procps/lsof.c

   1 /* vi: set sw=4 ts=4: */
   2 /*
   3  * Mini lsof implementation for busybox
   4  *
   5  * Copyright (C) 2012 by Sven Oliver 'SvOlli' Moll <svolli@svolli.de>
   6  *
   7  * Licensed under GPLv2, see file LICENSE in this source tree.
   8  */
   9 //config:config LSOF
  10 //config:       bool "lsof (3.6 kb)"
  11 //config:       default y
  12 //config:       help
  13 //config:       Show open files in the format of:
  14 //config:       PID <TAB> /path/to/executable <TAB> /path/to/opened/file
  15
  16 //applet:IF_LSOF(APPLET(lsof, BB_DIR_USR_BIN, BB_SUID_DROP))
  17
  18 //kbuild:lib-$(CONFIG_LSOF) += lsof.o
  19
  20 //usage:#define lsof_trivial_usage
  21 //usage:       ""
  22 //usage:#define lsof_full_usage "\n\n"
  23 //usage:       "Show all open files"
  24
  25 #include "libbb.h"
  26
  27 /*
  28  * Examples of "standard" lsof output:
  29  *
  30  * COMMAND    PID USER   FD   TYPE             DEVICE     SIZE       NODE NAME
  31  * init         1 root  cwd    DIR                8,5     4096          2 /
  32  * init         1 root  rtd    DIR                8,5     4096          2 /
  33  * init         1 root  txt    REG                8,5   872400      63408 /app/busybox-1.19.2/busybox
  34  * rpc.portm 1064 root  mem    REG                8,5    43494      47451 /app/glibc-2.11/lib/libnss_files-2.11.so
  35  * rpc.portm 1064 root    3u  IPv4               2178                 UDP *:111
  36  * rpc.portm 1064 root    4u  IPv4               1244                 TCP *:111 (LISTEN)
  37  * runsvdir  1116 root    0r   CHR                1,3                1214 /dev/null
  38  * runsvdir  1116 root    1w   CHR                1,3                1214 /dev/null
  39  * runsvdir  1116 root    2w   CHR                1,3                1214 /dev/null
  40  * runsvdir  1116 root    3r   DIR                8,6     1560      58359 /.local/var/service
  41  * gpm       1128 root    4u  unix 0xffff88007c09ccc0                1302 /dev/gpmctl
  42  */
  43
  44 int lsof_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
  45 int lsof_main(int argc UNUSED_PARAM, char **argv UNUSED_PARAM)
  46 {
  47         procps_status_t *proc = NULL;
  48
  49         while ((proc = procps_scan(proc, PSSCAN_PID|PSSCAN_EXE)) != NULL) {
  50                 char name[sizeof("/proc/%u/fd/0123456789") + sizeof(int)*3];
  51                 unsigned baseofs;
  52                 DIR *d_fd;
  53                 char *fdlink;
  54                 struct dirent *entry;
  55
  56                 if (getpid() == proc->pid)
  57                         continue;
  58
  59                 baseofs = sprintf(name, "/proc/%u/fd/", proc->pid);
  60                 d_fd = opendir(name);
  61                 if (d_fd) {
  62                         while ((entry = readdir(d_fd)) != NULL) {
  63                                 /* Skip entries '.' and '..' (and any hidden file) */
  64                                 if (entry->d_name[0] == '.')
  65                                         continue;
  66
  67                                 safe_strncpy(name + baseofs, entry->d_name, 10);
  68                                 if ((fdlink = xmalloc_readlink(name)) != NULL) {
  69                                         printf("%d\t%s\t%s\n", proc->pid, proc->exe, fdlink);
  70                                         free(fdlink);
  71                                 }
  72                         }
  73                         closedir(d_fd);
  74                 }
  75         }
  76
  77         return EXIT_SUCCESS;
  78 }