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#include "cache.h"
#include "quote.h"
#include "exec_cmd.h"
#include "strbuf.h"
#define COMMAND_DIR "git-shell-commands"
static int do_generic_cmd(const char *me, char *arg)
{
const char *my_argv[4];
setup_path();
if (!arg || !(arg = sq_dequote(arg)))
die("bad argument");
if (prefixcmp(me, "git-"))
die("bad command");
my_argv[0] = me + 4;
my_argv[1] = arg;
my_argv[2] = NULL;
return execv_git_cmd(my_argv);
}
static int do_cvs_cmd(const char *me, char *arg)
{
const char *cvsserver_argv[3] = {
"cvsserver", "server", NULL
};
if (!arg || strcmp(arg, "server"))
die("git-cvsserver only handles server: %s", arg);
setup_path();
return execv_git_cmd(cvsserver_argv);
}
static int is_valid_cmd_name(const char *cmd)
{
/* Test command contains no . or / characters */
return cmd[strcspn(cmd, "./")] == '\0';
}
static char *make_cmd(const char *prog)
{
char *prefix = xmalloc((strlen(prog) + strlen(COMMAND_DIR) + 2));
strcpy(prefix, COMMAND_DIR);
strcat(prefix, "/");
strcat(prefix, prog);
return prefix;
}
static void cd_to_homedir(void)
{
const char *home = getenv("HOME");
if (!home)
die("could not determine user's home directory; HOME is unset");
if (chdir(home) == -1)
die("could not chdir to user's home directory");
}
static struct commands {
const char *name;
int (*exec)(const char *me, char *arg);
} cmd_list[] = {
{ "git-receive-pack", do_generic_cmd },
{ "git-upload-pack", do_generic_cmd },
{ "git-upload-archive", do_generic_cmd },
{ "cvs", do_cvs_cmd },
{ NULL },
};
int main(int argc, char **argv)
{
char *prog;
const char **user_argv;
struct commands *cmd;
int devnull_fd;
/*
* Always open file descriptors 0/1/2 to avoid clobbering files
* in die(). It also avoids not messing up when the pipes are
* dup'ed onto stdin/stdout/stderr in the child processes we spawn.
*/
devnull_fd = open("/dev/null", O_RDWR);
while (devnull_fd >= 0 && devnull_fd <= 2)
devnull_fd = dup(devnull_fd);
if (devnull_fd == -1)
die_errno("opening /dev/null failed");
close (devnull_fd);
/*
* Special hack to pretend to be a CVS server
*/
if (argc == 2 && !strcmp(argv[1], "cvs server"))
argv--;
/*
* We do not accept anything but "-c" followed by "cmd arg",
* where "cmd" is a very limited subset of git commands.
*/
else if (argc != 3 || strcmp(argv[1], "-c"))
die("What do you think I am? A shell?");
prog = xstrdup(argv[2]);
if (!strncmp(prog, "git", 3) && isspace(prog[3]))
/* Accept "git foo" as if the caller said "git-foo". */
prog[3] = '-';
for (cmd = cmd_list ; cmd->name ; cmd++) {
int len = strlen(cmd->name);
char *arg;
if (strncmp(cmd->name, prog, len))
continue;
arg = NULL;
switch (prog[len]) {
case '\0':
arg = NULL;
break;
case ' ':
arg = prog + len + 1;
break;
default:
continue;
}
exit(cmd->exec(cmd->name, arg));
}
cd_to_homedir();
if (split_cmdline(prog, &user_argv) != -1) {
if (is_valid_cmd_name(user_argv[0])) {
prog = make_cmd(user_argv[0]);
user_argv[0] = prog;
execv(user_argv[0], (char *const *) user_argv);
}
free(prog);
free(user_argv);
die("unrecognized command '%s'", argv[2]);
} else {
free(prog);
die("invalid command format '%s'", argv[2]);
}
}
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