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
  10 //config:config LSOF
  11 //config:       bool "lsof"
  12 //config:       default y
  13 //config:       help
  14 //config:         Show open files in the format of:
  15 //config:         PID <TAB> /path/to/executable <TAB> /path/to/opened/file
  16
  17 //applet:IF_LSOF(APPLET(lsof, BB_DIR_USR_BIN, BB_SUID_DROP))
  18
  19 //kbuild:lib-$(CONFIG_LSOF) += lsof.o
  20
  21 //usage:#define lsof_trivial_usage
  22 //usage:       ""
  23 //usage:#define lsof_full_usage "\n\n"
  24 //usage:       "Show all open files"
  25
  26 #include "libbb.h"
  27
  28 /*
  29  * Examples of "standard" lsof output:
  30  *
  31  * COMMAND    PID USER   FD   TYPE             DEVICE     SIZE       NODE NAME
  32  * init         1 root  cwd    DIR                8,5     4096          2 /
  33  * init         1 root  rtd    DIR                8,5     4096          2 /
  34  * init         1 root  txt    REG                8,5   872400      63408 /app/busybox-1.19.2/busybox
  35  * rpc.portm 1064 root  mem    REG                8,5    43494      47451 /app/glibc-2.11/lib/libnss_files-2.11.so
  36  * rpc.portm 1064 root    3u  IPv4               2178                 UDP *:111
  37  * rpc.portm 1064 root    4u  IPv4               1244                 TCP *:111 (LISTEN)
  38  * runsvdir  1116 root    0r   CHR                1,3                1214 /dev/null
  39  * runsvdir  1116 root    1w   CHR                1,3                1214 /dev/null
  40  * runsvdir  1116 root    2w   CHR                1,3                1214 /dev/null
  41  * runsvdir  1116 root    3r   DIR                8,6     1560      58359 /.local/var/service
  42  * gpm       1128 root    4u  unix 0xffff88007c09ccc0                1302 /dev/gpmctl
  43  */
  44
  45 int lsof_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
  46 int lsof_main(int argc UNUSED_PARAM, char **argv UNUSED_PARAM)
  47 {
  48         procps_status_t *proc = NULL;
  49
  50         while ((proc = procps_scan(proc, PSSCAN_PID|PSSCAN_EXE)) != NULL) {
  51                 char name[sizeof("/proc/%u/fd/0123456789") + sizeof(int)*3];
  52                 unsigned baseofs;
  53                 DIR *d_fd;
  54                 char *fdlink;
  55                 struct dirent *entry;
  56
  57                 if (getpid() == proc->pid)
  58                         continue;
  59
  60                 baseofs = sprintf(name, "/proc/%u/fd/", proc->pid);
  61                 d_fd = opendir(name);
  62                 if (d_fd) {
  63                         while ((entry = readdir(d_fd)) != NULL) {
  64                                 /* Skip entries '.' and '..' (and any hidden file) */
  65                                 if (entry->d_name[0] == '.')
  66                                         continue;
  67
  68                                 safe_strncpy(name + baseofs, entry->d_name, 10);
  69                                 if ((fdlink = xmalloc_readlink(name)) != NULL) {
  70                                         printf("%d\t%s\t%s\n", proc->pid, proc->exe, fdlink);
  71                                         free(fdlink);
  72                                 }
  73                         }
  74                         closedir(d_fd);
  75                 }
  76         }
  77
  78         return EXIT_SUCCESS;
  79 }