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 <errno.h>
18 #include <unistd.h>
19 #include <stdio.h>
20 #include <fcntl.h>
21 #include <stdlib.h>
22 #include <string.h>
23 
24 #include <linux/fb.h>
25 #include <sys/ioctl.h>
26 #include <sys/mman.h>
27 
28 #include <binder/ProcessState.h>
29 
30 #include <gui/SurfaceComposerClient.h>
31 #include <gui/ISurfaceComposer.h>
32 
33 #include <ui/DisplayInfo.h>
34 #include <ui/PixelFormat.h>
35 
36 // TODO: Fix Skia.
37 #pragma GCC diagnostic push
38 #pragma GCC diagnostic ignored "-Wunused-parameter"
39 #include <SkImageEncoder.h>
40 #include <SkData.h>
41 #pragma GCC diagnostic pop
42 
43 using namespace android;
44 
45 static uint32_t DEFAULT_DISPLAY_ID = ISurfaceComposer::eDisplayIdMain;
46 
usage(const char * pname)47 static void usage(const char* pname)
48 {
49     fprintf(stderr,
50             "usage: %s [-hp] [-d display-id] [FILENAME]\n"
51             "   -h: this message\n"
52             "   -p: save the file as a png.\n"
53             "   -d: specify the display id to capture, default %d.\n"
54             "If FILENAME ends with .png it will be saved as a png.\n"
55             "If FILENAME is not given, the results will be printed to stdout.\n",
56             pname, DEFAULT_DISPLAY_ID
57     );
58 }
59 
flinger2skia(PixelFormat f)60 static SkColorType flinger2skia(PixelFormat f)
61 {
62     switch (f) {
63         case PIXEL_FORMAT_RGB_565:
64             return kRGB_565_SkColorType;
65         default:
66             return kN32_SkColorType;
67     }
68 }
69 
notifyMediaScanner(const char * fileName)70 static status_t notifyMediaScanner(const char* fileName) {
71     String8 cmd("am broadcast -a android.intent.action.MEDIA_SCANNER_SCAN_FILE -d file://");
72     String8 fileUrl("\"");
73     fileUrl.append(fileName);
74     fileUrl.append("\"");
75     cmd.append(fileName);
76     cmd.append(" > /dev/null");
77     int result = system(cmd.string());
78     if (result < 0) {
79         fprintf(stderr, "Unable to broadcast intent for media scanner.\n");
80         return UNKNOWN_ERROR;
81     }
82     return NO_ERROR;
83 }
84 
main(int argc,char ** argv)85 int main(int argc, char** argv)
86 {
87     // setThreadPoolMaxThreadCount(0) actually tells the kernel it's
88     // not allowed to spawn any additional threads, but we still spawn
89     // a binder thread from userspace when we call startThreadPool().
90     // See b/36066697 for rationale
91     ProcessState::self()->setThreadPoolMaxThreadCount(0);
92     ProcessState::self()->startThreadPool();
93 
94     const char* pname = argv[0];
95     bool png = false;
96     int32_t displayId = DEFAULT_DISPLAY_ID;
97     int c;
98     while ((c = getopt(argc, argv, "phd:")) != -1) {
99         switch (c) {
100             case 'p':
101                 png = true;
102                 break;
103             case 'd':
104                 displayId = atoi(optarg);
105                 break;
106             case '?':
107             case 'h':
108                 usage(pname);
109                 return 1;
110         }
111     }
112     argc -= optind;
113     argv += optind;
114 
115     int fd = -1;
116     const char* fn = NULL;
117     if (argc == 0) {
118         fd = dup(STDOUT_FILENO);
119     } else if (argc == 1) {
120         fn = argv[0];
121         fd = open(fn, O_WRONLY | O_CREAT | O_TRUNC, 0664);
122         if (fd == -1) {
123             fprintf(stderr, "Error opening file: %s (%s)\n", fn, strerror(errno));
124             return 1;
125         }
126         const int len = strlen(fn);
127         if (len >= 4 && 0 == strcmp(fn+len-4, ".png")) {
128             png = true;
129         }
130     }
131 
132     if (fd == -1) {
133         usage(pname);
134         return 1;
135     }
136 
137     void const* mapbase = MAP_FAILED;
138     ssize_t mapsize = -1;
139 
140     void const* base = NULL;
141     uint32_t w, s, h, f;
142     size_t size = 0;
143 
144     // Maps orientations from DisplayInfo to ISurfaceComposer
145     static const uint32_t ORIENTATION_MAP[] = {
146         ISurfaceComposer::eRotateNone, // 0 == DISPLAY_ORIENTATION_0
147         ISurfaceComposer::eRotate270, // 1 == DISPLAY_ORIENTATION_90
148         ISurfaceComposer::eRotate180, // 2 == DISPLAY_ORIENTATION_180
149         ISurfaceComposer::eRotate90, // 3 == DISPLAY_ORIENTATION_270
150     };
151 
152     ScreenshotClient screenshot;
153     sp<IBinder> display = SurfaceComposerClient::getBuiltInDisplay(displayId);
154     if (display == NULL) {
155         fprintf(stderr, "Unable to get handle for display %d\n", displayId);
156         return 1;
157     }
158 
159     Vector<DisplayInfo> configs;
160     SurfaceComposerClient::getDisplayConfigs(display, &configs);
161     int activeConfig = SurfaceComposerClient::getActiveConfig(display);
162     if (static_cast<size_t>(activeConfig) >= configs.size()) {
163         fprintf(stderr, "Active config %d not inside configs (size %zu)\n",
164                 activeConfig, configs.size());
165         return 1;
166     }
167     uint8_t displayOrientation = configs[activeConfig].orientation;
168     uint32_t captureOrientation = ORIENTATION_MAP[displayOrientation];
169 
170     status_t result = screenshot.update(display, Rect(),
171             0 /* reqWidth */, 0 /* reqHeight */,
172             INT32_MIN, INT32_MAX, /* all layers */
173             false, captureOrientation);
174     if (result == NO_ERROR) {
175         base = screenshot.getPixels();
176         w = screenshot.getWidth();
177         h = screenshot.getHeight();
178         s = screenshot.getStride();
179         f = screenshot.getFormat();
180         size = screenshot.getSize();
181     }
182 
183     if (base != NULL) {
184         if (png) {
185             const SkImageInfo info =
186                 SkImageInfo::Make(w, h, flinger2skia(f), kPremul_SkAlphaType);
187             SkPixmap pixmap(info, base, s * bytesPerPixel(f));
188             struct FDWStream final : public SkWStream {
189               size_t fBytesWritten = 0;
190               int fFd;
191               FDWStream(int f) : fFd(f) {}
192               size_t bytesWritten() const override { return fBytesWritten; }
193               bool write(const void* buffer, size_t size) override {
194                 fBytesWritten += size;
195                 return size == 0 || ::write(fFd, buffer, size) > 0;
196               }
197             } fdStream(fd);
198             (void)SkEncodeImage(&fdStream, pixmap, SkEncodedImageFormat::kPNG, 100);
199             if (fn != NULL) {
200                 notifyMediaScanner(fn);
201             }
202         } else {
203             write(fd, &w, 4);
204             write(fd, &h, 4);
205             write(fd, &f, 4);
206             size_t Bpp = bytesPerPixel(f);
207             for (size_t y=0 ; y<h ; y++) {
208                 write(fd, base, w*Bpp);
209                 base = (void *)((char *)base + s*Bpp);
210             }
211         }
212     }
213     close(fd);
214     if (mapbase != MAP_FAILED) {
215         munmap((void *)mapbase, mapsize);
216     }
217 
218     // b/36066697: Avoid running static destructors.
219     _exit(0);
220 }
221