Re: [PATCH 13/13] ssh: add GUri-based URI parsing

["Richard W.M. Jones" <rjones@redhat.com>]

On Thu, Jul 09, 2020 at 11:42:34PM +0400, Marc-André Lureau wrote:
> Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
> ---
>  block/ssh.c | 75 +++++++++++++++++++++++++++++++++++++++++------------
>  1 file changed, 58 insertions(+), 17 deletions(-)
> 
> diff --git a/block/ssh.c b/block/ssh.c
> index c8f6ad79e3c..d2bc6277613 100644
> --- a/block/ssh.c
> +++ b/block/ssh.c
> @@ -180,9 +180,37 @@ static void sftp_error_trace(BDRVSSHState *s, const char *op)
>  
>  static int parse_uri(const char *filename, QDict *options, Error **errp)
>  {
> +    g_autofree char *port_str = NULL;
> +    const char *scheme, *server, *path, *user, *key, *value;
> +    gint port;
> +
> +#ifdef HAVE_GLIB_GURI
> +    g_autoptr(GUri) uri = NULL;
> +    g_autoptr(GHashTable) params = NULL;
> +    g_autoptr(GError) err = NULL;
> +    GHashTableIter iter;
> +
> +    uri = g_uri_parse(filename, G_URI_FLAGS_ENCODED_QUERY, &err);
> +    if (!uri) {
> +        error_setg(errp, "Failed to parse SSH URI: %s", err->message);
> +        return -EINVAL;
> +    }
> +
> +    params = g_uri_parse_params(g_uri_get_query(uri), -1,
> +                                "&;", G_URI_PARAMS_NONE, &err);
> +    if (err) {
> +        error_report("Failed to parse SSH URI query: %s", err->message);
> +        return -EINVAL;
> +    }
> +
> +    scheme = g_uri_get_scheme(uri);
> +    user = g_uri_get_user(uri);
> +    server = g_uri_get_host(uri);
> +    path = g_uri_get_path(uri);
> +    port = g_uri_get_port(uri);
> +#else
>      g_autoptr(URI) uri = NULL;
>      g_autoptr(QueryParams) qp = NULL;
> -    g_autofree char *port_str = NULL;
>      int i;

As Dan said already, this conditional code looks horrible and is going
to be a maintenance burden.  Was there a later version of this patch
series that resolved this?  I don't think I saw one.

Rich.


>      uri = uri_parse(filename);
> @@ -190,44 +218,57 @@ static int parse_uri(const char *filename, QDict *options, Error **errp)
>          return -EINVAL;
>      }
>  
> -    if (g_strcmp0(uri->scheme, "ssh") != 0) {
> -        error_setg(errp, "URI scheme must be 'ssh'");
> +    qp = query_params_parse(uri->query);
> +    if (!qp) {
> +        error_setg(errp, "could not parse query parameters");
>          return -EINVAL;
>      }
>  
> -    if (!uri->server || strcmp(uri->server, "") == 0) {
> -        error_setg(errp, "missing hostname in URI");
> +    scheme = uri->scheme;
> +    user = uri->user;
> +    server = uri->server;
> +    path = uri->path;
> +    port = uri->port;
> +#endif
> +    if (g_strcmp0(scheme, "ssh") != 0) {
> +        error_setg(errp, "URI scheme must be 'ssh'");
>          return -EINVAL;
>      }
>  
> -    if (!uri->path || strcmp(uri->path, "") == 0) {
> -        error_setg(errp, "missing remote path in URI");
> +    if (!server || strcmp(server, "") == 0) {
> +        error_setg(errp, "missing hostname in URI");
>          return -EINVAL;
>      }
>  
> -    qp = query_params_parse(uri->query);
> -    if (!qp) {
> -        error_setg(errp, "could not parse query parameters");
> +    if (!path || strcmp(path, "") == 0) {
> +        error_setg(errp, "missing remote path in URI");
>          return -EINVAL;
>      }
>  
> -    if(uri->user && strcmp(uri->user, "") != 0) {
> -        qdict_put_str(options, "user", uri->user);
> +    if (user && strcmp(user, "") != 0) {
> +        qdict_put_str(options, "user", user);
>      }
>  
> -    qdict_put_str(options, "server.host", uri->server);
> +    qdict_put_str(options, "server.host", server);
>  
> -    port_str = g_strdup_printf("%d", uri->port ?: 22);
> +    port_str = g_strdup_printf("%d", port ?: 22);
>      qdict_put_str(options, "server.port", port_str);
>  
> -    qdict_put_str(options, "path", uri->path);
> +    qdict_put_str(options, "path", path);
>  
>      /* Pick out any query parameters that we understand, and ignore
>       * the rest.
>       */
> +#ifdef HAVE_GLIB_GURI
> +    g_hash_table_iter_init(&iter, params);
> +    while (g_hash_table_iter_next(&iter, (void **)&key, (void **)&value)) {
> +#else
>      for (i = 0; i < qp->n; ++i) {
> -        if (strcmp(qp->p[i].name, "host_key_check") == 0) {
> -            qdict_put_str(options, "host_key_check", qp->p[i].value);
> +        key = qp->p[i].name;
> +        value = qp->p[i].value;
> +#endif
> +        if (g_strcmp0(key, "host_key_check") == 0) {
> +            qdict_put_str(options, "host_key_check", value);
>          }
>      }
>  
> -- 
> 2.27.0.221.ga08a83db2b

-- 
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