1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648
|
/* liblouis Braille Translation and Back-Translation Library
Copyright (C) 2015 Bert Frees
This file is part of liblouis.
liblouis is free software: you can redistribute it and/or modify it
under the terms of the GNU Lesser General Public License as published
by the Free Software Foundation, either version 2.1 of the License, or
(at your option) any later version.
liblouis 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
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with liblouis. If not, see <http://www.gnu.org/licenses/>.
*/
/**
* @file
* @brief Find translation tables
*/
#include <config.h>
#include <stdlib.h>
#include <string.h>
#include <stdio.h>
#include <dirent.h>
#include <sys/stat.h>
#include "louis.h"
#include "findTable.h"
/* =============================== LIST =================================== */
typedef struct List
{
void * head;
void (* free)(void *);
struct List * tail;
} List;
/**
* Returns a list with the element `x' added to `list'. Returns a sorted list
* if `cmp' is not NULL and if `list' is also sorted. New elements replace
* existing ones if they are equal according to `cmp'. If `cmp' is NULL,
* elements are simply prepended to the list. The function `dup' is used to
* duplicate elements before they are added to the list. If `free' function is
* used to free elements when they are removed from the list. The returned
* list must be freed by the caller.
*/
static List *
list_conj(List * list,
void * x,
int (* cmp)(void *, void *),
void * (* dup)(void *),
void (* free)(void *))
{
if (!list)
{
list = malloc(sizeof(List));
list->head = dup ? dup(x) : x;
list->free = free;
list->tail = NULL;
return list;
}
else if (!cmp)
{
List * l = malloc(sizeof(List));
l->head = dup ? dup(x) : x;
l->free = free;
l->tail = list;
return l;
}
else
{
List * l1 = list;
List * l2 = NULL;
while (l1)
{
int c = cmp(l1->head, x);
if (c > 0)
break;
else if (c < 0)
{
l2 = l1;
l1 = l2->tail;
}
else
{
if (x != l1->head && !dup && free)
free(x);
return list;
}
}
List * l3 = malloc(sizeof(List));
l3->head = dup? dup(x) : x;
l3->free = free;
l3->tail = l1;
if (!l2)
list = l3;
else
l2->tail = l3;
return list;
}
}
/**
* Free an instance of type List.
*/
static void
list_free(List * list)
{
if (list)
{
if (list->free)
list->free(list->head);
list_free(list->tail);
free(list);
}
}
/**
* Sort a list based on a comparison function.
*/
static List *
list_sort(List * list, int (* cmp)(void *, void *))
{
List * newList = NULL;
List * l;
for (l = list; l; l = l->tail)
{
newList = list_conj(newList, l->head, cmp, NULL, l->free);
l->free = NULL;
}
list_free(list);
return newList;
}
/**
* Get the size of a list.
*/
static int
list_size(List * list)
{
int len = 0;
List * l;
for (l = list; l; l = l->tail)
len++;
return len;
}
/**
* Convert a list into a NULL terminated array.
*/
static void **
list_toArray(List * list, void * (* dup)(void *))
{
void ** array;
List * l;
int i;
array = malloc((1 + list_size(list)) * sizeof(void *));
i = 0;
for (l = list; l; l = l->tail)
array[i++] = dup ? dup(l->head) : l->head;
array[i] = NULL;
return array;
}
/* ============================== FEATURE ================================= */
typedef struct
{
char * key;
char * val;
} Feature;
typedef struct
{
Feature feature;
int importance;
} FeatureWithImportance;
typedef struct
{
char * name;
List * features;
} TableMeta;
/**
* Create an instance of type Feature.
* The `key' and `val' strings are duplicated. Leaving out the `val'
* argument results in a value of "yes".
*/
static Feature
feature_new(const char * key, const char * val)
{
static char * YES = "yes";
Feature f;
f.key = strdup(key);
f.val = strdup(val ? val : YES);
return f;
}
/**
* Free an instance of type Feature
*/
static void
feature_free(Feature * f)
{
if (f)
{
free(f->key);
free(f->val);
free(f);
}
}
/* ======================================================================== */
/**
* Sort features based on their keys.
*/
static int
cmpKeys(Feature * f1, Feature * f2)
{
return strcmp(f1->key, f2->key);
}
/**
* Compute the match quotient of the features in a query against the features in a table's metadata.
*
* The features are assumed to be sorted and to have no duplicate
* keys. The query's features must be of type FeatureWithImportance.
* How a feature contributes to the match quotient depends on its
* importance, on whether the feature is undefined, defined with the
* same value (positive match), or defined with a different value
* (negative match), and on the `fuzzy' argument. If the `fuzzy'
* argument evaluates to true, negative matches and undefined features
* get a lower penalty.
*/
static int
matchFeatureLists(const List * query, const List * tableFeatures, int fuzzy)
{
static int POS_MATCH = 10;
static int NEG_MATCH = -100;
static int UNDEFINED = -20;
static int EXTRA = -1;
static int POS_MATCH_FUZZY = 10;
static int NEG_MATCH_FUZZY = -25;
static int UNDEFINED_FUZZY = -5;
static int EXTRA_FUZZY = -1;
int posMatch, negMatch, undefined, extra;
if (!fuzzy)
{
posMatch = POS_MATCH;
negMatch = NEG_MATCH;
undefined = UNDEFINED;
extra = EXTRA;
}
else
{
posMatch = POS_MATCH_FUZZY;
negMatch = NEG_MATCH_FUZZY;
undefined = UNDEFINED_FUZZY;
extra = EXTRA_FUZZY;
}
int quotient = 0;
const List * l1 = query;
const List * l2 = tableFeatures;
while (1)
{
if (!l1)
{
if (!l2)
break;
quotient += extra;
l2 = l2->tail;
}
else if (!l2)
{
quotient += undefined;
l1 = l1->tail;
}
else
{
int cmp = cmpKeys(l1->head, l2->head);
if (cmp < 0)
{
quotient += undefined;
l1 = l1->tail;
}
else if (cmp > 0)
{
quotient += extra;
l2 = l2->tail;
}
else
{
if (strcmp(((Feature *)l1->head)->val, ((Feature *)l2->head)->val) == 0)
quotient += posMatch;
else
quotient += negMatch;
l1 = l1->tail;
l2 = l2->tail;
}
}
}
return quotient;
}
/**
* Return true if a character matches [0-9A-Za-z_-]
*/
static int
isIdentChar(char c)
{
return (c >= '0' && c <= '9')
|| (c >= 'A' && c <= 'Z')
|| (c >= 'a' && c <= 'z')
|| c == '-'
|| c == '_';
}
/**
* Parse a table query into a list of features. Features defined first get a
* higher importance.
*/
static List *
parseQuery(const char * query)
{
List * features = NULL;
const char * key = NULL;
const char * val = NULL;
size_t keySize = 0;
size_t valSize = 0;
const char * c;
int pos = 0;
while (1)
{
c = &query[pos++];
if (*c == ' ' || *c == '\t' || *c == '\n' | *c == '\0')
{
if (key)
{
char * k = strndup(key, keySize);
char * v = val ? strndup(val, valSize) : NULL;
FeatureWithImportance f = { feature_new(k, v), 0 };
logMessage(LOG_DEBUG, "Query has feature '%s:%s'", f.feature.key, f.feature.val);
features = list_conj(features, memcpy(malloc(sizeof(f)), &f, sizeof(f)),
NULL, NULL, (void (*)(void *))feature_free);
free(k);
free(v);
key = val = NULL;
keySize = valSize = 0;
}
if (*c == '\0')
break;
}
else if (*c == ':')
{
if (!key || val)
goto compile_error;
else
{
c = &query[pos++];
if (isIdentChar(*c))
{
val = c;
valSize = 1;
}
else
goto compile_error;
}
}
else if (isIdentChar(*c))
{
if (val)
valSize++;
else if (key)
keySize++;
else
{
key = c;
keySize = 1;
}
}
else
goto compile_error;
}
int k = 1;
List * l;
for (l = features; l; l = l->tail)
{
FeatureWithImportance * f = l->head;
f->importance = k++;
}
return list_sort(features, (int (*)(void *, void *))cmpKeys);
compile_error:
logMessage(LOG_ERROR, "Unexpected character '%c' at position %d", c, pos);
list_free(features);
return NULL;
}
/**
* Convert a widechar string to a normal string.
*/
static char *
widestrToStr(const widechar * str, size_t n)
{
char * result = malloc((1 + n) * sizeof(char));
int k;
for (k = 0; k < n; k++)
result[k] = str[k];
result[k] = '\0';
return result;
}
/**
* Extract a list of features from a table.
*/
static List *
analyzeTable(const char * table)
{
static char fileName[MAXSTRING];
char ** resolved;
List * features = NULL;
FileInfo info;
int k;
resolved = resolveTable(table, NULL);
if (resolved == NULL)
{
logMessage(LOG_ERROR, "Cannot resolve table '%s'", table);
return NULL;
}
sprintf(fileName, "%s", *resolved);
k = 0;
for (k = 0; resolved[k]; k++)
free(resolved[k]);
free(resolved);
if (k > 1)
{
logMessage(LOG_ERROR, "Table '%s' resolves to more than one file", table);
return NULL;
}
info.fileName = fileName;
info.encoding = noEncoding;
info.status = 0;
info.lineNumber = 0;
if ((info.in = fopen(info.fileName, "rb")))
{
while (getALine(&info))
{
if (info.linelen == 0);
else if (info.line[0] == '#')
{
if (info.linelen >= 2 && info.line[1] == '+')
{
widechar * key = NULL;
widechar * val = NULL;
size_t keySize = 0;
size_t valSize = 0;
info.linepos = 2;
if (info.linepos < info.linelen && isIdentChar(info.line[info.linepos]))
{
key = &info.line[info.linepos];
keySize = 1;
info.linepos++;
while (info.linepos < info.linelen && isIdentChar(info.line[info.linepos]))
{
keySize++;
info.linepos++;
}
if (info.linepos < info.linelen && info.line[info.linepos] == ':')
{
info.linepos++;
while (info.linepos < info.linelen
&& (info.line[info.linepos] == ' ' || info.line[info.linepos] == '\t'))
info.linepos++;
if (info.linepos < info.linelen && isIdentChar(info.line[info.linepos]))
{
val = &info.line[info.linepos];
valSize = 1;
info.linepos++;
while (info.linepos < info.linelen && isIdentChar(info.line[info.linepos]))
{
valSize++;
info.linepos++;
}
}
else
goto compile_error;
}
if (info.linepos == info.linelen)
{
char * k = widestrToStr(key, keySize);
char * v = val ? widestrToStr(val, valSize) : NULL;
Feature f = feature_new(k, v);
logMessage(LOG_DEBUG, "Table has feature '%s:%s'", f.key, f.val);
features = list_conj(features, memcpy(malloc(sizeof(f)), &f, sizeof(f)),
NULL, NULL, (void (*)(void *))feature_free);
free(k);
free(v);
}
else
goto compile_error;
}
else
goto compile_error;
}
}
else
break;
}
fclose(info.in);
}
else
logMessage (LOG_ERROR, "Cannot open table '%s'", info.fileName);
return list_sort(features, (int (*)(void *, void *))cmpKeys);
compile_error:
if (info.linepos < info.linelen)
logMessage(LOG_ERROR, "Unexpected character '%c' on line %d, column %d",
info.line[info.linepos],
info.lineNumber,
info.linepos);
else
logMessage(LOG_ERROR, "Unexpected newline on line %d", info.lineNumber);
list_free(features);
return NULL;
}
static List * tableIndex = NULL;
void EXPORT_CALL
lou_indexTables(const char ** tables)
{
const char ** table;
list_free(tableIndex);
tableIndex = NULL;
for (table = tables; *table; table++)
{
logMessage(LOG_DEBUG, "Analyzing table %s", *table);
List * features = analyzeTable(*table);
if (features)
{
TableMeta m = { strdup(*table), features };
tableIndex = list_conj(tableIndex, memcpy(malloc(sizeof(m)), &m, sizeof(m)), NULL, NULL, free);
}
}
if (!tableIndex)
logMessage(LOG_WARN, "No tables were indexed");
}
#ifdef _WIN32
#define DIR_SEP '\\'
#else
#define DIR_SEP '/'
#endif
/**
* Returns the list of files found on searchPath, where searchPath is a
* comma-separated list of directories.
*/
static List *
listFiles(char * searchPath)
{
List * list = NULL;
char * dirName;
DIR * dir;
struct dirent * file;
static char fileName[MAXSTRING];
struct stat info;
int pos = 0;
int n;
while (1)
{
for (n = 0; searchPath[pos + n] != '\0' && searchPath[pos + n] != ','; n++);
dirName = strndup(&searchPath[pos], n);
if ((dir = opendir(dirName)))
{
while ((file = readdir(dir)))
{
sprintf(fileName, "%s%c%s", dirName, DIR_SEP, file->d_name);
if (stat(fileName, &info) == 0 && !(info.st_mode & S_IFDIR))
{
list = list_conj(list, strdup(fileName), NULL, NULL, free);
}
}
closedir(dir);
}
else
{
logMessage(LOG_WARN, "%s is not a directory", dirName);
}
free(dirName);
pos += n;
if (searchPath[pos] == '\0')
break;
else
pos++;
}
return list;
}
char * EXPORT_CALL
lou_findTable(const char * query)
{
if (!tableIndex)
{
char * searchPath;
List * tables;
const char ** tablesArray;
logMessage(LOG_WARN, "Tables have not been indexed yet. Indexing LOUIS_TABLEPATH.");
searchPath = getTablePath();
tables = listFiles(searchPath);
tablesArray = (const char **)list_toArray(tables, NULL);
lou_indexTables(tablesArray);
free(searchPath);
list_free(tables);
free(tablesArray);
}
List * queryFeatures = parseQuery(query);
int bestQuotient = 0;
char * bestMatch = NULL;
List * l;
for (l = tableIndex; l; l = l->tail)
{
TableMeta * table = l->head;
int q = matchFeatureLists(queryFeatures, table->features, 0);
if (q > bestQuotient)
{
bestQuotient = q;
bestMatch = strdup(table->name);
}
}
if (bestMatch)
{
logMessage(LOG_INFO, "Best match: %s (%d)", bestMatch, bestQuotient);
return bestMatch;
}
else
{
logMessage(LOG_INFO, "No table could be found for query '%s'", query);
return NULL;
}
}
|