From 28f540f45bbacd939bfd07f213bcad2bf730b1bf Mon Sep 17 00:00:00 2001 From: Roland McGrath Date: Sat, 18 Feb 1995 01:27:10 +0000 Subject: initial import --- posix/execvp.c | 112 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 112 insertions(+) create mode 100644 posix/execvp.c (limited to 'posix/execvp.c') diff --git a/posix/execvp.c b/posix/execvp.c new file mode 100644 index 0000000000..01ae0d10a9 --- /dev/null +++ b/posix/execvp.c @@ -0,0 +1,112 @@ +/* Copyright (C) 1991, 1992 Free Software Foundation, Inc. +This file is part of the GNU C Library. + +The GNU C Library is free software; you can redistribute it and/or +modify it under the terms of the GNU Library General Public License as +published by the Free Software Foundation; either version 2 of the +License, or (at your option) any later version. + +The GNU C Library is distributed in the hope that it will be useful, +but WITHOUT ANY WARRANTY; without even the implied warranty of +MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU +Library General Public License for more details. + +You should have received a copy of the GNU Library General Public +License along with the GNU C Library; see the file COPYING.LIB. If +not, write to the Free Software Foundation, Inc., 675 Mass Ave, +Cambridge, MA 02139, USA. */ + +#include +#include +#include +#include +#include +#include +#include +#include + +#ifndef HAVE_GNU_LD +#define __environ environ +#endif + +/* Execute FILE, searching in the `PATH' environment variable if it contains + no slashes, with arguments ARGV and environment from `environ'. */ +int +DEFUN(execvp, (file, argv), CONST char *file AND char *CONST argv[]) +{ + if (strchr (file, '/') == NULL) + { + char *path, *p; + struct stat st; + size_t len; + uid_t uid; + gid_t gid; + int ngroups; + gid_t groups[NGROUPS_MAX]; + char *name; + + path = getenv ("PATH"); + if (path == NULL) + { + /* There is no `PATH' in the environment. + The default search path is the current directory + followed by the path `confstr' returns for `_CS_PATH'. */ + len = confstr (_CS_PATH, (char *) NULL, 0); + path = (char *) __alloca (1 + len); + path[0] = ':'; + (void) confstr (_CS_PATH, path + 1, len); + } + + len = strlen (file) + 1; + name = __alloca (strlen (path) + len); + uid = geteuid (); + gid = getegid (); + ngroups = getgroups (sizeof (groups) / sizeof (groups[0]), groups); + p = path; + do + { + path = p; + p = strchr (path, ':'); + if (p == NULL) + p = strchr (path, '\0'); + + if (p == path) + /* Two adjacent colons, or a colon at the beginning or the end + of `PATH' means to search the current directory. */ + (void) memcpy (name, file, len); + else + { + /* Construct the pathname to try. */ + (void) memcpy (name, path, p - path); + name[p - path] = '/'; + (void) memcpy (&name[(p - path) + 1], file, len); + } + if (stat (name, &st) == 0 && S_ISREG (st.st_mode)) + { + int bit = S_IXOTH; + if (st.st_uid == uid) + bit = S_IXUSR; + else if (st.st_gid == gid) + bit = S_IXGRP; + else + { + register int i; + for (i = 0; i < ngroups; ++i) + if (st.st_gid == groups[i]) + { + bit = S_IXGRP; + break; + } + } + if (st.st_mode & bit) + { + file = name; + break; + } + } + } + while (*p++ != '\0'); + } + + return __execve (file, argv, __environ); +} -- cgit v1.2.3