Function locate_in_PATH

run-command.c:191–221

* Search $PATH for a command. This emulates the path search that * execvp would perform, without actually executing the command so it * can be used before fork() to prepare to run a command using * execve() or after execvp() to diagnose why it failed. * * The caller should ensure that file contains no directory * separators. * * Returns the path to the command, as found in $PATH or NULL i

 * "foo.exe").
 */
static char *locate_in_PATH(const char *file)
{
	const char *p = getenv("PATH");
	struct strbuf buf = STRBUF_INIT;

	if (!p || !*p)
		return NULL;

	while (1) {
		const char *end = strchrnul(p, ':');

		strbuf_reset(&buf);

		/* POSIX specifies an empty entry as the current directory. */
		if (end != p) {
			strbuf_add(&buf, p, end - p);
			strbuf_addch(&buf, '/');
		}
		strbuf_addstr(&buf, file);

		if (is_executable(buf.buf))
			return strbuf_detach(&buf, NULL);

		if (!*end)
			break;
		p = end + 1;
	}

	strbuf_release(&buf);
	return NULL;
}
#endif

int exists_in_PATH(const char *command)