bootanimation: performance enhancements

This patch implements two simple performance enhancements, which
might benefit devices. They are completely opt-in by setting
the following variables.

  * TARGET_BOOTANIMATION_PRELOAD: will preload the bootanimation
    zip to memory; this is handy on devices where the storage
    might be slow. By preloading it, we get quick access to the
    zip file, and the animation doesn't stutter.

  * TARGET_BOOTANIMATION_TEXTURE_CACHE: allows maintainers to
    force texture cache on/off.

Also fixes the sign warnings related to int / size_t comparison

Change-Id: Ie92d1b0aa90b43ba39c368a2a33657a60c3a64b5

2 files changed, 54 insertions, 4 deletions

diff --git a/cmds/bootanimation/Android.mk b/cmds/bootanimation/Android.mk
index 7d39912..7f1857d 100644
--- a/cmds/bootanimation/Android.mk
+++ b/cmds/bootanimation/Android.mk
@@ -20,6 +20,18 @@ LOCAL_SHARED_LIBRARIES := \
 LOCAL_C_INCLUDES := \
 	$(call include-path-for, corecg graphics)
 
+ifeq ($(TARGET_BOOTANIMATION_PRELOAD),true)
+    LOCAL_CFLAGS += -DPRELOAD_BOOTANIMATION
+endif
+
+ifeq ($(TARGET_BOOTANIMATION_TEXTURE_CACHE),true)
+    LOCAL_CFLAGS += -DNO_TEXTURE_CACHE=0
+endif
+
+ifeq ($(TARGET_BOOTANIMATION_TEXTURE_CACHE),false)
+    LOCAL_CFLAGS += -DNO_TEXTURE_CACHE=1
+endif
+
 LOCAL_MODULE:= bootanimation
 
 
diff --git a/cmds/bootanimation/BootAnimation.cpp b/cmds/bootanimation/BootAnimation.cpp
index d95184a..2f06ad5 100644
--- a/cmds/bootanimation/BootAnimation.cpp
+++ b/cmds/bootanimation/BootAnimation.cpp
@@ -281,6 +281,38 @@ status_t BootAnimation::readyToRun() {
         mAndroidAnimation = false;
     }
 
+
+#ifdef PRELOAD_BOOTANIMATION
+    // Preload the bootanimation zip on memory, so we don't stutter
+    // when showing the animation
+    FILE* fd;
+    if (encryptedAnimation && access(SYSTEM_ENCRYPTED_BOOTANIMATION_FILE, R_OK) == 0)
+        fd = fopen(SYSTEM_ENCRYPTED_BOOTANIMATION_FILE, "r");
+    else if (access(USER_BOOTANIMATION_FILE, R_OK) == 0)
+        fd = fopen(USER_BOOTANIMATION_FILE, "r");
+    else if (access(SYSTEM_BOOTANIMATION_FILE, R_OK) == 0)
+        fd = fopen(SYSTEM_BOOTANIMATION_FILE, "r");
+    else
+        return NO_ERROR;
+
+    if (fd != NULL) {
+        // We could use readahead..
+        // ... if bionic supported it :(
+        //readahead(fd, 0, INT_MAX);
+        void *crappyBuffer = malloc(2*1024*1024);
+        if (crappyBuffer != NULL) {
+            // Read all the zip
+            while (!feof(fd))
+                fread(crappyBuffer, 1024, 2*1024, fd);
+
+            free(crappyBuffer);
+        } else {
+            LOGW("Unable to allocate memory to preload the animation");
+        }
+        fclose(fd);
+    }
+#endif
+
     return NO_ERROR;
 }
 
@@ -420,7 +452,7 @@ bool BootAnimation::movie()
             const String8 path(entryName.getPathDir());
             const String8 leaf(entryName.getPathLeaf());
             if (leaf.size() > 0) {
-                for (int j=0 ; j<pcount ; j++) {
+                for (size_t j=0 ; j<pcount ; j++) {
                     if (path == animation.parts[j].path) {
                         int method;
                         // supports only stored png files
@@ -468,16 +500,22 @@ bool BootAnimation::movie()
     Region clearReg(Rect(mWidth, mHeight));
     clearReg.subtractSelf(Rect(xc, yc, xc+animation.width, yc+animation.height));
 
-    for (int i=0 ; i<pcount && !exitPending() ; i++) {
+    for (size_t i=0 ; i<pcount && !exitPending() ; i++) {
         const Animation::Part& part(animation.parts[i]);
         const size_t fcount = part.frames.size();
+
+        // can be 1, 0, or not set
+        #ifdef NO_TEXTURE_CACHE
+        const int noTextureCache = NO_TEXTURE_CACHE;
+        #else
         const int noTextureCache = ((animation.width * animation.height * fcount) >
                                  48 * 1024 * 1024) ? 1 : 0;
+        #endif
 
         glBindTexture(GL_TEXTURE_2D, 0);
 
         for (int r=0 ; !part.count || r<part.count ; r++) {
-            for (int j=0 ; j<fcount && !exitPending(); j++) {
+            for (size_t j=0 ; j<fcount && !exitPending(); j++) {
                 const Animation::Frame& frame(part.frames[j]);
 
                 if (r > 0 && !noTextureCache) {
@@ -523,7 +561,7 @@ bool BootAnimation::movie()
 
         // free the textures for this part
         if (part.count != 1 && !noTextureCache) {
-            for (int j=0 ; j<fcount ; j++) {
+            for (size_t j=0 ; j<fcount ; j++) {
                 const Animation::Frame& frame(part.frames[j]);
                 glDeleteTextures(1, &frame.tid);
             }