status_t CursorWindow::create(const String8& name, size_t size, CursorWindow** outCursorWindow) {
String8 ashmemName("CursorWindow: ");
ashmemName.append(name);
status_t result;
int ashmemFd = ashmem_create_region(ashmemName.string(), size);
if (ashmemFd < 0) {
ALOG(LOG_ERROR,LOG_TAG,"CursorWindow::create, ashmem_create_region return errno = %d",errno);
result = -errno;
} else {
result = ashmem_set_prot_region(ashmemFd, PROT_READ | PROT_WRITE);
if (result >= 0) {
void* data = ::mmap(NULL, size, PROT_READ | PROT_WRITE, MAP_SHARED, ashmemFd, 0);
if (data == MAP_FAILED) {
ALOG(LOG_ERROR,LOG_TAG,"CursorWindow::create, mmap return errno = %d",errno);
result = -errno;
} else {
result = ashmem_set_prot_region(ashmemFd, PROT_READ);
if (result >= 0) {
CursorWindow* window = new CursorWindow(name, ashmemFd,
data, size, false /*readOnly*/);
result = window->clear();
if (!result) {
LOG_WINDOW("Created new CursorWindow: freeOffset=%d, "
"numRows=%d, numColumns=%d, mSize=%d, mData=%p",
window->mHeader->freeOffset,
window->mHeader->numRows,
window->mHeader->numColumns,
window->mSize, window->mData);
*outCursorWindow = window;
return OK;
}
ALOG(LOG_ERROR,LOG_TAG,"CursorWindow::create, window->clear return errno = %d",errno);
delete window;
} else {
ALOG(LOG_ERROR,LOG_TAG,"CursorWindow::create, ashmeme_set_prot_region return errno = %d",errno);
}
}
::munmap(data, size);
}
::close(ashmemFd);
}
*outCursorWindow = NULL;
return result;
}
status_t InputChannel::openInputChannelPair(const String8& name,
sp<InputChannel>& outServerChannel, sp<InputChannel>& outClientChannel) {
status_t result;
String8 ashmemName("InputChannel ");
ashmemName.append(name);
int serverAshmemFd = ashmem_create_region(ashmemName.string(), DEFAULT_MESSAGE_BUFFER_SIZE);
if (serverAshmemFd < 0) {
result = -errno;
ALOGE("channel '%s' ~ Could not create shared memory region. errno=%d",
name.string(), errno);
} else {
result = ashmem_set_prot_region(serverAshmemFd, PROT_READ | PROT_WRITE);
if (result < 0) {
ALOGE("channel '%s' ~ Error %d trying to set protection of ashmem fd %d.",
name.string(), result, serverAshmemFd);
} else {
// Dup the file descriptor because the server and client input channel objects that
// are returned may have different lifetimes but they share the same shared memory region.
int clientAshmemFd;
clientAshmemFd = dup(serverAshmemFd);
if (clientAshmemFd < 0) {
result = -errno;
ALOGE("channel '%s' ~ Could not dup() shared memory region fd. errno=%d",
name.string(), errno);
} else {
int forward[2];
if (pipe(forward)) {
result = -errno;
ALOGE("channel '%s' ~ Could not create forward pipe. errno=%d",
name.string(), errno);
} else {
int reverse[2];
if (pipe(reverse)) {
result = -errno;
ALOGE("channel '%s' ~ Could not create reverse pipe. errno=%d",
name.string(), errno);
} else {
String8 serverChannelName = name;
serverChannelName.append(" (server)");
outServerChannel = new InputChannel(serverChannelName,
serverAshmemFd, reverse[0], forward[1]);
String8 clientChannelName = name;
clientChannelName.append(" (client)");
outClientChannel = new InputChannel(clientChannelName,
clientAshmemFd, forward[0], reverse[1]);
return OK;
}
::close(forward[0]);
::close(forward[1]);
}
::close(clientAshmemFd);
}
}
::close(serverAshmemFd);
}
outServerChannel.clear();
outClientChannel.clear();
return result;
}
