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diff --git a/plugins/Pcre16/docs/doc/html/pcreprecompile.html b/plugins/Pcre16/docs/doc/html/pcreprecompile.html deleted file mode 100644 index decb1d6ce0..0000000000 --- a/plugins/Pcre16/docs/doc/html/pcreprecompile.html +++ /dev/null @@ -1,163 +0,0 @@ -<html> -<head> -<title>pcreprecompile specification</title> -</head> -<body bgcolor="#FFFFFF" text="#00005A" link="#0066FF" alink="#3399FF" vlink="#2222BB"> -<h1>pcreprecompile 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">SAVING AND RE-USING PRECOMPILED PCRE PATTERNS</a> -<li><a name="TOC2" href="#SEC2">SAVING A COMPILED PATTERN</a> -<li><a name="TOC3" href="#SEC3">RE-USING A PRECOMPILED PATTERN</a> -<li><a name="TOC4" href="#SEC4">COMPATIBILITY WITH DIFFERENT PCRE RELEASES</a> -<li><a name="TOC5" href="#SEC5">AUTHOR</a> -<li><a name="TOC6" href="#SEC6">REVISION</a> -</ul> -<br><a name="SEC1" href="#TOC1">SAVING AND RE-USING PRECOMPILED PCRE PATTERNS</a><br> -<P> -If you are running an application that uses a large number of regular -expression patterns, it may be useful to store them in a precompiled form -instead of having to compile them every time the application is run. -If you are not using any private character tables (see the -<a href="pcre_maketables.html"><b>pcre_maketables()</b></a> -documentation), this is relatively straightforward. If you are using private -tables, it is a little bit more complicated. However, if you are using the -just-in-time optimization feature, it is not possible to save and reload the -JIT data. -</P> -<P> -If you save compiled patterns to a file, you can copy them to a different host -and run them there. If the two hosts have different endianness (byte order), -you should run the <b>pcre[16|32]_pattern_to_host_byte_order()</b> function on the -new host before trying to match the pattern. The matching functions return -PCRE_ERROR_BADENDIANNESS if they detect a pattern with the wrong endianness. -</P> -<P> -Compiling regular expressions with one version of PCRE for use with a different -version is not guaranteed to work and may cause crashes, and saving and -restoring a compiled pattern loses any JIT optimization data. -</P> -<br><a name="SEC2" href="#TOC1">SAVING A COMPILED PATTERN</a><br> -<P> -The value returned by <b>pcre[16|32]_compile()</b> points to a single block of -memory that holds the compiled pattern and associated data. You can find the -length of this block in bytes by calling <b>pcre[16|32]_fullinfo()</b> with an -argument of PCRE_INFO_SIZE. You can then save the data in any appropriate -manner. Here is sample code for the 8-bit library that compiles a pattern and -writes it to a file. It assumes that the variable <i>fd</i> refers to a file -that is open for output: -<pre> - int erroroffset, rc, size; - char *error; - pcre *re; - - re = pcre_compile("my pattern", 0, &error, &erroroffset, NULL); - if (re == NULL) { ... handle errors ... } - rc = pcre_fullinfo(re, NULL, PCRE_INFO_SIZE, &size); - if (rc < 0) { ... handle errors ... } - rc = fwrite(re, 1, size, fd); - if (rc != size) { ... handle errors ... } -</pre> -In this example, the bytes that comprise the compiled pattern are copied -exactly. Note that this is binary data that may contain any of the 256 possible -byte values. On systems that make a distinction between binary and non-binary -data, be sure that the file is opened for binary output. -</P> -<P> -If you want to write more than one pattern to a file, you will have to devise a -way of separating them. For binary data, preceding each pattern with its length -is probably the most straightforward approach. Another possibility is to write -out the data in hexadecimal instead of binary, one pattern to a line. -</P> -<P> -Saving compiled patterns in a file is only one possible way of storing them for -later use. They could equally well be saved in a database, or in the memory of -some daemon process that passes them via sockets to the processes that want -them. -</P> -<P> -If the pattern has been studied, it is also possible to save the normal study -data in a similar way to the compiled pattern itself. However, if the -PCRE_STUDY_JIT_COMPILE was used, the just-in-time data that is created cannot -be saved because it is too dependent on the current environment. When studying -generates additional information, <b>pcre[16|32]_study()</b> returns a pointer to a -<b>pcre[16|32]_extra</b> data block. Its format is defined in the -<a href="pcreapi.html#extradata">section on matching a pattern</a> -in the -<a href="pcreapi.html"><b>pcreapi</b></a> -documentation. The <i>study_data</i> field points to the binary study data, and -this is what you must save (not the <b>pcre[16|32]_extra</b> block itself). The -length of the study data can be obtained by calling <b>pcre[16|32]_fullinfo()</b> -with an argument of PCRE_INFO_STUDYSIZE. Remember to check that -<b>pcre[16|32]_study()</b> did return a non-NULL value before trying to save the -study data. -</P> -<br><a name="SEC3" href="#TOC1">RE-USING A PRECOMPILED PATTERN</a><br> -<P> -Re-using a precompiled pattern is straightforward. Having reloaded it into main -memory, called <b>pcre[16|32]_pattern_to_host_byte_order()</b> if necessary, you -pass its pointer to <b>pcre[16|32]_exec()</b> or <b>pcre[16|32]_dfa_exec()</b> in -the usual way. -</P> -<P> -However, if you passed a pointer to custom character tables when the pattern -was compiled (the <i>tableptr</i> argument of <b>pcre[16|32]_compile()</b>), you -must now pass a similar pointer to <b>pcre[16|32]_exec()</b> or -<b>pcre[16|32]_dfa_exec()</b>, because the value saved with the compiled pattern -will obviously be nonsense. A field in a <b>pcre[16|32]_extra()</b> block is used -to pass this data, as described in the -<a href="pcreapi.html#extradata">section on matching a pattern</a> -in the -<a href="pcreapi.html"><b>pcreapi</b></a> -documentation. -</P> -<P> -<b>Warning:</b> The tables that <b>pcre_exec()</b> and <b>pcre_dfa_exec()</b> use -must be the same as those that were used when the pattern was compiled. If this -is not the case, the behaviour is undefined. -</P> -<P> -If you did not provide custom character tables when the pattern was compiled, -the pointer in the compiled pattern is NULL, which causes the matching -functions to use PCRE's internal tables. Thus, you do not need to take any -special action at run time in this case. -</P> -<P> -If you saved study data with the compiled pattern, you need to create your own -<b>pcre[16|32]_extra</b> data block and set the <i>study_data</i> field to point -to the reloaded study data. You must also set the PCRE_EXTRA_STUDY_DATA bit in -the <i>flags</i> field to indicate that study data is present. Then pass the -<b>pcre[16|32]_extra</b> block to the matching function in the usual way. If the -pattern was studied for just-in-time optimization, that data cannot be saved, -and so is lost by a save/restore cycle. -</P> -<br><a name="SEC4" href="#TOC1">COMPATIBILITY WITH DIFFERENT PCRE RELEASES</a><br> -<P> -In general, it is safest to recompile all saved patterns when you update to a -new PCRE release, though not all updates actually require this. -</P> -<br><a name="SEC5" href="#TOC1">AUTHOR</a><br> -<P> -Philip Hazel -<br> -University Computing Service -<br> -Cambridge CB2 3QH, England. -<br> -</P> -<br><a name="SEC6" href="#TOC1">REVISION</a><br> -<P> -Last updated: 12 November 2013 -<br> -Copyright © 1997-2013 University of Cambridge. -<br> -<p> -Return to the <a href="index.html">PCRE index page</a>. -</p> |