Andrew's git - gitweb.git/blob

   1/*
   2 * Licensed under a two-clause BSD-style license.
   3 * See LICENSE for details.
   4 */
   5
   6#include "git-compat-util.h"
   7#include "line_buffer.h"
   8#include "svndiff.h"
   9
  10/*
  11 * svndiff0 applier
  12 *
  13 * See http://svn.apache.org/repos/asf/subversion/trunk/notes/svndiff.
  14 *
  15 * svndiff0 ::= 'SVN\0' window*
  16 */
  17
  18static int error_short_read(struct line_buffer *input)
  19{
  20        if (buffer_ferror(input))
  21                return error("error reading delta: %s", strerror(errno));
  22        return error("invalid delta: unexpected end of file");
  23}
  24
  25static int read_magic(struct line_buffer *in, off_t *len)
  26{
  27        static const char magic[] = {'S', 'V', 'N', '\0'};
  28        struct strbuf sb = STRBUF_INIT;
  29
  30        if (*len < sizeof(magic) ||
  31            buffer_read_binary(in, &sb, sizeof(magic)) != sizeof(magic))
  32                return error_short_read(in);
  33
  34        if (memcmp(sb.buf, magic, sizeof(magic)))
  35                return error("invalid delta: unrecognized file type");
  36
  37        *len -= sizeof(magic);
  38        strbuf_release(&sb);
  39        return 0;
  40}
  41
  42int svndiff0_apply(struct line_buffer *delta, off_t delta_len,
  43                        struct sliding_view *preimage, FILE *postimage)
  44{
  45        assert(delta && preimage && postimage);
  46
  47        if (read_magic(delta, &delta_len))
  48                return -1;
  49        if (delta_len)
  50                return error("What do you think I am?  A delta applier?");
  51        return 0;
  52}