On 10/15/2018 03:58 PM, Markus Armbruster wrote:
Fei Li <f...@suse.com> writes:
Add a new Error parameter for vnc_display_init() to handle errors
in its caller: vnc_init_func(), just like vnc_display_open() does.
And let its callees propagate the Error, like init_keyboard_layout().
Signed-off-by: Fei Li <f...@suse.com>
---
include/ui/console.h | 2 +-
ui/curses.c | 4 +++-
ui/keymaps.c | 11 ++++++-----
ui/keymaps.h | 2 +-
ui/sdl.c | 4 +++-
ui/vnc.c | 16 +++++++++++-----
6 files changed, 25 insertions(+), 14 deletions(-)
diff --git a/include/ui/console.h b/include/ui/console.h
index fb969caf70..c17803c530 100644
--- a/include/ui/console.h
+++ b/include/ui/console.h
@@ -453,7 +453,7 @@ void qemu_display_early_init(DisplayOptions *opts);
void qemu_display_init(DisplayState *ds, DisplayOptions *opts);
/* vnc.c */
-void vnc_display_init(const char *id);
+void vnc_display_init(const char *id, Error **errp);
void vnc_display_open(const char *id, Error **errp);
void vnc_display_add_client(const char *id, int csock, bool skipauth);
int vnc_display_password(const char *id, const char *password);
diff --git a/ui/curses.c b/ui/curses.c
index 59d819fd4d..60c0962334 100644
--- a/ui/curses.c
+++ b/ui/curses.c
@@ -28,6 +28,7 @@
#include <termios.h>
#endif
+#include "qapi/error.h"
#include "qemu-common.h"
#include "ui/console.h"
#include "ui/input.h"
@@ -421,7 +422,8 @@ static void curses_keyboard_setup(void)
keyboard_layout = "en-us";
#endif
if(keyboard_layout) {
- kbd_layout = init_keyboard_layout(name2keysym, keyboard_layout);
+ kbd_layout = init_keyboard_layout(name2keysym, keyboard_layout,
+ &error_fatal);
if (!kbd_layout)
exit(1);
As Philippe pointed out, this exit() is now unreachable.
Right, should be deleted along with the below one.
}
diff --git a/ui/keymaps.c b/ui/keymaps.c
index 43fe604724..52d432e856 100644
--- a/ui/keymaps.c
+++ b/ui/keymaps.c
@@ -27,6 +27,7 @@
#include "sysemu/sysemu.h"
#include "trace.h"
#include "qemu/error-report.h"
+#include "qapi/error.h"
struct keysym2code {
uint32_t count;
@@ -81,7 +82,7 @@ static void add_keysym(char *line, int keysym, int keycode,
kbd_layout_t *k)
static kbd_layout_t *parse_keyboard_layout(const name2keysym_t *table,
const char *language,
`> - kbd_layout_t *k)
+ kbd_layout_t *k, Error **errp)
{
FILE *f;
char * filename;
@@ -94,7 +95,7 @@ static kbd_layout_t *parse_keyboard_layout(const
name2keysym_t *table,
f = filename ? fopen(filename, "r") : NULL;
g_free(filename);
if (!f) {
- fprintf(stderr, "Could not read keymap file: '%s'\n", language);
+ error_setg(errp, "could not read keymap file: '%s'", language);
return NULL;
}
@@ -118,7 +119,7 @@ static kbd_layout_t *parse_keyboard_layout(const name2keysym_t *table,
continue;
}
if (!strncmp(line, "include ", 8)) {
- parse_keyboard_layout(table, line + 8, k);
+ parse_keyboard_layout(table, line + 8, k, errp);
Lacks error checking.
Before this patch, an error in an included file is reported to stderr,
but is otherwise ignored:
$ cat kbd-layout
include bad
include worse
$ qemu-system-x86_64 -nodefaults -S -monitor stdio -display vnc=:0 -k
kbd-layout
QEMU 3.0.50 monitor - type 'help' for more information
(qemu) Could not read keymap file: 'bad'
Could not read keymap file: 'worse'
Afterwards, the error gets stored in errp. If a second include fails,
we attempt to store another one, which fails the error_setv()'s
assertion:
$ qemu-system-x86_64 -nodefaults -S -display vnc=:0 -k kbd-layout
qemu-system-x86_64: /work/armbru/qemu/util/error.c:57: error_setv:
Assertion `*errp == NULL' failed.
Aborted (core dumped)
If it's the only failed include, parse_keyboard_layout() sets an error
and returns succes, which is a no-no. Callers using the return value to
determine success are prone to leak the error, or run into
error_setv()'s assertion. Callers using the error are prone to leak the
returned kbd_layout_t.
Oh, sorry! My fault.. I mistook the passed errp in
parse_keyboard_layout() for &error_fatal,
in this case once the first fails, qemu will exit(1) directly and no
second include will be read.
But the truth is we use a *local_err=NULL in vnc_init_func to propagate
to the &error_abort.
Let's address this in a separate patch before this one.
if (!parse_keyboard_layout(table, line + 8, k, errp))
Ok.
I have another thought, that is pass the &error_fatal directly to
vnc_display_init/open(),
and exit() in the callee parse_keyboard_layout. But the side effect is
drooping the obvious
error message: "Failed to init/start VNC server: ".
} else {
int offset = 0;
while (line[offset] != 0 &&
@@ -170,9 +171,9 @@ static kbd_layout_t *parse_keyboard_layout(const
name2keysym_t *table,
kbd_layout_t *init_keyboard_layout(const name2keysym_t *table,
- const char *language)
+ const char *language, Error **errp)
{
- return parse_keyboard_layout(table, language, NULL);
+ return parse_keyboard_layout(table, language, NULL, errp);
}
diff --git a/ui/keymaps.h b/ui/keymaps.h
index 0693588225..98213a4191 100644
--- a/ui/keymaps.h
+++ b/ui/keymaps.h
@@ -53,7 +53,7 @@ typedef struct {
typedef struct kbd_layout_t kbd_layout_t;
kbd_layout_t *init_keyboard_layout(const name2keysym_t *table,
- const char *language);
+ const char *language, Error **errp);
int keysym2scancode(kbd_layout_t *k, int keysym,
bool shift, bool altgr, bool ctrl);
int keycode_is_keypad(kbd_layout_t *k, int keycode);
diff --git a/ui/sdl.c b/ui/sdl.c
index a5fd503c25..b33df70f4d 100644
--- a/ui/sdl.c
+++ b/ui/sdl.c
@@ -29,6 +29,7 @@
#include <SDL.h>
#include <SDL_syswm.h>
+#include "qapi/error.h"
#include "qemu-common.h"
#include "qemu/cutils.h"
#include "ui/console.h"
@@ -917,7 +918,8 @@ static void sdl1_display_init(DisplayState *ds,
DisplayOptions *o)
keyboard_layout = "en-us";
#endif
if(keyboard_layout) {
- kbd_layout = init_keyboard_layout(name2keysym, keyboard_layout);
+ kbd_layout = init_keyboard_layout(name2keysym, keyboard_layout,
+ &error_fatal);
if (!kbd_layout)
exit(1);
Again, exit() is now unreachable.
Yes.
}
diff --git a/ui/vnc.c b/ui/vnc.c
index cf221c83cc..03c70b16f6 100644
--- a/ui/vnc.c
+++ b/ui/vnc.c
@@ -3205,7 +3205,7 @@ static const DisplayChangeListenerOps dcl_ops = {
.dpy_cursor_define = vnc_dpy_cursor_define,
};
-void vnc_display_init(const char *id)
+void vnc_display_init(const char *id, Error **errp)
{
VncDisplay *vd;
@@ -3222,13 +3222,14 @@ void vnc_display_init(const char *id)
if (keyboard_layout) {
trace_vnc_key_map_init(keyboard_layout);
- vd->kbd_layout = init_keyboard_layout(name2keysym, keyboard_layout);
+ vd->kbd_layout = init_keyboard_layout(name2keysym,
+ keyboard_layout, errp);
} else {
- vd->kbd_layout = init_keyboard_layout(name2keysym, "en-us");
+ vd->kbd_layout = init_keyboard_layout(name2keysym, "en-us", errp);
}
if (!vd->kbd_layout) {
- exit(1);
+ return;
}
vd->share_policy = VNC_SHARE_POLICY_ALLOW_EXCLUSIVE;
@@ -4079,7 +4080,12 @@ int vnc_init_func(void *opaque, QemuOpts *opts, Error
**errp)
char *id = (char *)qemu_opts_id(opts);
assert(id);
- vnc_display_init(id);
+ vnc_display_init(id, &local_err);
+ if (local_err) {
+ error_prepend(&local_err, "Failed to init VNC server: ");
+ error_propagate(errp, local_err);
+ return -1;
+ }
Works, but is inconsistent with the handling of vnc_display_open()
errors, visible below. Let's match that, and convert both to
error_propagate() in a followup patch.
vnc_display_open(id, &local_err);
if (local_err != NULL) {
error_reportf_err(local_err, "Failed to start VNC server: ");
I think the easiest way forward is for me to pick a touched up version
of this patch into a v2 of my "Replace some unwise uses of
error_report() & friends" series. You'll receive a copy, of course.
Thanks!
Deal, that will be consistent and much easier. :)
Have a nice day, thanks
Fei
