LXR toybox/toys/pending/dumpleases.c

   1/* dumpleases.c - Dump the leases granted by udhcpd.
   2 *
   3 * Copyright 2013 Sandeep Sharma <sandeep.jack2756@gmail.com>
   4 * Copyright 2013 Kyungwan Han <asura321@gmail.com>
   5 *
   6
   7USE_DUMPLEASES(NEWTOY(dumpleases, ">0arf:[!ar]", TOYFLAG_USR|TOYFLAG_BIN))
   8
   9config DUMPLEASES
  10  bool "dumpleases"
  11  default n
  12  help
  13    usage: dumpleases [-r|-a] [-f LEASEFILE]
  14
  15    Display DHCP leases granted by udhcpd
  16    -f FILE,  Lease file
  17    -r        Show remaining time
  18    -a        Show expiration time
  19*/
  20
  21#define FOR_dumpleases
  22#include "toys.h"
  23
  24GLOBALS(
  25    char *file;
  26)
  27
  28//lease structure
  29struct lease { 
  30  uint32_t expires;
  31  uint32_t lease_nip;
  32  uint8_t lease_mac[6];
  33  char hostname[20];
  34  uint8_t pad[2]; //Padding
  35};
  36
  37void dumpleases_main(void)
  38{
  39  struct in_addr addr;
  40  struct lease lease_struct;
  41  int64_t written_time , current_time, exp;
  42  int i, fd; 
  43  
  44  if(!(toys.optflags & FLAG_f)) TT.file = "/var/lib/misc/dhcpd.leases"; //DEF_LEASE_FILE
  45  fd = xopenro(TT.file);
  46  xprintf("Mac Address       IP Address      Host Name           Expires %s\n", (toys.optflags & FLAG_a) ? "at" : "in");
  47  xread(fd, &written_time, sizeof(written_time));
  48  current_time = time(NULL);
  49  written_time = SWAP_BE64(written_time);
  50  if(current_time < written_time) written_time = current_time;
  51
  52  while(sizeof(lease_struct) == 
  53      (readall(fd, &lease_struct, sizeof(lease_struct)))) {
  54    for (i = 0; i < 6; i++) printf(":%02x"+ !i, lease_struct.lease_mac[i]);
  55    
  56    addr.s_addr = lease_struct.lease_nip;
  57    lease_struct.hostname[19] = '\0';
  58    xprintf(" %-16s%-20s", inet_ntoa(addr), lease_struct.hostname );
  59    exp = ntohl(lease_struct.expires) + written_time;
  60    if (exp <= current_time) {
  61      xputs("expired");
  62      continue;
  63    }
  64    if (!(toys.optflags & FLAG_a)) { 
  65      unsigned dt, hr, m;
  66      unsigned expires = exp - current_time;
  67      dt = expires / (24*60*60); expires %= (24*60*60);
  68      hr = expires / (60*60); expires %= (60*60);
  69      m = expires / 60; expires %= 60;
  70      if (dt) xprintf("%u days ", dt);
  71      xprintf("%02u:%02u:%02u\n", hr, m, (unsigned)expires);
  72    } else {
  73      fputs(ctime((const time_t*)&exp), stdout);
  74    }
  75  }
  76  xclose(fd);
  77}
  78