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diff --git a/plugins/Pcre16/docs/doc/pcrebuild.3 b/plugins/Pcre16/docs/doc/pcrebuild.3 deleted file mode 100644 index 403f2ae32f..0000000000 --- a/plugins/Pcre16/docs/doc/pcrebuild.3 +++ /dev/null @@ -1,550 +0,0 @@ -.TH PCREBUILD 3 "12 May 2013" "PCRE 8.33" -.SH NAME -PCRE - Perl-compatible regular expressions -. -. -.SH "BUILDING PCRE" -.rs -.sp -PCRE is distributed with a \fBconfigure\fP 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 \fBCMake\fP -instead of \fBconfigure\fP. The text file -.\" HTML <a href="README.txt"> -.\" </a> -\fBREADME\fP -.\" -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 \fBCMake\fP and building "by -hand") in the text file called -.\" HTML <a href="NON-AUTOTOOLS-BUILD.txt"> -.\" </a> -\fBNON-AUTOTOOLS-BUILD\fP. -.\" -You should consult this file as well as the -.\" HTML <a href="README.txt"> -.\" </a> -\fBREADME\fP -.\" -file if you are building in a non-Unix-like environment. -. -. -.SH "PCRE BUILD-TIME OPTIONS" -.rs -.sp -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 \fBconfigure\fP -script, where the optional features are selected or deselected by providing -options to \fBconfigure\fP before running the \fBmake\fP command. However, the -same options can be selected in both Unix-like and non-Unix-like environments -using the GUI facility of \fBcmake-gui\fP if you are using \fBCMake\fP instead -of \fBconfigure\fP to build PCRE. -.P -If you are not using Autotools or \fBCMake\fP, option selection can be done by -editing the \fBconfig.h\fP file, or by passing parameter settings to the -compiler, as described in -.\" HTML <a href="NON-AUTOTOOLS-BUILD.txt"> -.\" </a> -\fBNON-AUTOTOOLS-BUILD\fP. -.\" -.P -The complete list of options for \fBconfigure\fP (which includes the standard -ones such as the selection of the installation directory) can be obtained by -running -.sp - ./configure --help -.sp -The following sections include descriptions of options whose names begin with ---enable or --disable. These settings specify changes to the defaults for the -\fBconfigure\fP command. Because of the way that \fBconfigure\fP 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. -. -. -.SH "BUILDING 8-BIT, 16-BIT AND 32-BIT LIBRARIES" -.rs -.sp -By default, a library called \fBlibpcre\fP 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 \fBlibpcre16\fP, 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 -.sp - --enable-pcre16 -.sp -to the \fBconfigure\fP command. You can also build yet another separate -library, called \fBlibpcre32\fP, 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 -.sp - --enable-pcre32 -.sp -to the \fBconfigure\fP command. If you do not want the 8-bit library, add -.sp - --disable-pcre8 -.sp -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 \fBpcregrep\fP is -an 8-bit program. None of these are built if you select only the 16-bit or -32-bit libraries. -. -. -.SH "BUILDING SHARED AND STATIC LIBRARIES" -.rs -.sp -The Autotools PCRE building process uses \fBlibtool\fP to build both shared and -static libraries by default. You can suppress one of these by adding one of -.sp - --disable-shared - --disable-static -.sp -to the \fBconfigure\fP command, as required. -. -. -.SH "C++ SUPPORT" -.rs -.sp -By default, if the 8-bit library is being built, the \fBconfigure\fP 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 -.sp - --disable-cpp -.sp -to the \fBconfigure\fP command. -. -. -.SH "UTF-8, UTF-16 AND UTF-32 SUPPORT" -.rs -.sp -To build PCRE with support for UTF Unicode character strings, add -.sp - --enable-utf -.sp -to the \fBconfigure\fP 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 -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 -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. -. -. -.SH "UNICODE CHARACTER PROPERTY SUPPORT" -.rs -.sp -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 \eP, \ep, and \eX, which refer to Unicode -character properties, you must add -.sp - --enable-unicode-properties -.sp -to the \fBconfigure\fP command. This implies UTF support, even if you have -not explicitly requested it. -.P -Including Unicode property support adds around 30K of tables to the PCRE -library. Only the general category properties such as \fILu\fP and \fINd\fP are -supported. Details are given in the -.\" HREF -\fBpcrepattern\fP -.\" -documentation. -. -. -.SH "JUST-IN-TIME COMPILER SUPPORT" -.rs -.sp -Just-in-time compiler support is included in the build by specifying -.sp - --enable-jit -.sp -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 -.\" HREF -\fBpcrejit\fP -.\" -documentation for a discussion of JIT usage. When JIT support is enabled, -pcregrep automatically makes use of it, unless you add -.sp - --disable-pcregrep-jit -.sp -to the "configure" command. -. -. -.SH "CODE VALUE OF NEWLINE" -.rs -.sp -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 -.sp - --enable-newline-is-cr -.sp -to the \fBconfigure\fP command. There is also a --enable-newline-is-lf option, -which explicitly specifies linefeed as the newline character. -.sp -Alternatively, you can specify that line endings are to be indicated by the two -character sequence CRLF. If you want this, add -.sp - --enable-newline-is-crlf -.sp -to the \fBconfigure\fP command. There is a fourth option, specified by -.sp - --enable-newline-is-anycrlf -.sp -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 -.sp - --enable-newline-is-any -.sp -causes PCRE to recognize any Unicode newline sequence. -.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. -. -. -.SH "WHAT \eR MATCHES" -.rs -.sp -By default, the sequence \eR in a pattern matches any Unicode newline sequence, -whatever has been selected as the line ending sequence. If you specify -.sp - --enable-bsr-anycrlf -.sp -the default is changed so that \eR matches only CR, LF, or CRLF. Whatever is -selected when PCRE is built can be overridden when the library functions are -called. -. -. -.SH "POSIX MALLOC USAGE" -.rs -.sp -When the 8-bit library is called through the POSIX interface (see the -.\" HREF -\fBpcreposix\fP -.\" -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 \fBmalloc()\fP 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 -.sp - --with-posix-malloc-threshold=20 -.sp -to the \fBconfigure\fP command. -. -. -.SH "HANDLING VERY LARGE PATTERNS" -.rs -.sp -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 -.sp - --with-link-size=3 -.sp -to the \fBconfigure\fP 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. -. -. -.SH "AVOIDING EXCESSIVE STACK USAGE" -.rs -.sp -When matching with the \fBpcre_exec()\fP function, PCRE implements backtracking -by making recursive calls to an internal function called \fBmatch()\fP. 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 -.\" HREF -\fBpcrestack\fP -.\" -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 -.sp - --disable-stack-for-recursion -.sp -to the \fBconfigure\fP command. With this configuration, PCRE will use the -\fBpcre_stack_malloc\fP and \fBpcre_stack_free\fP variables to call memory -management functions. By default these point to \fBmalloc()\fP and -\fBfree()\fP, but you can replace the pointers so that your own functions are -used instead. -.P -Separate functions are provided rather than using \fBpcre_malloc\fP and -\fBpcre_free\fP 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 \fBmalloc()\fP and \fBfree()\fP. PCRE runs noticeably more -slowly when built in this way. This option affects only the \fBpcre_exec()\fP -function; it is not relevant for \fBpcre_dfa_exec()\fP. -. -. -.SH "LIMITING PCRE RESOURCE USAGE" -.rs -.sp -Internally, PCRE has a function called \fBmatch()\fP, which it calls repeatedly -(sometimes recursively) when matching a pattern with the \fBpcre_exec()\fP -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 \fBpcre_exec()\fP. The limit can be changed -at run time, as described in the -.\" HREF -\fBpcreapi\fP -.\" -documentation. The default is 10 million, but this can be changed by adding a -setting such as -.sp - --with-match-limit=500000 -.sp -to the \fBconfigure\fP command. This setting has no effect on the -\fBpcre_dfa_exec()\fP matching function. -.P -In some environments it is desirable to limit the depth of recursive calls of -\fBmatch()\fP 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, -.sp - --with-match-limit-recursion=10000 -.sp -to the \fBconfigure\fP command. This value can also be overridden at run time. -. -. -.SH "CREATING CHARACTER TABLES AT BUILD TIME" -.rs -.sp -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 \fIpcre_chartables.c.dist\fP. These tables are for ASCII codes -only. If you add -.sp - --enable-rebuild-chartables -.sp -to the \fBconfigure\fP command, the distributed tables are no longer used. -Instead, a program called \fBdftables\fP 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 \fBdftables\fP is run on the local host. If you need to -create alternative tables when cross compiling, you will have to do so "by -hand".) -. -. -.SH "USING EBCDIC CODE" -.rs -.sp -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 -.sp - --enable-ebcdic -.sp -to the \fBconfigure\fP 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 -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 -.sp - --enable-ebcdic-nl25 -.sp -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 \fInot\fP -chosen as LF is made to correspond to the Unicode NEL character (which, in -Unicode, is 0x85). -.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. -. -. -.SH "PCREGREP OPTIONS FOR COMPRESSED FILE SUPPORT" -.rs -.sp -By default, \fBpcregrep\fP reads all files as plain text. You can build it so -that it recognizes files whose names end in \fB.gz\fP or \fB.bz2\fP, and reads -them with \fBlibz\fP or \fBlibbz2\fP, respectively, by adding one or both of -.sp - --enable-pcregrep-libz - --enable-pcregrep-libbz2 -.sp -to the \fBconfigure\fP command. These options naturally require that the -relevant libraries are installed on your system. Configuration will fail if -they are not. -. -. -.SH "PCREGREP BUFFER SIZE" -.rs -.sp -\fBpcregrep\fP 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, -.sp - --with-pcregrep-bufsize=50K -.sp -to the \fBconfigure\fP command. The caller of \fPpcregrep\fP can, however, -override this value by specifying a run-time option. -. -. -.SH "PCRETEST OPTION FOR LIBREADLINE SUPPORT" -.rs -.sp -If you add -.sp - --enable-pcretest-libreadline -.sp -to the \fBconfigure\fP command, \fBpcretest\fP is linked with the -\fBlibreadline\fP library, and when its input is from a terminal, it reads it -using the \fBreadline()\fP function. This provides line-editing and history -facilities. Note that \fBlibreadline\fP is GPL-licensed, so if you distribute a -binary of \fBpcretest\fP linked in this way, there may be licensing issues. -.P -Setting this option causes the \fB-lreadline\fP option to be added to the -\fBpcretest\fP build. In many operating environments with a sytem-installed -\fBlibreadline\fP 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 \fBlibreadline\fP says -this: -.sp - "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." -.sp -If your environment has not been set up so that an appropriate library is -automatically included, you may need to add something like -.sp - LIBS="-ncurses" -.sp -immediately before the \fBconfigure\fP command. -. -. -.SH "DEBUGGING WITH VALGRIND SUPPORT" -.rs -.sp -By adding the -.sp - --enable-valgrind -.sp -option to to the \fBconfigure\fP 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. -. -. -.SH "CODE COVERAGE REPORTING" -.rs -.sp -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 -\fBlcov\fP version 1.6 or above. Then specify -.sp - --enable-coverage -.sp -to the \fBconfigure\fP command and build PCRE in the usual way. -.P -Note that using \fBccache\fP (a caching C compiler) is incompatible with code -coverage reporting. If you have configured \fBccache\fP to run automatically -on your system, you must set the environment variable -.sp - CCACHE_DISABLE=1 -.sp -before running \fBmake\fP to build PCRE, so that \fBccache\fP is not used. -.P -When --enable-coverage is used, the following addition targets are added to the -\fIMakefile\fP: -.sp - make coverage -.sp -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". -.sp - make coverage-reset -.sp -This zeroes the coverage counters, but does nothing else. -.sp - make coverage-baseline -.sp -This captures baseline coverage information. -.sp - make coverage-report -.sp -This creates the coverage report. -.sp - make coverage-clean-report -.sp -This removes the generated coverage report without cleaning the coverage data -itself. -.sp - make coverage-clean-data -.sp -This removes the captured coverage data without removing the coverage files -created at compile time (*.gcno). -.sp - make coverage-clean -.sp -This cleans all coverage data including the generated coverage report. For more -information about code coverage, see the \fBgcov\fP and \fBlcov\fP -documentation. -. -. -.SH "SEE ALSO" -.rs -.sp -\fBpcreapi\fP(3), \fBpcre16\fP, \fBpcre32\fP, \fBpcre_config\fP(3). -. -. -.SH AUTHOR -.rs -.sp -.nf -Philip Hazel -University Computing Service -Cambridge CB2 3QH, England. -.fi -. -. -.SH REVISION -.rs -.sp -.nf -Last updated: 12 May 2013 -Copyright (c) 1997-2013 University of Cambridge. -.fi |