1 /* 2 * Copyright (C) 2007 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 #include <cutils/native_handle.h> 18 19 #include <errno.h> 20 #include <stdint.h> 21 #include <stdlib.h> 22 #include <string.h> 23 #include <unistd.h> 24 25 static const int kMaxNativeFds = 1024; 26 static const int kMaxNativeInts = 1024; 27 28 native_handle_t* native_handle_init(char* storage, int numFds, int numInts) { 29 if ((uintptr_t) storage % alignof(native_handle_t)) { 30 errno = EINVAL; 31 return NULL; 32 } 33 34 native_handle_t* handle = (native_handle_t*) storage; 35 handle->version = sizeof(native_handle_t); 36 handle->numFds = numFds; 37 handle->numInts = numInts; 38 return handle; 39 } 40 41 native_handle_t* native_handle_create(int numFds, int numInts) { 42 if (numFds < 0 || numInts < 0 || numFds > kMaxNativeFds || numInts > kMaxNativeInts) { 43 errno = EINVAL; 44 return NULL; 45 } 46 47 size_t mallocSize = sizeof(native_handle_t) + (sizeof(int) * (numFds + numInts)); 48 native_handle_t* h = static_cast<native_handle_t*>(malloc(mallocSize)); 49 if (h) { 50 h->version = sizeof(native_handle_t); 51 h->numFds = numFds; 52 h->numInts = numInts; 53 } 54 return h; 55 } 56 57 native_handle_t* native_handle_clone(const native_handle_t* handle) { 58 native_handle_t* clone = native_handle_create(handle->numFds, handle->numInts); 59 if (clone == NULL) return NULL; 60 61 for (int i = 0; i < handle->numFds; i++) { 62 clone->data[i] = dup(handle->data[i]); 63 if (clone->data[i] == -1) { 64 clone->numFds = i; 65 native_handle_close(clone); 66 native_handle_delete(clone); 67 return NULL; 68 } 69 } 70 71 memcpy(&clone->data[handle->numFds], &handle->data[handle->numFds], 72 sizeof(int) * handle->numInts); 73 74 return clone; 75 } 76 77 int native_handle_delete(native_handle_t* h) { 78 if (h) { 79 if (h->version != sizeof(native_handle_t)) return -EINVAL; 80 free(h); 81 } 82 return 0; 83 } 84 85 int native_handle_close(const native_handle_t* h) { 86 if (h->version != sizeof(native_handle_t)) return -EINVAL; 87 88 int saved_errno = errno; 89 const int numFds = h->numFds; 90 for (int i = 0; i < numFds; ++i) { 91 close(h->data[i]); 92 } 93 errno = saved_errno; 94 return 0; 95 } 96