Andrew's git - gitweb.git/blob - builtin/get-tar-commit-id.c

   1/*
   2 * Copyright (c) 2005, 2006 Rene Scharfe
   3 */
   4#include "cache.h"
   5#include "commit.h"
   6#include "tar.h"
   7#include "builtin.h"
   8#include "quote.h"
   9
  10static const char builtin_get_tar_commit_id_usage[] =
  11"git get-tar-commit-id";
  12
  13/* ustar header + extended global header content */
  14#define RECORDSIZE      (512)
  15#define HEADERSIZE (2 * RECORDSIZE)
  16
  17int cmd_get_tar_commit_id(int argc, const char **argv, const char *prefix)
  18{
  19        char buffer[HEADERSIZE];
  20        struct ustar_header *header = (struct ustar_header *)buffer;
  21        char *content = buffer + RECORDSIZE;
  22        const char *comment;
  23        ssize_t n;
  24
  25        if (argc != 1)
  26                usage(builtin_get_tar_commit_id_usage);
  27
  28        n = read_in_full(0, buffer, HEADERSIZE);
  29        if (n < 0)
  30                die_errno("git get-tar-commit-id: read error");
  31        if (n != HEADERSIZE)
  32                die_errno("git get-tar-commit-id: EOF before reading tar header");
  33        if (header->typeflag[0] != 'g')
  34                return 1;
  35        if (!skip_prefix(content, "52 comment=", &comment))
  36                return 1;
  37
  38        if (write_in_full(1, comment, 41) < 0)
  39                die_errno("git get-tar-commit-id: write error");
  40
  41        return 0;
  42}