Adding option to add a null terminator when loading a file.

- This will take care of a potential issue with default credentials
  where the slice pointer is casted as const char * for APIs that need a
  null terminated string.

3 files changed, 22 insertions, 7 deletions

diff --git a/test/core/security/create_jwt.c b/test/core/security/create_jwt.c
index 614dd1e50c..b02469fb35 100644
--- a/test/core/security/create_jwt.c
+++ b/test/core/security/create_jwt.c
@@ -48,7 +48,7 @@ void create_jwt(const char *json_key_file_path, const char *service_url,
   grpc_auth_json_key key;
   int ok = 0;
   char *jwt;
-  gpr_slice json_key_data = gpr_load_file(json_key_file_path, &ok);
+  gpr_slice json_key_data = gpr_load_file(json_key_file_path, 1, &ok);
   if (!ok) {
     fprintf(stderr, "Could not read %s.\n", json_key_file_path);
     exit(1);
diff --git a/test/core/security/fetch_oauth2.c b/test/core/security/fetch_oauth2.c
index cc847c82f7..7a40fe0dbb 100644
--- a/test/core/security/fetch_oauth2.c
+++ b/test/core/security/fetch_oauth2.c
@@ -77,7 +77,7 @@ static void on_oauth2_response(void *user_data, grpc_mdelem **md_elems,
 static grpc_credentials *create_service_account_creds(
     const char *json_key_file_path, const char *scope) {
   int success;
-  gpr_slice json_key = gpr_load_file(json_key_file_path, &success);
+  gpr_slice json_key = gpr_load_file(json_key_file_path, 1, &success);
   if (!success) {
     gpr_log(GPR_ERROR, "Could not read file %s.", json_key_file_path);
     exit(1);
@@ -91,7 +91,7 @@ static grpc_credentials *create_refresh_token_creds(
     const char *json_refresh_token_file_path) {
   int success;
   gpr_slice refresh_token =
-      gpr_load_file(json_refresh_token_file_path, &success);
+      gpr_load_file(json_refresh_token_file_path, 1, &success);
   if (!success) {
     gpr_log(GPR_ERROR, "Could not read file %s.", json_refresh_token_file_path);
     exit(1);
diff --git a/test/core/support/file_test.c b/test/core/support/file_test.c
index dd8caf7a80..56e7a4948e 100644
--- a/test/core/support/file_test.c
+++ b/test/core/support/file_test.c
@@ -49,6 +49,7 @@ static const char prefix[] = "file_test";
 static void test_load_empty_file(void) {
   FILE *tmp = NULL;
   gpr_slice slice;
+  gpr_slice slice_with_null_term;
   int success;
   char *tmp_name;
 
@@ -59,13 +60,19 @@ static void test_load_empty_file(void) {
   GPR_ASSERT(tmp != NULL);
   fclose(tmp);
 
-  slice = gpr_load_file(tmp_name, &success);
+  slice = gpr_load_file(tmp_name, 0, &success);
   GPR_ASSERT(success == 1);
   GPR_ASSERT(GPR_SLICE_LENGTH(slice) == 0);
 
+  slice_with_null_term = gpr_load_file(tmp_name, 1, &success);
+  GPR_ASSERT(success == 1);
+  GPR_ASSERT(GPR_SLICE_LENGTH(slice_with_null_term) == 1);
+  GPR_ASSERT(GPR_SLICE_START_PTR(slice_with_null_term)[0] == 0);
+
   remove(tmp_name);
   gpr_free(tmp_name);
   gpr_slice_unref(slice);
+  gpr_slice_unref(slice_with_null_term);
 }
 
 static void test_load_failure(void) {
@@ -82,7 +89,7 @@ static void test_load_failure(void) {
   fclose(tmp);
   remove(tmp_name);
 
-  slice = gpr_load_file(tmp_name, &success);
+  slice = gpr_load_file(tmp_name, 0, &success);
   GPR_ASSERT(success == 0);
   GPR_ASSERT(GPR_SLICE_LENGTH(slice) == 0);
   gpr_free(tmp_name);
@@ -92,6 +99,7 @@ static void test_load_failure(void) {
 static void test_load_small_file(void) {
   FILE *tmp = NULL;
   gpr_slice slice;
+  gpr_slice slice_with_null_term;
   int success;
   char *tmp_name;
   const char *blah = "blah";
@@ -104,14 +112,21 @@ static void test_load_small_file(void) {
   GPR_ASSERT(fwrite(blah, 1, strlen(blah), tmp) == strlen(blah));
   fclose(tmp);
 
-  slice = gpr_load_file(tmp_name, &success);
+  slice = gpr_load_file(tmp_name, 0, &success);
   GPR_ASSERT(success == 1);
   GPR_ASSERT(GPR_SLICE_LENGTH(slice) == strlen(blah));
   GPR_ASSERT(!memcmp(GPR_SLICE_START_PTR(slice), blah, strlen(blah)));
 
+  slice_with_null_term = gpr_load_file(tmp_name, 1, &success);
+  GPR_ASSERT(success == 1);
+  GPR_ASSERT(GPR_SLICE_LENGTH(slice_with_null_term) == (strlen(blah) + 1));
+  GPR_ASSERT(strcmp((const char *)GPR_SLICE_START_PTR(slice_with_null_term),
+                    blah) == 0);
+
   remove(tmp_name);
   gpr_free(tmp_name);
   gpr_slice_unref(slice);
+  gpr_slice_unref(slice_with_null_term);
 }
 
 static void test_load_big_file(void) {
@@ -135,7 +150,7 @@ static void test_load_big_file(void) {
   GPR_ASSERT(fwrite(buffer, 1, sizeof(buffer), tmp) == sizeof(buffer));
   fclose(tmp);
 
-  slice = gpr_load_file(tmp_name, &success);
+  slice = gpr_load_file(tmp_name, 0, &success);
   GPR_ASSERT(success == 1);
   GPR_ASSERT(GPR_SLICE_LENGTH(slice) == sizeof(buffer));
   current = GPR_SLICE_START_PTR(slice);