1 /*************************************************
2 * Perl-Compatible Regular Expressions *
3 *************************************************/
4
5 /* PCRE is a library of functions to support regular expressions whose syntax
6 and semantics are as close as possible to those of the Perl 5 language.
7
8 Written by Philip Hazel
9 Copyright (c) 2023 University of Cambridge
10
11 -----------------------------------------------------------------------------
12 Redistribution and use in source and binary forms, with or without
13 modification, are permitted provided that the following conditions are met:
14
15 * Redistributions of source code must retain the above copyright notice,
16 this list of conditions and the following disclaimer.
17
18 * Redistributions in binary form must reproduce the above copyright
19 notice, this list of conditions and the following disclaimer in the
20 documentation and/or other materials provided with the distribution.
21
22 * Neither the name of the University of Cambridge nor the names of its
23 contributors may be used to endorse or promote products derived from
24 this software without specific prior written permission.
25
26 THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
27 AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
28 IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
29 ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
30 LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
31 CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
32 SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
33 INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
34 CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
35 ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
36 POSSIBILITY OF SUCH DAMAGE.
37 -----------------------------------------------------------------------------
38 */
39
40 /* This file contains functions to implement checked integer operation */
41
42 #ifndef PCRE2_PCRE2TEST
43 #ifdef HAVE_CONFIG_H
44 #include "config.h"
45 #endif
46
47 #include "pcre2_internal.h"
48 #endif
49
50 /*************************************************
51 * Checked Integer Multiplication *
52 *************************************************/
53
54 /*
55 Arguments:
56 r A pointer to PCRE2_SIZE to store the answer
57 a, b Two integers
58
59 Returns: Bool indicating if the operation overflows
60
61 It is modeled after C23's <stdckdint.h> interface
62 The INT64_OR_DOUBLE type is a 64-bit integer type when available,
63 otherwise double. */
64
65 BOOL
PRIV(ckd_smul)66 PRIV(ckd_smul)(PCRE2_SIZE *r, int a, int b)
67 {
68 #ifdef HAVE_BUILTIN_MUL_OVERFLOW
69 PCRE2_SIZE m;
70
71 if (__builtin_mul_overflow(a, b, &m)) return TRUE;
72
73 *r = m;
74 #else
75 INT64_OR_DOUBLE m;
76
77 #ifdef PCRE2_DEBUG
78 if (a < 0 || b < 0) abort();
79 #endif
80
81 m = (INT64_OR_DOUBLE)a * (INT64_OR_DOUBLE)b;
82
83 #if defined INT64_MAX || defined int64_t
84 if (sizeof(m) > sizeof(*r) && m > (INT64_OR_DOUBLE)PCRE2_SIZE_MAX) return TRUE;
85 *r = (PCRE2_SIZE)m;
86 #else
87 if (m > PCRE2_SIZE_MAX) return TRUE;
88 *r = m;
89 #endif
90
91 #endif
92
93 return FALSE;
94 }
95
96 /* End of pcre_chkdint.c */
97
