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-rw-r--r--media/ffvpx/libavcodec/leb.h70
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diff --git a/media/ffvpx/libavcodec/leb.h b/media/ffvpx/libavcodec/leb.h
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+/*
+ * 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 */