arid.cpp

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