Add support for unique_fds and vectors of file descriptors
Change-Id: Ic61e69d9db438b4686032459c896aed2a482c9a5
Test: Unit tests pass
Bug: 25242023
Signed-off-by: Casey Dahlin <sadmac@google.com>
diff --git a/include/binder/Parcel.h b/include/binder/Parcel.h
index 695d5f1..778f9aa 100644
--- a/include/binder/Parcel.h
+++ b/include/binder/Parcel.h
@@ -19,6 +19,7 @@
#include <vector>
+#include <base/unique_fd.h>
#include <cutils/native_handle.h>
#include <utils/Errors.h>
#include <utils/RefBase.h>
@@ -149,6 +150,17 @@
// will be closed once the parcel is destroyed.
status_t writeDupFileDescriptor(int fd);
+ // Place a file descriptor into the parcel. This will not affect the
+ // semantics of the smart file descriptor. A new descriptor will be
+ // created, and will be closed when the parcel is destroyed.
+ status_t writeUniqueFileDescriptor(
+ const android::base::unique_fd& fd);
+
+ // Place a vector of file desciptors into the parcel. Each descriptor is
+ // dup'd as in writeDupFileDescriptor
+ status_t writeUniqueFileDescriptorVector(
+ const std::vector<android::base::unique_fd>& val);
+
// Writes a blob to the parcel.
// If the blob is small, then it is stored in-place, otherwise it is
// transferred by way of an anonymous shared memory region. Prefer sending
@@ -241,6 +253,15 @@
// in the parcel, which you do not own -- use dup() to get your own copy.
int readFileDescriptor() const;
+ // Retrieve a smart file descriptor from the parcel.
+ status_t readUniqueFileDescriptor(
+ android::base::unique_fd* val) const;
+
+
+ // Retrieve a vector of smart file descriptors from the parcel.
+ status_t readUniqueFileDescriptorVector(
+ std::vector<android::base::unique_fd>* val) const;
+
// Reads a blob from the parcel.
// The caller should call release() on the blob after reading its contents.
status_t readBlob(size_t len, ReadableBlob* outBlob) const;
diff --git a/libs/binder/Android.mk b/libs/binder/Android.mk
index ce29ea6..f06b9ca 100644
--- a/libs/binder/Android.mk
+++ b/libs/binder/Android.mk
@@ -42,7 +42,7 @@
include $(CLEAR_VARS)
LOCAL_MODULE := libbinder
-LOCAL_SHARED_LIBRARIES := liblog libcutils libutils
+LOCAL_SHARED_LIBRARIES := liblog libcutils libutils libbase
LOCAL_CLANG := true
LOCAL_SANITIZE := integer
@@ -57,7 +57,7 @@
include $(CLEAR_VARS)
LOCAL_MODULE := libbinder
-LOCAL_STATIC_LIBRARIES += libutils
+LOCAL_STATIC_LIBRARIES += libutils libbase
LOCAL_SRC_FILES := $(sources)
ifneq ($(TARGET_USES_64_BIT_BINDER),true)
ifneq ($(TARGET_IS_64_BIT),true)
diff --git a/libs/binder/Parcel.cpp b/libs/binder/Parcel.cpp
index c808948..a7d27bd 100644
--- a/libs/binder/Parcel.cpp
+++ b/libs/binder/Parcel.cpp
@@ -82,6 +82,8 @@
namespace android {
+using android::base::unique_fd;
+
static pthread_mutex_t gParcelGlobalAllocSizeLock = PTHREAD_MUTEX_INITIALIZER;
static size_t gParcelGlobalAllocSize = 0;
static size_t gParcelGlobalAllocCount = 0;
@@ -1047,12 +1049,20 @@
return -errno;
}
status_t err = writeFileDescriptor(dupFd, true /*takeOwnership*/);
- if (err) {
+ if (err != OK) {
close(dupFd);
}
return err;
}
+status_t Parcel::writeUniqueFileDescriptor(const unique_fd& fd) {
+ return writeDupFileDescriptor(fd.get());
+}
+
+status_t Parcel::writeUniqueFileDescriptorVector(const std::vector<unique_fd>& val) {
+ return writeTypedVector(val, this, &Parcel::writeUniqueFileDescriptor);
+}
+
status_t Parcel::writeBlob(size_t len, bool mutableCopy, WritableBlob* outBlob)
{
if (len > INT32_MAX) {
@@ -1664,16 +1674,36 @@
int Parcel::readFileDescriptor() const
{
const flat_binder_object* flat = readObject(true);
- if (flat) {
- switch (flat->type) {
- case BINDER_TYPE_FD:
- //ALOGI("Returning file descriptor %ld from parcel %p", flat->handle, this);
- return flat->handle;
- }
+
+ if (flat && flat->type == BINDER_TYPE_FD) {
+ return flat->handle;
}
+
return BAD_TYPE;
}
+status_t Parcel::readUniqueFileDescriptor(unique_fd* val) const
+{
+ int got = readFileDescriptor();
+
+ if (got == BAD_TYPE) {
+ return BAD_TYPE;
+ }
+
+ val->reset(dup(got));
+
+ if (val->get() < 0) {
+ return BAD_VALUE;
+ }
+
+ return OK;
+}
+
+
+status_t Parcel::readUniqueFileDescriptorVector(std::vector<unique_fd>* val) const {
+ return readTypedVector(val, this, &Parcel::readUniqueFileDescriptor);
+}
+
status_t Parcel::readBlob(size_t len, ReadableBlob* outBlob) const
{
int32_t blobType;