Utils.cpp revision 6b849e2123be98eb2a1a25b8abf0b13a279ce952
116c9d6a92e1b86d448c00c52a1630f3e71e6df76John Reck/* 216c9d6a92e1b86d448c00c52a1630f3e71e6df76John Reck * Copyright (C) 2010 The Android Open Source Project 316c9d6a92e1b86d448c00c52a1630f3e71e6df76John Reck * 416c9d6a92e1b86d448c00c52a1630f3e71e6df76John Reck * Licensed under the Apache License, Version 2.0 (the "License"); 516c9d6a92e1b86d448c00c52a1630f3e71e6df76John Reck * you may not use this file except in compliance with the License. 616c9d6a92e1b86d448c00c52a1630f3e71e6df76John Reck * You may obtain a copy of the License at 716c9d6a92e1b86d448c00c52a1630f3e71e6df76John Reck * 816c9d6a92e1b86d448c00c52a1630f3e71e6df76John Reck * http://www.apache.org/licenses/LICENSE-2.0 916c9d6a92e1b86d448c00c52a1630f3e71e6df76John Reck * 1016c9d6a92e1b86d448c00c52a1630f3e71e6df76John Reck * Unless required by applicable law or agreed to in writing, software 1116c9d6a92e1b86d448c00c52a1630f3e71e6df76John Reck * distributed under the License is distributed on an "AS IS" BASIS, 1216c9d6a92e1b86d448c00c52a1630f3e71e6df76John Reck * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 1316c9d6a92e1b86d448c00c52a1630f3e71e6df76John Reck * See the License for the specific language governing permissions and 1416c9d6a92e1b86d448c00c52a1630f3e71e6df76John Reck * limitations under the License. 1516c9d6a92e1b86d448c00c52a1630f3e71e6df76John Reck */ 1616c9d6a92e1b86d448c00c52a1630f3e71e6df76John Reck 1716c9d6a92e1b86d448c00c52a1630f3e71e6df76John Reck#include "Utils.h" 1854fa17f667c285a5c9225e238c8132dfe830ef36Chris Craik#include "SkUtils.h" 1916c9d6a92e1b86d448c00c52a1630f3e71e6df76John Reck 2016c9d6a92e1b86d448c00c52a1630f3e71e6df76John Reckusing namespace android; 2116c9d6a92e1b86d448c00c52a1630f3e71e6df76John Reck 2227e58b4f54d693ff1db7ab2edb5d47ca296c1278Chris Craikbool AssetStreamAdaptor::rewind() { 2316c9d6a92e1b86d448c00c52a1630f3e71e6df76John Reck off_t pos = fAsset->seek(0, SEEK_SET); 2416c9d6a92e1b86d448c00c52a1630f3e71e6df76John Reck if (pos == (off_t)-1) { 2516c9d6a92e1b86d448c00c52a1630f3e71e6df76John Reck SkDebugf("----- fAsset->seek(rewind) failed\n"); 2627e58b4f54d693ff1db7ab2edb5d47ca296c1278Chris Craik return false; 2716c9d6a92e1b86d448c00c52a1630f3e71e6df76John Reck } 2816c9d6a92e1b86d448c00c52a1630f3e71e6df76John Reck return true; 2916c9d6a92e1b86d448c00c52a1630f3e71e6df76John Reck} 3016c9d6a92e1b86d448c00c52a1630f3e71e6df76John Reck 3116c9d6a92e1b86d448c00c52a1630f3e71e6df76John Recksize_t AssetStreamAdaptor::read(void* buffer, size_t size) { 3216c9d6a92e1b86d448c00c52a1630f3e71e6df76John Reck ssize_t amount; 3354fa17f667c285a5c9225e238c8132dfe830ef36Chris Craik 3454fa17f667c285a5c9225e238c8132dfe830ef36Chris Craik if (NULL == buffer) { 3554fa17f667c285a5c9225e238c8132dfe830ef36Chris Craik if (0 == size) { // caller is asking us for our total length 3654fa17f667c285a5c9225e238c8132dfe830ef36Chris Craik return fAsset->getLength(); 3716c9d6a92e1b86d448c00c52a1630f3e71e6df76John Reck } 3816c9d6a92e1b86d448c00c52a1630f3e71e6df76John Reck // asset->seek returns new total offset 3916c9d6a92e1b86d448c00c52a1630f3e71e6df76John Reck // we want to return amount that was skipped 4016c9d6a92e1b86d448c00c52a1630f3e71e6df76John Reck 4116c9d6a92e1b86d448c00c52a1630f3e71e6df76John Reck off_t oldOffset = fAsset->seek(0, SEEK_CUR); 4254fa17f667c285a5c9225e238c8132dfe830ef36Chris Craik if (-1 == oldOffset) { 4316c9d6a92e1b86d448c00c52a1630f3e71e6df76John Reck SkDebugf("---- fAsset->seek(oldOffset) failed\n"); 4416c9d6a92e1b86d448c00c52a1630f3e71e6df76John Reck return 0; 4516c9d6a92e1b86d448c00c52a1630f3e71e6df76John Reck } 4616c9d6a92e1b86d448c00c52a1630f3e71e6df76John Reck off_t newOffset = fAsset->seek(size, SEEK_CUR); 4716c9d6a92e1b86d448c00c52a1630f3e71e6df76John Reck if (-1 == newOffset) { 4816c9d6a92e1b86d448c00c52a1630f3e71e6df76John Reck SkDebugf("---- fAsset->seek(%d) failed\n", size); 4916c9d6a92e1b86d448c00c52a1630f3e71e6df76John Reck return 0; 5016c9d6a92e1b86d448c00c52a1630f3e71e6df76John Reck } 5116c9d6a92e1b86d448c00c52a1630f3e71e6df76John Reck amount = newOffset - oldOffset; 5216c9d6a92e1b86d448c00c52a1630f3e71e6df76John Reck } else { 5316c9d6a92e1b86d448c00c52a1630f3e71e6df76John Reck amount = fAsset->read(buffer, size); 5416c9d6a92e1b86d448c00c52a1630f3e71e6df76John Reck if (amount <= 0) { 5516c9d6a92e1b86d448c00c52a1630f3e71e6df76John Reck SkDebugf("---- fAsset->read(%d) returned %d\n", size, amount); 5616c9d6a92e1b86d448c00c52a1630f3e71e6df76John Reck } 5716c9d6a92e1b86d448c00c52a1630f3e71e6df76John Reck } 5816c9d6a92e1b86d448c00c52a1630f3e71e6df76John Reck 5916c9d6a92e1b86d448c00c52a1630f3e71e6df76John Reck if (amount < 0) { 6016c9d6a92e1b86d448c00c52a1630f3e71e6df76John Reck amount = 0; 6116c9d6a92e1b86d448c00c52a1630f3e71e6df76John Reck } 6216c9d6a92e1b86d448c00c52a1630f3e71e6df76John Reck return amount; 6316c9d6a92e1b86d448c00c52a1630f3e71e6df76John Reck} 6416c9d6a92e1b86d448c00c52a1630f3e71e6df76John Reck 6516c9d6a92e1b86d448c00c52a1630f3e71e6df76John Reckjobject android::nullObjectReturn(const char msg[]) { 6616c9d6a92e1b86d448c00c52a1630f3e71e6df76John Reck if (msg) { 6754fa17f667c285a5c9225e238c8132dfe830ef36Chris Craik SkDebugf("--- %s\n", msg); 6816c9d6a92e1b86d448c00c52a1630f3e71e6df76John Reck } 6916c9d6a92e1b86d448c00c52a1630f3e71e6df76John Reck return NULL; 7016c9d6a92e1b86d448c00c52a1630f3e71e6df76John Reck} 7116c9d6a92e1b86d448c00c52a1630f3e71e6df76John Reck