Skip site navigation (1)Skip section navigation (2)

FreeBSD Manual Pages

  
 
  

home | help
PCRE(3) 		    Library Functions Manual			 PCRE(3)

NAME
     PCRE - Perl-compatible regular expressions

     #include <pcre.h>

PCRE 32-BIT API BASIC FUNCTIONS
     pcre32 *pcre32_compile(PCRE_SPTR32 pattern, int options,
	  const char **errptr, int *erroffset,
	  const unsigned char *tableptr);

     pcre32 *pcre32_compile2(PCRE_SPTR32 pattern, int options,
	  int *errorcodeptr,
	  const unsigned char *tableptr);

     pcre32_extra *pcre32_study(const pcre32 *code, int options,
	  const char **errptr);

     void pcre32_free_study(pcre32_extra *extra);

     int pcre32_exec(const pcre32 *code, const pcre32_extra *extra,
	  PCRE_SPTR32 subject, int length, int startoffset,
	  int options, int *ovector, int ovecsize);

     int pcre32_dfa_exec(const pcre32 *code, const pcre32_extra *extra,
	  PCRE_SPTR32 subject, int length, int startoffset,
	  int options, int *ovector, int ovecsize,
	  int *workspace, int wscount);

PCRE 32-BIT API STRING EXTRACTION FUNCTIONS
     int pcre32_copy_named_substring(const pcre32 *code,
	  PCRE_SPTR32 subject, int *ovector,
	  int stringcount, PCRE_SPTR32 stringname,
	  PCRE_UCHAR32 *buffer, int buffersize);

     int pcre32_copy_substring(PCRE_SPTR32 subject, int *ovector,
	  int stringcount, int stringnumber, PCRE_UCHAR32 *buffer,
	  int buffersize);

     int pcre32_get_named_substring(const pcre32 *code,
	  PCRE_SPTR32 subject, int *ovector,
	  int stringcount, PCRE_SPTR32 stringname,
	  PCRE_SPTR32 *stringptr);

     int pcre32_get_stringnumber(const pcre32 *code,
	  PCRE_SPTR32 name);

     int pcre32_get_stringtable_entries(const pcre32 *code,
	  PCRE_SPTR32 name, PCRE_UCHAR32 **first, PCRE_UCHAR32 **last);

     int pcre32_get_substring(PCRE_SPTR32 subject, int *ovector,
	  int stringcount, int stringnumber,
	  PCRE_SPTR32 *stringptr);

     int pcre32_get_substring_list(PCRE_SPTR32 subject,
	  int *ovector, int stringcount, PCRE_SPTR32 **listptr);

     void pcre32_free_substring(PCRE_SPTR32 stringptr);

     void pcre32_free_substring_list(PCRE_SPTR32 *stringptr);

PCRE 32-BIT API AUXILIARY FUNCTIONS
     pcre32_jit_stack *pcre32_jit_stack_alloc(int startsize, int maxsize);

     void pcre32_jit_stack_free(pcre32_jit_stack *stack);

     void pcre32_assign_jit_stack(pcre32_extra *extra,
	  pcre32_jit_callback callback, void *data);

     const unsigned char *pcre32_maketables(void);

     int pcre32_fullinfo(const pcre32 *code, const pcre32_extra *extra,
	  int what, void *where);

     int pcre32_refcount(pcre32 *code, int adjust);

     int pcre32_config(int what, void *where);

     const char *pcre32_version(void);

     int pcre32_pattern_to_host_byte_order(pcre32 *code,
	  pcre32_extra *extra, const unsigned char *tables);

PCRE 32-BIT API INDIRECTED FUNCTIONS
     void *(*pcre32_malloc)(size_t);

     void (*pcre32_free)(void *);

     void *(*pcre32_stack_malloc)(size_t);

     void (*pcre32_stack_free)(void *);

     int (*pcre32_callout)(pcre32_callout_block *);

PCRE 32-BIT API 32-BIT-ONLY FUNCTION
     int pcre32_utf32_to_host_byte_order(PCRE_UCHAR32 *output,
	  PCRE_SPTR32 input, int length, int *byte_order,
	  int keep_boms);

THE PCRE 32-BIT LIBRARY
     Starting  with  release 8.32, it is possible to compile a PCRE library that
     supports 32-bit character strings, including UTF-32 strings, as well as  or
     instead of the original 8-bit library. This work was done by Christian Per-
     sch,  based  on the work done by Zoltan Herczeg for the 16-bit library. All
     three libraries contain identical sets of functions, used	in  exactly  the
     same  way.  Only the names of the functions and the data types of their ar-
     guments and results are different. To avoid  over-complication  and  reduce
     the  documentation  maintenance  load,  most  of the PCRE documentation de-
     scribes the 8-bit library, with only occasional references  to  the  16-bit
     and  32-bit  libraries.  This page describes what is different when you use
     the 32-bit library.

     WARNING: A single application can be linked with all or any  of  the  three
     libraries, but you must take care when processing any particular pattern to
     use  functions  from  just one library. For example, if you want to study a
     pattern that was compiled	with  pcre32_compile(),  you  must  do	so  with
     pcre32_study(),  not  pcre_study(),  and  you must free the study data with
     pcre32_free_study().

THE HEADER FILE
     There is only one header file, pcre.h. It contains prototypes for	all  the
     functions	in  all  libraries, as well as definitions of flags, structures,
     error codes, etc.

THE LIBRARY NAME
     In Unix-like systems, the 32-bit library is called libpcre32, and can  nor-
     mally  be accesss by adding -lpcre32 to the command for linking an applica-
     tion that uses PCRE.

STRING TYPES
     In the 8-bit library, strings are passed to PCRE library functions as  vec-
     tors  of bytes with the C type "char *". In the 32-bit library, strings are
     passed as vectors of unsigned 32-bit  quantities.	The  macro  PCRE_UCHAR32
     specifies	an  appropriate  data type, and PCRE_SPTR32 is defined as "const
     PCRE_UCHAR32 *". In very many environments, "unsigned int" is a 32-bit data
     type. When PCRE is built, it defines PCRE_UCHAR32 as  "unsigned  int",  but
     checks  that it really is a 32-bit data type. If it is not, the build fails
     with an error message telling the maintainer to modify the  definition  ap-
     propriately.

STRUCTURE TYPES
     The  types  of the opaque structures that are used for compiled 32-bit pat-
     terns and JIT stacks are pcre32 and pcre32_jit_stack respectively. The type
     of the user-accessible structure that  is	returned  by  pcre32_study()  is
     pcre32_extra,  and  the type of the structure that is used for passing data
     to a callout function is pcre32_callout_block. These structures contain the
     same fields, with the same names, as their  8-bit	counterparts.  The  only
     difference  is  that  pointers  to  character strings are 32-bit instead of
     8-bit types.

32-BIT FUNCTIONS
     For every function in the 8-bit library there is a  corresponding	function
     in  the  32-bit  library  with  a	name that starts with pcre32_ instead of
     pcre_. The prototypes are listed above. In addition,  there  is  one  extra
     function,	pcre32_utf32_to_host_byte_order().  This  is  a utility function
     that converts a UTF-32 character string to host byte  order  if  necessary.
     The other 32-bit functions expect the strings they are passed to be in host
     byte order.

     The  input  and  output  arguments of pcre32_utf32_to_host_byte_order() may
     point to the same address, that is, conversion in place is  supported.  The
     output buffer must be at least as long as the input.

     The  length argument specifies the number of 32-bit data units in the input
     string; a negative value specifies a zero-terminated string.

     If byte_order is NULL, it is assumed that the string  starts  off	in  host
     byte  order. This may be changed by byte-order marks (BOMs) anywhere in the
     string (commonly as the first character).

     If byte_order is not NULL, a non-zero value of  the  integer  to  which  it
     points  means  that  the input starts off in host byte order, otherwise the
     opposite order is assumed. Again, BOMs in the string can change  this.  The
     final byte order is passed back at the end of processing.

     If  keep_boms  is	not zero, byte-order mark characters (0xfeff) are copied
     into the output string. Otherwise they are discarded.

     The result of the function is the number of 32-bit units  placed  into  the
     output  buffer, including the zero terminator if the string was zero-termi-
     nated.

SUBJECT STRING OFFSETS
     The lengths and starting offsets of subject strings must  be  specified  in
     32-bit data units, and the offsets within subject strings that are returned
     by the matching functions are in also 32-bit units rather than bytes.

NAMED SUBPATTERNS
     The  name-to-number  translation table that is maintained for named subpat-
     terns uses 32-bit characters. The pcre32_get_stringtable_entries() function
     returns the length of each entry in the table as the number of 32-bit  data
     units.

OPTION NAMES
     There are two new general option names, PCRE_UTF32 and PCRE_NO_UTF32_CHECK,
     which  correspond to PCRE_UTF8 and PCRE_NO_UTF8_CHECK in the 8-bit library.
     In fact, these new options define the same bits in the options word.  There
     is  a  discussion	about  the validity of UTF-32 strings in the pcreunicode
     page.

     For the pcre32_config() function there is an option PCRE_CONFIG_UTF32  that
     returns  1  if UTF-32 support is configured, otherwise 0. If this option is
     given to pcre_config() or pcre16_config(), or if  the  PCRE_CONFIG_UTF8  or
     PCRE_CONFIG_UTF16	option	is  given  to pcre32_config(), the result is the
     PCRE_ERROR_BADOPTION error.

CHARACTER CODES
     In 32-bit mode, when PCRE_UTF32 is not set, character values are treated in
     the same way as in 8-bit, non UTF-8 mode, except, of course, that they  can
     range  from 0 to 0x7fffffff instead of 0 to 0xff. Character types for char-
     acters less than 0xff can therefore be influenced by the locale in the same
     way as before.  Characters greater than 0xff have only  one  case,  and  no
     "type" (such as letter or digit).

     In  UTF-32 mode, the character code is Unicode, in the range 0 to 0x10ffff,
     with the exception of values in the range 0xd800 to  0xdfff  because  those
     are "surrogate" values that are ill-formed in UTF-32.

     A	UTF-32	string	can  indicate  its endianness by special code knows as a
     byte-order mark (BOM). The PCRE functions do  not	handle	this,  expecting
     strings   to   be	 in   host   byte   order.  A  utility	function  called
     pcre32_utf32_to_host_byte_order()	is  provided  to  help	with  this  (see
     above).

ERROR NAMES
     The  error  PCRE_ERROR_BADUTF32  corresponds to its 8-bit counterpart.  The
     error PCRE_ERROR_BADMODE is given when a compiled pattern is  passed  to  a
     function  that processes patterns in the other mode, for example, if a pat-
     tern compiled with pcre_compile() is passed to pcre32_exec().

     There are new error codes whose names begin with PCRE_UTF32_ERR for invalid
     UTF-32 strings, corresponding to the PCRE_UTF8_ERR codes for UTF-8  strings
     that  are described in the section entitled "Reason codes for invalid UTF-8
     strings" in the main pcreapi page. The UTF-32 errors are:

       PCRE_UTF32_ERR1	Surrogate character (range from 0xd800 to 0xdfff)
       PCRE_UTF32_ERR2	Non-character
       PCRE_UTF32_ERR3	Character > 0x10ffff

ERROR TEXTS
     If there is an error while compiling a pattern,  the  error  text	that  is
     passed  back  by  pcre32_compile()  or  pcre32_compile2() is still an 8-bit
     character string, zero-terminated.

CALLOUTS
     The subject and mark fields in the callout block that is passed to a  call-
     out function point to 32-bit vectors.

TESTING
     The  pcretest  program  continues	to  operate  with 8-bit input and output
     files, but it can be used for testing the 32-bit library. If it is run with
     the command line option -32, patterns and	subject  strings  are  converted
     from  8-bit  to  32-bit before being passed to PCRE, and the 32-bit library
     functions are used instead of the 8-bit ones. Returned 32-bit  strings  are
     converted	to  8-bit for output. If both the 8-bit and the 16-bit libraries
     were not compiled, pcretest defaults to 32-bit and the -32  option  is  ig-
     nored.

     When PCRE is being built, the RunTest script that is called by "make check"
     uses  the	pcretest  -C  option  to discover which of the 8-bit, 16-bit and
     32-bit libraries has been built, and runs the tests appropriately.

NOT SUPPORTED IN 32-BIT MODE
     Not all the features of the 8-bit library are available with the 32-bit li-
     brary. The C++ and POSIX wrapper functions support only the 8-bit	library,
     and the pcregrep program is at present 8-bit only.

AUTHOR
     Philip Hazel
     University Computing Service
     Cambridge CB2 3QH, England.

REVISION
     Last updated: 12 May 2013
     Copyright (c) 1997-2013 University of Cambridge.

PCRE 8.33			   12 May 2013				 PCRE(3)

Want to link to this manual page? Use this URL:
<https://man.freebsd.org/cgi/man.cgi?query=pcre32&sektion=3&manpath=FreeBSD+Ports+15.1.quarterly>

home | help