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#include "rsh.h"
#include <string.h>
#include <sys/types.h>
#include <sys/socket.h>
#include "cache.h"
#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;
if ( quote ) {
oc = shell_quote(p, size, str);
} else {
oc = strlen(str);
memcpy(p, str, (oc >= size) ? size-1 : oc);
}
if ( oc >= size ) {
p[size-1] = '\0';
*ptrp += size-1;
*sizep = 1;
return 1; /* Overflow, string unusable */
}
*ptrp += oc;
*sizep -= oc;
return 0;
}
int setup_connection(int *fd_in, int *fd_out, const char *remote_prog,
char *url, int rmt_argc, char **rmt_argv)
{
char *host;
char *path;
int sv[2];
char command[COMMAND_SIZE];
char *posn;
int sizen;
int of;
int i;
if (!strcmp(url, "-")) {
*fd_in = 0;
*fd_out = 1;
return 0;
}
host = strstr(url, "//");
if (host) {
host += 2;
path = strchr(host, '/');
} else {
host = url;
path = strchr(host, ':');
if (path)
*(path++) = '\0';
}
if (!path) {
return error("Bad URL: %s", url);
}
/* $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);
}
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_basename, host, command, NULL);
}
close(sv[0]);
*fd_in = sv[1];
*fd_out = sv[1];
return 0;
}
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