Merge remote-tracking branch 'remotes/kraxel/tags/pull-chardev-2' into staging

purge error_is_set()

# gpg: Signature made Wed 21 May 2014 11:43:44 BST using RSA key ID D3E87138
# gpg: Good signature from "Gerd Hoffmann (work) <kraxel@redhat.com>"
# gpg:                 aka "Gerd Hoffmann <gerd@kraxel.org>"
# gpg:                 aka "Gerd Hoffmann (private) <kraxel@gmail.com>"

* remotes/kraxel/tags/pull-chardev-2:
  error: error_is_set() is finally unused; remove
  char: Explain qmp_chardev_add()'s unusual error handling
  char: Clean up fragile use of error_is_set()
  char: Use return values instead of error_is_set(errp)
  qemu-socket: Clean up inet_connect_opts()
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

include/qapi/error.h

@@ -67,12 +67,6 @@ void error_set_win32(Error **errp, int win32_err, ErrorClass err_class,
  */
 void error_setg_file_open(Error **errp, int os_errno, const char *filename);
 
-/**
- * Returns true if an indirect pointer to an error is pointing to a valid
- * error object.
- */
-bool error_is_set(Error **errp);
-
 /*
  * Get the error class of an error object.
  */

qemu-char.c

@@ -3204,6 +3204,7 @@ CharDriverState *qemu_chr_new_from_opts(QemuOpts *opts,
                                     void (*init)(struct CharDriverState *s),
                                     Error **errp)
 {
+    Error *local_err = NULL;
     CharDriver *cd;
     CharDriverState *chr;
     GSList *i;
@@ -3245,13 +3246,14 @@ CharDriverState *qemu_chr_new_from_opts(QemuOpts *opts,
         chr = NULL;
         backend->kind = cd->kind;
         if (cd->parse) {
-            cd->parse(opts, backend, errp);
-            if (error_is_set(errp)) {
+            cd->parse(opts, backend, &local_err);
+            if (local_err) {
+                error_propagate(errp, local_err);
                 goto qapi_out;
             }
         }
         ret = qmp_chardev_add(bid ? bid : id, backend, errp);
-        if (error_is_set(errp)) {
+        if (!ret) {
             goto qapi_out;
         }
 
@@ -3263,7 +3265,7 @@ CharDriverState *qemu_chr_new_from_opts(QemuOpts *opts,
             backend->kind = CHARDEV_BACKEND_KIND_MUX;
             backend->mux->chardev = g_strdup(bid);
             ret = qmp_chardev_add(id, backend, errp);
-            if (error_is_set(errp)) {
+            if (!ret) {
                 chr = qemu_chr_find(bid);
                 qemu_chr_delete(chr);
                 chr = NULL;
@@ -3620,18 +3622,18 @@ static int qmp_chardev_open_file_source(char *src, int flags,
 
 static CharDriverState *qmp_chardev_open_file(ChardevFile *file, Error **errp)
 {
-    int flags, in = -1, out = -1;
+    int flags, in = -1, out;
 
     flags = O_WRONLY | O_TRUNC | O_CREAT | O_BINARY;
     out = qmp_chardev_open_file_source(file->out, flags, errp);
-    if (error_is_set(errp)) {
+    if (out < 0) {
         return NULL;
     }
 
     if (file->has_in) {
         flags = O_RDONLY;
         in = qmp_chardev_open_file_source(file->in, flags, errp);
-        if (error_is_set(errp)) {
+        if (in < 0) {
             qemu_close(out);
             return NULL;
         }
@@ -3647,7 +3649,7 @@ static CharDriverState *qmp_chardev_open_serial(ChardevHostdev *serial,
     int fd;
 
     fd = qmp_chardev_open_file_source(serial->device, O_RDWR, errp);
-    if (error_is_set(errp)) {
+    if (fd < 0) {
         return NULL;
     }
     qemu_set_nonblock(fd);
@@ -3665,7 +3667,7 @@ static CharDriverState *qmp_chardev_open_parallel(ChardevHostdev *parallel,
     int fd;
 
     fd = qmp_chardev_open_file_source(parallel->device, O_RDWR, errp);
-    if (error_is_set(errp)) {
+    if (fd < 0) {
         return NULL;
     }
     return qemu_chr_open_pp_fd(fd);
@@ -3692,7 +3694,7 @@ static CharDriverState *qmp_chardev_open_socket(ChardevSocket *sock,
     } else {
         fd = socket_connect(addr, errp, NULL, NULL);
     }
-    if (error_is_set(errp)) {
+    if (fd < 0) {
         return NULL;
     }
     return qemu_chr_open_socket_fd(fd, do_nodelay, is_listen,
@@ -3705,7 +3707,7 @@ static CharDriverState *qmp_chardev_open_udp(ChardevUdp *udp,
     int fd;
 
     fd = socket_dgram(udp->remote, udp->local, errp);
-    if (error_is_set(errp)) {
+    if (fd < 0) {
         return NULL;
     }
     return qemu_chr_open_udp_fd(fd);
@@ -3796,7 +3798,13 @@ ChardevReturn *qmp_chardev_add(const char *id, ChardevBackend *backend,
         break;
     }
 
-    if (chr == NULL && !error_is_set(errp)) {
+    /*
+     * Character backend open hasn't been fully converted to the Error
+     * API.  Some opens fail without setting an error.  Set a generic
+     * error then.
+     * TODO full conversion to Error API
+     */
+    if (chr == NULL && errp && !*errp) {
         error_setg(errp, "Failed to create chardev");
     }
     if (chr) {

util/error.c

@@ -142,11 +142,6 @@ Error *error_copy(const Error *err)
     return err_new;
 }
 
-bool error_is_set(Error **errp)
-{
-    return (errp && *errp);
-}
-
 ErrorClass error_get_class(const Error *err)
 {
     return err->err_class;

util/qemu-sockets.c

@@ -354,6 +354,7 @@ static struct addrinfo *inet_parse_connect_opts(QemuOpts *opts, Error **errp)
 int inet_connect_opts(QemuOpts *opts, Error **errp,
                       NonBlockingConnectHandler *callback, void *opaque)
 {
+    Error *local_err = NULL;
     struct addrinfo *res, *e;
     int sock = -1;
     bool in_progress;
@@ -372,24 +373,27 @@ int inet_connect_opts(QemuOpts *opts, Error **errp,
     }
 
     for (e = res; e != NULL; e = e->ai_next) {
-        if (error_is_set(errp)) {
-            error_free(*errp);
-            *errp = NULL;
-        }
+        error_free(local_err);
+        local_err = NULL;
         if (connect_state != NULL) {
             connect_state->current_addr = e;
         }
-        sock = inet_connect_addr(e, &in_progress, connect_state, errp);
-        if (in_progress) {
-            return sock;
-        } else if (sock >= 0) {
-            /* non blocking socket immediate success, call callback */
-            if (callback != NULL) {
-                callback(sock, opaque);
-            }
+        sock = inet_connect_addr(e, &in_progress, connect_state, &local_err);
+        if (sock >= 0) {
             break;
         }
     }
+
+    if (sock < 0) {
+        error_propagate(errp, local_err);
+    } else if (in_progress) {
+        /* wait_for_connect() will do the rest */
+        return sock;
+    } else {
+        if (callback) {
+            callback(sock, opaque);
+        }
+    }
     g_free(connect_state);
     freeaddrinfo(res);
     return sock;