Tristan Matthews | 0461646 | 2013-11-14 16:09:34 -0500 | [diff] [blame] | 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) 1997-2008 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 | |
| 41 | /* This module contains the external function pcre_version(), which returns a |
| 42 | string that identifies the PCRE version that is in use. */ |
| 43 | |
| 44 | |
| 45 | #ifdef HAVE_CONFIG_H |
| 46 | #include "config.h" |
| 47 | #endif |
| 48 | |
| 49 | #include "pcre_internal.h" |
| 50 | |
| 51 | |
| 52 | /************************************************* |
| 53 | * Return version string * |
| 54 | *************************************************/ |
| 55 | |
| 56 | /* These macros are the standard way of turning unquoted text into C strings. |
| 57 | They allow macros like PCRE_MAJOR to be defined without quotes, which is |
| 58 | convenient for user programs that want to test its value. */ |
| 59 | |
| 60 | #define STRING(a) # a |
| 61 | #define XSTRING(s) STRING(s) |
| 62 | |
| 63 | /* A problem turned up with PCRE_PRERELEASE, which is defined empty for |
| 64 | production releases. Originally, it was used naively in this code: |
| 65 | |
| 66 | return XSTRING(PCRE_MAJOR) |
| 67 | "." XSTRING(PCRE_MINOR) |
| 68 | XSTRING(PCRE_PRERELEASE) |
| 69 | " " XSTRING(PCRE_DATE); |
| 70 | |
| 71 | However, when PCRE_PRERELEASE is empty, this leads to an attempted expansion of |
| 72 | STRING(). The C standard states: "If (before argument substitution) any |
| 73 | argument consists of no preprocessing tokens, the behavior is undefined." It |
| 74 | turns out the gcc treats this case as a single empty string - which is what we |
| 75 | really want - but Visual C grumbles about the lack of an argument for the |
| 76 | macro. Unfortunately, both are within their rights. To cope with both ways of |
| 77 | handling this, I had resort to some messy hackery that does a test at run time. |
| 78 | I could find no way of detecting that a macro is defined as an empty string at |
| 79 | pre-processor time. This hack uses a standard trick for avoiding calling |
| 80 | the STRING macro with an empty argument when doing the test. */ |
| 81 | |
| 82 | PCRE_EXP_DEFN const char * PCRE_CALL_CONVENTION |
| 83 | pcre_version(void) |
| 84 | { |
| 85 | return (XSTRING(Z PCRE_PRERELEASE)[1] == 0)? |
| 86 | XSTRING(PCRE_MAJOR.PCRE_MINOR PCRE_DATE) : |
| 87 | XSTRING(PCRE_MAJOR.PCRE_MINOR) XSTRING(PCRE_PRERELEASE PCRE_DATE); |
| 88 | } |
| 89 | |
| 90 | /* End of pcre_version.c */ |