Wei-Ta Chen | 6b849e2 | 2010-09-07 17:32:18 +0800 | [diff] [blame^] | 1 | /* |
| 2 | * Copyright (C) 2010 The Android Open Source Project |
| 3 | * |
| 4 | * Licensed under the Apache License, Version 2.0 (the "License"); |
| 5 | * you may not use this file except in compliance with the License. |
| 6 | * You may obtain a copy of the License at |
| 7 | * |
| 8 | * http://www.apache.org/licenses/LICENSE-2.0 |
| 9 | * |
| 10 | * Unless required by applicable law or agreed to in writing, software |
| 11 | * distributed under the License is distributed on an "AS IS" BASIS, |
| 12 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| 13 | * See the License for the specific language governing permissions and |
| 14 | * limitations under the License. |
| 15 | */ |
| 16 | |
| 17 | #include "Utils.h" |
| 18 | #include "SkUtils.h" |
| 19 | |
| 20 | using namespace android; |
| 21 | |
| 22 | bool AssetStreamAdaptor::rewind() { |
| 23 | off_t pos = fAsset->seek(0, SEEK_SET); |
| 24 | if (pos == (off_t)-1) { |
| 25 | SkDebugf("----- fAsset->seek(rewind) failed\n"); |
| 26 | return false; |
| 27 | } |
| 28 | return true; |
| 29 | } |
| 30 | |
| 31 | size_t AssetStreamAdaptor::read(void* buffer, size_t size) { |
| 32 | ssize_t amount; |
| 33 | |
| 34 | if (NULL == buffer) { |
| 35 | if (0 == size) { // caller is asking us for our total length |
| 36 | return fAsset->getLength(); |
| 37 | } |
| 38 | // asset->seek returns new total offset |
| 39 | // we want to return amount that was skipped |
| 40 | |
| 41 | off_t oldOffset = fAsset->seek(0, SEEK_CUR); |
| 42 | if (-1 == oldOffset) { |
| 43 | SkDebugf("---- fAsset->seek(oldOffset) failed\n"); |
| 44 | return 0; |
| 45 | } |
| 46 | off_t newOffset = fAsset->seek(size, SEEK_CUR); |
| 47 | if (-1 == newOffset) { |
| 48 | SkDebugf("---- fAsset->seek(%d) failed\n", size); |
| 49 | return 0; |
| 50 | } |
| 51 | amount = newOffset - oldOffset; |
| 52 | } else { |
| 53 | amount = fAsset->read(buffer, size); |
| 54 | if (amount <= 0) { |
| 55 | SkDebugf("---- fAsset->read(%d) returned %d\n", size, amount); |
| 56 | } |
| 57 | } |
| 58 | |
| 59 | if (amount < 0) { |
| 60 | amount = 0; |
| 61 | } |
| 62 | return amount; |
| 63 | } |
| 64 | |
| 65 | jobject android::nullObjectReturn(const char msg[]) { |
| 66 | if (msg) { |
| 67 | SkDebugf("--- %s\n", msg); |
| 68 | } |
| 69 | return NULL; |
| 70 | } |