root/builtin/get-tar-commit-id.c

DEFINITIONS

1. cmd_get_tar_commit_id

/*
 * Copyright (c) 2005, 2006 Rene Scharfe
 */
#include "cache.h"
#include "commit.h"
#include "tar.h"
#include "builtin.h"
#include "quote.h"

static const char builtin_get_tar_commit_id_usage[] =
"git get-tar-commit-id";

/* ustar header + extended global header content */
#define RECORDSIZE      (512)
#define HEADERSIZE (2 * RECORDSIZE)

int cmd_get_tar_commit_id(int argc, const char **argv, const char *prefix)
{
        char buffer[HEADERSIZE];
        struct ustar_header *header = (struct ustar_header *)buffer;
        char *content = buffer + RECORDSIZE;
        const char *comment;
        ssize_t n;

        if (argc != 1)
                usage(builtin_get_tar_commit_id_usage);

        n = read_in_full(0, buffer, HEADERSIZE);
        if (n < HEADERSIZE)
                die("git get-tar-commit-id: read error");
        if (header->typeflag[0] != 'g')
                return 1;
        if (!skip_prefix(content, "52 comment=", &comment))
                return 1;

        n = write_in_full(1, comment, 41);
        if (n < 41)
                die_errno("git get-tar-commit-id: write error");

        return 0;
}