arid.cpp

   1 #include <iostream>
   2 #include <string.h>
   3 #include "minimal/mapping.h"
   4
   5 struct ar_hdr {
   6     char ar_name[16];
   7     char ar_date[12];
   8     char ar_uid[6];
   9     char ar_gid[6];
  10     char ar_mode[8];
  11     char ar_size[10];
  12 #define ARFMAG "`\n"
  13     char ar_fmag[2];
  14 };
  15
  16 int main(int argc, char *argv[]) {
  17     size_t size;
  18     _assert(argc == 2);
  19     uint8_t *data = reinterpret_cast<uint8_t *>(map(argv[1], 0, _not(size_t), &size, false));
  20     data += 8;
  21     uint8_t *end = data + size;
  22     while (end - data >= sizeof(struct ar_hdr)) {
  23         struct ar_hdr *head = reinterpret_cast<struct ar_hdr *>(data);
  24         memset(head->ar_date + 1, ' ', sizeof(head->ar_date) - 1);
  25         head->ar_date[0] = '0';
  26         size_t length = strtoul(head->ar_size, NULL, 10);
  27         data += length + sizeof(struct ar_hdr);
  28     }
  29     return 0;
  30 }