From 057054f665f02bcda1155f0e637c265cf01b3b3e Mon Sep 17 00:00:00 2001
From: David Garcia Quintas <dgq@google.com>
Date: Thu, 31 Mar 2016 09:20:42 -0700
Subject: [PATCH] Added grpc_uri_get_query_arg per comments.

---
 src/core/lib/client_config/uri_parser.c   | 12 ++++++++++++
 src/core/lib/client_config/uri_parser.h   |  4 ++++
 test/core/client_config/uri_parser_test.c |  5 +++++
 3 files changed, 21 insertions(+)

diff --git a/src/core/lib/client_config/uri_parser.c b/src/core/lib/client_config/uri_parser.c
index d818d4c4d1a..dfcd623e849 100644
--- a/src/core/lib/client_config/uri_parser.c
+++ b/src/core/lib/client_config/uri_parser.c
@@ -281,6 +281,18 @@ grpc_uri *grpc_uri_parse(const char *uri_text, int suppress_errors) {
   return uri;
 }
 
+const char *grpc_uri_get_query_arg(const grpc_uri *uri, const char *key) {
+  GPR_ASSERT(key != NULL);
+  if (key[0] == '\0') return NULL;
+
+  for (size_t i = 0; i < uri->num_query_parts; ++i) {
+    if (0 == strcmp(key, uri->query_parts[i])) {
+      return uri->query_parts_values[i];
+    }
+  }
+  return NULL;
+}
+
 void grpc_uri_destroy(grpc_uri *uri) {
   if (!uri) return;
   gpr_free(uri->scheme);
diff --git a/src/core/lib/client_config/uri_parser.h b/src/core/lib/client_config/uri_parser.h
index 115dd5a2f6c..b44188b8cdf 100644
--- a/src/core/lib/client_config/uri_parser.h
+++ b/src/core/lib/client_config/uri_parser.h
@@ -53,6 +53,10 @@ typedef struct {
 /** parse a uri, return NULL on failure */
 grpc_uri *grpc_uri_parse(const char *uri_text, int suppress_errors);
 
+/** return the part of a query string after the '=' in "?key=xxx&...", or NULL
+ * if key is not present */
+const char *grpc_uri_get_query_arg(const grpc_uri *uri, const char *key);
+
 /** destroy a uri */
 void grpc_uri_destroy(grpc_uri *uri);
 
diff --git a/test/core/client_config/uri_parser_test.c b/test/core/client_config/uri_parser_test.c
index bc3e01c90ab..6cb8c1d535b 100644
--- a/test/core/client_config/uri_parser_test.c
+++ b/test/core/client_config/uri_parser_test.c
@@ -80,6 +80,11 @@ static void test_query_parts() {
     GPR_ASSERT(0 == strcmp("", uri->query_parts[3]));
     GPR_ASSERT(NULL == uri->query_parts_values[3]);
 
+    GPR_ASSERT(NULL == grpc_uri_get_query_arg(uri, "a"));
+    GPR_ASSERT(0 == strcmp("B", grpc_uri_get_query_arg(uri, "b")));
+    GPR_ASSERT(0 == strcmp("", grpc_uri_get_query_arg(uri, "c")));
+    GPR_ASSERT(NULL == grpc_uri_get_query_arg(uri, ""));
+
     GPR_ASSERT(0 == strcmp("frag", uri->fragment));
     grpc_uri_destroy(uri);
   }