| /* |
| * This file is part of FFmpeg. |
| * |
| * FFmpeg is free software; you can redistribute it and/or |
| * modify it under the terms of the GNU Lesser General Public |
| * License as published by the Free Software Foundation; either |
| * version 2.1 of the License, or (at your option) any later version. |
| * |
| * FFmpeg is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| * Lesser General Public License for more details. |
| * |
| * You should have received a copy of the GNU Lesser General Public |
| * License along with FFmpeg; if not, write to the Free Software |
| * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
| */ |
| |
| /** |
| * @file |
| * leb128 handling implementations |
| */ |
| |
| #ifndef AVCODEC_LEB_H |
| #define AVCODEC_LEB_H |
| |
| #include "get_bits.h" |
| |
| /** |
| * Read a unsigned integer coded as a variable number of up to eight |
| * little-endian bytes, where the MSB in a byte signals another byte |
| * must be read. |
| * All coded bits are read, but values > UINT_MAX are truncated. |
| */ |
| static inline unsigned get_leb(GetBitContext *s) { |
| int more, i = 0; |
| unsigned leb = 0; |
| |
| do { |
| int byte = get_bits(s, 8); |
| unsigned bits = byte & 0x7f; |
| more = byte & 0x80; |
| if (i <= 4) |
| leb |= bits << (i * 7); |
| if (++i == 8) |
| break; |
| } while (more); |
| |
| return leb; |
| } |
| |
| /** |
| * Read a unsigned integer coded as a variable number of up to eight |
| * little-endian bytes, where the MSB in a byte signals another byte |
| * must be read. |
| */ |
| static inline int64_t get_leb128(GetBitContext *gb) { |
| int64_t ret = 0; |
| |
| for (int i = 0; i < 8; i++) { |
| int byte = get_bits(gb, 8); |
| ret |= (int64_t)(byte & 0x7f) << (i * 7); |
| if (!(byte & 0x80)) |
| break; |
| } |
| |
| return ret; |
| } |
| |
| #endif /* AVCODEC_LEB_H */ |