PCRE – Perl-compatible regular expressions Size And Other Limitations There are some size limitations in PCRE but it is hoped that they will never in practice be relevant. The maximum length of a compiled pattern is approximately 64K data units (bytes for the 8-bit library, 16-bit units for the 16-bit library, and 32-bit units for…
PCRE – Perl-compatible regular expressions Pcre Just-In-Time Compiler Support Just-in-time compiling is a heavyweight optimization that can greatly speed up pattern matching. However, it comes at the cost of extra processing before the match is performed. Therefore, it is of most benefit when the same pattern is going to be matched many times. This does…
PCRE – Perl-compatible regular expressions. Synopsis Of C++ Wrapper #include <pcrecpp.h> Description The C++ wrapper for PCRE was provided by Google Inc. Some additional functionality was added by Giuseppe Maxia. This brief man page was constructed from the notes in the pcrecpp.h file, which should be consulted for further details. Note that the C++ wrapper…
PCRE – Perl-compatible regular expressions Differences Between Pcre And Perl This document describes the differences in the ways that PCRE and Perl handle regular expressions. The differences described here are with respect to Perl versions 5.10 and above. 1. PCRE has only a subset of Perl’s Unicode support. Details of what it does have are…
PCRE – Perl-compatible regular expressions Synopsis #include <pcre.h> int (*pcre_callout)(pcre_callout_block *); int (*pcre16_callout)(pcre16_callout_block *); int (*pcre32_callout)(pcre32_callout_block *); Description PCRE provides a feature called "callout", which is a means of temporarily passing control to the caller of PCRE in the middle of pattern matching. The caller of PCRE provides an external function by putting its entry…
PCRE – Perl-compatible regular expressions Building Pcre PCRE is distributed with a configure 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 CMake instead of configure. The text file README contains general information about building with…
PCRE – Perl-compatible regular expressions #include < pcre.h> Pcre Native Api Basic Functions pcre *pcre_compile(const char *pattern, int options, const char **errptr, int *erroffset, const unsigned char *tableptr); pcre *pcre_compile2(const char *pattern, int options, int *errorcodeptr, const char **errptr, int *erroffset, const unsigned char *tableptr); pcre_extra *pcre_study(const pcre *code, int options, const char **errptr); void…
PCRE – Perl-compatible regular expressions Synopsis #include <pcre.h> const char *pcre_version(void); const char *pcre16_version(void); const char *pcre32_version(void); Description This function (even in the 16-bit and 32-bit libraries) returns a zero-terminated, 8-bit character string that gives the version number of the PCRE library and the date of its release. There is a complete description of the…
PCRE – Perl-compatible regular expressions Synopsis #include <pcre.h> int pcre32_utf32_to_host_byte_order(PCRE_UCHAR32 *output, PCRE_SPTR32 input, int length, int *host_byte_order, int keep_boms); Description This function, which exists only in the 32-bit library, converts a UTF-32 string to the correct order for the current host, taking account of any byte order marks (BOMs) within the string. Its arguments are:…
PCRE – Perl-compatible regular expressions Synopsis #include <pcre.h> int pcre16_utf16_to_host_byte_order(PCRE_UCHAR16 *output, PCRE_SPTR16 input, int length, int *host_byte_order, int keep_boms); Description This function, which exists only in the 16-bit library, converts a UTF-16 string to the correct order for the current host, taking account of any byte order marks (BOMs) within the string. Its arguments are:…
PCRE – Perl-compatible regular expressions Synopsis #include <pcre.h> pcre_extra *pcre_study(const pcre *code, int options, const char **errptr); pcre16_extra *pcre16_study(const pcre16 *code, int options, const char **errptr); pcre32_extra *pcre32_study(const pcre32 *code, int options, const char **errptr); Description This function studies a compiled pattern, to see if additional information can be extracted that might speed up matching….
PCRE – Perl-compatible regular expressions Synopsis #include <pcre.h> int pcre_refcount(pcre *code, int adjust); int pcre16_refcount(pcre16 *code, int adjust); int pcre32_refcount(pcre32 *code, int adjust); Description This function is used to maintain a reference count inside a data block that contains a compiled pattern. Its arguments are: code Compiled regular expression adjust Adjustment to reference value The yield of…
PCRE – Perl-compatible regular expressions Synopsis #include <pcre.h> int pcre_pattern_to_host_byte_order(pcre *code, pcre_extra *extra, const unsigned char *tables); int pcre16_pattern_to_host_byte_order(pcre16 *code, pcre16_extra *extra, const unsigned char *tables); int pcre32_pattern_to_host_byte_order(pcre32 *code, pcre32_extra *extra, const unsigned char *tables); Description This function ensures that the bytes in 2-byte and 4-byte values in a compiled pattern are in the correct…
PCRE – Perl-compatible regular expressions Synopsis #include <pcre.h> const unsigned char *pcre_maketables(void); const unsigned char *pcre16_maketables(void); const unsigned char *pcre32_maketables(void); Description This function builds a set of character tables for character values less than 256. These can be passed to pcre[16|32]_compile() to override PCRE’s internal, built-in tables (which were made by pcre[16|32]_maketables() when PCRE was…
PCRE – Perl-compatible regular expressions Synopsis #include <pcre.h> void pcre_jit_stack_free(pcre_jit_stack *stack); void pcre16_jit_stack_free(pcre16_jit_stack *stack); void pcre32_jit_stack_free(pcre32_jit_stack *stack); Description This function is used to free a JIT stack that was created by pcre[16|32]_jit_stack_alloc() when it is no longer needed. For more details, see the pcrejit page. There is a complete description of the PCRE native API…
PCRE – Perl-compatible regular expressions Synopsis #include <pcre.h> pcre_jit_stack *pcre_jit_stack_alloc(int startsize, int maxsize); pcre16_jit_stack *pcre16_jit_stack_alloc(int startsize, int maxsize); pcre32_jit_stack *pcre32_jit_stack_alloc(int startsize, int maxsize); Description This function is used to create a stack for use by the code compiled by the JIT optimization of pcre[16|32]_study(). The arguments are a starting size for the stack, and a…
PCRE – Perl-compatible regular expressions Synopsis #include <pcre.h> int pcre_jit_exec(const pcre *code, const pcre_extra *extra, const char *subject, int length, int startoffset, int options, int *ovector, int ovecsize, pcre_jit_stack *jstack); int pcre16_jit_exec(const pcre16 *code, const pcre16_extra *extra, PCRE_SPTR16 subject, int length, int startoffset, int options, int *ovector, int ovecsize, pcre_jit_stack *jstack); int pcre32_jit_exec(const pcre32 *code,…
PCRE – Perl-compatible regular expressions Synopsis #include <pcre.h> int pcre_get_substring_list(const char *subject, int *ovector, int stringcount, const char ***listptr); int pcre16_get_substring_list(PCRE_SPTR16 subject, int *ovector, int stringcount, PCRE_SPTR16 **listptr); int pcre32_get_substring_list(PCRE_SPTR32 subject, int *ovector, int stringcount, PCRE_SPTR32 **listptr); Description This is a convenience function for extracting a list of all the captured substrings. The arguments are:…
PCRE – Perl-compatible regular expressions Synopsis #include <pcre.h> int pcre_get_substring(const char *subject, int *ovector, int stringcount, int stringnumber, const char **stringptr); int pcre16_get_substring(PCRE_SPTR16 subject, int *ovector, int stringcount, int stringnumber, PCRE_SPTR16 *stringptr); int pcre32_get_substring(PCRE_SPTR32 subject, int *ovector, int stringcount, int stringnumber, PCRE_SPTR32 *stringptr); Description This is a convenience function for extracting a captured substring. The…
PCRE – Perl-compatible regular expressions Synopsis #include <pcre.h> int pcre_get_stringtable_entries(const pcre *code, const char *name, char **first, char **last); int pcre16_get_stringtable_entries(const pcre16 *code, PCRE_SPTR16 name, PCRE_UCHAR16 **first, PCRE_UCHAR16 **last); int pcre32_get_stringtable_entries(const pcre32 *code, PCRE_SPTR32 name, PCRE_UCHAR32 **first, PCRE_UCHAR32 **last); Description This convenience function finds, for a compiled pattern, the first and last entries for a…