Make sure get_sha1 does not accept ambiguous sha1 prefix (again).

diff --git a/rsh.c b/rsh.c
index 3eb9d9160531de91cbccfc1fdea2e9007a9cbfec..bad5cff2c287d3c7dd288308428b89e0cb12299d 100644 (file)
--- a/rsh.c
+++ b/rsh.c
@@ -8,7 +8,72 @@
 
 #define COMMAND_SIZE 4096
 
-int setup_connection(int *fd_in, int *fd_out, char *remote_prog, 
+/*
+ * Write a shell-quoted version of a string into a buffer, and
+ * return bytes that ought to be output excluding final null.
+ */
+static int shell_quote(char *buf, int nmax, const char *str)
+{
+       char ch;
+       int nq;
+       int oc = 0;
+
+       while ( (ch = *str++) ) {
+               nq = 0;
+               if ( strchr(" !\"#$%&\'()*;<=>?[\\]^`{|}", ch) )
+                       nq = 1;
+
+               if ( nq ) {
+                       if ( nmax > 1 ) {
+                               *buf++ = '\\';
+                               nmax--;
+                       }
+                       oc++;
+               }
+
+               if ( nmax > 1 ) {
+                       *buf++ = ch;
+                       nmax--;
+               }
+               oc++;
+       }
+
+       if ( nmax )
+               *buf = '\0';
+
+       return oc;
+}
+                       
+/*
+ * Append a string to a string buffer, with or without quoting.  Return true
+ * if the buffer overflowed.
+ */
+static int add_to_string(char **ptrp, int *sizep, const char *str, int quote)
+{
+       char *p = *ptrp;
+       int size = *sizep;
+       int oc;
+       int err = 0;
+
+       if ( quote ) {
+               oc = shell_quote(p, size, str);
+       } else {
+               oc = strlen(str);
+               memcpy(p, str, (oc >= size) ? size-1 : oc);
+       }
+
+       if ( oc >= size ) {
+               err = 1;
+               oc = size-1;
+       }
+
+       *ptrp  += oc;
+       **ptrp  = '\0';
+       *sizep -= oc;
+       return err;
+}
+
+int setup_connection(int *fd_in, int *fd_out, const char *remote_prog, 
                     char *url, int rmt_argc, char **rmt_argv)
 {
        char *host;
@@ -16,6 +81,8 @@ int setup_connection(int *fd_in, int *fd_out, char *remote_prog,
        int sv[2];
        char command[COMMAND_SIZE];
        char *posn;
+       int sizen;
+       int of;
        int i;
 
        if (!strcmp(url, "-")) {
@@ -25,37 +92,55 @@ int setup_connection(int *fd_in, int *fd_out, char *remote_prog,
        }
 
        host = strstr(url, "//");
-       if (!host) {
-               return error("Bad URL: %s", url);
+       if (host) {
+               host += 2;
+               path = strchr(host, '/');
+       } else {
+               host = url;
+               path = strchr(host, ':');
+               if (path)
+                       *(path++) = '\0';
        }
-       host += 2;
-       path = strchr(host, '/');
        if (!path) {
                return error("Bad URL: %s", url);
        }
-       *(path++) = '\0';
-       /* ssh <host> 'cd /<path>; stdio-pull <arg...> <commit-id>' */
-       snprintf(command, COMMAND_SIZE, 
-                "%s='/%s' %s",
-                GIT_DIR_ENVIRONMENT, path, remote_prog);
-       posn = command + strlen(command);
-       for (i = 0; i < rmt_argc; i++) {
-               *(posn++) = ' ';
-               strncpy(posn, rmt_argv[i], COMMAND_SIZE - (posn - command));
-               posn += strlen(rmt_argv[i]);
-               if (posn - command + 4 >= COMMAND_SIZE) {
-                       return error("Command line too long");
-               }
+       /* $GIT_RSH <host> "env GIR_DIR=<path> <remote_prog> <args...>" */
+       sizen = COMMAND_SIZE;
+       posn = command;
+       of = 0;
+       of |= add_to_string(&posn, &sizen, "env ", 0);
+       of |= add_to_string(&posn, &sizen, GIT_DIR_ENVIRONMENT, 0);
+       of |= add_to_string(&posn, &sizen, "=", 0);
+       of |= add_to_string(&posn, &sizen, path, 1);
+       of |= add_to_string(&posn, &sizen, " ", 0);
+       of |= add_to_string(&posn, &sizen, remote_prog, 1);
+
+       for ( i = 0 ; i < rmt_argc ; i++ ) {
+               of |= add_to_string(&posn, &sizen, " ", 0);
+               of |= add_to_string(&posn, &sizen, rmt_argv[i], 1);
        }
-       strcpy(posn, " -");
-       if (socketpair(AF_UNIX, SOCK_STREAM, 0, sv)) {
+
+       of |= add_to_string(&posn, &sizen, " -", 0);
+
+       if ( of )
+               return error("Command line too long");
+
+       if (socketpair(AF_UNIX, SOCK_STREAM, 0, sv))
                return error("Couldn't create socket");
-       }
+
        if (!fork()) {
+               const char *ssh, *ssh_basename;
+               ssh = getenv("GIT_SSH");
+               if (!ssh) ssh = "ssh";
+               ssh_basename = strrchr(ssh, '/');
+               if (!ssh_basename)
+                       ssh_basename = ssh;
+               else
+                       ssh_basename++;
                close(sv[1]);
                dup2(sv[0], 0);
                dup2(sv[0], 1);
-               execlp("ssh", "ssh", host, command, NULL);
+               execlp(ssh, ssh_basename, host, command, NULL);
        }
        close(sv[0]);
        *fd_in = sv[1];