Update POSIX wrapper to use macros in the .h file, but also have the POSIX
function names in the library.
This commit is contained in:
parent
51fb3956ee
commit
ae913fbee7
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@ -14,9 +14,12 @@ a greater than 1 fixed quantifier. This issue was found by Yunho Kim.
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3. Added support for callouts from pcre2_substitute().
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4. The POSIX functions are now all called pcre2_regcomp() etc., with wrappers
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that use the standard POSIX names. This should help avoid linking with the
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wrong library in some environments.
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4. The POSIX functions are now all called pcre2_regcomp() etc., with wrapper
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functions that use the standard POSIX names. However, in pcre2posix.h the POSIX
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names are defined as macros. This should help avoid linking with the wrong
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library in some environments while still exporting the POSIX names for
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pre-existing programs that use them. (The Debian alternative names are also
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defined as macros, but not documented.)
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5. Fix an xclass matching issue in JIT.
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17
README
17
README
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@ -53,19 +53,8 @@ The header file for the POSIX-style functions is called pcre2posix.h. The
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official POSIX name is regex.h, but I did not want to risk possible problems
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with existing files of that name by distributing it that way. To use PCRE2 with
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an existing program that uses the POSIX API, pcre2posix.h will have to be
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renamed or pointed at by a link (or the program modified, of course).
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If you are using the POSIX interface to PCRE2 and there is already a POSIX
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regex library installed on your system, as well as worrying about the regex.h
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header file (as mentioned above), you must also take care when linking programs
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to ensure that they link with PCRE2's libpcre2-posix library. Otherwise they
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may pick up the POSIX functions of the same name from the other library.
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To help with this issue, the libpcre2-posix library provides alternative names
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for the POSIX functions. These are the POSIX names, prefixed with "pcre2_", for
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example, pcre2_regcomp(). If an application can be compiled to use the
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alternative names (for example by the use of -Dregcomp=pcre2_regcomp etc.) it
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can be sure of linking with the PCRE2 functions.
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renamed or pointed at by a link (or the program modified, of course). See the
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pcre2posix documentation for more details.
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Documentation for PCRE2
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@ -897,4 +886,4 @@ The distribution should contain the files listed below.
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Philip Hazel
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Email local part: ph10
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Email domain: cam.ac.uk
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Last updated: 15 November 2018
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Last updated: 29 January 2019
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@ -53,19 +53,8 @@ The header file for the POSIX-style functions is called pcre2posix.h. The
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official POSIX name is regex.h, but I did not want to risk possible problems
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with existing files of that name by distributing it that way. To use PCRE2 with
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an existing program that uses the POSIX API, pcre2posix.h will have to be
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renamed or pointed at by a link (or the program modified, of course).
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If you are using the POSIX interface to PCRE2 and there is already a POSIX
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regex library installed on your system, as well as worrying about the regex.h
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header file (as mentioned above), you must also take care when linking programs
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to ensure that they link with PCRE2's libpcre2-posix library. Otherwise they
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may pick up the POSIX functions of the same name from the other library.
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To help with this issue, the libpcre2-posix library provides alternative names
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for the POSIX functions. These are the POSIX names, prefixed with "pcre2_", for
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example, pcre2_regcomp(). If an application can be compiled to use the
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alternative names (for example by the use of -Dregcomp=pcre2_regcomp etc.) it
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can be sure of linking with the PCRE2 functions.
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renamed or pointed at by a link (or the program modified, of course). See the
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pcre2posix documentation for more details.
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Documentation for PCRE2
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@ -897,4 +886,4 @@ The distribution should contain the files listed below.
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Philip Hazel
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Email local part: ph10
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Email domain: cam.ac.uk
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Last updated: 15 November 2018
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Last updated: 29 January 2019
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@ -15,74 +15,75 @@ please consult the man page, in case the conversion went wrong.
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<ul>
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<li><a name="TOC1" href="#SEC1">SYNOPSIS</a>
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<li><a name="TOC2" href="#SEC2">DESCRIPTION</a>
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<li><a name="TOC3" href="#SEC3">COMPILING A PATTERN</a>
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<li><a name="TOC4" href="#SEC4">MATCHING NEWLINE CHARACTERS</a>
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<li><a name="TOC5" href="#SEC5">MATCHING A PATTERN</a>
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<li><a name="TOC6" href="#SEC6">ERROR MESSAGES</a>
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<li><a name="TOC7" href="#SEC7">MEMORY USAGE</a>
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<li><a name="TOC8" href="#SEC8">AUTHOR</a>
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<li><a name="TOC9" href="#SEC9">REVISION</a>
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<li><a name="TOC3" href="#SEC3">USING THE POSIX FUNCTIONS</a>
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<li><a name="TOC4" href="#SEC4">COMPILING A PATTERN</a>
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<li><a name="TOC5" href="#SEC5">MATCHING NEWLINE CHARACTERS</a>
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<li><a name="TOC6" href="#SEC6">MATCHING A PATTERN</a>
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<li><a name="TOC7" href="#SEC7">ERROR MESSAGES</a>
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<li><a name="TOC8" href="#SEC8">MEMORY USAGE</a>
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<li><a name="TOC9" href="#SEC9">AUTHOR</a>
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<li><a name="TOC10" href="#SEC10">REVISION</a>
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</ul>
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<br><a name="SEC1" href="#TOC1">SYNOPSIS</a><br>
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<P>
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<b>#include <pcre2posix.h></b>
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</P>
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<P>
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<b>int regcomp(regex_t *<i>preg</i>, const char *<i>pattern</i>,</b>
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<b> int <i>cflags</i>);</b>
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<br>
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<br>
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<b>int pcre2_regcomp(regex_t *<i>preg</i>, const char *<i>pattern</i>,</b>
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<b> int <i>cflags</i>);</b>
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<br>
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<br>
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<b>int regexec(const regex_t *<i>preg</i>, const char *<i>string</i>,</b>
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<b> size_t <i>nmatch</i>, regmatch_t <i>pmatch</i>[], int <i>eflags</i>);</b>
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<br>
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<br>
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<b>int pcre2_regexec(const regex_t *<i>preg</i>, const char *<i>string</i>,</b>
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<b> size_t <i>nmatch</i>, regmatch_t <i>pmatch</i>[], int <i>eflags</i>);</b>
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<br>
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<br>
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<b>size_t regerror(int <i>errcode</i>, const regex_t *<i>preg</i>,</b>
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<b> char *<i>errbuf</i>, size_t <i>errbuf_size</i>);</b>
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<br>
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<br>
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<b>size_t pcre2_regerror(int <i>errcode</i>, const regex_t *<i>preg</i>,</b>
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<b> char *<i>errbuf</i>, size_t <i>errbuf_size</i>);</b>
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<br>
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<br>
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<b>void regfree(regex_t *<i>preg</i>);</b>
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<br>
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<br>
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<b>void pcre2_regfree(regex_t *<i>preg</i>);</b>
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</P>
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<br><a name="SEC2" href="#TOC1">DESCRIPTION</a><br>
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<P>
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This set of functions provides a POSIX-style API for the PCRE2 regular
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expression 8-bit library. See the
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expression 8-bit library. There are no POSIX-style wrappers for PCRE2's 16-bit
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and 32-bit libraries. See the
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<a href="pcre2api.html"><b>pcre2api</b></a>
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documentation for a description of PCRE2's native API, which contains much
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additional functionality. There are no POSIX-style wrappers for PCRE2's 16-bit
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and 32-bit libraries.
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additional functionality.
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</P>
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<P>
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The functions described here are just wrapper functions that ultimately call
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the PCRE2 native API. Their prototypes are defined in the <b>pcre2posix.h</b>
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header file, and on Unix systems the library itself is called
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<b>libpcre2-posix.a</b>, so can be accessed by adding <b>-lpcre2-posix</b> to the
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command for linking an application that uses them. Because the POSIX functions
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call the native ones, it is also necessary to add <b>-lpcre2-8</b>.
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The functions described here are wrapper functions that ultimately call the
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PCRE2 native API. Their prototypes are defined in the <b>pcre2posix.h</b> header
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file, and they all have unique names starting with <b>pcre2_</b>. However, the
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<b>pcre2posix.h</b> header also contains macro definitions that convert the
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standard POSIX names such <b>regcomp()</b> into <b>pcre2_regcomp()</b> etc. This
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means that a program can use the usual POSIX names without running the risk of
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accidentally linking with POSIX functions from a different library.
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</P>
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<P>
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When another POSIX regex library is also installed, there is the possibility of
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linking an application with the wrong library. To help avoid this issue, the
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PCRE2 POSIX library provides alternative names for the functions, all starting
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with "pcre2_". If an application uses these names, possible ambiguity is
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avoided. In the following description, however, the standard POSIX function
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names are used.
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On Unix-like systems the PCRE2 POSIX library is called <b>libpcre2-posix</b>, so
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can be accessed by adding <b>-lpcre2-posix</b> to the command for linking an
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application. Because the POSIX functions call the native ones, it is also
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necessary to add <b>-lpcre2-8</b>.
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</P>
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<P>
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Although they are not defined as protypes in <b>pcre2posix.h</b>, the library
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does contain functions with the POSIX names <b>regcomp()</b> etc. These simply
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pass their arguments to the PCRE2 functions. These functions are provided for
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backwards compatibility with earlier versions of PCRE2, so that existing
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programs do not have to be recompiled.
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</P>
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<P>
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Calling the header file <b>pcre2posix.h</b> avoids any conflict with other POSIX
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libraries. It can, of course, be renamed or aliased as <b>regex.h</b>, which is
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the "correct" name, if there is no clash. It provides two structure types,
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<i>regex_t</i> for compiled internal forms, and <i>regmatch_t</i> for returning
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captured substrings. It also defines some constants whose names start with
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"REG_"; these are used for setting options and identifying error codes.
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</P>
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<br><a name="SEC3" href="#TOC1">USING THE POSIX FUNCTIONS</a><br>
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<P>
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Those POSIX option bits that can reasonably be mapped to PCRE2 native options
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have been implemented. In addition, the option REG_EXTENDED is defined with the
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value zero. This has no effect, but since programs that are written to the
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@ -103,17 +104,13 @@ POSIX definition; it is not fully POSIX-compatible, and in multi-unit encoding
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domains it is probably even less compatible.
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</P>
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<P>
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The header for these functions is supplied as <b>pcre2posix.h</b> to avoid any
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potential clash with other POSIX libraries. It can, of course, be renamed or
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aliased as <b>regex.h</b>, which is the "correct" name. It provides two
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structure types, <i>regex_t</i> for compiled internal forms, and
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<i>regmatch_t</i> for returning captured substrings. It also defines some
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constants whose names start with "REG_"; these are used for setting options and
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identifying error codes.
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The descriptions below use the actual names of the functions, but, as described
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above, the standard POSIX names (without the <b>pcre2_</b> prefix) may also be
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used.
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</P>
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<br><a name="SEC3" href="#TOC1">COMPILING A PATTERN</a><br>
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<br><a name="SEC4" href="#TOC1">COMPILING A PATTERN</a><br>
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<P>
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The function <b>regcomp()</b> is called to compile a pattern into an
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The function <b>pcre2_regcomp()</b> is called to compile a pattern into an
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internal form. By default, the pattern is a C string terminated by a binary
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zero (but see REG_PEND below). The <i>preg</i> argument is a pointer to a
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<b>regex_t</b> structure that is used as a base for storing information about
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@ -151,18 +148,18 @@ REG_UTF. Note that REG_NOSPEC is not part of the POSIX standard.
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<pre>
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REG_NOSUB
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</pre>
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When a pattern that is compiled with this flag is passed to <b>regexec()</b> for
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matching, the <i>nmatch</i> and <i>pmatch</i> arguments are ignored, and no
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captured strings are returned. Versions of the PCRE library prior to 10.22 used
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to set the PCRE2_NO_AUTO_CAPTURE compile option, but this no longer happens
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because it disables the use of backreferences.
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When a pattern that is compiled with this flag is passed to
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<b>pcre2_regexec()</b> for matching, the <i>nmatch</i> and <i>pmatch</i> arguments
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are ignored, and no captured strings are returned. Versions of the PCRE library
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prior to 10.22 used to set the PCRE2_NO_AUTO_CAPTURE compile option, but this
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no longer happens because it disables the use of backreferences.
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<pre>
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REG_PEND
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</pre>
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If this option is set, the <b>reg_endp</b> field in the <i>preg</i> structure
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(which has the type const char *) must be set to point to the character beyond
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the end of the pattern before calling <b>regcomp()</b>. The pattern itself may
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now contain binary zeros, which are treated as data characters. Without
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the end of the pattern before calling <b>pcre2_regcomp()</b>. The pattern itself
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may now contain binary zeros, which are treated as data characters. Without
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REG_PEND, a binary zero terminates the pattern and the <b>re_endp</b> field is
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ignored. This is a GNU extension to the POSIX standard and should be used with
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caution in software intended to be portable to other systems.
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@ -197,18 +194,19 @@ newlines are matched by the dot metacharacter (they are not) or by a negative
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class such as [^a] (they are).
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</P>
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<P>
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The yield of <b>regcomp()</b> is zero on success, and non-zero otherwise. The
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<i>preg</i> structure is filled in on success, and one other member of the
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The yield of <b>pcre2_regcomp()</b> is zero on success, and non-zero otherwise.
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The <i>preg</i> structure is filled in on success, and one other member of the
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structure (as well as <i>re_endp</i>) is public: <i>re_nsub</i> contains the
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number of capturing subpatterns in the regular expression. Various error codes
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are defined in the header file.
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</P>
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<P>
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NOTE: If the yield of <b>regcomp()</b> is non-zero, you must not attempt to
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use the contents of the <i>preg</i> structure. If, for example, you pass it to
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<b>regexec()</b>, the result is undefined and your program is likely to crash.
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NOTE: If the yield of <b>pcre2_regcomp()</b> is non-zero, you must not attempt
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to use the contents of the <i>preg</i> structure. If, for example, you pass it
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to <b>pcre2_regexec()</b>, the result is undefined and your program is likely to
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crash.
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</P>
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<br><a name="SEC4" href="#TOC1">MATCHING NEWLINE CHARACTERS</a><br>
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<br><a name="SEC5" href="#TOC1">MATCHING NEWLINE CHARACTERS</a><br>
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<P>
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This area is not simple, because POSIX and Perl take different views of things.
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It is not possible to get PCRE2 to obey POSIX semantics, but then PCRE2 was
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@ -242,16 +240,16 @@ is no way to stop newline from matching [^a].
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Default POSIX newline handling can be obtained by setting PCRE2_DOTALL and
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PCRE2_DOLLAR_ENDONLY when calling <b>pcre2_compile()</b> directly, but there is
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no way to make PCRE2 behave exactly as for the REG_NEWLINE action. When using
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the POSIX API, passing REG_NEWLINE to PCRE2's <b>regcomp()</b> function
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the POSIX API, passing REG_NEWLINE to PCRE2's <b>pcre2_regcomp()</b> function
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causes PCRE2_MULTILINE to be passed to <b>pcre2_compile()</b>, and REG_DOTALL
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passes PCRE2_DOTALL. There is no way to pass PCRE2_DOLLAR_ENDONLY.
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</P>
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<br><a name="SEC5" href="#TOC1">MATCHING A PATTERN</a><br>
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<br><a name="SEC6" href="#TOC1">MATCHING A PATTERN</a><br>
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<P>
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The function <b>regexec()</b> is called to match a compiled pattern <i>preg</i>
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against a given <i>string</i>, which is by default terminated by a zero byte
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(but see REG_STARTEND below), subject to the options in <i>eflags</i>. These can
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be:
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The function <b>pcre2_regexec()</b> is called to match a compiled pattern
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<i>preg</i> against a given <i>string</i>, which is by default terminated by a
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zero byte (but see REG_STARTEND below), subject to the options in <i>eflags</i>.
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These can be:
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<pre>
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REG_NOTBOL
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</pre>
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@ -295,7 +293,7 @@ are mutually exclusive; the error REG_INVARG is returned.
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<P>
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If the pattern was compiled with the REG_NOSUB flag, no data about any matched
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strings is returned. The <i>nmatch</i> and <i>pmatch</i> arguments of
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<b>regexec()</b> are ignored (except possibly as input for REG_STARTEND).
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<b>pcre2_regexec()</b> are ignored (except possibly as input for REG_STARTEND).
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</P>
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<P>
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The value of <i>nmatch</i> may be zero, and the value <i>pmatch</i> may be NULL
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@ -317,24 +315,25 @@ array have both structure members set to -1.
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A successful match yields a zero return; various error codes are defined in the
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header file, of which REG_NOMATCH is the "expected" failure code.
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</P>
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<br><a name="SEC6" href="#TOC1">ERROR MESSAGES</a><br>
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<br><a name="SEC7" href="#TOC1">ERROR MESSAGES</a><br>
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<P>
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The <b>regerror()</b> function maps a non-zero errorcode from either
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<b>regcomp()</b> or <b>regexec()</b> to a printable message. If <i>preg</i> is not
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NULL, the error should have arisen from the use of that structure. A message
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terminated by a binary zero is placed in <i>errbuf</i>. If the buffer is too
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short, only the first <i>errbuf_size</i> - 1 characters of the error message are
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used. The yield of the function is the size of buffer needed to hold the whole
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message, including the terminating zero. This value is greater than
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<i>errbuf_size</i> if the message was truncated.
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The <b>pcre2_regerror()</b> function maps a non-zero errorcode from either
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<b>pcre2_regcomp()</b> or <b>pcre2_regexec()</b> to a printable message. If
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<i>preg</i> is not NULL, the error should have arisen from the use of that
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structure. A message terminated by a binary zero is placed in <i>errbuf</i>. If
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the buffer is too short, only the first <i>errbuf_size</i> - 1 characters of the
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error message are used. The yield of the function is the size of buffer needed
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to hold the whole message, including the terminating zero. This value is
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greater than <i>errbuf_size</i> if the message was truncated.
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</P>
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<br><a name="SEC7" href="#TOC1">MEMORY USAGE</a><br>
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<br><a name="SEC8" href="#TOC1">MEMORY USAGE</a><br>
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<P>
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Compiling a regular expression causes memory to be allocated and associated
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with the <i>preg</i> structure. The function <b>regfree()</b> frees all such
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memory, after which <i>preg</i> may no longer be used as a compiled expression.
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with the <i>preg</i> structure. The function <b>pcre2_regfree()</b> frees all
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such memory, after which <i>preg</i> may no longer be used as a compiled
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expression.
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</P>
|
||||
<br><a name="SEC8" href="#TOC1">AUTHOR</a><br>
|
||||
<br><a name="SEC9" href="#TOC1">AUTHOR</a><br>
|
||||
<P>
|
||||
Philip Hazel
|
||||
<br>
|
||||
|
@ -343,11 +342,11 @@ University Computing Service
|
|||
Cambridge, England.
|
||||
<br>
|
||||
</P>
|
||||
<br><a name="SEC9" href="#TOC1">REVISION</a><br>
|
||||
<br><a name="SEC10" href="#TOC1">REVISION</a><br>
|
||||
<P>
|
||||
Last updated: 19 September 2018
|
||||
Last updated: 30 January 2019
|
||||
<br>
|
||||
Copyright © 1997-2018 University of Cambridge.
|
||||
Copyright © 1997-2019 University of Cambridge.
|
||||
<br>
|
||||
<p>
|
||||
Return to the <a href="index.html">PCRE2 index page</a>.
|
||||
|
|
257
doc/pcre2.txt
257
doc/pcre2.txt
|
@ -9587,175 +9587,179 @@ SYNOPSIS
|
|||
|
||||
#include <pcre2posix.h>
|
||||
|
||||
int regcomp(regex_t *preg, const char *pattern,
|
||||
int cflags);
|
||||
|
||||
int pcre2_regcomp(regex_t *preg, const char *pattern,
|
||||
int cflags);
|
||||
|
||||
int regexec(const regex_t *preg, const char *string,
|
||||
size_t nmatch, regmatch_t pmatch[], int eflags);
|
||||
|
||||
int pcre2_regexec(const regex_t *preg, const char *string,
|
||||
size_t nmatch, regmatch_t pmatch[], int eflags);
|
||||
|
||||
size_t regerror(int errcode, const regex_t *preg,
|
||||
char *errbuf, size_t errbuf_size);
|
||||
|
||||
size_t pcre2_regerror(int errcode, const regex_t *preg,
|
||||
char *errbuf, size_t errbuf_size);
|
||||
|
||||
void regfree(regex_t *preg);
|
||||
|
||||
void pcre2_regfree(regex_t *preg);
|
||||
|
||||
|
||||
DESCRIPTION
|
||||
|
||||
This set of functions provides a POSIX-style API for the PCRE2 regular
|
||||
expression 8-bit library. See the pcre2api documentation for a descrip-
|
||||
tion of PCRE2's native API, which contains much additional functional-
|
||||
ity. There are no POSIX-style wrappers for PCRE2's 16-bit and 32-bit
|
||||
libraries.
|
||||
expression 8-bit library. There are no POSIX-style wrappers for PCRE2's
|
||||
16-bit and 32-bit libraries. See the pcre2api documentation for a
|
||||
description of PCRE2's native API, which contains much additional func-
|
||||
tionality.
|
||||
|
||||
The functions described here are just wrapper functions that ultimately
|
||||
call the PCRE2 native API. Their prototypes are defined in the
|
||||
pcre2posix.h header file, and on Unix systems the library itself is
|
||||
called libpcre2-posix.a, so can be accessed by adding -lpcre2-posix to
|
||||
the command for linking an application that uses them. Because the
|
||||
POSIX functions call the native ones, it is also necessary to add
|
||||
-lpcre2-8.
|
||||
The functions described here are wrapper functions that ultimately call
|
||||
the PCRE2 native API. Their prototypes are defined in the pcre2posix.h
|
||||
header file, and they all have unique names starting with pcre2_. How-
|
||||
ever, the pcre2posix.h header also contains macro definitions that con-
|
||||
vert the standard POSIX names such regcomp() into pcre2_regcomp() etc.
|
||||
This means that a program can use the usual POSIX names without running
|
||||
the risk of accidentally linking with POSIX functions from a different
|
||||
library.
|
||||
|
||||
When another POSIX regex library is also installed, there is the possi-
|
||||
bility of linking an application with the wrong library. To help avoid
|
||||
this issue, the PCRE2 POSIX library provides alternative names for the
|
||||
functions, all starting with "pcre2_". If an application uses these
|
||||
names, possible ambiguity is avoided. In the following description,
|
||||
however, the standard POSIX function names are used.
|
||||
On Unix-like systems the PCRE2 POSIX library is called libpcre2-posix,
|
||||
so can be accessed by adding -lpcre2-posix to the command for linking
|
||||
an application. Because the POSIX functions call the native ones, it is
|
||||
also necessary to add -lpcre2-8.
|
||||
|
||||
Those POSIX option bits that can reasonably be mapped to PCRE2 native
|
||||
options have been implemented. In addition, the option REG_EXTENDED is
|
||||
defined with the value zero. This has no effect, but since programs
|
||||
that are written to the POSIX interface often use it, this makes it
|
||||
easier to slot in PCRE2 as a replacement library. Other POSIX options
|
||||
Although they are not defined as protypes in pcre2posix.h, the library
|
||||
does contain functions with the POSIX names regcomp() etc. These simply
|
||||
pass their arguments to the PCRE2 functions. These functions are pro-
|
||||
vided for backwards compatibility with earlier versions of PCRE2, so
|
||||
that existing programs do not have to be recompiled.
|
||||
|
||||
Calling the header file pcre2posix.h avoids any conflict with other
|
||||
POSIX libraries. It can, of course, be renamed or aliased as regex.h,
|
||||
which is the "correct" name, if there is no clash. It provides two
|
||||
structure types, regex_t for compiled internal forms, and regmatch_t
|
||||
for returning captured substrings. It also defines some constants whose
|
||||
names start with "REG_"; these are used for setting options and identi-
|
||||
fying error codes.
|
||||
|
||||
|
||||
USING THE POSIX FUNCTIONS
|
||||
|
||||
Those POSIX option bits that can reasonably be mapped to PCRE2 native
|
||||
options have been implemented. In addition, the option REG_EXTENDED is
|
||||
defined with the value zero. This has no effect, but since programs
|
||||
that are written to the POSIX interface often use it, this makes it
|
||||
easier to slot in PCRE2 as a replacement library. Other POSIX options
|
||||
are not even defined.
|
||||
|
||||
There are also some options that are not defined by POSIX. These have
|
||||
been added at the request of users who want to make use of certain
|
||||
PCRE2-specific features via the POSIX calling interface or to add BSD
|
||||
There are also some options that are not defined by POSIX. These have
|
||||
been added at the request of users who want to make use of certain
|
||||
PCRE2-specific features via the POSIX calling interface or to add BSD
|
||||
or GNU functionality.
|
||||
|
||||
When PCRE2 is called via these functions, it is only the API that is
|
||||
POSIX-like in style. The syntax and semantics of the regular expres-
|
||||
sions themselves are still those of Perl, subject to the setting of
|
||||
various PCRE2 options, as described below. "POSIX-like in style" means
|
||||
that the API approximates to the POSIX definition; it is not fully
|
||||
POSIX-compatible, and in multi-unit encoding domains it is probably
|
||||
When PCRE2 is called via these functions, it is only the API that is
|
||||
POSIX-like in style. The syntax and semantics of the regular expres-
|
||||
sions themselves are still those of Perl, subject to the setting of
|
||||
various PCRE2 options, as described below. "POSIX-like in style" means
|
||||
that the API approximates to the POSIX definition; it is not fully
|
||||
POSIX-compatible, and in multi-unit encoding domains it is probably
|
||||
even less compatible.
|
||||
|
||||
The header for these functions is supplied as pcre2posix.h to avoid any
|
||||
potential clash with other POSIX libraries. It can, of course, be
|
||||
renamed or aliased as regex.h, which is the "correct" name. It provides
|
||||
two structure types, regex_t for compiled internal forms, and reg-
|
||||
match_t for returning captured substrings. It also defines some con-
|
||||
stants whose names start with "REG_"; these are used for setting
|
||||
options and identifying error codes.
|
||||
The descriptions below use the actual names of the functions, but, as
|
||||
described above, the standard POSIX names (without the pcre2_ prefix)
|
||||
may also be used.
|
||||
|
||||
|
||||
COMPILING A PATTERN
|
||||
|
||||
The function regcomp() is called to compile a pattern into an internal
|
||||
form. By default, the pattern is a C string terminated by a binary zero
|
||||
(but see REG_PEND below). The preg argument is a pointer to a regex_t
|
||||
structure that is used as a base for storing information about the com-
|
||||
piled regular expression. (It is also used for input when REG_PEND is
|
||||
set.)
|
||||
The function pcre2_regcomp() is called to compile a pattern into an
|
||||
internal form. By default, the pattern is a C string terminated by a
|
||||
binary zero (but see REG_PEND below). The preg argument is a pointer to
|
||||
a regex_t structure that is used as a base for storing information
|
||||
about the compiled regular expression. (It is also used for input when
|
||||
REG_PEND is set.)
|
||||
|
||||
The argument cflags is either zero, or contains one or more of the bits
|
||||
defined by the following macros:
|
||||
|
||||
REG_DOTALL
|
||||
|
||||
The PCRE2_DOTALL option is set when the regular expression is passed
|
||||
for compilation to the native function. Note that REG_DOTALL is not
|
||||
The PCRE2_DOTALL option is set when the regular expression is passed
|
||||
for compilation to the native function. Note that REG_DOTALL is not
|
||||
part of the POSIX standard.
|
||||
|
||||
REG_ICASE
|
||||
|
||||
The PCRE2_CASELESS option is set when the regular expression is passed
|
||||
The PCRE2_CASELESS option is set when the regular expression is passed
|
||||
for compilation to the native function.
|
||||
|
||||
REG_NEWLINE
|
||||
|
||||
The PCRE2_MULTILINE option is set when the regular expression is passed
|
||||
for compilation to the native function. Note that this does not mimic
|
||||
the defined POSIX behaviour for REG_NEWLINE (see the following sec-
|
||||
for compilation to the native function. Note that this does not mimic
|
||||
the defined POSIX behaviour for REG_NEWLINE (see the following sec-
|
||||
tion).
|
||||
|
||||
REG_NOSPEC
|
||||
|
||||
The PCRE2_LITERAL option is set when the regular expression is passed
|
||||
for compilation to the native function. This disables all meta charac-
|
||||
ters in the pattern, causing it to be treated as a literal string. The
|
||||
only other options that are allowed with REG_NOSPEC are REG_ICASE,
|
||||
REG_NOSUB, REG_PEND, and REG_UTF. Note that REG_NOSPEC is not part of
|
||||
The PCRE2_LITERAL option is set when the regular expression is passed
|
||||
for compilation to the native function. This disables all meta charac-
|
||||
ters in the pattern, causing it to be treated as a literal string. The
|
||||
only other options that are allowed with REG_NOSPEC are REG_ICASE,
|
||||
REG_NOSUB, REG_PEND, and REG_UTF. Note that REG_NOSPEC is not part of
|
||||
the POSIX standard.
|
||||
|
||||
REG_NOSUB
|
||||
|
||||
When a pattern that is compiled with this flag is passed to regexec()
|
||||
for matching, the nmatch and pmatch arguments are ignored, and no cap-
|
||||
tured strings are returned. Versions of the PCRE library prior to 10.22
|
||||
used to set the PCRE2_NO_AUTO_CAPTURE compile option, but this no
|
||||
longer happens because it disables the use of backreferences.
|
||||
When a pattern that is compiled with this flag is passed to
|
||||
pcre2_regexec() for matching, the nmatch and pmatch arguments are
|
||||
ignored, and no captured strings are returned. Versions of the PCRE
|
||||
library prior to 10.22 used to set the PCRE2_NO_AUTO_CAPTURE compile
|
||||
option, but this no longer happens because it disables the use of back-
|
||||
references.
|
||||
|
||||
REG_PEND
|
||||
|
||||
If this option is set, the reg_endp field in the preg structure (which
|
||||
has the type const char *) must be set to point to the character beyond
|
||||
the end of the pattern before calling regcomp(). The pattern itself may
|
||||
now contain binary zeros, which are treated as data characters. Without
|
||||
REG_PEND, a binary zero terminates the pattern and the re_endp field is
|
||||
ignored. This is a GNU extension to the POSIX standard and should be
|
||||
used with caution in software intended to be portable to other systems.
|
||||
the end of the pattern before calling pcre2_regcomp(). The pattern
|
||||
itself may now contain binary zeros, which are treated as data charac-
|
||||
ters. Without REG_PEND, a binary zero terminates the pattern and the
|
||||
re_endp field is ignored. This is a GNU extension to the POSIX standard
|
||||
and should be used with caution in software intended to be portable to
|
||||
other systems.
|
||||
|
||||
REG_UCP
|
||||
|
||||
The PCRE2_UCP option is set when the regular expression is passed for
|
||||
compilation to the native function. This causes PCRE2 to use Unicode
|
||||
properties when matchine \d, \w, etc., instead of just recognizing
|
||||
The PCRE2_UCP option is set when the regular expression is passed for
|
||||
compilation to the native function. This causes PCRE2 to use Unicode
|
||||
properties when matchine \d, \w, etc., instead of just recognizing
|
||||
ASCII values. Note that REG_UCP is not part of the POSIX standard.
|
||||
|
||||
REG_UNGREEDY
|
||||
|
||||
The PCRE2_UNGREEDY option is set when the regular expression is passed
|
||||
for compilation to the native function. Note that REG_UNGREEDY is not
|
||||
The PCRE2_UNGREEDY option is set when the regular expression is passed
|
||||
for compilation to the native function. Note that REG_UNGREEDY is not
|
||||
part of the POSIX standard.
|
||||
|
||||
REG_UTF
|
||||
|
||||
The PCRE2_UTF option is set when the regular expression is passed for
|
||||
compilation to the native function. This causes the pattern itself and
|
||||
all data strings used for matching it to be treated as UTF-8 strings.
|
||||
The PCRE2_UTF option is set when the regular expression is passed for
|
||||
compilation to the native function. This causes the pattern itself and
|
||||
all data strings used for matching it to be treated as UTF-8 strings.
|
||||
Note that REG_UTF is not part of the POSIX standard.
|
||||
|
||||
In the absence of these flags, no options are passed to the native
|
||||
function. This means the the regex is compiled with PCRE2 default
|
||||
semantics. In particular, the way it handles newline characters in the
|
||||
subject string is the Perl way, not the POSIX way. Note that setting
|
||||
In the absence of these flags, no options are passed to the native
|
||||
function. This means the the regex is compiled with PCRE2 default
|
||||
semantics. In particular, the way it handles newline characters in the
|
||||
subject string is the Perl way, not the POSIX way. Note that setting
|
||||
PCRE2_MULTILINE has only some of the effects specified for REG_NEWLINE.
|
||||
It does not affect the way newlines are matched by the dot metacharac-
|
||||
It does not affect the way newlines are matched by the dot metacharac-
|
||||
ter (they are not) or by a negative class such as [^a] (they are).
|
||||
|
||||
The yield of regcomp() is zero on success, and non-zero otherwise. The
|
||||
preg structure is filled in on success, and one other member of the
|
||||
structure (as well as re_endp) is public: re_nsub contains the number
|
||||
of capturing subpatterns in the regular expression. Various error codes
|
||||
are defined in the header file.
|
||||
The yield of pcre2_regcomp() is zero on success, and non-zero other-
|
||||
wise. The preg structure is filled in on success, and one other member
|
||||
of the structure (as well as re_endp) is public: re_nsub contains the
|
||||
number of capturing subpatterns in the regular expression. Various
|
||||
error codes are defined in the header file.
|
||||
|
||||
NOTE: If the yield of regcomp() is non-zero, you must not attempt to
|
||||
use the contents of the preg structure. If, for example, you pass it to
|
||||
regexec(), the result is undefined and your program is likely to crash.
|
||||
NOTE: If the yield of pcre2_regcomp() is non-zero, you must not attempt
|
||||
to use the contents of the preg structure. If, for example, you pass it
|
||||
to pcre2_regexec(), the result is undefined and your program is likely
|
||||
to crash.
|
||||
|
||||
|
||||
MATCHING NEWLINE CHARACTERS
|
||||
|
@ -9792,17 +9796,17 @@ MATCHING NEWLINE CHARACTERS
|
|||
Default POSIX newline handling can be obtained by setting PCRE2_DOTALL
|
||||
and PCRE2_DOLLAR_ENDONLY when calling pcre2_compile() directly, but
|
||||
there is no way to make PCRE2 behave exactly as for the REG_NEWLINE
|
||||
action. When using the POSIX API, passing REG_NEWLINE to PCRE2's reg-
|
||||
comp() function causes PCRE2_MULTILINE to be passed to pcre2_compile(),
|
||||
and REG_DOTALL passes PCRE2_DOTALL. There is no way to pass PCRE2_DOL-
|
||||
LAR_ENDONLY.
|
||||
action. When using the POSIX API, passing REG_NEWLINE to PCRE2's
|
||||
pcre2_regcomp() function causes PCRE2_MULTILINE to be passed to
|
||||
pcre2_compile(), and REG_DOTALL passes PCRE2_DOTALL. There is no way to
|
||||
pass PCRE2_DOLLAR_ENDONLY.
|
||||
|
||||
|
||||
MATCHING A PATTERN
|
||||
|
||||
The function regexec() is called to match a compiled pattern preg
|
||||
The function pcre2_regexec() is called to match a compiled pattern preg
|
||||
against a given string, which is by default terminated by a zero byte
|
||||
(but see REG_STARTEND below), subject to the options in eflags. These
|
||||
(but see REG_STARTEND below), subject to the options in eflags. These
|
||||
can be:
|
||||
|
||||
REG_NOTBOL
|
||||
|
@ -9846,45 +9850,46 @@ MATCHING A PATTERN
|
|||
|
||||
If the pattern was compiled with the REG_NOSUB flag, no data about any
|
||||
matched strings is returned. The nmatch and pmatch arguments of
|
||||
regexec() are ignored (except possibly as input for REG_STARTEND).
|
||||
pcre2_regexec() are ignored (except possibly as input for REG_STAR-
|
||||
TEND).
|
||||
|
||||
The value of nmatch may be zero, and the value pmatch may be NULL
|
||||
(unless REG_STARTEND is set); in both these cases no data about any
|
||||
The value of nmatch may be zero, and the value pmatch may be NULL
|
||||
(unless REG_STARTEND is set); in both these cases no data about any
|
||||
matched strings is returned.
|
||||
|
||||
Otherwise, the portion of the string that was matched, and also any
|
||||
Otherwise, the portion of the string that was matched, and also any
|
||||
captured substrings, are returned via the pmatch argument, which points
|
||||
to an array of nmatch structures of type regmatch_t, containing the
|
||||
members rm_so and rm_eo. These contain the byte offset to the first
|
||||
to an array of nmatch structures of type regmatch_t, containing the
|
||||
members rm_so and rm_eo. These contain the byte offset to the first
|
||||
character of each substring and the offset to the first character after
|
||||
the end of each substring, respectively. The 0th element of the vector
|
||||
relates to the entire portion of string that was matched; subsequent
|
||||
the end of each substring, respectively. The 0th element of the vector
|
||||
relates to the entire portion of string that was matched; subsequent
|
||||
elements relate to the capturing subpatterns of the regular expression.
|
||||
Unused entries in the array have both structure members set to -1.
|
||||
|
||||
A successful match yields a zero return; various error codes are
|
||||
defined in the header file, of which REG_NOMATCH is the "expected"
|
||||
A successful match yields a zero return; various error codes are
|
||||
defined in the header file, of which REG_NOMATCH is the "expected"
|
||||
failure code.
|
||||
|
||||
|
||||
ERROR MESSAGES
|
||||
|
||||
The regerror() function maps a non-zero errorcode from either regcomp()
|
||||
or regexec() to a printable message. If preg is not NULL, the error
|
||||
should have arisen from the use of that structure. A message terminated
|
||||
by a binary zero is placed in errbuf. If the buffer is too short, only
|
||||
the first errbuf_size - 1 characters of the error message are used. The
|
||||
yield of the function is the size of buffer needed to hold the whole
|
||||
message, including the terminating zero. This value is greater than
|
||||
errbuf_size if the message was truncated.
|
||||
The pcre2_regerror() function maps a non-zero errorcode from either
|
||||
pcre2_regcomp() or pcre2_regexec() to a printable message. If preg is
|
||||
not NULL, the error should have arisen from the use of that structure.
|
||||
A message terminated by a binary zero is placed in errbuf. If the buf-
|
||||
fer is too short, only the first errbuf_size - 1 characters of the
|
||||
error message are used. The yield of the function is the size of buffer
|
||||
needed to hold the whole message, including the terminating zero. This
|
||||
value is greater than errbuf_size if the message was truncated.
|
||||
|
||||
|
||||
MEMORY USAGE
|
||||
|
||||
Compiling a regular expression causes memory to be allocated and asso-
|
||||
ciated with the preg structure. The function regfree() frees all such
|
||||
memory, after which preg may no longer be used as a compiled expres-
|
||||
sion.
|
||||
Compiling a regular expression causes memory to be allocated and asso-
|
||||
ciated with the preg structure. The function pcre2_regfree() frees all
|
||||
such memory, after which preg may no longer be used as a compiled
|
||||
expression.
|
||||
|
||||
|
||||
AUTHOR
|
||||
|
@ -9896,8 +9901,8 @@ AUTHOR
|
|||
|
||||
REVISION
|
||||
|
||||
Last updated: 19 September 2018
|
||||
Copyright (c) 1997-2018 University of Cambridge.
|
||||
Last updated: 30 January 2019
|
||||
Copyright (c) 1997-2019 University of Cambridge.
|
||||
------------------------------------------------------------------------------
|
||||
|
||||
|
||||
|
|
133
doc/pcre2posix.3
133
doc/pcre2posix.3
|
@ -1,4 +1,4 @@
|
|||
.TH PCRE2POSIX 3 "19 September 2018" "PCRE2 10.33"
|
||||
.TH PCRE2POSIX 3 "30 January 2019" "PCRE2 10.33"
|
||||
.SH NAME
|
||||
PCRE2 - Perl-compatible regular expressions (revised API)
|
||||
.SH "SYNOPSIS"
|
||||
|
@ -7,26 +7,15 @@ PCRE2 - Perl-compatible regular expressions (revised API)
|
|||
.B #include <pcre2posix.h>
|
||||
.PP
|
||||
.nf
|
||||
.B int regcomp(regex_t *\fIpreg\fP, const char *\fIpattern\fP,
|
||||
.B " int \fIcflags\fP);"
|
||||
.sp
|
||||
.B int pcre2_regcomp(regex_t *\fIpreg\fP, const char *\fIpattern\fP,
|
||||
.B " int \fIcflags\fP);"
|
||||
.sp
|
||||
.B int regexec(const regex_t *\fIpreg\fP, const char *\fIstring\fP,
|
||||
.B " size_t \fInmatch\fP, regmatch_t \fIpmatch\fP[], int \fIeflags\fP);"
|
||||
.sp
|
||||
.B int pcre2_regexec(const regex_t *\fIpreg\fP, const char *\fIstring\fP,
|
||||
.B " size_t \fInmatch\fP, regmatch_t \fIpmatch\fP[], int \fIeflags\fP);"
|
||||
.sp
|
||||
.B "size_t regerror(int \fIerrcode\fP, const regex_t *\fIpreg\fP,"
|
||||
.B " char *\fIerrbuf\fP, size_t \fIerrbuf_size\fP);"
|
||||
.sp
|
||||
.B "size_t pcre2_regerror(int \fIerrcode\fP, const regex_t *\fIpreg\fP,"
|
||||
.B " char *\fIerrbuf\fP, size_t \fIerrbuf_size\fP);"
|
||||
.sp
|
||||
.B void regfree(regex_t *\fIpreg\fP);
|
||||
.sp
|
||||
.B void pcre2_regfree(regex_t *\fIpreg\fP);
|
||||
.fi
|
||||
.
|
||||
|
@ -34,28 +23,44 @@ PCRE2 - Perl-compatible regular expressions (revised API)
|
|||
.rs
|
||||
.sp
|
||||
This set of functions provides a POSIX-style API for the PCRE2 regular
|
||||
expression 8-bit library. See the
|
||||
expression 8-bit library. There are no POSIX-style wrappers for PCRE2's 16-bit
|
||||
and 32-bit libraries. See the
|
||||
.\" HREF
|
||||
\fBpcre2api\fP
|
||||
.\"
|
||||
documentation for a description of PCRE2's native API, which contains much
|
||||
additional functionality. There are no POSIX-style wrappers for PCRE2's 16-bit
|
||||
and 32-bit libraries.
|
||||
additional functionality.
|
||||
.P
|
||||
The functions described here are just wrapper functions that ultimately call
|
||||
the PCRE2 native API. Their prototypes are defined in the \fBpcre2posix.h\fP
|
||||
header file, and on Unix systems the library itself is called
|
||||
\fBlibpcre2-posix.a\fP, so can be accessed by adding \fB-lpcre2-posix\fP to the
|
||||
command for linking an application that uses them. Because the POSIX functions
|
||||
call the native ones, it is also necessary to add \fB-lpcre2-8\fP.
|
||||
The functions described here are wrapper functions that ultimately call the
|
||||
PCRE2 native API. Their prototypes are defined in the \fBpcre2posix.h\fP header
|
||||
file, and they all have unique names starting with \fBpcre2_\fP. However, the
|
||||
\fBpcre2posix.h\fP header also contains macro definitions that convert the
|
||||
standard POSIX names such \fBregcomp()\fP into \fBpcre2_regcomp()\fP etc. This
|
||||
means that a program can use the usual POSIX names without running the risk of
|
||||
accidentally linking with POSIX functions from a different library.
|
||||
.P
|
||||
When another POSIX regex library is also installed, there is the possibility of
|
||||
linking an application with the wrong library. To help avoid this issue, the
|
||||
PCRE2 POSIX library provides alternative names for the functions, all starting
|
||||
with "pcre2_". If an application uses these names, possible ambiguity is
|
||||
avoided. In the following description, however, the standard POSIX function
|
||||
names are used.
|
||||
On Unix-like systems the PCRE2 POSIX library is called \fBlibpcre2-posix\fP, so
|
||||
can be accessed by adding \fB-lpcre2-posix\fP to the command for linking an
|
||||
application. Because the POSIX functions call the native ones, it is also
|
||||
necessary to add \fB-lpcre2-8\fP.
|
||||
.P
|
||||
Although they are not defined as protypes in \fBpcre2posix.h\fP, the library
|
||||
does contain functions with the POSIX names \fBregcomp()\fP etc. These simply
|
||||
pass their arguments to the PCRE2 functions. These functions are provided for
|
||||
backwards compatibility with earlier versions of PCRE2, so that existing
|
||||
programs do not have to be recompiled.
|
||||
.P
|
||||
Calling the header file \fBpcre2posix.h\fP avoids any conflict with other POSIX
|
||||
libraries. It can, of course, be renamed or aliased as \fBregex.h\fP, which is
|
||||
the "correct" name, if there is no clash. It provides two structure types,
|
||||
\fIregex_t\fP for compiled internal forms, and \fIregmatch_t\fP for returning
|
||||
captured substrings. It also defines some constants whose names start with
|
||||
"REG_"; these are used for setting options and identifying error codes.
|
||||
.
|
||||
.
|
||||
.SH "USING THE POSIX FUNCTIONS"
|
||||
.rs
|
||||
.sp
|
||||
Those POSIX option bits that can reasonably be mapped to PCRE2 native options
|
||||
have been implemented. In addition, the option REG_EXTENDED is defined with the
|
||||
value zero. This has no effect, but since programs that are written to the
|
||||
|
@ -73,19 +78,15 @@ described below. "POSIX-like in style" means that the API approximates to the
|
|||
POSIX definition; it is not fully POSIX-compatible, and in multi-unit encoding
|
||||
domains it is probably even less compatible.
|
||||
.P
|
||||
The header for these functions is supplied as \fBpcre2posix.h\fP to avoid any
|
||||
potential clash with other POSIX libraries. It can, of course, be renamed or
|
||||
aliased as \fBregex.h\fP, which is the "correct" name. It provides two
|
||||
structure types, \fIregex_t\fP for compiled internal forms, and
|
||||
\fIregmatch_t\fP for returning captured substrings. It also defines some
|
||||
constants whose names start with "REG_"; these are used for setting options and
|
||||
identifying error codes.
|
||||
The descriptions below use the actual names of the functions, but, as described
|
||||
above, the standard POSIX names (without the \fBpcre2_\fP prefix) may also be
|
||||
used.
|
||||
.
|
||||
.
|
||||
.SH "COMPILING A PATTERN"
|
||||
.rs
|
||||
.sp
|
||||
The function \fBregcomp()\fP is called to compile a pattern into an
|
||||
The function \fBpcre2_regcomp()\fP is called to compile a pattern into an
|
||||
internal form. By default, the pattern is a C string terminated by a binary
|
||||
zero (but see REG_PEND below). The \fIpreg\fP argument is a pointer to a
|
||||
\fBregex_t\fP structure that is used as a base for storing information about
|
||||
|
@ -122,18 +123,18 @@ REG_UTF. Note that REG_NOSPEC is not part of the POSIX standard.
|
|||
.sp
|
||||
REG_NOSUB
|
||||
.sp
|
||||
When a pattern that is compiled with this flag is passed to \fBregexec()\fP for
|
||||
matching, the \fInmatch\fP and \fIpmatch\fP arguments are ignored, and no
|
||||
captured strings are returned. Versions of the PCRE library prior to 10.22 used
|
||||
to set the PCRE2_NO_AUTO_CAPTURE compile option, but this no longer happens
|
||||
because it disables the use of backreferences.
|
||||
When a pattern that is compiled with this flag is passed to
|
||||
\fBpcre2_regexec()\fP for matching, the \fInmatch\fP and \fIpmatch\fP arguments
|
||||
are ignored, and no captured strings are returned. Versions of the PCRE library
|
||||
prior to 10.22 used to set the PCRE2_NO_AUTO_CAPTURE compile option, but this
|
||||
no longer happens because it disables the use of backreferences.
|
||||
.sp
|
||||
REG_PEND
|
||||
.sp
|
||||
If this option is set, the \fBreg_endp\fP field in the \fIpreg\fP structure
|
||||
(which has the type const char *) must be set to point to the character beyond
|
||||
the end of the pattern before calling \fBregcomp()\fP. The pattern itself may
|
||||
now contain binary zeros, which are treated as data characters. Without
|
||||
the end of the pattern before calling \fBpcre2_regcomp()\fP. The pattern itself
|
||||
may now contain binary zeros, which are treated as data characters. Without
|
||||
REG_PEND, a binary zero terminates the pattern and the \fBre_endp\fP field is
|
||||
ignored. This is a GNU extension to the POSIX standard and should be used with
|
||||
caution in software intended to be portable to other systems.
|
||||
|
@ -166,15 +167,16 @@ Perl way, not the POSIX way. Note that setting PCRE2_MULTILINE has only
|
|||
newlines are matched by the dot metacharacter (they are not) or by a negative
|
||||
class such as [^a] (they are).
|
||||
.P
|
||||
The yield of \fBregcomp()\fP is zero on success, and non-zero otherwise. The
|
||||
\fIpreg\fP structure is filled in on success, and one other member of the
|
||||
The yield of \fBpcre2_regcomp()\fP is zero on success, and non-zero otherwise.
|
||||
The \fIpreg\fP structure is filled in on success, and one other member of the
|
||||
structure (as well as \fIre_endp\fP) is public: \fIre_nsub\fP contains the
|
||||
number of capturing subpatterns in the regular expression. Various error codes
|
||||
are defined in the header file.
|
||||
.P
|
||||
NOTE: If the yield of \fBregcomp()\fP is non-zero, you must not attempt to
|
||||
use the contents of the \fIpreg\fP structure. If, for example, you pass it to
|
||||
\fBregexec()\fP, the result is undefined and your program is likely to crash.
|
||||
NOTE: If the yield of \fBpcre2_regcomp()\fP is non-zero, you must not attempt
|
||||
to use the contents of the \fIpreg\fP structure. If, for example, you pass it
|
||||
to \fBpcre2_regexec()\fP, the result is undefined and your program is likely to
|
||||
crash.
|
||||
.
|
||||
.
|
||||
.SH "MATCHING NEWLINE CHARACTERS"
|
||||
|
@ -211,7 +213,7 @@ is no way to stop newline from matching [^a].
|
|||
Default POSIX newline handling can be obtained by setting PCRE2_DOTALL and
|
||||
PCRE2_DOLLAR_ENDONLY when calling \fBpcre2_compile()\fP directly, but there is
|
||||
no way to make PCRE2 behave exactly as for the REG_NEWLINE action. When using
|
||||
the POSIX API, passing REG_NEWLINE to PCRE2's \fBregcomp()\fP function
|
||||
the POSIX API, passing REG_NEWLINE to PCRE2's \fBpcre2_regcomp()\fP function
|
||||
causes PCRE2_MULTILINE to be passed to \fBpcre2_compile()\fP, and REG_DOTALL
|
||||
passes PCRE2_DOTALL. There is no way to pass PCRE2_DOLLAR_ENDONLY.
|
||||
.
|
||||
|
@ -219,10 +221,10 @@ passes PCRE2_DOTALL. There is no way to pass PCRE2_DOLLAR_ENDONLY.
|
|||
.SH "MATCHING A PATTERN"
|
||||
.rs
|
||||
.sp
|
||||
The function \fBregexec()\fP is called to match a compiled pattern \fIpreg\fP
|
||||
against a given \fIstring\fP, which is by default terminated by a zero byte
|
||||
(but see REG_STARTEND below), subject to the options in \fIeflags\fP. These can
|
||||
be:
|
||||
The function \fBpcre2_regexec()\fP is called to match a compiled pattern
|
||||
\fIpreg\fP against a given \fIstring\fP, which is by default terminated by a
|
||||
zero byte (but see REG_STARTEND below), subject to the options in \fIeflags\fP.
|
||||
These can be:
|
||||
.sp
|
||||
REG_NOTBOL
|
||||
.sp
|
||||
|
@ -263,7 +265,7 @@ are mutually exclusive; the error REG_INVARG is returned.
|
|||
.P
|
||||
If the pattern was compiled with the REG_NOSUB flag, no data about any matched
|
||||
strings is returned. The \fInmatch\fP and \fIpmatch\fP arguments of
|
||||
\fBregexec()\fP are ignored (except possibly as input for REG_STARTEND).
|
||||
\fBpcre2_regexec()\fP are ignored (except possibly as input for REG_STARTEND).
|
||||
.P
|
||||
The value of \fInmatch\fP may be zero, and the value \fIpmatch\fP may be NULL
|
||||
(unless REG_STARTEND is set); in both these cases no data about any matched
|
||||
|
@ -286,22 +288,23 @@ header file, of which REG_NOMATCH is the "expected" failure code.
|
|||
.SH "ERROR MESSAGES"
|
||||
.rs
|
||||
.sp
|
||||
The \fBregerror()\fP function maps a non-zero errorcode from either
|
||||
\fBregcomp()\fP or \fBregexec()\fP to a printable message. If \fIpreg\fP is not
|
||||
NULL, the error should have arisen from the use of that structure. A message
|
||||
terminated by a binary zero is placed in \fIerrbuf\fP. If the buffer is too
|
||||
short, only the first \fIerrbuf_size\fP - 1 characters of the error message are
|
||||
used. The yield of the function is the size of buffer needed to hold the whole
|
||||
message, including the terminating zero. This value is greater than
|
||||
\fIerrbuf_size\fP if the message was truncated.
|
||||
The \fBpcre2_regerror()\fP function maps a non-zero errorcode from either
|
||||
\fBpcre2_regcomp()\fP or \fBpcre2_regexec()\fP to a printable message. If
|
||||
\fIpreg\fP is not NULL, the error should have arisen from the use of that
|
||||
structure. A message terminated by a binary zero is placed in \fIerrbuf\fP. If
|
||||
the buffer is too short, only the first \fIerrbuf_size\fP - 1 characters of the
|
||||
error message are used. The yield of the function is the size of buffer needed
|
||||
to hold the whole message, including the terminating zero. This value is
|
||||
greater than \fIerrbuf_size\fP if the message was truncated.
|
||||
.
|
||||
.
|
||||
.SH MEMORY USAGE
|
||||
.rs
|
||||
.sp
|
||||
Compiling a regular expression causes memory to be allocated and associated
|
||||
with the \fIpreg\fP structure. The function \fBregfree()\fP frees all such
|
||||
memory, after which \fIpreg\fP may no longer be used as a compiled expression.
|
||||
with the \fIpreg\fP structure. The function \fBpcre2_regfree()\fP frees all
|
||||
such memory, after which \fIpreg\fP may no longer be used as a compiled
|
||||
expression.
|
||||
.
|
||||
.
|
||||
.SH AUTHOR
|
||||
|
@ -318,6 +321,6 @@ Cambridge, England.
|
|||
.rs
|
||||
.sp
|
||||
.nf
|
||||
Last updated: 19 September 2018
|
||||
Copyright (c) 1997-2018 University of Cambridge.
|
||||
Last updated: 30 January 2019
|
||||
Copyright (c) 1997-2019 University of Cambridge.
|
||||
.fi
|
||||
|
|
|
@ -7,7 +7,7 @@ and semantics are as close as possible to those of the Perl 5 language.
|
|||
|
||||
Written by Philip Hazel
|
||||
Original API code Copyright (c) 1997-2012 University of Cambridge
|
||||
New API code Copyright (c) 2016-2018 University of Cambridge
|
||||
New API code Copyright (c) 2016-2019 University of Cambridge
|
||||
|
||||
-----------------------------------------------------------------------------
|
||||
Redistribution and use in source and binary forms, with or without
|
||||
|
@ -41,9 +41,11 @@ POSSIBILITY OF SUCH DAMAGE.
|
|||
|
||||
/* This module is a wrapper that provides a POSIX API to the underlying PCRE2
|
||||
functions. The operative functions are called pcre2_regcomp(), etc., with
|
||||
wrappers that use the plain POSIX names. This makes it easier for an
|
||||
application to be sure it gets the PCRE2 versions in the presence of other
|
||||
POSIX regex libraries. */
|
||||
wrappers that use the plain POSIX names. In addition, pcre2posix.h defines the
|
||||
POSIX names as macros for the pcre2_xxx functions, so any program that includes
|
||||
it and uses the POSIX names will call the base functions directly. This makes
|
||||
it easier for an application to be sure it gets the PCRE2 versions in the
|
||||
presence of other POSIX regex libraries. */
|
||||
|
||||
|
||||
#ifdef HAVE_CONFIG_H
|
||||
|
@ -177,24 +179,39 @@ static const char *const pstring[] = {
|
|||
* Wrappers with traditional POSIX names *
|
||||
*************************************************/
|
||||
|
||||
/* Keep defining them to preseve the ABI for applications linked to the pcre2
|
||||
POSIX library before these names were changed into macros in pcre2posix.h.
|
||||
This also ensures that the POSIX names are callable from languages that do not
|
||||
include pcre2posix.h. It is vital to #undef the macro definitions from
|
||||
pcre2posix.h! */
|
||||
|
||||
#undef regerror
|
||||
PCRE2POSIX_EXP_DECL size_t regerror(int, const regex_t *, char *, size_t);
|
||||
PCRE2POSIX_EXP_DEFN size_t PCRE2_CALL_CONVENTION
|
||||
regerror(int errcode, const regex_t *preg, char *errbuf, size_t errbuf_size)
|
||||
{
|
||||
return pcre2_regerror(errcode, preg, errbuf, errbuf_size);
|
||||
}
|
||||
|
||||
#undef regfree
|
||||
PCRE2POSIX_EXP_DECL void regfree(regex_t *);
|
||||
PCRE2POSIX_EXP_DEFN void PCRE2_CALL_CONVENTION
|
||||
regfree(regex_t *preg)
|
||||
{
|
||||
pcre2_regfree(preg);
|
||||
}
|
||||
|
||||
#undef regcomp
|
||||
PCRE2POSIX_EXP_DECL int regcomp(regex_t *, const char *, int);
|
||||
PCRE2POSIX_EXP_DEFN int PCRE2_CALL_CONVENTION
|
||||
regcomp(regex_t *preg, const char *pattern, int cflags)
|
||||
{
|
||||
return pcre2_regcomp(preg, pattern, cflags);
|
||||
}
|
||||
|
||||
#undef regexec
|
||||
PCRE2POSIX_EXP_DECL int regexec(const regex_t *, const char *, size_t,
|
||||
regmatch_t *, int);
|
||||
PCRE2POSIX_EXP_DEFN int PCRE2_CALL_CONVENTION
|
||||
regexec(const regex_t *preg, const char *string, size_t nmatch,
|
||||
regmatch_t pmatch[], int eflags)
|
||||
|
@ -209,7 +226,7 @@ return pcre2_regexec(preg, string, nmatch, pmatch, eflags);
|
|||
*************************************************/
|
||||
|
||||
PCRE2POSIX_EXP_DEFN size_t PCRE2_CALL_CONVENTION
|
||||
pcre2_regerror(int errcode, const regex_t *preg, char *errbuf,
|
||||
pcre2_regerror(int errcode, const regex_t *preg, char *errbuf,
|
||||
size_t errbuf_size)
|
||||
{
|
||||
int used;
|
||||
|
|
|
@ -9,7 +9,7 @@ POSIX wrapper interface.
|
|||
|
||||
Written by Philip Hazel
|
||||
Original API code Copyright (c) 1997-2012 University of Cambridge
|
||||
New API code Copyright (c) 2016-2018 University of Cambridge
|
||||
New API code Copyright (c) 2016-2019 University of Cambridge
|
||||
|
||||
-----------------------------------------------------------------------------
|
||||
Redistribution and use in source and binary forms, with or without
|
||||
|
@ -139,22 +139,29 @@ file. */
|
|||
#endif
|
||||
|
||||
/* The functions. The actual code is in functions with pcre2_xxx names for
|
||||
uniqueness. Wrappers with the POSIX names are provided for those who can ensure
|
||||
they get them from the PCRE2 library and not by accident from elsewhere. */
|
||||
uniqueness. POSIX names are provided as macros for API compatibility with POSIX
|
||||
regex functions. It's done this way to ensure to they are always linked from
|
||||
the PCRE2 library and not by accident from elsewhere (regex_t differs in size
|
||||
elsewhere). */
|
||||
|
||||
PCRE2POSIX_EXP_DECL int pcre2_regcomp(regex_t *, const char *, int);
|
||||
PCRE2POSIX_EXP_DECL int regcomp(regex_t *, const char *, int);
|
||||
|
||||
PCRE2POSIX_EXP_DECL int pcre2_regexec(const regex_t *, const char *, size_t,
|
||||
regmatch_t *, int);
|
||||
PCRE2POSIX_EXP_DECL int regexec(const regex_t *, const char *, size_t,
|
||||
regmatch_t *, int);
|
||||
|
||||
PCRE2POSIX_EXP_DECL size_t pcre2_regerror(int, const regex_t *, char *, size_t);
|
||||
PCRE2POSIX_EXP_DECL size_t regerror(int, const regex_t *, char *, size_t);
|
||||
|
||||
PCRE2POSIX_EXP_DECL void pcre2_regfree(regex_t *);
|
||||
PCRE2POSIX_EXP_DECL void regfree(regex_t *);
|
||||
|
||||
#define regcomp pcre2_regcomp
|
||||
#define regexec pcre2_regexec
|
||||
#define regerror pcre2_regerror
|
||||
#define regfree pcre2_regfree
|
||||
|
||||
/* Debian had a patch that used different names. These are now here to save
|
||||
them having to maintain their own patch, but are not documented by PCRE2. */
|
||||
|
||||
#define PCRE2regcomp pcre2_regcomp
|
||||
#define PCRE2regexec pcre2_regexec
|
||||
#define PCRE2regerror pcre2_regerror
|
||||
#define PCRE2regfree pcre2_regfree
|
||||
|
||||
#ifdef __cplusplus
|
||||
} /* extern "C" */
|
||||
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Loading…
Reference in New Issue