platform_system_core/libcutils/native_handle.c

104 lines
2.6 KiB
C

/*
* Copyright (C) 2007 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.
*/
#define LOG_TAG "NativeHandle"
#include <errno.h>
#include <stdint.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <android/log.h>
#include <cutils/native_handle.h>
static const int kMaxNativeFds = 1024;
static const int kMaxNativeInts = 1024;
native_handle_t* native_handle_init(char* storage, int numFds, int numInts)
{
if ((uintptr_t) storage % alignof(native_handle_t)) {
return NULL;
}
native_handle_t* handle = (native_handle_t*) storage;
handle->version = sizeof(native_handle_t);
handle->numFds = numFds;
handle->numInts = numInts;
return handle;
}
native_handle_t* native_handle_create(int numFds, int numInts)
{
if (numFds < 0 || numInts < 0 || numFds > kMaxNativeFds || numInts > kMaxNativeInts) {
return NULL;
}
size_t mallocSize = sizeof(native_handle_t) + (sizeof(int) * (numFds + numInts));
native_handle_t* h = malloc(mallocSize);
if (h) {
h->version = sizeof(native_handle_t);
h->numFds = numFds;
h->numInts = numInts;
}
return h;
}
native_handle_t* native_handle_clone(const native_handle_t* handle)
{
native_handle_t* clone = native_handle_create(handle->numFds, handle->numInts);
int i;
for (i = 0; i < handle->numFds; i++) {
clone->data[i] = dup(handle->data[i]);
if (clone->data[i] < 0) {
clone->numFds = i;
native_handle_close(clone);
native_handle_delete(clone);
return NULL;
}
}
memcpy(&clone->data[handle->numFds], &handle->data[handle->numFds],
sizeof(int) * handle->numInts);
return clone;
}
int native_handle_delete(native_handle_t* h)
{
if (h) {
if (h->version != sizeof(native_handle_t))
return -EINVAL;
free(h);
}
return 0;
}
int native_handle_close(const native_handle_t* h)
{
if (h->version != sizeof(native_handle_t))
return -EINVAL;
const int numFds = h->numFds;
int i;
for (i=0 ; i<numFds ; i++) {
close(h->data[i]);
}
return 0;
}