[PATCH wayland v3 1/2] Extend WAYLAND_DISPLAY and name parameter semantics to support absolute paths.

[Davide Bettio]

Extend WAYLAND_DISPLAY and name parameter semantics to
support absolute paths. For example WAYLAND_DISPLAY="/my/path/wayland-2" 
or
connect_to_socket("/my/path/wayland-2").

Signed-off-by: Davide Bettio <davide.bettio at ispirata.com>
---
  doc/man/wl_display_connect.xml |  8 ++++----
  src/wayland-client.c           | 36 
++++++++++++++++++++++++------------
  src/wayland-server.c           | 23 ++++++++++++++++++-----
  3 files changed, 46 insertions(+), 21 deletions(-)

diff --git a/doc/man/wl_display_connect.xml 
b/doc/man/wl_display_connect.xml
index 7e6e05c..b78c53f 100644
--- a/doc/man/wl_display_connect.xml
+++ b/doc/man/wl_display_connect.xml
@@ -59,10 +59,10 @@
            find it. The <varname>name</varname> argument specifies the 
name of
            the socket or <constant>NULL</constant> to use the default 
(which is
            <constant>"wayland-0"</constant>). The environment variable
-          <envar>WAYLAND_DISPLAY</envar> replaces the default value. If
-          <envar>WAYLAND_SOCKET</envar> is set, this function behaves 
like
-          <function>wl_display_connect_to_fd</function> with the 
file-descriptor
-          number taken from the environment variable.</para>
+          <envar>WAYLAND_DISPLAY</envar> replaces the default value, 
and eventually uses
+          a different path too. If <envar>WAYLAND_SOCKET</envar> is 
set, this function
+          behaves like <function>wl_display_connect_to_fd</function> 
with the
+          file-descriptor number taken from the environment 
variable.</para>

      <para><function>wl_display_connect_to_fd</function> connects to a 
Wayland
            socket with an explicit file-descriptor. The file-descriptor 
is passed
diff --git a/src/wayland-client.c b/src/wayland-client.c
index 09c594a..7c47c79 100644
--- a/src/wayland-client.c
+++ b/src/wayland-client.c
@@ -753,34 +753,46 @@ connect_to_socket(const char *name)
  	const char *runtime_dir;
  	int name_size, fd;

+	if (name == NULL)
+		name = getenv("WAYLAND_DISPLAY");
+	if (name == NULL)
+		name = "wayland-0";
+
  	runtime_dir = getenv("XDG_RUNTIME_DIR");
-	if (!runtime_dir) {
-		wl_log("error: XDG_RUNTIME_DIR not set in the environment.\n");
+	if (!runtime_dir && (name[0] != '/')) {
+		wl_log("error: WAYLAND_DISPLAY either not set to an absolute path or 
XDG_RUNTIME_DIR not set in the environment.\n");
  		/* to prevent programs reporting
  		 * "failed to create display: Success" */
  		errno = ENOENT;
  		return -1;
  	}

-	if (name == NULL)
-		name = getenv("WAYLAND_DISPLAY");
-	if (name == NULL)
-		name = "wayland-0";
-
  	fd = wl_os_socket_cloexec(PF_LOCAL, SOCK_STREAM, 0);
  	if (fd < 0)
  		return -1;

  	memset(&addr, 0, sizeof addr);
  	addr.sun_family = AF_LOCAL;
-	name_size =
-		snprintf(addr.sun_path, sizeof addr.sun_path,
-			 "%s/%s", runtime_dir, name) + 1;
+	if (name[0] != '/') {
+		name_size =
+			snprintf(addr.sun_path, sizeof addr.sun_path,
+				 "%s/%s", runtime_dir, name) + 1;
+	} else {
+		/* absolute path */
+		name_size =
+			snprintf(addr.sun_path, sizeof addr.sun_path,
+				 "%s", name) + 1;
+	}

  	assert(name_size > 0);
  	if (name_size > (int)sizeof addr.sun_path) {
-		wl_log("error: socket path \"%s/%s\" plus null terminator"
-		       " exceeds 108 bytes\n", runtime_dir, name);
+		if (name[0] != '/') {
+			wl_log("error: socket path \"%s/%s\" plus null terminator"
+			       " exceeds %i bytes\n", runtime_dir, name, (int) 
sizeof(addr.sun_path));
+		} else {
+			wl_log("error: socket path \"%s\" plus null terminator"
+			       " exceeds %i bytes\n", name, (int) sizeof(addr.sun_path));
+		}
  		close(fd);
  		/* to prevent programs reporting
  		 * "failed to add socket: Success" */
diff --git a/src/wayland-server.c b/src/wayland-server.c
index 0f04f66..fa2ad85 100644
--- a/src/wayland-server.c
+++ b/src/wayland-server.c
@@ -1109,15 +1109,28 @@ wl_socket_init_for_display_name(struct wl_socket 
*s, const char *name)
  	}

  	s->addr.sun_family = AF_LOCAL;
-	name_size = snprintf(s->addr.sun_path, sizeof s->addr.sun_path,
-			     "%s/%s", runtime_dir, name) + 1;
+	if (name[0] != '/') {
+		name_size = snprintf(s->addr.sun_path, sizeof s->addr.sun_path,
+				     "%s/%s", runtime_dir, name) + 1;

-	s->display_name = (s->addr.sun_path + name_size - 1) - strlen(name);
+		s->display_name = (s->addr.sun_path + name_size - 1) - strlen(name);
+	} else {
+		/* absolute path */
+		name_size = snprintf(s->addr.sun_path, sizeof s->addr.sun_path,
+				     "%s", name) + 1;
+
+		s->display_name = strrchr(s->addr.sun_path, '/') + 1;
+	}

  	assert(name_size > 0);
  	if (name_size > (int)sizeof s->addr.sun_path) {
-		wl_log("error: socket path \"%s/%s\" plus null terminator"
-		       " exceeds 108 bytes\n", runtime_dir, name);
+		if (name[0] != '/') {
+			wl_log("error: socket path \"%s/%s\" plus null terminator"
+                               " exceeds %i bytes\n", runtime_dir, 
name, (int) sizeof(s->addr.sun_path));
+		} else {
+			wl_log("error: socket path \"%s\" plus null terminator"
+			       " exceeds %i bytes\n", name, (int) sizeof(s->addr.sun_path));
+		}
  		*s->addr.sun_path = 0;
  		/* to prevent programs reporting
  		 * "failed to add socket: Success" */
-- 
2.1.0