#ifndef lint
static char rcsid[] = "@(#$Id: textsplit.cpp,v 1.20 2006-02-01 14:18:20 dockes Exp $ (C) 2004 J.F.Dockes";
#endif
/*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the
* Free Software Foundation, Inc.,
* 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*/
#ifndef TEST_TEXTSPLIT
#include <iostream>
#include <string>
#include <set>
#include "textsplit.h"
#include "debuglog.h"
#include "utf8iter.h"
#include "uproplist.h"
#ifndef NO_NAMESPACES
using namespace std;
#endif /* NO_NAMESPACES */
/**
* Splitting a text into words. The code in this file will work with any
* charset where the basic separators (.,- etc.) have their ascii values
* (ok for UTF-8, ascii, iso8859* and quite a few others).
*
* We work in a way which would make it quite difficult to handle non-ascii
* separator chars (en-dash, etc.). We would then need to actually parse the
* utf-8 stream, and use a different way to classify the characters (instead
* of a 256 slot array).
*
* We are also not using capitalization information.
*
* How to fix: use some kind of utf-8 aware iterator, or convert to UCS4 first.
* Then specialcase all 'real' utf chars, by checking for the few
* punctuation ones we're interested in (put them in a map). Then
* classify all other non-ascii as letter, and use the current method
* for chars < 127.
*/
// Character classes: we have three main groups, and then some chars
// are their own class because they want special handling.
// We have an array with 256 slots where we keep the character types.
// The array could be fully static, but we use a small function to fill it
// once.
enum CharClass {LETTER=256, SPACE=257, DIGIT=258};
static int charclasses[256];
static set<unsigned int> unicign;
static void setcharclasses()
{
static int init = 0;
if (init)
return;
unsigned int i;
for (i = 0 ; i < 256 ; i ++)
charclasses[i] = LETTER;
for (i = 0; i < ' ';i++)
charclasses[i] = SPACE;
char digits[] = "0123456789";
for (i = 0; i < strlen(digits); i++)
charclasses[int(digits[i])] = DIGIT;
char blankspace[] = "\t\v\f ";
for (i = 0; i < strlen(blankspace); i++)
charclasses[int(blankspace[i])] = SPACE;
char seps[] = "!\"$%&()/<=>[\\]^{|}~:;*`?";
for (i = 0; i < strlen(seps); i++)
charclasses[int(seps[i])] = SPACE;
char special[] = ".@+-,#'\n\r";
for (i = 0; i < strlen(special); i++)
charclasses[int(special[i])] = special[i];
init = 1;
//for (i=0;i<256;i++)cerr<<i<<" -> "<<charclasses[i]<<endl;
for (i = 0; i < sizeof(uniign); i++)
unicign.insert(uniign[i]);
unicign.insert((unsigned int)-1);
}
// Do some checking (the kind which is simpler to do here than in the
// main loop), then send term to our client.
inline bool TextSplit::emitterm(bool isspan, string &w, int pos,
int btstart, int btend)
{
LOGDEB2(("TextSplit::emitterm: '%s' pos %d\n", w.c_str(), pos));
unsigned int l = w.length();
if (l > 0 && l < (unsigned)maxWordLength) {
if (l == 1) {
// 1 char word: we index single letters and digits, but
// nothing else
int c = (int)w[0];
if (charclasses[c] != LETTER && charclasses[c] != DIGIT) {
//cerr << "ERASING single letter term " << c << endl;
return true;
}
}
if (pos != prevpos || l != prevterm.length() || w != prevterm) {
bool ret = cb->takeword(w, pos, btstart, btend);
prevterm = w;
prevpos = pos;
return ret;
}
}
return true;
}
/**
* A routine called from different places in text_to_words(), to
* adjust the current state of the parser, and call the word
* handler/emitter. Emit and reset the current word, possibly emit the current
* span (if different). In query mode, words are not emitted, only final spans
*
* This is purely for factoring common code from different places
* text_to_words().
*
* @return true if ok, false for error. Splitting should stop in this case.
* @param word Word value. This will be empty on return in ALL non-error
* cases
* @param wordpos Term position for word. Always ++ by us.
* @param span Span value
* @param spanpos Term position for the current span
* @param spanerase Set if the current span is at its end. Reset it.
* @param bp The current BYTE position in the stream
*/
inline bool TextSplit::doemit(bool spanerase, int bp)
{
#if 0
cerr << "doemit: " << "w: '" << word << "' wp: "<< wordpos << " s: '" <<
span << "' sp: " << spanpos << " spe: " << spanerase << " bp: " << bp
<< endl;
#endif
// Emit span. When splitting for query, we only emit final spans
if (spanerase) {
// Maybe trim at end These are chars that we would keep inside
// a span, but not at the end
while (span.length() > 0) {
switch (span[span.length()-1]) {
case '.':
case ',':
case '@':
case '\'':
span.resize(span.length()-1);
if (--bp < 0)
bp=0;
break;
default:
goto breakloop1;
}
}
breakloop1:
if (!emitterm(true, span, spanpos, bp-span.length(), bp))
return false;
}
// Emit word if different from span and not query mode
if (!fq && (!spanerase || (word.length() != span.length())))
if (!emitterm(false, word, wordpos, bp-word.length(), bp))
return false;
// Adjust state
wordpos++;
word.erase();
if (spanerase) {
span.erase();
spanpos = wordpos;
}
return true;
}
static inline int whatcc(unsigned int c)
{
if (c <= 127) {
return charclasses[c];
} else {
if (unicign.find(c) != unicign.end())
return SPACE;
else
return LETTER;
}
}
/**
* Splitting a text into terms to be indexed.
* We basically emit a word every time we see a separator, but some chars are
* handled specially so that special cases, ie, c++ and dockes@okyz.com etc,
* are handled properly,
*/
bool TextSplit::text_to_words(const string &in)
{
LOGDEB2(("TextSplit::text_to_words: cb %p\n", cb));
setcharclasses();
span.erase();
word.erase(); // Current word: no punctuation at all in there
number = false;
wordpos = spanpos = charpos = 0;
Utf8Iter it(in);
for (; !it.eof(); it++, charpos++) {
unsigned int c = *it;
if (c == (unsigned int)-1) {
LOGERR(("Textsplit: error occured while scanning UTF-8 string\n"));
return false;
}
int cc = whatcc(c);
switch (cc) {
case SPACE:
SPACE:
if (word.length() || span.length()) {
if (!doemit(true, it.getBpos()))
return false;
number = false;
}
break;
case '-':
case '+':
if (word.length() == 0) {
if (whatcc(it[charpos+1]) == DIGIT) {
number = true;
word += it;
span += it;
} else
span += it;
} else {
if (!doemit(false, it.getBpos()))
return false;
number = false;
span += it;
}
break;
case '.':
case ',':
if (number) {
word += it;
span += it;
break;
} else {
// If . inside a word, keep it, else, this is whitespace.
// We also keep an initial '.' for catching .net, but this adds
// quite a few spurious terms !
// Another problem is that something like .x-errs
// will be split as .x-errs, x, errs but not x-errs
// A final comma in a word will be removed by doemit
if (cc == '.') {
if (word.length()) {
if (!doemit(false, it.getBpos()))
return false;
// span length could have been adjusted by trimming
// inside doemit
if (span.length())
span += it;
break;
} else {
span += it;
break;
}
}
}
goto SPACE;
break;
case '@':
if (word.length()) {
if (!doemit(false, it.getBpos()))
return false;
number = false;
}
span += it;
break;
case '\'':
// If in word, potential span: o'brien, else, this is more
// whitespace
if (word.length()) {
if (!doemit(false, it.getBpos()))
return false;
number = false;
span += it;
}
break;
case '#':
// Keep it only at end of word... Special case for c# you see...
if (word.length() > 0) {
int w = whatcc(it[charpos+1]);
if (w == SPACE || w == '\n' || w == '\r') {
word += it;
span += it;
break;
}
}
goto SPACE;
break;
case '\n':
case '\r':
if (span.length() && span[span.length() - 1] == '-') {
// if '-' is the last char before end of line, just
// ignore the line change. This is the right thing to
// do almost always. We'd then need a way to check if
// the - was added as part of the word hyphenation, or was
// there in the first place, but this would need a dictionary.
// Also we'd need to check for a soft-hyphen and remove it,
// but this would require more utf-8 magic
} else {
// Handle like a normal separator
goto SPACE;
}
break;
case DIGIT:
if (word.length() == 0)
number = true;
/* FALLTHROUGH */
case LETTER:
default:
word += it;
span += it;
break;
}
}
if (word.length() || span.length()) {
if (!doemit(true, it.getBpos()))
return false;
}
return true;
}
#else // TEST driver ->
#include <unistd.h>
#include <errno.h>
#include <fcntl.h>
#include <stdio.h>
#include <iostream>
#include "textsplit.h"
#include "readfile.h"
#include "debuglog.h"
using namespace std;
// A small class to hold state while splitting text
class mySplitterCB : public TextSplitCB {
int first;
public:
mySplitterCB() : first(0) {}
bool takeword(const std::string &term, int pos, int bs, int be) {
if (first) {
printf("%3s %-20s %4s %4s\n", "pos", "Term", "bs", "be");
first = 0;
}
printf("%3d %-20s %4d %4d\n", pos, term.c_str(), bs, be);
return true;
}
};
static string teststring =
"Un bout de texte \nnormal. 2eme phrase.3eme;quatrieme.\n"
"\"Jean-Francois Dockes\" <jfd@okyz.com>\n"
"n@d @net .net t@v@c c# c++ o'brien 'o'brien' l'ami\n"
"134 +134 -14 -1.5 +1.5 1.54e10 1,2 1,2e30\n"
"@^#$(#$(*)\n"
"192.168.4.1 one\n\rtwo\r"
"Debut-\ncontinue\n"
"[olala][ululu] (valeur) (23)\n"
"utf-8 ucs-4�� \\nodef\n"
"','this\n"
" ,able,test-domain "
" -wl,--export-dynamic "
" ~/.xsession-errors "
;
static string teststring1 = " 124, ";
static string thisprog;
static string usage =
" textsplit [opts] [filename]\n"
" -q: query mode\n"
" if filename is 'stdin', will read stdin for data (end with ^D)\n"
" \n\n"
;
static void
Usage(void)
{
cerr << thisprog << ": usage:\n" << usage;
exit(1);
}
static int op_flags;
#define OPT_q 0x1
int main(int argc, char **argv)
{
thisprog = argv[0];
argc--; argv++;
while (argc > 0 && **argv == '-') {
(*argv)++;
if (!(**argv))
/* Cas du "adb - core" */
Usage();
while (**argv)
switch (*(*argv)++) {
case 'q': op_flags |= OPT_q; break;
default: Usage(); break;
}
argc--; argv++;
}
DebugLog::getdbl()->setloglevel(DEBDEB1);
DebugLog::setfilename("stderr");
mySplitterCB cb;
TextSplit splitter(&cb, (op_flags&OPT_q) ? true: false);
if (argc == 1) {
string data;
const char *filename = *argv++; argc--;
if (!strcmp(filename, "stdin")) {
char buf[1024];
int nread;
while ((nread = read(0, buf, 1024)) > 0) {
data.append(buf, nread);
}
} else if (!file_to_string(filename, data))
exit(1);
splitter.text_to_words(data);
} else {
cout << endl << teststring << endl << endl;
splitter.text_to_words(teststring);
}
}
#endif // TEST