--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/mupdf-source/thirdparty/brotli/c/dec/state.h	Mon Sep 15 11:43:07 2025 +0200
@@ -0,0 +1,400 @@
+/* Copyright 2015 Google Inc. All Rights Reserved.
+
+   Distributed under MIT license.
+   See file LICENSE for detail or copy at https://opensource.org/licenses/MIT
+*/
+
+/* Brotli state for partial streaming decoding. */
+
+#ifndef BROTLI_DEC_STATE_H_
+#define BROTLI_DEC_STATE_H_
+
+#include <brotli/decode.h>
+#include <brotli/shared_dictionary.h>
+#include <brotli/types.h>
+
+#include "../common/constants.h"
+#include "../common/dictionary.h"
+#include "../common/platform.h"
+#include "../common/transform.h"
+#include "bit_reader.h"
+#include "huffman.h"
+
+#if defined(__cplusplus) || defined(c_plusplus)
+extern "C" {
+#endif
+
+/* Graphviz diagram that describes state transitions:
+
+digraph States {
+  graph [compound=true]
+  concentrate=true
+  node [shape="box"]
+
+  UNINITED -> {LARGE_WINDOW_BITS -> INITIALIZE}
+  subgraph cluster_metablock_workflow {
+    style="rounded"
+    label=< <B>METABLOCK CYCLE</B> >
+    METABLOCK_BEGIN -> METABLOCK_HEADER
+    METABLOCK_HEADER:sw -> METADATA
+    METABLOCK_HEADER:s -> UNCOMPRESSED
+    METABLOCK_HEADER:se -> METABLOCK_DONE:ne
+    METADATA:s -> METABLOCK_DONE:w
+    UNCOMPRESSED:s -> METABLOCK_DONE:n
+    METABLOCK_DONE:e -> METABLOCK_BEGIN:e [constraint="false"]
+  }
+  INITIALIZE -> METABLOCK_BEGIN
+  METABLOCK_DONE -> DONE
+
+  subgraph cluster_compressed_metablock {
+    style="rounded"
+    label=< <B>COMPRESSED METABLOCK</B> >
+
+    subgraph cluster_command {
+      style="rounded"
+      label=< <B>HOT LOOP</B> >
+
+      _METABLOCK_DONE_PORT_ [shape=point style=invis]
+
+      {
+        // Set different shape for nodes returning from "compressed metablock".
+        node [shape=invhouse]; CMD_INNER CMD_POST_DECODE_LITERALS;
+        CMD_POST_WRAP_COPY; CMD_INNER_WRITE; CMD_POST_WRITE_1;
+      }
+
+      CMD_BEGIN -> CMD_INNER -> CMD_POST_DECODE_LITERALS -> CMD_POST_WRAP_COPY
+
+      // IO ("write") nodes are not in the hot loop!
+      CMD_INNER_WRITE [style=dashed]
+      CMD_INNER -> CMD_INNER_WRITE
+      CMD_POST_WRITE_1 [style=dashed]
+      CMD_POST_DECODE_LITERALS -> CMD_POST_WRITE_1
+      CMD_POST_WRITE_2 [style=dashed]
+      CMD_POST_WRAP_COPY -> CMD_POST_WRITE_2
+
+      CMD_POST_WRITE_1 -> CMD_BEGIN:s [constraint="false"]
+      CMD_INNER_WRITE -> {CMD_INNER CMD_POST_DECODE_LITERALS}
+          [constraint="false"]
+      CMD_BEGIN:ne -> CMD_POST_DECODE_LITERALS [constraint="false"]
+      CMD_POST_WRAP_COPY -> CMD_BEGIN [constraint="false"]
+      CMD_POST_DECODE_LITERALS -> CMD_BEGIN:ne [constraint="false"]
+      CMD_POST_WRITE_2 -> CMD_POST_WRAP_COPY [constraint="false"]
+      {rank=same; CMD_BEGIN; CMD_INNER; CMD_POST_DECODE_LITERALS;
+          CMD_POST_WRAP_COPY}
+      {rank=same; CMD_INNER_WRITE; CMD_POST_WRITE_1; CMD_POST_WRITE_2}
+
+      {CMD_INNER CMD_POST_DECODE_LITERALS CMD_POST_WRAP_COPY} ->
+          _METABLOCK_DONE_PORT_ [style=invis]
+      {CMD_INNER_WRITE CMD_POST_WRITE_1} -> _METABLOCK_DONE_PORT_
+          [constraint="false" style=invis]
+    }
+
+    BEFORE_COMPRESSED_METABLOCK_HEADER:s -> HUFFMAN_CODE_0:n
+    HUFFMAN_CODE_0 -> HUFFMAN_CODE_1 -> HUFFMAN_CODE_2 -> HUFFMAN_CODE_3
+    HUFFMAN_CODE_0 -> METABLOCK_HEADER_2 -> CONTEXT_MODES -> CONTEXT_MAP_1
+    CONTEXT_MAP_1 -> CONTEXT_MAP_2 -> TREE_GROUP
+    TREE_GROUP -> BEFORE_COMPRESSED_METABLOCK_BODY:e
+    BEFORE_COMPRESSED_METABLOCK_BODY:s -> CMD_BEGIN:n
+
+    HUFFMAN_CODE_3:e -> HUFFMAN_CODE_0:ne [constraint="false"]
+    {rank=same; HUFFMAN_CODE_0; HUFFMAN_CODE_1; HUFFMAN_CODE_2; HUFFMAN_CODE_3}
+    {rank=same; METABLOCK_HEADER_2; CONTEXT_MODES; CONTEXT_MAP_1; CONTEXT_MAP_2;
+        TREE_GROUP}
+  }
+  METABLOCK_HEADER:e -> BEFORE_COMPRESSED_METABLOCK_HEADER:n
+
+  _METABLOCK_DONE_PORT_ -> METABLOCK_DONE:se
+      [constraint="false" ltail=cluster_command]
+
+  UNINITED [shape=Mdiamond];
+  DONE [shape=Msquare];
+}
+
+
+ */
+
+typedef enum {
+  BROTLI_STATE_UNINITED,
+  BROTLI_STATE_LARGE_WINDOW_BITS,
+  BROTLI_STATE_INITIALIZE,
+  BROTLI_STATE_METABLOCK_BEGIN,
+  BROTLI_STATE_METABLOCK_HEADER,
+  BROTLI_STATE_METABLOCK_HEADER_2,
+  BROTLI_STATE_CONTEXT_MODES,
+  BROTLI_STATE_COMMAND_BEGIN,
+  BROTLI_STATE_COMMAND_INNER,
+  BROTLI_STATE_COMMAND_POST_DECODE_LITERALS,
+  BROTLI_STATE_COMMAND_POST_WRAP_COPY,
+  BROTLI_STATE_UNCOMPRESSED,
+  BROTLI_STATE_METADATA,
+  BROTLI_STATE_COMMAND_INNER_WRITE,
+  BROTLI_STATE_METABLOCK_DONE,
+  BROTLI_STATE_COMMAND_POST_WRITE_1,
+  BROTLI_STATE_COMMAND_POST_WRITE_2,
+  BROTLI_STATE_BEFORE_COMPRESSED_METABLOCK_HEADER,
+  BROTLI_STATE_HUFFMAN_CODE_0,
+  BROTLI_STATE_HUFFMAN_CODE_1,
+  BROTLI_STATE_HUFFMAN_CODE_2,
+  BROTLI_STATE_HUFFMAN_CODE_3,
+  BROTLI_STATE_CONTEXT_MAP_1,
+  BROTLI_STATE_CONTEXT_MAP_2,
+  BROTLI_STATE_TREE_GROUP,
+  BROTLI_STATE_BEFORE_COMPRESSED_METABLOCK_BODY,
+  BROTLI_STATE_DONE
+} BrotliRunningState;
+
+typedef enum {
+  BROTLI_STATE_METABLOCK_HEADER_NONE,
+  BROTLI_STATE_METABLOCK_HEADER_EMPTY,
+  BROTLI_STATE_METABLOCK_HEADER_NIBBLES,
+  BROTLI_STATE_METABLOCK_HEADER_SIZE,
+  BROTLI_STATE_METABLOCK_HEADER_UNCOMPRESSED,
+  BROTLI_STATE_METABLOCK_HEADER_RESERVED,
+  BROTLI_STATE_METABLOCK_HEADER_BYTES,
+  BROTLI_STATE_METABLOCK_HEADER_METADATA
+} BrotliRunningMetablockHeaderState;
+
+typedef enum {
+  BROTLI_STATE_UNCOMPRESSED_NONE,
+  BROTLI_STATE_UNCOMPRESSED_WRITE
+} BrotliRunningUncompressedState;
+
+typedef enum {
+  BROTLI_STATE_TREE_GROUP_NONE,
+  BROTLI_STATE_TREE_GROUP_LOOP
+} BrotliRunningTreeGroupState;
+
+typedef enum {
+  BROTLI_STATE_CONTEXT_MAP_NONE,
+  BROTLI_STATE_CONTEXT_MAP_READ_PREFIX,
+  BROTLI_STATE_CONTEXT_MAP_HUFFMAN,
+  BROTLI_STATE_CONTEXT_MAP_DECODE,
+  BROTLI_STATE_CONTEXT_MAP_TRANSFORM
+} BrotliRunningContextMapState;
+
+typedef enum {
+  BROTLI_STATE_HUFFMAN_NONE,
+  BROTLI_STATE_HUFFMAN_SIMPLE_SIZE,
+  BROTLI_STATE_HUFFMAN_SIMPLE_READ,
+  BROTLI_STATE_HUFFMAN_SIMPLE_BUILD,
+  BROTLI_STATE_HUFFMAN_COMPLEX,
+  BROTLI_STATE_HUFFMAN_LENGTH_SYMBOLS
+} BrotliRunningHuffmanState;
+
+typedef enum {
+  BROTLI_STATE_DECODE_UINT8_NONE,
+  BROTLI_STATE_DECODE_UINT8_SHORT,
+  BROTLI_STATE_DECODE_UINT8_LONG
+} BrotliRunningDecodeUint8State;
+
+typedef enum {
+  BROTLI_STATE_READ_BLOCK_LENGTH_NONE,
+  BROTLI_STATE_READ_BLOCK_LENGTH_SUFFIX
+} BrotliRunningReadBlockLengthState;
+
+/* BrotliDecoderState addon, used for Compound Dictionary functionality. */
+typedef struct BrotliDecoderCompoundDictionary {
+  int num_chunks;
+  int total_size;
+  int br_index;
+  int br_offset;
+  int br_length;
+  int br_copied;
+  const uint8_t* chunks[16];
+  int chunk_offsets[16];
+  int block_bits;
+  uint8_t block_map[256];
+} BrotliDecoderCompoundDictionary;
+
+typedef struct BrotliMetablockHeaderArena {
+  BrotliRunningTreeGroupState substate_tree_group;
+  BrotliRunningContextMapState substate_context_map;
+  BrotliRunningHuffmanState substate_huffman;
+
+  brotli_reg_t sub_loop_counter;
+
+  brotli_reg_t repeat_code_len;
+  brotli_reg_t prev_code_len;
+
+  /* For ReadHuffmanCode. */
+  brotli_reg_t symbol;
+  brotli_reg_t repeat;
+  brotli_reg_t space;
+
+  /* Huffman table for "histograms". */
+  HuffmanCode table[32];
+  /* List of heads of symbol chains. */
+  uint16_t* symbol_lists;
+  /* Storage from symbol_lists. */
+  uint16_t symbols_lists_array[BROTLI_HUFFMAN_MAX_CODE_LENGTH + 1 +
+                               BROTLI_NUM_COMMAND_SYMBOLS];
+  /* Tails of symbol chains. */
+  int next_symbol[32];
+  uint8_t code_length_code_lengths[BROTLI_CODE_LENGTH_CODES];
+  /* Population counts for the code lengths. */
+  uint16_t code_length_histo[16];
+  /* TODO(eustas): +2 bytes padding */
+
+  /* For HuffmanTreeGroupDecode. */
+  int htree_index;
+  HuffmanCode* next;
+
+  /* For DecodeContextMap. */
+  brotli_reg_t context_index;
+  brotli_reg_t max_run_length_prefix;
+  brotli_reg_t code;
+  HuffmanCode context_map_table[BROTLI_HUFFMAN_MAX_SIZE_272];
+} BrotliMetablockHeaderArena;
+
+typedef struct BrotliMetablockBodyArena {
+  uint8_t dist_extra_bits[544];
+  brotli_reg_t dist_offset[544];
+} BrotliMetablockBodyArena;
+
+struct BrotliDecoderStateStruct {
+  BrotliRunningState state;
+
+  /* This counter is reused for several disjoint loops. */
+  int loop_counter;
+
+  BrotliBitReader br;
+
+  brotli_alloc_func alloc_func;
+  brotli_free_func free_func;
+  void* memory_manager_opaque;
+
+  /* Temporary storage for remaining input. Brotli stream format is designed in
+     a way, that 64 bits are enough to make progress in decoding. */
+  union {
+    uint64_t u64;
+    uint8_t u8[8];
+  } buffer;
+  brotli_reg_t buffer_length;
+
+  int pos;
+  int max_backward_distance;
+  int max_distance;
+  int ringbuffer_size;
+  int ringbuffer_mask;
+  int dist_rb_idx;
+  int dist_rb[4];
+  int error_code;
+  int meta_block_remaining_len;
+
+  uint8_t* ringbuffer;
+  uint8_t* ringbuffer_end;
+  HuffmanCode* htree_command;
+  const uint8_t* context_lookup;
+  uint8_t* context_map_slice;
+  uint8_t* dist_context_map_slice;
+
+  /* This ring buffer holds a few past copy distances that will be used by
+     some special distance codes. */
+  HuffmanTreeGroup literal_hgroup;
+  HuffmanTreeGroup insert_copy_hgroup;
+  HuffmanTreeGroup distance_hgroup;
+  HuffmanCode* block_type_trees;
+  HuffmanCode* block_len_trees;
+  /* This is true if the literal context map histogram type always matches the
+     block type. It is then not needed to keep the context (faster decoding). */
+  int trivial_literal_context;
+  /* Distance context is actual after command is decoded and before distance is
+     computed. After distance computation it is used as a temporary variable. */
+  int distance_context;
+  brotli_reg_t block_length[3];
+  brotli_reg_t block_length_index;
+  brotli_reg_t num_block_types[3];
+  brotli_reg_t block_type_rb[6];
+  brotli_reg_t distance_postfix_bits;
+  brotli_reg_t num_direct_distance_codes;
+  brotli_reg_t num_dist_htrees;
+  uint8_t* dist_context_map;
+  HuffmanCode* literal_htree;
+
+  /* For partial write operations. */
+  size_t rb_roundtrips;  /* how many times we went around the ring-buffer */
+  size_t partial_pos_out;  /* how much output to the user in total */
+
+  /* For InverseMoveToFrontTransform. */
+  brotli_reg_t mtf_upper_bound;
+  uint32_t mtf[64 + 1];
+
+  int copy_length;
+  int distance_code;
+
+  uint8_t dist_htree_index;
+  /* TODO(eustas): +3 bytes padding */
+
+  /* Less used attributes are at the end of this struct. */
+
+  brotli_decoder_metadata_start_func metadata_start_func;
+  brotli_decoder_metadata_chunk_func metadata_chunk_func;
+  void* metadata_callback_opaque;
+
+  /* For reporting. */
+  uint64_t used_input;  /* how many bytes of input are consumed */
+
+  /* States inside function calls. */
+  BrotliRunningMetablockHeaderState substate_metablock_header;
+  BrotliRunningUncompressedState substate_uncompressed;
+  BrotliRunningDecodeUint8State substate_decode_uint8;
+  BrotliRunningReadBlockLengthState substate_read_block_length;
+
+  int new_ringbuffer_size;
+  /* TODO(eustas): +4 bytes padding */
+
+  unsigned int is_last_metablock : 1;
+  unsigned int is_uncompressed : 1;
+  unsigned int is_metadata : 1;
+  unsigned int should_wrap_ringbuffer : 1;
+  unsigned int canny_ringbuffer_allocation : 1;
+  unsigned int large_window : 1;
+  unsigned int window_bits : 6;
+  unsigned int size_nibbles : 8;
+  /* TODO(eustas): +12 bits padding */
+
+  brotli_reg_t num_literal_htrees;
+  uint8_t* context_map;
+  uint8_t* context_modes;
+
+  BrotliSharedDictionary* dictionary;
+  BrotliDecoderCompoundDictionary* compound_dictionary;
+
+  uint32_t trivial_literal_contexts[8];  /* 256 bits */
+
+  union {
+    BrotliMetablockHeaderArena header;
+    BrotliMetablockBodyArena body;
+  } arena;
+};
+
+typedef struct BrotliDecoderStateStruct BrotliDecoderStateInternal;
+#define BrotliDecoderState BrotliDecoderStateInternal
+
+BROTLI_INTERNAL BROTLI_BOOL BrotliDecoderStateInit(BrotliDecoderState* s,
+    brotli_alloc_func alloc_func, brotli_free_func free_func, void* opaque);
+BROTLI_INTERNAL void BrotliDecoderStateCleanup(BrotliDecoderState* s);
+BROTLI_INTERNAL void BrotliDecoderStateMetablockBegin(BrotliDecoderState* s);
+BROTLI_INTERNAL void BrotliDecoderStateCleanupAfterMetablock(
+    BrotliDecoderState* s);
+BROTLI_INTERNAL BROTLI_BOOL BrotliDecoderHuffmanTreeGroupInit(
+    BrotliDecoderState* s, HuffmanTreeGroup* group,
+    brotli_reg_t alphabet_size_max, brotli_reg_t alphabet_size_limit,
+    brotli_reg_t ntrees);
+
+#define BROTLI_DECODER_ALLOC(S, L) S->alloc_func(S->memory_manager_opaque, L)
+
+#define BROTLI_DECODER_FREE(S, X) {          \
+  S->free_func(S->memory_manager_opaque, X); \
+  X = NULL;                                  \
+}
+
+/* Literal/Command/Distance block size maximum; same as maximum metablock size;
+   used as block size when there is no block switching. */
+#define BROTLI_BLOCK_SIZE_CAP (1U << 24)
+
+#if defined(__cplusplus) || defined(c_plusplus)
+}  /* extern "C" */
+#endif
+
+#endif  /* BROTLI_DEC_STATE_H_ */