1/*************************************************
2* Perl-Compatible Regular Expressions *
3*************************************************/
4
5/* PCRE is a library of functions to support regular expressions whose syntax
6and semantics are as close as possible to those of the Perl 5 language.
7
8 Written by Philip Hazel
9 Copyright (c) 1997-2012 University of Cambridge
10
11-----------------------------------------------------------------------------
12Redistribution and use in source and binary forms, with or without
13modification, 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
26THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
27AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
28IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
29ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
30LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
31CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
32SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
33INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
34CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
35ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
36POSSIBILITY OF SUCH DAMAGE.
37-----------------------------------------------------------------------------
38*/
39
40#pragma warning( disable : 4244) // conversion from 'int' to 'unsigned short', possible loss of data
41
42/* This module contains the external function pcre_refcount(), which is an
43auxiliary function that can be used to maintain a reference count in a compiled
44pattern data block. This might be helpful in applications where the block is
45shared by different users. */
46
47
48#include "pcre_config.h"
49#include "pcre_internal.h"
50
51
52/*************************************************
53* Maintain reference count *
54*************************************************/
55
56/* The reference count is a 16-bit field, initialized to zero. It is not
57possible to transfer a non-zero count from one host to a different host that
58has a different byte order - though I can't see why anyone in their right mind
59would ever want to do that!
60
61Arguments:
62 argument_re points to compiled code
63 adjust value to add to the count
64
65Returns: the (possibly updated) count value (a non-negative number), or
66 a negative error number
67*/
68
69#if defined COMPILE_PCRE8
70PCRE_EXP_DEFN int PCRE_CALL_CONVENTION
71pcre_refcount(pcre *argument_re, int adjust)
72#elif defined COMPILE_PCRE16
73PCRE_EXP_DEFN int PCRE_CALL_CONVENTION
74pcre16_refcount(pcre16 *argument_re, int adjust)
75#elif defined COMPILE_PCRE32
76PCRE_EXP_DEFN int PCRE_CALL_CONVENTION
77pcre32_refcount(pcre32 *argument_re, int adjust)
78#endif
79{
80REAL_PCRE *re = (REAL_PCRE *)argument_re;
81if (re == NULL) return PCRE_ERROR_NULL;
82if (re->magic_number != MAGIC_NUMBER) return PCRE_ERROR_BADMAGIC;
83if ((re->flags & PCRE_MODE) == 0) return PCRE_ERROR_BADMODE;
84re->ref_count = (-adjust > re->ref_count)? 0 :
85 (adjust + re->ref_count > 65535)? 65535 :
86 re->ref_count + adjust;
87return re->ref_count;
88}
89
90/* End of pcre_refcount.c */
91