| /* |
| * compress_lz4.c: LZ4 data compression routines |
| * |
| * ==================================================================== |
| * 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 <assert.h> |
| |
| #include "private/svn_subr_private.h" |
| |
| #include "svn_private_config.h" |
| |
| #ifdef SVN_INTERNAL_LZ4 |
| #include "lz4/lz4internal.h" |
| #else |
| #include <lz4.h> |
| #endif |
| |
| svn_error_t * |
| svn__compress_lz4(const void *data, apr_size_t len, |
| svn_stringbuf_t *out) |
| { |
| apr_size_t hdrlen; |
| unsigned char buf[SVN__MAX_ENCODED_UINT_LEN]; |
| unsigned char *p; |
| int compressed_data_len; |
| int max_compressed_data_len; |
| |
| assert(len <= LZ4_MAX_INPUT_SIZE); |
| |
| p = svn__encode_uint(buf, (apr_uint64_t)len); |
| hdrlen = p - buf; |
| max_compressed_data_len = LZ4_compressBound((int)len); |
| svn_stringbuf_setempty(out); |
| svn_stringbuf_ensure(out, max_compressed_data_len + hdrlen); |
| svn_stringbuf_appendbytes(out, (const char *)buf, hdrlen); |
| compressed_data_len = LZ4_compress_default(data, out->data + out->len, |
| (int)len, max_compressed_data_len); |
| if (!compressed_data_len) |
| return svn_error_create(SVN_ERR_LZ4_COMPRESSION_FAILED, NULL, NULL); |
| |
| if (compressed_data_len >= (int)len) |
| { |
| /* Compression didn't help :(, just append the original text */ |
| svn_stringbuf_appendbytes(out, data, len); |
| } |
| else |
| { |
| out->len += compressed_data_len; |
| out->data[out->len] = 0; |
| } |
| |
| return SVN_NO_ERROR; |
| } |
| |
| svn_error_t * |
| svn__decompress_lz4(const void *data, apr_size_t len, |
| svn_stringbuf_t *out, |
| apr_size_t limit) |
| { |
| apr_size_t hdrlen; |
| int compressed_data_len; |
| int decompressed_data_len; |
| apr_uint64_t u64; |
| const unsigned char *p = data; |
| int rv; |
| |
| assert(len <= INT_MAX); |
| assert(limit <= INT_MAX); |
| |
| /* First thing in the string is the original length. */ |
| p = svn__decode_uint(&u64, p, p + len); |
| if (p == NULL) |
| return svn_error_create(SVN_ERR_SVNDIFF_INVALID_COMPRESSED_DATA, NULL, |
| _("Decompression of compressed data failed: " |
| "no size")); |
| if (u64 > limit) |
| return svn_error_create(SVN_ERR_SVNDIFF_INVALID_COMPRESSED_DATA, NULL, |
| _("Decompression of compressed data failed: " |
| "size too large")); |
| decompressed_data_len = (int)u64; |
| hdrlen = p - (const unsigned char *)data; |
| compressed_data_len = (int)(len - hdrlen); |
| |
| svn_stringbuf_setempty(out); |
| svn_stringbuf_ensure(out, decompressed_data_len); |
| |
| if (compressed_data_len == decompressed_data_len) |
| { |
| /* Data is in the original, uncompressed form. */ |
| memcpy(out->data, p, decompressed_data_len); |
| } |
| else |
| { |
| rv = LZ4_decompress_safe((const char *)p, out->data, compressed_data_len, |
| decompressed_data_len); |
| if (rv < 0) |
| return svn_error_create(SVN_ERR_LZ4_DECOMPRESSION_FAILED, NULL, NULL); |
| |
| if (rv != decompressed_data_len) |
| return svn_error_create(SVN_ERR_SVNDIFF_INVALID_COMPRESSED_DATA, |
| NULL, |
| _("Size of uncompressed data " |
| "does not match stored original length")); |
| } |
| |
| out->data[decompressed_data_len] = 0; |
| out->len = decompressed_data_len; |
| |
| return SVN_NO_ERROR; |
| } |
| |
| const char * |
| svn_lz4__compiled_version(void) |
| { |
| static const char lz4_version_str[] = APR_STRINGIFY(LZ4_VERSION_MAJOR) "." \ |
| APR_STRINGIFY(LZ4_VERSION_MINOR) "." \ |
| APR_STRINGIFY(LZ4_VERSION_RELEASE); |
| |
| return lz4_version_str; |
| } |
| |
| int |
| svn_lz4__runtime_version(void) |
| { |
| return LZ4_versionNumber(); |
| } |