/*
* libpinyin
* Library to deal with pinyin.
*
* Copyright (C) 2010 Peng Wu
*
* 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 3 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, see .
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include
#include
#include
#include "pinyin_internal.h"
#include "utils_helper.h"
void print_help(){
printf("Usage: ngseg [--generate-extra-enter] [-o outputfile] [inputfile]\n");
}
static gboolean gen_extra_enter = FALSE;
static gchar * outputfile = NULL;
static GOptionEntry entries[] =
{
{"outputfile", 'o', 0, G_OPTION_ARG_FILENAME, &outputfile, "output", "filename"},
{"generate-extra-enter", 0, 0, G_OPTION_ARG_NONE, &gen_extra_enter, "generate ", NULL},
{NULL}
};
/* n-gram based sentence segment. */
/* Note:
* Currently libpinyin supports ucs4 characters.
* This is a pre-processor tool for raw corpus,
* and skips non-Chinese characters.
*/
/* TODO:
* Try to add punctuation mark and english support,
* such as ',', '.', '?', '!', , and other punctuations.
*/
enum CONTEXT_STATE{
CONTEXT_INIT,
CONTEXT_SEGMENTABLE,
CONTEXT_UNKNOWN
};
bool deal_with_segmentable(PhraseLookup * phrase_lookup,
GArray * current_ucs4,
FILE * output){
char * result_string = NULL;
MatchResult result = g_array_new(FALSE, FALSE, sizeof(phrase_token_t));
phrase_lookup->get_best_match(current_ucs4->len,
(ucs4_t *) current_ucs4->data, result);
phrase_lookup->convert_to_utf8(result, result_string);
if (result_string) {
fprintf(output, "%s\n", result_string);
} else {
char * tmp_string = g_ucs4_to_utf8
( (ucs4_t *) current_ucs4->data, current_ucs4->len,
NULL, NULL, NULL);
fprintf(stderr, "Un-segmentable sentence encountered:%s\n",
tmp_string);
g_array_free(result, TRUE);
return false;
}
g_array_free(result, TRUE);
g_free(result_string);
return true;
}
bool deal_with_unknown(GArray * current_ucs4, FILE * output){
char * result_string = g_ucs4_to_utf8
( (ucs4_t *) current_ucs4->data, current_ucs4->len,
NULL, NULL, NULL);
fprintf(output, "%d %s\n", null_token, result_string);
g_free(result_string);
return true;
}
int main(int argc, char * argv[]){
FILE * input = stdin;
FILE * output = stdout;
setlocale(LC_ALL, "");
GError * error = NULL;
GOptionContext * context;
context = g_option_context_new("- n-gram segment");
g_option_context_add_main_entries(context, entries, NULL);
if (!g_option_context_parse(context, &argc, &argv, &error)) {
g_print("option parsing failed:%s\n", error->message);
exit(EINVAL);
}
if (outputfile) {
output = fopen(outputfile, "w");
if (NULL == output) {
perror("open file failed");
exit(EINVAL);
}
}
if (argc > 2) {
fprintf(stderr, "too many arguments.\n");
exit(EINVAL);
}
if (2 == argc) {
input = fopen(argv[1], "r");
if (NULL == input) {
perror("open file failed");
exit(EINVAL);
}
}
SystemTableInfo2 system_table_info;
bool retval = system_table_info.load(SYSTEM_TABLE_INFO);
if (!retval) {
fprintf(stderr, "load table.conf failed.\n");
exit(ENOENT);
}
/* init phrase table */
FacadePhraseTable3 phrase_table;
phrase_table.load(SYSTEM_PHRASE_INDEX, NULL);
/* init phrase index */
FacadePhraseIndex phrase_index;
const pinyin_table_info_t * phrase_files =
system_table_info.get_default_tables();
if (!load_phrase_index(phrase_files, &phrase_index))
exit(ENOENT);
/* init bi-gram */
Bigram system_bigram;
system_bigram.attach(SYSTEM_BIGRAM, ATTACH_READONLY);
Bigram user_bigram;
gfloat lambda = system_table_info.get_lambda();
/* init phrase lookup */
PhraseLookup phrase_lookup(lambda,
&phrase_table, &phrase_index,
&system_bigram, &user_bigram);
CONTEXT_STATE state, next_state;
GArray * current_ucs4 = g_array_new(TRUE, TRUE, sizeof(ucs4_t));
PhraseTokens tokens;
memset(tokens, 0, sizeof(PhraseTokens));
phrase_index.prepare_tokens(tokens);
/* split the sentence */
char * linebuf = NULL; size_t size = 0; ssize_t read;
while( (read = getline(&linebuf, &size, input)) != -1 ){
if ( '\n' == linebuf[strlen(linebuf) - 1] ) {
linebuf[strlen(linebuf) - 1] = '\0';
}
/* check non-ucs4 characters */
const glong num_of_chars = g_utf8_strlen(linebuf, -1);
glong len = 0;
ucs4_t * sentence = g_utf8_to_ucs4(linebuf, -1, NULL, &len, NULL);
if ( len != num_of_chars ) {
fprintf(stderr, "non-ucs4 characters encountered:%s.\n", linebuf);
fprintf(output, "%d \n", null_token);
continue;
}
/* only new-line persists. */
if ( 0 == num_of_chars ) {
fprintf(output, "%d \n", null_token);
continue;
}
state = CONTEXT_INIT;
int result = phrase_table.search( 1, sentence, tokens);
g_array_append_val( current_ucs4, sentence[0]);
if ( result & SEARCH_OK )
state = CONTEXT_SEGMENTABLE;
else
state = CONTEXT_UNKNOWN;
for ( int i = 1; i < num_of_chars; ++i) {
int result = phrase_table.search( 1, sentence + i, tokens);
if ( result & SEARCH_OK )
next_state = CONTEXT_SEGMENTABLE;
else
next_state = CONTEXT_UNKNOWN;
if ( state == next_state ){
g_array_append_val(current_ucs4, sentence[i]);
continue;
}
assert ( state != next_state );
if ( state == CONTEXT_SEGMENTABLE )
deal_with_segmentable(&phrase_lookup, current_ucs4, output);
if ( state == CONTEXT_UNKNOWN )
deal_with_unknown(current_ucs4, output);
/* save the current character */
g_array_set_size(current_ucs4, 0);
g_array_append_val(current_ucs4, sentence[i]);
state = next_state;
}
if ( current_ucs4->len ) {
/* this seems always true. */
if ( state == CONTEXT_SEGMENTABLE )
deal_with_segmentable(&phrase_lookup, current_ucs4, output);
if ( state == CONTEXT_UNKNOWN )
deal_with_unknown(current_ucs4, output);
g_array_set_size(current_ucs4, 0);
}
/* print extra enter */
if ( gen_extra_enter )
fprintf(output, "%d \n", null_token);
g_free(sentence);
}
phrase_index.destroy_tokens(tokens);
/* print enter at file tail */
fprintf(output, "%d \n", null_token);
g_array_free(current_ucs4, TRUE);
free(linebuf);
fclose(input);
fclose(output);
return 0;
}