#define COMMAND_SIZE 4096
+/*
+ * 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)
{
int sv[2];
char command[COMMAND_SIZE];
char *posn;
+ int sizen;
+ int of;
int i;
if (!strcmp(url, "-")) {
if (!path) {
return error("Bad URL: %s", url);
}
- /* ssh <host> 'cd <path>; stdio-pull <arg...> <commit-id>' */
- snprintf(command, COMMAND_SIZE,
- "%s='%s' %s",
- GIT_DIR_ENVIRONMENT, path, remote_prog);
- *path = '\0';
- 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];