Merge branch 'slice_with_exec_ctx' into eliminate_mdstr

3 files changed, 329 insertions, 2 deletions

diff --git a/src/core/lib/transport/service_config.c b/src/core/lib/transport/service_config.c
new file mode 100644
index 0000000000..8073a46105
--- /dev/null
+++ b/src/core/lib/transport/service_config.c
@@ -0,0 +1,254 @@
+//
+// Copyright 2015, Google Inc.
+// All rights reserved.
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+//
+
+#include "src/core/lib/transport/service_config.h"
+
+#include <string.h>
+
+#include <grpc/impl/codegen/grpc_types.h>
+#include <grpc/support/alloc.h>
+#include <grpc/support/log.h>
+#include <grpc/support/string_util.h>
+
+#include "src/core/lib/json/json.h"
+#include "src/core/lib/slice/slice_hash_table.h"
+#include "src/core/lib/slice/slice_internal.h"
+#include "src/core/lib/slice/slice_string_helpers.h"
+#include "src/core/lib/support/string.h"
+
+// The main purpose of the code here is to parse the service config in
+// JSON form, which will look like this:
+//
+// {
+//   "loadBalancingPolicy": "string",  // optional
+//   "methodConfig": [  // array of one or more method_config objects
+//     {
+//       "name": [  // array of one or more name objects
+//         {
+//           "service": "string",  // required
+//           "method": "string",  // optional
+//         }
+//       ],
+//       // remaining fields are optional.
+//       // see https://developers.google.com/protocol-buffers/docs/proto3#json
+//       // for format details.
+//       "waitForReady": bool,
+//       "timeout": "duration_string",
+//       "maxRequestMessageBytes": "int64_string",
+//       "maxResponseMessageBytes": "int64_string",
+//     }
+//   ]
+// }
+
+struct grpc_service_config {
+  char* json_string;  // Underlying storage for json_tree.
+  grpc_json* json_tree;
+};
+
+grpc_service_config* grpc_service_config_create(const char* json_string) {
+  grpc_service_config* service_config = gpr_malloc(sizeof(*service_config));
+  service_config->json_string = gpr_strdup(json_string);
+  service_config->json_tree =
+      grpc_json_parse_string(service_config->json_string);
+  if (service_config->json_tree == NULL) {
+    gpr_log(GPR_INFO, "failed to parse JSON for service config");
+    gpr_free(service_config->json_string);
+    gpr_free(service_config);
+    return NULL;
+  }
+  return service_config;
+}
+
+void grpc_service_config_destroy(grpc_service_config* service_config) {
+  grpc_json_destroy(service_config->json_tree);
+  gpr_free(service_config->json_string);
+  gpr_free(service_config);
+}
+
+const char* grpc_service_config_get_lb_policy_name(
+    const grpc_service_config* service_config) {
+  const grpc_json* json = service_config->json_tree;
+  if (json->type != GRPC_JSON_OBJECT || json->key != NULL) return NULL;
+  const char* lb_policy_name = NULL;
+  for (grpc_json* field = json->child; field != NULL; field = field->next) {
+    if (field->key == NULL) return NULL;
+    if (strcmp(field->key, "loadBalancingPolicy") == 0) {
+      if (lb_policy_name != NULL) return NULL;  // Duplicate.
+      if (field->type != GRPC_JSON_STRING) return NULL;
+      lb_policy_name = field->value;
+    }
+  }
+  return lb_policy_name;
+}
+
+// Returns the number of names specified in the method config \a json.
+static size_t count_names_in_method_config_json(grpc_json* json) {
+  size_t num_names = 0;
+  for (grpc_json* field = json->child; field != NULL; field = field->next) {
+    if (field->key != NULL && strcmp(field->key, "name") == 0) ++num_names;
+  }
+  return num_names;
+}
+
+// Returns a path string for the JSON name object specified by \a json.
+// Returns NULL on error.  Caller takes ownership of result.
+static char* parse_json_method_name(grpc_json* json) {
+  if (json->type != GRPC_JSON_OBJECT) return NULL;
+  const char* service_name = NULL;
+  const char* method_name = NULL;
+  for (grpc_json* child = json->child; child != NULL; child = child->next) {
+    if (child->key == NULL) return NULL;
+    if (child->type != GRPC_JSON_STRING) return NULL;
+    if (strcmp(child->key, "service") == 0) {
+      if (service_name != NULL) return NULL;  // Duplicate.
+      if (child->value == NULL) return NULL;
+      service_name = child->value;
+    } else if (strcmp(child->key, "method") == 0) {
+      if (method_name != NULL) return NULL;  // Duplicate.
+      if (child->value == NULL) return NULL;
+      method_name = child->value;
+    }
+  }
+  if (service_name == NULL) return NULL;  // Required field.
+  char* path;
+  gpr_asprintf(&path, "/%s/%s", service_name,
+               method_name == NULL ? "*" : method_name);
+  return path;
+}
+
+// Parses the method config from \a json.  Adds an entry to \a entries for
+// each name found, incrementing \a idx for each entry added.
+// Returns false on error.
+static bool parse_json_method_config(
+    grpc_exec_ctx* exec_ctx, grpc_json* json,
+    void* (*create_value)(const grpc_json* method_config_json),
+    const grpc_slice_hash_table_vtable* vtable,
+    grpc_slice_hash_table_entry* entries, size_t* idx) {
+  // Construct value.
+  void* method_config = create_value(json);
+  if (method_config == NULL) return false;
+  // Construct list of paths.
+  bool success = false;
+  gpr_strvec paths;
+  gpr_strvec_init(&paths);
+  for (grpc_json* child = json->child; child != NULL; child = child->next) {
+    if (child->key == NULL) continue;
+    if (strcmp(child->key, "name") == 0) {
+      if (child->type != GRPC_JSON_ARRAY) goto done;
+      for (grpc_json* name = child->child; name != NULL; name = name->next) {
+        char* path = parse_json_method_name(name);
+        gpr_strvec_add(&paths, path);
+      }
+    }
+  }
+  if (paths.count == 0) goto done;  // No names specified.
+  // Add entry for each path.
+  for (size_t i = 0; i < paths.count; ++i) {
+    entries[*idx].key = grpc_slice_from_copied_string(paths.strs[i]);
+    entries[*idx].value = vtable->copy_value(method_config);
+    entries[*idx].vtable = vtable;
+    ++*idx;
+  }
+  success = true;
+done:
+  vtable->destroy_value(exec_ctx, method_config);
+  gpr_strvec_destroy(&paths);
+  return success;
+}
+
+grpc_slice_hash_table* grpc_service_config_create_method_config_table(
+    grpc_exec_ctx* exec_ctx, const grpc_service_config* service_config,
+    void* (*create_value)(const grpc_json* method_config_json),
+    const grpc_slice_hash_table_vtable* vtable) {
+  const grpc_json* json = service_config->json_tree;
+  // Traverse parsed JSON tree.
+  if (json->type != GRPC_JSON_OBJECT || json->key != NULL) return NULL;
+  size_t num_entries = 0;
+  grpc_slice_hash_table_entry* entries = NULL;
+  for (grpc_json* field = json->child; field != NULL; field = field->next) {
+    if (field->key == NULL) return NULL;
+    if (strcmp(field->key, "methodConfig") == 0) {
+      if (entries != NULL) return NULL;  // Duplicate.
+      if (field->type != GRPC_JSON_ARRAY) return NULL;
+      // Find number of entries.
+      for (grpc_json* method = field->child; method != NULL;
+           method = method->next) {
+        num_entries += count_names_in_method_config_json(method);
+      }
+      // Populate method config table entries.
+      entries = gpr_malloc(num_entries * sizeof(grpc_slice_hash_table_entry));
+      size_t idx = 0;
+      for (grpc_json* method = field->child; method != NULL;
+           method = method->next) {
+        if (!parse_json_method_config(exec_ctx, method, create_value, vtable,
+                                      entries, &idx)) {
+          return NULL;
+        }
+      }
+      GPR_ASSERT(idx == num_entries);
+    }
+  }
+  // Instantiate method config table.
+  grpc_slice_hash_table* method_config_table = NULL;
+  if (entries != NULL) {
+    method_config_table = grpc_slice_hash_table_create(num_entries, entries);
+    // Clean up.
+    for (size_t i = 0; i < num_entries; ++i) {
+      grpc_slice_unref_internal(exec_ctx, entries[i].key);
+      vtable->destroy_value(exec_ctx, entries[i].value);
+    }
+    gpr_free(entries);
+  }
+  return method_config_table;
+}
+
+void* grpc_method_config_table_get(grpc_exec_ctx* exec_ctx,
+                                   const grpc_slice_hash_table* table,
+                                   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) {
+    char* path_str = grpc_dump_slice(path, GPR_DUMP_ASCII);
+    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_slice_from_copied_string(buf);
+    gpr_free(buf);
+    value = grpc_slice_hash_table_get(table, wildcard_path);
+    grpc_slice_unref_internal(exec_ctx, wildcard_path);
+    gpr_free(path_str);
+  }
+  return value;
+}
diff --git a/src/core/lib/transport/service_config.h b/src/core/lib/transport/service_config.h
new file mode 100644
index 0000000000..ab964b3bae
--- /dev/null
+++ b/src/core/lib/transport/service_config.h
@@ -0,0 +1,71 @@
+//
+// Copyright 2016, Google Inc.
+// All rights reserved.
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+//
+
+#ifndef GRPC_CORE_LIB_TRANSPORT_SERVICE_CONFIG_H
+#define GRPC_CORE_LIB_TRANSPORT_SERVICE_CONFIG_H
+
+#include <grpc/impl/codegen/grpc_types.h>
+
+#include "src/core/lib/json/json.h"
+#include "src/core/lib/slice/slice_hash_table.h"
+
+typedef struct grpc_service_config grpc_service_config;
+
+grpc_service_config* grpc_service_config_create(const char* json_string);
+void grpc_service_config_destroy(grpc_service_config* service_config);
+
+/// Gets the LB policy name from \a service_config.
+/// Returns NULL if no LB policy name was specified.
+/// Caller does NOT take ownership.
+const char* grpc_service_config_get_lb_policy_name(
+    const grpc_service_config* service_config);
+
+/// Creates a method config table based on the data in \a json.
+/// The table's keys are request paths.  The table's value type is
+/// returned by \a create_value(), based on data parsed from the JSON tree.
+/// \a vtable provides methods used to manage the values.
+/// Returns NULL on error.
+grpc_slice_hash_table* grpc_service_config_create_method_config_table(
+    grpc_exec_ctx* exec_ctx, const grpc_service_config* service_config,
+    void* (*create_value)(const grpc_json* method_config_json),
+    const grpc_slice_hash_table_vtable* vtable);
+
+/// A helper function for looking up values in the table returned by
+/// \a grpc_service_config_create_method_config_table().
+/// Gets the method config for the specified \a path, which should be of
+/// the form "/service/method".
+/// Returns NULL if the method has no config.
+/// Caller does NOT own a reference to the result.
+void* grpc_method_config_table_get(grpc_exec_ctx* exec_ctx,
+                                   const grpc_slice_hash_table* table,
+                                   const grpc_slice path);
+
+#endif /* GRPC_CORE_LIB_TRANSPORT_SERVICE_CONFIG_H */
diff --git a/src/core/lib/transport/transport_op_string.c b/src/core/lib/transport/transport_op_string.c
index 0259fa23eb..b36e4f22d0 100644
--- a/src/core/lib/transport/transport_op_string.c
+++ b/src/core/lib/transport/transport_op_string.c
@@ -49,10 +49,12 @@
 
 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, GPR_DUMP_HEX | GPR_DUMP_ASCII));
+  gpr_strvec_add(
+      b, grpc_dump_slice(GRPC_MDKEY(md), GPR_DUMP_HEX | GPR_DUMP_ASCII));
 
   gpr_strvec_add(b, gpr_strdup(" value="));
-  gpr_strvec_add(b, grpc_dump_slice(md->value, GPR_DUMP_HEX | GPR_DUMP_ASCII));
+  gpr_strvec_add(
+      b, grpc_dump_slice(GRPC_MDVALUE(md), GPR_DUMP_HEX | GPR_DUMP_ASCII));
 }
 
 static void put_metadata_list(gpr_strvec *b, grpc_metadata_batch md) {