/*
** Copyright 2011, The Android Open Source Project
**
** Licensed under the Apache License, Version 2.0 (the "License");
** you may not use this file except in compliance with the License.
** You may obtain a copy of the License at
**
** http://www.apache.org/licenses/LICENSE-2.0
**
** Unless required by applicable law or agreed to in writing, software
** distributed under the License is distributed on an "AS IS" BASIS,
** WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
** See the License for the specific language governing permissions and
** limitations under the License.
*/
#include "egl_cache.h"
#include "egl_display.h"
#include "egl_impl.h"
#include "egldefs.h"
#include <fcntl.h>
#include <sys/mman.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <unistd.h>
#ifndef MAX_EGL_CACHE_ENTRY_SIZE
#define MAX_EGL_CACHE_ENTRY_SIZE (16 * 1024);
#endif
#ifndef MAX_EGL_CACHE_SIZE
#define MAX_EGL_CACHE_SIZE (64 * 1024);
#endif
// Cache size limits.
static const size_t maxKeySize = 1024;
static const size_t maxValueSize = MAX_EGL_CACHE_ENTRY_SIZE;
static const size_t maxTotalSize = MAX_EGL_CACHE_SIZE;
// Cache file header
static const char* cacheFileMagic = "EGL$";
static const size_t cacheFileHeaderSize = 8;
// The time in seconds to wait before saving newly inserted cache entries.
static const unsigned int deferredSaveDelay = 4;
// ----------------------------------------------------------------------------
namespace android {
// ----------------------------------------------------------------------------
#define BC_EXT_STR "EGL_ANDROID_blob_cache"
//
// Callback functions passed to EGL.
//
static void setBlob(const void* key, EGLsizeiANDROID keySize,
const void* value, EGLsizeiANDROID valueSize) {
egl_cache_t::get()->setBlob(key, keySize, value, valueSize);
}
static EGLsizeiANDROID getBlob(const void* key, EGLsizeiANDROID keySize,
void* value, EGLsizeiANDROID valueSize) {
return egl_cache_t::get()->getBlob(key, keySize, value, valueSize);
}
//
// egl_cache_t definition
//
egl_cache_t::egl_cache_t() :
mInitialized(false),
mBlobCache(NULL) {
}
egl_cache_t::~egl_cache_t() {
}
egl_cache_t egl_cache_t::sCache;
egl_cache_t* egl_cache_t::get() {
return &sCache;
}
void egl_cache_t::initialize(egl_display_t *display) {
Mutex::Autolock lock(mMutex);
egl_connection_t* const cnx = &gEGLImpl;
if (cnx->dso && cnx->major >= 0 && cnx->minor >= 0) {
const char* exts = display->disp.queryString.extensions;
size_t bcExtLen = strlen(BC_EXT_STR);
size_t extsLen = strlen(exts);
bool equal = !strcmp(BC_EXT_STR, exts);
bool atStart = !strncmp(BC_EXT_STR " ", exts, bcExtLen+1);
bool atEnd = (bcExtLen+1) < extsLen &&
!strcmp(" " BC_EXT_STR, exts + extsLen - (bcExtLen+1));
bool inMiddle = strstr(exts, " " BC_EXT_STR " ");
if (equal || atStart || atEnd || inMiddle) {
PFNEGLSETBLOBCACHEFUNCSANDROIDPROC eglSetBlobCacheFuncsANDROID;
eglSetBlobCacheFuncsANDROID =
reinterpret_cast<PFNEGLSETBLOBCACHEFUNCSANDROIDPROC>(
cnx->egl.eglGetProcAddress(
"eglSetBlobCacheFuncsANDROID"));
if (eglSetBlobCacheFuncsANDROID == NULL) {
ALOGE("EGL_ANDROID_blob_cache advertised, "
"but unable to get eglSetBlobCacheFuncsANDROID");
return;
}
eglSetBlobCacheFuncsANDROID(display->disp.dpy,
android::setBlob, android::getBlob);
EGLint err = cnx->egl.eglGetError();
if (err != EGL_SUCCESS) {
ALOGE("eglSetBlobCacheFuncsANDROID resulted in an error: "
"%#x", err);
}
}
}
mInitialized = true;
}
void egl_cache_t::terminate() {
Mutex::Autolock lock(mMutex);
if (mBlobCache != NULL) {
saveBlobCacheLocked();
mBlobCache = NULL;
}
mInitialized = false;
}
void egl_cache_t::setBlob(const void* key, EGLsizeiANDROID keySize,
const void* value, EGLsizeiANDROID valueSize) {
Mutex::Autolock lock(mMutex);
if (keySize < 0 || valueSize < 0) {
ALOGW("EGL_ANDROID_blob_cache set: negative sizes are not allowed");
return;
}
if (mInitialized) {
sp<BlobCache> bc = getBlobCacheLocked();
bc->set(key, keySize, value, valueSize);
if (!mSavePending) {
class DeferredSaveThread : public Thread {
public:
DeferredSaveThread() : Thread(false) {}
virtual bool threadLoop() {
sleep(deferredSaveDelay);
egl_cache_t* c = egl_cache_t::get();
Mutex::Autolock lock(c->mMutex);
if (c->mInitialized) {
c->saveBlobCacheLocked();
}
c->mSavePending = false;
return false;
}
};
// The thread will hold a strong ref to itself until it has finished
// running, so there's no need to keep a ref around.
sp<Thread> deferredSaveThread(new DeferredSaveThread());
mSavePending = true;
deferredSaveThread->run();
}
}
}
EGLsizeiANDROID egl_cache_t::getBlob(const void* key, EGLsizeiANDROID keySize,
void* value, EGLsizeiANDROID valueSize) {
Mutex::Autolock lock(mMutex);
if (keySize < 0 || valueSize < 0) {
ALOGW("EGL_ANDROID_blob_cache set: negative sizes are not allowed");
return 0;
}
if (mInitialized) {
sp<BlobCache> bc = getBlobCacheLocked();
return bc->get(key, keySize, value, valueSize);
}
return 0;
}
void egl_cache_t::setCacheFilename(const char* filename) {
Mutex::Autolock lock(mMutex);
mFilename = filename;
}
sp<BlobCache> egl_cache_t::getBlobCacheLocked() {
if (mBlobCache == NULL) {
mBlobCache = new BlobCache(maxKeySize, maxValueSize, maxTotalSize);
loadBlobCacheLocked();
}
return mBlobCache;
}
static uint32_t crc32c(const uint8_t* buf, size_t len) {
const uint32_t polyBits = 0x82F63B78;
uint32_t r = 0;
for (size_t i = 0; i < len; i++) {
r ^= buf[i];
for (int j = 0; j < 8; j++) {
if (r & 1) {
r = (r >> 1) ^ polyBits;
} else {
r >>= 1;
}
}
}
return r;
}
void egl_cache_t::saveBlobCacheLocked() {
if (mFilename.length() > 0) {
size_t cacheSize = mBlobCache->getFlattenedSize();
size_t headerSize = cacheFileHeaderSize;
const char* fname = mFilename.string();
// Try to create the file with no permissions so we can write it
// without anyone trying to read it.
int fd = open(fname, O_CREAT | O_EXCL | O_RDWR, 0);
if (fd == -1) {
if (errno == EEXIST) {
// The file exists, delete it and try again.
if (unlink(fname) == -1) {
// No point in retrying if the unlink failed.
ALOGE("error unlinking cache file %s: %s (%d)", fname,
strerror(errno), errno);
return;
}
// Retry now that we've unlinked the file.
fd = open(fname, O_CREAT | O_EXCL | O_RDWR, 0);
}
if (fd == -1) {
ALOGE("error creating cache file %s: %s (%d)", fname,
strerror(errno), errno);
return;
}
}
size_t fileSize = headerSize + cacheSize;
if (ftruncate(fd, fileSize) == -1) {
ALOGE("error setting cache file size: %s (%d)", strerror(errno),
errno);
close(fd);
unlink(fname);
return;
}
uint8_t* buf = reinterpret_cast<uint8_t*>(mmap(NULL, fileSize,
PROT_WRITE, MAP_SHARED, fd, 0));
if (buf == MAP_FAILED) {
ALOGE("error mmaping cache file: %s (%d)", strerror(errno),
errno);
close(fd);
unlink(fname);
return;
}
status_t err = mBlobCache->flatten(buf + headerSize, cacheSize, NULL,
0);
if (err != OK) {
ALOGE("error writing cache contents: %s (%d)", strerror(-err),
-err);
munmap(buf, fileSize);
close(fd);
unlink(fname);
return;
}
// Write the file magic and CRC
memcpy(buf, cacheFileMagic, 4);
uint32_t* crc = reinterpret_cast<uint32_t*>(buf + 4);
*crc = crc32c(buf + headerSize, cacheSize);
munmap(buf, fileSize);
fchmod(fd, S_IRUSR);
close(fd);
}
}
void egl_cache_t::loadBlobCacheLocked() {
if (mFilename.length() > 0) {
size_t headerSize = cacheFileHeaderSize;
int fd = open(mFilename.string(), O_RDONLY, 0);
if (fd == -1) {
if (errno != ENOENT) {
ALOGE("error opening cache file %s: %s (%d)", mFilename.string(),
strerror(errno), errno);
}
return;
}
struct stat statBuf;
if (fstat(fd, &statBuf) == -1) {
ALOGE("error stat'ing cache file: %s (%d)", strerror(errno), errno);
close(fd);
return;
}
// Sanity check the size before trying to mmap it.
size_t fileSize = statBuf.st_size;
if (fileSize > maxTotalSize * 2) {
ALOGE("cache file is too large: %#llx", statBuf.st_size);
close(fd);
return;
}
uint8_t* buf = reinterpret_cast<uint8_t*>(mmap(NULL, fileSize,
PROT_READ, MAP_PRIVATE, fd, 0));
if (buf == MAP_FAILED) {
ALOGE("error mmaping cache file: %s (%d)", strerror(errno),
errno);
close(fd);
return;
}
// Check the file magic and CRC
size_t cacheSize = fileSize - headerSize;
if (memcmp(buf, cacheFileMagic, 4) != 0) {
ALOGE("cache file has bad mojo");
close(fd);
return;
}
uint32_t* crc = reinterpret_cast<uint32_t*>(buf + 4);
if (crc32c(buf + headerSize, cacheSize) != *crc) {
ALOGE("cache file failed CRC check");
close(fd);
return;
}
status_t err = mBlobCache->unflatten(buf + headerSize, cacheSize, NULL,
0);
if (err != OK) {
ALOGE("error reading cache contents: %s (%d)", strerror(-err),
-err);
munmap(buf, fileSize);
close(fd);
return;
}
munmap(buf, fileSize);
close(fd);
}
}
// ----------------------------------------------------------------------------
}; // namespace android
// ----------------------------------------------------------------------------