Permalink
Switch branches/tags
studio-3.2.1 studio-3.1.2 studio-3.0 studio-2.3 gradle_3.1.2 gradle_3.0.0 gradle_2.3.0 android-wear-p-preview-2 android-wear-o-preview-4 android-wear-o-preview-3 android-wear-n-preview-2 android-wear-n-preview-1 android-wear-8.1.0_r1 android-wear-8.0.0_r1 android-wear-7.1.1_r1 android-wear-5.1.1_r1 android-wear-5.1.0_r1 android-wear-5.0.0_r1 android-vts-9.0_r4 android-vts-8.1_r6 android-vts-8.1_r5 android-vts-8.1_r4 android-vts-8.1_r3 android-vts-8.0_r9 android-vts-8.0_r8 android-vts-8.0_r7 android-vts-8.0_r6 android-vts-8.0_r2 android-vts-8.0_r1 android-sdk-support_r11 android-sdk-adt_r20 android-sdk-adt_r16.0.1 android-sdk-4.4.2_r1.0.1 android-sdk-4.4.2_r1 android-sdk-4.0.3_r1 android-sdk-4.0.3-tools_r1 android-p-preview-5 android-p-preview-4 android-p-preview-3 android-p-preview-2 android-p-preview-1 android-o-preview-4 android-o-preview-3 android-o-preview-2 android-o-preview-1 android-o-mr1-preview-2 android-o-mr1-preview-1 android-o-mr1-iot-release-smart-display-r3 android-o-mr1-iot-release-1.0.5 android-o-mr1-iot-release-1.0.4 android-o-mr1-iot-release-1.0.3 android-o-mr1-iot-release-1.0.2 android-o-mr1-iot-release-1.0.1 android-o-mr1-iot-release-1.0.0 android-o-mr1-iot-preview-8 android-o-mr1-iot-preview-7 android-o-mr1-iot-preview-6 android-o-iot-preview-5 android-n-preview-5 android-n-preview-4 android-n-preview-3 android-n-preview-2 android-n-preview-1 android-n-mr2-preview-2 android-n-mr2-preview-1 android-n-mr1-preview-2 android-n-mr1-preview-1 android-n-iot-release-smart-display android-n-iot-release-smart-display-r2 android-n-iot-release-polk-at1 android-n-iot-release-lg-thinq-wk7 android-n-iot-preview-4 android-n-iot-preview-2 android-m-preview android-m-preview-2 android-m-preview-1 android-l-preview_r2 android-cts-verifier-4.0.3_r1 android-cts-verifier-4.0_r1 android-cts-9.0_r4 android-cts-9.0_r3 android-cts-9.0_r2 android-cts-9.0_r1 android-cts-8.1_r11 android-cts-8.1_r10 android-cts-8.1_r9 android-cts-8.1_r8 android-cts-8.1_r7 android-cts-8.1_r6 android-cts-8.1_r5 android-cts-8.1_r4 android-cts-8.1_r3 android-cts-8.1_r2 android-cts-8.1_r1 android-cts-8.0_r15 android-cts-8.0_r14 android-cts-8.0_r13 android-cts-8.0_r12 android-cts-8.0_r11 android-cts-8.0_r10
Nothing to show
Find file Copy path
Fetching contributors…
Cannot retrieve contributors at this time
165 lines (146 sloc) 4.75 KB
/*
* Copyright (C) 2008 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.
*/
/*
* Functions for interpreting LEB128 (little endian base 128) values
*/
#ifndef LIBDEX_LEB128_H_
#define LIBDEX_LEB128_H_
#include "DexFile.h"
/*
* Reads an unsigned LEB128 value, updating the given pointer to point
* just past the end of the read value. This function tolerates
* non-zero high-order bits in the fifth encoded byte.
*/
DEX_INLINE int readUnsignedLeb128(const u1** pStream) {
const u1* ptr = *pStream;
int result = *(ptr++);
if (result > 0x7f) {
int cur = *(ptr++);
result = (result & 0x7f) | ((cur & 0x7f) << 7);
if (cur > 0x7f) {
cur = *(ptr++);
result |= (cur & 0x7f) << 14;
if (cur > 0x7f) {
cur = *(ptr++);
result |= (cur & 0x7f) << 21;
if (cur > 0x7f) {
/*
* Note: We don't check to see if cur is out of
* range here, meaning we tolerate garbage in the
* high four-order bits.
*/
cur = *(ptr++);
result |= cur << 28;
}
}
}
}
*pStream = ptr;
return result;
}
/*
* Reads a signed LEB128 value, updating the given pointer to point
* just past the end of the read value. This function tolerates
* non-zero high-order bits in the fifth encoded byte.
*/
DEX_INLINE int readSignedLeb128(const u1** pStream) {
const u1* ptr = *pStream;
int result = *(ptr++);
if (result <= 0x7f) {
result = (result << 25) >> 25;
} else {
int cur = *(ptr++);
result = (result & 0x7f) | ((cur & 0x7f) << 7);
if (cur <= 0x7f) {
result = (result << 18) >> 18;
} else {
cur = *(ptr++);
result |= (cur & 0x7f) << 14;
if (cur <= 0x7f) {
result = (result << 11) >> 11;
} else {
cur = *(ptr++);
result |= (cur & 0x7f) << 21;
if (cur <= 0x7f) {
result = (result << 4) >> 4;
} else {
/*
* Note: We don't check to see if cur is out of
* range here, meaning we tolerate garbage in the
* high four-order bits.
*/
cur = *(ptr++);
result |= cur << 28;
}
}
}
}
*pStream = ptr;
return result;
}
/*
* Reads an unsigned LEB128 value, updating the given pointer to point
* just past the end of the read value and also indicating whether the
* value was syntactically valid. The only syntactically *invalid*
* values are ones that are five bytes long where the final byte has
* any but the low-order four bits set. Additionally, if the limit is
* passed as non-NULL and bytes would need to be read past the limit,
* then the read is considered invalid.
*/
int readAndVerifyUnsignedLeb128(const u1** pStream, const u1* limit,
bool* okay);
/*
* Reads a signed LEB128 value, updating the given pointer to point
* just past the end of the read value and also indicating whether the
* value was syntactically valid. The only syntactically *invalid*
* values are ones that are five bytes long where the final byte has
* any but the low-order four bits set. Additionally, if the limit is
* passed as non-NULL and bytes would need to be read past the limit,
* then the read is considered invalid.
*/
int readAndVerifySignedLeb128(const u1** pStream, const u1* limit, bool* okay);
/*
* Writes a 32-bit value in unsigned ULEB128 format.
*
* Returns the updated pointer.
*/
DEX_INLINE u1* writeUnsignedLeb128(u1* ptr, u4 data)
{
while (true) {
u1 out = data & 0x7f;
if (out != data) {
*ptr++ = out | 0x80;
data >>= 7;
} else {
*ptr++ = out;
break;
}
}
return ptr;
}
/*
* Returns the number of bytes needed to encode "val" in ULEB128 form.
*/
DEX_INLINE int unsignedLeb128Size(u4 data)
{
int count = 0;
do {
data >>= 7;
count++;
} while (data != 0);
return count;
}
#endif