* grpc_method_config_get_wait_for_ready(
-    const grpc_method_config* method_config) {
+const bool *grpc_method_config_get_wait_for_ready(
+    const grpc_method_config *method_config) {
   return grpc_slice_hash_table_get(method_config->table,
-                                   method_config->wait_for_ready_key);
+                                   GRPC_MDSTR_GRPC_DOT_WAIT_FOR_READY);
 }
 
-const gpr_timespec* grpc_method_config_get_timeout(
-    const grpc_method_config* method_config) {
+const gpr_timespec *grpc_method_config_get_timeout(
+    const grpc_method_config *method_config) {
   return grpc_slice_hash_table_get(method_config->table,
-                                   method_config->timeout_key);
+                                   GRPC_MDSTR_GRPC_DOT_TIMEOUT);
 }
 
-const int32_t* grpc_method_config_get_max_request_message_bytes(
-    const grpc_method_config* method_config) {
+const int32_t *grpc_method_config_get_max_request_message_bytes(
+    const grpc_method_config *method_config) {
   return grpc_slice_hash_table_get(
-      method_config->table, method_config->max_request_message_bytes_key);
+      method_config->table, GRPC_MDSTR_GRPC_DOT_MAX_REQUEST_MESSAGE_BYTES);
 }
 
-const int32_t* grpc_method_config_get_max_response_message_bytes(
-    const grpc_method_config* method_config) {
+const int32_t *grpc_method_config_get_max_response_message_bytes(
+    const grpc_method_config *method_config) {
   return grpc_slice_hash_table_get(
-      method_config->table, method_config->max_response_message_bytes_key);
+      method_config->table, GRPC_MDSTR_GRPC_DOT_MAX_RESPONSE_MESSAGE_BYTES);
 }
 
 //
 // grpc_method_config_table
 //
 
-static void method_config_unref(grpc_exec_ctx* exec_ctx, void* valuep) {
+static void method_config_unref(grpc_exec_ctx *exec_ctx, void *valuep) {
   grpc_method_config_unref(exec_ctx, valuep);
 }
 
-static void* method_config_ref(void* valuep) {
+static void *method_config_ref(void *valuep) {
   return grpc_method_config_ref(valuep);
 }
 
-static int method_config_cmp(void* valuep1, void* valuep2) {
+static int method_config_cmp(void *valuep1, void *valuep2) {
   return grpc_method_config_cmp(valuep1, valuep2);
 }
 
 static const grpc_slice_hash_table_vtable method_config_table_vtable = {
     method_config_unref, method_config_ref, method_config_cmp};
 
-grpc_method_config_table* grpc_method_config_table_create(
-    size_t num_entries, grpc_method_config_table_entry* entries) {
-  grpc_slice_hash_table_entry* hash_table_entries =
+grpc_method_config_table *grpc_method_config_table_create(
+    size_t num_entries, grpc_method_config_table_entry *entries) {
+  grpc_slice_hash_table_entry *hash_table_entries =
       gpr_malloc(sizeof(grpc_slice_hash_table_entry) * num_entries);
   for (size_t i = 0; i < num_entries; ++i) {
     hash_table_entries[i].key = entries[i].method_name;
     hash_table_entries[i].value = entries[i].method_config;
     hash_table_entries[i].vtable = &method_config_table_vtable;
   }
-  grpc_method_config_table* method_config_table =
+  grpc_method_config_table *method_config_table =
       grpc_slice_hash_table_create(num_entries, hash_table_entries);
   gpr_free(hash_table_entries);
   return method_config_table;
 }
 
-grpc_method_config_table* grpc_method_config_table_ref(
-    grpc_method_config_table* table) {
+grpc_method_config_table *grpc_method_config_table_ref(
+    grpc_method_config_table *table) {
   return grpc_slice_hash_table_ref(table);
 }
 
-void grpc_method_config_table_unref(grpc_exec_ctx* exec_ctx,
-                                    grpc_method_config_table* table) {
+void grpc_method_config_table_unref(grpc_exec_ctx *exec_ctx,
+                                    grpc_method_config_table *table) {
   grpc_slice_hash_table_unref(exec_ctx, table);
 }
 
-int grpc_method_config_table_cmp(const grpc_method_config_table* table1,
-                                 const grpc_method_config_table* table2) {
+int grpc_method_config_table_cmp(const grpc_method_config_table *table1,
+                                 const grpc_method_config_table *table2) {
   return grpc_slice_hash_table_cmp(table1, table2);
 }
 
-void* grpc_method_config_table_get(grpc_exec_ctx* exec_ctx,
-                                   const grpc_slice_hash_table* table,
-                                   const grpc_slice  path) {
-  void* value = grpc_slice_hash_table_get(table, path);
+void *grpc_method_config_table_get(grpc_exec_ctx *exec_ctx,
+                                   const grpc_slice_hash_table *table,
+                                   const grpc_slice path) {
+  void *value = grpc_slice_hash_table_get(table, path);
   // If we didn't find a match for the path, try looking for a wildcard
   // entry (i.e., change "/service/method" to "/service/*").
   if (value == NULL) {
-    const char* path_str = grpc_mdstr_as_c_string(path);
-    const char* sep = strrchr(path_str, '/') + 1;
-    const size_t len = (size_t)(sep - path_str);
-    char* buf = gpr_malloc(len + 2);  // '*' and NUL
-    memcpy(buf, path_str, len);
-    buf[len] = '*';
-    buf[len + 1] = '\0';
-    grpc_slice  wildcard_path = grpc_mdstr_from_string(buf);
-    gpr_free(buf);
-    value = grpc_slice_hash_table_get(table, wildcard_path);
-    GRPC_MDSTR_UNREF(exec_ctx, wildcard_path);
+    int sep_pos = grpc_slice_rchr(path, '/') + 1;
+    grpc_slice search = grpc_slice_malloc((size_t)(sep_pos + 1));
+    memcpy(GRPC_SLICE_START_PTR(search), GRPC_SLICE_START_PTR(path),
+           (size_t)sep_pos);
+    GRPC_SLICE_START_PTR(search)[sep_pos] = '*';
+    value = grpc_slice_hash_table_get(table, search);
+    grpc_slice_unref_internal(exec_ctx, search);
   }
   return value;
 }
 
-static void* copy_arg(void* p) { return grpc_method_config_table_ref(p); }
+static void *copy_arg(void *p) { return grpc_method_config_table_ref(p); }
 
-static void destroy_arg(grpc_exec_ctx* exec_ctx, void* p) {
+static void destroy_arg(grpc_exec_ctx *exec_ctx, void *p) {
   grpc_method_config_table_unref(exec_ctx, p);
 }
 
-static int cmp_arg(void* p1, void* p2) {
+static int cmp_arg(void *p1, void *p2) {
   return grpc_method_config_table_cmp(p1, p2);
 }
 
 static grpc_arg_pointer_vtable arg_vtable = {copy_arg, destroy_arg, cmp_arg};
 
 grpc_arg grpc_method_config_table_create_channel_arg(
-    grpc_method_config_table* table) {
+    grpc_method_config_table *table) {
   grpc_arg arg;
   arg.type = GRPC_ARG_POINTER;
   arg.key = GRPC_ARG_SERVICE_CONFIG;
@@ -304,27 +278,27 @@ grpc_arg grpc_method_config_table_create_channel_arg(
 
 // State used by convert_entry() below.
 typedef struct conversion_state {
-  void* (*convert_value)(const grpc_method_config* method_config);
-  const grpc_slice_hash_table_vtable* vtable;
+  void *(*convert_value)(const grpc_method_config *method_config);
+  const grpc_slice_hash_table_vtable *vtable;
   size_t num_entries;
-  grpc_slice_hash_table_entry* entries;
+  grpc_slice_hash_table_entry *entries;
 } conversion_state;
 
 // A function to be passed to grpc_slice_hash_table_iterate() to create
 // a copy of the entries.
-static void convert_entry(const grpc_slice_hash_table_entry* entry,
-                          void* user_data) {
-  conversion_state* state = user_data;
-  state->entries[state->num_entries].key = GRPC_MDSTR_REF(entry->key);
+static void convert_entry(const grpc_slice_hash_table_entry *entry,
+                          void *user_data) {
+  conversion_state *state = user_data;
+  state->entries[state->num_entries].key = grpc_slice_ref_internal(entry->key);
   state->entries[state->num_entries].value = state->convert_value(entry->value);
   state->entries[state->num_entries].vtable = state->vtable;
   ++state->num_entries;
 }
 
-grpc_slice_hash_table* grpc_method_config_table_convert(
-    grpc_exec_ctx* exec_ctx, const grpc_method_config_table* table,
-    void* (*convert_value)(const grpc_method_config* method_config),
-    const grpc_slice_hash_table_vtable* vtable) {
+grpc_slice_hash_table *grpc_method_config_table_convert(
+    grpc_exec_ctx *exec_ctx, const grpc_method_config_table *table,
+    void *(*convert_value)(const grpc_method_config *method_config),
+    const grpc_slice_hash_table_vtable *vtable) {
   // Create an array of the entries in the table with converted values.
   conversion_state state;
   state.convert_value = convert_value;
@@ -334,11 +308,11 @@ grpc_slice_hash_table* grpc_method_config_table_convert(
                              grpc_slice_hash_table_num_entries(table));
   grpc_slice_hash_table_iterate(table, convert_entry, &state);
   // Create a new table based on the array we just constructed.
-  grpc_slice_hash_table* new_table =
+  grpc_slice_hash_table *new_table =
       grpc_slice_hash_table_create(state.num_entries, state.entries);
   // Clean up the array.
   for (size_t i = 0; i < state.num_entries; ++i) {
-    GRPC_MDSTR_UNREF(exec_ctx, state.entries[i].key);
+    grpc_slice_unref_internal(exec_ctx, state.entries[i].key);
     vtable->destroy_value(exec_ctx, state.entries[i].value);
   }
   gpr_free(state.entries);

src/core/lib/transport/transport_op_string.c

@@ -49,12 +49,10 @@
 
 static void put_metadata(gpr_strvec *b, grpc_mdelem *md) {
   gpr_strvec_add(b, gpr_strdup("key="));
-  gpr_strvec_add(
-      b, grpc_dump_slice(md->key->slice, GPR_DUMP_HEX | GPR_DUMP_ASCII));
+  gpr_strvec_add(b, grpc_dump_slice(md->key, GPR_DUMP_HEX | GPR_DUMP_ASCII));
 
   gpr_strvec_add(b, gpr_strdup(" value="));
-  gpr_strvec_add(
-      b, grpc_dump_slice(md->value->slice, GPR_DUMP_HEX | GPR_DUMP_ASCII));
+  gpr_strvec_add(b, grpc_dump_slice(md->value, GPR_DUMP_HEX | GPR_DUMP_ASCII));
 }
 
 static void put_metadata_list(gpr_strvec *b, grpc_metadata_batch md) {

test/core/end2end/cq_verifier.c

@@ -105,6 +105,23 @@ int contains_metadata(grpc_metadata_array *array, const char *key,
   return has_metadata(array->metadata, array->count, key, value);
 }
 
+static int has_metadata_slices(const grpc_metadata *md, size_t count,
+                               grpc_slice key, grpc_slice value) {
+  size_t i;
+  for (i = 0; i < count; i++) {
+    if (0 == grpc_slice_cmp(md[i].key, key) &&
+        0 == grpc_slice_cmp(md[i].value, value)) {
+      return 1;
+    }
+  }
+  return 0;
+}
+
+int contains_metadata_slices(grpc_metadata_array *array, grpc_slice key,
+                             grpc_slice value) {
+  return has_metadata_slices(array->metadata, array->count, key, value);
+}
+
 static grpc_slice merge_slices(grpc_slice *slices, size_t nslices) {
   size_t i;
   size_t len = 0;

test/core/end2end/cq_verifier.h

@@ -71,5 +71,7 @@ int byte_buffer_eq_slice(grpc_byte_buffer *bb, grpc_slice b);
 int byte_buffer_eq_string(grpc_byte_buffer *byte_buffer, const char *string);
 int contains_metadata(grpc_metadata_array *array, const char *key,
                       const char *value);
+int contains_metadata_slices(grpc_metadata_array *array, grpc_slice key,
+                             grpc_slice value);
 
 #endif /* GRPC_TEST_CORE_END2END_CQ_VERIFIER_H */

test/core/end2end/end2end_test_utils.c

@@ -39,13 +39,27 @@
 
 const char *get_host_override_string(const char *str,
                                      grpc_end2end_test_config config) {
-  return (config.feature_mask & FEATURE_MASK_SUPPORTS_AUTHORITY_HEADER ? str
-                                                                       : NULL);
+  if (config.feature_mask & FEATURE_MASK_SUPPORTS_AUTHORITY_HEADER) {
+    return str;
+  } else {
+    return NULL;
+  }
+}
+
+const grpc_slice *get_host_override_slice(const char *str,
+                                          grpc_end2end_test_config config) {
+  const char *r = get_host_override_string(str, config);
+  if (r != NULL) {
+    static grpc_slice ret;
+    ret = grpc_slice_from_static_string(r);
+    return &ret;
+  }
+  return NULL;
 }
 
-void validate_host_override_string(const char *pattern, const char *str,
+void validate_host_override_string(const char *pattern, grpc_slice str,
                                    grpc_end2end_test_config config) {
   if (config.feature_mask & FEATURE_MASK_SUPPORTS_AUTHORITY_HEADER) {
-    GPR_ASSERT(0 == strcmp(str, pattern));
+    GPR_ASSERT(0 == grpc_slice_str_cmp(str, pattern));
   }
 }

test/core/end2end/end2end_tests.h

@@ -72,8 +72,12 @@ void grpc_end2end_tests(int argc, char **argv, grpc_end2end_test_config config);
 
 const char *get_host_override_string(const char *str,
                                      grpc_end2end_test_config config);
+/* Returns a pointer to a statically allocated slice: future invocations
+   overwrite past invocations, not threadsafe, etc... */
+const grpc_slice *get_host_override_slice(const char *str,
+                                          grpc_end2end_test_config config);
 
-void validate_host_override_string(const char *pattern, const char *str,
+void validate_host_override_string(const char *pattern, grpc_slice str,
                                    grpc_end2end_test_config config);
 
 #endif /* GRPC_TEST_CORE_END2END_END2END_TESTS_H */

test/core/end2end/tests/authority_not_supported.c

@@ -103,9 +103,14 @@ static void test_with_authority_header(grpc_end2end_test_config config) {
   grpc_byte_buffer *request_payload =
       grpc_raw_byte_buffer_create(&request_payload_slice, 1);
   gpr_timespec deadline = five_seconds_time();
-  grpc_metadata meta_c[2] = {
-      {"key1", "val1", 4, 0, {{NULL, NULL, NULL, NULL}}},
-      {"key2", "val2", 4, 0, {{NULL, NULL, NULL, NULL}}}};
+  grpc_metadata meta_c[2] = {{grpc_slice_from_static_string("key1"),
+                              grpc_slice_from_static_string("val1"),
+                              0,
+                              {{NULL, NULL, NULL, NULL}}},
+                             {grpc_slice_from_static_string("key2"),
+                              grpc_slice_from_static_string("val2"),
+                              0,
+                              {{NULL, NULL, NULL, NULL}}}};
   grpc_end2end_test_fixture f =
       begin_test(config, "test_with_authority_header", NULL, NULL);
   cq_verifier *cqv = cq_verifier_create(f.cq);
@@ -116,11 +121,12 @@ static void test_with_authority_header(grpc_end2end_test_config config) {
   grpc_byte_buffer *response_payload_recv = NULL;
   grpc_status_code status;
   grpc_call_error error;
-  char *details = NULL;
-  size_t details_capacity = 0;
+  grpc_slice details;
 
+  grpc_slice host = grpc_slice_from_static_string("foo.test.google.fr");
   c = grpc_channel_create_call(f.client, NULL, GRPC_PROPAGATE_DEFAULTS, f.cq,
-                               "/foo", "foo.test.google.fr", deadline, NULL);
+                               grpc_slice_from_static_string("/foo"), &host,
+                               deadline, NULL);
   GPR_ASSERT(c);
 
   grpc_metadata_array_init(&initial_metadata_recv);
@@ -157,7 +163,6 @@ static void test_with_authority_header(grpc_end2end_test_config config) {
   op->data.recv_status_on_client.trailing_metadata = &trailing_metadata_recv;
   op->data.recv_status_on_client.status = &status;
   op->data.recv_status_on_client.status_details = &details;
-  op->data.recv_status_on_client.status_details_capacity = &details_capacity;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -169,7 +174,7 @@ static void test_with_authority_header(grpc_end2end_test_config config) {
 
   GPR_ASSERT(status == GRPC_STATUS_CANCELLED);
 
-  gpr_free(details);
+  grpc_slice_unref(details);
   grpc_metadata_array_destroy(&initial_metadata_recv);
   grpc_metadata_array_destroy(&trailing_metadata_recv);
 

test/core/end2end/tests/bad_hostname.c

@@ -109,11 +109,12 @@ static void simple_request_body(grpc_end2end_test_fixture f) {
   grpc_call_details call_details;
   grpc_status_code status;
   grpc_call_error error;
-  char *details = NULL;
-  size_t details_capacity = 0;
+  grpc_slice details;
 
+  grpc_slice host = grpc_slice_from_static_string("slartibartfast.local");
   c = grpc_channel_create_call(f.client, NULL, GRPC_PROPAGATE_DEFAULTS, f.cq,
-                               "/foo", "slartibartfast.local", deadline, NULL);
+                               grpc_slice_from_static_string("/foo"), &host,
+                               deadline, NULL);
   GPR_ASSERT(c);
 
   grpc_metadata_array_init(&initial_metadata_recv);
@@ -141,7 +142,6 @@ static void simple_request_body(grpc_end2end_test_fixture f) {
   op->data.recv_status_on_client.trailing_metadata = &trailing_metadata_recv;
   op->data.recv_status_on_client.status = &status;
   op->data.recv_status_on_client.status_details = &details;
-  op->data.recv_status_on_client.status_details_capacity = &details_capacity;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -153,7 +153,7 @@ static void simple_request_body(grpc_end2end_test_fixture f) {
 
   GPR_ASSERT(status == GRPC_STATUS_INTERNAL);
 
-  gpr_free(details);
+  grpc_slice_unref(details);
   grpc_metadata_array_destroy(&initial_metadata_recv);
   grpc_metadata_array_destroy(&trailing_metadata_recv);
   grpc_metadata_array_destroy(&request_metadata_recv);

test/core/end2end/tests/binary_metadata.c

@@ -110,25 +110,25 @@ static void test_request_response_with_metadata_and_payload(
       grpc_raw_byte_buffer_create(&response_payload_slice, 1);
   gpr_timespec deadline = five_seconds_time();
   grpc_metadata meta_c[2] = {
-      {"key1-bin",
-       "\xc0\xc1\xc2\xc3\xc4\xc5\xc6\xc7\xc8\xc9\xca\xcb\xcc",
-       13,
+      {grpc_slice_from_static_string("key1-bin"),
+       grpc_slice_from_static_string(
+           "\xc0\xc1\xc2\xc3\xc4\xc5\xc6\xc7\xc8\xc9\xca\xcb\xcc"),
        0,
        {{NULL, NULL, NULL, NULL}}},
-      {"key2-bin",
-       "\x10\x11\x12\x13\x14\x15\x16\x17\x18\x19\x1a\x1b\x1c\x1d",
-       14,
+      {grpc_slice_from_static_string("key2-bin"),
+       grpc_slice_from_static_string(
+           "\x10\x11\x12\x13\x14\x15\x16\x17\x18\x19\x1a\x1b\x1c\x1d"),
        0,
        {{NULL, NULL, NULL, NULL}}}};
   grpc_metadata meta_s[2] = {
-      {"key3-bin",
-       "\xe0\xe1\xe2\xe3\xe4\xe5\xe6\xe7\xe8\xe9\xea\xeb\xec\xed\xee",
-       15,
+      {grpc_slice_from_static_string("key3-bin"),
+       grpc_slice_from_static_string(
+           "\xe0\xe1\xe2\xe3\xe4\xe5\xe6\xe7\xe8\xe9\xea\xeb\xec\xed\xee"),
        0,
        {{NULL, NULL, NULL, NULL}}},
-      {"key4-bin",
-       "\xf0\xf1\xf2\xf3\xf4\xf5\xf6\xf7\xf8\xf9\xfa\xfb\xfc\xfd\xfe\xff",
-       16,
+      {grpc_slice_from_static_string("key4-bin"),
+       grpc_slice_from_static_string(
+           "\xf0\xf1\xf2\xf3\xf4\xf5\xf6\xf7\xf8\xf9\xfa\xfb\xfc\xfd\xfe\xff"),
        0,
        {{NULL, NULL, NULL, NULL}}}};
   grpc_end2end_test_fixture f = begin_test(
@@ -144,13 +144,13 @@ static void test_request_response_with_metadata_and_payload(
   grpc_call_details call_details;
   grpc_status_code status;
   grpc_call_error error;
-  char *details = NULL;
-  size_t details_capacity = 0;
+  grpc_slice details;
   int was_cancelled = 2;
 
   c = grpc_channel_create_call(
-      f.client, NULL, GRPC_PROPAGATE_DEFAULTS, f.cq, "/foo",
-      get_host_override_string("foo.test.google.fr:1234", config), deadline,
+      f.client, NULL, GRPC_PROPAGATE_DEFAULTS, f.cq,
+      grpc_slice_from_static_string("/foo"),
+      get_host_override_slice("foo.test.google.fr:1234", config), deadline,
       NULL);
   GPR_ASSERT(c);
 
@@ -190,7 +190,6 @@ static void test_request_response_with_metadata_and_payload(
   op->data.recv_status_on_client.trailing_metadata = &trailing_metadata_recv;
   op->data.recv_status_on_client.status = &status;
   op->data.recv_status_on_client.status_details = &details;
-  op->data.recv_status_on_client.status_details_capacity = &details_capacity;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -238,7 +237,8 @@ static void test_request_response_with_metadata_and_payload(
   op->op = GRPC_OP_SEND_STATUS_FROM_SERVER;
   op->data.send_status_from_server.trailing_metadata_count = 0;
   op->data.send_status_from_server.status = GRPC_STATUS_OK;
-  op->data.send_status_from_server.status_details = "xyz";
+  grpc_slice status_string = grpc_slice_from_static_string("xyz");
+  op->data.send_status_from_server.status_details = &status_string;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -250,8 +250,8 @@ static void test_request_response_with_metadata_and_payload(
   cq_verify(cqv);
 
   GPR_ASSERT(status == GRPC_STATUS_OK);
-  GPR_ASSERT(0 == strcmp(details, "xyz"));
-  GPR_ASSERT(0 == strcmp(call_details.method, "/foo"));
+  GPR_ASSERT(0 == grpc_slice_str_cmp(details, "xyz"));
+  GPR_ASSERT(0 == grpc_slice_str_cmp(call_details.method, "/foo"));
   validate_host_override_string("foo.test.google.fr:1234", call_details.host,
                                 config);
   GPR_ASSERT(was_cancelled == 0);
@@ -270,7 +270,7 @@ static void test_request_response_with_metadata_and_payload(
       &initial_metadata_recv, "key4-bin",
       "\xf0\xf1\xf2\xf3\xf4\xf5\xf6\xf7\xf8\xf9\xfa\xfb\xfc\xfd\xfe\xff"));
 
-  gpr_free(details);
+  grpc_slice_unref(details);
   grpc_metadata_array_destroy(&initial_metadata_recv);
   grpc_metadata_array_destroy(&trailing_metadata_recv);
   grpc_metadata_array_destroy(&request_metadata_recv);

test/core/end2end/tests/call_creds.c

@@ -156,8 +156,7 @@ static void request_response_with_payload_and_call_creds(
   grpc_call_details call_details;
   grpc_status_code status;
   grpc_call_error error;
-  char *details = NULL;
-  size_t details_capacity = 0;
+  grpc_slice details;
   int was_cancelled = 2;
   grpc_call_credentials *creds = NULL;
   grpc_auth_context *s_auth_context = NULL;
@@ -167,8 +166,9 @@ static void request_response_with_payload_and_call_creds(
   cqv = cq_verifier_create(f.cq);
 
   c = grpc_channel_create_call(
-      f.client, NULL, GRPC_PROPAGATE_DEFAULTS, f.cq, "/foo",
-      get_host_override_string("foo.test.google.fr:1234", config), deadline,
+      f.client, NULL, GRPC_PROPAGATE_DEFAULTS, f.cq,
+      grpc_slice_from_static_string("/foo"),
+      get_host_override_slice("foo.test.google.fr:1234", config), deadline,
       NULL);
   GPR_ASSERT(c);
   creds = grpc_google_iam_credentials_create(iam_token, iam_selector, NULL);
@@ -225,7 +225,6 @@ static void request_response_with_payload_and_call_creds(
   op->data.recv_status_on_client.trailing_metadata = &trailing_metadata_recv;
   op->data.recv_status_on_client.status = &status;
   op->data.recv_status_on_client.status_details = &details;
-  op->data.recv_status_on_client.status_details_capacity = &details_capacity;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -284,7 +283,8 @@ static void request_response_with_payload_and_call_creds(
   op->op = GRPC_OP_SEND_STATUS_FROM_SERVER;
   op->data.send_status_from_server.trailing_metadata_count = 0;
   op->data.send_status_from_server.status = GRPC_STATUS_OK;
-  op->data.send_status_from_server.status_details = "xyz";
+  grpc_slice status_details = grpc_slice_from_static_string("xyz");
+  op->data.send_status_from_server.status_details = &status_details;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -296,8 +296,8 @@ static void request_response_with_payload_and_call_creds(
   cq_verify(cqv);
 
   GPR_ASSERT(status == GRPC_STATUS_OK);
-  GPR_ASSERT(0 == strcmp(details, "xyz"));
-  GPR_ASSERT(0 == strcmp(call_details.method, "/foo"));
+  GPR_ASSERT(0 == grpc_slice_str_cmp(details, "xyz"));
+  GPR_ASSERT(0 == grpc_slice_str_cmp(call_details.method, "/foo"));
   validate_host_override_string("foo.test.google.fr:1234", call_details.host,
                                 config);
   GPR_ASSERT(was_cancelled == 0);
@@ -337,7 +337,7 @@ static void request_response_with_payload_and_call_creds(
       break;
   }
 
-  gpr_free(details);
+  grpc_slice_unref(details);
   grpc_metadata_array_destroy(&initial_metadata_recv);
   grpc_metadata_array_destroy(&trailing_metadata_recv);
   grpc_metadata_array_destroy(&request_metadata_recv);
@@ -391,8 +391,7 @@ static void test_request_with_server_rejecting_client_creds(
   grpc_call_details call_details;
   grpc_status_code status;
   grpc_call_error error;
-  char *details = NULL;
-  size_t details_capacity = 0;
+  grpc_slice details;
   grpc_byte_buffer *response_payload_recv = NULL;
   grpc_slice request_payload_slice =
       grpc_slice_from_copied_string("hello world");
@@ -404,8 +403,9 @@ static void test_request_with_server_rejecting_client_creds(
   cqv = cq_verifier_create(f.cq);
 
   c = grpc_channel_create_call(
-      f.client, NULL, GRPC_PROPAGATE_DEFAULTS, f.cq, "/foo",
-      get_host_override_string("foo.test.google.fr:1234", config), deadline,
+      f.client, NULL, GRPC_PROPAGATE_DEFAULTS, f.cq,
+      grpc_slice_from_static_string("/foo"),
+      get_host_override_slice("foo.test.google.fr:1234", config), deadline,
       NULL);
   GPR_ASSERT(c);
 
@@ -425,7 +425,6 @@ static void test_request_with_server_rejecting_client_creds(
   op->data.recv_status_on_client.trailing_metadata = &trailing_metadata_recv;
   op->data.recv_status_on_client.status = &status;
   op->data.recv_status_on_client.status_details = &details;
-  op->data.recv_status_on_client.status_details_capacity = &details_capacity;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -468,7 +467,7 @@ static void test_request_with_server_rejecting_client_creds(
 
   grpc_byte_buffer_destroy(request_payload);
   grpc_byte_buffer_destroy(response_payload_recv);
-  gpr_free(details);
+  grpc_slice_unref(details);
 
   grpc_call_destroy(c);
 

test/core/end2end/tests/cancel_after_accept.c

@@ -43,6 +43,7 @@
 #include <grpc/support/useful.h>
 
 #include "src/core/lib/channel/channel_args.h"
+#include "src/core/lib/slice/slice_internal.h"
 #include "src/core/lib/transport/metadata.h"
 #include "src/core/lib/transport/method_config.h"
 
@@ -118,8 +119,7 @@ static void test_cancel_after_accept(grpc_end2end_test_config config,
   grpc_call_details call_details;
   grpc_status_code status;
   grpc_call_error error;
-  char *details = NULL;
-  size_t details_capacity = 0;
+  grpc_slice details;
   grpc_byte_buffer *request_payload_recv = NULL;
   grpc_byte_buffer *response_payload_recv = NULL;
   grpc_slice request_payload_slice =
@@ -136,13 +136,13 @@ static void test_cancel_after_accept(grpc_end2end_test_config config,
   if (use_service_config) {
     gpr_timespec timeout = {5, 0, GPR_TIMESPAN};
     grpc_method_config_table_entry entry = {
-        grpc_mdstr_from_string("/service/method"),
+        grpc_slice_from_static_string("/service/method"),
         grpc_method_config_create(NULL, &timeout, NULL, NULL),
     };
     grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
     grpc_method_config_table *method_config_table =
         grpc_method_config_table_create(1, &entry);
-    GRPC_MDSTR_UNREF(&exec_ctx, entry.method_name);
+    grpc_slice_unref_internal(&exec_ctx, entry.method_name);
     grpc_method_config_unref(&exec_ctx, entry.method_config);
     grpc_arg arg =
         grpc_method_config_table_create_channel_arg(method_config_table);
@@ -156,8 +156,9 @@ static void test_cancel_after_accept(grpc_end2end_test_config config,
   cq_verifier *cqv = cq_verifier_create(f.cq);
 
   c = grpc_channel_create_call(
-      f.client, NULL, GRPC_PROPAGATE_DEFAULTS, f.cq, "/service/method",
-      get_host_override_string("foo.test.google.fr:1234", config), deadline,
+      f.client, NULL, GRPC_PROPAGATE_DEFAULTS, f.cq,
+      grpc_slice_from_static_string("/service/method"),
+      get_host_override_slice("foo.test.google.fr:1234", config), deadline,
       NULL);
   GPR_ASSERT(c);
 
@@ -172,7 +173,6 @@ static void test_cancel_after_accept(grpc_end2end_test_config config,
   op->data.recv_status_on_client.trailing_metadata = &trailing_metadata_recv;
   op->data.recv_status_on_client.status = &status;
   op->data.recv_status_on_client.status_details = &details;
-  op->data.recv_status_on_client.status_details_capacity = &details_capacity;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -248,7 +248,7 @@ static void test_cancel_after_accept(grpc_end2end_test_config config,
   grpc_byte_buffer_destroy(response_payload);
   grpc_byte_buffer_destroy(request_payload_recv);
   grpc_byte_buffer_destroy(response_payload_recv);
-  gpr_free(details);
+  grpc_slice_unref(details);
 
   grpc_call_destroy(c);
   grpc_call_destroy(s);

test/core/end2end/tests/cancel_after_client_done.c

@@ -113,8 +113,7 @@ static void test_cancel_after_accept_and_writes_closed(
   grpc_call_details call_details;
   grpc_status_code status;
   grpc_call_error error;
-  char *details = NULL;
-  size_t details_capacity = 0;
+  grpc_slice details;
   grpc_byte_buffer *request_payload_recv = NULL;
   grpc_byte_buffer *response_payload_recv = NULL;
   grpc_slice request_payload_slice =
@@ -128,8 +127,9 @@ static void test_cancel_after_accept_and_writes_closed(
   int was_cancelled = 2;
 
   c = grpc_channel_create_call(
-      f.client, NULL, GRPC_PROPAGATE_DEFAULTS, f.cq, "/foo",
-      get_host_override_string("foo.test.google.fr:1234", config), deadline,
+      f.client, NULL, GRPC_PROPAGATE_DEFAULTS, f.cq,
+      grpc_slice_from_static_string("/foo"),
+      get_host_override_slice("foo.test.google.fr:1234", config), deadline,
       NULL);
   GPR_ASSERT(c);
 
@@ -144,7 +144,6 @@ static void test_cancel_after_accept_and_writes_closed(
   op->data.recv_status_on_client.trailing_metadata = &trailing_metadata_recv;
   op->data.recv_status_on_client.status = &status;
   op->data.recv_status_on_client.status_details = &details;
-  op->data.recv_status_on_client.status_details_capacity = &details_capacity;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -224,7 +223,7 @@ static void test_cancel_after_accept_and_writes_closed(
   grpc_byte_buffer_destroy(response_payload);
   grpc_byte_buffer_destroy(request_payload_recv);
   grpc_byte_buffer_destroy(response_payload_recv);
-  gpr_free(details);
+  grpc_slice_unref(details);
 
   grpc_call_destroy(c);
   grpc_call_destroy(s);

test/core/end2end/tests/cancel_after_invoke.c

@@ -113,8 +113,7 @@ static void test_cancel_after_invoke(grpc_end2end_test_config config,
   grpc_call_details call_details;
   grpc_status_code status;
   grpc_call_error error;
-  char *details = NULL;
-  size_t details_capacity = 0;
+  grpc_slice details;
   grpc_byte_buffer *response_payload_recv = NULL;
   grpc_slice request_payload_slice =
       grpc_slice_from_copied_string("hello world");
@@ -122,8 +121,9 @@ static void test_cancel_after_invoke(grpc_end2end_test_config config,
       grpc_raw_byte_buffer_create(&request_payload_slice, 1);
 
   c = grpc_channel_create_call(
-      f.client, NULL, GRPC_PROPAGATE_DEFAULTS, f.cq, "/foo",
-      get_host_override_string("foo.test.google.fr:1234", config), deadline,
+      f.client, NULL, GRPC_PROPAGATE_DEFAULTS, f.cq,
+      grpc_slice_from_static_string("/foo"),
+      get_host_override_slice("foo.test.google.fr:1234", config), deadline,
       NULL);
   GPR_ASSERT(c);
 
@@ -138,7 +138,6 @@ static void test_cancel_after_invoke(grpc_end2end_test_config config,
   op->data.recv_status_on_client.trailing_metadata = &trailing_metadata_recv;
   op->data.recv_status_on_client.status = &status;
   op->data.recv_status_on_client.status_details = &details;
-  op->data.recv_status_on_client.status_details_capacity = &details_capacity;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -183,7 +182,7 @@ static void test_cancel_after_invoke(grpc_end2end_test_config config,
 
   grpc_byte_buffer_destroy(request_payload);
   grpc_byte_buffer_destroy(response_payload_recv);
-  gpr_free(details);
+  grpc_slice_unref(details);
 
   grpc_call_destroy(c);
 

test/core/end2end/tests/cancel_before_invoke.c

@@ -111,8 +111,7 @@ static void test_cancel_before_invoke(grpc_end2end_test_config config,
   grpc_call_details call_details;
   grpc_status_code status;
   grpc_call_error error;
-  char *details = NULL;
-  size_t details_capacity = 0;
+  grpc_slice details;
   grpc_byte_buffer *response_payload_recv = NULL;
   grpc_slice request_payload_slice =
       grpc_slice_from_copied_string("hello world");
@@ -120,8 +119,9 @@ static void test_cancel_before_invoke(grpc_end2end_test_config config,
       grpc_raw_byte_buffer_create(&request_payload_slice, 1);
 
   c = grpc_channel_create_call(
-      f.client, NULL, GRPC_PROPAGATE_DEFAULTS, f.cq, "/foo",
-      get_host_override_string("foo.test.google.fr:1234", config), deadline,
+      f.client, NULL, GRPC_PROPAGATE_DEFAULTS, f.cq,
+      grpc_slice_from_static_string("/foo"),
+      get_host_override_slice("foo.test.google.fr:1234", config), deadline,
       NULL);
   GPR_ASSERT(c);
 
@@ -138,7 +138,6 @@ static void test_cancel_before_invoke(grpc_end2end_test_config config,
   op->data.recv_status_on_client.trailing_metadata = &trailing_metadata_recv;
   op->data.recv_status_on_client.status = &status;
   op->data.recv_status_on_client.status_details = &details;
-  op->data.recv_status_on_client.status_details_capacity = &details_capacity;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -181,7 +180,7 @@ static void test_cancel_before_invoke(grpc_end2end_test_config config,
 
   grpc_byte_buffer_destroy(request_payload);
   grpc_byte_buffer_destroy(response_payload_recv);
-  gpr_free(details);
+  grpc_slice_unref(details);
 
   grpc_call_destroy(c);
 

test/core/end2end/tests/cancel_in_a_vacuum.c

@@ -106,8 +106,9 @@ static void test_cancel_in_a_vacuum(grpc_end2end_test_config config,
   cq_verifier *v_client = cq_verifier_create(f.cq);
 
   c = grpc_channel_create_call(
-      f.client, NULL, GRPC_PROPAGATE_DEFAULTS, f.cq, "/foo",
-      get_host_override_string("foo.test.google.fr:1234", config), deadline,
+      f.client, NULL, GRPC_PROPAGATE_DEFAULTS, f.cq,
+      grpc_slice_from_static_string("/foo"),
+      get_host_override_slice("foo.test.google.fr:1234", config), deadline,
       NULL);
   GPR_ASSERT(c);
 

test/core/end2end/tests/cancel_with_status.c

@@ -108,14 +108,14 @@ static void simple_request_body(grpc_end2end_test_config config,
   grpc_metadata_array trailing_metadata_recv;
   grpc_status_code status;
   grpc_call_error error;
-  char *details = NULL;
-  size_t details_capacity = 0;
+  grpc_slice details;
 
   gpr_log(GPR_DEBUG, "test with %" PRIuPTR " ops", num_ops);
 
   c = grpc_channel_create_call(
-      f.client, NULL, GRPC_PROPAGATE_DEFAULTS, f.cq, "/foo",
-      get_host_override_string("foo.test.google.fr:1234", config), deadline,
+      f.client, NULL, GRPC_PROPAGATE_DEFAULTS, f.cq,
+      grpc_slice_from_static_string("/foo"),
+      get_host_override_slice("foo.test.google.fr:1234", config), deadline,
       NULL);
   GPR_ASSERT(c);
 
@@ -128,7 +128,6 @@ static void simple_request_body(grpc_end2end_test_config config,
   op->data.recv_status_on_client.trailing_metadata = &trailing_metadata_recv;
   op->data.recv_status_on_client.status = &status;
   op->data.recv_status_on_client.status_details = &details;
-  op->data.recv_status_on_client.status_details_capacity = &details_capacity;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -156,9 +155,9 @@ static void simple_request_body(grpc_end2end_test_config config,
   cq_verify(cqv);
 
   GPR_ASSERT(status == GRPC_STATUS_UNIMPLEMENTED);
-  GPR_ASSERT(0 == strcmp(details, "xyz"));
+  GPR_ASSERT(0 == grpc_slice_str_cmp(details, "xyz"));
 
-  gpr_free(details);
+  grpc_slice_unref(details);
   grpc_metadata_array_destroy(&initial_metadata_recv);
   grpc_metadata_array_destroy(&trailing_metadata_recv);
 

test/core/end2end/tests/compressed_payload.c

@@ -48,6 +48,7 @@
 #include "src/core/lib/channel/channel_args.h"
 #include "src/core/lib/surface/call.h"
 #include "src/core/lib/surface/call_test_only.h"
+#include "src/core/lib/transport/static_metadata.h"
 #include "test/core/end2end/cq_verifier.h"
 
 static void *tag(intptr_t t) { return (void *)t; }
@@ -125,8 +126,7 @@ static void request_for_disabled_algorithm(
   grpc_call_details call_details;
   grpc_status_code status;
   grpc_call_error error;
-  char *details = NULL;
-  size_t details_capacity = 0;
+  grpc_slice details;
   int was_cancelled = 2;
   cq_verifier *cqv;
   char str[1024];
@@ -151,8 +151,9 @@ static void request_for_disabled_algorithm(
   cqv = cq_verifier_create(f.cq);
 
   c = grpc_channel_create_call(
-      f.client, NULL, GRPC_PROPAGATE_DEFAULTS, f.cq, "/foo",
-      get_host_override_string("foo.test.google.fr:1234", config), deadline,
+      f.client, NULL, GRPC_PROPAGATE_DEFAULTS, f.cq,
+      grpc_slice_from_static_string("/foo"),
+      get_host_override_slice("foo.test.google.fr:1234", config), deadline,
       NULL);
   GPR_ASSERT(c);
 
@@ -191,7 +192,6 @@ static void request_for_disabled_algorithm(
   op->data.recv_status_on_client.trailing_metadata = &trailing_metadata_recv;
   op->data.recv_status_on_client.status = &status;
   op->data.recv_status_on_client.status_details = &details;
-  op->data.recv_status_on_client.status_details_capacity = &details_capacity;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -245,13 +245,13 @@ static void request_for_disabled_algorithm(
   gpr_asprintf(&expected_details, "Compression algorithm '%s' is disabled.",
                algo_name);
   /* and we expect a specific reason for it */
-  GPR_ASSERT(0 == strcmp(details, expected_details));
+  GPR_ASSERT(0 == grpc_slice_str_cmp(details, expected_details));
   gpr_free(expected_details);
-  GPR_ASSERT(0 == strcmp(call_details.method, "/foo"));
+  GPR_ASSERT(0 == grpc_slice_str_cmp(call_details.method, "/foo"));
   validate_host_override_string("foo.test.google.fr:1234", call_details.host,
                                 config);
 
-  gpr_free(details);
+  grpc_slice_unref(details);
   grpc_metadata_array_destroy(&initial_metadata_recv);
   grpc_metadata_array_destroy(&trailing_metadata_recv);
   grpc_metadata_array_destroy(&request_metadata_recv);
@@ -305,8 +305,7 @@ static void request_with_payload_template(
   grpc_call_details call_details;
   grpc_status_code status;
   grpc_call_error error;
-  char *details = NULL;
-  size_t details_capacity = 0;
+  grpc_slice details;
   int was_cancelled = 2;
   cq_verifier *cqv;
   char request_str[1024];
@@ -331,8 +330,9 @@ static void request_with_payload_template(
   cqv = cq_verifier_create(f.cq);
 
   c = grpc_channel_create_call(
-      f.client, NULL, GRPC_PROPAGATE_DEFAULTS, f.cq, "/foo",
-      get_host_override_string("foo.test.google.fr:1234", config), deadline,
+      f.client, NULL, GRPC_PROPAGATE_DEFAULTS, f.cq,
+      grpc_slice_from_static_string("/foo"),
+      get_host_override_slice("foo.test.google.fr:1234", config), deadline,
       NULL);
   GPR_ASSERT(c);
 
@@ -362,7 +362,6 @@ static void request_with_payload_template(
   op->data.recv_status_on_client.trailing_metadata = &trailing_metadata_recv;
   op->data.recv_status_on_client.status = &status;
   op->data.recv_status_on_client.status_details = &details;
-  op->data.recv_status_on_client.status_details_capacity = &details_capacity;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -489,7 +488,8 @@ static void request_with_payload_template(
   op->op = GRPC_OP_SEND_STATUS_FROM_SERVER;
   op->data.send_status_from_server.trailing_metadata_count = 0;
   op->data.send_status_from_server.status = GRPC_STATUS_OK;
-  op->data.send_status_from_server.status_details = "xyz";
+  grpc_slice status_details = grpc_slice_from_static_string("xyz");
+  op->data.send_status_from_server.status_details = &status_details;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -503,13 +503,13 @@ static void request_with_payload_template(
   cq_verify(cqv);
 
   GPR_ASSERT(status == GRPC_STATUS_OK);
-  GPR_ASSERT(0 == strcmp(details, "xyz"));
-  GPR_ASSERT(0 == strcmp(call_details.method, "/foo"));
+  GPR_ASSERT(0 == grpc_slice_str_cmp(details, "xyz"));
+  GPR_ASSERT(0 == grpc_slice_str_cmp(call_details.method, "/foo"));
   validate_host_override_string("foo.test.google.fr:1234", call_details.host,
                                 config);
   GPR_ASSERT(was_cancelled == 0);
 
-  gpr_free(details);
+  grpc_slice_unref(details);
   grpc_metadata_array_destroy(&initial_metadata_recv);
   grpc_metadata_array_destroy(&trailing_metadata_recv);
   grpc_metadata_array_destroy(&request_metadata_recv);
@@ -569,17 +569,14 @@ static void test_invoke_request_with_compressed_payload_md_override(
   grpc_metadata gzip_compression_override;
   grpc_metadata identity_compression_override;
 
-  gzip_compression_override.key = GRPC_COMPRESSION_REQUEST_ALGORITHM_MD_KEY;
-  gzip_compression_override.value = "gzip";
-  gzip_compression_override.value_length =
-      strlen(gzip_compression_override.value);
+  gzip_compression_override.key = GRPC_MDSTR_GRPC_INTERNAL_ENCODING_REQUEST;
+  gzip_compression_override.value = grpc_slice_from_static_string("gzip");
   memset(&gzip_compression_override.internal_data, 0,
          sizeof(gzip_compression_override.internal_data));
 
-  identity_compression_override.key = GRPC_COMPRESSION_REQUEST_ALGORITHM_MD_KEY;
-  identity_compression_override.value = "identity";
-  identity_compression_override.value_length =
-      strlen(identity_compression_override.value);
+  identity_compression_override.key = GRPC_MDSTR_GRPC_INTERNAL_ENCODING_REQUEST;
+  identity_compression_override.value =
+      grpc_slice_from_static_string("identity");
   memset(&identity_compression_override.internal_data, 0,
          sizeof(identity_compression_override.internal_data));
 

test/core/end2end/tests/default_host.c

@@ -110,13 +110,13 @@ static void simple_request_body(grpc_end2end_test_fixture f) {
   grpc_call_details call_details;
   grpc_status_code status;
   grpc_call_error error;
-  char *details = NULL;
-  size_t details_capacity = 0;
+  grpc_slice details;
   int was_cancelled = 2;
   char *peer;
 
   c = grpc_channel_create_call(f.client, NULL, GRPC_PROPAGATE_DEFAULTS, f.cq,
-                               "/foo", NULL, deadline, NULL);
+                               grpc_slice_from_static_string("/foo"), NULL,
+                               deadline, NULL);
   GPR_ASSERT(c);
 
   peer = grpc_call_get_peer(c);
@@ -149,7 +149,6 @@ static void simple_request_body(grpc_end2end_test_fixture f) {
   op->data.recv_status_on_client.trailing_metadata = &trailing_metadata_recv;
   op->data.recv_status_on_client.status = &status;
   op->data.recv_status_on_client.status_details = &details;
-  op->data.recv_status_on_client.status_details_capacity = &details_capacity;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -182,7 +181,8 @@ static void simple_request_body(grpc_end2end_test_fixture f) {
   op->op = GRPC_OP_SEND_STATUS_FROM_SERVER;
   op->data.send_status_from_server.trailing_metadata_count = 0;
   op->data.send_status_from_server.status = GRPC_STATUS_UNIMPLEMENTED;
-  op->data.send_status_from_server.status_details = "xyz";
+  grpc_slice status_details = grpc_slice_from_static_string("xyz");
+  op->data.send_status_from_server.status_details = &status_details;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -199,12 +199,12 @@ static void simple_request_body(grpc_end2end_test_fixture f) {
   cq_verify(cqv);
 
   GPR_ASSERT(status == GRPC_STATUS_UNIMPLEMENTED);
-  GPR_ASSERT(0 == strcmp(details, "xyz"));
-  GPR_ASSERT(0 == strcmp(call_details.method, "/foo"));
-  GPR_ASSERT(0 == strncmp(call_details.host, "localhost", 9));
+  GPR_ASSERT(0 == grpc_slice_str_cmp(details, "xyz"));
+  GPR_ASSERT(0 == grpc_slice_str_cmp(call_details.method, "/foo"));
+  GPR_ASSERT(grpc_slice_buf_start_eq(call_details.host, "localhost", 9));
   GPR_ASSERT(was_cancelled == 1);
 
-  gpr_free(details);
+  grpc_slice_unref(details);
   grpc_metadata_array_destroy(&initial_metadata_recv);
   grpc_metadata_array_destroy(&trailing_metadata_recv);
   grpc_metadata_array_destroy(&request_metadata_recv);

test/core/end2end/tests/disappearing_server.c

@@ -93,13 +93,13 @@ static void do_request_and_shutdown_server(grpc_end2end_test_config config,
   grpc_call_details call_details;
   grpc_status_code status;
   grpc_call_error error;
-  char *details = NULL;
-  size_t details_capacity = 0;
+  grpc_slice details;
   int was_cancelled = 2;
 
   c = grpc_channel_create_call(
-      f->client, NULL, GRPC_PROPAGATE_DEFAULTS, f->cq, "/foo",
-      get_host_override_string("foo.test.google.fr:1234", config), deadline,
+      f->client, NULL, GRPC_PROPAGATE_DEFAULTS, f->cq,
+      grpc_slice_from_static_string("/foo"),
+      get_host_override_slice("foo.test.google.fr:1234", config), deadline,
       NULL);
   GPR_ASSERT(c);
 
@@ -128,7 +128,6 @@ static void do_request_and_shutdown_server(grpc_end2end_test_config config,
   op->data.recv_status_on_client.trailing_metadata = &trailing_metadata_recv;
   op->data.recv_status_on_client.status = &status;
   op->data.recv_status_on_client.status_details = &details;
-  op->data.recv_status_on_client.status_details_capacity = &details_capacity;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -156,7 +155,8 @@ static void do_request_and_shutdown_server(grpc_end2end_test_config config,
   op->op = GRPC_OP_SEND_STATUS_FROM_SERVER;
   op->data.send_status_from_server.trailing_metadata_count = 0;
   op->data.send_status_from_server.status = GRPC_STATUS_UNIMPLEMENTED;
-  op->data.send_status_from_server.status_details = "xyz";
+  grpc_slice status_details = grpc_slice_from_static_string("xyz");
+  op->data.send_status_from_server.status_details = &status_details;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -174,13 +174,13 @@ static void do_request_and_shutdown_server(grpc_end2end_test_config config,
   cq_verify(cqv);
 
   GPR_ASSERT(status == GRPC_STATUS_UNIMPLEMENTED);
-  GPR_ASSERT(0 == strcmp(details, "xyz"));
-  GPR_ASSERT(0 == strcmp(call_details.method, "/foo"));
+  GPR_ASSERT(0 == grpc_slice_str_cmp(details, "xyz"));
+  GPR_ASSERT(0 == grpc_slice_str_cmp(call_details.method, "/foo"));
   validate_host_override_string("foo.test.google.fr:1234", call_details.host,
                                 config);
   GPR_ASSERT(was_cancelled == 1);
 
-  gpr_free(details);
+  grpc_slice_unref(details);
   grpc_metadata_array_destroy(&initial_metadata_recv);
   grpc_metadata_array_destroy(&trailing_metadata_recv);
   grpc_metadata_array_destroy(&request_metadata_recv);

test/core/end2end/tests/empty_batch.c

@@ -106,8 +106,9 @@ static void empty_batch_body(grpc_end2end_test_config config,
   grpc_op *op = NULL;
 
   c = grpc_channel_create_call(
-      f.client, NULL, GRPC_PROPAGATE_DEFAULTS, f.cq, "/foo",
-      get_host_override_string("foo.test.google.fr:1234", config), deadline,
+      f.client, NULL, GRPC_PROPAGATE_DEFAULTS, f.cq,
+      grpc_slice_from_static_string("/foo"),
+      get_host_override_slice("foo.test.google.fr:1234", config), deadline,
       NULL);
   GPR_ASSERT(c);
 

test/core/end2end/tests/filter_call_init_fails.c

@@ -125,12 +125,12 @@ static void test_request(grpc_end2end_test_config config) {
   grpc_call_details call_details;
   grpc_status_code status;
   grpc_call_error error;
-  char *details = NULL;
-  size_t details_capacity = 0;
+  grpc_slice details;
 
   c = grpc_channel_create_call(
-      f.client, NULL, GRPC_PROPAGATE_DEFAULTS, f.cq, "/foo",
-      get_host_override_string("foo.test.google.fr:1234", config), deadline,
+      f.client, NULL, GRPC_PROPAGATE_DEFAULTS, f.cq,
+      grpc_slice_from_static_string("/foo"),
+      get_host_override_slice("foo.test.google.fr:1234", config), deadline,
       NULL);
   GPR_ASSERT(c);
 
@@ -165,7 +165,6 @@ static void test_request(grpc_end2end_test_config config) {
   op->data.recv_status_on_client.trailing_metadata = &trailing_metadata_recv;
   op->data.recv_status_on_client.status = &status;
   op->data.recv_status_on_client.status_details = &details;
-  op->data.recv_status_on_client.status_details_capacity = &details_capacity;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -181,9 +180,9 @@ static void test_request(grpc_end2end_test_config config) {
   cq_verify(cqv);
 
   GPR_ASSERT(status == GRPC_STATUS_PERMISSION_DENIED);
-  GPR_ASSERT(0 == strcmp(details, "access denied"));
+  GPR_ASSERT(0 == grpc_slice_str_cmp(details, "access denied"));
 
-  gpr_free(details);
+  grpc_slice_unref(details);
   grpc_metadata_array_destroy(&initial_metadata_recv);
   grpc_metadata_array_destroy(&trailing_metadata_recv);
   grpc_metadata_array_destroy(&request_metadata_recv);

test/core/end2end/tests/filter_causes_close.c

@@ -121,12 +121,12 @@ static void test_request(grpc_end2end_test_config config) {
   grpc_call_details call_details;
   grpc_status_code status;
   grpc_call_error error;
-  char *details = NULL;
-  size_t details_capacity = 0;
+  grpc_slice details;
 
   c = grpc_channel_create_call(
-      f.client, NULL, GRPC_PROPAGATE_DEFAULTS, f.cq, "/foo",
-      get_host_override_string("foo.test.google.fr:1234", config), deadline,
+      f.client, NULL, GRPC_PROPAGATE_DEFAULTS, f.cq,
+      grpc_slice_from_static_string("/foo"),
+      get_host_override_slice("foo.test.google.fr:1234", config), deadline,
       NULL);
   GPR_ASSERT(c);
 
@@ -161,7 +161,6 @@ static void test_request(grpc_end2end_test_config config) {
   op->data.recv_status_on_client.trailing_metadata = &trailing_metadata_recv;
   op->data.recv_status_on_client.status = &status;
   op->data.recv_status_on_client.status_details = &details;
-  op->data.recv_status_on_client.status_details_capacity = &details_capacity;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -177,9 +176,10 @@ static void test_request(grpc_end2end_test_config config) {
   cq_verify(cqv);
 
   GPR_ASSERT(status == GRPC_STATUS_PERMISSION_DENIED);
-  GPR_ASSERT(0 == strcmp(details, "Failure that's not preventable."));
+  GPR_ASSERT(0 ==
+             grpc_slice_str_cmp(details, "Failure that's not preventable."));
 
-  gpr_free(details);
+  grpc_slice_unref(details);
   grpc_metadata_array_destroy(&initial_metadata_recv);
   grpc_metadata_array_destroy(&trailing_metadata_recv);
   grpc_metadata_array_destroy(&request_metadata_recv);

test/core/end2end/tests/graceful_server_shutdown.c

@@ -107,13 +107,13 @@ static void test_early_server_shutdown_finishes_inflight_calls(
   grpc_call_details call_details;
   grpc_status_code status;
   grpc_call_error error;
-  char *details = NULL;
-  size_t details_capacity = 0;
+  grpc_slice details;
   int was_cancelled = 2;
 
   c = grpc_channel_create_call(
-      f.client, NULL, GRPC_PROPAGATE_DEFAULTS, f.cq, "/foo",
-      get_host_override_string("foo.test.google.fr:1234", config), deadline,
+      f.client, NULL, GRPC_PROPAGATE_DEFAULTS, f.cq,
+      grpc_slice_from_static_string("/foo"),
+      get_host_override_slice("foo.test.google.fr:1234", config), deadline,
       NULL);
   GPR_ASSERT(c);
 
@@ -143,7 +143,6 @@ static void test_early_server_shutdown_finishes_inflight_calls(
   op->data.recv_status_on_client.trailing_metadata = &trailing_metadata_recv;
   op->data.recv_status_on_client.status = &status;
   op->data.recv_status_on_client.status_details = &details;
-  op->data.recv_status_on_client.status_details_capacity = &details_capacity;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -171,7 +170,8 @@ static void test_early_server_shutdown_finishes_inflight_calls(
   op->op = GRPC_OP_SEND_STATUS_FROM_SERVER;
   op->data.send_status_from_server.trailing_metadata_count = 0;
   op->data.send_status_from_server.status = GRPC_STATUS_UNIMPLEMENTED;
-  op->data.send_status_from_server.status_details = "xyz";
+  grpc_slice status_details = grpc_slice_from_static_string("xyz");
+  op->data.send_status_from_server.status_details = &status_details;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -191,12 +191,12 @@ static void test_early_server_shutdown_finishes_inflight_calls(
   grpc_call_destroy(s);
 
   GPR_ASSERT(status == GRPC_STATUS_UNIMPLEMENTED);
-  GPR_ASSERT(0 == strcmp(call_details.method, "/foo"));
+  GPR_ASSERT(0 == grpc_slice_str_cmp(call_details.method, "/foo"));
   validate_host_override_string("foo.test.google.fr:1234", call_details.host,
                                 config);
   GPR_ASSERT(was_cancelled == 1);
 
-  gpr_free(details);
+  grpc_slice_unref(details);
   grpc_metadata_array_destroy(&initial_metadata_recv);
   grpc_metadata_array_destroy(&trailing_metadata_recv);
   grpc_metadata_array_destroy(&request_metadata_recv);

test/core/end2end/tests/high_initial_seqno.c

@@ -113,13 +113,13 @@ static void simple_request_body(grpc_end2end_test_config config,
   grpc_call_details call_details;
   grpc_status_code status;
   grpc_call_error error;
-  char *details = NULL;
-  size_t details_capacity = 0;
+  grpc_slice details;
   int was_cancelled = 2;
 
   c = grpc_channel_create_call(
-      f.client, NULL, GRPC_PROPAGATE_DEFAULTS, f.cq, "/foo",
-      get_host_override_string("foo.test.google.fr:1234", config), deadline,
+      f.client, NULL, GRPC_PROPAGATE_DEFAULTS, f.cq,
+      grpc_slice_from_static_string("/foo"),
+      get_host_override_slice("foo.test.google.fr:1234", config), deadline,
       NULL);
   GPR_ASSERT(c);
 
@@ -148,7 +148,6 @@ static void simple_request_body(grpc_end2end_test_config config,
   op->data.recv_status_on_client.trailing_metadata = &trailing_metadata_recv;
   op->data.recv_status_on_client.status = &status;
   op->data.recv_status_on_client.status_details = &details;
-  op->data.recv_status_on_client.status_details_capacity = &details_capacity;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -172,7 +171,8 @@ static void simple_request_body(grpc_end2end_test_config config,
   op->op = GRPC_OP_SEND_STATUS_FROM_SERVER;
   op->data.send_status_from_server.trailing_metadata_count = 0;
   op->data.send_status_from_server.status = GRPC_STATUS_UNIMPLEMENTED;
-  op->data.send_status_from_server.status_details = "xyz";
+  grpc_slice status_details = grpc_slice_from_static_string("xyz");
+  op->data.send_status_from_server.status_details = &status_details;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -189,13 +189,13 @@ static void simple_request_body(grpc_end2end_test_config config,
   cq_verify(cqv);
 
   GPR_ASSERT(status == GRPC_STATUS_UNIMPLEMENTED);
-  GPR_ASSERT(0 == strcmp(details, "xyz"));
-  GPR_ASSERT(0 == strcmp(call_details.method, "/foo"));
+  GPR_ASSERT(0 == grpc_slice_str_cmp(details, "xyz"));
+  GPR_ASSERT(0 == grpc_slice_str_cmp(call_details.method, "/foo"));
   validate_host_override_string("foo.test.google.fr:1234", call_details.host,
                                 config);
   GPR_ASSERT(was_cancelled == 1);
 
-  gpr_free(details);
+  grpc_slice_unref(details);
   grpc_metadata_array_destroy(&initial_metadata_recv);
   grpc_metadata_array_destroy(&trailing_metadata_recv);
   grpc_metadata_array_destroy(&request_metadata_recv);

test/core/end2end/tests/hpack_size.c

@@ -254,24 +254,24 @@ static void simple_request_body(grpc_end2end_test_config config,
   grpc_status_code status;
   grpc_call_error error;
   grpc_metadata extra_metadata[3];
-  char *details = NULL;
-  size_t details_capacity = 0;
+  grpc_slice details;
   int was_cancelled = 2;
 
   memset(extra_metadata, 0, sizeof(extra_metadata));
-  extra_metadata[0].key = "hobbit-first-name";
-  extra_metadata[0].value = hobbits[index % GPR_ARRAY_SIZE(hobbits)][0];
-  extra_metadata[0].value_length = strlen(extra_metadata[0].value);
-  extra_metadata[1].key = "hobbit-second-name";
-  extra_metadata[1].value = hobbits[index % GPR_ARRAY_SIZE(hobbits)][1];
-  extra_metadata[1].value_length = strlen(extra_metadata[1].value);
-  extra_metadata[2].key = "dragon";
-  extra_metadata[2].value = dragons[index % GPR_ARRAY_SIZE(dragons)];
-  extra_metadata[2].value_length = strlen(extra_metadata[2].value);
+  extra_metadata[0].key = grpc_slice_from_static_string("hobbit-first-name");
+  extra_metadata[0].value = grpc_slice_from_static_string(
+      hobbits[index % GPR_ARRAY_SIZE(hobbits)][0]);
+  extra_metadata[1].key = grpc_slice_from_static_string("hobbit-second-name");
+  extra_metadata[1].value = grpc_slice_from_static_string(
+      hobbits[index % GPR_ARRAY_SIZE(hobbits)][1]);
+  extra_metadata[2].key = grpc_slice_from_static_string("dragon");
+  extra_metadata[2].value =
+      grpc_slice_from_static_string(dragons[index % GPR_ARRAY_SIZE(dragons)]);
 
   c = grpc_channel_create_call(
-      f.client, NULL, GRPC_PROPAGATE_DEFAULTS, f.cq, "/foo",
-      get_host_override_string("foo.test.google.fr:1234", config), deadline,
+      f.client, NULL, GRPC_PROPAGATE_DEFAULTS, f.cq,
+      grpc_slice_from_static_string("/foo"),
+      get_host_override_slice("foo.test.google.fr:1234", config), deadline,
       NULL);
   GPR_ASSERT(c);
 
@@ -301,7 +301,6 @@ static void simple_request_body(grpc_end2end_test_config config,
   op->data.recv_status_on_client.trailing_metadata = &trailing_metadata_recv;
   op->data.recv_status_on_client.status = &status;
   op->data.recv_status_on_client.status_details = &details;
-  op->data.recv_status_on_client.status_details_capacity = &details_capacity;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -325,7 +324,8 @@ static void simple_request_body(grpc_end2end_test_config config,
   op->op = GRPC_OP_SEND_STATUS_FROM_SERVER;
   op->data.send_status_from_server.trailing_metadata_count = 0;
   op->data.send_status_from_server.status = GRPC_STATUS_UNIMPLEMENTED;
-  op->data.send_status_from_server.status_details = "xyz";
+  grpc_slice status_details = grpc_slice_from_static_string("xyz");
+  op->data.send_status_from_server.status_details = &status_details;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -342,13 +342,13 @@ static void simple_request_body(grpc_end2end_test_config config,
   cq_verify(cqv);
 
   GPR_ASSERT(status == GRPC_STATUS_UNIMPLEMENTED);
-  GPR_ASSERT(0 == strcmp(details, "xyz"));
-  GPR_ASSERT(0 == strcmp(call_details.method, "/foo"));
+  GPR_ASSERT(0 == grpc_slice_str_cmp(details, "xyz"));
+  GPR_ASSERT(0 == grpc_slice_str_cmp(call_details.method, "/foo"));
   validate_host_override_string("foo.test.google.fr:1234", call_details.host,
                                 config);
   GPR_ASSERT(was_cancelled == 1);
 
-  gpr_free(details);
+  grpc_slice_unref(details);
   grpc_metadata_array_destroy(&initial_metadata_recv);
   grpc_metadata_array_destroy(&trailing_metadata_recv);
   grpc_metadata_array_destroy(&request_metadata_recv);

test/core/end2end/tests/idempotent_request.c

@@ -111,14 +111,14 @@ static void simple_request_body(grpc_end2end_test_config config,
   grpc_call_details call_details;
   grpc_status_code status;
   grpc_call_error error;
-  char *details = NULL;
-  size_t details_capacity = 0;
+  grpc_slice details;
   int was_cancelled = 2;
   char *peer;
 
   c = grpc_channel_create_call(
-      f.client, NULL, GRPC_PROPAGATE_DEFAULTS, f.cq, "/foo",
-      get_host_override_string("foo.test.google.fr:1234", config), deadline,
+      f.client, NULL, GRPC_PROPAGATE_DEFAULTS, f.cq,
+      grpc_slice_from_static_string("/foo"),
+      get_host_override_slice("foo.test.google.fr:1234", config), deadline,
       NULL);
   GPR_ASSERT(c);
 
@@ -152,7 +152,6 @@ static void simple_request_body(grpc_end2end_test_config config,
   op->data.recv_status_on_client.trailing_metadata = &trailing_metadata_recv;
   op->data.recv_status_on_client.status = &status;
   op->data.recv_status_on_client.status_details = &details;
-  op->data.recv_status_on_client.status_details_capacity = &details_capacity;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -185,7 +184,8 @@ static void simple_request_body(grpc_end2end_test_config config,
   op->op = GRPC_OP_SEND_STATUS_FROM_SERVER;
   op->data.send_status_from_server.trailing_metadata_count = 0;
   op->data.send_status_from_server.status = GRPC_STATUS_UNIMPLEMENTED;
-  op->data.send_status_from_server.status_details = "xyz";
+  grpc_slice status_details = grpc_slice_from_static_string("xyz");
+  op->data.send_status_from_server.status_details = &status_details;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -202,14 +202,14 @@ static void simple_request_body(grpc_end2end_test_config config,
   cq_verify(cqv);
 
   GPR_ASSERT(status == GRPC_STATUS_UNIMPLEMENTED);
-  GPR_ASSERT(0 == strcmp(details, "xyz"));
-  GPR_ASSERT(0 == strcmp(call_details.method, "/foo"));
+  GPR_ASSERT(0 == grpc_slice_str_cmp(details, "xyz"));
+  GPR_ASSERT(0 == grpc_slice_str_cmp(call_details.method, "/foo"));
   validate_host_override_string("foo.test.google.fr:1234", call_details.host,
                                 config);
   GPR_ASSERT(GRPC_INITIAL_METADATA_IDEMPOTENT_REQUEST == call_details.flags);
   GPR_ASSERT(was_cancelled == 1);
 
-  gpr_free(details);
+  grpc_slice_unref(details);
   grpc_metadata_array_destroy(&initial_metadata_recv);
   grpc_metadata_array_destroy(&trailing_metadata_recv);
   grpc_metadata_array_destroy(&request_metadata_recv);

test/core/end2end/tests/invoke_large_request.c

@@ -140,13 +140,13 @@ static void test_invoke_large_request(grpc_end2end_test_config config,
   grpc_call_details call_details;
   grpc_status_code status;
   grpc_call_error error;
-  char *details = NULL;
-  size_t details_capacity = 0;
+  grpc_slice details;
   int was_cancelled = 2;
 
   c = grpc_channel_create_call(
-      f.client, NULL, GRPC_PROPAGATE_DEFAULTS, f.cq, "/foo",
-      get_host_override_string("foo.test.google.fr:1234", config), deadline,
+      f.client, NULL, GRPC_PROPAGATE_DEFAULTS, f.cq,
+      grpc_slice_from_static_string("/foo"),
+      get_host_override_slice("foo.test.google.fr:1234", config), deadline,
       NULL);
   GPR_ASSERT(c);
 
@@ -185,7 +185,6 @@ static void test_invoke_large_request(grpc_end2end_test_config config,
   op->data.recv_status_on_client.trailing_metadata = &trailing_metadata_recv;
   op->data.recv_status_on_client.status = &status;
   op->data.recv_status_on_client.status_details = &details;
-  op->data.recv_status_on_client.status_details_capacity = &details_capacity;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -232,7 +231,8 @@ static void test_invoke_large_request(grpc_end2end_test_config config,
   op->op = GRPC_OP_SEND_STATUS_FROM_SERVER;
   op->data.send_status_from_server.trailing_metadata_count = 0;
   op->data.send_status_from_server.status = GRPC_STATUS_UNIMPLEMENTED;
-  op->data.send_status_from_server.status_details = "xyz";
+  grpc_slice status_details = grpc_slice_from_static_string("xyz");
+  op->data.send_status_from_server.status_details = &status_details;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -244,13 +244,13 @@ static void test_invoke_large_request(grpc_end2end_test_config config,
   cq_verify(cqv);
 
   GPR_ASSERT(status == GRPC_STATUS_UNIMPLEMENTED);
-  GPR_ASSERT(0 == strcmp(details, "xyz"));
-  GPR_ASSERT(0 == strcmp(call_details.method, "/foo"));
+  GPR_ASSERT(0 == grpc_slice_str_cmp(details, "xyz"));
+  GPR_ASSERT(0 == grpc_slice_str_cmp(call_details.method, "/foo"));
   validate_host_override_string("foo.test.google.fr:1234", call_details.host,
                                 config);
   GPR_ASSERT(was_cancelled == 1);
 
-  gpr_free(details);
+  grpc_slice_unref(details);
   grpc_metadata_array_destroy(&initial_metadata_recv);
   grpc_metadata_array_destroy(&trailing_metadata_recv);
   grpc_metadata_array_destroy(&request_metadata_recv);

test/core/end2end/tests/large_metadata.c

@@ -122,21 +122,19 @@ static void test_request_with_large_metadata(grpc_end2end_test_config config) {
   grpc_call_details call_details;
   grpc_status_code status;
   grpc_call_error error;
-  char *details = NULL;
-  size_t details_capacity = 0;
+  grpc_slice details;
   int was_cancelled = 2;
 
   c = grpc_channel_create_call(
-      f.client, NULL, GRPC_PROPAGATE_DEFAULTS, f.cq, "/foo",
-      get_host_override_string("foo.test.google.fr:1234", config), deadline,
+      f.client, NULL, GRPC_PROPAGATE_DEFAULTS, f.cq,
+      grpc_slice_from_static_string("/foo"),
+      get_host_override_slice("foo.test.google.fr:1234", config), deadline,
       NULL);
   GPR_ASSERT(c);
 
-  meta.key = "key";
-  meta.value = gpr_malloc(large_size + 1);
-  memset((char *)meta.value, 'a', large_size);
-  ((char *)meta.value)[large_size] = 0;
-  meta.value_length = large_size;
+  meta.key = grpc_slice_from_static_string("key");
+  meta.value = grpc_slice_malloc(large_size);
+  memset(GRPC_SLICE_START_PTR(meta.value), 'a', large_size);
 
   grpc_metadata_array_init(&initial_metadata_recv);
   grpc_metadata_array_init(&trailing_metadata_recv);
@@ -170,7 +168,6 @@ static void test_request_with_large_metadata(grpc_end2end_test_config config) {
   op->data.recv_status_on_client.trailing_metadata = &trailing_metadata_recv;
   op->data.recv_status_on_client.status = &status;
   op->data.recv_status_on_client.status_details = &details;
-  op->data.recv_status_on_client.status_details_capacity = &details_capacity;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -216,7 +213,8 @@ static void test_request_with_large_metadata(grpc_end2end_test_config config) {
   op->op = GRPC_OP_SEND_STATUS_FROM_SERVER;
   op->data.send_status_from_server.trailing_metadata_count = 0;
   op->data.send_status_from_server.status = GRPC_STATUS_OK;
-  op->data.send_status_from_server.status_details = "xyz";
+  grpc_slice status_details = grpc_slice_from_static_string("xyz");
+  op->data.send_status_from_server.status_details = &status_details;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -228,15 +226,17 @@ static void test_request_with_large_metadata(grpc_end2end_test_config config) {
   cq_verify(cqv);
 
   GPR_ASSERT(status == GRPC_STATUS_OK);
-  GPR_ASSERT(0 == strcmp(details, "xyz"));
-  GPR_ASSERT(0 == strcmp(call_details.method, "/foo"));
+  GPR_ASSERT(0 == grpc_slice_str_cmp(details, "xyz"));
+  GPR_ASSERT(0 == grpc_slice_str_cmp(call_details.method, "/foo"));
   validate_host_override_string("foo.test.google.fr:1234", call_details.host,
                                 config);
   GPR_ASSERT(was_cancelled == 0);
   GPR_ASSERT(byte_buffer_eq_string(request_payload_recv, "hello world"));
-  GPR_ASSERT(contains_metadata(&request_metadata_recv, "key", meta.value));
+  GPR_ASSERT(contains_metadata_slices(&request_metadata_recv,
+                                      grpc_slice_from_static_string("key"),
+                                      meta.value));
 
-  gpr_free(details);
+  grpc_slice_unref(details);
   grpc_metadata_array_destroy(&initial_metadata_recv);
   grpc_metadata_array_destroy(&trailing_metadata_recv);
   grpc_metadata_array_destroy(&request_metadata_recv);
@@ -250,7 +250,7 @@ static void test_request_with_large_metadata(grpc_end2end_test_config config) {
   grpc_byte_buffer_destroy(request_payload);
   grpc_byte_buffer_destroy(request_payload_recv);
 
-  gpr_free((char *)meta.value);
+  grpc_slice_unref(meta.value);
 
   end_test(&f);
   config.tear_down_data(&f);

test/core/end2end/tests/load_reporting_hook.c

@@ -146,13 +146,13 @@ static void request_response_with_payload(
   grpc_call_details call_details;
   grpc_status_code status;
   grpc_call_error error;
-  char *details = NULL;
-  size_t details_capacity = 0;
+  grpc_slice details;
   int was_cancelled = 2;
 
   c = grpc_channel_create_call(
-      f.client, NULL, GRPC_PROPAGATE_DEFAULTS, f.cq, method_name,
-      get_host_override_string("foo.test.google.fr:1234", config), deadline,
+      f.client, NULL, GRPC_PROPAGATE_DEFAULTS, f.cq,
+      grpc_slice_from_static_string(method_name),
+      get_host_override_slice("foo.test.google.fr:1234", config), deadline,
       NULL);
   GPR_ASSERT(c);
 
@@ -193,7 +193,6 @@ static void request_response_with_payload(
   op->data.recv_status_on_client.trailing_metadata = &trailing_metadata_recv;
   op->data.recv_status_on_client.status = &status;
   op->data.recv_status_on_client.status_details = &details;
-  op->data.recv_status_on_client.status_details_capacity = &details_capacity;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -242,7 +241,8 @@ static void request_response_with_payload(
   op->data.send_status_from_server.trailing_metadata_count = 1;
   op->data.send_status_from_server.trailing_metadata = trailing_lr_metadata;
   op->data.send_status_from_server.status = GRPC_STATUS_OK;
-  op->data.send_status_from_server.status_details = "xyz";
+  grpc_slice status_details = grpc_slice_from_static_string("xyz");
+  op->data.send_status_from_server.status_details = &status_details;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -255,7 +255,7 @@ static void request_response_with_payload(
 
   GPR_ASSERT(status == GRPC_STATUS_OK);
 
-  gpr_free(details);
+  grpc_slice_unref(details);
   grpc_metadata_array_destroy(&initial_metadata_recv);
   grpc_metadata_array_destroy(&trailing_metadata_recv);
   grpc_metadata_array_destroy(&request_metadata_recv);
@@ -295,15 +295,13 @@ static void test_load_reporting_hook(grpc_end2end_test_config config) {
   grpc_metadata initial_lr_metadata;
   grpc_metadata trailing_lr_metadata;
 
-  initial_lr_metadata.key = GRPC_LB_TOKEN_MD_KEY;
-  initial_lr_metadata.value = "client-token";
-  initial_lr_metadata.value_length = strlen(initial_lr_metadata.value);
+  initial_lr_metadata.key = GRPC_MDSTR_LB_TOKEN;
+  initial_lr_metadata.value = grpc_slice_from_static_string("client-token");
   memset(&initial_lr_metadata.internal_data, 0,
          sizeof(initial_lr_metadata.internal_data));
 
-  trailing_lr_metadata.key = GRPC_LB_COST_MD_KEY;
-  trailing_lr_metadata.value = "server-token";
-  trailing_lr_metadata.value_length = strlen(trailing_lr_metadata.value);
+  trailing_lr_metadata.key = GRPC_MDSTR_LB_COST_BIN;
+  trailing_lr_metadata.value = grpc_slice_from_static_string("server-token");
   memset(&trailing_lr_metadata.internal_data, 0,
          sizeof(trailing_lr_metadata.internal_data));
 

test/core/end2end/tests/max_concurrent_streams.c

@@ -109,13 +109,13 @@ static void simple_request_body(grpc_end2end_test_config config,
   grpc_call_details call_details;
   grpc_status_code status;
   grpc_call_error error;
-  char *details = NULL;
-  size_t details_capacity = 0;
+  grpc_slice details;
   int was_cancelled = 2;
 
   c = grpc_channel_create_call(
-      f.client, NULL, GRPC_PROPAGATE_DEFAULTS, f.cq, "/foo",
-      get_host_override_string("foo.test.google.fr:1234", config), deadline,
+      f.client, NULL, GRPC_PROPAGATE_DEFAULTS, f.cq,
+      grpc_slice_from_static_string("/foo"),
+      get_host_override_slice("foo.test.google.fr:1234", config), deadline,
       NULL);
   GPR_ASSERT(c);
 
@@ -144,7 +144,6 @@ static void simple_request_body(grpc_end2end_test_config config,
   op->data.recv_status_on_client.trailing_metadata = &trailing_metadata_recv;
   op->data.recv_status_on_client.status = &status;
   op->data.recv_status_on_client.status_details = &details;
-  op->data.recv_status_on_client.status_details_capacity = &details_capacity;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -168,7 +167,8 @@ static void simple_request_body(grpc_end2end_test_config config,
   op->op = GRPC_OP_SEND_STATUS_FROM_SERVER;
   op->data.send_status_from_server.trailing_metadata_count = 0;
   op->data.send_status_from_server.status = GRPC_STATUS_UNIMPLEMENTED;
-  op->data.send_status_from_server.status_details = "xyz";
+  grpc_slice status_details = grpc_slice_from_static_string("xyz");
+  op->data.send_status_from_server.status_details = &status_details;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -185,13 +185,13 @@ static void simple_request_body(grpc_end2end_test_config config,
   cq_verify(cqv);
 
   GPR_ASSERT(status == GRPC_STATUS_UNIMPLEMENTED);
-  GPR_ASSERT(0 == strcmp(details, "xyz"));
-  GPR_ASSERT(0 == strcmp(call_details.method, "/foo"));
+  GPR_ASSERT(0 == grpc_slice_str_cmp(details, "xyz"));
+  GPR_ASSERT(0 == grpc_slice_str_cmp(call_details.method, "/foo"));
   validate_host_override_string("foo.test.google.fr:1234", call_details.host,
                                 config);
   GPR_ASSERT(was_cancelled == 1);
 
-  gpr_free(details);
+  grpc_slice_unref(details);
   grpc_metadata_array_destroy(&initial_metadata_recv);
   grpc_metadata_array_destroy(&trailing_metadata_recv);
   grpc_metadata_array_destroy(&request_metadata_recv);
@@ -223,11 +223,9 @@ static void test_max_concurrent_streams(grpc_end2end_test_config config) {
   grpc_metadata_array trailing_metadata_recv2;
   grpc_status_code status1;
   grpc_call_error error;
-  char *details1 = NULL;
-  size_t details_capacity1 = 0;
+  grpc_slice details1;
   grpc_status_code status2;
-  char *details2 = NULL;
-  size_t details_capacity2 = 0;
+  grpc_slice details2;
   grpc_op ops[6];
   grpc_op *op;
   int was_cancelled;
@@ -261,13 +259,15 @@ static void test_max_concurrent_streams(grpc_end2end_test_config config) {
      the first completes */
   deadline = n_seconds_time(1000);
   c1 = grpc_channel_create_call(
-      f.client, NULL, GRPC_PROPAGATE_DEFAULTS, f.cq, "/alpha",
-      get_host_override_string("foo.test.google.fr:1234", config), deadline,
+      f.client, NULL, GRPC_PROPAGATE_DEFAULTS, f.cq,
+      grpc_slice_from_static_string("/alpha"),
+      get_host_override_slice("foo.test.google.fr:1234", config), deadline,
       NULL);
   GPR_ASSERT(c1);
   c2 = grpc_channel_create_call(
-      f.client, NULL, GRPC_PROPAGATE_DEFAULTS, f.cq, "/beta",
-      get_host_override_string("foo.test.google.fr:1234", config), deadline,
+      f.client, NULL, GRPC_PROPAGATE_DEFAULTS, f.cq,
+      grpc_slice_from_static_string("/beta"),
+      get_host_override_slice("foo.test.google.fr:1234", config), deadline,
       NULL);
   GPR_ASSERT(c2);
 
@@ -295,7 +295,6 @@ static void test_max_concurrent_streams(grpc_end2end_test_config config) {
   op->data.recv_status_on_client.trailing_metadata = &trailing_metadata_recv1;
   op->data.recv_status_on_client.status = &status1;
   op->data.recv_status_on_client.status_details = &details1;
-  op->data.recv_status_on_client.status_details_capacity = &details_capacity1;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -327,7 +326,6 @@ static void test_max_concurrent_streams(grpc_end2end_test_config config) {
   op->data.recv_status_on_client.trailing_metadata = &trailing_metadata_recv2;
   op->data.recv_status_on_client.status = &status2;
   op->data.recv_status_on_client.status_details = &details2;
-  op->data.recv_status_on_client.status_details_capacity = &details_capacity2;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -378,7 +376,8 @@ static void test_max_concurrent_streams(grpc_end2end_test_config config) {
   op->op = GRPC_OP_SEND_STATUS_FROM_SERVER;
   op->data.send_status_from_server.trailing_metadata_count = 0;
   op->data.send_status_from_server.status = GRPC_STATUS_UNIMPLEMENTED;
-  op->data.send_status_from_server.status_details = "xyz";
+  grpc_slice status_details = grpc_slice_from_static_string("xyz");
+  op->data.send_status_from_server.status_details = &status_details;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -413,7 +412,7 @@ static void test_max_concurrent_streams(grpc_end2end_test_config config) {
   op->op = GRPC_OP_SEND_STATUS_FROM_SERVER;
   op->data.send_status_from_server.trailing_metadata_count = 0;
   op->data.send_status_from_server.status = GRPC_STATUS_UNIMPLEMENTED;
-  op->data.send_status_from_server.status_details = "xyz";
+  op->data.send_status_from_server.status_details = &status_details;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -431,8 +430,8 @@ static void test_max_concurrent_streams(grpc_end2end_test_config config) {
   grpc_call_destroy(c2);
   grpc_call_destroy(s2);
 
-  gpr_free(details1);
-  gpr_free(details2);
+  grpc_slice_unref(details1);
+  grpc_slice_unref(details2);
   grpc_metadata_array_destroy(&initial_metadata_recv1);
   grpc_metadata_array_destroy(&trailing_metadata_recv1);
   grpc_metadata_array_destroy(&initial_metadata_recv2);

test/core/end2end/tests/max_message_length.c

@@ -43,6 +43,7 @@
 #include <grpc/support/useful.h>
 
 #include "src/core/lib/channel/channel_args.h"
+#include "src/core/lib/slice/slice_internal.h"
 #include "src/core/lib/transport/metadata.h"
 #include "src/core/lib/transport/method_config.h"
 
@@ -129,8 +130,7 @@ static void test_max_message_length_on_request(grpc_end2end_test_config config,
   grpc_call_details call_details;
   grpc_status_code status;
   grpc_call_error error;
-  char *details = NULL;
-  size_t details_capacity = 0;
+  grpc_slice details;
   int was_cancelled = 2;
 
   grpc_channel_args *client_args = NULL;
@@ -141,12 +141,12 @@ static void test_max_message_length_on_request(grpc_end2end_test_config config,
     GPR_ASSERT(send_limit);
     int32_t max_request_message_bytes = 5;
     grpc_method_config_table_entry entry = {
-        grpc_mdstr_from_string("/service/method"),
+        grpc_slice_from_static_string("/service/method"),
         grpc_method_config_create(NULL, NULL, &max_request_message_bytes, NULL),
     };
     grpc_method_config_table *method_config_table =
         grpc_method_config_table_create(1, &entry);
-    GRPC_MDSTR_UNREF(&exec_ctx, entry.method_name);
+    grpc_slice_unref_internal(&exec_ctx, entry.method_name);
     grpc_method_config_unref(&exec_ctx, entry.method_config);
     grpc_arg arg =
         grpc_method_config_table_create_channel_arg(method_config_table);
@@ -180,8 +180,9 @@ static void test_max_message_length_on_request(grpc_end2end_test_config config,
   cqv = cq_verifier_create(f.cq);
 
   c = grpc_channel_create_call(
-      f.client, NULL, GRPC_PROPAGATE_DEFAULTS, f.cq, "/service/method",
-      get_host_override_string("foo.test.google.fr:1234", config),
+      f.client, NULL, GRPC_PROPAGATE_DEFAULTS, f.cq,
+      grpc_slice_from_static_string("/service/method"),
+      get_host_override_slice("foo.test.google.fr:1234", config),
       gpr_inf_future(GPR_CLOCK_REALTIME), NULL);
   GPR_ASSERT(c);
 
@@ -215,7 +216,6 @@ static void test_max_message_length_on_request(grpc_end2end_test_config config,
   op->data.recv_status_on_client.trailing_metadata = &trailing_metadata_recv;
   op->data.recv_status_on_client.status = &status;
   op->data.recv_status_on_client.status_details = &details;
-  op->data.recv_status_on_client.status_details_capacity = &details_capacity;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -254,19 +254,20 @@ static void test_max_message_length_on_request(grpc_end2end_test_config config,
   CQ_EXPECT_COMPLETION(cqv, tag(1), 1);
   cq_verify(cqv);
 
-  GPR_ASSERT(0 == strcmp(call_details.method, "/service/method"));
+  GPR_ASSERT(0 == grpc_slice_str_cmp(call_details.method, "/service/method"));
   validate_host_override_string("foo.test.google.fr:1234", call_details.host,
                                 config);
   GPR_ASSERT(was_cancelled == 1);
 
 done:
   GPR_ASSERT(status == GRPC_STATUS_INVALID_ARGUMENT);
-  GPR_ASSERT(strcmp(details,
-                    send_limit
-                        ? "Sent message larger than max (11 vs. 5)"
-                        : "Received message larger than max (11 vs. 5)") == 0);
+  GPR_ASSERT(
+      grpc_slice_str_cmp(
+          details, send_limit
+                       ? "Sent message larger than max (11 vs. 5)"
+                       : "Received message larger than max (11 vs. 5)") == 0);
 
-  gpr_free(details);
+  grpc_slice_unref(details);
   grpc_metadata_array_destroy(&initial_metadata_recv);
   grpc_metadata_array_destroy(&trailing_metadata_recv);
   grpc_metadata_array_destroy(&request_metadata_recv);
@@ -309,8 +310,7 @@ static void test_max_message_length_on_response(grpc_end2end_test_config config,
   grpc_call_details call_details;
   grpc_status_code status;
   grpc_call_error error;
-  char *details = NULL;
-  size_t details_capacity = 0;
+  grpc_slice details;
   int was_cancelled = 2;
 
   grpc_channel_args *client_args = NULL;
@@ -321,13 +321,13 @@ static void test_max_message_length_on_response(grpc_end2end_test_config config,
     GPR_ASSERT(!send_limit);
     int32_t max_response_message_bytes = 5;
     grpc_method_config_table_entry entry = {
-        grpc_mdstr_from_string("/service/method"),
+        grpc_slice_from_static_string("/service/method"),
         grpc_method_config_create(NULL, NULL, NULL,
                                   &max_response_message_bytes),
     };
     grpc_method_config_table *method_config_table =
         grpc_method_config_table_create(1, &entry);
-    GRPC_MDSTR_UNREF(&exec_ctx, entry.method_name);
+    grpc_slice_unref_internal(&exec_ctx, entry.method_name);
     grpc_method_config_unref(&exec_ctx, entry.method_config);
     grpc_arg arg =
         grpc_method_config_table_create_channel_arg(method_config_table);
@@ -359,9 +359,11 @@ static void test_max_message_length_on_response(grpc_end2end_test_config config,
   }
   cqv = cq_verifier_create(f.cq);
 
-  c = grpc_channel_create_call(f.client, NULL, GRPC_PROPAGATE_DEFAULTS, f.cq,
-                               "/service/method", "foo.test.google.fr:1234",
-                               gpr_inf_future(GPR_CLOCK_REALTIME), NULL);
+  c = grpc_channel_create_call(
+      f.client, NULL, GRPC_PROPAGATE_DEFAULTS, f.cq,
+      grpc_slice_from_static_string("/service/method"),
+      get_host_override_slice("foo.test.google.fr:1234", config),
+      gpr_inf_future(GPR_CLOCK_REALTIME), NULL);
   GPR_ASSERT(c);
 
   grpc_metadata_array_init(&initial_metadata_recv);
@@ -394,7 +396,6 @@ static void test_max_message_length_on_response(grpc_end2end_test_config config,
   op->data.recv_status_on_client.trailing_metadata = &trailing_metadata_recv;
   op->data.recv_status_on_client.status = &status;
   op->data.recv_status_on_client.status_details = &details;
-  op->data.recv_status_on_client.status_details_capacity = &details_capacity;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -428,7 +429,8 @@ static void test_max_message_length_on_response(grpc_end2end_test_config config,
   op->op = GRPC_OP_SEND_STATUS_FROM_SERVER;
   op->data.send_status_from_server.trailing_metadata_count = 0;
   op->data.send_status_from_server.status = GRPC_STATUS_OK;
-  op->data.send_status_from_server.status_details = "xyz";
+  grpc_slice status_details = grpc_slice_from_static_string("xyz");
+  op->data.send_status_from_server.status_details = &status_details;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -439,16 +441,18 @@ static void test_max_message_length_on_response(grpc_end2end_test_config config,
   CQ_EXPECT_COMPLETION(cqv, tag(1), 1);
   cq_verify(cqv);
 
-  GPR_ASSERT(0 == strcmp(call_details.method, "/service/method"));
-  GPR_ASSERT(0 == strcmp(call_details.host, "foo.test.google.fr:1234"));
+  GPR_ASSERT(0 == grpc_slice_str_cmp(call_details.method, "/service/method"));
+  GPR_ASSERT(0 ==
+             grpc_slice_str_cmp(call_details.host, "foo.test.google.fr:1234"));
 
   GPR_ASSERT(status == GRPC_STATUS_INVALID_ARGUMENT);
-  GPR_ASSERT(strcmp(details,
-                    send_limit
-                        ? "Sent message larger than max (11 vs. 5)"
-                        : "Received message larger than max (11 vs. 5)") == 0);
+  GPR_ASSERT(
+      grpc_slice_str_cmp(
+          details, send_limit
+                       ? "Sent message larger than max (11 vs. 5)"
+                       : "Received message larger than max (11 vs. 5)") == 0);
 
-  gpr_free(details);
+  grpc_slice_unref(details);
   grpc_metadata_array_destroy(&initial_metadata_recv);
   grpc_metadata_array_destroy(&trailing_metadata_recv);
   grpc_metadata_array_destroy(&request_metadata_recv);

test/core/end2end/tests/negative_deadline.c

@@ -108,14 +108,14 @@ static void simple_request_body(grpc_end2end_test_config config,
   grpc_metadata_array trailing_metadata_recv;
   grpc_status_code status;
   grpc_call_error error;
-  char *details = NULL;
-  size_t details_capacity = 0;
+  grpc_slice details;
 
   gpr_log(GPR_DEBUG, "test with %" PRIuPTR " ops", num_ops);
 
   c = grpc_channel_create_call(
-      f.client, NULL, GRPC_PROPAGATE_DEFAULTS, f.cq, "/foo",
-      get_host_override_string("foo.test.google.fr:1234", config), deadline,
+      f.client, NULL, GRPC_PROPAGATE_DEFAULTS, f.cq,
+      grpc_slice_from_static_string("/foo"),
+      get_host_override_slice("foo.test.google.fr:1234", config), deadline,
       NULL);
   GPR_ASSERT(c);
 
@@ -128,7 +128,6 @@ static void simple_request_body(grpc_end2end_test_config config,
   op->data.recv_status_on_client.trailing_metadata = &trailing_metadata_recv;
   op->data.recv_status_on_client.status = &status;
   op->data.recv_status_on_client.status_details = &details;
-  op->data.recv_status_on_client.status_details_capacity = &details_capacity;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -155,7 +154,7 @@ static void simple_request_body(grpc_end2end_test_config config,
 
   GPR_ASSERT(status == GRPC_STATUS_DEADLINE_EXCEEDED);
 
-  gpr_free(details);
+  grpc_slice_unref(details);
   grpc_metadata_array_destroy(&initial_metadata_recv);
   grpc_metadata_array_destroy(&trailing_metadata_recv);
 

test/core/end2end/tests/network_status_change.c

@@ -119,13 +119,13 @@ static void test_invoke_network_status_change(grpc_end2end_test_config config) {
   grpc_call_details call_details;
   grpc_status_code status;
   grpc_call_error error;
-  char *details = NULL;
-  size_t details_capacity = 0;
+  grpc_slice details;
   int was_cancelled = 2;
 
   c = grpc_channel_create_call(
-      f.client, NULL, GRPC_PROPAGATE_DEFAULTS, f.cq, "/foo",
-      get_host_override_string("foo.test.google.fr:1234", config), deadline,
+      f.client, NULL, GRPC_PROPAGATE_DEFAULTS, f.cq,
+      grpc_slice_from_static_string("/foo"),
+      get_host_override_slice("foo.test.google.fr:1234", config), deadline,
       NULL);
   GPR_ASSERT(c);
 
@@ -159,7 +159,6 @@ static void test_invoke_network_status_change(grpc_end2end_test_config config) {
   op->data.recv_status_on_client.trailing_metadata = &trailing_metadata_recv;
   op->data.recv_status_on_client.status = &status;
   op->data.recv_status_on_client.status_details = &details;
-  op->data.recv_status_on_client.status_details_capacity = &details_capacity;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -201,7 +200,8 @@ static void test_invoke_network_status_change(grpc_end2end_test_config config) {
   op->op = GRPC_OP_SEND_STATUS_FROM_SERVER;
   op->data.send_status_from_server.trailing_metadata_count = 0;
   op->data.send_status_from_server.status = GRPC_STATUS_OK;
-  op->data.send_status_from_server.status_details = "xyz";
+  grpc_slice status_details = grpc_slice_from_static_string("xyz");
+  op->data.send_status_from_server.status_details = &status_details;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -214,11 +214,11 @@ static void test_invoke_network_status_change(grpc_end2end_test_config config) {
 
   // Expected behavior of a RPC when network is lost.
   GPR_ASSERT(status == GRPC_STATUS_UNAVAILABLE);
-  GPR_ASSERT(0 == strcmp(call_details.method, "/foo"));
+  GPR_ASSERT(0 == grpc_slice_str_cmp(call_details.method, "/foo"));
   validate_host_override_string("foo.test.google.fr:1234", call_details.host,
                                 config);
 
-  gpr_free(details);
+  grpc_slice_unref(details);
   grpc_metadata_array_destroy(&initial_metadata_recv);
   grpc_metadata_array_destroy(&trailing_metadata_recv);
   grpc_metadata_array_destroy(&request_metadata_recv);

test/core/end2end/tests/no_logging.c

@@ -139,14 +139,14 @@ static void simple_request_body(grpc_end2end_test_config config,
   grpc_call_details call_details;
   grpc_status_code status;
   grpc_call_error error;
-  char *details = NULL;
-  size_t details_capacity = 0;
+  grpc_slice details;
   int was_cancelled = 2;
   char *peer;
 
   c = grpc_channel_create_call(
-      f.client, NULL, GRPC_PROPAGATE_DEFAULTS, f.cq, "/foo",
-      get_host_override_string("foo.test.google.fr:1234", config), deadline,
+      f.client, NULL, GRPC_PROPAGATE_DEFAULTS, f.cq,
+      grpc_slice_from_static_string("/foo"),
+      get_host_override_slice("foo.test.google.fr:1234", config), deadline,
       NULL);
   GPR_ASSERT(c);
 
@@ -179,7 +179,6 @@ static void simple_request_body(grpc_end2end_test_config config,
   op->data.recv_status_on_client.trailing_metadata = &trailing_metadata_recv;
   op->data.recv_status_on_client.status = &status;
   op->data.recv_status_on_client.status_details = &details;
-  op->data.recv_status_on_client.status_details_capacity = &details_capacity;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -210,7 +209,8 @@ static void simple_request_body(grpc_end2end_test_config config,
   op->op = GRPC_OP_SEND_STATUS_FROM_SERVER;
   op->data.send_status_from_server.trailing_metadata_count = 0;
   op->data.send_status_from_server.status = GRPC_STATUS_UNIMPLEMENTED;
-  op->data.send_status_from_server.status_details = "xyz";
+  grpc_slice status_details = grpc_slice_from_static_string("xyz");
+  op->data.send_status_from_server.status_details = &status_details;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -227,14 +227,14 @@ static void simple_request_body(grpc_end2end_test_config config,
   cq_verify(cqv);
 
   GPR_ASSERT(status == GRPC_STATUS_UNIMPLEMENTED);
-  GPR_ASSERT(0 == strcmp(details, "xyz"));
-  GPR_ASSERT(0 == strcmp(call_details.method, "/foo"));
+  GPR_ASSERT(0 == grpc_slice_str_cmp(details, "xyz"));
+  GPR_ASSERT(0 == grpc_slice_str_cmp(call_details.method, "/foo"));
   validate_host_override_string("foo.test.google.fr:1234", call_details.host,
                                 config);
   GPR_ASSERT(0 == call_details.flags);
   GPR_ASSERT(was_cancelled == 1);
 
-  gpr_free(details);
+  grpc_slice_unref(details);
   grpc_metadata_array_destroy(&initial_metadata_recv);
   grpc_metadata_array_destroy(&trailing_metadata_recv);
   grpc_metadata_array_destroy(&request_metadata_recv);

test/core/end2end/tests/payload.c

@@ -138,13 +138,13 @@ static void request_response_with_payload(grpc_end2end_test_config config,
   grpc_call_details call_details;
   grpc_status_code status;
   grpc_call_error error;
-  char *details = NULL;
-  size_t details_capacity = 0;
+  grpc_slice details;
   int was_cancelled = 2;
 
   c = grpc_channel_create_call(
-      f.client, NULL, GRPC_PROPAGATE_DEFAULTS, f.cq, "/foo",
-      get_host_override_string("foo.test.google.fr:1234", config), deadline,
+      f.client, NULL, GRPC_PROPAGATE_DEFAULTS, f.cq,
+      grpc_slice_from_static_string("/foo"),
+      get_host_override_slice("foo.test.google.fr:1234", config), deadline,
       NULL);
   GPR_ASSERT(c);
 
@@ -183,7 +183,6 @@ static void request_response_with_payload(grpc_end2end_test_config config,
   op->data.recv_status_on_client.trailing_metadata = &trailing_metadata_recv;
   op->data.recv_status_on_client.status = &status;
   op->data.recv_status_on_client.status_details = &details;
-  op->data.recv_status_on_client.status_details_capacity = &details_capacity;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -230,7 +229,8 @@ static void request_response_with_payload(grpc_end2end_test_config config,
   op->op = GRPC_OP_SEND_STATUS_FROM_SERVER;
   op->data.send_status_from_server.trailing_metadata_count = 0;
   op->data.send_status_from_server.status = GRPC_STATUS_OK;
-  op->data.send_status_from_server.status_details = "xyz";
+  grpc_slice status_details = grpc_slice_from_static_string("xyz");
+  op->data.send_status_from_server.status_details = &status_details;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -242,8 +242,8 @@ static void request_response_with_payload(grpc_end2end_test_config config,
   cq_verify(cqv);
 
   GPR_ASSERT(status == GRPC_STATUS_OK);
-  GPR_ASSERT(0 == strcmp(details, "xyz"));
-  GPR_ASSERT(0 == strcmp(call_details.method, "/foo"));
+  GPR_ASSERT(0 == grpc_slice_str_cmp(details, "xyz"));
+  GPR_ASSERT(0 == grpc_slice_str_cmp(call_details.method, "/foo"));
   validate_host_override_string("foo.test.google.fr:1234", call_details.host,
                                 config);
   GPR_ASSERT(was_cancelled == 0);
@@ -251,7 +251,7 @@ static void request_response_with_payload(grpc_end2end_test_config config,
   GPR_ASSERT(
       byte_buffer_eq_slice(response_payload_recv, response_payload_slice));
 
-  gpr_free(details);
+  grpc_slice_unref(details);
   grpc_metadata_array_destroy(&initial_metadata_recv);
   grpc_metadata_array_destroy(&trailing_metadata_recv);
   grpc_metadata_array_destroy(&request_metadata_recv);

test/core/end2end/tests/ping_pong_streaming.c

@@ -112,8 +112,7 @@ static void test_pingpong_streaming(grpc_end2end_test_config config,
   grpc_call_details call_details;
   grpc_status_code status;
   grpc_call_error error;
-  char *details = NULL;
-  size_t details_capacity = 0;
+  grpc_slice details;
   int was_cancelled = 2;
   grpc_byte_buffer *request_payload;
   grpc_byte_buffer *request_payload_recv;
@@ -126,8 +125,9 @@ static void test_pingpong_streaming(grpc_end2end_test_config config,
       grpc_slice_from_copied_string("hello you");
 
   c = grpc_channel_create_call(
-      f.client, NULL, GRPC_PROPAGATE_DEFAULTS, f.cq, "/foo",
-      get_host_override_string("foo.test.google.fr:1234", config), deadline,
+      f.client, NULL, GRPC_PROPAGATE_DEFAULTS, f.cq,
+      grpc_slice_from_static_string("/foo"),
+      get_host_override_slice("foo.test.google.fr:1234", config), deadline,
       NULL);
   GPR_ASSERT(c);
 
@@ -152,7 +152,6 @@ static void test_pingpong_streaming(grpc_end2end_test_config config,
   op->data.recv_status_on_client.trailing_metadata = &trailing_metadata_recv;
   op->data.recv_status_on_client.status = &status;
   op->data.recv_status_on_client.status_details = &details;
-  op->data.recv_status_on_client.status_details_capacity = &details_capacity;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -248,7 +247,8 @@ static void test_pingpong_streaming(grpc_end2end_test_config config,
   op->op = GRPC_OP_SEND_STATUS_FROM_SERVER;
   op->data.send_status_from_server.trailing_metadata_count = 0;
   op->data.send_status_from_server.status = GRPC_STATUS_UNIMPLEMENTED;
-  op->data.send_status_from_server.status_details = "xyz";
+  grpc_slice status_details = grpc_slice_from_static_string("xyz");
+  op->data.send_status_from_server.status_details = &status_details;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -270,7 +270,7 @@ static void test_pingpong_streaming(grpc_end2end_test_config config,
   grpc_metadata_array_destroy(&trailing_metadata_recv);
   grpc_metadata_array_destroy(&request_metadata_recv);
   grpc_call_details_destroy(&call_details);
-  gpr_free(details);
+  grpc_slice_unref(details);
 
   end_test(&f);
   config.tear_down_data(&f);

test/core/end2end/tests/registered_call.c

@@ -111,8 +111,7 @@ static void simple_request_body(grpc_end2end_test_config config,
   grpc_call_details call_details;
   grpc_status_code status;
   grpc_call_error error;
-  char *details = NULL;
-  size_t details_capacity = 0;
+  grpc_slice details;
   int was_cancelled = 2;
 
   c = grpc_channel_create_registered_call(
@@ -144,7 +143,6 @@ static void simple_request_body(grpc_end2end_test_config config,
   op->data.recv_status_on_client.trailing_metadata = &trailing_metadata_recv;
   op->data.recv_status_on_client.status = &status;
   op->data.recv_status_on_client.status_details = &details;
-  op->data.recv_status_on_client.status_details_capacity = &details_capacity;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -168,7 +166,8 @@ static void simple_request_body(grpc_end2end_test_config config,
   op->op = GRPC_OP_SEND_STATUS_FROM_SERVER;
   op->data.send_status_from_server.trailing_metadata_count = 0;
   op->data.send_status_from_server.status = GRPC_STATUS_UNIMPLEMENTED;
-  op->data.send_status_from_server.status_details = "xyz";
+  grpc_slice status_details = grpc_slice_from_static_string("xyz");
+  op->data.send_status_from_server.status_details = &status_details;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -185,13 +184,13 @@ static void simple_request_body(grpc_end2end_test_config config,
   cq_verify(cqv);
 
   GPR_ASSERT(status == GRPC_STATUS_UNIMPLEMENTED);
-  GPR_ASSERT(0 == strcmp(details, "xyz"));
-  GPR_ASSERT(0 == strcmp(call_details.method, "/foo"));
+  GPR_ASSERT(0 == grpc_slice_str_cmp(details, "xyz"));
+  GPR_ASSERT(0 == grpc_slice_str_cmp(call_details.method, "/foo"));
   validate_host_override_string("foo.test.google.fr:1234", call_details.host,
                                 config);
   GPR_ASSERT(was_cancelled == 1);
 
-  gpr_free(details);
+  grpc_slice_unref(details);
   grpc_metadata_array_destroy(&initial_metadata_recv);
   grpc_metadata_array_destroy(&trailing_metadata_recv);
   grpc_metadata_array_destroy(&request_metadata_recv);

test/core/end2end/tests/request_with_flags.c

@@ -117,13 +117,13 @@ static void test_invoke_request_with_flags(
   grpc_call_details call_details;
   grpc_status_code status;
   grpc_call_error error;
-  char *details = NULL;
-  size_t details_capacity = 0;
+  grpc_slice details;
   grpc_call_error expectation;
 
   c = grpc_channel_create_call(
-      f.client, NULL, GRPC_PROPAGATE_DEFAULTS, f.cq, "/foo",
-      get_host_override_string("foo.test.google.fr:1234", config), deadline,
+      f.client, NULL, GRPC_PROPAGATE_DEFAULTS, f.cq,
+      grpc_slice_from_static_string("/foo"),
+      get_host_override_slice("foo.test.google.fr:1234", config), deadline,
       NULL);
   GPR_ASSERT(c);
 
@@ -157,7 +157,6 @@ static void test_invoke_request_with_flags(
   op->data.recv_status_on_client.trailing_metadata = &trailing_metadata_recv;
   op->data.recv_status_on_client.status = &status;
   op->data.recv_status_on_client.status_details = &details;
-  op->data.recv_status_on_client.status_details_capacity = &details_capacity;
   op->flags = flags_for_op[op->op];
   op->reserved = NULL;
   op++;
@@ -170,7 +169,7 @@ static void test_invoke_request_with_flags(
     cq_verify(cqv);
   }
 
-  gpr_free(details);
+  grpc_slice_unref(details);
   grpc_metadata_array_destroy(&initial_metadata_recv);
   grpc_metadata_array_destroy(&trailing_metadata_recv);
   grpc_metadata_array_destroy(&request_metadata_recv);

test/core/end2end/tests/request_with_payload.c

@@ -116,13 +116,13 @@ static void test_invoke_request_with_payload(grpc_end2end_test_config config) {
   grpc_call_details call_details;
   grpc_status_code status;
   grpc_call_error error;
-  char *details = NULL;
-  size_t details_capacity = 0;
+  grpc_slice details;
   int was_cancelled = 2;
 
   c = grpc_channel_create_call(
-      f.client, NULL, GRPC_PROPAGATE_DEFAULTS, f.cq, "/foo",
-      get_host_override_string("foo.test.google.fr:1234", config), deadline,
+      f.client, NULL, GRPC_PROPAGATE_DEFAULTS, f.cq,
+      grpc_slice_from_static_string("/foo"),
+      get_host_override_slice("foo.test.google.fr:1234", config), deadline,
       NULL);
   GPR_ASSERT(c);
 
@@ -156,7 +156,6 @@ static void test_invoke_request_with_payload(grpc_end2end_test_config config) {
   op->data.recv_status_on_client.trailing_metadata = &trailing_metadata_recv;
   op->data.recv_status_on_client.status = &status;
   op->data.recv_status_on_client.status_details = &details;
-  op->data.recv_status_on_client.status_details_capacity = &details_capacity;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -197,7 +196,8 @@ static void test_invoke_request_with_payload(grpc_end2end_test_config config) {
   op->op = GRPC_OP_SEND_STATUS_FROM_SERVER;
   op->data.send_status_from_server.trailing_metadata_count = 0;
   op->data.send_status_from_server.status = GRPC_STATUS_OK;
-  op->data.send_status_from_server.status_details = "xyz";
+  grpc_slice status_details = grpc_slice_from_static_string("xyz");
+  op->data.send_status_from_server.status_details = &status_details;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -209,14 +209,14 @@ static void test_invoke_request_with_payload(grpc_end2end_test_config config) {
   cq_verify(cqv);
 
   GPR_ASSERT(status == GRPC_STATUS_OK);
-  GPR_ASSERT(0 == strcmp(details, "xyz"));
-  GPR_ASSERT(0 == strcmp(call_details.method, "/foo"));
+  GPR_ASSERT(0 == grpc_slice_str_cmp(details, "xyz"));
+  GPR_ASSERT(0 == grpc_slice_str_cmp(call_details.method, "/foo"));
   validate_host_override_string("foo.test.google.fr:1234", call_details.host,
                                 config);
   GPR_ASSERT(was_cancelled == 0);
   GPR_ASSERT(byte_buffer_eq_string(request_payload_recv, "hello world"));
 
-  gpr_free(details);
+  grpc_slice_unref(details);
   grpc_metadata_array_destroy(&initial_metadata_recv);
   grpc_metadata_array_destroy(&trailing_metadata_recv);
   grpc_metadata_array_destroy(&request_metadata_recv);

test/core/end2end/tests/resource_quota_server.c

@@ -149,8 +149,7 @@ void resource_quota_server(grpc_end2end_test_config config) {
   grpc_call_details *call_details =
       malloc(sizeof(grpc_call_details) * NUM_CALLS);
   grpc_status_code *status = malloc(sizeof(grpc_status_code) * NUM_CALLS);
-  char **details = malloc(sizeof(char *) * NUM_CALLS);
-  size_t *details_capacity = malloc(sizeof(size_t) * NUM_CALLS);
+  grpc_slice *details = malloc(sizeof(char *) * NUM_CALLS);
   grpc_byte_buffer **request_payload_recv =
       malloc(sizeof(grpc_byte_buffer *) * NUM_CALLS);
   int *was_cancelled = malloc(sizeof(int) * NUM_CALLS);
@@ -173,8 +172,6 @@ void resource_quota_server(grpc_end2end_test_config config) {
     grpc_metadata_array_init(&trailing_metadata_recv[i]);
     grpc_metadata_array_init(&request_metadata_recv[i]);
     grpc_call_details_init(&call_details[i]);
-    details[i] = NULL;
-    details_capacity[i] = 0;
     request_payload_recv[i] = NULL;
     was_cancelled[i] = 0;
   }
@@ -190,8 +187,10 @@ void resource_quota_server(grpc_end2end_test_config config) {
 
   for (int i = 0; i < NUM_CALLS; i++) {
     client_calls[i] = grpc_channel_create_call(
-        f.client, NULL, GRPC_PROPAGATE_DEFAULTS, f.cq, "/foo",
-        "foo.test.google.fr", n_seconds_time(60), NULL);
+        f.client, NULL, GRPC_PROPAGATE_DEFAULTS, f.cq,
+        grpc_slice_from_static_string("/foo"),
+        get_host_override_slice("foo.test.google.fr", config),
+        n_seconds_time(60), NULL);
 
     memset(ops, 0, sizeof(ops));
     op = ops;
@@ -219,8 +218,6 @@ void resource_quota_server(grpc_end2end_test_config config) {
         &trailing_metadata_recv[i];
     op->data.recv_status_on_client.status = &status[i];
     op->data.recv_status_on_client.status_details = &details[i];
-    op->data.recv_status_on_client.status_details_capacity =
-        &details_capacity[i];
     op->flags = 0;
     op->reserved = NULL;
     op++;
@@ -260,7 +257,7 @@ void resource_quota_server(grpc_end2end_test_config config) {
       grpc_metadata_array_destroy(&initial_metadata_recv[call_id]);
       grpc_metadata_array_destroy(&trailing_metadata_recv[call_id]);
       grpc_call_destroy(client_calls[call_id]);
-      gpr_free(details[call_id]);
+      grpc_slice_unref(details[call_id]);
 
       pending_client_calls--;
     } else if (ev_tag < SERVER_RECV_BASE_TAG) {
@@ -317,7 +314,8 @@ void resource_quota_server(grpc_end2end_test_config config) {
       op->op = GRPC_OP_SEND_STATUS_FROM_SERVER;
       op->data.send_status_from_server.trailing_metadata_count = 0;
       op->data.send_status_from_server.status = GRPC_STATUS_OK;
-      op->data.send_status_from_server.status_details = "xyz";
+      grpc_slice status_details = grpc_slice_from_static_string("xyz");
+      op->data.send_status_from_server.status_details = &status_details;
       op->flags = 0;
       op->reserved = NULL;
       op++;
@@ -370,7 +368,6 @@ void resource_quota_server(grpc_end2end_test_config config) {
   free(call_details);
   free(status);
   free(details);
-  free(details_capacity);
   free(request_payload_recv);
   free(was_cancelled);
 

test/core/end2end/tests/server_finishes_request.c

@@ -111,13 +111,13 @@ static void simple_request_body(grpc_end2end_test_config config,
   grpc_call_details call_details;
   grpc_status_code status;
   grpc_call_error error;
-  char *details = NULL;
-  size_t details_capacity = 0;
+  grpc_slice details;
   int was_cancelled = 2;
 
   c = grpc_channel_create_call(
-      f.client, NULL, GRPC_PROPAGATE_DEFAULTS, f.cq, "/foo",
-      get_host_override_string("foo.test.google.fr:1234", config), deadline,
+      f.client, NULL, GRPC_PROPAGATE_DEFAULTS, f.cq,
+      grpc_slice_from_static_string("/foo"),
+      get_host_override_slice("foo.test.google.fr:1234", config), deadline,
       NULL);
   GPR_ASSERT(c);
 
@@ -142,7 +142,6 @@ static void simple_request_body(grpc_end2end_test_config config,
   op->data.recv_status_on_client.trailing_metadata = &trailing_metadata_recv;
   op->data.recv_status_on_client.status = &status;
   op->data.recv_status_on_client.status_details = &details;
-  op->data.recv_status_on_client.status_details_capacity = &details_capacity;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -166,7 +165,8 @@ static void simple_request_body(grpc_end2end_test_config config,
   op->op = GRPC_OP_SEND_STATUS_FROM_SERVER;
   op->data.send_status_from_server.trailing_metadata_count = 0;
   op->data.send_status_from_server.status = GRPC_STATUS_UNIMPLEMENTED;
-  op->data.send_status_from_server.status_details = "xyz";
+  grpc_slice status_details = grpc_slice_from_static_string("xyz");
+  op->data.send_status_from_server.status_details = &status_details;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -183,13 +183,13 @@ static void simple_request_body(grpc_end2end_test_config config,
   cq_verify(cqv);
 
   GPR_ASSERT(status == GRPC_STATUS_UNIMPLEMENTED);
-  GPR_ASSERT(0 == strcmp(details, "xyz"));
-  GPR_ASSERT(0 == strcmp(call_details.method, "/foo"));
+  GPR_ASSERT(0 == grpc_slice_str_cmp(details, "xyz"));
+  GPR_ASSERT(0 == grpc_slice_str_cmp(call_details.method, "/foo"));
   validate_host_override_string("foo.test.google.fr:1234", call_details.host,
                                 config);
   GPR_ASSERT(was_cancelled == 1);
 
-  gpr_free(details);
+  grpc_slice_unref(details);
   grpc_metadata_array_destroy(&initial_metadata_recv);
   grpc_metadata_array_destroy(&trailing_metadata_recv);
   grpc_metadata_array_destroy(&request_metadata_recv);

test/core/end2end/tests/shutdown_finishes_calls.c

@@ -100,13 +100,13 @@ static void test_early_server_shutdown_finishes_inflight_calls(
   grpc_call_details call_details;
   grpc_status_code status;
   grpc_call_error error;
-  char *details = NULL;
-  size_t details_capacity = 0;
+  grpc_slice details;
   int was_cancelled = 2;
 
   c = grpc_channel_create_call(
-      f.client, NULL, GRPC_PROPAGATE_DEFAULTS, f.cq, "/foo",
-      get_host_override_string("foo.test.google.fr:1234", config), deadline,
+      f.client, NULL, GRPC_PROPAGATE_DEFAULTS, f.cq,
+      grpc_slice_from_static_string("/foo"),
+      get_host_override_slice("foo.test.google.fr:1234", config), deadline,
       NULL);
   GPR_ASSERT(c);
 
@@ -136,7 +136,6 @@ static void test_early_server_shutdown_finishes_inflight_calls(
   op->data.recv_status_on_client.trailing_metadata = &trailing_metadata_recv;
   op->data.recv_status_on_client.status = &status;
   op->data.recv_status_on_client.status_details = &details;
-  op->data.recv_status_on_client.status_details_capacity = &details_capacity;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -172,12 +171,12 @@ static void test_early_server_shutdown_finishes_inflight_calls(
   grpc_server_destroy(f.server);
 
   GPR_ASSERT(status == GRPC_STATUS_UNAVAILABLE);
-  GPR_ASSERT(0 == strcmp(call_details.method, "/foo"));
+  GPR_ASSERT(0 == grpc_slice_str_cmp(call_details.method, "/foo"));
   validate_host_override_string("foo.test.google.fr:1234", call_details.host,
                                 config);
   GPR_ASSERT(was_cancelled == 1);
 
-  gpr_free(details);
+  grpc_slice_unref(details);
   grpc_metadata_array_destroy(&initial_metadata_recv);
   grpc_metadata_array_destroy(&trailing_metadata_recv);
   grpc_metadata_array_destroy(&request_metadata_recv);

test/core/end2end/tests/simple_cacheable_request.c

@@ -111,12 +111,22 @@ static void test_cacheable_request_response_with_metadata_and_payload(
   grpc_byte_buffer *response_payload =
       grpc_raw_byte_buffer_create(&response_payload_slice, 1);
   gpr_timespec deadline = five_seconds_time();
-  grpc_metadata meta_c[2] = {
-      {"key1", "val1", 4, 0, {{NULL, NULL, NULL, NULL}}},
-      {"key2", "val2", 4, 0, {{NULL, NULL, NULL, NULL}}}};
-  grpc_metadata meta_s[2] = {
-      {"key3", "val3", 4, 0, {{NULL, NULL, NULL, NULL}}},
-      {"key4", "val4", 4, 0, {{NULL, NULL, NULL, NULL}}}};
+  grpc_metadata meta_c[2] = {{grpc_slice_from_static_string("key1"),
+                              grpc_slice_from_static_string("val1"),
+                              0,
+                              {{NULL, NULL, NULL, NULL}}},
+                             {grpc_slice_from_static_string("key2"),
+                              grpc_slice_from_static_string("val2"),
+                              0,
+                              {{NULL, NULL, NULL, NULL}}}};
+  grpc_metadata meta_s[2] = {{grpc_slice_from_static_string("key3"),
+                              grpc_slice_from_static_string("val3"),
+                              0,
+                              {{NULL, NULL, NULL, NULL}}},
+                             {grpc_slice_from_static_string("key4"),
+                              grpc_slice_from_static_string("val4"),
+                              0,
+                              {{NULL, NULL, NULL, NULL}}}};
   grpc_end2end_test_fixture f = begin_test(
       config, "test_cacheable_request_response_with_metadata_and_payload", NULL,
       NULL);
@@ -131,13 +141,13 @@ static void test_cacheable_request_response_with_metadata_and_payload(
   grpc_call_details call_details;
   grpc_status_code status;
   grpc_call_error error;
-  char *details = NULL;
-  size_t details_capacity = 0;
+  grpc_slice details;
   int was_cancelled = 2;
 
   c = grpc_channel_create_call(
-      f.client, NULL, GRPC_PROPAGATE_DEFAULTS, f.cq, "/foo",
-      get_host_override_string("foo.test.google.fr:1234", config), deadline,
+      f.client, NULL, GRPC_PROPAGATE_DEFAULTS, f.cq,
+      grpc_slice_from_static_string("/foo"),
+      get_host_override_slice("foo.test.google.fr:1234", config), deadline,
       NULL);
   GPR_ASSERT(c);
 
@@ -177,7 +187,6 @@ static void test_cacheable_request_response_with_metadata_and_payload(
   op->data.recv_status_on_client.trailing_metadata = &trailing_metadata_recv;
   op->data.recv_status_on_client.status = &status;
   op->data.recv_status_on_client.status_details = &details;
-  op->data.recv_status_on_client.status_details_capacity = &details_capacity;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -225,7 +234,8 @@ static void test_cacheable_request_response_with_metadata_and_payload(
   op->op = GRPC_OP_SEND_STATUS_FROM_SERVER;
   op->data.send_status_from_server.trailing_metadata_count = 0;
   op->data.send_status_from_server.status = GRPC_STATUS_OK;
-  op->data.send_status_from_server.status_details = "xyz";
+  grpc_slice status_details = grpc_slice_from_static_string("xyz");
+  op->data.send_status_from_server.status_details = &status_details;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -237,8 +247,8 @@ static void test_cacheable_request_response_with_metadata_and_payload(
   cq_verify(cqv);
 
   GPR_ASSERT(status == GRPC_STATUS_OK);
-  GPR_ASSERT(0 == strcmp(details, "xyz"));
-  GPR_ASSERT(0 == strcmp(call_details.method, "/foo"));
+  GPR_ASSERT(0 == grpc_slice_str_cmp(details, "xyz"));
+  GPR_ASSERT(0 == grpc_slice_str_cmp(call_details.method, "/foo"));
   validate_host_override_string("foo.test.google.fr:1234", call_details.host,
                                 config);
   if (config.feature_mask & FEATURE_MASK_SUPPORTS_REQUEST_PROXYING) {
@@ -254,7 +264,7 @@ static void test_cacheable_request_response_with_metadata_and_payload(
   GPR_ASSERT(contains_metadata(&initial_metadata_recv, "key3", "val3"));
   GPR_ASSERT(contains_metadata(&initial_metadata_recv, "key4", "val4"));
 
-  gpr_free(details);
+  grpc_slice_unref(details);
   grpc_metadata_array_destroy(&initial_metadata_recv);
   grpc_metadata_array_destroy(&trailing_metadata_recv);
   grpc_metadata_array_destroy(&request_metadata_recv);

test/core/end2end/tests/simple_delayed_request.c

@@ -100,15 +100,15 @@ static void simple_delayed_request_body(grpc_end2end_test_config config,
   grpc_call_details call_details;
   grpc_status_code status;
   grpc_call_error error;
-  char *details = NULL;
-  size_t details_capacity = 0;
+  grpc_slice details;
   int was_cancelled = 2;
 
   config.init_client(f, client_args);
 
   c = grpc_channel_create_call(
-      f->client, NULL, GRPC_PROPAGATE_DEFAULTS, f->cq, "/foo",
-      get_host_override_string("foo.test.google.fr:1234", config), deadline,
+      f->client, NULL, GRPC_PROPAGATE_DEFAULTS, f->cq,
+      grpc_slice_from_static_string("/foo"),
+      get_host_override_slice("foo.test.google.fr:1234", config), deadline,
       NULL);
   GPR_ASSERT(c);
 
@@ -137,7 +137,6 @@ static void simple_delayed_request_body(grpc_end2end_test_config config,
   op->data.recv_status_on_client.trailing_metadata = &trailing_metadata_recv;
   op->data.recv_status_on_client.status = &status;
   op->data.recv_status_on_client.status_details = &details;
-  op->data.recv_status_on_client.status_details_capacity = &details_capacity;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -163,7 +162,8 @@ static void simple_delayed_request_body(grpc_end2end_test_config config,
   op->op = GRPC_OP_SEND_STATUS_FROM_SERVER;
   op->data.send_status_from_server.trailing_metadata_count = 0;
   op->data.send_status_from_server.status = GRPC_STATUS_UNIMPLEMENTED;
-  op->data.send_status_from_server.status_details = "xyz";
+  grpc_slice status_details = grpc_slice_from_static_string("xyz");
+  op->data.send_status_from_server.status_details = &status_details;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -180,13 +180,13 @@ static void simple_delayed_request_body(grpc_end2end_test_config config,
   cq_verify(cqv);
 
   GPR_ASSERT(status == GRPC_STATUS_UNIMPLEMENTED);
-  GPR_ASSERT(0 == strcmp(details, "xyz"));
-  GPR_ASSERT(0 == strcmp(call_details.method, "/foo"));
+  GPR_ASSERT(0 == grpc_slice_str_cmp(details, "xyz"));
+  GPR_ASSERT(0 == grpc_slice_str_cmp(call_details.method, "/foo"));
   validate_host_override_string("foo.test.google.fr:1234", call_details.host,
                                 config);
   GPR_ASSERT(was_cancelled == 1);
 
-  gpr_free(details);
+  grpc_slice_unref(details);
   grpc_metadata_array_destroy(&initial_metadata_recv);
   grpc_metadata_array_destroy(&trailing_metadata_recv);
   grpc_metadata_array_destroy(&request_metadata_recv);

test/core/end2end/tests/simple_metadata.c

@@ -109,12 +109,22 @@ static void test_request_response_with_metadata_and_payload(
   grpc_byte_buffer *response_payload =
       grpc_raw_byte_buffer_create(&response_payload_slice, 1);
   gpr_timespec deadline = five_seconds_time();
-  grpc_metadata meta_c[2] = {
-      {"key1", "val1", 4, 0, {{NULL, NULL, NULL, NULL}}},
-      {"key2", "val2", 4, 0, {{NULL, NULL, NULL, NULL}}}};
-  grpc_metadata meta_s[2] = {
-      {"key3", "val3", 4, 0, {{NULL, NULL, NULL, NULL}}},
-      {"key4", "val4", 4, 0, {{NULL, NULL, NULL, NULL}}}};
+  grpc_metadata meta_c[2] = {{grpc_slice_from_static_string("key1"),
+                              grpc_slice_from_static_string("val1"),
+                              0,
+                              {{NULL, NULL, NULL, NULL}}},
+                             {grpc_slice_from_static_string("key2"),
+                              grpc_slice_from_static_string("val2"),
+                              0,
+                              {{NULL, NULL, NULL, NULL}}}};
+  grpc_metadata meta_s[2] = {{grpc_slice_from_static_string("key3"),
+                              grpc_slice_from_static_string("val3"),
+                              0,
+                              {{NULL, NULL, NULL, NULL}}},
+                             {grpc_slice_from_static_string("key4"),
+                              grpc_slice_from_static_string("val4"),
+                              0,
+                              {{NULL, NULL, NULL, NULL}}}};
   grpc_end2end_test_fixture f = begin_test(
       config, "test_request_response_with_metadata_and_payload", NULL, NULL);
   cq_verifier *cqv = cq_verifier_create(f.cq);
@@ -128,13 +138,13 @@ static void test_request_response_with_metadata_and_payload(
   grpc_call_details call_details;
   grpc_status_code status;
   grpc_call_error error;
-  char *details = NULL;
-  size_t details_capacity = 0;
+  grpc_slice details;
   int was_cancelled = 2;
 
   c = grpc_channel_create_call(
-      f.client, NULL, GRPC_PROPAGATE_DEFAULTS, f.cq, "/foo",
-      get_host_override_string("foo.test.google.fr:1234", config), deadline,
+      f.client, NULL, GRPC_PROPAGATE_DEFAULTS, f.cq,
+      grpc_slice_from_static_string("/foo"),
+      get_host_override_slice("foo.test.google.fr:1234", config), deadline,
       NULL);
   GPR_ASSERT(c);
 
@@ -174,7 +184,6 @@ static void test_request_response_with_metadata_and_payload(
   op->data.recv_status_on_client.trailing_metadata = &trailing_metadata_recv;
   op->data.recv_status_on_client.status = &status;
   op->data.recv_status_on_client.status_details = &details;
-  op->data.recv_status_on_client.status_details_capacity = &details_capacity;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -222,7 +231,8 @@ static void test_request_response_with_metadata_and_payload(
   op->op = GRPC_OP_SEND_STATUS_FROM_SERVER;
   op->data.send_status_from_server.trailing_metadata_count = 0;
   op->data.send_status_from_server.status = GRPC_STATUS_OK;
-  op->data.send_status_from_server.status_details = "xyz";
+  grpc_slice status_details = grpc_slice_from_static_string("xyz");
+  op->data.send_status_from_server.status_details = &status_details;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -234,8 +244,8 @@ static void test_request_response_with_metadata_and_payload(
   cq_verify(cqv);
 
   GPR_ASSERT(status == GRPC_STATUS_OK);
-  GPR_ASSERT(0 == strcmp(details, "xyz"));
-  GPR_ASSERT(0 == strcmp(call_details.method, "/foo"));
+  GPR_ASSERT(0 == grpc_slice_str_cmp(details, "xyz"));
+  GPR_ASSERT(0 == grpc_slice_str_cmp(call_details.method, "/foo"));
   validate_host_override_string("foo.test.google.fr:1234", call_details.host,
                                 config);
   GPR_ASSERT(was_cancelled == 0);
@@ -246,7 +256,7 @@ static void test_request_response_with_metadata_and_payload(
   GPR_ASSERT(contains_metadata(&initial_metadata_recv, "key3", "val3"));
   GPR_ASSERT(contains_metadata(&initial_metadata_recv, "key4", "val4"));
 
-  gpr_free(details);
+  grpc_slice_unref(details);
   grpc_metadata_array_destroy(&initial_metadata_recv);
   grpc_metadata_array_destroy(&trailing_metadata_recv);
   grpc_metadata_array_destroy(&request_metadata_recv);

test/core/end2end/tests/simple_request.c

@@ -111,14 +111,14 @@ static void simple_request_body(grpc_end2end_test_config config,
   grpc_call_details call_details;
   grpc_status_code status;
   grpc_call_error error;
-  char *details = NULL;
-  size_t details_capacity = 0;
+  grpc_slice details;
   int was_cancelled = 2;
   char *peer;
 
   c = grpc_channel_create_call(
-      f.client, NULL, GRPC_PROPAGATE_DEFAULTS, f.cq, "/foo",
-      get_host_override_string("foo.test.google.fr:1234", config), deadline,
+      f.client, NULL, GRPC_PROPAGATE_DEFAULTS, f.cq,
+      grpc_slice_from_static_string("/foo"),
+      get_host_override_slice("foo.test.google.fr:1234", config), deadline,
       NULL);
   GPR_ASSERT(c);
 
@@ -152,7 +152,6 @@ static void simple_request_body(grpc_end2end_test_config config,
   op->data.recv_status_on_client.trailing_metadata = &trailing_metadata_recv;
   op->data.recv_status_on_client.status = &status;
   op->data.recv_status_on_client.status_details = &details;
-  op->data.recv_status_on_client.status_details_capacity = &details_capacity;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -185,7 +184,8 @@ static void simple_request_body(grpc_end2end_test_config config,
   op->op = GRPC_OP_SEND_STATUS_FROM_SERVER;
   op->data.send_status_from_server.trailing_metadata_count = 0;
   op->data.send_status_from_server.status = GRPC_STATUS_UNIMPLEMENTED;
-  op->data.send_status_from_server.status_details = "xyz";
+  grpc_slice status_details = grpc_slice_from_static_string("xyz");
+  op->data.send_status_from_server.status_details = &status_details;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -202,14 +202,14 @@ static void simple_request_body(grpc_end2end_test_config config,
   cq_verify(cqv);
 
   GPR_ASSERT(status == GRPC_STATUS_UNIMPLEMENTED);
-  GPR_ASSERT(0 == strcmp(details, "xyz"));
-  GPR_ASSERT(0 == strcmp(call_details.method, "/foo"));
+  GPR_ASSERT(0 == grpc_slice_str_cmp(details, "xyz"));
+  GPR_ASSERT(0 == grpc_slice_str_cmp(call_details.method, "/foo"));
   validate_host_override_string("foo.test.google.fr:1234", call_details.host,
                                 config);
   GPR_ASSERT(0 == call_details.flags);
   GPR_ASSERT(was_cancelled == 1);
 
-  gpr_free(details);
+  grpc_slice_unref(details);
   grpc_metadata_array_destroy(&initial_metadata_recv);
   grpc_metadata_array_destroy(&trailing_metadata_recv);
   grpc_metadata_array_destroy(&request_metadata_recv);

test/core/end2end/tests/streaming_error_response.c

@@ -121,13 +121,13 @@ static void test(grpc_end2end_test_config config, bool request_status_early) {
   grpc_call_details call_details;
   grpc_status_code status;
   grpc_call_error error;
-  char *details = NULL;
-  size_t details_capacity = 0;
+  grpc_slice details;
   int was_cancelled = 2;
 
   c = grpc_channel_create_call(
-      f.client, NULL, GRPC_PROPAGATE_DEFAULTS, f.cq, "/foo",
-      get_host_override_string("foo.test.google.fr:1234", config), deadline,
+      f.client, NULL, GRPC_PROPAGATE_DEFAULTS, f.cq,
+      grpc_slice_from_static_string("/foo"),
+      get_host_override_slice("foo.test.google.fr:1234", config), deadline,
       NULL);
   GPR_ASSERT(c);
 
@@ -154,7 +154,6 @@ static void test(grpc_end2end_test_config config, bool request_status_early) {
     op->data.recv_status_on_client.trailing_metadata = &trailing_metadata_recv;
     op->data.recv_status_on_client.status = &status;
     op->data.recv_status_on_client.status_details = &details;
-    op->data.recv_status_on_client.status_details_capacity = &details_capacity;
     op++;
   }
   error = grpc_call_start_batch(c, ops, (size_t)(op - ops), tag(1), NULL);
@@ -202,7 +201,8 @@ static void test(grpc_end2end_test_config config, bool request_status_early) {
   op->op = GRPC_OP_SEND_STATUS_FROM_SERVER;
   op->data.send_status_from_server.trailing_metadata_count = 0;
   op->data.send_status_from_server.status = GRPC_STATUS_FAILED_PRECONDITION;
-  op->data.send_status_from_server.status_details = "xyz";
+  grpc_slice status_details = grpc_slice_from_static_string("xyz");
+  op->data.send_status_from_server.status_details = &status_details;
   op++;
   error = grpc_call_start_batch(s, ops, (size_t)(op - ops), tag(104), NULL);
   GPR_ASSERT(GRPC_CALL_OK == error);
@@ -232,7 +232,6 @@ static void test(grpc_end2end_test_config config, bool request_status_early) {
     op->data.recv_status_on_client.trailing_metadata = &trailing_metadata_recv;
     op->data.recv_status_on_client.status = &status;
     op->data.recv_status_on_client.status_details = &details;
-    op->data.recv_status_on_client.status_details_capacity = &details_capacity;
     op++;
     error = grpc_call_start_batch(c, ops, (size_t)(op - ops), tag(3), NULL);
     GPR_ASSERT(GRPC_CALL_OK == error);
@@ -245,13 +244,13 @@ static void test(grpc_end2end_test_config config, bool request_status_early) {
   }
 
   GPR_ASSERT(status == GRPC_STATUS_FAILED_PRECONDITION);
-  GPR_ASSERT(0 == strcmp(details, "xyz"));
-  GPR_ASSERT(0 == strcmp(call_details.method, "/foo"));
+  GPR_ASSERT(0 == grpc_slice_str_cmp(details, "xyz"));
+  GPR_ASSERT(0 == grpc_slice_str_cmp(call_details.method, "/foo"));
   validate_host_override_string("foo.test.google.fr:1234", call_details.host,
                                 config);
   GPR_ASSERT(was_cancelled == 1);
 
-  gpr_free(details);
+  grpc_slice_unref(details);
   grpc_metadata_array_destroy(&initial_metadata_recv);
   grpc_metadata_array_destroy(&trailing_metadata_recv);
   grpc_metadata_array_destroy(&request_metadata_recv);

test/core/end2end/tests/trailing_metadata.c

@@ -109,15 +109,30 @@ static void test_request_response_with_metadata_and_payload(
   grpc_byte_buffer *response_payload =
       grpc_raw_byte_buffer_create(&response_payload_slice, 1);
   gpr_timespec deadline = five_seconds_time();
-  grpc_metadata meta_c[2] = {
-      {"key1", "val1", 4, 0, {{NULL, NULL, NULL, NULL}}},
-      {"key2", "val2", 4, 0, {{NULL, NULL, NULL, NULL}}}};
-  grpc_metadata meta_s[2] = {
-      {"key3", "val3", 4, 0, {{NULL, NULL, NULL, NULL}}},
-      {"key4", "val4", 4, 0, {{NULL, NULL, NULL, NULL}}}};
-  grpc_metadata meta_t[2] = {
-      {"key5", "val5", 4, 0, {{NULL, NULL, NULL, NULL}}},
-      {"key6", "val6", 4, 0, {{NULL, NULL, NULL, NULL}}}};
+  grpc_metadata meta_c[2] = {{grpc_slice_from_static_string("key1"),
+                              grpc_slice_from_static_string("val1"),
+                              0,
+                              {{NULL, NULL, NULL, NULL}}},
+                             {grpc_slice_from_static_string("key2"),
+                              grpc_slice_from_static_string("val2"),
+                              0,
+                              {{NULL, NULL, NULL, NULL}}}};
+  grpc_metadata meta_s[2] = {{grpc_slice_from_static_string("key3"),
+                              grpc_slice_from_static_string("val3"),
+                              0,
+                              {{NULL, NULL, NULL, NULL}}},
+                             {grpc_slice_from_static_string("key4"),
+                              grpc_slice_from_static_string("val4"),
+                              0,
+                              {{NULL, NULL, NULL, NULL}}}};
+  grpc_metadata meta_t[2] = {{grpc_slice_from_static_string("key5"),
+                              grpc_slice_from_static_string("val5"),
+                              0,
+                              {{NULL, NULL, NULL, NULL}}},
+                             {grpc_slice_from_static_string("key6"),
+                              grpc_slice_from_static_string("val6"),
+                              0,
+                              {{NULL, NULL, NULL, NULL}}}};
   grpc_end2end_test_fixture f = begin_test(
       config, "test_request_response_with_metadata_and_payload", NULL, NULL);
   cq_verifier *cqv = cq_verifier_create(f.cq);
@@ -131,13 +146,13 @@ static void test_request_response_with_metadata_and_payload(
   grpc_call_details call_details;
   grpc_status_code status;
   grpc_call_error error;
-  char *details = NULL;
-  size_t details_capacity = 0;
+  grpc_slice details;
   int was_cancelled = 2;
 
   c = grpc_channel_create_call(
-      f.client, NULL, GRPC_PROPAGATE_DEFAULTS, f.cq, "/foo",
-      get_host_override_string("foo.test.google.fr:1234", config), deadline,
+      f.client, NULL, GRPC_PROPAGATE_DEFAULTS, f.cq,
+      grpc_slice_from_static_string("/foo"),
+      get_host_override_slice("foo.test.google.fr:1234", config), deadline,
       NULL);
   GPR_ASSERT(c);
 
@@ -177,7 +192,6 @@ static void test_request_response_with_metadata_and_payload(
   op->data.recv_status_on_client.trailing_metadata = &trailing_metadata_recv;
   op->data.recv_status_on_client.status = &status;
   op->data.recv_status_on_client.status_details = &details;
-  op->data.recv_status_on_client.status_details_capacity = &details_capacity;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -226,7 +240,8 @@ static void test_request_response_with_metadata_and_payload(
   op->data.send_status_from_server.trailing_metadata_count = 2;
   op->data.send_status_from_server.trailing_metadata = meta_t;
   op->data.send_status_from_server.status = GRPC_STATUS_OK;
-  op->data.send_status_from_server.status_details = "xyz";
+  grpc_slice status_details = grpc_slice_from_static_string("xyz");
+  op->data.send_status_from_server.status_details = &status_details;
   op->flags = 0;
   op->reserved = NULL;
   op++;
@@ -238,8 +253,8 @@ static void test_request_response_with_metadata_and_payload(
   cq_verify(cqv);
 
   GPR_ASSERT(status == GRPC_STATUS_OK);
-  GPR_ASSERT(0 == strcmp(details, "xyz"));
-  GPR_ASSERT(0 == strcmp(call_details.method, "/foo"));
+  GPR_ASSERT(0 == grpc_slice_str_cmp(details, "xyz"));
+  GPR_ASSERT(0 == grpc_slice_str_cmp(call_details.method, "/foo"));
   validate_host_override_string("foo.test.google.fr:1234", call_details.host,
                                 config);
   GPR_ASSERT(byte_buffer_eq_string(request_payload_recv, "hello world"));
@@ -251,7 +266,7 @@ static void test_request_response_with_metadata_and_payload(
   GPR_ASSERT(contains_metadata(&trailing_metadata_recv, "key5", "val5"));
   GPR_ASSERT(contains_metadata(&trailing_metadata_recv, "key6", "val6"));
 
-  gpr_free(details);
+  grpc_slice_unref(details);
   grpc_metadata_array_destroy(&initial_metadata_recv);
   grpc_metadata_array_destroy(&trailing_metadata_recv);
   grpc_metadata_array_destroy(&request_metadata_recv);