michael@0: 
michael@0: /*
michael@0:  * Copyright 2010 The Android Open Source Project
michael@0:  *
michael@0:  * Use of this source code is governed by a BSD-style license that can be
michael@0:  * found in the LICENSE file.
michael@0:  */
michael@0: 
michael@0: 
michael@0: #include "SkData.h"
michael@0: #include "SkFlate.h"
michael@0: #include "SkStream.h"
michael@0: 
michael@0: #ifndef SK_HAS_ZLIB
michael@0: bool SkFlate::HaveFlate() { return false; }
michael@0: bool SkFlate::Deflate(SkStream*, SkWStream*) { return false; }
michael@0: bool SkFlate::Deflate(const void*, size_t, SkWStream*) { return false; }
michael@0: bool SkFlate::Deflate(const SkData*, SkWStream*) { return false; }
michael@0: bool SkFlate::Inflate(SkStream*, SkWStream*) { return false; }
michael@0: #else
michael@0: 
michael@0: // static
michael@0: bool SkFlate::HaveFlate() {
michael@0:     return true;
michael@0: }
michael@0: 
michael@0: namespace {
michael@0: 
michael@0: #ifdef SK_SYSTEM_ZLIB
michael@0: #include <zlib.h>
michael@0: #else
michael@0: #include SK_ZLIB_INCLUDE
michael@0: #endif
michael@0: 
michael@0: // static
michael@0: const size_t kBufferSize = 1024;
michael@0: 
michael@0: bool doFlate(bool compress, SkStream* src, SkWStream* dst) {
michael@0:     uint8_t inputBuffer[kBufferSize];
michael@0:     uint8_t outputBuffer[kBufferSize];
michael@0:     z_stream flateData;
michael@0:     flateData.zalloc = NULL;
michael@0:     flateData.zfree = NULL;
michael@0:     flateData.next_in = NULL;
michael@0:     flateData.avail_in = 0;
michael@0:     flateData.next_out = outputBuffer;
michael@0:     flateData.avail_out = kBufferSize;
michael@0:     int rc;
michael@0:     if (compress)
michael@0:         rc = deflateInit(&flateData, Z_DEFAULT_COMPRESSION);
michael@0:     else
michael@0:         rc = inflateInit(&flateData);
michael@0:     if (rc != Z_OK)
michael@0:         return false;
michael@0: 
michael@0:     uint8_t* input = (uint8_t*)src->getMemoryBase();
michael@0:     size_t inputLength = src->getLength();
michael@0:     if (input == NULL || inputLength == 0) {
michael@0:         input = NULL;
michael@0:         flateData.next_in = inputBuffer;
michael@0:         flateData.avail_in = 0;
michael@0:     } else {
michael@0:         flateData.next_in = input;
michael@0:         flateData.avail_in = SkToUInt(inputLength);
michael@0:     }
michael@0: 
michael@0:     rc = Z_OK;
michael@0:     while (true) {
michael@0:         if (flateData.avail_out < kBufferSize) {
michael@0:             if (!dst->write(outputBuffer, kBufferSize - flateData.avail_out)) {
michael@0:                 rc = Z_BUF_ERROR;
michael@0:                 break;
michael@0:             }
michael@0:             flateData.next_out = outputBuffer;
michael@0:             flateData.avail_out = kBufferSize;
michael@0:         }
michael@0:         if (rc != Z_OK)
michael@0:             break;
michael@0:         if (flateData.avail_in == 0) {
michael@0:             if (input != NULL)
michael@0:                 break;
michael@0:             size_t read = src->read(&inputBuffer, kBufferSize);
michael@0:             if (read == 0)
michael@0:                 break;
michael@0:             flateData.next_in = inputBuffer;
michael@0:             flateData.avail_in = SkToUInt(read);
michael@0:         }
michael@0:         if (compress)
michael@0:             rc = deflate(&flateData, Z_NO_FLUSH);
michael@0:         else
michael@0:             rc = inflate(&flateData, Z_NO_FLUSH);
michael@0:     }
michael@0:     while (rc == Z_OK) {
michael@0:         if (compress)
michael@0:             rc = deflate(&flateData, Z_FINISH);
michael@0:         else
michael@0:             rc = inflate(&flateData, Z_FINISH);
michael@0:         if (flateData.avail_out < kBufferSize) {
michael@0:             if (!dst->write(outputBuffer, kBufferSize - flateData.avail_out))
michael@0:                 return false;
michael@0:             flateData.next_out = outputBuffer;
michael@0:             flateData.avail_out = kBufferSize;
michael@0:         }
michael@0:     }
michael@0: 
michael@0:     if (compress)
michael@0:         deflateEnd(&flateData);
michael@0:     else
michael@0:         inflateEnd(&flateData);
michael@0:     if (rc == Z_STREAM_END)
michael@0:         return true;
michael@0:     return false;
michael@0: }
michael@0: 
michael@0: }
michael@0: 
michael@0: // static
michael@0: bool SkFlate::Deflate(SkStream* src, SkWStream* dst) {
michael@0:     return doFlate(true, src, dst);
michael@0: }
michael@0: 
michael@0: bool SkFlate::Deflate(const void* ptr, size_t len, SkWStream* dst) {
michael@0:     SkMemoryStream stream(ptr, len);
michael@0:     return doFlate(true, &stream, dst);
michael@0: }
michael@0: 
michael@0: bool SkFlate::Deflate(const SkData* data, SkWStream* dst) {
michael@0:     if (data) {
michael@0:         SkMemoryStream stream(data->data(), data->size());
michael@0:         return doFlate(true, &stream, dst);
michael@0:     }
michael@0:     return false;
michael@0: }
michael@0: 
michael@0: // static
michael@0: bool SkFlate::Inflate(SkStream* src, SkWStream* dst) {
michael@0:     return doFlate(false, src, dst);
michael@0: }
michael@0: 
michael@0: #endif