Coverage Report

Created: 2026-09-14 07:37

next uncovered line (L), next uncovered region (R), next uncovered branch (B)
/src/libzip/lib/zip_hash.c
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/*
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  zip_hash.c -- hash table string -> uint64
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  Copyright (C) 2015-2024 Dieter Baron and Thomas Klausner
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  This file is part of libzip, a library to manipulate ZIP archives.
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  The authors can be contacted at <info@libzip.org>
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  Redistribution and use in source and binary forms, with or without
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  modification, are permitted provided that the following conditions
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  are met:
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  1. Redistributions of source code must retain the above copyright
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     notice, this list of conditions and the following disclaimer.
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  2. Redistributions in binary form must reproduce the above copyright
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     notice, this list of conditions and the following disclaimer in
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     the documentation and/or other materials provided with the
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     distribution.
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  3. The names of the authors may not be used to endorse or promote
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     products derived from this software without specific prior
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     written permission.
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  THIS SOFTWARE IS PROVIDED BY THE AUTHORS ``AS IS'' AND ANY EXPRESS
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  OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
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  WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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  ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY
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  DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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  DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
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  GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
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  INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER
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  IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
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  OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN
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  IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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*/
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#include "zip.h"
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#include "zipint.h"
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#include <stdlib.h>
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#include <string.h>
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#include "siphash.h"
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/* hash table's fill ratio is kept between these by doubling/halfing its size as necessary */
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0
#define HASH_MAX_FILL .75
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0
#define HASH_MIN_FILL .01
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/* but hash table size is kept between these */
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0
#define HASH_MIN_SIZE 256
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0
#define HASH_MAX_SIZE 0x80000000ul
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struct zip_hash_entry {
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    const zip_uint8_t *name;
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    zip_int64_t orig_index;
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    zip_int64_t current_index;
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    struct zip_hash_entry *next;
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    zip_uint64_t hash_value;
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};
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typedef struct zip_hash_entry zip_hash_entry_t;
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struct zip_hash {
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    zip_uint32_t table_size;
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    zip_uint64_t nentries;
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    zip_hash_entry_t **table;
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    zip_uint8_t hash_key[16];
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};
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/* free list of entries */
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0
static void free_list(zip_hash_entry_t *entry) {
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0
    while (entry != NULL) {
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0
        zip_hash_entry_t *next = entry->next;
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0
        free(entry);
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0
        entry = next;
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0
    }
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0
}
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/* resize hash table; new_size must be a power of 2, can be larger or smaller than current size */
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0
static bool hash_resize(zip_hash_t *hash, zip_uint32_t new_size, zip_error_t *error) {
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0
    zip_hash_entry_t **new_table;
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0
    if (new_size == hash->table_size) {
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0
        return true;
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0
    }
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0
    if ((new_table = (zip_hash_entry_t **)calloc(new_size, sizeof(zip_hash_entry_t *))) == NULL) {
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0
        zip_error_set(error, ZIP_ER_MEMORY, 0);
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0
        return false;
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0
    }
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0
    if (hash->nentries > 0) {
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0
        zip_uint32_t i;
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0
        for (i = 0; i < hash->table_size; i++) {
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0
            zip_hash_entry_t *entry = hash->table[i];
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0
            while (entry) {
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0
                zip_hash_entry_t *next = entry->next;
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                zip_uint32_t new_index = entry->hash_value % new_size;
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                entry->next = new_table[new_index];
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0
                new_table[new_index] = entry;
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                entry = next;
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0
            }
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0
        }
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0
    }
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0
    free(hash->table);
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0
    hash->table = new_table;
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0
    hash->table_size = new_size;
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    return true;
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0
}
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0
static zip_uint32_t size_for_capacity(zip_uint64_t capacity) {
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0
    double needed_size = capacity / HASH_MAX_FILL;
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    zip_uint32_t v;
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0
    if (needed_size > ZIP_UINT32_MAX) {
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0
        v = ZIP_UINT32_MAX;
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0
    }
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    else {
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0
        v = (zip_uint32_t)needed_size;
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    }
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    if (v > HASH_MAX_SIZE) {
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0
        return HASH_MAX_SIZE;
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0
    }
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    /* From Bit Twiddling Hacks by Sean Eron Anderson <seander@cs.stanford.edu>
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     (http://graphics.stanford.edu/~seander/bithacks.html#RoundUpPowerOf2). */
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0
    v--;
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0
    v |= v >> 1;
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    v |= v >> 2;
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    v |= v >> 4;
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    v |= v >> 8;
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0
    v |= v >> 16;
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    v++;
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    return v;
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0
}
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0
zip_hash_t *_zip_hash_new(zip_error_t *error) {
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    zip_hash_t *hash;
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0
    if ((hash = (zip_hash_t *)malloc(sizeof(zip_hash_t))) == NULL) {
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        zip_error_set(error, ZIP_ER_MEMORY, 0);
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        return NULL;
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0
    }
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    hash->table_size = 0;
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    hash->nentries = 0;
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    hash->table = NULL;
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    if (!zip_secure_random(hash->hash_key, sizeof(hash->hash_key))) {
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0
        free(hash);
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0
        zip_error_set(error, ZIP_ER_INTERNAL, 0);
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0
        return NULL;
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0
    }
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0
    return hash;
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0
}
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0
void _zip_hash_free(zip_hash_t *hash) {
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0
    zip_uint32_t i;
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0
    if (hash == NULL) {
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0
        return;
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0
    }
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0
    if (hash->table != NULL) {
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0
        for (i = 0; i < hash->table_size; i++) {
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0
            if (hash->table[i] != NULL) {
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0
                free_list(hash->table[i]);
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0
            }
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0
        }
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0
        free(hash->table);
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0
    }
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    /* The hash key does not need to be securely erased. */
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0
    free(hash);
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0
}
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/* insert into hash, return error on existence or memory issues */
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0
bool _zip_hash_add(zip_hash_t *hash, const zip_uint8_t *name, zip_uint64_t index, zip_flags_t flags, zip_error_t *error) {
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0
    zip_uint64_t hash_value;
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0
    zip_uint32_t table_index;
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0
    zip_hash_entry_t *entry;
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0
    if (hash == NULL || name == NULL || index > ZIP_INT64_MAX) {
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0
        zip_error_set(error, ZIP_ER_INVAL, 0);
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0
        return false;
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0
    }
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0
    if (hash->table_size == 0) {
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0
        if (!hash_resize(hash, HASH_MIN_SIZE, error)) {
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0
            return false;
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0
        }
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0
    }
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0
    hash_value = siphash(name, hash->hash_key);
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0
    table_index = hash_value % hash->table_size;
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0
    for (entry = hash->table[table_index]; entry != NULL; entry = entry->next) {
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0
        if (entry->hash_value == hash_value && strcmp((const char *)name, (const char *)entry->name) == 0) {
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0
            if (((flags & ZIP_FL_UNCHANGED) && entry->orig_index != -1) || entry->current_index != -1) {
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0
                zip_error_set(error, ZIP_ER_EXISTS, 0);
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0
                return false;
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0
            }
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0
            else {
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0
                break;
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0
            }
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0
        }
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0
    }
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0
    if (entry == NULL) {
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0
        if ((entry = (zip_hash_entry_t *)malloc(sizeof(zip_hash_entry_t))) == NULL) {
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0
            zip_error_set(error, ZIP_ER_MEMORY, 0);
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0
            return false;
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0
        }
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0
        entry->name = name;
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0
        entry->next = hash->table[table_index];
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0
        hash->table[table_index] = entry;
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0
        entry->hash_value = hash_value;
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0
        entry->orig_index = -1;
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0
        hash->nentries++;
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0
        if (hash->nentries > hash->table_size * HASH_MAX_FILL && hash->table_size < HASH_MAX_SIZE) {
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0
            if (!hash_resize(hash, hash->table_size * 2, error)) {
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0
                return false;
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0
            }
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0
        }
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0
    }
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0
    if (flags & ZIP_FL_UNCHANGED) {
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0
        entry->orig_index = (zip_int64_t)index;
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0
    }
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0
    entry->current_index = (zip_int64_t)index;
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0
    return true;
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0
}
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/* remove entry from hash, error if not found */
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0
bool _zip_hash_delete(zip_hash_t *hash, const zip_uint8_t *name, zip_error_t *error) {
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0
    zip_uint64_t hash_value;
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0
    zip_uint32_t index;
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0
    zip_hash_entry_t *entry, *previous;
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0
    if (hash == NULL || name == NULL) {
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0
        zip_error_set(error, ZIP_ER_INVAL, 0);
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0
        return false;
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0
    }
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257
0
    if (hash->nentries > 0) {
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0
        hash_value = siphash(name, hash->hash_key);
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0
        index = hash_value % hash->table_size;
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0
        previous = NULL;
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0
        entry = hash->table[index];
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0
        while (entry) {
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0
            if (entry->hash_value == hash_value && strcmp((const char *)name, (const char *)entry->name) == 0) {
264
0
                if (entry->orig_index == -1) {
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0
                    if (previous) {
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0
                        previous->next = entry->next;
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0
                    }
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0
                    else {
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0
                        hash->table[index] = entry->next;
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0
                    }
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0
                    free(entry);
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0
                    hash->nentries--;
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0
                    if (hash->nentries < hash->table_size * HASH_MIN_FILL && hash->table_size > HASH_MIN_SIZE) {
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0
                        if (!hash_resize(hash, hash->table_size / 2, error)) {
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0
                            return false;
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0
                        }
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0
                    }
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0
                }
279
0
                else {
280
0
                    entry->current_index = -1;
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0
                }
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0
                return true;
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0
            }
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0
            previous = entry;
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0
            entry = entry->next;
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0
        }
287
0
    }
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289
0
    zip_error_set(error, ZIP_ER_NOENT, 0);
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0
    return false;
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0
}
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/* find value for entry in hash, -1 if not found */
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0
zip_int64_t _zip_hash_lookup(zip_hash_t *hash, const zip_uint8_t *name, zip_flags_t flags, zip_error_t *error) {
296
0
    zip_uint64_t hash_value;
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0
    zip_uint32_t index;
298
0
    zip_hash_entry_t *entry;
299
300
0
    if (hash == NULL || name == NULL) {
301
0
        zip_error_set(error, ZIP_ER_INVAL, 0);
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0
        return -1;
303
0
    }
304
305
0
    if (hash->nentries > 0) {
306
0
        hash_value = siphash(name, hash->hash_key);
307
0
        index = hash_value % hash->table_size;
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0
        for (entry = hash->table[index]; entry != NULL; entry = entry->next) {
309
0
            if (strcmp((const char *)name, (const char *)entry->name) == 0) {
310
0
                if (flags & ZIP_FL_UNCHANGED) {
311
0
                    if (entry->orig_index != -1) {
312
0
                        return entry->orig_index;
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0
                    }
314
0
                }
315
0
                else {
316
0
                    if (entry->current_index != -1) {
317
0
                        return entry->current_index;
318
0
                    }
319
0
                }
320
0
                break;
321
0
            }
322
0
        }
323
0
    }
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0
    zip_error_set(error, ZIP_ER_NOENT, 0);
326
0
    return -1;
327
0
}
328
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330
0
bool _zip_hash_reserve_capacity(zip_hash_t *hash, zip_uint64_t capacity, zip_error_t *error) {
331
0
    zip_uint32_t new_size;
332
333
0
    if (capacity == 0) {
334
0
        return true;
335
0
    }
336
337
0
    new_size = size_for_capacity(capacity);
338
339
0
    if (new_size <= hash->table_size) {
340
0
        return true;
341
0
    }
342
343
0
    if (!hash_resize(hash, new_size, error)) {
344
0
        return false;
345
0
    }
346
347
0
    return true;
348
0
}
349
350
351
0
bool _zip_hash_revert(zip_hash_t *hash, zip_error_t *error) {
352
0
    zip_uint32_t i;
353
0
    zip_hash_entry_t *entry, *previous;
354
355
0
    for (i = 0; i < hash->table_size; i++) {
356
0
        previous = NULL;
357
0
        entry = hash->table[i];
358
0
        while (entry) {
359
0
            if (entry->orig_index == -1) {
360
0
                zip_hash_entry_t *p;
361
0
                if (previous) {
362
0
                    previous->next = entry->next;
363
0
                }
364
0
                else {
365
0
                    hash->table[i] = entry->next;
366
0
                }
367
0
                p = entry;
368
0
                entry = entry->next;
369
                /* previous does not change */
370
0
                free(p);
371
0
                hash->nentries--;
372
0
            }
373
0
            else {
374
0
                entry->current_index = entry->orig_index;
375
0
                previous = entry;
376
0
                entry = entry->next;
377
0
            }
378
0
        }
379
0
    }
380
381
0
    if (hash->nentries < hash->table_size * HASH_MIN_FILL && hash->table_size > HASH_MIN_SIZE) {
382
0
        zip_uint32_t new_size = hash->table_size / 2;
383
0
        while (hash->nentries < new_size * HASH_MIN_FILL && new_size > HASH_MIN_SIZE) {
384
0
            new_size /= 2;
385
0
        }
386
0
        if (!hash_resize(hash, new_size, error)) {
387
0
            return false;
388
0
        }
389
0
    }
390
391
0
    return true;
392
0
}