/libs/rs/rsStream.cpp

  1
  2/*
  3 * Copyright (C) 2009 The Android Open Source Project
  4 *
  5 * Licensed under the Apache License, Version 2.0 (the "License");
  6 * you may not use this file except in compliance with the License.
  7 * You may obtain a copy of the License at
  8 *
  9 *      http://www.apache.org/licenses/LICENSE-2.0
 10 *
 11 * Unless required by applicable law or agreed to in writing, software
 12 * distributed under the License is distributed on an "AS IS" BASIS,
 13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 14 * See the License for the specific language governing permissions and
 15 * limitations under the License.
 16 */
 17
 18#include "rsContext.h"
 19#include "rsStream.h"
 20
 21using namespace android;
 22using namespace android::renderscript;
 23
 24IStream::IStream(const uint8_t *buf, bool use64) {
 25    mData = buf;
 26    mPos = 0;
 27    mUse64 = use64;
 28}
 29
 30void IStream::loadByteArray(void *dest, size_t numBytes) {
 31    memcpy(dest, mData + mPos, numBytes);
 32    mPos += numBytes;
 33}
 34
 35uint64_t IStream::loadOffset() {
 36    uint64_t tmp;
 37    if (mUse64) {
 38        mPos = (mPos + 7) & (~7);
 39        tmp = reinterpret_cast<const uint64_t *>(&mData[mPos])[0];
 40        mPos += sizeof(uint64_t);
 41        return tmp;
 42    }
 43    return loadU32();
 44}
 45
 46void IStream::loadString(String8 *s) {
 47    uint32_t len = loadU32();
 48    s->setTo((const char *)&mData[mPos], len);
 49    mPos += len;
 50}
 51
 52// Output stream implementation
 53OStream::OStream(uint64_t len, bool use64) {
 54    mData = (uint8_t*)malloc(len);
 55    mLength = len;
 56    mPos = 0;
 57    mUse64 = use64;
 58}
 59
 60OStream::~OStream() {
 61    free(mData);
 62}
 63
 64void OStream::addByteArray(const void *src, size_t numBytes) {
 65    // We need to potentially grow more than once if the number of byes we write is substantial
 66    while (mPos + numBytes >= mLength) {
 67        growSize();
 68    }
 69    memcpy(mData + mPos, src, numBytes);
 70    mPos += numBytes;
 71}
 72
 73void OStream::addOffset(uint64_t v) {
 74    if (mUse64) {
 75        mPos = (mPos + 7) & (~7);
 76        if (mPos + sizeof(v) >= mLength) {
 77            growSize();
 78        }
 79        mData[mPos++] = (uint8_t)(v & 0xff);
 80        mData[mPos++] = (uint8_t)((v >> 8) & 0xff);
 81        mData[mPos++] = (uint8_t)((v >> 16) & 0xff);
 82        mData[mPos++] = (uint8_t)((v >> 24) & 0xff);
 83        mData[mPos++] = (uint8_t)((v >> 32) & 0xff);
 84        mData[mPos++] = (uint8_t)((v >> 40) & 0xff);
 85        mData[mPos++] = (uint8_t)((v >> 48) & 0xff);
 86        mData[mPos++] = (uint8_t)((v >> 56) & 0xff);
 87    } else {
 88        addU32(v);
 89    }
 90}
 91
 92void OStream::addString(String8 *s) {
 93    uint32_t len = s->size();
 94    addU32(len);
 95    if (mPos + len*sizeof(char) >= mLength) {
 96        growSize();
 97    }
 98    char *stringData = reinterpret_cast<char *>(&mData[mPos]);
 99    for (uint32_t i = 0; i < len; i ++) {
100        stringData[i] = s->string()[i];
101    }
102    mPos += len*sizeof(char);
103}
104
105void OStream::growSize() {
106    uint8_t *newData = (uint8_t*)malloc(mLength*2);
107    memcpy(newData, mData, mLength*sizeof(uint8_t));
108    mLength = mLength * 2;
109    free(mData);
110    mData = newData;
111}
112
113