diff options
Diffstat (limited to 'debian/vendor-h2o/deps/brotli/enc/command.h')
-rw-r--r-- | debian/vendor-h2o/deps/brotli/enc/command.h | 136 |
1 files changed, 0 insertions, 136 deletions
diff --git a/debian/vendor-h2o/deps/brotli/enc/command.h b/debian/vendor-h2o/deps/brotli/enc/command.h deleted file mode 100644 index afb014b..0000000 --- a/debian/vendor-h2o/deps/brotli/enc/command.h +++ /dev/null @@ -1,136 +0,0 @@ -/* Copyright 2013 Google Inc. All Rights Reserved. - - Distributed under MIT license. - See file LICENSE for detail or copy at https://opensource.org/licenses/MIT -*/ - -// This class models a sequence of literals and a backward reference copy. - -#ifndef BROTLI_ENC_COMMAND_H_ -#define BROTLI_ENC_COMMAND_H_ - -#include "./fast_log.h" -#include "./prefix.h" -#include "./types.h" - -namespace brotli { - -static uint32_t kInsBase[] = { 0, 1, 2, 3, 4, 5, 6, 8, 10, 14, 18, 26, 34, 50, - 66, 98, 130, 194, 322, 578, 1090, 2114, 6210, 22594 }; -static uint32_t kInsExtra[] = { 0, 0, 0, 0, 0, 0, 1, 1, 2, 2, 3, 3, 4, 4, - 5, 5, 6, 7, 8, 9, 10, 12, 14, 24 }; -static uint32_t kCopyBase[] = { 2, 3, 4, 5, 6, 7, 8, 9, 10, 12, 14, 18, 22, 30, - 38, 54, 70, 102, 134, 198, 326, 582, 1094, 2118 }; -static uint32_t kCopyExtra[] = { 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 2, 2, 3, 3, - 4, 4, 5, 5, 6, 7, 8, 9, 10, 24 }; - -static inline uint16_t GetInsertLengthCode(size_t insertlen) { - if (insertlen < 6) { - return static_cast<uint16_t>(insertlen); - } else if (insertlen < 130) { - insertlen -= 2; - uint32_t nbits = Log2FloorNonZero(insertlen) - 1u; - return static_cast<uint16_t>((nbits << 1) + (insertlen >> nbits) + 2); - } else if (insertlen < 2114) { - return static_cast<uint16_t>(Log2FloorNonZero(insertlen - 66) + 10); - } else if (insertlen < 6210) { - return 21u; - } else if (insertlen < 22594) { - return 22u; - } else { - return 23u; - } -} - -static inline uint16_t GetCopyLengthCode(size_t copylen) { - if (copylen < 10) { - return static_cast<uint16_t>(copylen - 2); - } else if (copylen < 134) { - copylen -= 6; - uint32_t nbits = Log2FloorNonZero(copylen) - 1u; - return static_cast<uint16_t>((nbits << 1) + (copylen >> nbits) + 4); - } else if (copylen < 2118) { - return static_cast<uint16_t>(Log2FloorNonZero(copylen - 70) + 12); - } else { - return 23u; - } -} - -static inline uint16_t CombineLengthCodes( - uint16_t inscode, uint16_t copycode, bool use_last_distance) { - uint16_t bits64 = - static_cast<uint16_t>((copycode & 0x7u) | ((inscode & 0x7u) << 3)); - if (use_last_distance && inscode < 8 && copycode < 16) { - return (copycode < 8) ? bits64 : (bits64 | 64); - } else { - // "To convert an insert-and-copy length code to an insert length code and - // a copy length code, the following table can be used" - static const uint16_t cells[9] = { 128u, 192u, 384u, 256u, 320u, 512u, - 448u, 576u, 640u }; - return cells[(copycode >> 3) + 3 * (inscode >> 3)] | bits64; - } -} - -static inline void GetLengthCode(size_t insertlen, size_t copylen, - bool use_last_distance, - uint16_t* code, uint64_t* extra) { - uint16_t inscode = GetInsertLengthCode(insertlen); - uint16_t copycode = GetCopyLengthCode(copylen); - uint64_t insnumextra = kInsExtra[inscode]; - uint64_t numextra = insnumextra + kCopyExtra[copycode]; - uint64_t insextraval = insertlen - kInsBase[inscode]; - uint64_t copyextraval = copylen - kCopyBase[copycode]; - *code = CombineLengthCodes(inscode, copycode, use_last_distance); - *extra = (numextra << 48) | (copyextraval << insnumextra) | insextraval; -} - -struct Command { - // distance_code is e.g. 0 for same-as-last short code, or 16 for offset 1. - Command(size_t insertlen, size_t copylen, size_t copylen_code, - size_t distance_code) - : insert_len_(static_cast<uint32_t>(insertlen)) - , copy_len_(static_cast<uint32_t>(copylen)) { - // The distance prefix and extra bits are stored in this Command as if - // npostfix and ndirect were 0, they are only recomputed later after the - // clustering if needed. - PrefixEncodeCopyDistance(distance_code, 0, 0, &dist_prefix_, &dist_extra_); - GetLengthCode(insertlen, copylen_code, dist_prefix_ == 0, - &cmd_prefix_, &cmd_extra_); - } - - explicit Command(size_t insertlen) - : insert_len_(static_cast<uint32_t>(insertlen)) - , copy_len_(0), dist_extra_(0), dist_prefix_(16) { - GetLengthCode(insertlen, 4, dist_prefix_ == 0, &cmd_prefix_, &cmd_extra_); - } - - uint32_t DistanceCode() const { - if (dist_prefix_ < 16) { - return dist_prefix_; - } - uint32_t nbits = dist_extra_ >> 24; - uint32_t extra = dist_extra_ & 0xffffff; - uint32_t prefix = dist_prefix_ - 12 - 2 * nbits; - return (prefix << nbits) + extra + 12; - } - - uint32_t DistanceContext() const { - uint32_t r = cmd_prefix_ >> 6; - uint32_t c = cmd_prefix_ & 7; - if ((r == 0 || r == 2 || r == 4 || r == 7) && (c <= 2)) { - return c; - } - return 3; - } - - uint32_t insert_len_; - uint32_t copy_len_; - uint64_t cmd_extra_; - uint32_t dist_extra_; - uint16_t cmd_prefix_; - uint16_t dist_prefix_; -}; - -} // namespace brotli - -#endif // BROTLI_ENC_COMMAND_H_ |