/src/libzip/lib/zip_hash.c

Source
/*
  zip_hash.c -- hash table string -> uint64
  Copyright (C) 2015-2024 Dieter Baron and Thomas Klausner

  This file is part of libzip, a library to manipulate ZIP archives.
  The authors can be contacted at <info@libzip.org>

  Redistribution and use in source and binary forms, with or without
  modification, are permitted provided that the following conditions
  are met:
  1. Redistributions of source code must retain the above copyright
     notice, this list of conditions and the following disclaimer.
  2. Redistributions in binary form must reproduce the above copyright
     notice, this list of conditions and the following disclaimer in
     the documentation and/or other materials provided with the
     distribution.
  3. The names of the authors may not be used to endorse or promote
     products derived from this software without specific prior
     written permission.

  THIS SOFTWARE IS PROVIDED BY THE AUTHORS ``AS IS'' AND ANY EXPRESS
  OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
  WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY
  DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
  GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER
  IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
  OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN
  IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/

#include "zipint.h"
#include <stdlib.h>
#include <string.h>

#include "siphash.h"


/* hash table's fill ratio is kept between these by doubling/halfing its size as necessary */
#define HASH_MAX_FILL .75
#define HASH_MIN_FILL .01

/* but hash table size is kept between these */
#define HASH_MIN_SIZE 256
#define HASH_MAX_SIZE 0x80000000ul

struct zip_hash_entry {
    const zip_uint8_t *name;
    zip_int64_t orig_index;
    zip_int64_t current_index;
    struct zip_hash_entry *next;
    zip_uint64_t hash_value;
};
typedef struct zip_hash_entry zip_hash_entry_t;

struct zip_hash {
    zip_uint32_t table_size;
    zip_uint64_t nentries;
    zip_hash_entry_t **table;
    zip_uint8_t hash_key[16];
};


/* free list of entries */
static void free_list(zip_hash_entry_t *entry) {
    while (entry != NULL) {
        zip_hash_entry_t *next = entry->next;
        free(entry);
        entry = next;
    }
}


/* resize hash table; new_size must be a power of 2, can be larger or smaller than current size */
static bool hash_resize(zip_hash_t *hash, zip_uint32_t new_size, zip_error_t *error) {
    zip_hash_entry_t **new_table;

    if (new_size == hash->table_size) {
        return true;
    }

    if ((new_table = (zip_hash_entry_t **)calloc(new_size, sizeof(zip_hash_entry_t *))) == NULL) {
        zip_error_set(error, ZIP_ER_MEMORY, 0);
        return false;
    }

    if (hash->nentries > 0) {
        zip_uint32_t i;

        for (i = 0; i < hash->table_size; i++) {
            zip_hash_entry_t *entry = hash->table[i];
            while (entry) {
                zip_hash_entry_t *next = entry->next;

                zip_uint32_t new_index = entry->hash_value % new_size;

                entry->next = new_table[new_index];
                new_table[new_index] = entry;

                entry = next;
            }
        }
    }

    free(hash->table);
    hash->table = new_table;
    hash->table_size = new_size;

    return true;
}


static zip_uint32_t size_for_capacity(zip_uint64_t capacity) {
    double needed_size = capacity / HASH_MAX_FILL;
    zip_uint32_t v;

    if (needed_size > ZIP_UINT32_MAX) {
        v = ZIP_UINT32_MAX;
    }
    else {
        v = (zip_uint32_t)needed_size;
    }

    if (v > HASH_MAX_SIZE) {
        return HASH_MAX_SIZE;
    }

    /* From Bit Twiddling Hacks by Sean Eron Anderson <seander@cs.stanford.edu>
     (http://graphics.stanford.edu/~seander/bithacks.html#RoundUpPowerOf2). */

    v--;
    v |= v >> 1;
    v |= v >> 2;
    v |= v >> 4;
    v |= v >> 8;
    v |= v >> 16;
    v++;

    return v;
}


zip_hash_t *_zip_hash_new(zip_error_t *error) {
    zip_hash_t *hash;

    if ((hash = (zip_hash_t *)malloc(sizeof(zip_hash_t))) == NULL) {
        zip_error_set(error, ZIP_ER_MEMORY, 0);
        return NULL;
    }

    hash->table_size = 0;
    hash->nentries = 0;
    hash->table = NULL;
    if (!zip_secure_random(hash->hash_key, sizeof(hash->hash_key))) {
        free(hash);
        zip_error_set(error, ZIP_ER_INTERNAL, 0);
        return NULL;
    }

    return hash;
}


void _zip_hash_free(zip_hash_t *hash) {
    zip_uint32_t i;

    if (hash == NULL) {
        return;
    }

    if (hash->table != NULL) {
        for (i = 0; i < hash->table_size; i++) {
            if (hash->table[i] != NULL) {
                free_list(hash->table[i]);
            }
        }
        free(hash->table);
    }
    /* The hash key does not need to be securely erased. */
    free(hash);
}


/* insert into hash, return error on existence or memory issues */
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) {
    zip_uint64_t hash_value;
    zip_uint32_t table_index;
    zip_hash_entry_t *entry;

    if (hash == NULL || name == NULL || index > ZIP_INT64_MAX) {
        zip_error_set(error, ZIP_ER_INVAL, 0);
        return false;
    }

    if (hash->table_size == 0) {
        if (!hash_resize(hash, HASH_MIN_SIZE, error)) {
            return false;
        }
    }

    hash_value = siphash(name, hash->hash_key);
    table_index = hash_value % hash->table_size;

    for (entry = hash->table[table_index]; entry != NULL; entry = entry->next) {
        if (entry->hash_value == hash_value && strcmp((const char *)name, (const char *)entry->name) == 0) {
            if (((flags & ZIP_FL_UNCHANGED) && entry->orig_index != -1) || entry->current_index != -1) {
                zip_error_set(error, ZIP_ER_EXISTS, 0);
                return false;
            }
            else {
                break;
            }
        }
    }

    if (entry == NULL) {
        if ((entry = (zip_hash_entry_t *)malloc(sizeof(zip_hash_entry_t))) == NULL) {
            zip_error_set(error, ZIP_ER_MEMORY, 0);
            return false;
        }
        entry->name = name;
        entry->next = hash->table[table_index];
        hash->table[table_index] = entry;
        entry->hash_value = hash_value;
        entry->orig_index = -1;
        hash->nentries++;
        if (hash->nentries > hash->table_size * HASH_MAX_FILL && hash->table_size < HASH_MAX_SIZE) {
            if (!hash_resize(hash, hash->table_size * 2, error)) {
                return false;
            }
        }
    }

    if (flags & ZIP_FL_UNCHANGED) {
        entry->orig_index = (zip_int64_t)index;
    }
    entry->current_index = (zip_int64_t)index;

    return true;
}


/* remove entry from hash, error if not found */
bool _zip_hash_delete(zip_hash_t *hash, const zip_uint8_t *name, zip_error_t *error) {
    zip_uint64_t hash_value;
    zip_uint32_t index;
    zip_hash_entry_t *entry, *previous;

    if (hash == NULL || name == NULL) {
        zip_error_set(error, ZIP_ER_INVAL, 0);
        return false;
    }

    if (hash->nentries > 0) {
        hash_value = siphash(name, hash->hash_key);
        index = hash_value % hash->table_size;
        previous = NULL;
        entry = hash->table[index];
        while (entry) {
            if (entry->hash_value == hash_value && strcmp((const char *)name, (const char *)entry->name) == 0) {
                if (entry->orig_index == -1) {
                    if (previous) {
                        previous->next = entry->next;
                    }
                    else {
                        hash->table[index] = entry->next;
                    }
                    free(entry);
                    hash->nentries--;
                    if (hash->nentries < hash->table_size * HASH_MIN_FILL && hash->table_size > HASH_MIN_SIZE) {
                        if (!hash_resize(hash, hash->table_size / 2, error)) {
                            return false;
                        }
                    }
                }
                else {
                    entry->current_index = -1;
                }
                return true;
            }
            previous = entry;
            entry = entry->next;
        }
    }

    zip_error_set(error, ZIP_ER_NOENT, 0);
    return false;
}


/* find value for entry in hash, -1 if not found */
zip_int64_t _zip_hash_lookup(zip_hash_t *hash, const zip_uint8_t *name, zip_flags_t flags, zip_error_t *error) {
    zip_uint64_t hash_value;
    zip_uint32_t index;
    zip_hash_entry_t *entry;

    if (hash == NULL || name == NULL) {
        zip_error_set(error, ZIP_ER_INVAL, 0);
        return -1;
    }

    if (hash->nentries > 0) {
        hash_value = siphash(name, hash->hash_key);
        index = hash_value % hash->table_size;
        for (entry = hash->table[index]; entry != NULL; entry = entry->next) {
            if (strcmp((const char *)name, (const char *)entry->name) == 0) {
                if (flags & ZIP_FL_UNCHANGED) {
                    if (entry->orig_index != -1) {
                        return entry->orig_index;
                    }
                }
                else {
                    if (entry->current_index != -1) {
                        return entry->current_index;
                    }
                }
                break;
            }
        }
    }

    zip_error_set(error, ZIP_ER_NOENT, 0);
    return -1;
}


bool _zip_hash_reserve_capacity(zip_hash_t *hash, zip_uint64_t capacity, zip_error_t *error) {
    zip_uint32_t new_size;

    if (capacity == 0) {
        return true;
    }

    new_size = size_for_capacity(capacity);

    if (new_size <= hash->table_size) {
        return true;
    }

    if (!hash_resize(hash, new_size, error)) {
        return false;
    }

    return true;
}


bool _zip_hash_revert(zip_hash_t *hash, zip_error_t *error) {
    zip_uint32_t i;
    zip_hash_entry_t *entry, *previous;

    for (i = 0; i < hash->table_size; i++) {
        previous = NULL;
        entry = hash->table[i];
        while (entry) {
            if (entry->orig_index == -1) {
                zip_hash_entry_t *p;
                if (previous) {
                    previous->next = entry->next;
                }
                else {
                    hash->table[i] = entry->next;
                }
                p = entry;
                entry = entry->next;
                /* previous does not change */
                free(p);
                hash->nentries--;
            }
            else {
                entry->current_index = entry->orig_index;
                previous = entry;
                entry = entry->next;
            }
        }
    }

    if (hash->nentries < hash->table_size * HASH_MIN_FILL && hash->table_size > HASH_MIN_SIZE) {
        zip_uint32_t new_size = hash->table_size / 2;
        while (hash->nentries < new_size * HASH_MIN_FILL && new_size > HASH_MIN_SIZE) {
            new_size /= 2;
        }
        if (!hash_resize(hash, new_size, error)) {
            return false;
        }
    }

    return true;
}

Coverage Report

Created: 2026-10-14 06:52

Line	Count	Source
1		/*
2		zip_hash.c -- hash table string -> uint64
3		Copyright (C) 2015-2024 Dieter Baron and Thomas Klausner
4
5		This file is part of libzip, a library to manipulate ZIP archives.
6		The authors can be contacted at <info@libzip.org>
7
8		Redistribution and use in source and binary forms, with or without
9		modification, are permitted provided that the following conditions
10		are met:
11		1. Redistributions of source code must retain the above copyright
12		notice, this list of conditions and the following disclaimer.
13		2. Redistributions in binary form must reproduce the above copyright
14		notice, this list of conditions and the following disclaimer in
15		the documentation and/or other materials provided with the
16		distribution.
17		3. The names of the authors may not be used to endorse or promote
18		products derived from this software without specific prior
19		written permission.
20
21		THIS SOFTWARE IS PROVIDED BY THE AUTHORS ``AS IS'' AND ANY EXPRESS
22		OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
23		WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24		ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY
25		DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26		DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
27		GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
28		INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER
29		IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
30		OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN
31		IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
32		*/
33
34		#include "zipint.h"
35		#include <stdlib.h>
36		#include <string.h>
37
38		#include "siphash.h"
39
40
41		/* hash table's fill ratio is kept between these by doubling/halfing its size as necessary */
42	56.7k	#define HASH_MAX_FILL .75
43	0	#define HASH_MIN_FILL .01
44
45		/* but hash table size is kept between these */
46	0	#define HASH_MIN_SIZE 256
47	5.86k	#define HASH_MAX_SIZE 0x80000000ul
48
49		struct zip_hash_entry {
50		const zip_uint8_t *name;
51		zip_int64_t orig_index;
52		zip_int64_t current_index;
53		struct zip_hash_entry *next;
54		zip_uint64_t hash_value;
55		};
56		typedef struct zip_hash_entry zip_hash_entry_t;
57
58		struct zip_hash {
59		zip_uint32_t table_size;
60		zip_uint64_t nentries;
61		zip_hash_entry_t **table;
62		zip_uint8_t hash_key[16];
63		};
64
65
66		/* free list of entries */
67	20.8k	static void free_list(zip_hash_entry_t *entry) {
68	47.0k	while (entry != NULL) {
69	26.2k	zip_hash_entry_t *next = entry->next;
70	26.2k	free(entry);
71	26.2k	entry = next;
72	26.2k	}
73	20.8k	}
74
75
76		/* resize hash table; new_size must be a power of 2, can be larger or smaller than current size */
77	5.86k	static bool hash_resize(zip_hash_t hash, zip_uint32_t new_size, zip_error_t error) {
78	5.86k	zip_hash_entry_t **new_table;
79
80	5.86k	if (new_size == hash->table_size) {
81	0	return true;
82	0	}
83
84	5.86k	if ((new_table = (zip_hash_entry_t *)calloc(new_size, sizeof(zip_hash_entry_t ))) == NULL) {
85	0	zip_error_set(error, ZIP_ER_MEMORY, 0);
86	0	return false;
87	0	}
88
89	5.86k	if (hash->nentries > 0) {
90	1.56k	zip_uint32_t i;
91
92	3.12k	for (i = 0; i < hash->table_size; i++) {
93	1.56k	zip_hash_entry_t *entry = hash->table[i];
94	3.12k	while (entry) {
95	1.56k	zip_hash_entry_t *next = entry->next;
96
97	1.56k	zip_uint32_t new_index = entry->hash_value % new_size;
98
99	1.56k	entry->next = new_table[new_index];
100	1.56k	new_table[new_index] = entry;
101
102	1.56k	entry = next;
103	1.56k	}
104	1.56k	}
105	1.56k	}
106
107	5.86k	free(hash->table);
108	5.86k	hash->table = new_table;
109	5.86k	hash->table_size = new_size;
110
111	5.86k	return true;
112	5.86k	}
113
114
115	4.30k	static zip_uint32_t size_for_capacity(zip_uint64_t capacity) {
116	4.30k	double needed_size = capacity / HASH_MAX_FILL;
117	4.30k	zip_uint32_t v;
118
119	4.30k	if (needed_size > ZIP_UINT32_MAX) {
120	0	v = ZIP_UINT32_MAX;
121	0	}
122	4.30k	else {
123	4.30k	v = (zip_uint32_t)needed_size;
124	4.30k	}
125
126	4.30k	if (v > HASH_MAX_SIZE) {
127	0	return HASH_MAX_SIZE;
128	0	}
129
130		/* From Bit Twiddling Hacks by Sean Eron Anderson <seander@cs.stanford.edu>
131		(http://graphics.stanford.edu/~seander/bithacks.html#RoundUpPowerOf2). */
132
133	4.30k	v--;
134	4.30k	v \|= v >> 1;
135	4.30k	v \|= v >> 2;
136	4.30k	v \|= v >> 4;
137	4.30k	v \|= v >> 8;
138	4.30k	v \|= v >> 16;
139	4.30k	v++;
140
141	4.30k	return v;
142	4.30k	}
143
144
145	8.78k	zip_hash_t _zip_hash_new(zip_error_t error) {
146	8.78k	zip_hash_t *hash;
147
148	8.78k	if ((hash = (zip_hash_t *)malloc(sizeof(zip_hash_t))) == NULL) {
149	0	zip_error_set(error, ZIP_ER_MEMORY, 0);
150	0	return NULL;
151	0	}
152
153	8.78k	hash->table_size = 0;
154	8.78k	hash->nentries = 0;
155	8.78k	hash->table = NULL;
156	8.78k	if (!zip_secure_random(hash->hash_key, sizeof(hash->hash_key))) {
157	0	free(hash);
158	0	zip_error_set(error, ZIP_ER_INTERNAL, 0);
159	0	return NULL;
160	0	}
161
162	8.78k	return hash;
163	8.78k	}
164
165
166	8.78k	void _zip_hash_free(zip_hash_t *hash) {
167	8.78k	zip_uint32_t i;
168
169	8.78k	if (hash == NULL) {
170	0	return;
171	0	}
172
173	8.78k	if (hash->table != NULL) {
174	51.2k	for (i = 0; i < hash->table_size; i++) {
175	46.9k	if (hash->table[i] != NULL) {
176	20.8k	free_list(hash->table[i]);
177	20.8k	}
178	46.9k	}
179	4.30k	free(hash->table);
180	4.30k	}
181		/* The hash key does not need to be securely erased. */
182	8.78k	free(hash);
183	8.78k	}
184
185
186		/* insert into hash, return error on existence or memory issues */
187	26.2k	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) {
188	26.2k	zip_uint64_t hash_value;
189	26.2k	zip_uint32_t table_index;
190	26.2k	zip_hash_entry_t *entry;
191
192	26.2k	if (hash == NULL \|\| name == NULL \|\| index > ZIP_INT64_MAX) {
193	0	zip_error_set(error, ZIP_ER_INVAL, 0);
194	0	return false;
195	0	}
196
197	26.2k	if (hash->table_size == 0) {
198	0	if (!hash_resize(hash, HASH_MIN_SIZE, error)) {
199	0	return false;
200	0	}
201	0	}
202
203	26.2k	hash_value = siphash(name, hash->hash_key);
204	26.2k	table_index = hash_value % hash->table_size;
205
206	32.4k	for (entry = hash->table[table_index]; entry != NULL; entry = entry->next) {
207	6.25k	if (entry->hash_value == hash_value && strcmp((const char )name, (const char )entry->name) == 0) {
208	24	if (((flags & ZIP_FL_UNCHANGED) && entry->orig_index != -1) \|\| entry->current_index != -1) {
209	24	zip_error_set(error, ZIP_ER_EXISTS, 0);
210	24	return false;
211	24	}
212	0	else {
213	0	break;
214	0	}
215	24	}
216	6.25k	}
217
218	26.2k	if (entry == NULL) {
219	26.2k	if ((entry = (zip_hash_entry_t *)malloc(sizeof(zip_hash_entry_t))) == NULL) {
220	0	zip_error_set(error, ZIP_ER_MEMORY, 0);
221	0	return false;
222	0	}
223	26.2k	entry->name = name;
224	26.2k	entry->next = hash->table[table_index];
225	26.2k	hash->table[table_index] = entry;
226	26.2k	entry->hash_value = hash_value;
227	26.2k	entry->orig_index = -1;
228	26.2k	hash->nentries++;
229	26.2k	if (hash->nentries > hash->table_size * HASH_MAX_FILL && hash->table_size < HASH_MAX_SIZE) {
230	1.56k	if (!hash_resize(hash, hash->table_size * 2, error)) {
231	0	return false;
232	0	}
233	1.56k	}
234	26.2k	}
235
236	26.2k	if (flags & ZIP_FL_UNCHANGED) {
237	26.2k	entry->orig_index = (zip_int64_t)index;
238	26.2k	}
239	26.2k	entry->current_index = (zip_int64_t)index;
240
241	26.2k	return true;
242	26.2k	}
243
244
245		/* remove entry from hash, error if not found */
246	0	bool _zip_hash_delete(zip_hash_t hash, const zip_uint8_t name, zip_error_t *error) {
247	0	zip_uint64_t hash_value;
248	0	zip_uint32_t index;
249	0	zip_hash_entry_t entry, previous;
250
251	0	if (hash == NULL \|\| name == NULL) {
252	0	zip_error_set(error, ZIP_ER_INVAL, 0);
253	0	return false;
254	0	}
255
256	0	if (hash->nentries > 0) {
257	0	hash_value = siphash(name, hash->hash_key);
258	0	index = hash_value % hash->table_size;
259	0	previous = NULL;
260	0	entry = hash->table[index];
261	0	while (entry) {
262	0	if (entry->hash_value == hash_value && strcmp((const char )name, (const char )entry->name) == 0) {
263	0	if (entry->orig_index == -1) {
264	0	if (previous) {
265	0	previous->next = entry->next;
266	0	}
267	0	else {
268	0	hash->table[index] = entry->next;
269	0	}
270	0	free(entry);
271	0	hash->nentries--;
272	0	if (hash->nentries < hash->table_size * HASH_MIN_FILL && hash->table_size > HASH_MIN_SIZE) {
273	0	if (!hash_resize(hash, hash->table_size / 2, error)) {
274	0	return false;
275	0	}
276	0	}
277	0	}
278	0	else {
279	0	entry->current_index = -1;
280	0	}
281	0	return true;
282	0	}
283	0	previous = entry;
284	0	entry = entry->next;
285	0	}
286	0	}
287
288	0	zip_error_set(error, ZIP_ER_NOENT, 0);
289	0	return false;
290	0	}
291
292
293		/* find value for entry in hash, -1 if not found */
294	36.4k	zip_int64_t _zip_hash_lookup(zip_hash_t hash, const zip_uint8_t name, zip_flags_t flags, zip_error_t *error) {
295	36.4k	zip_uint64_t hash_value;
296	36.4k	zip_uint32_t index;
297	36.4k	zip_hash_entry_t *entry;
298
299	36.4k	if (hash == NULL \|\| name == NULL) {
300	0	zip_error_set(error, ZIP_ER_INVAL, 0);
301	0	return -1;
302	0	}
303
304	36.4k	if (hash->nentries > 0) {
305	34.1k	hash_value = siphash(name, hash->hash_key);
306	34.1k	index = hash_value % hash->table_size;
307	50.3k	for (entry = hash->table[index]; entry != NULL; entry = entry->next) {
308	26.7k	if (strcmp((const char )name, (const char )entry->name) == 0) {
309	10.4k	if (flags & ZIP_FL_UNCHANGED) {
310	10.4k	if (entry->orig_index != -1) {
311	10.4k	return entry->orig_index;
312	10.4k	}
313	10.4k	}
314	44	else {
315	44	if (entry->current_index != -1) {
316	44	return entry->current_index;
317	44	}
318	44	}
319	0	break;
320	10.4k	}
321	26.7k	}
322	34.1k	}
323
324	25.9k	zip_error_set(error, ZIP_ER_NOENT, 0);
325	25.9k	return -1;
326	36.4k	}
327
328
329	4.63k	bool _zip_hash_reserve_capacity(zip_hash_t hash, zip_uint64_t capacity, zip_error_t error) {
330	4.63k	zip_uint32_t new_size;
331
332	4.63k	if (capacity == 0) {
333	332	return true;
334	332	}
335
336	4.30k	new_size = size_for_capacity(capacity);
337
338	4.30k	if (new_size <= hash->table_size) {
339	0	return true;
340	0	}
341
342	4.30k	if (!hash_resize(hash, new_size, error)) {
343	0	return false;
344	0	}
345
346	4.30k	return true;
347	4.30k	}
348
349
350	0	bool _zip_hash_revert(zip_hash_t hash, zip_error_t error) {
351	0	zip_uint32_t i;
352	0	zip_hash_entry_t entry, previous;
353
354	0	for (i = 0; i < hash->table_size; i++) {
355	0	previous = NULL;
356	0	entry = hash->table[i];
357	0	while (entry) {
358	0	if (entry->orig_index == -1) {
359	0	zip_hash_entry_t *p;
360	0	if (previous) {
361	0	previous->next = entry->next;
362	0	}
363	0	else {
364	0	hash->table[i] = entry->next;
365	0	}
366	0	p = entry;
367	0	entry = entry->next;
368		/* previous does not change */
369	0	free(p);
370	0	hash->nentries--;
371	0	}
372	0	else {
373	0	entry->current_index = entry->orig_index;
374	0	previous = entry;
375	0	entry = entry->next;
376	0	}
377	0	}
378	0	}
379
380	0	if (hash->nentries < hash->table_size * HASH_MIN_FILL && hash->table_size > HASH_MIN_SIZE) {
381	0	zip_uint32_t new_size = hash->table_size / 2;
382	0	while (hash->nentries < new_size * HASH_MIN_FILL && new_size > HASH_MIN_SIZE) {
383	0	new_size /= 2;
384	0	}
385	0	if (!hash_resize(hash, new_size, error)) {
386	0	return false;
387	0	}
388	0	}
389
390	0	return true;
391	0	}