Generalize physical display management

This CL enables the framework to manage an arbitrary number of physical
displays. It also surfaces physical display IDs, which are stable across
reboots and encode (model, port) information that will be propagated
further up in a follow-up CL.

Bug: 116025192
Test: Boot with more than two displays
Test: Hotplug works with any number of displays
Test: Verify stable display IDs with "dumpsys display"
Change-Id: Idb2eaff66b2e0873be6ad27d337ff18b730d1331

1 files changed, 18 insertions, 13 deletions

diff --git a/cmds/screencap/screencap.cpp b/cmds/screencap/screencap.cpp
index 3d74f8b207af..c4976675dc04 100644
--- a/cmds/screencap/screencap.cpp
+++ b/cmds/screencap/screencap.cpp
@@ -46,23 +46,22 @@
 
 using namespace android;
 
-static uint32_t DEFAULT_DISPLAY_ID = ISurfaceComposer::eDisplayIdMain;
-
 #define COLORSPACE_UNKNOWN    0
 #define COLORSPACE_SRGB       1
 #define COLORSPACE_DISPLAY_P3 2
 
-static void usage(const char* pname)
+static void usage(const char* pname, PhysicalDisplayId displayId)
 {
     fprintf(stderr,
             "usage: %s [-hp] [-d display-id] [FILENAME]\n"
             "   -h: this message\n"
             "   -p: save the file as a png.\n"
-            "   -d: specify the display id to capture, default %d.\n"
+            "   -d: specify the physical display ID to capture (default: %"
+                    ANDROID_PHYSICAL_DISPLAY_ID_FORMAT ")\n"
+            "       see \"dumpsys SurfaceFlinger --display-id\" for valid display IDs.\n"
             "If FILENAME ends with .png it will be saved as a png.\n"
             "If FILENAME is not given, the results will be printed to stdout.\n",
-            pname, DEFAULT_DISPLAY_ID
-    );
+            pname, displayId);
 }
 
 static SkColorType flinger2skia(PixelFormat f)
@@ -127,9 +126,14 @@ static status_t notifyMediaScanner(const char* fileName) {
 
 int main(int argc, char** argv)
 {
+    std::optional<PhysicalDisplayId> displayId = SurfaceComposerClient::getInternalDisplayId();
+    if (!displayId) {
+        fprintf(stderr, "Failed to get token for internal display\n");
+        return 1;
+    }
+
     const char* pname = argv[0];
     bool png = false;
-    int32_t displayId = DEFAULT_DISPLAY_ID;
     int c;
     while ((c = getopt(argc, argv, "phd:")) != -1) {
         switch (c) {
@@ -137,11 +141,11 @@ int main(int argc, char** argv)
                 png = true;
                 break;
             case 'd':
-                displayId = atoi(optarg);
+                displayId = atoll(optarg);
                 break;
             case '?':
             case 'h':
-                usage(pname);
+                usage(pname, *displayId);
                 return 1;
         }
     }
@@ -166,7 +170,7 @@ int main(int argc, char** argv)
     }
 
     if (fd == -1) {
-        usage(pname);
+        usage(pname, *displayId);
         return 1;
     }
 
@@ -192,9 +196,10 @@ int main(int argc, char** argv)
     ProcessState::self()->setThreadPoolMaxThreadCount(0);
     ProcessState::self()->startThreadPool();
 
-    sp<IBinder> display = SurfaceComposerClient::getBuiltInDisplay(displayId);
-    if (display == NULL) {
-        fprintf(stderr, "Unable to get handle for display %d\n", displayId);
+    const sp<IBinder> display = SurfaceComposerClient::getPhysicalDisplayToken(*displayId);
+    if (display == nullptr) {
+        fprintf(stderr, "Failed to get token for invalid display %"
+                ANDROID_PHYSICAL_DISPLAY_ID_FORMAT "\n", *displayId);
         return 1;
     }