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diff --git a/doc/pcre16.3 b/doc/pcre16.3 new file mode 100644 index 0000000..85126a6 --- /dev/null +++ b/doc/pcre16.3 @@ -0,0 +1,371 @@ +.TH PCRE 3 "12 May 2013" "PCRE 8.33" +.SH NAME +PCRE - Perl-compatible regular expressions +.sp +.B #include <pcre.h> +. +. +.SH "PCRE 16-BIT API BASIC FUNCTIONS" +.rs +.sp +.nf +.B pcre16 *pcre16_compile(PCRE_SPTR16 \fIpattern\fP, int \fIoptions\fP, +.B " const char **\fIerrptr\fP, int *\fIerroffset\fP," +.B " const unsigned char *\fItableptr\fP);" +.sp +.B pcre16 *pcre16_compile2(PCRE_SPTR16 \fIpattern\fP, int \fIoptions\fP, +.B " int *\fIerrorcodeptr\fP," +.B " const char **\fIerrptr\fP, int *\fIerroffset\fP," +.B " const unsigned char *\fItableptr\fP);" +.sp +.B pcre16_extra *pcre16_study(const pcre16 *\fIcode\fP, int \fIoptions\fP, +.B " const char **\fIerrptr\fP);" +.sp +.B void pcre16_free_study(pcre16_extra *\fIextra\fP); +.sp +.B int pcre16_exec(const pcre16 *\fIcode\fP, "const pcre16_extra *\fIextra\fP," +.B " PCRE_SPTR16 \fIsubject\fP, int \fIlength\fP, int \fIstartoffset\fP," +.B " int \fIoptions\fP, int *\fIovector\fP, int \fIovecsize\fP);" +.sp +.B int pcre16_dfa_exec(const pcre16 *\fIcode\fP, "const pcre16_extra *\fIextra\fP," +.B " PCRE_SPTR16 \fIsubject\fP, int \fIlength\fP, int \fIstartoffset\fP," +.B " int \fIoptions\fP, int *\fIovector\fP, int \fIovecsize\fP," +.B " int *\fIworkspace\fP, int \fIwscount\fP);" +.fi +. +. +.SH "PCRE 16-BIT API STRING EXTRACTION FUNCTIONS" +.rs +.sp +.nf +.B int pcre16_copy_named_substring(const pcre16 *\fIcode\fP, +.B " PCRE_SPTR16 \fIsubject\fP, int *\fIovector\fP," +.B " int \fIstringcount\fP, PCRE_SPTR16 \fIstringname\fP," +.B " PCRE_UCHAR16 *\fIbuffer\fP, int \fIbuffersize\fP);" +.sp +.B int pcre16_copy_substring(PCRE_SPTR16 \fIsubject\fP, int *\fIovector\fP, +.B " int \fIstringcount\fP, int \fIstringnumber\fP, PCRE_UCHAR16 *\fIbuffer\fP," +.B " int \fIbuffersize\fP);" +.sp +.B int pcre16_get_named_substring(const pcre16 *\fIcode\fP, +.B " PCRE_SPTR16 \fIsubject\fP, int *\fIovector\fP," +.B " int \fIstringcount\fP, PCRE_SPTR16 \fIstringname\fP," +.B " PCRE_SPTR16 *\fIstringptr\fP);" +.sp +.B int pcre16_get_stringnumber(const pcre16 *\fIcode\fP, +.B " PCRE_SPTR16 \fIname\fP); +.sp +.B int pcre16_get_stringtable_entries(const pcre16 *\fIcode\fP, +.B " PCRE_SPTR16 \fIname\fP, PCRE_UCHAR16 **\fIfirst\fP, PCRE_UCHAR16 **\fIlast\fP);" +.sp +.B int pcre16_get_substring(PCRE_SPTR16 \fIsubject\fP, int *\fIovector\fP, +.B " int \fIstringcount\fP, int \fIstringnumber\fP," +.B " PCRE_SPTR16 *\fIstringptr\fP);" +.sp +.B int pcre16_get_substring_list(PCRE_SPTR16 \fIsubject\fP, +.B " int *\fIovector\fP, int \fIstringcount\fP, PCRE_SPTR16 **\fIlistptr\fP);" +.sp +.B void pcre16_free_substring(PCRE_SPTR16 \fIstringptr\fP); +.sp +.B void pcre16_free_substring_list(PCRE_SPTR16 *\fIstringptr\fP); +.fi +. +. +.SH "PCRE 16-BIT API AUXILIARY FUNCTIONS" +.rs +.sp +.nf +.B pcre16_jit_stack *pcre16_jit_stack_alloc(int \fIstartsize\fP, int \fImaxsize\fP); +.sp +.B void pcre16_jit_stack_free(pcre16_jit_stack *\fIstack\fP); +.sp +.B void pcre16_assign_jit_stack(pcre16_extra *\fIextra\fP, +.B " pcre16_jit_callback \fIcallback\fP, void *\fIdata\fP);" +.sp +.B const unsigned char *pcre16_maketables(void); +.sp +.B int pcre16_fullinfo(const pcre16 *\fIcode\fP, "const pcre16_extra *\fIextra\fP," +.B " int \fIwhat\fP, void *\fIwhere\fP);" +.sp +.B int pcre16_refcount(pcre16 *\fIcode\fP, int \fIadjust\fP); +.sp +.B int pcre16_config(int \fIwhat\fP, void *\fIwhere\fP); +.sp +.B const char *pcre16_version(void); +.sp +.B int pcre16_pattern_to_host_byte_order(pcre16 *\fIcode\fP, +.B " pcre16_extra *\fIextra\fP, const unsigned char *\fItables\fP);" +.fi +. +. +.SH "PCRE 16-BIT API INDIRECTED FUNCTIONS" +.rs +.sp +.nf +.B void *(*pcre16_malloc)(size_t); +.sp +.B void (*pcre16_free)(void *); +.sp +.B void *(*pcre16_stack_malloc)(size_t); +.sp +.B void (*pcre16_stack_free)(void *); +.sp +.B int (*pcre16_callout)(pcre16_callout_block *); +.fi +. +. +.SH "PCRE 16-BIT API 16-BIT-ONLY FUNCTION" +.rs +.sp +.nf +.B int pcre16_utf16_to_host_byte_order(PCRE_UCHAR16 *\fIoutput\fP, +.B " PCRE_SPTR16 \fIinput\fP, int \fIlength\fP, int *\fIbyte_order\fP," +.B " int \fIkeep_boms\fP);" +.fi +. +. +.SH "THE PCRE 16-BIT LIBRARY" +.rs +.sp +Starting with release 8.30, it is possible to compile a PCRE library that +supports 16-bit character strings, including UTF-16 strings, as well as or +instead of the original 8-bit library. The majority of the work to make this +possible was done by Zoltan Herczeg. The two libraries contain identical sets +of functions, used in exactly the same way. Only the names of the functions and +the data types of their arguments and results are different. To avoid +over-complication and reduce the documentation maintenance load, most of the +PCRE documentation describes the 8-bit library, with only occasional references +to the 16-bit library. This page describes what is different when you use the +16-bit library. +.P +WARNING: A single application can be linked with both 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 +\fBpcre16_compile()\fP, you must do so with \fBpcre16_study()\fP, not +\fBpcre_study()\fP, and you must free the study data with +\fBpcre16_free_study()\fP. +. +. +.SH "THE HEADER FILE" +.rs +.sp +There is only one header file, \fBpcre.h\fP. It contains prototypes for all the +functions in all libraries, as well as definitions of flags, structures, error +codes, etc. +. +. +.SH "THE LIBRARY NAME" +.rs +.sp +In Unix-like systems, the 16-bit library is called \fBlibpcre16\fP, and can +normally be accesss by adding \fB-lpcre16\fP to the command for linking an +application that uses PCRE. +. +. +.SH "STRING TYPES" +.rs +.sp +In the 8-bit library, strings are passed to PCRE library functions as vectors +of bytes with the C type "char *". In the 16-bit library, strings are passed as +vectors of unsigned 16-bit quantities. The macro PCRE_UCHAR16 specifies an +appropriate data type, and PCRE_SPTR16 is defined as "const PCRE_UCHAR16 *". In +very many environments, "short int" is a 16-bit data type. When PCRE is built, +it defines PCRE_UCHAR16 as "unsigned short int", but checks that it really is a +16-bit data type. If it is not, the build fails with an error message telling +the maintainer to modify the definition appropriately. +. +. +.SH "STRUCTURE TYPES" +.rs +.sp +The types of the opaque structures that are used for compiled 16-bit patterns +and JIT stacks are \fBpcre16\fP and \fBpcre16_jit_stack\fP respectively. The +type of the user-accessible structure that is returned by \fBpcre16_study()\fP +is \fBpcre16_extra\fP, and the type of the structure that is used for passing +data to a callout function is \fBpcre16_callout_block\fP. 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 16-bit instead of +8-bit types. +. +. +.SH "16-BIT FUNCTIONS" +.rs +.sp +For every function in the 8-bit library there is a corresponding function in +the 16-bit library with a name that starts with \fBpcre16_\fP instead of +\fBpcre_\fP. The prototypes are listed above. In addition, there is one extra +function, \fBpcre16_utf16_to_host_byte_order()\fP. This is a utility function +that converts a UTF-16 character string to host byte order if necessary. The +other 16-bit functions expect the strings they are passed to be in host byte +order. +.P +The \fIinput\fP and \fIoutput\fP arguments of +\fBpcre16_utf16_to_host_byte_order()\fP 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. +.P +The \fIlength\fP argument specifies the number of 16-bit data units in the +input string; a negative value specifies a zero-terminated string. +.P +If \fIbyte_order\fP 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). +.P +If \fIbyte_order\fP 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. +.P +If \fIkeep_boms\fP is not zero, byte-order mark characters (0xfeff) are copied +into the output string. Otherwise they are discarded. +.P +The result of the function is the number of 16-bit units placed into the output +buffer, including the zero terminator if the string was zero-terminated. +. +. +.SH "SUBJECT STRING OFFSETS" +.rs +.sp +The lengths and starting offsets of subject strings must be specified in 16-bit +data units, and the offsets within subject strings that are returned by the +matching functions are in also 16-bit units rather than bytes. +. +. +.SH "NAMED SUBPATTERNS" +.rs +.sp +The name-to-number translation table that is maintained for named subpatterns +uses 16-bit characters. The \fBpcre16_get_stringtable_entries()\fP function +returns the length of each entry in the table as the number of 16-bit data +units. +. +. +.SH "OPTION NAMES" +.rs +.sp +There are two new general option names, PCRE_UTF16 and PCRE_NO_UTF16_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 +.\" HTML <a href="pcreunicode.html#utf16strings"> +.\" </a> +validity of UTF-16 strings +.\" +in the +.\" HREF +\fBpcreunicode\fP +.\" +page. +.P +For the \fBpcre16_config()\fP function there is an option PCRE_CONFIG_UTF16 +that returns 1 if UTF-16 support is configured, otherwise 0. If this option is +given to \fBpcre_config()\fP or \fBpcre32_config()\fP, or if the +PCRE_CONFIG_UTF8 or PCRE_CONFIG_UTF32 option is given to \fBpcre16_config()\fP, +the result is the PCRE_ERROR_BADOPTION error. +. +. +.SH "CHARACTER CODES" +.rs +.sp +In 16-bit mode, when PCRE_UTF16 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 0xffff instead of 0 to 0xff. Character types for characters 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). +.P +In UTF-16 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 used in pairs to encode values greater than 0xffff. +.P +A UTF-16 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 +\fBpcre16_utf16_to_host_byte_order()\fP is provided to help with this (see +above). +. +. +.SH "ERROR NAMES" +.rs +.sp +The errors PCRE_ERROR_BADUTF16_OFFSET and PCRE_ERROR_SHORTUTF16 correspond to +their 8-bit counterparts. 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 pattern compiled with \fBpcre_compile()\fP is passed to +\fBpcre16_exec()\fP. +.P +There are new error codes whose names begin with PCRE_UTF16_ERR for invalid +UTF-16 strings, corresponding to the PCRE_UTF8_ERR codes for UTF-8 strings that +are described in the section entitled +.\" HTML <a href="pcreapi.html#badutf8reasons"> +.\" </a> +"Reason codes for invalid UTF-8 strings" +.\" +in the main +.\" HREF +\fBpcreapi\fP +.\" +page. The UTF-16 errors are: +.sp + PCRE_UTF16_ERR1 Missing low surrogate at end of string + PCRE_UTF16_ERR2 Invalid low surrogate follows high surrogate + PCRE_UTF16_ERR3 Isolated low surrogate + PCRE_UTF16_ERR4 Non-character +. +. +.SH "ERROR TEXTS" +.rs +.sp +If there is an error while compiling a pattern, the error text that is passed +back by \fBpcre16_compile()\fP or \fBpcre16_compile2()\fP is still an 8-bit +character string, zero-terminated. +. +. +.SH "CALLOUTS" +.rs +.sp +The \fIsubject\fP and \fImark\fP fields in the callout block that is passed to +a callout function point to 16-bit vectors. +. +. +.SH "TESTING" +.rs +.sp +The \fBpcretest\fP program continues to operate with 8-bit input and output +files, but it can be used for testing the 16-bit library. If it is run with the +command line option \fB-16\fP, patterns and subject strings are converted from +8-bit to 16-bit before being passed to PCRE, and the 16-bit library functions +are used instead of the 8-bit ones. Returned 16-bit strings are converted to +8-bit for output. If both the 8-bit and the 32-bit libraries were not compiled, +\fBpcretest\fP defaults to 16-bit and the \fB-16\fP option is ignored. +.P +When PCRE is being built, the \fBRunTest\fP script that is called by "make +check" uses the \fBpcretest\fP \fB-C\fP option to discover which of the 8-bit, +16-bit and 32-bit libraries has been built, and runs the tests appropriately. +. +. +.SH "NOT SUPPORTED IN 16-BIT MODE" +.rs +.sp +Not all the features of the 8-bit library are available with the 16-bit +library. The C++ and POSIX wrapper functions support only the 8-bit library, +and the \fBpcregrep\fP program is at present 8-bit only. +. +. +.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 |