vnc: add display-update monitor command.

screendump: add png support.
 vmsvga: screen update fix.
 i386: sev setup for -bios loaded firmware
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Merge tag 'kraxel-20220427-pull-request' of git://git.kraxel.org/qemu into staging

vnc: add display-update monitor command.
screendump: add png support.
vmsvga: screen update fix.
i386: sev setup for -bios loaded firmware

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# -----END PGP SIGNATURE-----
# gpg: Signature made Wed 27 Apr 2022 10:29:41 AM PDT
# gpg:                using RSA key A0328CFFB93A17A79901FE7D4CB6D8EED3E87138
# gpg: Good signature from "Gerd Hoffmann (work) <kraxel@redhat.com>" [undefined]
# gpg:                 aka "Gerd Hoffmann <gerd@kraxel.org>" [undefined]
# gpg:                 aka "Gerd Hoffmann (private) <kraxel@gmail.com>" [undefined]
# gpg: WARNING: This key is not certified with a trusted signature!
# gpg:          There is no indication that the signature belongs to the owner.
# Primary key fingerprint: A032 8CFF B93A 17A7 9901  FE7D 4CB6 D8EE D3E8 7138

* tag 'kraxel-20220427-pull-request' of git://git.kraxel.org/qemu:
  i386: firmware parsing and sev setup for -bios loaded firmware
  i386: factor out x86_firmware_configure()
  i386: move bios load error message
  avocado/vnc: add test_change_listen
  qapi/ui: add 'display-update' command for changing listen address
  ui/vnc: refactor arrays of addresses to SocketAddressList
  Added parameter to take screenshot with screendump as PNG
  Replacing CONFIG_VNC_PNG with CONFIG_PNG
  hw/display/vmware_vga: do not discard screen updates

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

docs/about/removed-features.rst

@@ -366,7 +366,8 @@ documentation of ``query-hotpluggable-cpus`` for additional details.
 ``change`` (removed in 6.0)
 '''''''''''''''''''''''''''
 
-Use ``blockdev-change-medium`` or ``change-vnc-password`` instead.
+Use ``blockdev-change-medium`` or ``change-vnc-password`` or
+``display-update`` instead.
 
 ``query-events`` (removed in 6.0)
 '''''''''''''''''''''''''''''''''

hmp-commands.hx

@@ -247,11 +247,12 @@ ERST
 
     {
         .name       = "screendump",
-        .args_type  = "filename:F,device:s?,head:i?",
+        .args_type  = "filename:F,format:-fs,device:s?,head:i?",
-        .params     = "filename [device [head]]",
+        .params     = "filename [-f format] [device [head]]",
-        .help       = "save screen from head 'head' of display device 'device' "
+        .help       = "save screen from head 'head' of display device 'device'"
-                      "into PPM image 'filename'",
+                      "in specified format 'format' as image 'filename'."
-        .cmd        = hmp_screendump,
+                      "Currently only 'png' and 'ppm' formats are supported.",
+         .cmd        = hmp_screendump,
         .coroutine  = true,
     },
 

hw/display/trace-events

@@ -24,6 +24,7 @@ vmware_setmode(uint32_t w, uint32_t h, uint32_t bpp) "%dx%d @ %d bpp"
 vmware_verify_rect_less_than_zero(const char *name, const char *param, int x) "%s: %s was < 0 (%d)"
 vmware_verify_rect_greater_than_bound(const char *name, const char *param, int bound, int x) "%s: %s was > %d (%d)"
 vmware_verify_rect_surface_bound_exceeded(const char *name, const char *component, int bound, const char *param1, int value1, const char *param2, int value2) "%s: %s > %d (%s: %d, %s: %d)"
+vmware_update_rect_delayed_flush(void) "display update FIFO full - forcing flush"
 
 # virtio-gpu-base.c
 virtio_gpu_features(bool virgl) "virgl %d"

hw/display/vmware_vga.c

@@ -80,7 +80,7 @@ struct vmsvga_state_s {
     struct vmsvga_rect_s {
         int x, y, w, h;
     } redraw_fifo[REDRAW_FIFO_LEN];
-    int redraw_fifo_first, redraw_fifo_last;
+    int redraw_fifo_last;
 };
 
 #define TYPE_VMWARE_SVGA "vmware-svga"
@@ -380,33 +380,39 @@ static inline void vmsvga_update_rect(struct vmsvga_state_s *s,
     dpy_gfx_update(s->vga.con, x, y, w, h);
 }
 
-static inline void vmsvga_update_rect_delayed(struct vmsvga_state_s *s,
-                int x, int y, int w, int h)
-{
-    struct vmsvga_rect_s *rect = &s->redraw_fifo[s->redraw_fifo_last++];
-
-    s->redraw_fifo_last &= REDRAW_FIFO_LEN - 1;
-    rect->x = x;
-    rect->y = y;
-    rect->w = w;
-    rect->h = h;
-}
-
 static inline void vmsvga_update_rect_flush(struct vmsvga_state_s *s)
 {
     struct vmsvga_rect_s *rect;
 
     if (s->invalidated) {
-        s->redraw_fifo_first = s->redraw_fifo_last;
+        s->redraw_fifo_last = 0;
         return;
     }
     /* Overlapping region updates can be optimised out here - if someone
      * knows a smart algorithm to do that, please share.  */
-    while (s->redraw_fifo_first != s->redraw_fifo_last) {
+    for (int i = 0; i < s->redraw_fifo_last; i++) {
-        rect = &s->redraw_fifo[s->redraw_fifo_first++];
+        rect = &s->redraw_fifo[i];
-        s->redraw_fifo_first &= REDRAW_FIFO_LEN - 1;
         vmsvga_update_rect(s, rect->x, rect->y, rect->w, rect->h);
     }
+
+    s->redraw_fifo_last = 0;
+}
+
+static inline void vmsvga_update_rect_delayed(struct vmsvga_state_s *s,
+                int x, int y, int w, int h)
+{
+
+    if (s->redraw_fifo_last >= REDRAW_FIFO_LEN) {
+        trace_vmware_update_rect_delayed_flush();
+        vmsvga_update_rect_flush(s);
+    }
+
+    struct vmsvga_rect_s *rect = &s->redraw_fifo[s->redraw_fifo_last++];
+
+    rect->x = x;
+    rect->y = y;
+    rect->w = w;
+    rect->h = h;
 }
 
 #ifdef HW_RECT_ACCEL
@@ -1161,7 +1167,6 @@ static void vmsvga_reset(DeviceState *dev)
     s->config = 0;
     s->svgaid = SVGA_ID;
     s->cursor.on = 0;
-    s->redraw_fifo_first = 0;
     s->redraw_fifo_last = 0;
     s->syncing = 0;
 

hw/i386/pc_sysfw.c

@@ -147,7 +147,6 @@ static void pc_system_flash_map(PCMachineState *pcms,
     MemoryRegion *flash_mem;
     void *flash_ptr;
     int flash_size;
-    int ret;
 
     assert(PC_MACHINE_GET_CLASS(pcms)->pci_enabled);
 
@@ -195,19 +194,7 @@ static void pc_system_flash_map(PCMachineState *pcms,
             if (sev_enabled()) {
                 flash_ptr = memory_region_get_ram_ptr(flash_mem);
                 flash_size = memory_region_size(flash_mem);
-                /*
+                x86_firmware_configure(flash_ptr, flash_size);
-                 * OVMF places a GUIDed structures in the flash, so
-                 * search for them
-                 */
-                pc_system_parse_ovmf_flash(flash_ptr, flash_size);
-
-                ret = sev_es_save_reset_vector(flash_ptr, flash_size);
-                if (ret) {
-                    error_report("failed to locate and/or save reset vector");
-                    exit(1);
-                }
-
-                sev_encrypt_flash(flash_ptr, flash_size, &error_fatal);
             }
         }
     }
@@ -259,3 +246,24 @@ void pc_system_firmware_init(PCMachineState *pcms,
 
     pc_system_flash_cleanup_unused(pcms);
 }
+
+void x86_firmware_configure(void *ptr, int size)
+{
+    int ret;
+
+    /*
+     * OVMF places a GUIDed structures in the flash, so
+     * search for them
+     */
+    pc_system_parse_ovmf_flash(ptr, size);
+
+    if (sev_enabled()) {
+        ret = sev_es_save_reset_vector(ptr, size);
+        if (ret) {
+            error_report("failed to locate and/or save reset vector");
+            exit(1);
+        }
+
+        sev_encrypt_flash(ptr, size, &error_fatal);
+    }
+}

hw/i386/x86.c

@@ -1115,14 +1115,25 @@ void x86_bios_rom_init(MachineState *ms, const char *default_firmware,
     }
     bios = g_malloc(sizeof(*bios));
     memory_region_init_ram(bios, NULL, "pc.bios", bios_size, &error_fatal);
-    if (!isapc_ram_fw) {
+    if (sev_enabled()) {
-        memory_region_set_readonly(bios, true);
+        /*
-    }
+         * The concept of a "reset" simply doesn't exist for
-    ret = rom_add_file_fixed(bios_name, (uint32_t)(-bios_size), -1);
+         * confidential computing guests, we have to destroy and
-    if (ret != 0) {
+         * re-launch them instead.  So there is no need to register
-    bios_error:
+         * the firmware as rom to properly re-initialize on reset.
-        fprintf(stderr, "qemu: could not load PC BIOS '%s'\n", bios_name);
+         * Just go for a straight file load instead.
-        exit(1);
+         */
+        void *ptr = memory_region_get_ram_ptr(bios);
+        load_image_size(filename, ptr, bios_size);
+        x86_firmware_configure(ptr, bios_size);
+    } else {
+        if (!isapc_ram_fw) {
+            memory_region_set_readonly(bios, true);
+        }
+        ret = rom_add_file_fixed(bios_name, (uint32_t)(-bios_size), -1);
+        if (ret != 0) {
+            goto bios_error;
+        }
     }
     g_free(filename);
 
@@ -1143,6 +1154,11 @@ void x86_bios_rom_init(MachineState *ms, const char *default_firmware,
     memory_region_add_subregion(rom_memory,
                                 (uint32_t)(-bios_size),
                                 bios);
+    return;
+
+bios_error:
+    fprintf(stderr, "qemu: could not load PC BIOS '%s'\n", bios_name);
+    exit(1);
 }
 
 bool x86_machine_is_smm_enabled(const X86MachineState *x86ms)

include/hw/i386/x86.h

@@ -140,4 +140,7 @@ void gsi_handler(void *opaque, int n, int level);
 void ioapic_init_gsi(GSIState *gsi_state, const char *parent_name);
 DeviceState *ioapic_init_secondary(GSIState *gsi_state);
 
+/* pc_sysfw.c */
+void x86_firmware_configure(void *ptr, int size);
+
 #endif

include/ui/console.h

@@ -518,6 +518,7 @@ int vnc_display_pw_expire(const char *id, time_t expires);
 void vnc_parse(const char *str);
 int vnc_init_func(void *opaque, QemuOpts *opts, Error **errp);
 bool vnc_display_reload_certs(const char *id,  Error **errp);
+bool vnc_display_update(DisplayUpdateOptionsVNC *arg, Error **errp);
 
 /* input.c */
 int index_from_key(const char *key, size_t key_length);

meson.build

@@ -1115,14 +1115,16 @@ if gtkx11.found()
   x11 = dependency('x11', method: 'pkg-config', required: gtkx11.found(),
                    kwargs: static_kwargs)
 endif
-vnc = not_found
 png = not_found
+if get_option('png').allowed() and have_system
+   png = dependency('libpng', required: get_option('png'),
+                    method: 'pkg-config', kwargs: static_kwargs)
+endif
+vnc = not_found
 jpeg = not_found
 sasl = not_found
 if get_option('vnc').allowed() and have_system
   vnc = declare_dependency() # dummy dependency
-  png = dependency('libpng', required: get_option('vnc_png'),
-                   method: 'pkg-config', kwargs: static_kwargs)
   jpeg = dependency('libjpeg', required: get_option('vnc_jpeg'),
                     method: 'pkg-config', kwargs: static_kwargs)
   sasl = cc.find_library('sasl2', has_headers: ['sasl/sasl.h'],
@@ -1554,9 +1556,9 @@ config_host_data.set('CONFIG_TPM', have_tpm)
 config_host_data.set('CONFIG_USB_LIBUSB', libusb.found())
 config_host_data.set('CONFIG_VDE', vde.found())
 config_host_data.set('CONFIG_VHOST_USER_BLK_SERVER', have_vhost_user_blk_server)
+config_host_data.set('CONFIG_PNG', png.found())
 config_host_data.set('CONFIG_VNC', vnc.found())
 config_host_data.set('CONFIG_VNC_JPEG', jpeg.found())
-config_host_data.set('CONFIG_VNC_PNG', png.found())
 config_host_data.set('CONFIG_VNC_SASL', sasl.found())
 config_host_data.set('CONFIG_VIRTFS', have_virtfs)
 config_host_data.set('CONFIG_VTE', vte.found())
@@ -3667,11 +3669,11 @@ summary_info += {'curses support':    curses}
 summary_info += {'virgl support':     virgl}
 summary_info += {'curl support':      curl}
 summary_info += {'Multipath support': mpathpersist}
+summary_info += {'PNG support':       png}
 summary_info += {'VNC support':       vnc}
 if vnc.found()
   summary_info += {'VNC SASL support':  sasl}
   summary_info += {'VNC JPEG support':  jpeg}
-  summary_info += {'VNC PNG support':   png}
 endif
 if targetos not in ['darwin', 'haiku', 'windows']
   summary_info += {'OSS support':     oss}

meson_options.txt

@@ -177,12 +177,12 @@ option('vde', type : 'feature', value : 'auto',
        description: 'vde network backend support')
 option('virglrenderer', type : 'feature', value : 'auto',
        description: 'virgl rendering support')
+option('png', type : 'feature', value : 'auto',
+       description: 'PNG support with libpng')
 option('vnc', type : 'feature', value : 'auto',
        description: 'VNC server')
 option('vnc_jpeg', type : 'feature', value : 'auto',
        description: 'JPEG lossy compression for VNC server')
-option('vnc_png', type : 'feature', value : 'auto',
-       description: 'PNG compression for VNC server')
 option('vnc_sasl', type : 'feature', value : 'auto',
        description: 'SASL authentication for VNC server')
 option('vte', type : 'feature', value : 'auto',

monitor/hmp-cmds.c

@@ -1722,9 +1722,19 @@ hmp_screendump(Monitor *mon, const QDict *qdict)
     const char *filename = qdict_get_str(qdict, "filename");
     const char *id = qdict_get_try_str(qdict, "device");
     int64_t head = qdict_get_try_int(qdict, "head", 0);
+    const char *input_format  = qdict_get_try_str(qdict, "format");
     Error *err = NULL;
+    ImageFormat format;
 
-    qmp_screendump(filename, id != NULL, id, id != NULL, head, &err);
+    format = qapi_enum_parse(&ImageFormat_lookup, input_format,
+                              IMAGE_FORMAT_PPM, &err);
+    if (err) {
+        goto end;
+    }
+
+    qmp_screendump(filename, id != NULL, id, id != NULL, head,
+                   input_format != NULL, format, &err);
+end:
     hmp_handle_error(mon, err);
 }
 

monitor/qmp-cmds.c

@@ -346,6 +346,21 @@ void qmp_display_reload(DisplayReloadOptions *arg, Error **errp)
     }
 }
 
+void qmp_display_update(DisplayUpdateOptions *arg, Error **errp)
+{
+    switch (arg->type) {
+    case DISPLAY_UPDATE_TYPE_VNC:
+#ifdef CONFIG_VNC
+        vnc_display_update(&arg->u.vnc, errp);
+#else
+        error_setg(errp, "vnc is invalid, missing 'CONFIG_VNC'");
+#endif
+        break;
+    default:
+        abort();
+    }
+}
+
 static int qmp_x_query_rdma_foreach(Object *obj, void *opaque)
 {
     RdmaProvider *rdma;

qapi/ui.json

@@ -157,12 +157,27 @@
 ##
 { 'command': 'expire_password', 'boxed': true, 'data': 'ExpirePasswordOptions' }
 
+##
+# @ImageFormat:
+#
+# Supported image format types.
+#
+# @png: PNG format
+#
+# @ppm: PPM format
+#
+# Since: 7.1
+#
+##
+{ 'enum': 'ImageFormat',
+  'data': ['ppm', 'png'] }
+
 ##
 # @screendump:
 #
-# Write a PPM of the VGA screen to a file.
+# Capture the contents of a screen and write it to a file.
 #
-# @filename: the path of a new PPM file to store the image
+# @filename: the path of a new file to store the image
 #
 # @device: ID of the display device that should be dumped. If this parameter
 #          is missing, the primary display will be used. (Since 2.12)
@@ -171,6 +186,8 @@
 #        parameter is missing, head #0 will be used. Also note that the head
 #        can only be specified in conjunction with the device ID. (Since 2.12)
 #
+# @format: image format for screendump. (default: ppm) (Since 7.1)
+#
 # Returns: Nothing on success
 #
 # Since: 0.14
@@ -183,7 +200,8 @@
 #
 ##
 { 'command': 'screendump',
-  'data': {'filename': 'str', '*device': 'str', '*head': 'int'},
+  'data': {'filename': 'str', '*device': 'str', '*head': 'int',
+           '*format': 'ImageFormat'},
   'coroutine': true }
 
 ##
@@ -1450,3 +1468,68 @@
 { 'command': 'display-reload',
   'data': 'DisplayReloadOptions',
   'boxed' : true }
+
+##
+# @DisplayUpdateType:
+#
+# Available DisplayUpdate types.
+#
+# @vnc: VNC display
+#
+# Since: 7.1
+#
+##
+{ 'enum': 'DisplayUpdateType',
+  'data': ['vnc'] }
+
+##
+# @DisplayUpdateOptionsVNC:
+#
+# Specify the VNC reload options.
+#
+# @addresses: If specified, change set of addresses
+#             to listen for connections. Addresses configured
+#             for websockets are not touched.
+#
+# Since: 7.1
+#
+##
+{ 'struct': 'DisplayUpdateOptionsVNC',
+  'data': { '*addresses': ['SocketAddress'] } }
+
+##
+# @DisplayUpdateOptions:
+#
+# Options of the display configuration reload.
+#
+# @type: Specify the display type.
+#
+# Since: 7.1
+#
+##
+{ 'union': 'DisplayUpdateOptions',
+  'base': {'type': 'DisplayUpdateType'},
+  'discriminator': 'type',
+  'data': { 'vnc': 'DisplayUpdateOptionsVNC' } }
+
+##
+# @display-update:
+#
+# Update display configuration.
+#
+# Returns: Nothing on success.
+#
+# Since: 7.1
+#
+# Example:
+#
+# -> { "execute": "display-update",
+#      "arguments": { "type": "vnc", "addresses":
+#                     [ { "type": "inet", "host": "0.0.0.0",
+#                         "port": "5901" } ] } }
+# <- { "return": {} }
+#
+##
+{ 'command': 'display-update',
+  'data': 'DisplayUpdateOptions',
+  'boxed' : true }

scripts/ci/org.centos/stream/8/x86_64/configure

@@ -142,7 +142,7 @@
 --disable-virtiofsd \
 --disable-vnc \
 --disable-vnc-jpeg \
---disable-vnc-png \
+--disable-png \
 --disable-vnc-sasl \
 --disable-vte \
 --disable-vvfat \
@@ -200,7 +200,7 @@
 --enable-vhost-vdpa \
 --enable-vhost-vsock \
 --enable-vnc \
---enable-vnc-png \
+--enable-png \
 --enable-vnc-sasl \
 --enable-werror \
 --enable-xkbcommon

scripts/coverity-scan/run-coverity-scan

@@ -394,7 +394,7 @@ echo "Configuring..."
     --enable-opengl --enable-vte --enable-gnutls \
     --enable-nettle --enable-curses --enable-curl \
     --audio-drv-list=oss,alsa,sdl,pa --enable-virtfs \
-    --enable-vnc --enable-vnc-sasl --enable-vnc-jpeg --enable-vnc-png \
+    --enable-vnc --enable-vnc-sasl --enable-vnc-jpeg --enable-png \
     --enable-xen --enable-brlapi \
     --enable-linux-aio --enable-attr \
     --enable-cap-ng --enable-trace-backends=log --enable-spice --enable-rbd \

scripts/meson-buildoptions.sh

@@ -94,6 +94,7 @@ meson_options_help() {
   printf "%s\n" '  oss             OSS sound support'
   printf "%s\n" '  pa              PulseAudio sound support'
   printf "%s\n" '  parallels       parallels image format support'
+  printf "%s\n" '  png             PNG support with libpng'
   printf "%s\n" '  qcow1           qcow1 image format support'
   printf "%s\n" '  qed             qed image format support'
   printf "%s\n" '  qga-vss         build QGA VSS support (broken with MinGW)'
@@ -123,7 +124,6 @@ meson_options_help() {
   printf "%s\n" '  virtiofsd       build virtiofs daemon (virtiofsd)'
   printf "%s\n" '  vnc             VNC server'
   printf "%s\n" '  vnc-jpeg        JPEG lossy compression for VNC server'
-  printf "%s\n" '  vnc-png         PNG compression for VNC server'
   printf "%s\n" '  vnc-sasl        SASL authentication for VNC server'
   printf "%s\n" '  vte             vte support for the gtk UI'
   printf "%s\n" '  vvfat           vvfat image format support'
@@ -277,6 +277,8 @@ _meson_option_parse() {
     --disable-pa) printf "%s" -Dpa=disabled ;;
     --enable-parallels) printf "%s" -Dparallels=enabled ;;
     --disable-parallels) printf "%s" -Dparallels=disabled ;;
+    --enable-png) printf "%s" -Dpng=enabled ;;
+    --disable-png) printf "%s" -Dpng=disabled ;;
     --enable-profiler) printf "%s" -Dprofiler=true ;;
     --disable-profiler) printf "%s" -Dprofiler=false ;;
     --enable-qcow1) printf "%s" -Dqcow1=enabled ;;
@@ -347,8 +349,6 @@ _meson_option_parse() {
     --disable-vnc) printf "%s" -Dvnc=disabled ;;
     --enable-vnc-jpeg) printf "%s" -Dvnc_jpeg=enabled ;;
     --disable-vnc-jpeg) printf "%s" -Dvnc_jpeg=disabled ;;
-    --enable-vnc-png) printf "%s" -Dvnc_png=enabled ;;
-    --disable-vnc-png) printf "%s" -Dvnc_png=disabled ;;
     --enable-vnc-sasl) printf "%s" -Dvnc_sasl=enabled ;;
     --disable-vnc-sasl) printf "%s" -Dvnc_sasl=disabled ;;
     --enable-vte) printf "%s" -Dvte=enabled ;;

tests/avocado/vnc.py

@@ -8,9 +8,48 @@
 # This work is licensed under the terms of the GNU GPL, version 2 or
 # later.  See the COPYING file in the top-level directory.
 
+import socket
+from typing import List
+
 from avocado_qemu import QemuSystemTest
 
 
+VNC_ADDR = '127.0.0.1'
+VNC_PORT_START = 32768
+VNC_PORT_END = VNC_PORT_START + 1024
+
+
+def check_bind(port: int) -> bool:
+    with socket.socket(socket.AF_INET, socket.SOCK_STREAM) as sock:
+        try:
+            sock.bind((VNC_ADDR, port))
+        except OSError:
+            return False
+
+    return True
+
+
+def check_connect(port: int) -> bool:
+    with socket.socket(socket.AF_INET, socket.SOCK_STREAM) as sock:
+        try:
+            sock.connect((VNC_ADDR, port))
+        except ConnectionRefusedError:
+            return False
+
+    return True
+
+
+def find_free_ports(count: int) -> List[int]:
+    result = []
+    for port in range(VNC_PORT_START, VNC_PORT_END):
+        if check_bind(port):
+            result.append(port)
+            if len(result) >= count:
+                break
+    assert len(result) == count
+    return result
+
+
 class Vnc(QemuSystemTest):
     """
     :avocado: tags=vnc,quick
@@ -51,3 +90,27 @@ def test_change_password(self):
         set_password_response = self.vm.qmp('change-vnc-password',
                                             password='new_password')
         self.assertEqual(set_password_response['return'], {})
+
+    def test_change_listen(self):
+        a, b, c = find_free_ports(3)
+        self.assertFalse(check_connect(a))
+        self.assertFalse(check_connect(b))
+        self.assertFalse(check_connect(c))
+
+        self.vm.add_args('-nodefaults', '-S', '-vnc', f'{VNC_ADDR}:{a - 5900}')
+        self.vm.launch()
+        self.assertEqual(self.vm.qmp('query-vnc')['return']['service'], str(a))
+        self.assertTrue(check_connect(a))
+        self.assertFalse(check_connect(b))
+        self.assertFalse(check_connect(c))
+
+        res = self.vm.qmp('display-update', type='vnc',
+                          addresses=[{'type': 'inet', 'host': VNC_ADDR,
+                                      'port': str(b)},
+                                     {'type': 'inet', 'host': VNC_ADDR,
+                                      'port': str(c)}])
+        self.assertEqual(res['return'], {})
+        self.assertEqual(self.vm.qmp('query-vnc')['return']['service'], str(b))
+        self.assertFalse(check_connect(a))
+        self.assertTrue(check_connect(b))
+        self.assertTrue(check_connect(c))

ui/console.c

@@ -37,6 +37,9 @@
 #include "exec/memory.h"
 #include "io/channel-file.h"
 #include "qom/object.h"
+#ifdef CONFIG_PNG
+#include <png.h>
+#endif
 
 #define DEFAULT_BACKSCROLL 512
 #define CONSOLE_CURSOR_PERIOD 500
@@ -291,6 +294,89 @@ void graphic_hw_invalidate(QemuConsole *con)
     }
 }
 
+#ifdef CONFIG_PNG
+/**
+ * png_save: Take a screenshot as PNG
+ *
+ * Saves screendump as a PNG file
+ *
+ * Returns true for success or false for error.
+ *
+ * @fd: File descriptor for PNG file.
+ * @image: Image data in pixman format.
+ * @errp: Pointer to an error.
+ */
+static bool png_save(int fd, pixman_image_t *image, Error **errp)
+{
+    int width = pixman_image_get_width(image);
+    int height = pixman_image_get_height(image);
+    g_autofree png_struct *png_ptr = NULL;
+    g_autofree png_info *info_ptr = NULL;
+    g_autoptr(pixman_image_t) linebuf =
+                            qemu_pixman_linebuf_create(PIXMAN_a8r8g8b8, width);
+    uint8_t *buf = (uint8_t *)pixman_image_get_data(linebuf);
+    FILE *f = fdopen(fd, "wb");
+    int y;
+    if (!f) {
+        error_setg_errno(errp, errno,
+                         "Failed to create file from file descriptor");
+        return false;
+    }
+
+    png_ptr = png_create_write_struct(PNG_LIBPNG_VER_STRING, NULL,
+                                      NULL, NULL);
+    if (!png_ptr) {
+        error_setg(errp, "PNG creation failed. Unable to write struct");
+        fclose(f);
+        return false;
+    }
+
+    info_ptr = png_create_info_struct(png_ptr);
+
+    if (!info_ptr) {
+        error_setg(errp, "PNG creation failed. Unable to write info");
+        fclose(f);
+        png_destroy_write_struct(&png_ptr, &info_ptr);
+        return false;
+    }
+
+    png_init_io(png_ptr, f);
+
+    png_set_IHDR(png_ptr, info_ptr, width, height, 8,
+                 PNG_COLOR_TYPE_RGB_ALPHA, PNG_INTERLACE_NONE,
+                 PNG_COMPRESSION_TYPE_BASE, PNG_FILTER_TYPE_BASE);
+
+    png_write_info(png_ptr, info_ptr);
+
+    for (y = 0; y < height; ++y) {
+        qemu_pixman_linebuf_fill(linebuf, image, width, 0, y);
+        png_write_row(png_ptr, buf);
+    }
+    qemu_pixman_image_unref(linebuf);
+
+    png_write_end(png_ptr, NULL);
+
+    png_destroy_write_struct(&png_ptr, &info_ptr);
+
+    if (fclose(f) != 0) {
+        error_setg_errno(errp, errno,
+                         "PNG creation failed. Unable to close file");
+        return false;
+    }
+
+    return true;
+}
+
+#else /* no png support */
+
+static bool png_save(int fd, pixman_image_t *image, Error **errp)
+{
+    error_setg(errp, "Enable PNG support with libpng for screendump");
+    return false;
+}
+
+#endif /* CONFIG_PNG */
+
 static bool ppm_save(int fd, pixman_image_t *image, Error **errp)
 {
     int width = pixman_image_get_width(image);
@@ -329,7 +415,8 @@ static void graphic_hw_update_bh(void *con)
 /* Safety: coroutine-only, concurrent-coroutine safe, main thread only */
 void coroutine_fn
 qmp_screendump(const char *filename, bool has_device, const char *device,
-               bool has_head, int64_t head, Error **errp)
+               bool has_head, int64_t head,
+               bool has_format, ImageFormat format, Error **errp)
 {
     g_autoptr(pixman_image_t) image = NULL;
     QemuConsole *con;
@@ -385,8 +472,16 @@ qmp_screendump(const char *filename, bool has_device, const char *device,
      * yields and releases the BQL. It could produce corrupted dump, but
      * it should be otherwise safe.
      */
-    if (!ppm_save(fd, image, errp)) {
+    if (has_format && format == IMAGE_FORMAT_PNG) {
-        qemu_unlink(filename);
+        /* PNG format specified for screendump */
+        if (!png_save(fd, image, errp)) {
+            qemu_unlink(filename);
+        }
+    } else {
+        /* PPM format specified/default for screendump */
+        if (!ppm_save(fd, image, errp)) {
+            qemu_unlink(filename);
+        }
     }
 }
 

ui/vnc-enc-tight.c

@@ -32,7 +32,7 @@
    INT32 definitions between jmorecfg.h (included by jpeglib.h) and
    Win32 basetsd.h (included by windows.h). */
 
-#ifdef CONFIG_VNC_PNG
+#ifdef CONFIG_PNG
 /* The following define is needed by pngconf.h. Otherwise it won't compile,
    because setjmp.h was already included by osdep.h. */
 #define PNG_SKIP_SETJMP_CHECK
@@ -95,7 +95,7 @@ static const struct {
 };
 #endif
 
-#ifdef CONFIG_VNC_PNG
+#ifdef CONFIG_PNG
 static const struct {
     int png_zlib_level, png_filters;
 } tight_png_conf[] = {
@@ -919,7 +919,7 @@ static int send_full_color_rect(VncState *vs, int x, int y, int w, int h)
     int stream = 0;
     ssize_t bytes;
 
-#ifdef CONFIG_VNC_PNG
+#ifdef CONFIG_PNG
     if (tight_can_send_png_rect(vs, w, h)) {
         return send_png_rect(vs, x, y, w, h, NULL);
     }
@@ -966,7 +966,7 @@ static int send_mono_rect(VncState *vs, int x, int y,
     int stream = 1;
     int level = tight_conf[vs->tight->compression].mono_zlib_level;
 
-#ifdef CONFIG_VNC_PNG
+#ifdef CONFIG_PNG
     if (tight_can_send_png_rect(vs, w, h)) {
         int ret;
         int bpp = vs->client_pf.bytes_per_pixel * 8;
@@ -1020,7 +1020,7 @@ static int send_mono_rect(VncState *vs, int x, int y,
 struct palette_cb_priv {
     VncState *vs;
     uint8_t *header;
-#ifdef CONFIG_VNC_PNG
+#ifdef CONFIG_PNG
     png_colorp png_palette;
 #endif
 };
@@ -1082,7 +1082,7 @@ static int send_palette_rect(VncState *vs, int x, int y,
     int colors;
     ssize_t bytes;
 
-#ifdef CONFIG_VNC_PNG
+#ifdef CONFIG_PNG
     if (tight_can_send_png_rect(vs, w, h)) {
         return send_png_rect(vs, x, y, w, h, palette);
     }
@@ -1233,7 +1233,7 @@ static int send_jpeg_rect(VncState *vs, int x, int y, int w, int h, int quality)
 /*
  * PNG compression stuff.
  */
-#ifdef CONFIG_VNC_PNG
+#ifdef CONFIG_PNG
 static void write_png_palette(int idx, uint32_t pix, void *opaque)
 {
     struct palette_cb_priv *priv = opaque;
@@ -1379,7 +1379,7 @@ static int send_png_rect(VncState *vs, int x, int y, int w, int h,
     buffer_reset(&vs->tight->png);
     return 1;
 }
-#endif /* CONFIG_VNC_PNG */
+#endif /* CONFIG_PNG */
 
 static void vnc_tight_start(VncState *vs)
 {
@@ -1706,7 +1706,7 @@ void vnc_tight_clear(VncState *vs)
 #ifdef CONFIG_VNC_JPEG
     buffer_free(&vs->tight->jpeg);
 #endif
-#ifdef CONFIG_VNC_PNG
+#ifdef CONFIG_PNG
     buffer_free(&vs->tight->png);
 #endif
 }

ui/vnc.c

@@ -2165,7 +2165,7 @@ static void set_encodings(VncState *vs, int32_t *encodings, size_t n_encodings)
             vs->features |= VNC_FEATURE_TIGHT_MASK;
             vs->vnc_encoding = enc;
             break;
-#ifdef CONFIG_VNC_PNG
+#ifdef CONFIG_PNG
         case VNC_ENCODING_TIGHT_PNG:
             vs->features |= VNC_FEATURE_TIGHT_PNG_MASK;
             vs->vnc_encoding = enc;
@@ -3256,7 +3256,7 @@ static void vnc_connect(VncDisplay *vd, QIOChannelSocket *sioc,
 #ifdef CONFIG_VNC_JPEG
     buffer_init(&vs->tight->jpeg,     "vnc-tight-jpeg/%p", sioc);
 #endif
-#ifdef CONFIG_VNC_PNG
+#ifdef CONFIG_PNG
     buffer_init(&vs->tight->png,      "vnc-tight-png/%p", sioc);
 #endif
     buffer_init(&vs->zlib.zlib,      "vnc-zlib/%p", sioc);
@@ -3820,30 +3820,19 @@ static int vnc_display_get_address(const char *addrstr,
     return ret;
 }
 
-static void vnc_free_addresses(SocketAddress ***retsaddr,
-                               size_t *retnsaddr)
-{
-    size_t i;
-
-    for (i = 0; i < *retnsaddr; i++) {
-        qapi_free_SocketAddress((*retsaddr)[i]);
-    }
-    g_free(*retsaddr);
-
-    *retsaddr = NULL;
-    *retnsaddr = 0;
-}
-
 static int vnc_display_get_addresses(QemuOpts *opts,
                                      bool reverse,
-                                     SocketAddress ***retsaddr,
+                                     SocketAddressList **saddr_list_ret,
-                                     size_t *retnsaddr,
+                                     SocketAddressList **wsaddr_list_ret,
-                                     SocketAddress ***retwsaddr,
-                                     size_t *retnwsaddr,
                                      Error **errp)
 {
     SocketAddress *saddr = NULL;
     SocketAddress *wsaddr = NULL;
+    g_autoptr(SocketAddressList) saddr_list = NULL;
+    SocketAddressList **saddr_tail = &saddr_list;
+    SocketAddress *single_saddr = NULL;
+    g_autoptr(SocketAddressList) wsaddr_list = NULL;
+    SocketAddressList **wsaddr_tail = &wsaddr_list;
     QemuOptsIter addriter;
     const char *addr;
     int to = qemu_opt_get_number(opts, "to", 0);
@@ -3852,23 +3841,16 @@ static int vnc_display_get_addresses(QemuOpts *opts,
     bool ipv4 = qemu_opt_get_bool(opts, "ipv4", false);
     bool ipv6 = qemu_opt_get_bool(opts, "ipv6", false);
     int displaynum = -1;
-    int ret = -1;
-
-    *retsaddr = NULL;
-    *retnsaddr = 0;
-    *retwsaddr = NULL;
-    *retnwsaddr = 0;
 
     addr = qemu_opt_get(opts, "vnc");
     if (addr == NULL || g_str_equal(addr, "none")) {
-        ret = 0;
+        return 0;
-        goto cleanup;
     }
     if (qemu_opt_get(opts, "websocket") &&
         !qcrypto_hash_supports(QCRYPTO_HASH_ALG_SHA1)) {
         error_setg(errp,
                    "SHA1 hash support is required for websockets");
-        goto cleanup;
+        return -1;
     }
 
     qemu_opt_iter_init(&addriter, opts, "vnc");
@@ -3879,7 +3861,7 @@ static int vnc_display_get_addresses(QemuOpts *opts,
                                      ipv4, ipv6,
                                      &saddr, errp);
         if (rv < 0) {
-            goto cleanup;
+            return -1;
         }
         /* Historical compat - first listen address can be used
          * to set the default websocket port
@@ -3887,13 +3869,16 @@ static int vnc_display_get_addresses(QemuOpts *opts,
         if (displaynum == -1) {
             displaynum = rv;
         }
-        *retsaddr = g_renew(SocketAddress *, *retsaddr, *retnsaddr + 1);
+        QAPI_LIST_APPEND(saddr_tail, saddr);
-        (*retsaddr)[(*retnsaddr)++] = saddr;
     }
 
-    /* If we had multiple primary displays, we don't do defaults
+    if (saddr_list && !saddr_list->next) {
-     * for websocket, and require explicit config instead. */
+        single_saddr = saddr_list->value;
-    if (*retnsaddr > 1) {
+    } else {
+        /*
+         * If we had multiple primary displays, we don't do defaults
+         * for websocket, and require explicit config instead.
+         */
         displaynum = -1;
     }
 
@@ -3903,57 +3888,50 @@ static int vnc_display_get_addresses(QemuOpts *opts,
                                     has_ipv4, has_ipv6,
                                     ipv4, ipv6,
                                     &wsaddr, errp) < 0) {
-            goto cleanup;
+            return -1;
         }
 
         /* Historical compat - if only a single listen address was
          * provided, then this is used to set the default listen
          * address for websocket too
          */
-        if (*retnsaddr == 1 &&
+        if (single_saddr &&
-            (*retsaddr)[0]->type == SOCKET_ADDRESS_TYPE_INET &&
+            single_saddr->type == SOCKET_ADDRESS_TYPE_INET &&
             wsaddr->type == SOCKET_ADDRESS_TYPE_INET &&
             g_str_equal(wsaddr->u.inet.host, "") &&
-            !g_str_equal((*retsaddr)[0]->u.inet.host, "")) {
+            !g_str_equal(single_saddr->u.inet.host, "")) {
             g_free(wsaddr->u.inet.host);
-            wsaddr->u.inet.host = g_strdup((*retsaddr)[0]->u.inet.host);
+            wsaddr->u.inet.host = g_strdup(single_saddr->u.inet.host);
         }
 
-        *retwsaddr = g_renew(SocketAddress *, *retwsaddr, *retnwsaddr + 1);
+        QAPI_LIST_APPEND(wsaddr_tail, wsaddr);
-        (*retwsaddr)[(*retnwsaddr)++] = wsaddr;
     }
 
-    ret = 0;
+    *saddr_list_ret = g_steal_pointer(&saddr_list);
- cleanup:
+    *wsaddr_list_ret = g_steal_pointer(&wsaddr_list);
-    if (ret < 0) {
+    return 0;
-        vnc_free_addresses(retsaddr, retnsaddr);
-        vnc_free_addresses(retwsaddr, retnwsaddr);
-    }
-    return ret;
 }
 
 static int vnc_display_connect(VncDisplay *vd,
-                               SocketAddress **saddr,
+                               SocketAddressList *saddr_list,
-                               size_t nsaddr,
+                               SocketAddressList *wsaddr_list,
-                               SocketAddress **wsaddr,
-                               size_t nwsaddr,
                                Error **errp)
 {
     /* connect to viewer */
     QIOChannelSocket *sioc = NULL;
-    if (nwsaddr != 0) {
+    if (wsaddr_list) {
         error_setg(errp, "Cannot use websockets in reverse mode");
         return -1;
     }
-    if (nsaddr != 1) {
+    if (!saddr_list || saddr_list->next) {
         error_setg(errp, "Expected a single address in reverse mode");
         return -1;
     }
     /* TODO SOCKET_ADDRESS_TYPE_FD when fd has AF_UNIX */
-    vd->is_unix = saddr[0]->type == SOCKET_ADDRESS_TYPE_UNIX;
+    vd->is_unix = saddr_list->value->type == SOCKET_ADDRESS_TYPE_UNIX;
     sioc = qio_channel_socket_new();
     qio_channel_set_name(QIO_CHANNEL(sioc), "vnc-reverse");
-    if (qio_channel_socket_connect_sync(sioc, saddr[0], errp) < 0) {
+    if (qio_channel_socket_connect_sync(sioc, saddr_list->value, errp) < 0) {
         object_unref(OBJECT(sioc));
         return -1;
     }
@@ -3964,20 +3942,18 @@ static int vnc_display_connect(VncDisplay *vd,
 
 
 static int vnc_display_listen(VncDisplay *vd,
-                              SocketAddress **saddr,
+                              SocketAddressList *saddr_list,
-                              size_t nsaddr,
+                              SocketAddressList *wsaddr_list,
-                              SocketAddress **wsaddr,
-                              size_t nwsaddr,
                               Error **errp)
 {
-    size_t i;
+    SocketAddressList *el;
 
-    if (nsaddr) {
+    if (saddr_list) {
         vd->listener = qio_net_listener_new();
         qio_net_listener_set_name(vd->listener, "vnc-listen");
-        for (i = 0; i < nsaddr; i++) {
+        for (el = saddr_list; el; el = el->next) {
             if (qio_net_listener_open_sync(vd->listener,
-                                           saddr[i], 1,
+                                           el->value, 1,
                                            errp) < 0)  {
                 return -1;
             }
@@ -3987,12 +3963,12 @@ static int vnc_display_listen(VncDisplay *vd,
                                          vnc_listen_io, vd, NULL);
     }
 
-    if (nwsaddr) {
+    if (wsaddr_list) {
         vd->wslistener = qio_net_listener_new();
         qio_net_listener_set_name(vd->wslistener, "vnc-ws-listen");
-        for (i = 0; i < nwsaddr; i++) {
+        for (el = wsaddr_list; el; el = el->next) {
             if (qio_net_listener_open_sync(vd->wslistener,
-                                           wsaddr[i], 1,
+                                           el->value, 1,
                                            errp) < 0)  {
                 return -1;
             }
@@ -4005,13 +3981,36 @@ static int vnc_display_listen(VncDisplay *vd,
     return 0;
 }
 
+bool vnc_display_update(DisplayUpdateOptionsVNC *arg, Error **errp)
+{
+    VncDisplay *vd = vnc_display_find(NULL);
+
+    if (!vd) {
+        error_setg(errp, "Can not find vnc display");
+        return false;
+    }
+
+    if (arg->has_addresses) {
+        if (vd->listener) {
+            qio_net_listener_disconnect(vd->listener);
+            object_unref(OBJECT(vd->listener));
+            vd->listener = NULL;
+        }
+
+        if (vnc_display_listen(vd, arg->addresses, NULL, errp) < 0) {
+            return false;
+        }
+    }
+
+    return true;
+}
 
 void vnc_display_open(const char *id, Error **errp)
 {
     VncDisplay *vd = vnc_display_find(id);
     QemuOpts *opts = qemu_opts_find(&qemu_vnc_opts, id);
-    SocketAddress **saddr = NULL, **wsaddr = NULL;
+    g_autoptr(SocketAddressList) saddr_list = NULL;
-    size_t nsaddr, nwsaddr;
+    g_autoptr(SocketAddressList) wsaddr_list = NULL;
     const char *share, *device_id;
     QemuConsole *con;
     bool password = false;
@@ -4036,8 +4035,8 @@ void vnc_display_open(const char *id, Error **errp)
     }
 
     reverse = qemu_opt_get_bool(opts, "reverse", false);
-    if (vnc_display_get_addresses(opts, reverse, &saddr, &nsaddr,
+    if (vnc_display_get_addresses(opts, reverse, &saddr_list, &wsaddr_list,
-                                  &wsaddr, &nwsaddr, errp) < 0) {
+                                  errp) < 0) {
         goto fail;
     }
 
@@ -4212,16 +4211,16 @@ void vnc_display_open(const char *id, Error **errp)
     }
     qkbd_state_set_delay(vd->kbd, key_delay_ms);
 
-    if (saddr == NULL) {
+    if (saddr_list == NULL) {
-        goto cleanup;
+        return;
     }
 
     if (reverse) {
-        if (vnc_display_connect(vd, saddr, nsaddr, wsaddr, nwsaddr, errp) < 0) {
+        if (vnc_display_connect(vd, saddr_list, wsaddr_list, errp) < 0) {
             goto fail;
         }
     } else {
-        if (vnc_display_listen(vd, saddr, nsaddr, wsaddr, nwsaddr, errp) < 0) {
+        if (vnc_display_listen(vd, saddr_list, wsaddr_list, errp) < 0) {
             goto fail;
         }
     }
@@ -4230,14 +4229,11 @@ void vnc_display_open(const char *id, Error **errp)
         vnc_display_print_local_addr(vd);
     }
 
- cleanup:
+    /* Success */
-    vnc_free_addresses(&saddr, &nsaddr);
-    vnc_free_addresses(&wsaddr, &nwsaddr);
     return;
 
 fail:
     vnc_display_close(vd);
-    goto cleanup;
 }
 
 void vnc_display_add_client(const char *id, int csock, bool skipauth)

ui/vnc.h

@@ -201,7 +201,7 @@ typedef struct VncTight {
 #ifdef CONFIG_VNC_JPEG
     Buffer jpeg;
 #endif
-#ifdef CONFIG_VNC_PNG
+#ifdef CONFIG_PNG
     Buffer png;
 #endif
     int levels[4];