afiqzudinhadi
1d5bef3129
Spare slots (1.23x) doubled binary size → reverted to v2 (no spare slots, entry_count == slot_count). CHD now uses entry_count/4 buckets and 1M displacement tries instead of 65K. No trimming.
68 lines
1.8 KiB
C
68 lines
1.8 KiB
C
/**
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* MPHF (Minimal Perfect Hash Function) dictionary lookup engine.
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*
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* Binary format v2: CHD MPHF + bit-packed displacements/values +
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* fingerprinted verification + block-compressed string table.
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*
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* SPDX-License-Identifier: PolyForm-Noncommercial-1.0.0
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*/
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#ifndef DICT_MPHF_H
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#define DICT_MPHF_H
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#include <stdint.h>
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#include <stdbool.h>
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#include <stddef.h>
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#define DICT_MPHF_MAGIC 0x4F4E5453 /* "STNO" */
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#define DICT_MPHF_VERSION 2
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#define DICT_MPHF_FLAG_COMPRESSED 0x0001
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struct dict_mphf_header {
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uint32_t magic;
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uint16_t version;
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uint16_t flags;
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uint32_t entry_count;
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uint32_t bucket_count;
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uint32_t unique_count;
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uint8_t value_bits;
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uint8_t disp_bits;
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uint16_t prefix_count;
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uint32_t block_size;
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uint32_t reserved1;
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} __attribute__((packed));
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_Static_assert(sizeof(struct dict_mphf_header) == 32, "header must be 32 bytes");
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struct dict_mphf {
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const struct dict_mphf_header *header;
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const uint8_t *displacements;
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const uint8_t *values;
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const uint8_t *fingerprints;
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const uint8_t *string_offsets;
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const uint8_t *str_data_start;
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const uint32_t *prefix_table;
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uint32_t disp_section_len;
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uint32_t val_section_len;
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uint32_t fp_section_len;
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uint16_t block_count;
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const uint32_t *block_dir;
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const uint8_t *blocks_start;
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uint32_t str_data_len;
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uint32_t blk_size;
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};
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int dict_mphf_init(struct dict_mphf *dict, const void *data, size_t len);
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const char *dict_mphf_lookup(const struct dict_mphf *dict,
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const uint32_t *strokes, uint8_t count);
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bool dict_mphf_has_prefix(const struct dict_mphf *dict, uint32_t stroke);
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static inline uint32_t dict_mphf_count(const struct dict_mphf *dict)
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{
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return dict->header->entry_count;
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}
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#endif /* DICT_MPHF_H */
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