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diff --git a/plugins/Pcre16/docs/doc/html/pcrebuild.html b/plugins/Pcre16/docs/doc/html/pcrebuild.html new file mode 100644 index 0000000000..03c8cbe0b2 --- /dev/null +++ b/plugins/Pcre16/docs/doc/html/pcrebuild.html @@ -0,0 +1,534 @@ +<html> +<head> +<title>pcrebuild specification</title> +</head> +<body bgcolor="#FFFFFF" text="#00005A" link="#0066FF" alink="#3399FF" vlink="#2222BB"> +<h1>pcrebuild man page</h1> +<p> +Return to the <a href="index.html">PCRE index page</a>. +</p> +<p> +This page is part of the PCRE HTML documentation. It was generated automatically +from the original man page. If there is any nonsense in it, please consult the +man page, in case the conversion went wrong. +<br> +<ul> +<li><a name="TOC1" href="#SEC1">BUILDING PCRE</a> +<li><a name="TOC2" href="#SEC2">PCRE BUILD-TIME OPTIONS</a> +<li><a name="TOC3" href="#SEC3">BUILDING 8-BIT, 16-BIT AND 32-BIT LIBRARIES</a> +<li><a name="TOC4" href="#SEC4">BUILDING SHARED AND STATIC LIBRARIES</a> +<li><a name="TOC5" href="#SEC5">C++ SUPPORT</a> +<li><a name="TOC6" href="#SEC6">UTF-8, UTF-16 AND UTF-32 SUPPORT</a> +<li><a name="TOC7" href="#SEC7">UNICODE CHARACTER PROPERTY SUPPORT</a> +<li><a name="TOC8" href="#SEC8">JUST-IN-TIME COMPILER SUPPORT</a> +<li><a name="TOC9" href="#SEC9">CODE VALUE OF NEWLINE</a> +<li><a name="TOC10" href="#SEC10">WHAT \R MATCHES</a> +<li><a name="TOC11" href="#SEC11">POSIX MALLOC USAGE</a> +<li><a name="TOC12" href="#SEC12">HANDLING VERY LARGE PATTERNS</a> +<li><a name="TOC13" href="#SEC13">AVOIDING EXCESSIVE STACK USAGE</a> +<li><a name="TOC14" href="#SEC14">LIMITING PCRE RESOURCE USAGE</a> +<li><a name="TOC15" href="#SEC15">CREATING CHARACTER TABLES AT BUILD TIME</a> +<li><a name="TOC16" href="#SEC16">USING EBCDIC CODE</a> +<li><a name="TOC17" href="#SEC17">PCREGREP OPTIONS FOR COMPRESSED FILE SUPPORT</a> +<li><a name="TOC18" href="#SEC18">PCREGREP BUFFER SIZE</a> +<li><a name="TOC19" href="#SEC19">PCRETEST OPTION FOR LIBREADLINE SUPPORT</a> +<li><a name="TOC20" href="#SEC20">DEBUGGING WITH VALGRIND SUPPORT</a> +<li><a name="TOC21" href="#SEC21">CODE COVERAGE REPORTING</a> +<li><a name="TOC22" href="#SEC22">SEE ALSO</a> +<li><a name="TOC23" href="#SEC23">AUTHOR</a> +<li><a name="TOC24" href="#SEC24">REVISION</a> +</ul> +<br><a name="SEC1" href="#TOC1">BUILDING PCRE</a><br> +<P> +PCRE is distributed with a <b>configure</b> script that can be used to build the +library in Unix-like environments using the applications known as Autotools. +Also in the distribution are files to support building using <b>CMake</b> +instead of <b>configure</b>. The text file +<a href="README.txt"><b>README</b></a> +contains general information about building with Autotools (some of which is +repeated below), and also has some comments about building on various operating +systems. There is a lot more information about building PCRE without using +Autotools (including information about using <b>CMake</b> and building "by +hand") in the text file called +<a href="NON-AUTOTOOLS-BUILD.txt"><b>NON-AUTOTOOLS-BUILD</b>.</a> +You should consult this file as well as the +<a href="README.txt"><b>README</b></a> +file if you are building in a non-Unix-like environment. +</P> +<br><a name="SEC2" href="#TOC1">PCRE BUILD-TIME OPTIONS</a><br> +<P> +The rest of this document describes the optional features of PCRE that can be +selected when the library is compiled. It assumes use of the <b>configure</b> +script, where the optional features are selected or deselected by providing +options to <b>configure</b> before running the <b>make</b> command. However, the +same options can be selected in both Unix-like and non-Unix-like environments +using the GUI facility of <b>cmake-gui</b> if you are using <b>CMake</b> instead +of <b>configure</b> to build PCRE. +</P> +<P> +If you are not using Autotools or <b>CMake</b>, option selection can be done by +editing the <b>config.h</b> file, or by passing parameter settings to the +compiler, as described in +<a href="NON-AUTOTOOLS-BUILD.txt"><b>NON-AUTOTOOLS-BUILD</b>.</a> +</P> +<P> +The complete list of options for <b>configure</b> (which includes the standard +ones such as the selection of the installation directory) can be obtained by +running +<pre> + ./configure --help +</pre> +The following sections include descriptions of options whose names begin with +--enable or --disable. These settings specify changes to the defaults for the +<b>configure</b> command. Because of the way that <b>configure</b> works, +--enable and --disable always come in pairs, so the complementary option always +exists as well, but as it specifies the default, it is not described. +</P> +<br><a name="SEC3" href="#TOC1">BUILDING 8-BIT, 16-BIT AND 32-BIT LIBRARIES</a><br> +<P> +By default, a library called <b>libpcre</b> is built, containing functions that +take string arguments contained in vectors of bytes, either as single-byte +characters, or interpreted as UTF-8 strings. You can also build a separate +library, called <b>libpcre16</b>, in which strings are contained in vectors of +16-bit data units and interpreted either as single-unit characters or UTF-16 +strings, by adding +<pre> + --enable-pcre16 +</pre> +to the <b>configure</b> command. You can also build yet another separate +library, called <b>libpcre32</b>, in which strings are contained in vectors of +32-bit data units and interpreted either as single-unit characters or UTF-32 +strings, by adding +<pre> + --enable-pcre32 +</pre> +to the <b>configure</b> command. If you do not want the 8-bit library, add +<pre> + --disable-pcre8 +</pre> +as well. At least one of the three libraries must be built. Note that the C++ +and POSIX wrappers are for the 8-bit library only, and that <b>pcregrep</b> is +an 8-bit program. None of these are built if you select only the 16-bit or +32-bit libraries. +</P> +<br><a name="SEC4" href="#TOC1">BUILDING SHARED AND STATIC LIBRARIES</a><br> +<P> +The Autotools PCRE building process uses <b>libtool</b> to build both shared and +static libraries by default. You can suppress one of these by adding one of +<pre> + --disable-shared + --disable-static +</pre> +to the <b>configure</b> command, as required. +</P> +<br><a name="SEC5" href="#TOC1">C++ SUPPORT</a><br> +<P> +By default, if the 8-bit library is being built, the <b>configure</b> script +will search for a C++ compiler and C++ header files. If it finds them, it +automatically builds the C++ wrapper library (which supports only 8-bit +strings). You can disable this by adding +<pre> + --disable-cpp +</pre> +to the <b>configure</b> command. +</P> +<br><a name="SEC6" href="#TOC1">UTF-8, UTF-16 AND UTF-32 SUPPORT</a><br> +<P> +To build PCRE with support for UTF Unicode character strings, add +<pre> + --enable-utf +</pre> +to the <b>configure</b> command. This setting applies to all three libraries, +adding support for UTF-8 to the 8-bit library, support for UTF-16 to the 16-bit +library, and support for UTF-32 to the to the 32-bit library. There are no +separate options for enabling UTF-8, UTF-16 and UTF-32 independently because +that would allow ridiculous settings such as requesting UTF-16 support while +building only the 8-bit library. It is not possible to build one library with +UTF support and another without in the same configuration. (For backwards +compatibility, --enable-utf8 is a synonym of --enable-utf.) +</P> +<P> +Of itself, this setting does not make PCRE treat strings as UTF-8, UTF-16 or +UTF-32. As well as compiling PCRE with this option, you also have have to set +the PCRE_UTF8, PCRE_UTF16 or PCRE_UTF32 option (as appropriate) when you call +one of the pattern compiling functions. +</P> +<P> +If you set --enable-utf when compiling in an EBCDIC environment, PCRE expects +its input to be either ASCII or UTF-8 (depending on the run-time option). It is +not possible to support both EBCDIC and UTF-8 codes in the same version of the +library. Consequently, --enable-utf and --enable-ebcdic are mutually +exclusive. +</P> +<br><a name="SEC7" href="#TOC1">UNICODE CHARACTER PROPERTY SUPPORT</a><br> +<P> +UTF support allows the libraries to process character codepoints up to 0x10ffff +in the strings that they handle. On its own, however, it does not provide any +facilities for accessing the properties of such characters. If you want to be +able to use the pattern escapes \P, \p, and \X, which refer to Unicode +character properties, you must add +<pre> + --enable-unicode-properties +</pre> +to the <b>configure</b> command. This implies UTF support, even if you have +not explicitly requested it. +</P> +<P> +Including Unicode property support adds around 30K of tables to the PCRE +library. Only the general category properties such as <i>Lu</i> and <i>Nd</i> are +supported. Details are given in the +<a href="pcrepattern.html"><b>pcrepattern</b></a> +documentation. +</P> +<br><a name="SEC8" href="#TOC1">JUST-IN-TIME COMPILER SUPPORT</a><br> +<P> +Just-in-time compiler support is included in the build by specifying +<pre> + --enable-jit +</pre> +This support is available only for certain hardware architectures. If this +option is set for an unsupported architecture, a compile time error occurs. +See the +<a href="pcrejit.html"><b>pcrejit</b></a> +documentation for a discussion of JIT usage. When JIT support is enabled, +pcregrep automatically makes use of it, unless you add +<pre> + --disable-pcregrep-jit +</pre> +to the "configure" command. +</P> +<br><a name="SEC9" href="#TOC1">CODE VALUE OF NEWLINE</a><br> +<P> +By default, PCRE interprets the linefeed (LF) character as indicating the end +of a line. This is the normal newline character on Unix-like systems. You can +compile PCRE to use carriage return (CR) instead, by adding +<pre> + --enable-newline-is-cr +</pre> +to the <b>configure</b> command. There is also a --enable-newline-is-lf option, +which explicitly specifies linefeed as the newline character. +<br> +<br> +Alternatively, you can specify that line endings are to be indicated by the two +character sequence CRLF. If you want this, add +<pre> + --enable-newline-is-crlf +</pre> +to the <b>configure</b> command. There is a fourth option, specified by +<pre> + --enable-newline-is-anycrlf +</pre> +which causes PCRE to recognize any of the three sequences CR, LF, or CRLF as +indicating a line ending. Finally, a fifth option, specified by +<pre> + --enable-newline-is-any +</pre> +causes PCRE to recognize any Unicode newline sequence. +</P> +<P> +Whatever line ending convention is selected when PCRE is built can be +overridden when the library functions are called. At build time it is +conventional to use the standard for your operating system. +</P> +<br><a name="SEC10" href="#TOC1">WHAT \R MATCHES</a><br> +<P> +By default, the sequence \R in a pattern matches any Unicode newline sequence, +whatever has been selected as the line ending sequence. If you specify +<pre> + --enable-bsr-anycrlf +</pre> +the default is changed so that \R matches only CR, LF, or CRLF. Whatever is +selected when PCRE is built can be overridden when the library functions are +called. +</P> +<br><a name="SEC11" href="#TOC1">POSIX MALLOC USAGE</a><br> +<P> +When the 8-bit library is called through the POSIX interface (see the +<a href="pcreposix.html"><b>pcreposix</b></a> +documentation), additional working storage is required for holding the pointers +to capturing substrings, because PCRE requires three integers per substring, +whereas the POSIX interface provides only two. If the number of expected +substrings is small, the wrapper function uses space on the stack, because this +is faster than using <b>malloc()</b> for each call. The default threshold above +which the stack is no longer used is 10; it can be changed by adding a setting +such as +<pre> + --with-posix-malloc-threshold=20 +</pre> +to the <b>configure</b> command. +</P> +<br><a name="SEC12" href="#TOC1">HANDLING VERY LARGE PATTERNS</a><br> +<P> +Within a compiled pattern, offset values are used to point from one part to +another (for example, from an opening parenthesis to an alternation +metacharacter). By default, in the 8-bit and 16-bit libraries, two-byte values +are used for these offsets, leading to a maximum size for a compiled pattern of +around 64K. This is sufficient to handle all but the most gigantic patterns. +Nevertheless, some people do want to process truly enormous patterns, so it is +possible to compile PCRE to use three-byte or four-byte offsets by adding a +setting such as +<pre> + --with-link-size=3 +</pre> +to the <b>configure</b> command. The value given must be 2, 3, or 4. For the +16-bit library, a value of 3 is rounded up to 4. In these libraries, using +longer offsets slows down the operation of PCRE because it has to load +additional data when handling them. For the 32-bit library the value is always +4 and cannot be overridden; the value of --with-link-size is ignored. +</P> +<br><a name="SEC13" href="#TOC1">AVOIDING EXCESSIVE STACK USAGE</a><br> +<P> +When matching with the <b>pcre_exec()</b> function, PCRE implements backtracking +by making recursive calls to an internal function called <b>match()</b>. In +environments where the size of the stack is limited, this can severely limit +PCRE's operation. (The Unix environment does not usually suffer from this +problem, but it may sometimes be necessary to increase the maximum stack size. +There is a discussion in the +<a href="pcrestack.html"><b>pcrestack</b></a> +documentation.) An alternative approach to recursion that uses memory from the +heap to remember data, instead of using recursive function calls, has been +implemented to work round the problem of limited stack size. If you want to +build a version of PCRE that works this way, add +<pre> + --disable-stack-for-recursion +</pre> +to the <b>configure</b> command. With this configuration, PCRE will use the +<b>pcre_stack_malloc</b> and <b>pcre_stack_free</b> variables to call memory +management functions. By default these point to <b>malloc()</b> and +<b>free()</b>, but you can replace the pointers so that your own functions are +used instead. +</P> +<P> +Separate functions are provided rather than using <b>pcre_malloc</b> and +<b>pcre_free</b> because the usage is very predictable: the block sizes +requested are always the same, and the blocks are always freed in reverse +order. A calling program might be able to implement optimized functions that +perform better than <b>malloc()</b> and <b>free()</b>. PCRE runs noticeably more +slowly when built in this way. This option affects only the <b>pcre_exec()</b> +function; it is not relevant for <b>pcre_dfa_exec()</b>. +</P> +<br><a name="SEC14" href="#TOC1">LIMITING PCRE RESOURCE USAGE</a><br> +<P> +Internally, PCRE has a function called <b>match()</b>, which it calls repeatedly +(sometimes recursively) when matching a pattern with the <b>pcre_exec()</b> +function. By controlling the maximum number of times this function may be +called during a single matching operation, a limit can be placed on the +resources used by a single call to <b>pcre_exec()</b>. The limit can be changed +at run time, as described in the +<a href="pcreapi.html"><b>pcreapi</b></a> +documentation. The default is 10 million, but this can be changed by adding a +setting such as +<pre> + --with-match-limit=500000 +</pre> +to the <b>configure</b> command. This setting has no effect on the +<b>pcre_dfa_exec()</b> matching function. +</P> +<P> +In some environments it is desirable to limit the depth of recursive calls of +<b>match()</b> more strictly than the total number of calls, in order to +restrict the maximum amount of stack (or heap, if --disable-stack-for-recursion +is specified) that is used. A second limit controls this; it defaults to the +value that is set for --with-match-limit, which imposes no additional +constraints. However, you can set a lower limit by adding, for example, +<pre> + --with-match-limit-recursion=10000 +</pre> +to the <b>configure</b> command. This value can also be overridden at run time. +</P> +<br><a name="SEC15" href="#TOC1">CREATING CHARACTER TABLES AT BUILD TIME</a><br> +<P> +PCRE uses fixed tables for processing characters whose code values are less +than 256. By default, PCRE is built with a set of tables that are distributed +in the file <i>pcre_chartables.c.dist</i>. These tables are for ASCII codes +only. If you add +<pre> + --enable-rebuild-chartables +</pre> +to the <b>configure</b> command, the distributed tables are no longer used. +Instead, a program called <b>dftables</b> is compiled and run. This outputs the +source for new set of tables, created in the default locale of your C run-time +system. (This method of replacing the tables does not work if you are cross +compiling, because <b>dftables</b> is run on the local host. If you need to +create alternative tables when cross compiling, you will have to do so "by +hand".) +</P> +<br><a name="SEC16" href="#TOC1">USING EBCDIC CODE</a><br> +<P> +PCRE assumes by default that it will run in an environment where the character +code is ASCII (or Unicode, which is a superset of ASCII). This is the case for +most computer operating systems. PCRE can, however, be compiled to run in an +EBCDIC environment by adding +<pre> + --enable-ebcdic +</pre> +to the <b>configure</b> command. This setting implies +--enable-rebuild-chartables. You should only use it if you know that you are in +an EBCDIC environment (for example, an IBM mainframe operating system). The +--enable-ebcdic option is incompatible with --enable-utf. +</P> +<P> +The EBCDIC character that corresponds to an ASCII LF is assumed to have the +value 0x15 by default. However, in some EBCDIC environments, 0x25 is used. In +such an environment you should use +<pre> + --enable-ebcdic-nl25 +</pre> +as well as, or instead of, --enable-ebcdic. The EBCDIC character for CR has the +same value as in ASCII, namely, 0x0d. Whichever of 0x15 and 0x25 is <i>not</i> +chosen as LF is made to correspond to the Unicode NEL character (which, in +Unicode, is 0x85). +</P> +<P> +The options that select newline behaviour, such as --enable-newline-is-cr, +and equivalent run-time options, refer to these character values in an EBCDIC +environment. +</P> +<br><a name="SEC17" href="#TOC1">PCREGREP OPTIONS FOR COMPRESSED FILE SUPPORT</a><br> +<P> +By default, <b>pcregrep</b> reads all files as plain text. You can build it so +that it recognizes files whose names end in <b>.gz</b> or <b>.bz2</b>, and reads +them with <b>libz</b> or <b>libbz2</b>, respectively, by adding one or both of +<pre> + --enable-pcregrep-libz + --enable-pcregrep-libbz2 +</pre> +to the <b>configure</b> command. These options naturally require that the +relevant libraries are installed on your system. Configuration will fail if +they are not. +</P> +<br><a name="SEC18" href="#TOC1">PCREGREP BUFFER SIZE</a><br> +<P> +<b>pcregrep</b> uses an internal buffer to hold a "window" on the file it is +scanning, in order to be able to output "before" and "after" lines when it +finds a match. The size of the buffer is controlled by a parameter whose +default value is 20K. The buffer itself is three times this size, but because +of the way it is used for holding "before" lines, the longest line that is +guaranteed to be processable is the parameter size. You can change the default +parameter value by adding, for example, +<pre> + --with-pcregrep-bufsize=50K +</pre> +to the <b>configure</b> command. The caller of \fPpcregrep\fP can, however, +override this value by specifying a run-time option. +</P> +<br><a name="SEC19" href="#TOC1">PCRETEST OPTION FOR LIBREADLINE SUPPORT</a><br> +<P> +If you add +<pre> + --enable-pcretest-libreadline +</pre> +to the <b>configure</b> command, <b>pcretest</b> is linked with the +<b>libreadline</b> library, and when its input is from a terminal, it reads it +using the <b>readline()</b> function. This provides line-editing and history +facilities. Note that <b>libreadline</b> is GPL-licensed, so if you distribute a +binary of <b>pcretest</b> linked in this way, there may be licensing issues. +</P> +<P> +Setting this option causes the <b>-lreadline</b> option to be added to the +<b>pcretest</b> build. In many operating environments with a sytem-installed +<b>libreadline</b> this is sufficient. However, in some environments (e.g. +if an unmodified distribution version of readline is in use), some extra +configuration may be necessary. The INSTALL file for <b>libreadline</b> says +this: +<pre> + "Readline uses the termcap functions, but does not link with the + termcap or curses library itself, allowing applications which link + with readline the to choose an appropriate library." +</pre> +If your environment has not been set up so that an appropriate library is +automatically included, you may need to add something like +<pre> + LIBS="-ncurses" +</pre> +immediately before the <b>configure</b> command. +</P> +<br><a name="SEC20" href="#TOC1">DEBUGGING WITH VALGRIND SUPPORT</a><br> +<P> +By adding the +<pre> + --enable-valgrind +</pre> +option to to the <b>configure</b> command, PCRE will use valgrind annotations +to mark certain memory regions as unaddressable. This allows it to detect +invalid memory accesses, and is mostly useful for debugging PCRE itself. +</P> +<br><a name="SEC21" href="#TOC1">CODE COVERAGE REPORTING</a><br> +<P> +If your C compiler is gcc, you can build a version of PCRE that can generate a +code coverage report for its test suite. To enable this, you must install +<b>lcov</b> version 1.6 or above. Then specify +<pre> + --enable-coverage +</pre> +to the <b>configure</b> command and build PCRE in the usual way. +</P> +<P> +Note that using <b>ccache</b> (a caching C compiler) is incompatible with code +coverage reporting. If you have configured <b>ccache</b> to run automatically +on your system, you must set the environment variable +<pre> + CCACHE_DISABLE=1 +</pre> +before running <b>make</b> to build PCRE, so that <b>ccache</b> is not used. +</P> +<P> +When --enable-coverage is used, the following addition targets are added to the +<i>Makefile</i>: +<pre> + make coverage +</pre> +This creates a fresh coverage report for the PCRE test suite. It is equivalent +to running "make coverage-reset", "make coverage-baseline", "make check", and +then "make coverage-report". +<pre> + make coverage-reset +</pre> +This zeroes the coverage counters, but does nothing else. +<pre> + make coverage-baseline +</pre> +This captures baseline coverage information. +<pre> + make coverage-report +</pre> +This creates the coverage report. +<pre> + make coverage-clean-report +</pre> +This removes the generated coverage report without cleaning the coverage data +itself. +<pre> + make coverage-clean-data +</pre> +This removes the captured coverage data without removing the coverage files +created at compile time (*.gcno). +<pre> + make coverage-clean +</pre> +This cleans all coverage data including the generated coverage report. For more +information about code coverage, see the <b>gcov</b> and <b>lcov</b> +documentation. +</P> +<br><a name="SEC22" href="#TOC1">SEE ALSO</a><br> +<P> +<b>pcreapi</b>(3), <b>pcre16</b>, <b>pcre32</b>, <b>pcre_config</b>(3). +</P> +<br><a name="SEC23" href="#TOC1">AUTHOR</a><br> +<P> +Philip Hazel +<br> +University Computing Service +<br> +Cambridge CB2 3QH, England. +<br> +</P> +<br><a name="SEC24" href="#TOC1">REVISION</a><br> +<P> +Last updated: 12 May 2013 +<br> +Copyright © 1997-2013 University of Cambridge. +<br> +<p> +Return to the <a href="index.html">PCRE index page</a>. +</p> |