Re: [Qemu-devel] [PATCH v2 04/10] vnc: switch to QemuOpts, allow multiple servers

[Gonglei <arei.gonglei@huawei.com>]

On 2014/12/10 17:37, Gerd Hoffmann wrote:

> This patch switches vnc over to QemuOpts, and it (more or less
> as side effect) allows multiple vnc server instances.
> 
> Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
> ---
>  include/ui/console.h |   4 +-
>  qmp.c                |  15 ++-
>  ui/vnc.c             | 271 ++++++++++++++++++++++++++++++++-------------------
>  vl.c                 |  42 +++-----
>  4 files changed, 200 insertions(+), 132 deletions(-)
> 
> diff --git a/include/ui/console.h b/include/ui/console.h
> index 5ff2e27..887ed91 100644
> --- a/include/ui/console.h
> +++ b/include/ui/console.h
> @@ -328,12 +328,14 @@ void cocoa_display_init(DisplayState *ds, int full_screen);
>  
>  /* vnc.c */
>  void vnc_display_init(const char *id);
> -void vnc_display_open(const char *id, const char *display, Error **errp);
> +void vnc_display_open(const char *id, Error **errp);
>  void vnc_display_add_client(const char *id, int csock, bool skipauth);
>  char *vnc_display_local_addr(const char *id);
>  #ifdef CONFIG_VNC
>  int vnc_display_password(const char *id, const char *password);
>  int vnc_display_pw_expire(const char *id, time_t expires);
> +QemuOpts *vnc_parse_func(const char *str);
> +int vnc_init_func(QemuOpts *opts, void *opaque);
>  #else
>  static inline int vnc_display_password(const char *id, const char *password)
>  {
> diff --git a/qmp.c b/qmp.c
> index 0b4f131..3fda973 100644
> --- a/qmp.c
> +++ b/qmp.c
> @@ -368,7 +368,20 @@ void qmp_change_vnc_password(const char *password, Error **errp)
>  
>  static void qmp_change_vnc_listen(const char *target, Error **errp)
>  {
> -    vnc_display_open(NULL, target, errp);
> +    QemuOptsList *olist = qemu_find_opts("vnc");
> +    QemuOpts *opts;
> +
> +    if (strstr(target, "id=")) {
> +        error_setg(errp, "id not supported");
> +        return;
> +    }
> +
> +    opts = qemu_opts_find(olist, "default");
> +    if (opts) {
> +        qemu_opts_del(opts);
> +    }
> +    opts = vnc_parse_func(target);
> +    vnc_init_func(opts, NULL);
>  }
>  
>  static void qmp_change_vnc(const char *target, bool has_arg, const char *arg,
> diff --git a/ui/vnc.c b/ui/vnc.c
> index 1b86365..cf8bed8 100644
> --- a/ui/vnc.c
> +++ b/ui/vnc.c
> @@ -31,6 +31,7 @@
>  #include "qemu/sockets.h"
>  #include "qemu/timer.h"
>  #include "qemu/acl.h"
> +#include "qemu/config-file.h"
>  #include "qapi/qmp/types.h"
>  #include "qmp-commands.h"
>  #include "qemu/osdep.h"
> @@ -2969,7 +2970,12 @@ static const DisplayChangeListenerOps dcl_ops = {
>  
>  void vnc_display_init(const char *id)
>  {
> -    VncDisplay *vs = g_malloc0(sizeof(*vs));
> +    VncDisplay *vs;
> +
> +    if (vnc_display_find(id) != NULL) {
> +        return;
> +    }
> +    vs = g_malloc0(sizeof(*vs));
>  
>      vs->id = strdup(id);
>      QTAILQ_INSERT_TAIL(&vnc_displays, vs, next);
> @@ -3065,14 +3071,65 @@ char *vnc_display_local_addr(const char *id)
>      return vnc_socket_local_addr("%s:%s", vs->lsock);
>  }
>  
> -void vnc_display_open(const char *id, const char *display, Error **errp)
> +static QemuOptsList qemu_vnc_opts = {
> +    .name = "vnc",
> +    .head = QTAILQ_HEAD_INITIALIZER(qemu_vnc_opts.head),
> +    .implied_opt_name = "vnc",
> +    .desc = {
> +        {
> +            .name = "vnc",
> +            .type = QEMU_OPT_STRING,
> +        },{
> +            .name = "websocket",
> +            .type = QEMU_OPT_STRING,
> +        },{
> +            .name = "x509",
> +            .type = QEMU_OPT_STRING,
> +        },{
> +            .name = "share",
> +            .type = QEMU_OPT_STRING,
> +        },{
> +            .name = "password",
> +            .type = QEMU_OPT_BOOL,
> +        },{
> +            .name = "reverse",
> +            .type = QEMU_OPT_BOOL,
> +        },{
> +            .name = "lock-key-sync",
> +            .type = QEMU_OPT_BOOL,
> +        },{
> +            .name = "sasl",
> +            .type = QEMU_OPT_BOOL,
> +        },{
> +            .name = "tls",
> +            .type = QEMU_OPT_BOOL,
> +        },{
> +            .name = "x509verify",
> +            .type = QEMU_OPT_BOOL,
> +        },{
> +            .name = "acl",
> +            .type = QEMU_OPT_BOOL,
> +        },{
> +            .name = "lossy",
> +            .type = QEMU_OPT_BOOL,
> +        },{
> +            .name = "non-adaptive",
> +            .type = QEMU_OPT_BOOL,
> +        },
> +        { /* end of list */ }
> +    },
> +};
> +
> +void vnc_display_open(const char *id, Error **errp)
>  {
>      VncDisplay *vs = vnc_display_find(id);
> -    const char *options;
> +    QemuOpts *opts = qemu_opts_find(&qemu_vnc_opts, id);
> +    const char *display, *websocket, *share;
>      int password = 0;
>      int reverse = 0;
>  #ifdef CONFIG_VNC_TLS
>      int tls = 0, x509 = 0;
> +    const char *path;
>  #endif
>  #ifdef CONFIG_VNC_SASL
>      int sasl = 0;
> @@ -3088,115 +3145,86 @@ void vnc_display_open(const char *id, const char *display, Error **errp)
>          return;
>      }
>      vnc_display_close(vs);
> -    if (strcmp(display, "none") == 0)
> -        return;
>  
> +    if (!opts) {
> +        return;
> +    }
> +    display = qemu_opt_get(opts, "vnc");
> +    if (!display || strcmp(display, "none") == 0) {
> +        return;
> +    }
>      vs->display = g_strdup(display);
> -    vs->share_policy = VNC_SHARE_POLICY_ALLOW_EXCLUSIVE;
> -
> -    options = display;
> -    while ((options = strchr(options, ','))) {
> -        options++;
> -        if (strncmp(options, "password", 8) == 0) {
> -            if (fips_get_state()) {
> -                error_setg(errp,
> -                           "VNC password auth disabled due to FIPS mode, "
> -                           "consider using the VeNCrypt or SASL authentication "
> -                           "methods as an alternative");
> -                goto fail;
> -            }
> -            password = 1; /* Require password auth */
> -        } else if (strncmp(options, "reverse", 7) == 0) {
> -            reverse = 1;
> -        } else if (strncmp(options, "no-lock-key-sync", 16) == 0) {
> -            lock_key_sync = 0;
> +
> +    password = qemu_opt_get_bool(opts, "password", false);
> +    if (password && fips_get_state()) {
> +        error_setg(errp,
> +                   "VNC password auth disabled due to FIPS mode, "
> +                   "consider using the VeNCrypt or SASL authentication "
> +                   "methods as an alternative");
> +        goto fail;
> +    }
> +
> +    reverse = qemu_opt_get_bool(opts, "reverse", false);
> +    lock_key_sync = qemu_opt_get_bool(opts, "lock-key-sync", true);
>  #ifdef CONFIG_VNC_SASL
> -        } else if (strncmp(options, "sasl", 4) == 0) {
> -            sasl = 1; /* Require SASL auth */
> +    sasl = qemu_opt_get_bool(opts, "sasl", false);
>  #endif
> -#ifdef CONFIG_VNC_WS
> -        } else if (strncmp(options, "websocket", 9) == 0) {
> -            char *start, *end;
> -            vs->websocket = 1;
> -
> -            /* Check for 'websocket=<port>' */
> -            start = strchr(options, '=');
> -            end = strchr(options, ',');
> -            if (start && (!end || (start < end))) {
> -                int len = end ? end-(start+1) : strlen(start+1);
> -                if (len < 6) {
> -                    /* extract the host specification from display */
> -                    char  *host = NULL, *port = NULL, *host_end = NULL;
> -                    port = g_strndup(start + 1, len);
> -
> -                    /* ipv6 hosts have colons */
> -                    end = strchr(display, ',');
> -                    host_end = g_strrstr_len(display, end - display, ":");
> -
> -                    if (host_end) {
> -                        host = g_strndup(display, host_end - display + 1);
> -                    } else {
> -                        host = g_strndup(":", 1);
> -                    }
> -                    vs->ws_display = g_strconcat(host, port, NULL);
> -                    g_free(host);
> -                    g_free(port);
> -                }
> -            }
> -#endif /* CONFIG_VNC_WS */
>  #ifdef CONFIG_VNC_TLS
> -        } else if (strncmp(options, "tls", 3) == 0) {
> -            tls = 1; /* Require TLS */
> -        } else if (strncmp(options, "x509", 4) == 0) {
> -            char *start, *end;
> -            x509 = 1; /* Require x509 certificates */
> -            if (strncmp(options, "x509verify", 10) == 0)
> -                vs->tls.x509verify = 1; /* ...and verify client certs */
> -
> -            /* Now check for 'x509=/some/path' postfix
> -             * and use that to setup x509 certificate/key paths */
> -            start = strchr(options, '=');
> -            end = strchr(options, ',');
> -            if (start && (!end || (start < end))) {
> -                int len = end ? end-(start+1) : strlen(start+1);
> -                char *path = g_strndup(start + 1, len);
> -
> -                VNC_DEBUG("Trying certificate path '%s'\n", path);
> -                if (vnc_tls_set_x509_creds_dir(vs, path) < 0) {
> -                    error_setg(errp, "Failed to find x509 certificates/keys in %s", path);
> -                    g_free(path);
> -                    goto fail;
> -                }
> -                g_free(path);
> -            } else {
> -                error_setg(errp, "No certificate path provided");
> -                goto fail;
> -            }
> +    tls  = qemu_opt_get_bool(opts, "tls", false);
> +    path = qemu_opt_get(opts, "x509");
> +    if (path) {
> +        x509 = 1;
> +        vs->tls.x509verify = qemu_opt_get_bool(opts, "x509verify", false);
> +        if (vnc_tls_set_x509_creds_dir(vs, path) < 0) {
> +            error_setg(errp, "Failed to find x509 certificates/keys in %s",
> +                       path);
> +            goto fail;
> +        }
> +    }
>  #endif
>  #if defined(CONFIG_VNC_TLS) || defined(CONFIG_VNC_SASL)
> -        } else if (strncmp(options, "acl", 3) == 0) {
> -            acl = 1;
> -#endif
> -        } else if (strncmp(options, "lossy", 5) == 0) {
> -#ifdef CONFIG_VNC_JPEG
> -            vs->lossy = true;
> +    acl = qemu_opt_get_bool(opts, "acl", false);
>  #endif
> -        } else if (strncmp(options, "non-adaptive", 12) == 0) {
> -            vs->non_adaptive = true;
> -        } else if (strncmp(options, "share=", 6) == 0) {
> -            if (strncmp(options+6, "ignore", 6) == 0) {
> -                vs->share_policy = VNC_SHARE_POLICY_IGNORE;
> -            } else if (strncmp(options+6, "allow-exclusive", 15) == 0) {
> -                vs->share_policy = VNC_SHARE_POLICY_ALLOW_EXCLUSIVE;
> -            } else if (strncmp(options+6, "force-shared", 12) == 0) {
> -                vs->share_policy = VNC_SHARE_POLICY_FORCE_SHARED;
> -            } else {
> -                error_setg(errp, "unknown vnc share= option");
> -                goto fail;
> -            }
> +
> +    share = qemu_opt_get(opts, "share");
> +    if (share) {
> +        if (strcmp(share, "ignore") == 0) {
> +            vs->share_policy = VNC_SHARE_POLICY_IGNORE;
> +        } else if (strcmp(share, "allow-exclusive") == 0) {
> +            vs->share_policy = VNC_SHARE_POLICY_ALLOW_EXCLUSIVE;
> +        } else if (strcmp(share, "force-shared") == 0) {
> +            vs->share_policy = VNC_SHARE_POLICY_FORCE_SHARED;
> +        } else {
> +            error_setg(errp, "unknown vnc share= option");
> +            goto fail;
> +        }
> +    } else {
> +        vs->share_policy = VNC_SHARE_POLICY_ALLOW_EXCLUSIVE;
> +    }
> +
> + #ifdef CONFIG_VNC_WS
> +    websocket = qemu_opt_get(opts, "websocket");
> +    if (websocket) {
> +        /* extract the host specification from display */
> +        char  *host = NULL, *host_end = NULL;
> +        vs->websocket = 1;
> +
> +        /* ipv6 hosts have colons */
> +        host_end = strrchr(display, ':');
> +        if (host_end) {
> +            host = g_strndup(display, host_end - display + 1);
> +        } else {
> +            host = g_strdup(":");
>          }
> +        vs->ws_display = g_strconcat(host, websocket, NULL);
> +        g_free(host);
>      }
> +#endif /* CONFIG_VNC_WS */
>  
> +#ifdef CONFIG_VNC_JPEG
> +    vs->lossy = qemu_opt_get_bool(opts, "lossy", false);
> +#endif
> +    vs->non_adaptive = qemu_opt_get_bool(opts, "non-adaptive", false);
>      /* adaptive updates are only used with tight encoding and
>       * if lossy updates are enabled so we can disable all the
>       * calculations otherwise */
> @@ -3407,3 +3435,44 @@ void vnc_display_add_client(const char *id, int csock, bool skipauth)
>      }
>      vnc_connect(vs, csock, skipauth, false);
>  }
> +
> +QemuOpts *vnc_parse_func(const char *str)
> +{
> +    return qemu_opts_parse(qemu_find_opts("vnc"), str, 1);
> +}
> +
> +int vnc_init_func(QemuOpts *opts, void *opaque)
> +{
> +    Error *local_err = NULL;
> +    QemuOptsList *olist = qemu_find_opts("vnc");
> +    char *id = (char *)qemu_opts_id(opts);
> +
> +    if (!id) {
> +        /* auto-assign id if not present */
> +        int i = 2;
> +        id = g_strdup("default");
> +        while (qemu_opts_find(olist, id)) {
> +            g_free(id);
> +            id = g_strdup_printf("vnc%d", i++);
> +        }
> +        qemu_opts_set_id(opts, id);
> +    }
> +    fprintf(stderr, "%s: id \"%s\"\n", __func__, id);

A debug message, isn't it?

> +
> +    vnc_display_init(id);
> +    vnc_display_open(id, &local_err);
> +    if (local_err != NULL) {
> +        error_report("Failed to start VNC server on `%s': %s",
> +                     qemu_opt_get(opts, "display"),
> +                     error_get_pretty(local_err));
> +        error_free(local_err);
> +        exit(1);

Now, this function is called by main() and qmp_change_vnc_listen() ,
That's ok for main() exit if encounter any errors, but don't adapt to qmp
command IMHO.

Regards,
-Gonglei

> +    }
> +    return 0;
> +}
> +
> +static void vnc_register_config(void)
> +{
> +    qemu_add_opts(&qemu_vnc_opts);
> +}
> +machine_init(vnc_register_config);
> diff --git a/vl.c b/vl.c
> index 08b73ee..0bf00cf 100644
> --- a/vl.c
> +++ b/vl.c
> @@ -158,9 +158,6 @@ int smp_cpus = 1;
>  int max_cpus = 0;
>  int smp_cores = 1;
>  int smp_threads = 1;
> -#ifdef CONFIG_VNC
> -const char *vnc_display;
> -#endif
>  int acpi_enabled = 1;
>  int no_hpet = 0;
>  int fd_bootchk = 1;
> @@ -2087,16 +2084,12 @@ static DisplayType select_display(const char *p)
>  #endif
>      } else if (strstart(p, "vnc", &opts)) {
>  #ifdef CONFIG_VNC
> -        display_remote++;
> -
> -        if (*opts) {
> -            const char *nextopt;
> -
> -            if (strstart(opts, "=", &nextopt)) {
> -                vnc_display = nextopt;
> +        if (*opts == '=') {
> +            display_remote++;
> +            if (vnc_parse_func(opts+1) == NULL) {
> +                exit(1);
>              }
> -        }
> -        if (!vnc_display) {
> +        } else {
>              fprintf(stderr, "VNC requires a display argument vnc=<display>\n");
>              exit(1);
>          }
> @@ -3563,7 +3556,9 @@ int main(int argc, char **argv, char **envp)
>  	    case QEMU_OPTION_vnc:
>  #ifdef CONFIG_VNC
>                  display_remote++;
> -                vnc_display = optarg;
> +                if (vnc_parse_func(optarg) == NULL) {
> +                    exit(1);
> +                }
>  #else
>                  fprintf(stderr, "VNC support is disabled\n");
>                  exit(1);
> @@ -4016,7 +4011,7 @@ int main(int argc, char **argv, char **envp)
>  #elif defined(CONFIG_SDL) || defined(CONFIG_COCOA)
>          display_type = DT_SDL;
>  #elif defined(CONFIG_VNC)
> -        vnc_display = "localhost:0,to=99";
> +        vnc_parse_func("localhost:0,to=99,id=default");
>          show_vnc_port = 1;
>  #else
>          display_type = DT_NONE;
> @@ -4321,21 +4316,10 @@ int main(int argc, char **argv, char **envp)
>  
>  #ifdef CONFIG_VNC
>      /* init remote displays */
> -    if (vnc_display) {
> -        Error *local_err = NULL;
> -        const char *id = "default";
> -        vnc_display_init(id);
> -        vnc_display_open(id, vnc_display, &local_err);
> -        if (local_err != NULL) {
> -            error_report("Failed to start VNC server on `%s': %s",
> -                         vnc_display, error_get_pretty(local_err));
> -            error_free(local_err);
> -            exit(1);
> -        }
> -
> -        if (show_vnc_port) {
> -            printf("VNC server running on `%s'\n", vnc_display_local_addr(id));
> -        }
> +    qemu_opts_foreach(qemu_find_opts("vnc"), vnc_init_func, NULL, 0);
> +    if (show_vnc_port) {
> +        printf("VNC server running on `%s'\n",
> +               vnc_display_local_addr("default"));
>      }
>  #endif
>  #ifdef CONFIG_SPICE