json: use cleanup functions

Use cleanup attributes from cleanup.h to avoid boilerplate cleanup code.
Introduce _cleanup_tokener_ to call json_tokener_free() on cleanup.

Signed-off-by: Caleb Sander <csander@purestorage.com>

diff --git a/src/nvme/json.c b/src/nvme/json.c
index 7a5a69e5deb21c802ac5379fe1e4f95c43248f28..4d0f9875fcc071b2625cd4c09adb59294c0c2cf1 100644 (file)
--- a/src/nvme/json.c
+++ b/src/nvme/json.c
@@ -14,6 +14,7 @@
 
 #include <json.h>
 
+#include "cleanup.h"
 #include "fabrics.h"
 #include "log.h"
 #include "private.h"
@@ -189,31 +190,34 @@ static void json_parse_host(nvme_root_t r, struct json_object *host_obj)
        }
 }
 
+static DEFINE_CLEANUP_FUNC(cleanup_tokener, json_tokener *, json_tokener_free)
+#define _cleanup_tokener_ __cleanup__(cleanup_tokener)
+
 static struct json_object *parse_json(nvme_root_t r, int fd)
 {
        char buf[JSON_FILE_BUF_SIZE];
-       struct json_object *obj = NULL;
+       struct json_object *obj;
        char *str = NULL;
-       json_tokener *tok = NULL;
+       _cleanup_tokener_ json_tokener *tok = NULL;
        int ret;
-       void *ptr = NULL;
+       _cleanup_free_ void *ptr = NULL;
        int len = 0;
 
        while ((ret = read(fd, buf, JSON_FILE_BUF_SIZE)) > 0) {
                str = realloc(ptr, len + ret);
                if (!str)
-                       goto out;
+                       return NULL;
                memcpy(&str[len], buf, ret);
                len += ret;
                ptr = str;
        }
 
        if (ret < 0 || !len)
-               goto out;
+               return NULL;
 
        tok = json_tokener_new_ex(JSON_TOKENER_DEFAULT_DEPTH);
        if (!tok)
-               goto out;
+               return NULL;
 
        /* Enforce correctly formatted JSON */
        tok->flags = JSON_TOKENER_STRICT;
@@ -222,10 +226,6 @@ static struct json_object *parse_json(nvme_root_t r, int fd)
        if (!obj)
                nvme_msg(r, LOG_DEBUG, "JSON parsing failed: %s\n",
                         json_util_get_last_err());
-out:
-       if (tok)
-               json_tokener_free(tok);
-       free(ptr);
 
        return obj;
 }
@@ -335,21 +335,21 @@ static void json_update_port(struct json_object *ctrl_array, nvme_ctrl_t c)
         * Store the keyring description in the JSON config file.
         */
        if (cfg->keyring) {
-               char *desc = nvme_describe_key_serial(cfg->keyring);
+               _cleanup_free_ char *desc =
+                       nvme_describe_key_serial(cfg->keyring);
 
                if (desc) {
                        json_object_object_add(port_obj, "keyring",
                                               json_object_new_string(desc));
-                       free(desc);
                }
        }
        if (cfg->tls_key) {
-               char *desc = nvme_describe_key_serial(cfg->tls_key);
+               _cleanup_free_ char *desc =
+                       nvme_describe_key_serial(cfg->tls_key);
 
                if (desc) {
                        json_object_object_add(port_obj, "tls_key",
                                               json_object_new_string(desc));
-                       free(desc);
                }
        }