Thu, 22 Jan 2015 13:21:57 +0100
Incorporate requested changes from Mozilla in review:
https://bugzilla.mozilla.org/show_bug.cgi?id=1123480#c6
1 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
2 * This Source Code Form is subject to the terms of the Mozilla Public
3 * License, v. 2.0. If a copy of the MPL was not distributed with this
4 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
6 #include "imgIEncoder.h"
8 #include "mozilla/ReentrantMonitor.h"
9 #include "mozilla/Attributes.h"
11 #include "nsCOMPtr.h"
13 // needed for JPEG library
14 #include <stdio.h>
16 extern "C" {
17 #include "jpeglib.h"
18 }
20 #define NS_JPEGENCODER_CID \
21 { /* ac2bb8fe-eeeb-4572-b40f-be03932b56e0 */ \
22 0xac2bb8fe, \
23 0xeeeb, \
24 0x4572, \
25 {0xb4, 0x0f, 0xbe, 0x03, 0x93, 0x2b, 0x56, 0xe0} \
26 }
28 // Provides JPEG encoding functionality. Use InitFromData() to do the
29 // encoding. See that function definition for encoding options.
31 class nsJPEGEncoder MOZ_FINAL : public imgIEncoder
32 {
33 typedef mozilla::ReentrantMonitor ReentrantMonitor;
34 public:
35 NS_DECL_THREADSAFE_ISUPPORTS
36 NS_DECL_IMGIENCODER
37 NS_DECL_NSIINPUTSTREAM
38 NS_DECL_NSIASYNCINPUTSTREAM
40 nsJPEGEncoder();
42 private:
43 ~nsJPEGEncoder();
45 protected:
47 void ConvertHostARGBRow(const uint8_t* aSrc, uint8_t* aDest,
48 uint32_t aPixelWidth);
49 void ConvertRGBARow(const uint8_t* aSrc, uint8_t* aDest, uint32_t aPixelWidth);
51 static void initDestination(jpeg_compress_struct* cinfo);
52 static boolean emptyOutputBuffer(jpeg_compress_struct* cinfo);
53 static void termDestination(jpeg_compress_struct* cinfo);
55 static void errorExit(jpeg_common_struct* cinfo);
57 void NotifyListener();
59 bool mFinished;
61 // image buffer
62 uint8_t* mImageBuffer;
63 uint32_t mImageBufferSize;
64 uint32_t mImageBufferUsed;
66 uint32_t mImageBufferReadPoint;
68 nsCOMPtr<nsIInputStreamCallback> mCallback;
69 nsCOMPtr<nsIEventTarget> mCallbackTarget;
70 uint32_t mNotifyThreshold;
72 /*
73 nsJPEGEncoder is designed to allow one thread to pump data into it while another
74 reads from it. We lock to ensure that the buffer remains append-only while
75 we read from it (that it is not realloced) and to ensure that only one thread
76 dispatches a callback for each call to AsyncWait.
77 */
78 ReentrantMonitor mReentrantMonitor;
79 };