1 /* init.c: bcmath library file. */
2 /*
3 Copyright (C) 1991, 1992, 1993, 1994, 1997 Free Software Foundation, Inc.
4 Copyright (C) 2000 Philip A. Nelson
5
6 This library is free software; you can redistribute it and/or
7 modify it under the terms of the GNU Lesser General Public
8 License as published by the Free Software Foundation; either
9 version 2 of the License, or (at your option) any later version.
10
11 This library is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 Lesser General Public License for more details. (LICENSE)
15
16 You should have received a copy of the GNU Lesser General Public
17 License along with this library; if not, write to:
18
19 The Free Software Foundation, Inc.
20 59 Temple Place, Suite 330
21 Boston, MA 02111-1307 USA.
22
23 You may contact the author by:
24 e-mail: philnelson@acm.org
25 us-mail: Philip A. Nelson
26 Computer Science Department, 9062
27 Western Washington University
28 Bellingham, WA 98226-9062
29
30 *************************************************************************/
31
32 #include "bcmath.h"
33 #include <stdbool.h>
34 #include <stddef.h>
35 #include <string.h>
36 #include "zend_alloc.h"
37
_bc_new_num_nonzeroed_ex_internal(size_t length,size_t scale,bool persistent)38 static bc_num _bc_new_num_nonzeroed_ex_internal(size_t length, size_t scale, bool persistent)
39 {
40 size_t required_size = zend_safe_address_guarded(1, sizeof(bc_struct) + (ZEND_MM_ALIGNMENT - 1) + length, scale);
41 required_size &= -ZEND_MM_ALIGNMENT;
42 bc_num temp;
43
44 if (!persistent && BCG(arena) && required_size <= BC_ARENA_SIZE - BCG(arena_offset)) {
45 temp = (bc_num) (BCG(arena) + BCG(arena_offset));
46 BCG(arena_offset) += required_size;
47 temp->n_refs = 2; /* prevent freeing */
48 } else {
49 /* PHP Change: malloc() -> pemalloc(), removed free_list code, merged n_ptr and n_value */
50 temp = pemalloc(required_size, persistent);
51 temp->n_refs = 1;
52 }
53
54 temp->n_sign = PLUS;
55 temp->n_len = length;
56 temp->n_scale = scale;
57 temp->n_value = (char *) temp + sizeof(bc_struct);
58 return temp;
59 }
60
61 /* new_num allocates a number and sets fields to known values. */
_bc_new_num_ex(size_t length,size_t scale,bool persistent)62 bc_num _bc_new_num_ex(size_t length, size_t scale, bool persistent)
63 {
64 bc_num temp = _bc_new_num_nonzeroed_ex_internal(length, scale, persistent);
65 memset(temp->n_value, 0, length + scale);
66 return temp;
67 }
68
_bc_new_num_nonzeroed_ex(size_t length,size_t scale,bool persistent)69 bc_num _bc_new_num_nonzeroed_ex(size_t length, size_t scale, bool persistent)
70 {
71 return _bc_new_num_nonzeroed_ex_internal(length, scale, persistent);
72 }
73
74 /* "Frees" a bc_num NUM. Actually decreases reference count and only
75 frees the storage if reference count is zero. */
_bc_free_num_ex(bc_num * num,bool persistent)76 void _bc_free_num_ex(bc_num *num, bool persistent)
77 {
78 if (*num == NULL) {
79 return;
80 }
81 (*num)->n_refs--;
82 if ((*num)->n_refs == 0) {
83 pefree(*num, persistent);
84 }
85 *num = NULL;
86 }
87
88
89 /* Initialize the number package! */
90
bc_init_numbers(void)91 void bc_init_numbers(void)
92 {
93 BCG(_zero_) = _bc_new_num_ex(1, 0, 1);
94 BCG(_one_) = _bc_new_num_ex(1, 0, 1);
95 BCG(_one_)->n_value[0] = 1;
96 BCG(_two_) = _bc_new_num_ex(1, 0, 1);
97 BCG(_two_)->n_value[0] = 2;
98 }
99
100
101 /* Initialize a number NUM by making it a copy of zero. */
bc_init_num(bc_num * num)102 void bc_init_num(bc_num *num)
103 {
104 *num = bc_copy_num(BCG(_zero_));
105 }
106