Allow overriding httpcli behavior by tests.

Change on 2014/12/17 by ctiller <ctiller@google.com>
-------------
Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=82379331

src/core/httpcli/httpcli.c

@@ -62,6 +62,9 @@ typedef struct {
   void *user_data;
 } internal_request;
 
+static grpc_httpcli_get_override g_get_override = NULL;
+static grpc_httpcli_post_override g_post_override = NULL;
+
 static void next_address(internal_request *req);
 
 static void finish(internal_request *req, int success) {
@@ -217,7 +220,12 @@ static void on_resolved(void *arg, grpc_resolved_addresses *addresses) {
 void grpc_httpcli_get(const grpc_httpcli_request *request,
                       gpr_timespec deadline,
                       grpc_httpcli_response_cb on_response, void *user_data) {
-  internal_request *req = gpr_malloc(sizeof(internal_request));
+  internal_request *req;
+  if (g_get_override &&
+      g_get_override(request, deadline, on_response, user_data)) {
+    return;
+  }
+  req = gpr_malloc(sizeof(internal_request));
   memset(req, 0, sizeof(*req));
   req->request_text = grpc_httpcli_format_get_request(request);
   grpc_httpcli_parser_init(&req->parser);
@@ -237,7 +245,12 @@ void grpc_httpcli_post(const grpc_httpcli_request *request,
                        const char *body_bytes, size_t body_size,
                        gpr_timespec deadline,
                        grpc_httpcli_response_cb on_response, void *user_data) {
-  internal_request *req = gpr_malloc(sizeof(internal_request));
+  internal_request *req;
+  if (g_post_override && g_post_override(request, body_bytes, body_size,
+                                         deadline, on_response, user_data)) {
+    return;
+  }
+  req = gpr_malloc(sizeof(internal_request));
   memset(req, 0, sizeof(*req));
   req->request_text =
       grpc_httpcli_format_post_request(request, body_bytes, body_size);
@@ -253,3 +266,9 @@ void grpc_httpcli_post(const grpc_httpcli_request *request,
   grpc_resolve_address(request->host, req->use_ssl ? "https" : "http",
                        on_resolved, req);
 }
+
+void grpc_httpcli_set_override(grpc_httpcli_get_override get,
+                               grpc_httpcli_post_override post) {
+  g_get_override = get;
+  g_post_override = post;
+}

src/core/httpcli/httpcli.h

@@ -100,4 +100,19 @@ void grpc_httpcli_post(const grpc_httpcli_request *request,
                        gpr_timespec deadline,
                        grpc_httpcli_response_cb on_response, void *user_data);
 
+/* override functions return 1 if they handled the request, 0 otherwise */
+typedef int (*grpc_httpcli_get_override)(const grpc_httpcli_request *request,
+                                         gpr_timespec deadline,
+                                         grpc_httpcli_response_cb on_response,
+                                         void *user_data);
+typedef int (*grpc_httpcli_post_override)(const grpc_httpcli_request *request,
+                                          const char *body_bytes,
+                                          size_t body_size,
+                                          gpr_timespec deadline,
+                                          grpc_httpcli_response_cb on_response,
+                                          void *user_data);
+
+void grpc_httpcli_set_override(grpc_httpcli_get_override get,
+                               grpc_httpcli_post_override post);
+
 #endif  /* __GRPC_INTERNAL_HTTPCLI_HTTPCLI_H__ */