| Joseph Wen | f1f48bc | 2010-07-19 16:59:51 +0800 | [diff] [blame] | 1 | #include "AutoDecodeCancel.h" |
| 2 | |
| 3 | static SkMutex gAutoDecoderCancelMutex; |
| 4 | static AutoDecoderCancel* gAutoDecoderCancel; |
| 5 | #ifdef SK_DEBUG |
| 6 | static int gAutoDecoderCancelCount; |
| 7 | #endif |
| 8 | |
| 9 | AutoDecoderCancel::AutoDecoderCancel(jobject joptions, |
| 10 | SkImageDecoder* decoder) { |
| 11 | fJOptions = joptions; |
| 12 | fDecoder = decoder; |
| 13 | |
| 14 | if (NULL != joptions) { |
| 15 | SkAutoMutexAcquire ac(gAutoDecoderCancelMutex); |
| 16 | |
| 17 | // Add us as the head of the list |
| 18 | fPrev = NULL; |
| 19 | fNext = gAutoDecoderCancel; |
| 20 | if (gAutoDecoderCancel) { |
| 21 | gAutoDecoderCancel->fPrev = this; |
| 22 | } |
| 23 | gAutoDecoderCancel = this; |
| 24 | |
| 25 | SkDEBUGCODE(gAutoDecoderCancelCount += 1;) |
| 26 | Validate(); |
| 27 | } |
| 28 | } |
| 29 | |
| 30 | AutoDecoderCancel::~AutoDecoderCancel() { |
| 31 | if (NULL != fJOptions) { |
| 32 | SkAutoMutexAcquire ac(gAutoDecoderCancelMutex); |
| 33 | |
| 34 | // take us out of the dllist |
| 35 | AutoDecoderCancel* prev = fPrev; |
| 36 | AutoDecoderCancel* next = fNext; |
| 37 | |
| 38 | if (prev) { |
| 39 | SkASSERT(prev->fNext == this); |
| 40 | prev->fNext = next; |
| 41 | } else { |
| 42 | SkASSERT(gAutoDecoderCancel == this); |
| 43 | gAutoDecoderCancel = next; |
| 44 | } |
| 45 | if (next) { |
| 46 | SkASSERT(next->fPrev == this); |
| 47 | next->fPrev = prev; |
| 48 | } |
| 49 | |
| 50 | SkDEBUGCODE(gAutoDecoderCancelCount -= 1;) |
| 51 | Validate(); |
| 52 | } |
| 53 | } |
| 54 | |
| 55 | bool AutoDecoderCancel::RequestCancel(jobject joptions) { |
| 56 | SkAutoMutexAcquire ac(gAutoDecoderCancelMutex); |
| 57 | |
| 58 | Validate(); |
| 59 | |
| 60 | AutoDecoderCancel* pair = gAutoDecoderCancel; |
| 61 | while (pair != NULL) { |
| 62 | if (pair->fJOptions == joptions) { |
| 63 | pair->fDecoder->cancelDecode(); |
| 64 | return true; |
| 65 | } |
| 66 | pair = pair->fNext; |
| 67 | } |
| 68 | return false; |
| 69 | } |
| 70 | |
| 71 | #ifdef SK_DEBUG |
| 72 | // can only call this inside a lock on gAutoDecoderCancelMutex |
| 73 | void AutoDecoderCancel::Validate() { |
| 74 | const int gCount = gAutoDecoderCancelCount; |
| 75 | |
| 76 | if (gCount == 0) { |
| 77 | SkASSERT(gAutoDecoderCancel == NULL); |
| 78 | } else { |
| 79 | SkASSERT(gCount > 0); |
| 80 | |
| 81 | AutoDecoderCancel* curr = gAutoDecoderCancel; |
| 82 | SkASSERT(curr); |
| 83 | SkASSERT(curr->fPrev == NULL); |
| 84 | |
| 85 | int count = 0; |
| 86 | while (curr) { |
| 87 | count += 1; |
| 88 | SkASSERT(count <= gCount); |
| 89 | if (curr->fPrev) { |
| 90 | SkASSERT(curr->fPrev->fNext == curr); |
| 91 | } |
| 92 | if (curr->fNext) { |
| 93 | SkASSERT(curr->fNext->fPrev == curr); |
| 94 | } |
| 95 | curr = curr->fNext; |
| 96 | } |
| 97 | SkASSERT(count == gCount); |
| 98 | } |
| 99 | } |
| 100 | #endif |