git/shell.c
Michal Ostrowski 77cb17e940 Exec git programs without using PATH.
The git suite may not be in PATH (and thus programs such as
git-send-pack could not exec git-rev-list).  Thus there is a need for
logic that will locate these programs.  Modifying PATH is not
desirable as it result in behavior differing from the user's
intentions, as we may end up prepending "/usr/bin" to PATH.

- git C programs will use exec*_git_cmd() APIs to exec sub-commands.
- exec*_git_cmd() will execute a git program by searching for it in
  the following directories:
	1. --exec-path (as used by "git")
	2. The GIT_EXEC_PATH environment variable.
	3. $(gitexecdir) as set in Makefile (default value $(bindir)).
- git wrapper will modify PATH as before to enable shell scripts to
  invoke "git-foo" commands.

Ideally, shell scripts should use the git wrapper to become independent
of PATH, and then modifying PATH will not be necessary.

[jc: with minor updates after a brief review.]

Signed-off-by: Michal Ostrowski <mostrows@watson.ibm.com>
Signed-off-by: Junio C Hamano <junkio@cox.net>
2006-01-13 16:49:01 -08:00

62 lines
1.2 KiB
C

#include "cache.h"
#include "quote.h"
#include "exec_cmd.h"
static int do_generic_cmd(const char *me, char *arg)
{
const char *my_argv[4];
if (!arg || !(arg = sq_dequote(arg)))
die("bad argument");
if (strncmp(me, "git-", 4))
die("bad command");
my_argv[0] = me + 4;
my_argv[1] = arg;
my_argv[2] = NULL;
return execv_git_cmd((char**) my_argv);
}
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 },
{ NULL },
};
int main(int argc, char **argv)
{
char *prog;
struct commands *cmd;
/* We want to see "-c cmd args", and nothing else */
if (argc != 3 || strcmp(argv[1], "-c"))
die("What do you think I am? A shell?");
prog = argv[2];
argv += 2;
argc -= 2;
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));
}
die("unrecognized command '%s'", prog);
}