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8.33

    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) 1997-2012 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: #if defined COMPILE_PCRE8
   83: PCRE_EXP_DEFN const char * PCRE_CALL_CONVENTION
   84: pcre_version(void)
   85: #elif defined COMPILE_PCRE16
   86: PCRE_EXP_DEFN const char * PCRE_CALL_CONVENTION
   87: pcre16_version(void)
   88: #elif defined COMPILE_PCRE32
   89: PCRE_EXP_DEFN const char * PCRE_CALL_CONVENTION
   90: pcre32_version(void)
   91: #endif
   92: {
   93: return (XSTRING(Z PCRE_PRERELEASE)[1] == 0)?
   94:   XSTRING(PCRE_MAJOR.PCRE_MINOR PCRE_DATE) :
   95:   XSTRING(PCRE_MAJOR.PCRE_MINOR) XSTRING(PCRE_PRERELEASE PCRE_DATE);
   96: }
   97: 
   98: /* End of pcre_version.c */