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diff --git a/ext/pcre/pcrelib/README b/ext/pcre/pcrelib/README deleted file mode 100644 index 879ba04f48..0000000000 --- a/ext/pcre/pcrelib/README +++ /dev/null @@ -1,365 +0,0 @@ -README file for PCRE (Perl-compatible regular expression library) ------------------------------------------------------------------ - -The latest release of PCRE is always available from - - ftp://ftp.csx.cam.ac.uk/pub/software/programming/pcre/pcre-xxx.tar.gz - -Please read the NEWS file if you are upgrading from a previous release. - -PCRE has its own native API, but a set of "wrapper" functions that are based on -the POSIX API are also supplied in the library libpcreposix. Note that this -just provides a POSIX calling interface to PCRE: the regular expressions -themselves still follow Perl syntax and semantics. The header file -for the POSIX-style functions is called pcreposix.h. The official POSIX name is -regex.h, but I didn't want to risk possible problems with existing files of -that name by distributing it that way. To use it with an existing program that -uses the POSIX API, it will have to be renamed or pointed at by a link. - -If you are using the POSIX interface to PCRE and there is already a POSIX regex -library installed on your system, you must take care when linking programs to -ensure that they link with PCRE's libpcreposix library. Otherwise they may pick -up the "real" POSIX functions of the same name. - - -Contributions by users of PCRE ------------------------------- - -You can find contributions from PCRE users in the directory - - ftp://ftp.csx.cam.ac.uk/pub/software/programming/pcre/Contrib - -where there is also a README file giving brief descriptions of what they are. -Several of them provide support for compiling PCRE on various flavours of -Windows systems (I myself do not use Windows). Some are complete in themselves; -others are pointers to URLs containing relevant files. - - -Building PCRE on a Unix-like system ------------------------------------ - -To build PCRE on a Unix-like system, first run the "configure" command from the -PCRE distribution directory, with your current directory set to the directory -where you want the files to be created. This command is a standard GNU -"autoconf" configuration script, for which generic instructions are supplied in -INSTALL. - -Most commonly, people build PCRE within its own distribution directory, and in -this case, on many systems, just running "./configure" is sufficient, but the -usual methods of changing standard defaults are available. For example, - -CFLAGS='-O2 -Wall' ./configure --prefix=/opt/local - -specifies that the C compiler should be run with the flags '-O2 -Wall' instead -of the default, and that "make install" should install PCRE under /opt/local -instead of the default /usr/local. - -If you want to build in a different directory, just run "configure" with that -directory as current. For example, suppose you have unpacked the PCRE source -into /source/pcre/pcre-xxx, but you want to build it in /build/pcre/pcre-xxx: - -cd /build/pcre/pcre-xxx -/source/pcre/pcre-xxx/configure - -There are some optional features that can be included or omitted from the PCRE -library. You can read more about them in the pcrebuild man page. - -. If you want to make use of the support for UTF-8 character strings in PCRE, - you must add --enable-utf8 to the "configure" command. Without it, the code - for handling UTF-8 is not included in the library. (Even when included, it - still has to be enabled by an option at run time.) - -. You can build PCRE to recognized CR or NL as the newline character, instead - of whatever your compiler uses for "\n", by adding --newline-is-cr or - --newline-is-nl to the "configure" command, respectively. Only do this if you - really understand what you are doing. On traditional Unix-like systems, the - newline character is NL. - -. When called via the POSIX interface, PCRE uses malloc() to get additional - storage for processing capturing parentheses if there are more than 10 of - them. You can increase this threshold by setting, for example, - - --with-posix-malloc-threshold=20 - - on the "configure" command. - -. PCRE has a counter which can be set to limit the amount of resources it uses. - If the limit is exceeded during a match, the match fails. The default is ten - million. You can change the default by setting, for example, - - --with-match-limit=500000 - - on the "configure" command. This is just the default; individual calls to - pcre_exec() can supply their own value. There is discussion on the pcreapi - man page. - -. The default maximum compiled pattern size is around 64K. You can increase - this by adding --with-link-size=3 to the "configure" command. You can - increase it even more by setting --with-link-size=4, but this is unlikely - ever to be necessary. If you build PCRE with an increased link size, test 2 - (and 5 if you are using UTF-8) will fail. Part of the output of these tests - is a representation of the compiled pattern, and this changes with the link - size. - -. You can build PCRE so that its match() function does not call itself - recursively. Instead, it uses blocks of data from the heap via special - functions pcre_stack_malloc() and pcre_stack_free() to save data that would - otherwise be saved on the stack. To build PCRE like this, use - - --disable-stack-for-recursion - - on the "configure" command. PCRE runs more slowly in this mode, but it may be - necessary in environments with limited stack sizes. - -The "configure" script builds five files: - -. libtool is a script that builds shared and/or static libraries -. Makefile is built by copying Makefile.in and making substitutions. -. config.h is built by copying config.in and making substitutions. -. pcre-config is built by copying pcre-config.in and making substitutions. -. RunTest is a script for running tests - -Once "configure" has run, you can run "make". It builds two libraries called -libpcre and libpcreposix, a test program called pcretest, and the pcregrep -command. You can use "make install" to copy these, the public header files -pcre.h and pcreposix.h, and the man pages to appropriate live directories on -your system, in the normal way. - -Running "make install" also installs the command pcre-config, which can be used -to recall information about the PCRE configuration and installation. For -example, - - pcre-config --version - -prints the version number, and - - pcre-config --libs - -outputs information about where the library is installed. This command can be -included in makefiles for programs that use PCRE, saving the programmer from -having to remember too many details. - - -Shared libraries on Unix-like systems -------------------------------------- - -The default distribution builds PCRE as two shared libraries and two static -libraries, as long as the operating system supports shared libraries. Shared -library support relies on the "libtool" script which is built as part of the -"configure" process. - -The libtool script is used to compile and link both shared and static -libraries. They are placed in a subdirectory called .libs when they are newly -built. The programs pcretest and pcregrep are built to use these uninstalled -libraries (by means of wrapper scripts in the case of shared libraries). When -you use "make install" to install shared libraries, pcregrep and pcretest are -automatically re-built to use the newly installed shared libraries before being -installed themselves. However, the versions left in the source directory still -use the uninstalled libraries. - -To build PCRE using static libraries only you must use --disable-shared when -configuring it. For example - -./configure --prefix=/usr/gnu --disable-shared - -Then run "make" in the usual way. Similarly, you can use --disable-static to -build only shared libraries. - - -Cross-compiling on a Unix-like system -------------------------------------- - -You can specify CC and CFLAGS in the normal way to the "configure" command, in -order to cross-compile PCRE for some other host. However, during the building -process, the dftables.c source file is compiled *and run* on the local host, in -order to generate the default character tables (the chartables.c file). It -therefore needs to be compiled with the local compiler, not the cross compiler. -You can do this by specifying CC_FOR_BUILD (and if necessary CFLAGS_FOR_BUILD) -when calling the "configure" command. If they are not specified, they default -to the values of CC and CFLAGS. - - -Building on non-Unix systems ----------------------------- - -For a non-Unix system, read the comments in the file NON-UNIX-USE, though if -the system supports the use of "configure" and "make" you may be able to build -PCRE in the same way as for Unix systems. - -PCRE has been compiled on Windows systems and on Macintoshes, but I don't know -the details because I don't use those systems. It should be straightforward to -build PCRE on any system that has a Standard C compiler, because it uses only -Standard C functions. - - -Testing PCRE ------------- - -To test PCRE on a Unix system, run the RunTest script that is created by the -configuring process. (This can also be run by "make runtest", "make check", or -"make test".) For other systems, see the instructions in NON-UNIX-USE. - -The script runs the pcretest test program (which is documented in its own man -page) on each of the testinput files (in the testdata directory) in turn, -and compares the output with the contents of the corresponding testoutput file. -A file called testtry is used to hold the output from pcretest. To run pcretest -on just one of the test files, give its number as an argument to RunTest, for -example: - - RunTest 2 - -The first file can also be fed directly into the perltest script to check that -Perl gives the same results. The only difference you should see is in the first -few lines, where the Perl version is given instead of the PCRE version. - -The second set of tests check pcre_fullinfo(), pcre_info(), pcre_study(), -pcre_copy_substring(), pcre_get_substring(), pcre_get_substring_list(), error -detection, and run-time flags that are specific to PCRE, as well as the POSIX -wrapper API. It also uses the debugging flag to check some of the internals of -pcre_compile(). - -If you build PCRE with a locale setting that is not the standard C locale, the -character tables may be different (see next paragraph). In some cases, this may -cause failures in the second set of tests. For example, in a locale where the -isprint() function yields TRUE for characters in the range 128-255, the use of -[:isascii:] inside a character class defines a different set of characters, and -this shows up in this test as a difference in the compiled code, which is being -listed for checking. Where the comparison test output contains [\x00-\x7f] the -test will contain [\x00-\xff], and similarly in some other cases. This is not a -bug in PCRE. - -The third set of tests checks pcre_maketables(), the facility for building a -set of character tables for a specific locale and using them instead of the -default tables. The tests make use of the "fr_FR" (French) locale. Before -running the test, the script checks for the presence of this locale by running -the "locale" command. If that command fails, or if it doesn't include "fr_FR" -in the list of available locales, the third test cannot be run, and a comment -is output to say why. If running this test produces instances of the error - - ** Failed to set locale "fr_FR" - -in the comparison output, it means that locale is not available on your system, -despite being listed by "locale". This does not mean that PCRE is broken. - -The fourth test checks the UTF-8 support. It is not run automatically unless -PCRE is built with UTF-8 support. To do this you must set --enable-utf8 when -running "configure". This file can be also fed directly to the perltest script, -provided you are running Perl 5.8 or higher. (For Perl 5.6, a small patch, -commented in the script, can be be used.) - -The fifth and final file tests error handling with UTF-8 encoding, and internal -UTF-8 features of PCRE that are not relevant to Perl. - - -Character tables ----------------- - -PCRE uses four tables for manipulating and identifying characters. The final -argument of the pcre_compile() function is a pointer to a block of memory -containing the concatenated tables. A call to pcre_maketables() can be used to -generate a set of tables in the current locale. If the final argument for -pcre_compile() is passed as NULL, a set of default tables that is built into -the binary is used. - -The source file called chartables.c contains the default set of tables. This is -not supplied in the distribution, but is built by the program dftables -(compiled from dftables.c), which uses the ANSI C character handling functions -such as isalnum(), isalpha(), isupper(), islower(), etc. to build the table -sources. This means that the default C locale which is set for your system will -control the contents of these default tables. You can change the default tables -by editing chartables.c and then re-building PCRE. If you do this, you should -probably also edit Makefile to ensure that the file doesn't ever get -re-generated. - -The first two 256-byte tables provide lower casing and case flipping functions, -respectively. The next table consists of three 32-byte bit maps which identify -digits, "word" characters, and white space, respectively. These are used when -building 32-byte bit maps that represent character classes. - -The final 256-byte table has bits indicating various character types, as -follows: - - 1 white space character - 2 letter - 4 decimal digit - 8 hexadecimal digit - 16 alphanumeric or '_' - 128 regular expression metacharacter or binary zero - -You should not alter the set of characters that contain the 128 bit, as that -will cause PCRE to malfunction. - - -Manifest --------- - -The distribution should contain the following files: - -(A) The actual source files of the PCRE library functions and their - headers: - - dftables.c auxiliary program for building chartables.c - get.c ) - maketables.c ) - study.c ) source of - pcre.c ) the functions - pcreposix.c ) - printint.c ) - pcre.in "source" for the header for the external API; pcre.h - is built from this by "configure" - pcreposix.h header for the external POSIX wrapper API - internal.h header for internal use - config.in template for config.h, which is built by configure - -(B) Auxiliary files: - - AUTHORS information about the author of PCRE - ChangeLog log of changes to the code - INSTALL generic installation instructions - LICENCE conditions for the use of PCRE - COPYING the same, using GNU's standard name - Makefile.in template for Unix Makefile, which is built by configure - NEWS important changes in this release - NON-UNIX-USE notes on building PCRE on non-Unix systems - README this file - RunTest.in template for a Unix shell script for running tests - config.guess ) files used by libtool, - config.sub ) used only when building a shared library - configure a configuring shell script (built by autoconf) - configure.in the autoconf input used to build configure - doc/Tech.Notes notes on the encoding - doc/*.3 man page sources for the PCRE functions - doc/*.1 man page sources for pcregrep and pcretest - doc/html/* HTML documentation - doc/pcre.txt plain text version of the man pages - doc/pcretest.txt plain text documentation of test program - doc/perltest.txt plain text documentation of Perl test program - install-sh a shell script for installing files - ltmain.sh file used to build a libtool script - pcretest.c comprehensive test program - pcredemo.c simple demonstration of coding calls to PCRE - perltest Perl test program - pcregrep.c source of a grep utility that uses PCRE - pcre-config.in source of script which retains PCRE information - testdata/testinput1 test data, compatible with Perl - testdata/testinput2 test data for error messages and non-Perl things - testdata/testinput3 test data for locale-specific tests - testdata/testinput4 test data for UTF-8 tests compatible with Perl - testdata/testinput5 test data for other UTF-8 tests - testdata/testoutput1 test results corresponding to testinput1 - testdata/testoutput2 test results corresponding to testinput2 - testdata/testoutput3 test results corresponding to testinput3 - testdata/testoutput4 test results corresponding to testinput4 - testdata/testoutput5 test results corresponding to testinput5 - -(C) Auxiliary files for Win32 DLL - - dll.mk - pcre.def - -(D) Auxiliary file for VPASCAL - - makevp.bat - -Philip Hazel <ph10@cam.ac.uk> -December 2003 |