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-rw-r--r--gl/xmalloc.c303
1 files changed, 260 insertions, 43 deletions
diff --git a/gl/xmalloc.c b/gl/xmalloc.c
index 57e34b7..d5def0b 100644
--- a/gl/xmalloc.c
+++ b/gl/xmalloc.c
@@ -1,6 +1,6 @@
1/* xmalloc.c -- malloc with out of memory checking 1/* xmalloc.c -- malloc with out of memory checking
2 2
3 Copyright (C) 1990-2000, 2002-2006, 2008-2013 Free Software Foundation, Inc. 3 Copyright (C) 1990-2000, 2002-2006, 2008-2021 Free Software Foundation, Inc.
4 4
5 This program is free software: you can redistribute it and/or modify 5 This program is free software: you can redistribute it and/or modify
6 it under the terms of the GNU General Public License as published by 6 it under the terms of the GNU General Public License as published by
@@ -13,7 +13,7 @@
13 GNU General Public License for more details. 13 GNU General Public License for more details.
14 14
15 You should have received a copy of the GNU General Public License 15 You should have received a copy of the GNU General Public License
16 along with this program. If not, see <http://www.gnu.org/licenses/>. */ 16 along with this program. If not, see <https://www.gnu.org/licenses/>. */
17 17
18#include <config.h> 18#include <config.h>
19 19
@@ -21,59 +21,255 @@
21 21
22#include "xalloc.h" 22#include "xalloc.h"
23 23
24#include "ialloc.h"
25#include "intprops.h"
26#include "minmax.h"
27
24#include <stdlib.h> 28#include <stdlib.h>
25#include <string.h> 29#include <string.h>
26 30
27/* 1 if calloc is known to be compatible with GNU calloc. This 31static void * _GL_ATTRIBUTE_PURE
28 matters if we are not also using the calloc module, which defines 32nonnull (void *p)
29 HAVE_CALLOC_GNU and supports the GNU API even on non-GNU platforms. */ 33{
30#if defined HAVE_CALLOC_GNU || (defined __GLIBC__ && !defined __UCLIBC__) 34 if (!p)
31enum { HAVE_GNU_CALLOC = 1 }; 35 xalloc_die ();
32#else 36 return p;
33enum { HAVE_GNU_CALLOC = 0 }; 37}
34#endif
35 38
36/* Allocate N bytes of memory dynamically, with error checking. */ 39/* Allocate S bytes of memory dynamically, with error checking. */
37 40
38void * 41void *
39xmalloc (size_t n) 42xmalloc (size_t s)
40{ 43{
41 void *p = malloc (n); 44 return nonnull (malloc (s));
42 if (!p && n != 0) 45}
43 xalloc_die (); 46
44 return p; 47void *
48ximalloc (idx_t s)
49{
50 return nonnull (imalloc (s));
45} 51}
46 52
47/* Change the size of an allocated block of memory P to N bytes, 53char *
54xcharalloc (size_t n)
55{
56 return XNMALLOC (n, char);
57}
58
59/* Change the size of an allocated block of memory P to S bytes,
48 with error checking. */ 60 with error checking. */
49 61
50void * 62void *
51xrealloc (void *p, size_t n) 63xrealloc (void *p, size_t s)
64{
65 void *r = realloc (p, s);
66 if (!r && (!p || s))
67 xalloc_die ();
68 return r;
69}
70
71void *
72xirealloc (void *p, idx_t s)
73{
74 return nonnull (irealloc (p, s));
75}
76
77/* Change the size of an allocated block of memory P to an array of N
78 objects each of S bytes, with error checking. */
79
80void *
81xreallocarray (void *p, size_t n, size_t s)
82{
83 void *r = reallocarray (p, n, s);
84 if (!r && (!p || (n && s)))
85 xalloc_die ();
86 return r;
87}
88
89void *
90xireallocarray (void *p, idx_t n, idx_t s)
91{
92 return nonnull (ireallocarray (p, n, s));
93}
94
95/* Allocate an array of N objects, each with S bytes of memory,
96 dynamically, with error checking. S must be nonzero. */
97
98void *
99xnmalloc (size_t n, size_t s)
100{
101 return xreallocarray (NULL, n, s);
102}
103
104void *
105xinmalloc (idx_t n, idx_t s)
106{
107 return xireallocarray (NULL, n, s);
108}
109
110/* If P is null, allocate a block of at least *PS bytes; otherwise,
111 reallocate P so that it contains more than *PS bytes. *PS must be
112 nonzero unless P is null. Set *PS to the new block's size, and
113 return the pointer to the new block. *PS is never set to zero, and
114 the returned pointer is never null. */
115
116void *
117x2realloc (void *p, size_t *ps)
118{
119 return x2nrealloc (p, ps, 1);
120}
121
122/* If P is null, allocate a block of at least *PN such objects;
123 otherwise, reallocate P so that it contains more than *PN objects
124 each of S bytes. S must be nonzero. Set *PN to the new number of
125 objects, and return the pointer to the new block. *PN is never set
126 to zero, and the returned pointer is never null.
127
128 Repeated reallocations are guaranteed to make progress, either by
129 allocating an initial block with a nonzero size, or by allocating a
130 larger block.
131
132 In the following implementation, nonzero sizes are increased by a
133 factor of approximately 1.5 so that repeated reallocations have
134 O(N) overall cost rather than O(N**2) cost, but the
135 specification for this function does not guarantee that rate.
136
137 Here is an example of use:
138
139 int *p = NULL;
140 size_t used = 0;
141 size_t allocated = 0;
142
143 void
144 append_int (int value)
145 {
146 if (used == allocated)
147 p = x2nrealloc (p, &allocated, sizeof *p);
148 p[used++] = value;
149 }
150
151 This causes x2nrealloc to allocate a block of some nonzero size the
152 first time it is called.
153
154 To have finer-grained control over the initial size, set *PN to a
155 nonzero value before calling this function with P == NULL. For
156 example:
157
158 int *p = NULL;
159 size_t used = 0;
160 size_t allocated = 0;
161 size_t allocated1 = 1000;
162
163 void
164 append_int (int value)
165 {
166 if (used == allocated)
167 {
168 p = x2nrealloc (p, &allocated1, sizeof *p);
169 allocated = allocated1;
170 }
171 p[used++] = value;
172 }
173
174 */
175
176void *
177x2nrealloc (void *p, size_t *pn, size_t s)
52{ 178{
53 if (!n && p) 179 size_t n = *pn;
180
181 if (! p)
54 { 182 {
55 /* The GNU and C99 realloc behaviors disagree here. Act like 183 if (! n)
56 GNU, even if the underlying realloc is C99. */ 184 {
57 free (p); 185 /* The approximate size to use for initial small allocation
58 return NULL; 186 requests, when the invoking code specifies an old size of
187 zero. This is the largest "small" request for the GNU C
188 library malloc. */
189 enum { DEFAULT_MXFAST = 64 * sizeof (size_t) / 4 };
190
191 n = DEFAULT_MXFAST / s;
192 n += !n;
193 }
194 }
195 else
196 {
197 /* Set N = floor (1.5 * N) + 1 to make progress even if N == 0. */
198 if (INT_ADD_WRAPV (n, (n >> 1) + 1, &n))
199 xalloc_die ();
59 } 200 }
60 201
61 p = realloc (p, n); 202 p = xreallocarray (p, n, s);
62 if (!p && n) 203 *pn = n;
63 xalloc_die ();
64 return p; 204 return p;
65} 205}
66 206
67/* If P is null, allocate a block of at least *PN bytes; otherwise, 207/* Grow PA, which points to an array of *PN items, and return the
68 reallocate P so that it contains more than *PN bytes. *PN must be 208 location of the reallocated array, updating *PN to reflect its
69 nonzero unless P is null. Set *PN to the new block's size, and 209 new size. The new array will contain at least N_INCR_MIN more
70 return the pointer to the new block. *PN is never set to zero, and 210 items, but will not contain more than N_MAX items total.
71 the returned pointer is never null. */ 211 S is the size of each item, in bytes.
212
213 S and N_INCR_MIN must be positive. *PN must be
214 nonnegative. If N_MAX is -1, it is treated as if it were
215 infinity.
216
217 If PA is null, then allocate a new array instead of reallocating
218 the old one.
219
220 Thus, to grow an array A without saving its old contents, do
221 { free (A); A = xpalloc (NULL, &AITEMS, ...); }. */
72 222
73void * 223void *
74x2realloc (void *p, size_t *pn) 224xpalloc (void *pa, idx_t *pn, idx_t n_incr_min, ptrdiff_t n_max, idx_t s)
75{ 225{
76 return x2nrealloc (p, pn, 1); 226 idx_t n0 = *pn;
227
228 /* The approximate size to use for initial small allocation
229 requests. This is the largest "small" request for the GNU C
230 library malloc. */
231 enum { DEFAULT_MXFAST = 64 * sizeof (size_t) / 4 };
232
233 /* If the array is tiny, grow it to about (but no greater than)
234 DEFAULT_MXFAST bytes. Otherwise, grow it by about 50%.
235 Adjust the growth according to three constraints: N_INCR_MIN,
236 N_MAX, and what the C language can represent safely. */
237
238 idx_t n;
239 if (INT_ADD_WRAPV (n0, n0 >> 1, &n))
240 n = IDX_MAX;
241 if (0 <= n_max && n_max < n)
242 n = n_max;
243
244 /* NBYTES is of a type suitable for holding the count of bytes in an object.
245 This is typically idx_t, but it should be size_t on (theoretical?)
246 platforms where SIZE_MAX < IDX_MAX so xpalloc does not pass
247 values greater than SIZE_MAX to xrealloc. */
248#if IDX_MAX <= SIZE_MAX
249 idx_t nbytes;
250#else
251 size_t nbytes;
252#endif
253 idx_t adjusted_nbytes
254 = (INT_MULTIPLY_WRAPV (n, s, &nbytes)
255 ? MIN (IDX_MAX, SIZE_MAX)
256 : nbytes < DEFAULT_MXFAST ? DEFAULT_MXFAST : 0);
257 if (adjusted_nbytes)
258 {
259 n = adjusted_nbytes / s;
260 nbytes = adjusted_nbytes - adjusted_nbytes % s;
261 }
262
263 if (! pa)
264 *pn = 0;
265 if (n - n0 < n_incr_min
266 && (INT_ADD_WRAPV (n0, n_incr_min, &n)
267 || (0 <= n_max && n_max < n)
268 || INT_MULTIPLY_WRAPV (n, s, &nbytes)))
269 xalloc_die ();
270 pa = xrealloc (pa, nbytes);
271 *pn = n;
272 return pa;
77} 273}
78 274
79/* Allocate S bytes of zeroed memory dynamically, with error checking. 275/* Allocate S bytes of zeroed memory dynamically, with error checking.
@@ -83,7 +279,13 @@ x2realloc (void *p, size_t *pn)
83void * 279void *
84xzalloc (size_t s) 280xzalloc (size_t s)
85{ 281{
86 return memset (xmalloc (s), 0, s); 282 return xcalloc (s, 1);
283}
284
285void *
286xizalloc (idx_t s)
287{
288 return xicalloc (s, 1);
87} 289}
88 290
89/* Allocate zeroed memory for N elements of S bytes, with error 291/* Allocate zeroed memory for N elements of S bytes, with error
@@ -92,15 +294,13 @@ xzalloc (size_t s)
92void * 294void *
93xcalloc (size_t n, size_t s) 295xcalloc (size_t n, size_t s)
94{ 296{
95 void *p; 297 return nonnull (calloc (n, s));
96 /* Test for overflow, since some calloc implementations don't have 298}
97 proper overflow checks. But omit overflow and size-zero tests if 299
98 HAVE_GNU_CALLOC, since GNU calloc catches overflow and never 300void *
99 returns NULL if successful. */ 301xicalloc (idx_t n, idx_t s)
100 if ((! HAVE_GNU_CALLOC && xalloc_oversized (n, s)) 302{
101 || (! (p = calloc (n, s)) && (HAVE_GNU_CALLOC || n != 0))) 303 return nonnull (icalloc (n, s));
102 xalloc_die ();
103 return p;
104} 304}
105 305
106/* Clone an object P of size S, with error checking. There's no need 306/* Clone an object P of size S, with error checking. There's no need
@@ -113,6 +313,23 @@ xmemdup (void const *p, size_t s)
113 return memcpy (xmalloc (s), p, s); 313 return memcpy (xmalloc (s), p, s);
114} 314}
115 315
316void *
317ximemdup (void const *p, idx_t s)
318{
319 return memcpy (ximalloc (s), p, s);
320}
321
322/* Clone an object P of size S, with error checking. Append
323 a terminating NUL byte. */
324
325char *
326ximemdup0 (void const *p, idx_t s)
327{
328 char *result = ximalloc (s + 1);
329 result[s] = 0;
330 return memcpy (result, p, s);
331}
332
116/* Clone STRING. */ 333/* Clone STRING. */
117 334
118char * 335char *