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speech-tools/base_class/string/EST_Regex.cc
2015-09-19 10:52:26 +02:00

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/************************************************************************/
/* */
/* Centre for Speech Technology Research */
/* University of Edinburgh, UK */
/* Copyright (c) 1997 */
/* All Rights Reserved. */
/* */
/* Permission is hereby granted, free of charge, to use and distribute */
/* this software and its documentation without restriction, including */
/* without limitation the rights to use, copy, modify, merge, publish, */
/* distribute, sublicense, and/or sell copies of this work, and to */
/* permit persons to whom this work is furnished to do so, subject to */
/* the following conditions: */
/* 1. The code must retain the above copyright notice, this list of */
/* conditions and the following disclaimer. */
/* 2. Any modifications must be clearly marked as such. */
/* 3. Original authors' names are not deleted. */
/* 4. The authors' names are not used to endorse or promote products */
/* derived from this software without specific prior written */
/* permission. */
/* */
/* THE UNIVERSITY OF EDINBURGH AND THE CONTRIBUTORS TO THIS WORK */
/* DISCLAIM ALL WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING */
/* ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO EVENT */
/* SHALL THE UNIVERSITY OF EDINBURGH NOR THE CONTRIBUTORS BE LIABLE */
/* FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES */
/* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN */
/* AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, */
/* ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF */
/* THIS SOFTWARE. */
/* */
/************************************************************************/
/* Author : Richard Caley (rjc@cstr.ed.ac.uk) */
/* Date : February 1997 */
/* -------------------------------------------------------------------- */
/* */
/* A Regular expression class to go with the CSTR EST_String class. Uses*/
/* Henry Spencer`s regexp routines which allocate space dynamically */
/* using malloc, so we use free in here rather than wfree because */
/* wfree might at some time start doing something more than just be a */
/* safe wrapper around free. If you try and use another regexp */
/* package, beware of changes to how memory is allocated. */
/* */
/* We maintain two compiled versions, one for substring matches and */
/* one for whole string matches (because sometimes the regexp */
/* compiler can special case the latter). These are compiled when */
/* first used. */
/* */
/************************************************************************/
#ifdef NO_EST
# include <unistd.h>
#else
# include "EST_unix.h"
#endif
#include <cstdlib>
#include <cstdio>
#include <cstring>
#include "EST_String.h"
#include "EST_Regex.h"
#ifdef sun
#ifndef __svr4__
/* SunOS */
#include <cstring>
#endif
#endif
// extern "C" {
#include "regexp.h"
/*
void *t_regcomp(void *v)
{
return v;
}
void *cpp_regcomp(void *v)
{
return v;
}
*/
// #define wfree(P) (1==1)
// These define the different escape conventions for the FSF's
// regexp code and Henry Spencer's
static const char *fsf_magic="^$*+?[].\\";
static const char *fsf_magic_backslashed="()|<>";
static const char *spencer_magic="^$*+?[].()|\\\n";
static const char *spencer_magic_backslashed="<>";
EST_Regex RXwhite("[ \n\t\r]+");
EST_Regex RXalpha("[A-Za-z]+");
EST_Regex RXlowercase("[a-z]+");
EST_Regex RXuppercase("[A-Z]+");
EST_Regex RXalphanum("[0-9A-Za-z]+");
EST_Regex RXidentifier("[A-Za-z_][0-9A-Za-z_]+");
EST_Regex RXint("-?[0-9]+");
EST_Regex RXdouble("-?\\(\\([0-9]+\\.[0-9]*\\)\\|\\([0-9]+\\)\\|\\(\\.[0-9]+\\)\\)\\([eE][---+]?[0-9]+\\)?");
// use this to free compiled regex since the regexp package uses malloc
// and walloc might end up doing something clever.
/* extern "C" void free(void *p); */
#if NSUBEXP != EST_Regex_max_subexpressions
# error "EST_Regex_max_subexpressions must be equal to NSUBEXP"
#endif
EST_Regex::EST_Regex(void) : EST_String()
{
compiled = NULL;
compiled_match = NULL;
}
EST_Regex::EST_Regex(const char *s) : EST_String(s)
{
compiled = NULL;
compiled_match = NULL;
}
EST_Regex::EST_Regex(EST_String s) : EST_String(s)
{
compiled = NULL;
compiled_match = NULL;
}
EST_Regex::EST_Regex(const EST_Regex &ex) : EST_String(ex)
{
compiled = NULL;
compiled_match = NULL;
}
EST_Regex::~EST_Regex()
{
if (compiled_match)
free(compiled_match);
if (compiled)
free(compiled);
}
// Convert a regular expression from the external syntax (defined by the
// the FSF library) to the one expected by the regexp routines (which
// say it's V8 syntax).
char *EST_Regex::regularize(int match) const
{
char *reg = walloc(char, size()*2+3);
char *r=reg;
const char *e;
int magic=0,last_was_bs=0;
const char * in_brackets=NULL;
const char *ex = (size()==0)?"":str();
if (match && *ex != '^')
*(r++) = '^';
for(e=ex; *e ; e++)
{
if (*e == '\\' && !last_was_bs)
{
last_was_bs=1;
continue;
}
magic=strchr((last_was_bs?fsf_magic_backslashed:fsf_magic), *e)!=NULL;
if (in_brackets)
{
*(r++) = *e;
if (*e == ']' && (e-in_brackets)>1)
in_brackets=0;
}
else if (magic)
{
if (strchr(spencer_magic_backslashed, *e))
*(r++) = '\\';
*(r++) = *e;
if (*e == '[')
in_brackets=e;
}
else
{
if (strchr(spencer_magic, *e))
*(r++) = '\\';
*(r++) = *e;
}
last_was_bs=0;
}
if (match && (e==ex || *(e-1) != '$'))
{
if (last_was_bs)
*(r++) = '\\';
*(r++) = '$';
}
*r='\0';
// cerr<<"reg||"<<ex<<"||"<<reg<<"\n";
return reg;
}
void EST_Regex::compile()
{
if (!compiled)
{
char *reg=regularize(0);
void * t =(void *)hs_regcomp(reg);
compiled=t;
wfree(reg);
}
if (!compiled)
cerr << "EST_Regex: can't compile '" << str() << "'\n";
}
void EST_Regex::compile_match()
{
if (!compiled_match)
{
char *reg=regularize(1);
void * t =(void *)hs_regcomp(reg);
compiled_match=t;
wfree(reg);
}
if (!compiled_match)
cerr << "EST_Regex: can't compile '" << str() << "'\n";
}
int EST_Regex::run(const char *on, int from, int &start, int &end, int *starts, int *ends)
{
compile();
if (compiled && from <= (int)strlen(on))
{
if (hs_regexec((hs_regexp *)compiled, on+from))
{
hs_regexp *re = (hs_regexp *)compiled;
start = re->startp[0] - on;
end = re->endp[0]- on;
if (starts)
{
int i;
for (i=0; i<EST_Regex_max_subexpressions; i++)
starts[i] = re->startp[i]?(re->startp[i] - on):-1;
}
if (ends)
{
int i;
for (i=0; i<EST_Regex_max_subexpressions; i++)
ends[i] = re->endp[i]?(re->endp[i] - on):-1;
}
return 1;
}
}
return 0;
}
int EST_Regex::run_match(const char *on, int from, int *starts, int *ends)
{
compile_match();
hs_regexp *re = (hs_regexp *)compiled_match;
if (compiled_match && from <= (int)strlen(on))
if (hs_regexec(re, on+from))
{
if (starts)
{
int i;
for (i=0; i<EST_Regex_max_subexpressions; i++)
starts[i] = re->startp[i]?(re->startp[i] - on):-1;
}
if (ends)
{
int i;
for (i=0; i<EST_Regex_max_subexpressions; i++)
ends[i] = re->endp[i]?(re->endp[i] - on):-1;
}
return 1;
}
return 0;
}
EST_Regex &EST_Regex::operator = (const EST_Regex ex)
{
((EST_String &)(*this)) = (EST_String)ex;
compiled = NULL;
compiled_match = NULL;
return *this;
}
EST_Regex &EST_Regex::operator = (const EST_String s)
{
((EST_String &)(*this)) = s;
compiled = NULL;
compiled_match = NULL;
return *this;
}
EST_Regex &EST_Regex::operator = (const char *s)
{
((EST_String &)(*this)) = s;
compiled = NULL;
compiled_match = NULL;
return *this;
}
ostream &operator << (ostream &s, const EST_Regex &str)
{
return s << (EST_String)str;
}