ui/vnc.c: polish vnc_init_func

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 <[email protected]>

---
  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(-)

include/ui/console.h +1 -1

index fb969caf70..c17803c530 100644
@@ -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);

ui/curses.c +3 -1

index 59d819fd4d..60c0962334 100644
@@ -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);
      }

ui/keymaps.c +6 -5

index 43fe604724..52d432e856 100644
@@ -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);
          } 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);
  }
 
 

ui/keymaps.h +1 -1

index 0693588225..98213a4191 100644
@@ -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);

ui/sdl.c +3 -1

index a5fd503c25..b33df70f4d 100644
@@ -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);
      }

ui/vnc.c +11 -5

index cf221c83cc..03c70b16f6 100644
@@ -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;
+    }
      vnc_display_open(id, &local_err);
      if (local_err != NULL) {
          error_reportf_err(local_err, "Failed to start VNC server: ");

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 <[email protected]>

---
 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(-)

include/ui/console.h +1 -1

index fb969caf70..c17803c530 100644
@@ -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);

ui/curses.c +1 -0

index 59d819fd4d..60c0962334 100644
@@ -28,6 +28,7 @@
 #include <termios.h>
 #endif
 
+#include "qapi/error.h"
 #include "qemu-common.h"
 #include "ui/console.h"
 #include "ui/input.h"

ui/curses.c +0 -0

     }

ui/keymaps.c +6 -5

index 43fe604724..52d432e856 100644
@@ -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);
         } 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);
 }
 
 

ui/keymaps.h +1 -1

index 0693588225..98213a4191 100644
@@ -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);

ui/sdl.c +3 -1

index a5fd503c25..b33df70f4d 100644
@@ -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);
     }

ui/vnc.c +11 -5

index cf221c83cc..03c70b16f6 100644
@@ -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;
+    }
     vnc_display_open(id, &local_err);
     if (local_err != NULL) {
         error_reportf_err(local_err, "Failed to start VNC server: ");

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 <[email protected]>

---
 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(-)

include/ui/console.h +1 -1

index fb969caf70..c17803c530 100644
@@ -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);

ui/curses.c +1 -0

index 59d819fd4d..60c0962334 100644
@@ -28,6 +28,7 @@
 #include <termios.h>
 #endif
 
+#include "qapi/error.h"
 #include "qemu-common.h"
 #include "ui/console.h"
 #include "ui/input.h"

ui/curses.c +0 -0

     }

ui/keymaps.c +1 -0

index 43fe604724..52d432e856 100644
@@ -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;

ui/keymaps.c +2 -1

+                                           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;
     }
 

ui/keymaps.c +2 -2

         } 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);
 }
 
 

ui/keymaps.h +1 -1

index 0693588225..98213a4191 100644
@@ -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);

ui/sdl.c +1 -0

index a5fd503c25..b33df70f4d 100644
@@ -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"

ui/sdl.c +0 -0

     }

ui/vnc.c +5 -4

index cf221c83cc..03c70b16f6 100644
@@ -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;

Quoted 35 lines · Fei Li

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 <[email protected]>

---
  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(-)

include/ui/console.h +1 -1

index fb969caf70..c17803c530 100644
@@ -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);

ui/curses.c +0 -0

index 59d819fd4d..60c0962334 100644
@@ -28,6 +28,7 @@
  #include <termios.h>
  #endif
 

ui/curses.c static void curses_keyboard_setup(void) · line 428

Quoted 13 lines

ui/curses.c +3 -1

+#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.

Quoted 15 lines

ui/curses.c +0 -0

      }

ui/keymaps.c +1 -0

index 43fe604724..52d432e856 100644
@@ -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;

ui/keymaps.c static void add_keysym(char *line, int keysym, int keycode, kbd_layout_t *k) · line 84

Quoted 3 lines

ui/keymaps.c +0 -0

@@ -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)

Quoted 14 lines

ui/keymaps.c +2 -1

+                                           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;
      }
 

ui/keymaps.c static kbd_layout_t *parse_keyboard_layout(const name2keysym_t *table, · line 122

Quoted 5 lines

ui/keymaps.c +1 -1

@@ -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.

Let's address this in a separate patch before this one.

if (!parse_keyboard_layout(table, line + 8, k, errp))

Quoted 37 lines

ui/keymaps.c +2 -2

          } 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);
  }
 
 

ui/keymaps.h +1 -1

index 0693588225..98213a4191 100644
@@ -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);

ui/sdl.c +0 -0

index a5fd503c25..b33df70f4d 100644
@@ -29,6 +29,7 @@
  #include <SDL.h>
  #include <SDL_syswm.h>
 

ui/sdl.c static void sdl1_display_init(DisplayState *ds, DisplayOptions *o) · line 924

Quoted 13 lines

ui/sdl.c +3 -1

+#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.

Quoted 33 lines

ui/sdl.c +0 -0

      }

ui/vnc.c +5 -4

index cf221c83cc..03c70b16f6 100644
@@ -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;

ui/vnc.c int vnc_init_func(void *opaque, QemuOpts *opts, Error **errp) · line 4088

Quoted 10 lines

ui/vnc.c +6 -1

@@ -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.

ui/vnc.c int vnc_init_func(void *opaque, QemuOpts *opts, Error **errp) · line 4091

Quoted 3 lines

ui/vnc.c +0 -0

      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!