qga: throw an Error in ga_channel_open()

Allow for a single point of error reporting, and further refactoring.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20220525144140.591926-8-marcandre.lureau@redhat.com>

qga/channel-posix.c

@@ -119,7 +119,7 @@ static int ga_channel_client_add(GAChannel *c, int fd)
 }
 
 static gboolean ga_channel_open(GAChannel *c, const gchar *path,
-                                GAChannelMethod method, int fd)
+                                GAChannelMethod method, int fd, Error **errp)
 {
     int ret;
     c->method = method;
@@ -133,21 +133,20 @@ static gboolean ga_channel_open(GAChannel *c, const gchar *path,
 #endif
                            );
         if (fd == -1) {
-            g_critical("error opening channel: %s", strerror(errno));
+            error_setg_errno(errp, errno, "error opening channel");
             return false;
         }
 #ifdef CONFIG_SOLARIS
         ret = ioctl(fd, I_SETSIG, S_OUTPUT | S_INPUT | S_HIPRI);
         if (ret == -1) {
-            g_critical("error setting event mask for channel: %s",
-                       strerror(errno));
+            error_setg_errno(errp, errno, "error setting event mask for channel");
             close(fd);
             return false;
         }
 #endif
         ret = ga_channel_client_add(c, fd);
         if (ret) {
-            g_critical("error adding channel to main loop");
+            error_setg(errp, "error adding channel to main loop");
             close(fd);
             return false;
         }
@@ -159,7 +158,7 @@ static gboolean ga_channel_open(GAChannel *c, const gchar *path,
         assert(fd < 0);
         fd = qemu_open_old(path, O_RDWR | O_NOCTTY | O_NONBLOCK);
         if (fd == -1) {
-            g_critical("error opening channel: %s", strerror(errno));
+            error_setg_errno(errp, errno, "error opening channel");
             return false;
         }
         tcgetattr(fd, &tio);
@@ -180,20 +179,16 @@ static gboolean ga_channel_open(GAChannel *c, const gchar *path,
         tcsetattr(fd, TCSANOW, &tio);
         ret = ga_channel_client_add(c, fd);
         if (ret) {
-            g_critical("error adding channel to main loop");
+            error_setg(errp, "error adding channel to main loop");
             close(fd);
             return false;
         }
         break;
     }
     case GA_CHANNEL_UNIX_LISTEN: {
         if (fd < 0) {
-            Error *local_err = NULL;
-
-            fd = unix_listen(path, &local_err);
-            if (local_err != NULL) {
-                g_critical("%s", error_get_pretty(local_err));
-                error_free(local_err);
+            fd = unix_listen(path, errp);
+            if (fd < 0) {
                 return false;
             }
         }
@@ -202,32 +197,27 @@ static gboolean ga_channel_open(GAChannel *c, const gchar *path,
     }
     case GA_CHANNEL_VSOCK_LISTEN: {
         if (fd < 0) {
-            Error *local_err = NULL;
             SocketAddress *addr;
             char *addr_str;
 
             addr_str = g_strdup_printf("vsock:%s", path);
-            addr = socket_parse(addr_str, &local_err);
+            addr = socket_parse(addr_str, errp);
             g_free(addr_str);
-            if (local_err != NULL) {
-                g_critical("%s", error_get_pretty(local_err));
-                error_free(local_err);
+            if (!addr) {
                 return false;
             }
 
-            fd = socket_listen(addr, 1, &local_err);
+            fd = socket_listen(addr, 1, errp);
             qapi_free_SocketAddress(addr);
-            if (local_err != NULL) {
-                g_critical("%s", error_get_pretty(local_err));
-                error_free(local_err);
+            if (fd < 0) {
                 return false;
             }
         }
         ga_channel_listen_add(c, fd, true);
         break;
     }
     default:
-        g_critical("error binding/listening to specified socket");
+        error_setg(errp, "error binding/listening to specified socket");
         return false;
     }
 
@@ -272,12 +262,14 @@ GIOStatus ga_channel_read(GAChannel *c, gchar *buf, gsize size, gsize *count)
 GAChannel *ga_channel_new(GAChannelMethod method, const gchar *path,
                           int listen_fd, GAChannelCallback cb, gpointer opaque)
 {
+    Error *err = NULL;
     GAChannel *c = g_new0(GAChannel, 1);
     c->event_cb = cb;
     c->user_data = opaque;
 
-    if (!ga_channel_open(c, path, method, listen_fd)) {
-        g_critical("error opening channel");
+    if (!ga_channel_open(c, path, method, listen_fd, &err)) {
+        g_critical("%s", error_get_pretty(err));
+        error_free(err);
         ga_channel_free(c);
         return NULL;
     }