Merge 2c97c5d146f05ad7693fcd6d6472857ae44ae4bf into 93eef5015e0dfe8d24071dd036f9a7f02160abeb

Since they start with NUL byte, strlen() does the wrong thing.
The Lua API can already pass the real string length, so passing that on
seems the sensible thing to do.

Fixes #216

Removes SUN_LEN macro in favor of the approach used in unixstream.c
since it does not depend on strlen(), which would not work with
NUL-prefixed abstract stream socket paths.

src/unixdgram.c

@@ -16,13 +16,6 @@
 
 #define UNIXDGRAM_DATAGRAMSIZE 8192
 
-/* provide a SUN_LEN macro if sys/un.h doesn't (e.g. Android) */
-#ifndef SUN_LEN
-#define SUN_LEN(ptr) \
-  ((size_t) (((struct sockaddr_un *) 0)->sun_path)  \
-   + strlen ((ptr)->sun_path))
-#endif
-
 /*=========================================================================*\
 * Internal function prototypes
 \*=========================================================================*/
@@ -133,13 +126,12 @@ static int meth_send(lua_State *L)
 static int meth_sendto(lua_State *L)
 {
     p_unix un = (p_unix) auxiliar_checkclass(L, "unixdgram{unconnected}", 1);
-    size_t count, sent = 0;
+    size_t count, sent, len = 0;
     const char *data = luaL_checklstring(L, 2, &count);
-    const char *path = luaL_checkstring(L, 3);
+    const char *path = luaL_checklstring(L, 3, &len);
     p_timeout tm = &un->tm;
     int err;
     struct sockaddr_un remote;
-    size_t len = strlen(path);
 
     if (len >= sizeof(remote.sun_path)) {
 		lua_pushnil(L);
@@ -148,7 +140,7 @@ static int meth_sendto(lua_State *L)
 	}
 
     memset(&remote, 0, sizeof(remote));
-    strcpy(remote.sun_path, path);
+    memcpy(remote.sun_path, path, len);
     remote.sun_family = AF_UNIX;
     timeout_markstart(tm);
 #ifdef UNIX_HAS_SUN_LEN
@@ -266,15 +258,20 @@ static int meth_dirty(lua_State *L) {
 \*-------------------------------------------------------------------------*/
 static const char *unixdgram_trybind(p_unix un, const char *path, size_t len) {
     struct sockaddr_un local;
+    int err;
     if (len >= sizeof(local.sun_path)) return "path too long";
     memset(&local, 0, sizeof(local));
-    strcpy(local.sun_path, path);
+    memcpy(local.sun_path, path, len);
     local.sun_family = AF_UNIX;
-    size_t addrlen = SUN_LEN(&local);
 #ifdef UNIX_HAS_SUN_LEN
-    local.sun_len = addrlen + 1;
+    local.sun_len = sizeof(local.sun_family) + sizeof(local.sun_len)
+        + len + 1;
+    err = socket_bind(&un->sock, (SA *) &local, local.sun_len);
+
+#else
+    err = socket_bind(&un->sock, (SA *) &local,
+            sizeof(local.sun_family) + len);
 #endif
-    int err = socket_bind(&un->sock, (SA *) &local, addrlen);
     if (err != IO_DONE) socket_destroy(&un->sock);
     return socket_strerror(err);
 }
@@ -316,16 +313,20 @@ static int meth_getsockname(lua_State *L)
 static const char *unixdgram_tryconnect(p_unix un, const char *path, size_t len)
 {
     struct sockaddr_un remote;
+    int err;
     if (len >= sizeof(remote.sun_path)) return "path too long";
     memset(&remote, 0, sizeof(remote));
-    strcpy(remote.sun_path, path);
+    memcpy(remote.sun_path, path, len);
     remote.sun_family = AF_UNIX;
     timeout_markstart(&un->tm);
-    size_t addrlen = SUN_LEN(&remote);
 #ifdef UNIX_HAS_SUN_LEN
-    remote.sun_len = addrlen + 1;
+    remote.sun_len = sizeof(remote.sun_family) + sizeof(remote.sun_len)
+        + len + 1;
+    err = socket_connect(&un->sock, (SA *) &remote, remote.sun_len, &un->tm);
+#else
+    err = socket_connect(&un->sock, (SA *) &remote,
+            sizeof(remote.sun_family) + len, &un->tm);
 #endif
-    int err = socket_connect(&un->sock, (SA *) &remote, addrlen, &un->tm);
     if (err != IO_DONE) socket_destroy(&un->sock);
     return socket_strerror(err);
 }

src/unixstream.c

@@ -186,7 +186,7 @@ static const char *unixstream_trybind(p_unix un, const char *path, size_t len) {
     int err;
     if (len >= sizeof(local.sun_path)) return "path too long";
     memset(&local, 0, sizeof(local));
-    strcpy(local.sun_path, path);
+    memcpy(local.sun_path, path, len);
     local.sun_family = AF_UNIX;
 #ifdef UNIX_HAS_SUN_LEN
     local.sun_len = sizeof(local.sun_family) + sizeof(local.sun_len)
@@ -240,7 +240,7 @@ static const char *unixstream_tryconnect(p_unix un, const char *path, size_t len
     int err;
     if (len >= sizeof(remote.sun_path)) return "path too long";
     memset(&remote, 0, sizeof(remote));
-    strcpy(remote.sun_path, path);
+    memcpy(remote.sun_path, path, len);
     remote.sun_family = AF_UNIX;
     timeout_markstart(&un->tm);
 #ifdef UNIX_HAS_SUN_LEN