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
rewind()22 bool AssetStreamAdaptor::rewind() {
23 off64_t pos = fAsset->seek(0, SEEK_SET);
24 if (pos == (off64_t)-1) {
25 SkDebugf("----- fAsset->seek(rewind) failed\n");
26 return false;
27 }
28 return true;
29 }
30
read(void * buffer,size_t size)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 off64_t oldOffset = fAsset->seek(0, SEEK_CUR);
42 if (-1 == oldOffset) {
43 SkDebugf("---- fAsset->seek(oldOffset) failed\n");
44 return 0;
45 }
46 off64_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
nullObjectReturn(const char msg[])65 jobject android::nullObjectReturn(const char msg[]) {
66 if (msg) {
67 SkDebugf("--- %s\n", msg);
68 }
69 return NULL;
70 }
71