libgui: Add generation numbers to BufferQueue
This change allows producers to set a generation number on a
BufferQueue. This number will be embedded in any new GraphicBuffers
created in that BufferQueue, and attempts to attach buffers which have
a different generation number will fail.
It also plumbs the setGenerationNumber method through Surface, with the
additional effect that any buffers attached to the Surface after
setting a new generation number will automatically be updated with the
new number (as opposed to failing, as would happen on through IGBP).
Bug: 20923096
Change-Id: I32bf726b035f99c3e5834beaf76afb9f01adcbc2
diff --git a/libs/ui/GraphicBuffer.cpp b/libs/ui/GraphicBuffer.cpp
index 6a42a22..e55db30 100644
--- a/libs/ui/GraphicBuffer.cpp
+++ b/libs/ui/GraphicBuffer.cpp
@@ -278,7 +278,7 @@
}
size_t GraphicBuffer::getFlattenedSize() const {
- return static_cast<size_t>(10 + (handle ? handle->numInts : 0)) * sizeof(int);
+ return static_cast<size_t>(11 + (handle ? handle->numInts : 0)) * sizeof(int);
}
size_t GraphicBuffer::getFdCount() const {
@@ -301,15 +301,16 @@
buf[5] = usage;
buf[6] = static_cast<int32_t>(mId >> 32);
buf[7] = static_cast<int32_t>(mId & 0xFFFFFFFFull);
- buf[8] = 0;
+ buf[8] = static_cast<int32_t>(mGenerationNumber);
buf[9] = 0;
+ buf[10] = 0;
if (handle) {
- buf[8] = handle->numFds;
- buf[9] = handle->numInts;
+ buf[9] = handle->numFds;
+ buf[10] = handle->numInts;
memcpy(fds, handle->data,
static_cast<size_t>(handle->numFds) * sizeof(int));
- memcpy(&buf[10], handle->data + handle->numFds,
+ memcpy(&buf[11], handle->data + handle->numFds,
static_cast<size_t>(handle->numInts) * sizeof(int));
}
@@ -325,20 +326,20 @@
status_t GraphicBuffer::unflatten(
void const*& buffer, size_t& size, int const*& fds, size_t& count) {
- if (size < 8*sizeof(int)) return NO_MEMORY;
+ if (size < 11 * sizeof(int)) return NO_MEMORY;
int const* buf = static_cast<int const*>(buffer);
if (buf[0] != 'GBFR') return BAD_TYPE;
- const size_t numFds = static_cast<size_t>(buf[8]);
- const size_t numInts = static_cast<size_t>(buf[9]);
+ const size_t numFds = static_cast<size_t>(buf[9]);
+ const size_t numInts = static_cast<size_t>(buf[10]);
// Limit the maxNumber to be relatively small. The number of fds or ints
// should not come close to this number, and the number itself was simply
// chosen to be high enough to not cause issues and low enough to prevent
// overflow problems.
const size_t maxNumber = 4096;
- if (numFds >= maxNumber || numInts >= (maxNumber - 10)) {
+ if (numFds >= maxNumber || numInts >= (maxNumber - 11)) {
width = height = stride = format = usage = 0;
handle = NULL;
ALOGE("unflatten: numFds or numInts is too large: %zd, %zd",
@@ -346,7 +347,7 @@
return BAD_VALUE;
}
- const size_t sizeNeeded = (10 + numInts) * sizeof(int);
+ const size_t sizeNeeded = (11 + numInts) * sizeof(int);
if (size < sizeNeeded) return NO_MEMORY;
size_t fdCountNeeded = numFds;
@@ -372,7 +373,7 @@
return NO_MEMORY;
}
memcpy(h->data, fds, numFds * sizeof(int));
- memcpy(h->data + numFds, &buf[10], numInts * sizeof(int));
+ memcpy(h->data + numFds, &buf[11], numInts * sizeof(int));
handle = h;
} else {
width = height = stride = format = usage = 0;
@@ -382,6 +383,8 @@
mId = static_cast<uint64_t>(buf[6]) << 32;
mId |= static_cast<uint32_t>(buf[7]);
+ mGenerationNumber = static_cast<uint32_t>(buf[8]);
+
mOwner = ownHandle;
if (handle != 0) {