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authorAnton Samokhvalov <pg83@yandex.ru>2022-02-10 16:45:15 +0300
committerDaniil Cherednik <dcherednik@yandex-team.ru>2022-02-10 16:45:15 +0300
commit72cb13b4aff9bc9cf22e49251bc8fd143f82538f (patch)
treeda2c34829458c7d4e74bdfbdf85dff449e9e7fb8 /contrib/libs/brotli/dec/bit_reader.h
parent778e51ba091dc39e7b7fcab2b9cf4dbedfb6f2b5 (diff)
downloadydb-72cb13b4aff9bc9cf22e49251bc8fd143f82538f.tar.gz
Restoring authorship annotation for Anton Samokhvalov <pg83@yandex.ru>. Commit 1 of 2.
Diffstat (limited to 'contrib/libs/brotli/dec/bit_reader.h')
-rw-r--r--contrib/libs/brotli/dec/bit_reader.h232
1 files changed, 116 insertions, 116 deletions
diff --git a/contrib/libs/brotli/dec/bit_reader.h b/contrib/libs/brotli/dec/bit_reader.h
index c06e91419f..732072bfdd 100644
--- a/contrib/libs/brotli/dec/bit_reader.h
+++ b/contrib/libs/brotli/dec/bit_reader.h
@@ -1,25 +1,25 @@
-/* Copyright 2013 Google Inc. All Rights Reserved.
-
+/* Copyright 2013 Google Inc. All Rights Reserved.
+
Distributed under MIT license.
See file LICENSE for detail or copy at https://opensource.org/licenses/MIT
-*/
-
-/* Bit reading helpers */
-
-#ifndef BROTLI_DEC_BIT_READER_H_
-#define BROTLI_DEC_BIT_READER_H_
-
+*/
+
+/* Bit reading helpers */
+
+#ifndef BROTLI_DEC_BIT_READER_H_
+#define BROTLI_DEC_BIT_READER_H_
+
#include <string.h> /* memcpy */
-
+
#include "../common/platform.h"
#include <brotli/types.h>
-
-#if defined(__cplusplus) || defined(c_plusplus)
-extern "C" {
-#endif
-
+
+#if defined(__cplusplus) || defined(c_plusplus)
+extern "C" {
+#endif
+
#define BROTLI_SHORT_FILL_BIT_WINDOW_READ (sizeof(brotli_reg_t) >> 1)
-
+
static const uint32_t kBitMask[33] = { 0x00000000,
0x00000001, 0x00000003, 0x00000007, 0x0000000F,
0x0000001F, 0x0000003F, 0x0000007F, 0x000000FF,
@@ -30,7 +30,7 @@ static const uint32_t kBitMask[33] = { 0x00000000,
0x01FFFFFF, 0x03FFFFFF, 0x07FFFFFF, 0x0FFFFFFF,
0x1FFFFFFF, 0x3FFFFFFF, 0x7FFFFFFF, 0xFFFFFFFF
};
-
+
static BROTLI_INLINE uint32_t BitMask(uint32_t n) {
if (BROTLI_IS_CONSTANT(n) || BROTLI_HAS_UBFX) {
/* Masking with this expression turns to a single
@@ -41,20 +41,20 @@ static BROTLI_INLINE uint32_t BitMask(uint32_t n) {
}
}
-typedef struct {
+typedef struct {
brotli_reg_t val_; /* pre-fetched bits */
uint32_t bit_pos_; /* current bit-reading position in val_ */
const uint8_t* next_in; /* the byte we're reading from */
size_t avail_in;
-} BrotliBitReader;
-
+} BrotliBitReader;
+
typedef struct {
brotli_reg_t val_;
uint32_t bit_pos_;
const uint8_t* next_in;
size_t avail_in;
} BrotliBitReaderState;
-
+
/* Initializes the BrotliBitReader fields. */
BROTLI_INTERNAL void BrotliInitBitReader(BrotliBitReader* const br);
@@ -64,7 +64,7 @@ BROTLI_INTERNAL void BrotliInitBitReader(BrotliBitReader* const br);
For BROTLI_ALIGNED_READ this function also prepares bit reader for aligned
reading. */
BROTLI_INTERNAL BROTLI_BOOL BrotliWarmupBitReader(BrotliBitReader* const br);
-
+
static BROTLI_INLINE void BrotliBitReaderSaveState(
BrotliBitReader* const from, BrotliBitReaderState* to) {
to->val_ = from->val_;
@@ -72,7 +72,7 @@ static BROTLI_INLINE void BrotliBitReaderSaveState(
to->next_in = from->next_in;
to->avail_in = from->avail_in;
}
-
+
static BROTLI_INLINE void BrotliBitReaderRestoreState(
BrotliBitReader* const to, BrotliBitReaderState* from) {
to->val_ = from->val_;
@@ -80,15 +80,15 @@ static BROTLI_INLINE void BrotliBitReaderRestoreState(
to->next_in = from->next_in;
to->avail_in = from->avail_in;
}
-
+
static BROTLI_INLINE uint32_t BrotliGetAvailableBits(
const BrotliBitReader* br) {
return (BROTLI_64_BITS ? 64 : 32) - br->bit_pos_;
-}
-
-/* Returns amount of unread bytes the bit reader still has buffered from the
- BrotliInput, including whole bytes in br->val_. */
-static BROTLI_INLINE size_t BrotliGetRemainingBytes(BrotliBitReader* br) {
+}
+
+/* Returns amount of unread bytes the bit reader still has buffered from the
+ BrotliInput, including whole bytes in br->val_. */
+static BROTLI_INLINE size_t BrotliGetRemainingBytes(BrotliBitReader* br) {
return br->avail_in + (BrotliGetAvailableBits(br) >> 3);
}
@@ -100,59 +100,59 @@ static BROTLI_INLINE BROTLI_BOOL BrotliCheckInputAmount(
}
/* Guarantees that there are at least |n_bits| + 1 bits in accumulator.
- Precondition: accumulator contains at least 1 bit.
+ Precondition: accumulator contains at least 1 bit.
|n_bits| should be in the range [1..24] for regular build. For portable
non-64-bit little-endian build only 16 bits are safe to request. */
-static BROTLI_INLINE void BrotliFillBitWindow(
+static BROTLI_INLINE void BrotliFillBitWindow(
BrotliBitReader* const br, uint32_t n_bits) {
#if (BROTLI_64_BITS)
if (!BROTLI_ALIGNED_READ && BROTLI_IS_CONSTANT(n_bits) && (n_bits <= 8)) {
- if (br->bit_pos_ >= 56) {
- br->val_ >>= 56;
- br->bit_pos_ ^= 56; /* here same as -= 56 because of the if condition */
+ if (br->bit_pos_ >= 56) {
+ br->val_ >>= 56;
+ br->bit_pos_ ^= 56; /* here same as -= 56 because of the if condition */
br->val_ |= BROTLI_UNALIGNED_LOAD64LE(br->next_in) << 8;
- br->avail_in -= 7;
- br->next_in += 7;
- }
+ br->avail_in -= 7;
+ br->next_in += 7;
+ }
} else if (
!BROTLI_ALIGNED_READ && BROTLI_IS_CONSTANT(n_bits) && (n_bits <= 16)) {
- if (br->bit_pos_ >= 48) {
- br->val_ >>= 48;
- br->bit_pos_ ^= 48; /* here same as -= 48 because of the if condition */
+ if (br->bit_pos_ >= 48) {
+ br->val_ >>= 48;
+ br->bit_pos_ ^= 48; /* here same as -= 48 because of the if condition */
br->val_ |= BROTLI_UNALIGNED_LOAD64LE(br->next_in) << 16;
- br->avail_in -= 6;
- br->next_in += 6;
- }
- } else {
- if (br->bit_pos_ >= 32) {
- br->val_ >>= 32;
- br->bit_pos_ ^= 32; /* here same as -= 32 because of the if condition */
+ br->avail_in -= 6;
+ br->next_in += 6;
+ }
+ } else {
+ if (br->bit_pos_ >= 32) {
+ br->val_ >>= 32;
+ br->bit_pos_ ^= 32; /* here same as -= 32 because of the if condition */
br->val_ |= ((uint64_t)BROTLI_UNALIGNED_LOAD32LE(br->next_in)) << 32;
br->avail_in -= BROTLI_SHORT_FILL_BIT_WINDOW_READ;
br->next_in += BROTLI_SHORT_FILL_BIT_WINDOW_READ;
- }
- }
+ }
+ }
#else
if (!BROTLI_ALIGNED_READ && BROTLI_IS_CONSTANT(n_bits) && (n_bits <= 8)) {
- if (br->bit_pos_ >= 24) {
- br->val_ >>= 24;
- br->bit_pos_ ^= 24; /* here same as -= 24 because of the if condition */
+ if (br->bit_pos_ >= 24) {
+ br->val_ >>= 24;
+ br->bit_pos_ ^= 24; /* here same as -= 24 because of the if condition */
br->val_ |= BROTLI_UNALIGNED_LOAD32LE(br->next_in) << 8;
- br->avail_in -= 3;
- br->next_in += 3;
- }
- } else {
- if (br->bit_pos_ >= 16) {
- br->val_ >>= 16;
- br->bit_pos_ ^= 16; /* here same as -= 16 because of the if condition */
+ br->avail_in -= 3;
+ br->next_in += 3;
+ }
+ } else {
+ if (br->bit_pos_ >= 16) {
+ br->val_ >>= 16;
+ br->bit_pos_ ^= 16; /* here same as -= 16 because of the if condition */
br->val_ |= ((uint32_t)BROTLI_UNALIGNED_LOAD16LE(br->next_in)) << 16;
br->avail_in -= BROTLI_SHORT_FILL_BIT_WINDOW_READ;
br->next_in += BROTLI_SHORT_FILL_BIT_WINDOW_READ;
- }
- }
-#endif
-}
-
+ }
+ }
+#endif
+}
+
/* Mostly like BrotliFillBitWindow, but guarantees only 16 bits and reads no
more than BROTLI_SHORT_FILL_BIT_WINDOW_READ bytes of input. */
static BROTLI_INLINE void BrotliFillBitWindow16(BrotliBitReader* const br) {
@@ -165,25 +165,25 @@ static BROTLI_INLINE BROTLI_BOOL BrotliPullByte(BrotliBitReader* const br) {
if (br->avail_in == 0) {
return BROTLI_FALSE;
}
- br->val_ >>= 8;
+ br->val_ >>= 8;
#if (BROTLI_64_BITS)
br->val_ |= ((uint64_t)*br->next_in) << 56;
-#else
+#else
br->val_ |= ((uint32_t)*br->next_in) << 24;
-#endif
- br->bit_pos_ -= 8;
- --br->avail_in;
- ++br->next_in;
+#endif
+ br->bit_pos_ -= 8;
+ --br->avail_in;
+ ++br->next_in;
return BROTLI_TRUE;
-}
-
+}
+
/* Returns currently available bits.
The number of valid bits could be calculated by BrotliGetAvailableBits. */
static BROTLI_INLINE brotli_reg_t BrotliGetBitsUnmasked(
BrotliBitReader* const br) {
return br->val_ >> br->bit_pos_;
-}
-
+}
+
/* Like BrotliGetBits, but does not mask the result.
The result contains at least 16 valid bits. */
static BROTLI_INLINE uint32_t BrotliGet16BitsUnmasked(
@@ -194,12 +194,12 @@ static BROTLI_INLINE uint32_t BrotliGet16BitsUnmasked(
/* Returns the specified number of bits from |br| without advancing bit
position. */
-static BROTLI_INLINE uint32_t BrotliGetBits(
+static BROTLI_INLINE uint32_t BrotliGetBits(
BrotliBitReader* const br, uint32_t n_bits) {
- BrotliFillBitWindow(br, n_bits);
+ BrotliFillBitWindow(br, n_bits);
return (uint32_t)BrotliGetBitsUnmasked(br) & BitMask(n_bits);
-}
-
+}
+
/* Tries to peek the specified amount of bits. Returns BROTLI_FALSE, if there
is not enough input. */
static BROTLI_INLINE BROTLI_BOOL BrotliSafeGetBits(
@@ -214,11 +214,11 @@ static BROTLI_INLINE BROTLI_BOOL BrotliSafeGetBits(
}
/* Advances the bit pos by |n_bits|. */
-static BROTLI_INLINE void BrotliDropBits(
+static BROTLI_INLINE void BrotliDropBits(
BrotliBitReader* const br, uint32_t n_bits) {
br->bit_pos_ += n_bits;
-}
-
+}
+
static BROTLI_INLINE void BrotliBitReaderUnload(BrotliBitReader* br) {
uint32_t unused_bytes = BrotliGetAvailableBits(br) >> 3;
uint32_t unused_bits = unused_bytes << 3;
@@ -234,17 +234,17 @@ static BROTLI_INLINE void BrotliBitReaderUnload(BrotliBitReader* br) {
/* Reads the specified number of bits from |br| and advances the bit pos.
Precondition: accumulator MUST contain at least |n_bits|. */
-static BROTLI_INLINE void BrotliTakeBits(
+static BROTLI_INLINE void BrotliTakeBits(
BrotliBitReader* const br, uint32_t n_bits, uint32_t* val) {
*val = (uint32_t)BrotliGetBitsUnmasked(br) & BitMask(n_bits);
BROTLI_LOG(("[BrotliReadBits] %d %d %d val: %6x\n",
(int)br->avail_in, (int)br->bit_pos_, (int)n_bits, (int)*val));
BrotliDropBits(br, n_bits);
-}
-
+}
+
/* Reads the specified number of bits from |br| and advances the bit pos.
- Assumes that there is enough input to perform BrotliFillBitWindow. */
-static BROTLI_INLINE uint32_t BrotliReadBits(
+ Assumes that there is enough input to perform BrotliFillBitWindow. */
+static BROTLI_INLINE uint32_t BrotliReadBits(
BrotliBitReader* const br, uint32_t n_bits) {
if (BROTLI_64_BITS || (n_bits <= 16)) {
uint32_t val;
@@ -260,8 +260,8 @@ static BROTLI_INLINE uint32_t BrotliReadBits(
BrotliTakeBits(br, n_bits - 16, &high_val);
return low_val | (high_val << 16);
}
-}
-
+}
+
/* Tries to read the specified amount of bits. Returns BROTLI_FALSE, if there
is not enough input. |n_bits| MUST be positive. */
static BROTLI_INLINE BROTLI_BOOL BrotliSafeReadBits(
@@ -269,41 +269,41 @@ static BROTLI_INLINE BROTLI_BOOL BrotliSafeReadBits(
while (BrotliGetAvailableBits(br) < n_bits) {
if (!BrotliPullByte(br)) {
return BROTLI_FALSE;
- }
- }
- BrotliTakeBits(br, n_bits, val);
+ }
+ }
+ BrotliTakeBits(br, n_bits, val);
return BROTLI_TRUE;
-}
-
-/* Advances the bit reader position to the next byte boundary and verifies
- that any skipped bits are set to zero. */
+}
+
+/* Advances the bit reader position to the next byte boundary and verifies
+ that any skipped bits are set to zero. */
static BROTLI_INLINE BROTLI_BOOL BrotliJumpToByteBoundary(BrotliBitReader* br) {
uint32_t pad_bits_count = BrotliGetAvailableBits(br) & 0x7;
- uint32_t pad_bits = 0;
- if (pad_bits_count != 0) {
- BrotliTakeBits(br, pad_bits_count, &pad_bits);
- }
+ uint32_t pad_bits = 0;
+ if (pad_bits_count != 0) {
+ BrotliTakeBits(br, pad_bits_count, &pad_bits);
+ }
return TO_BROTLI_BOOL(pad_bits == 0);
-}
-
-/* Copies remaining input bytes stored in the bit reader to the output. Value
+}
+
+/* Copies remaining input bytes stored in the bit reader to the output. Value
|num| may not be larger than BrotliGetRemainingBytes. The bit reader must be
- warmed up again after this. */
-static BROTLI_INLINE void BrotliCopyBytes(uint8_t* dest,
- BrotliBitReader* br, size_t num) {
+ warmed up again after this. */
+static BROTLI_INLINE void BrotliCopyBytes(uint8_t* dest,
+ BrotliBitReader* br, size_t num) {
while (BrotliGetAvailableBits(br) >= 8 && num > 0) {
*dest = (uint8_t)BrotliGetBitsUnmasked(br);
BrotliDropBits(br, 8);
- ++dest;
- --num;
- }
- memcpy(dest, br->next_in, num);
+ ++dest;
+ --num;
+ }
+ memcpy(dest, br->next_in, num);
br->avail_in -= num;
- br->next_in += num;
-}
-
-#if defined(__cplusplus) || defined(c_plusplus)
+ br->next_in += num;
+}
+
+#if defined(__cplusplus) || defined(c_plusplus)
} /* extern "C" */
-#endif
-
-#endif /* BROTLI_DEC_BIT_READER_H_ */
+#endif
+
+#endif /* BROTLI_DEC_BIT_READER_H_ */