LXR busybox/procps/pwdx.c

   1/* vi: set sw=4 ts=4: */
   2/*
   3 * pwdx implementation for busybox
   4 *
   5 * Copyright (c) 2004 Nicholas Miell
   6 * ported from procps by Pere Orga <gotrunks@gmail.com> 2011
   7 *
   8 * Licensed under GPLv2, see file LICENSE in this source tree.
   9 */
  10//config:config PWDX
  11//config:       bool "pwdx (3.7 kb)"
  12//config:       default y
  13//config:       help
  14//config:       Report current working directory of a process
  15
  16//applet:IF_PWDX(APPLET_NOFORK(pwdx, pwdx, BB_DIR_USR_BIN, BB_SUID_DROP, pwdx))
  17
  18//kbuild:lib-$(CONFIG_PWDX) += pwdx.o
  19
  20//usage:#define pwdx_trivial_usage
  21//usage:       "PID..."
  22//usage:#define pwdx_full_usage "\n\n"
  23//usage:       "Show current directory for PIDs"
  24
  25#include "libbb.h"
  26
  27int pwdx_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
  28int pwdx_main(int argc UNUSED_PARAM, char **argv)
  29{
  30        getopt32(argv, "^" "" "\0" "-1");
  31        argv += optind;
  32
  33        do {
  34                char buf[sizeof("/proc/%u/cwd") + sizeof(int)*3];
  35                unsigned pid;
  36                char *s;
  37                char *arg = *argv;
  38
  39                // Allowed on the command line:
  40                // /proc/NUM
  41                // NUM
  42                if (is_prefixed_with(arg, "/proc/"))
  43                        arg += 6;
  44
  45                pid = bb_strtou(arg, NULL, 10);
  46                if (errno)
  47                        bb_error_msg_and_die("invalid process id: '%s'", arg);
  48
  49                sprintf(buf, "/proc/%u/cwd", pid);
  50
  51                /* NOFORK: only one alloc is allowed; must free */
  52                s = xmalloc_readlink(buf);
  53                // "pwdx /proc/1" says "/proc/1: DIR", not "1: DIR"
  54                printf("%s: %s\n", *argv, s ? s : strerror(errno == ENOENT ? ESRCH : errno));
  55                free(s);
  56        } while (*++argv);
  57
  58        return EXIT_SUCCESS;
  59}
  60