/*
 * checksum-test.c:  tests checksum functions.
 *
 * ====================================================================
 *    Licensed to the Apache Software Foundation (ASF) under one
 *    or more contributor license agreements.  See the NOTICE file
 *    distributed with this work for additional information
 *    regarding copyright ownership.  The ASF licenses this file
 *    to you under the Apache License, Version 2.0 (the
 *    "License"); you may not use this file except in compliance
 *    with the License.  You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 *    Unless required by applicable law or agreed to in writing,
 *    software distributed under the License is distributed on an
 *    "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 *    KIND, either express or implied.  See the License for the
 *    specific language governing permissions and limitations
 *    under the License.
 * ====================================================================
 */

#include <apr_pools.h>

#include <zlib.h>

#include "svn_error.h"
#include "svn_io.h"
#include "private/svn_pseudo_md5.h"

#include "../svn_test.h"

static svn_error_t *
test_checksum_parse(apr_pool_t *pool)
{
  const char *md5_digest = "8518b76f7a45fe4de2d0955085b41f98";
  const char *sha1_digest = "74d82379bcc6771454377db03b912c2b62704139";
  const char *checksum_display;
  svn_checksum_t *checksum;

  SVN_ERR(svn_checksum_parse_hex(&checksum, svn_checksum_md5, md5_digest, pool));
  checksum_display = svn_checksum_to_cstring_display(checksum, pool);

  if (strcmp(checksum_display, md5_digest) != 0)
    return svn_error_createf
      (SVN_ERR_CHECKSUM_MISMATCH, NULL,
       "verify-checksum: md5 checksum mismatch:\n"
       "   expected:  %s\n"
       "     actual:  %s\n", md5_digest, checksum_display);

  SVN_ERR(svn_checksum_parse_hex(&checksum, svn_checksum_sha1, sha1_digest,
                                 pool));
  checksum_display = svn_checksum_to_cstring_display(checksum, pool);

  if (strcmp(checksum_display, sha1_digest) != 0)
    return svn_error_createf
      (SVN_ERR_CHECKSUM_MISMATCH, NULL,
       "verify-checksum: sha1 checksum mismatch:\n"
       "   expected:  %s\n"
       "     actual:  %s\n", sha1_digest, checksum_display);

  return SVN_NO_ERROR;
}

static svn_error_t *
test_checksum_empty(apr_pool_t *pool)
{
  svn_checksum_t *checksum;
  char data = '\0';

  checksum = svn_checksum_empty_checksum(svn_checksum_md5, pool);
  SVN_TEST_ASSERT(svn_checksum_is_empty_checksum(checksum));

  checksum = svn_checksum_empty_checksum(svn_checksum_sha1, pool);
  SVN_TEST_ASSERT(svn_checksum_is_empty_checksum(checksum));

  SVN_ERR(svn_checksum(&checksum, svn_checksum_md5, &data, 0, pool));
  SVN_TEST_ASSERT(svn_checksum_is_empty_checksum(checksum));

  SVN_ERR(svn_checksum(&checksum, svn_checksum_sha1, &data, 0, pool));
  SVN_TEST_ASSERT(svn_checksum_is_empty_checksum(checksum));

  return SVN_NO_ERROR;
}

static svn_error_t *
test_pseudo_md5(apr_pool_t *pool)
{
  apr_uint32_t input[16] = { 0 };
  apr_uint32_t digest_15[4] = { 0 };
  apr_uint32_t digest_31[4] = { 0 };
  apr_uint32_t digest_63[4] = { 0 };
  svn_checksum_t *checksum;

  /* input is all 0s but the hash shall be different
     (due to different input sizes)*/
  svn__pseudo_md5_15(digest_15, input);
  svn__pseudo_md5_31(digest_31, input);
  svn__pseudo_md5_63(digest_63, input);

  SVN_TEST_ASSERT(memcmp(digest_15, digest_31, sizeof(digest_15)));
  SVN_TEST_ASSERT(memcmp(digest_15, digest_63, sizeof(digest_15)));
  SVN_TEST_ASSERT(memcmp(digest_31, digest_63, sizeof(digest_15)));

  /* the checksums shall also be different from "proper" MD5 */
  SVN_ERR(svn_checksum(&checksum, svn_checksum_md5, input, 15, pool));
  SVN_TEST_ASSERT(memcmp(digest_15, checksum->digest, sizeof(digest_15)));

  SVN_ERR(svn_checksum(&checksum, svn_checksum_md5, input, 31, pool));
  SVN_TEST_ASSERT(memcmp(digest_31, checksum->digest, sizeof(digest_15)));

  SVN_ERR(svn_checksum(&checksum, svn_checksum_md5, input, 63, pool));
  SVN_TEST_ASSERT(memcmp(digest_63, checksum->digest, sizeof(digest_15)));

  return SVN_NO_ERROR;
}

static svn_error_t *
zero_match(apr_pool_t *pool)
{
  svn_checksum_t *zero_md5;
  svn_checksum_t *zero_sha1;
  svn_checksum_t *A_md5;
  svn_checksum_t *B_md5;
  svn_checksum_t *A_sha1;
  svn_checksum_t *B_sha1;


  zero_md5 = svn_checksum_create(svn_checksum_md5, pool);
  SVN_ERR(svn_checksum_clear(zero_md5));
  SVN_ERR(svn_checksum(&A_md5, svn_checksum_md5, "A", 1, pool));
  SVN_ERR(svn_checksum(&B_md5, svn_checksum_md5, "B", 1, pool));

  zero_sha1 = svn_checksum_create(svn_checksum_sha1, pool);
  SVN_ERR(svn_checksum_clear(zero_sha1));
  SVN_ERR(svn_checksum(&A_sha1, svn_checksum_sha1, "A", 1, pool));
  SVN_ERR(svn_checksum(&B_sha1, svn_checksum_sha1, "B", 1, pool));

  /* Different non-zero don't match. */
  SVN_TEST_ASSERT(!svn_checksum_match(A_md5, B_md5));
  SVN_TEST_ASSERT(!svn_checksum_match(A_sha1, B_sha1));
  SVN_TEST_ASSERT(!svn_checksum_match(A_md5, A_sha1));
  SVN_TEST_ASSERT(!svn_checksum_match(A_md5, B_sha1));

  /* Zero matches anything of the same kind. */
  SVN_TEST_ASSERT(svn_checksum_match(A_md5, zero_md5));
  SVN_TEST_ASSERT(svn_checksum_match(zero_md5, B_md5));
  SVN_TEST_ASSERT(svn_checksum_match(A_sha1, zero_sha1));
  SVN_TEST_ASSERT(svn_checksum_match(zero_sha1, B_sha1));

  /* Zero doesn't match anything of a different kind... */
  SVN_TEST_ASSERT(!svn_checksum_match(zero_md5, A_sha1));
  SVN_TEST_ASSERT(!svn_checksum_match(zero_sha1, A_md5));
  /* ...even another zero. */
  SVN_TEST_ASSERT(!svn_checksum_match(zero_md5, zero_sha1));

  return SVN_NO_ERROR;
}

static svn_error_t *
zlib_expansion_test(const svn_test_opts_t *opts,
                    apr_pool_t *pool)
{
  const char *data_path;
  svn_stringbuf_t *deflated;
  Byte dst_buffer[256 * 1024];
  Byte *src_buffer;
  apr_size_t sz;

  data_path = svn_dirent_join(opts->srcdir, "zlib.deflated", pool);

  SVN_ERR(svn_stringbuf_from_file2(&deflated, data_path, pool));
  src_buffer = (Byte*)deflated->data;

  /* Try to decompress the same data with different blocksizes */
  for (sz = 1; sz < 256; sz++)
    {
      z_stream stream;
      memset(&stream, 0, sizeof(stream));
      inflateInit2(&stream, -15 /* DEFLATE_WINDOW_SIZE */);

      stream.avail_in = sz;
      stream.next_in = src_buffer;
      stream.avail_out = sizeof(dst_buffer);
      stream.next_out = dst_buffer;

      do
        {
          int zr = inflate(&stream, Z_NO_FLUSH);

          if (zr != Z_OK && zr != Z_STREAM_END)
          {
              return svn_error_createf(
                          SVN_ERR_TEST_FAILED, NULL,
                          "Failure decompressing with blocksize %d", (int)sz);
          }
          stream.avail_in += sz;
      } while (stream.next_in + stream.avail_in  < src_buffer + deflated->len);

      stream.avail_in = (src_buffer + deflated->len) - stream.next_in;

      {
          int zr = inflate(&stream, Z_NO_FLUSH);

          if (zr != Z_STREAM_END)
            {
              return svn_error_createf(
                        SVN_ERR_TEST_FAILED, NULL,
                        "Final flush failed with blocksize %d", (int)sz);
            }

          zr = inflateEnd(&stream);

          if (zr != Z_OK)
            {
              return svn_error_createf(
                        SVN_ERR_TEST_FAILED, NULL,
                        "End of stream handling failed with blocksize %d",
                        (int)sz);
            }
      }

      {
          apr_uint32_t crc = crc32(0, dst_buffer, stream.total_out);

          if (stream.total_out != 242014 || crc != 0x8f03d934)
            {
              return svn_error_createf(
                  SVN_ERR_TEST_FAILED, NULL,
                  "Decompressed data doesn't match expected size or crc with "
                  "blocksize %d: Found crc32=0x%08x, size=%d.\n"
                  "Verify your ZLib installation, as this should never happen",
                  (int)sz, (unsigned)crc, (int)stream.total_out);
            }
      }
  }

  return SVN_NO_ERROR;
}

/* An array of all test functions */
struct svn_test_descriptor_t test_funcs[] =
  {
    SVN_TEST_NULL,
    SVN_TEST_PASS2(test_checksum_parse,
                   "checksum parse"),
    SVN_TEST_PASS2(test_checksum_empty,
                   "checksum emptiness"),
    SVN_TEST_PASS2(test_pseudo_md5,
                   "pseudo-md5 compatibility"),
    SVN_TEST_PASS2(zero_match,
                   "zero checksum matching"),
    SVN_TEST_OPTS_PASS(zlib_expansion_test,
                       "zlib expansion test (zlib regression)"),
    SVN_TEST_NULL
  };