cmd_results_to_json: return copied string and properly free the json

The only user of this function would copy the string right away
to get rid of the const flag anyway, and freeing a const string
afterwards might work but is not meant to be done according to the
json-c API.

3 files changed, 8 insertions, 9 deletions

diff --git a/include/sway/commands.h b/include/sway/commands.h
index 7ca0bda8..6d17144a 100644
--- a/include/sway/commands.h
+++ b/include/sway/commands.h
@@ -79,7 +79,7 @@ void free_cmd_results(struct cmd_results *results);
  *
  * Free the JSON string later on.
  */
-const char *cmd_results_to_json(struct cmd_results *results);
+char *cmd_results_to_json(struct cmd_results *results);
 
 struct cmd_results *add_color(const char *name,
                 char *buffer, const char *color);
diff --git a/sway/commands.c b/sway/commands.c
index 5b67e1ec..ef477f38 100644
--- a/sway/commands.c
+++ b/sway/commands.c
@@ -527,7 +527,7 @@ void free_cmd_results(struct cmd_results *results) {
         free(results);
 }
 
-const char *cmd_results_to_json(struct cmd_results *results) {
+char *cmd_results_to_json(struct cmd_results *results) {
         json_object *result_array = json_object_new_array();
         json_object *root = json_object_new_object();
         json_object_object_add(root, "success",
@@ -542,9 +542,9 @@ const char *cmd_results_to_json(struct cmd_results *results) {
         }
         json_object_array_add(result_array, root);
         const char *json = json_object_to_json_string(result_array);
-        free(result_array);
-        free(root);
-        return json;
+        char *res = strdup(json);
+        json_object_put(result_array);
+        return res;
 }
 
 /**
diff --git a/sway/ipc-server.c b/sway/ipc-server.c
index 01b80b05..96889b39 100644
--- a/sway/ipc-server.c
+++ b/sway/ipc-server.c
@@ -481,11 +481,10 @@ void ipc_client_handle_command(struct ipc_client *client) {
         case IPC_COMMAND:
         {
                 struct cmd_results *results = execute_command(buf, NULL);
-                const char *json = cmd_results_to_json(results);
-                char reply[256];
-                int length = snprintf(reply, sizeof(reply), "%s", json);
+                char *json = cmd_results_to_json(results);
+                int length = strlen(json);
+                client_valid = ipc_send_reply(client, json, (uint32_t)length);
                 free(json);
-                client_valid = ipc_send_reply(client, reply, (uint32_t)length);
                 free_cmd_results(results);
                 goto exit_cleanup;
         }