Spawn external programs asynchronously

Drawback is that we can't check the exitcode anymore.
But we were unsure why/when we need this, see:
https://github.com/profanity-im/profanity/pull/1760/files#r980868708

Fixes https://github.com/profanity-im/profanity/issues/1759

src/command/cmd_funcs.c

@@ -9424,7 +9424,7 @@ _url_external_method(const char* cmd_template, const char* url, const char* file
 {
     gchar** argv = format_call_external_argv(cmd_template, url, filename);
 
-    if (!call_external(argv, NULL, NULL)) {
+    if (!call_external(argv)) {
         cons_show_error("Unable to call external executable for url: check the logs for more information.");
     } else {
         cons_show("URL '%s' has been called with '%s'.", url, cmd_template);

src/common.c

@@ -443,44 +443,25 @@ get_mentions(gboolean whole_word, gboolean case_sensitive, const char* const mes
 }
 
 gboolean
-call_external(gchar** argv, gchar** std_out, gchar** std_err)
+call_external(gchar** argv)
 {
-    GError* spawn_error = NULL;
+    GError* spawn_error;
-    GError* exit_error = NULL;
     gboolean is_successful;
-    gint wait_status;
 
-    GSpawnFlags flags = G_SPAWN_SEARCH_PATH;
+    GSpawnFlags flags = G_SPAWN_SEARCH_PATH | G_SPAWN_STDOUT_TO_DEV_NULL | G_SPAWN_STDERR_TO_DEV_NULL;
-    if (std_out == NULL)
-        flags |= G_SPAWN_STDOUT_TO_DEV_NULL;
-    if (std_err == NULL)
-        flags |= G_SPAWN_STDERR_TO_DEV_NULL;
-
-    is_successful = g_spawn_sync(NULL, // Inherit the parent PWD.
-                                 argv,
-                                 NULL, // Inherit the parent environment.
-                                 flags,
-                                 NULL, NULL, // No func. before exec() in child.
-                                 std_out, std_err,
-                                 &wait_status, &spawn_error);
 
+    is_successful = g_spawn_async(NULL, // Inherit the parent PWD
+                                  argv,
+                                  NULL, // Inherit the parent environment
+                                  flags,
+                                  NULL, NULL, NULL,
+                                  &spawn_error);
     if (!is_successful) {
         gchar* cmd = g_strjoinv(" ", argv);
-        log_error("Spawning '%s' failed with with error '%s'", cmd, spawn_error ? spawn_error->message : "Unknown, spawn_error is NULL");
+        log_error("Spawning '%s' failed with error '%s'", cmd, spawn_error ? spawn_error->message : "Unknown, spawn_error is NULL");
-        ;
 
         g_error_free(spawn_error);
         g_free(cmd);
-    } else {
-        is_successful = g_spawn_check_exit_status(wait_status, &exit_error);
-
-        if (!is_successful) {
-            gchar* cmd = g_strjoinv(" ", argv);
-            log_error("'%s' exited with error '%s'", cmd, exit_error->message);
-
-            g_error_free(exit_error);
-            g_free(cmd);
-        }
     }
 
     return is_successful;

src/common.h

@@ -103,7 +103,7 @@ void get_file_paths_recursive(const char* directory, GSList** contents);
 
 char* get_random_string(int length);
 
-gboolean call_external(gchar** argv, gchar** std_out, gchar** std_err);
+gboolean call_external(gchar** argv);
 gchar** format_call_external_argv(const char* template, const char* url, const char* filename);
 
 gchar* unique_filename_from_url(const char* url, const char* path);

src/tools/aesgcm_download.c

@@ -155,7 +155,7 @@ aesgcm_file_get(void* userdata)
                                                  aesgcm_dl->filename);
 
         // TODO: Log the error.
-        if (!call_external(argv, NULL, NULL)) {
+        if (!call_external(argv)) {
             http_print_transfer_update(aesgcm_dl->window, aesgcm_dl->url,
                                        "Downloading '%s' failed: Unable to call "
                                        "command '%s' with file at '%s' (%s).",

src/tools/http_download.c

@@ -202,7 +202,7 @@ http_file_get(void* userdata)
                                                  download->filename);
 
         // TODO: Log the error.
-        if (!call_external(argv, NULL, NULL)) {
+        if (!call_external(argv)) {
             http_print_transfer_update(download->window, download->url,
                                        "Downloading '%s' failed: Unable to call "
                                        "command '%s' with file at '%s' (%s).",

src/xmpp/avatar.c

@@ -346,7 +346,7 @@ _avatar_request_item_result_handler(xmpp_stanza_t* const stanza, void* const use
         } else {
             gchar** argv = format_call_external_argv(cmdtemplate, NULL, filename->str);
 
-            if (!call_external(argv, NULL, NULL)) {
+            if (!call_external(argv)) {
                 cons_show_error("Unable to display avatar: check the logs for more information.");
             }