talk_to_socket: split arguments in packet with \0

In the packet that is written to the daemon via talk_to_socket(), we were
previously using a space to separate each argument, and asking uzbl to quote
the arguments as though for the shell. This just makes life complicated since
we have to undo this in the daemon.

This commit changes the behaviour so that arguments are delimited by ASCII
nul (\0) in the packet. The daemon can thus unambiguously determine where
each argument ends and the next begins.

diff --git a/uzbl.c b/uzbl.c
index 77d76e9..fb83666 100644 (file)
--- a/uzbl.c
+++ b/uzbl.c
@@ -55,6 +55,7 @@
 #include <fcntl.h>
 #include <signal.h>
 #include <poll.h>
+#include <sys/uio.h>
 #include <sys/ioctl.h>
 #include "uzbl.h"
 #include "config.h"
@@ -810,7 +811,7 @@ struct {char *key; CommandInfo value;} cmdlist[] =
     { "sync_spawn",         {spawn_sync, 0}                }, // needed for cookie handler
     { "sh",                 {spawn_sh, 0}                  },
     { "sync_sh",            {spawn_sh_sync, 0}             }, // needed for cookie handler
-    { "talk_to_socket",     {talk_to_socket, TRUE}         },
+    { "talk_to_socket",     {talk_to_socket, 0}            },
     { "exit",               {close_uzbl, 0}                },
     { "search",             {search_forward_text, TRUE}    },
     { "search_reverse",     {search_reverse_text, TRUE}    },
@@ -1402,9 +1403,11 @@ talk_to_socket(WebKitWebView *web_view, GArray *argv, GString *result) {
 
     int fd, len;
     struct sockaddr_un sa;
-    char* sockpath, * cmd;
-    ssize_t cmd_len, ret;
+    char* sockpath;
+    ssize_t ret;
     struct pollfd pfd;
+    struct iovec* iov;
+    guint i;
 
     if(uzbl.comm.sync_stdout) uzbl.comm.sync_stdout = strfree(uzbl.comm.sync_stdout);
 
@@ -1413,31 +1416,20 @@ talk_to_socket(WebKitWebView *web_view, GArray *argv, GString *result) {
        re-opening for every call. Also we could launch a script if socket connect
        fails. */
 
-    /* Test arguments passed in correctly: argv should be an array of one element,
-       which should be a string consisting of the socket path followed by a space
-       followed by the command to write to the socket. Check that the socket path
-       is valid (starts with '/' and fits in a sockaddr_un.sun_path[]). */
-    if(argv->len != 1) {
-        g_printerr("talk_to_socket called with argv->len %d\n", (int)(argv->len));
-        return;
-    }
-
-    sockpath = g_array_index(argv, char*, 0);
-    cmd = strchr(sockpath, ' ');
-    if(!cmd || *sockpath != '/' || (cmd - sockpath) >= (int)sizeof(sa.sun_path)) {
-        g_printerr("talk_to_socket called incorrectly (%s)\n", sockpath);
+    /* First element argv[0] is path to socket. Following elements are tokens to
+       write to the socket. We write them as a single packet with each token
+       separated by an ASCII nul (\0). */
+    if(argv->len < 2) {
+        g_printerr("talk_to_socket called with only %d args (need at least two).\n",
+            (int)argv->len);
         return;
     }
 
     /* copy socket path, null terminate result */
-    memcpy(sa.sun_path, sockpath, (cmd - sockpath));
-    sa.sun_path[cmd - sockpath] = 0;
+    sockpath = g_array_index(argv, char*, 0);
+    g_strlcpy(sa.sun_path, sockpath, sizeof(sa.sun_path));
     sa.sun_family = AF_UNIX;
 
-    /* point to start of command, find its length in bytes */
-    ++cmd;
-    cmd_len = strlen(cmd);
-
     /* create socket file descriptor and connect it to path */
     fd = socket(AF_UNIX, SOCK_SEQPACKET, 0);
     if(fd == -1) {
@@ -1450,8 +1442,21 @@ talk_to_socket(WebKitWebView *web_view, GArray *argv, GString *result) {
         return;
     }
 
+    /* build request vector */
+    iov = g_malloc(sizeof(struct iovec) * (argv->len - 1));
+    if(!iov) {
+        g_printerr("talk_to_socket: unable to allocated memory for token vector\n");
+        close(fd);
+        return;
+    }
+    for(i = 1; i < argv->len; ++i) {
+        iov[i - 1].iov_base = g_array_index(argv, char*, i);
+        iov[i - 1].iov_len = strlen(iov[i - 1].iov_base) + 1; /* string plus \0 */
+    }
+
     /* write request */
-    ret = write(fd, cmd, cmd_len);
+    ret = writev(fd, iov, argv->len - 1);
+    g_free(iov);
     if(ret == -1) {
         g_printerr("talk_to_socket: write failed (%s)\n", strerror(errno));
         close(fd);