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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-15 19:37:10 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-15 19:37:10 +0000 |
commit | c9addba5cc770d2d231b34f6739f32c6be8690f1 (patch) | |
tree | c643da154a95a1d163137135050bb47858a1654e /gl/lib/xmalloc.c | |
parent | Initial commit. (diff) | |
download | man-db-c9addba5cc770d2d231b34f6739f32c6be8690f1.tar.xz man-db-c9addba5cc770d2d231b34f6739f32c6be8690f1.zip |
Adding upstream version 2.12.0.upstream/2.12.0
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'gl/lib/xmalloc.c')
-rw-r--r-- | gl/lib/xmalloc.c | 340 |
1 files changed, 340 insertions, 0 deletions
diff --git a/gl/lib/xmalloc.c b/gl/lib/xmalloc.c new file mode 100644 index 0000000..289cbd0 --- /dev/null +++ b/gl/lib/xmalloc.c @@ -0,0 +1,340 @@ +/* xmalloc.c -- malloc with out of memory checking + + Copyright (C) 1990-2000, 2002-2006, 2008-2023 Free Software Foundation, Inc. + + This program is free software: you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation, either version 3 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program. If not, see <https://www.gnu.org/licenses/>. */ + +#include <config.h> + +#define XALLOC_INLINE _GL_EXTERN_INLINE + +#include "xalloc.h" + +#include "ialloc.h" +#include "minmax.h" + +#include <stdckdint.h> +#include <stdlib.h> +#include <stdint.h> +#include <string.h> + +static void * _GL_ATTRIBUTE_PURE +nonnull (void *p) +{ + if (!p) + xalloc_die (); + return p; +} + +/* Allocate S bytes of memory dynamically, with error checking. */ + +void * +xmalloc (size_t s) +{ + return nonnull (malloc (s)); +} + +void * +ximalloc (idx_t s) +{ + return nonnull (imalloc (s)); +} + +char * +xcharalloc (size_t n) +{ + return XNMALLOC (n, char); +} + +/* Change the size of an allocated block of memory P to S bytes, + with error checking. */ + +void * +xrealloc (void *p, size_t s) +{ + void *r = realloc (p, s); + if (!r && (!p || s)) + xalloc_die (); + return r; +} + +void * +xirealloc (void *p, idx_t s) +{ + return nonnull (irealloc (p, s)); +} + +/* Change the size of an allocated block of memory P to an array of N + objects each of S bytes, with error checking. */ + +void * +xreallocarray (void *p, size_t n, size_t s) +{ + void *r = reallocarray (p, n, s); + if (!r && (!p || (n && s))) + xalloc_die (); + return r; +} + +void * +xireallocarray (void *p, idx_t n, idx_t s) +{ + return nonnull (ireallocarray (p, n, s)); +} + +/* Allocate an array of N objects, each with S bytes of memory, + dynamically, with error checking. S must be nonzero. */ + +void * +xnmalloc (size_t n, size_t s) +{ + return xreallocarray (NULL, n, s); +} + +void * +xinmalloc (idx_t n, idx_t s) +{ + return xireallocarray (NULL, n, s); +} + +/* If P is null, allocate a block of at least *PS bytes; otherwise, + reallocate P so that it contains more than *PS bytes. *PS must be + nonzero unless P is null. Set *PS to the new block's size, and + return the pointer to the new block. *PS is never set to zero, and + the returned pointer is never null. */ + +void * +x2realloc (void *p, size_t *ps) +{ + return x2nrealloc (p, ps, 1); +} + +/* If P is null, allocate a block of at least *PN such objects; + otherwise, reallocate P so that it contains more than *PN objects + each of S bytes. S must be nonzero. Set *PN to the new number of + objects, and return the pointer to the new block. *PN is never set + to zero, and the returned pointer is never null. + + Repeated reallocations are guaranteed to make progress, either by + allocating an initial block with a nonzero size, or by allocating a + larger block. + + In the following implementation, nonzero sizes are increased by a + factor of approximately 1.5 so that repeated reallocations have + O(N) overall cost rather than O(N**2) cost, but the + specification for this function does not guarantee that rate. + + Here is an example of use: + + int *p = NULL; + size_t used = 0; + size_t allocated = 0; + + void + append_int (int value) + { + if (used == allocated) + p = x2nrealloc (p, &allocated, sizeof *p); + p[used++] = value; + } + + This causes x2nrealloc to allocate a block of some nonzero size the + first time it is called. + + To have finer-grained control over the initial size, set *PN to a + nonzero value before calling this function with P == NULL. For + example: + + int *p = NULL; + size_t used = 0; + size_t allocated = 0; + size_t allocated1 = 1000; + + void + append_int (int value) + { + if (used == allocated) + { + p = x2nrealloc (p, &allocated1, sizeof *p); + allocated = allocated1; + } + p[used++] = value; + } + + */ + +void * +x2nrealloc (void *p, size_t *pn, size_t s) +{ + size_t n = *pn; + + if (! p) + { + if (! n) + { + /* The approximate size to use for initial small allocation + requests, when the invoking code specifies an old size of + zero. This is the largest "small" request for the GNU C + library malloc. */ + enum { DEFAULT_MXFAST = 64 * sizeof (size_t) / 4 }; + + n = DEFAULT_MXFAST / s; + n += !n; + } + } + else + { + /* Set N = floor (1.5 * N) + 1 to make progress even if N == 0. */ + if (ckd_add (&n, n, (n >> 1) + 1)) + xalloc_die (); + } + + p = xreallocarray (p, n, s); + *pn = n; + return p; +} + +/* Grow PA, which points to an array of *PN items, and return the + location of the reallocated array, updating *PN to reflect its + new size. The new array will contain at least N_INCR_MIN more + items, but will not contain more than N_MAX items total. + S is the size of each item, in bytes. + + S and N_INCR_MIN must be positive. *PN must be + nonnegative. If N_MAX is -1, it is treated as if it were + infinity. + + If PA is null, then allocate a new array instead of reallocating + the old one. + + Thus, to grow an array A without saving its old contents, do + { free (A); A = xpalloc (NULL, &AITEMS, ...); }. */ + +void * +xpalloc (void *pa, idx_t *pn, idx_t n_incr_min, ptrdiff_t n_max, idx_t s) +{ + idx_t n0 = *pn; + + /* The approximate size to use for initial small allocation + requests. This is the largest "small" request for the GNU C + library malloc. */ + enum { DEFAULT_MXFAST = 64 * sizeof (size_t) / 4 }; + + /* If the array is tiny, grow it to about (but no greater than) + DEFAULT_MXFAST bytes. Otherwise, grow it by about 50%. + Adjust the growth according to three constraints: N_INCR_MIN, + N_MAX, and what the C language can represent safely. */ + + idx_t n; + if (ckd_add (&n, n0, n0 >> 1)) + n = IDX_MAX; + if (0 <= n_max && n_max < n) + n = n_max; + + /* NBYTES is of a type suitable for holding the count of bytes in an object. + This is typically idx_t, but it should be size_t on (theoretical?) + platforms where SIZE_MAX < IDX_MAX so xpalloc does not pass + values greater than SIZE_MAX to xrealloc. */ +#if IDX_MAX <= SIZE_MAX + idx_t nbytes; +#else + size_t nbytes; +#endif + idx_t adjusted_nbytes + = (ckd_mul (&nbytes, n, s) + ? MIN (IDX_MAX, SIZE_MAX) + : nbytes < DEFAULT_MXFAST ? DEFAULT_MXFAST : 0); + if (adjusted_nbytes) + { + n = adjusted_nbytes / s; + nbytes = adjusted_nbytes - adjusted_nbytes % s; + } + + if (! pa) + *pn = 0; + if (n - n0 < n_incr_min + && (ckd_add (&n, n0, n_incr_min) + || (0 <= n_max && n_max < n) + || ckd_mul (&nbytes, n, s))) + xalloc_die (); + pa = xrealloc (pa, nbytes); + *pn = n; + return pa; +} + +/* Allocate S bytes of zeroed memory dynamically, with error checking. + There's no need for xnzalloc (N, S), since it would be equivalent + to xcalloc (N, S). */ + +void * +xzalloc (size_t s) +{ + return xcalloc (s, 1); +} + +void * +xizalloc (idx_t s) +{ + return xicalloc (s, 1); +} + +/* Allocate zeroed memory for N elements of S bytes, with error + checking. S must be nonzero. */ + +void * +xcalloc (size_t n, size_t s) +{ + return nonnull (calloc (n, s)); +} + +void * +xicalloc (idx_t n, idx_t s) +{ + return nonnull (icalloc (n, s)); +} + +/* Clone an object P of size S, with error checking. There's no need + for xnmemdup (P, N, S), since xmemdup (P, N * S) works without any + need for an arithmetic overflow check. */ + +void * +xmemdup (void const *p, size_t s) +{ + return memcpy (xmalloc (s), p, s); +} + +void * +ximemdup (void const *p, idx_t s) +{ + return memcpy (ximalloc (s), p, s); +} + +/* Clone an object P of size S, with error checking. Append + a terminating NUL byte. */ + +char * +ximemdup0 (void const *p, idx_t s) +{ + char *result = ximalloc (s + 1); + result[s] = 0; + return memcpy (result, p, s); +} + +/* Clone STRING. */ + +char * +xstrdup (char const *string) +{ + return xmemdup (string, strlen (string) + 1); +} |