2 * This program is free software; you can redistribute it and/or modify
3 * it under the terms of the GNU General Public License as published by
4 * the Free Software Foundation; either version 2 of the License, or
5 * (at your option) any later version.
6 * Please read the file COPYING, README and AUTHORS for more information.
8 * libarray - dynamically allocate arrays.
9 * Copyright (c) 2005 Florian Westphal (westphal@foo.fh-furtwangen.de)
14 * Functions to dynamically allocate arrays.
26 /* Enable more Debug messages in alloc / append / memmove code. */
27 /* #define DEBUG_ARRAY */
31 #define array_UNUSABLE(x) ( !(x)->mem )
33 safemult_sizet(size_t a, size_t b, size_t *res)
37 if (b && (tmp / b != a))
55 /* if realloc() fails, array_alloc return NULL. otherwise return pointer to elem pos in array */
57 array_alloc(array * a, size_t size, size_t pos)
59 size_t alloc, pos_plus1 = pos + 1;
64 if (pos_plus1 == 0 || !safemult_sizet(size, pos_plus1, &alloc))
67 if (a->allocated < alloc) {
69 Log(LOG_DEBUG, "array_alloc(): changing size from %u to %u bytes.",
72 tmp = realloc(a->mem, alloc);
78 memset(a->mem + a->used, 0, a->allocated - a->used);
82 assert(a->allocated >= a->used);
84 return a->mem + (pos * size);
88 /*return number of initialized ELEMS in a. */
90 array_length(const array * const a, size_t membersize)
93 assert(membersize > 0);
95 if (array_UNUSABLE(a))
99 return membersize ? a->used / membersize : 0;
103 /* copy array src to array dest */
105 array_copy(array * dest, const array * const src)
107 if (array_UNUSABLE(src))
110 assert(src->allocated);
111 return array_copyb(dest, src->mem, src->used);
115 /* return false on failure (realloc failure, invalid src/dest array) */
117 array_copyb(array * dest, const char *src, size_t len)
119 assert(dest != NULL);
120 assert(src != NULL );
126 return array_catb(dest, src, len);
130 /* copy string to dest */
132 array_copys(array * dest, const char *src)
134 return array_copyb(dest, src, strlen(src));
138 /* append len bytes from src to the array dest.
139 return false if we could not append all bytes (realloc failure, invalid src/dest array) */
141 array_catb(array * dest, const char *src, size_t len)
147 assert(dest != NULL);
159 if (tmp < used || tmp < len) /* integer overflow */
162 if (!array_alloc(dest, 1, tmp))
171 "array_catb(): appending %u bytes to array (now %u bytes in array).",
174 memcpy(ptr + used, src, len);
180 /* append string to dest */
182 array_cats(array * dest, const char *src)
184 return array_catb(dest, src, strlen(src));
188 /* append trailing NUL byte to array */
190 array_cat0(array * a)
192 return array_catb(a, "", 1);
196 /* append trailing NUL byte to array, but do not count it. */
198 array_cat0_temporary(array * a)
200 char *endpos = array_alloc(a, 1, array_bytes(a));
208 /* add contents of array src to array dest. */
210 array_cat(array * dest, const array * const src)
212 if (array_UNUSABLE(src))
215 return array_catb(dest, src->mem, src->used);
219 /* return pointer to the element at pos.
220 return NULL if the array is unallocated, or if pos is larger than
221 the number of elements stored int the array. */
223 array_get(array * a, size_t membersize, size_t pos)
226 size_t posplus1 = pos + 1;
228 assert(membersize > 0);
231 if (!posplus1 || array_UNUSABLE(a))
234 if (!safemult_sizet(posplus1, membersize, &totalsize))
237 if (a->allocated < totalsize)
240 totalsize = pos * membersize;
241 return a->mem + totalsize;
246 array_free(array * a)
251 "array_free(): %u bytes free'd (%u bytes still used at time of free()).",
252 a->allocated, a->used);
261 array_free_wipe(array *a)
263 size_t bytes = a->allocated;
265 memset(a->mem, 0, bytes);
270 array_start(const array * const a)
278 array_trunc(array * a)
286 array_truncate(array * a, size_t membersize, size_t len)
290 if (!safemult_sizet(membersize, len, &newlen))
293 if (newlen <= a->allocated)
298 /* move elements starting at pos to beginning of array */
300 array_moveleft(array * a, size_t membersize, size_t pos)
305 assert(membersize > 0);
307 if (!safemult_sizet(membersize, pos, &bytepos)) {
313 return; /* nothing to do */
317 "array_moveleft(): %u bytes used in array, starting at position %u.",
320 if (a->used <= bytepos) {
326 memmove(a->mem, a->mem + bytepos, a->used);