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
|
/*** symbols.c ****************************************************************
**
** This file is part of BibTool.
** It is distributed under the GNU General Public License.
** See the file COPYING for details.
**
** (c) 1996-2020 Gerd Neugebauer
**
** Net: gene@gerd-neugebauer.de
**
** 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, 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., 675 Mass Ave, Cambridge, MA 02139, USA.
**
**-----------------------------------------------------------------------------
** Description:
** This module contains functions which deal with symbols and
** general memory management.
** This module implements a single symbol table.
**
** This module required initialization before all functions can
** be used. Especially the symbol table does not exist before
** initialization.
**
******************************************************************************/
#include <bibtool/general.h>
#include <bibtool/symbols.h>
#include <bibtool/error.h>
#include "config.h"
/*-----------------------------------------------------------------------------
** Typedef*: SymTab
** Purpose: This is the pointer type representing an entry in the symbol
** table. It contains a string and some integers.
**
**___________________________________________________ */
typedef struct STAB /* */
{ Symbol st_name; /* The symbol itself */
#ifndef COMPLEX_SYMBOL
int st_count; /* */
#endif
struct STAB *st_next; /* Pointer to the next item. */
} *SymTab;
/*-----------------------------------------------------------------------------
** Macro*: NextSymTab()
** Type: SymTab
** Purpose: The next |SymTab| of the argument. This macro
** can also be used as lvalue.
** Arguments:
** ST Current |SymTab|
** Returns: The next |SymTab| or |NULL|.
**___________________________________________________ */
#define NextSymTab(ST) ((ST)->st_next)
/*-----------------------------------------------------------------------------
** Macro*: SymTabCount()
** Type: int
** Purpose: The count slot of a |SymTab|. This macro
** can also be used as lvalue.
** Arguments:
** ST Current |SymTab|
** Returns: The count slot of |ST|.
**___________________________________________________ */
#ifdef COMPLEX_SYMBOL
#define SymTabCount(SYMTAB) SymbolCount(SymTabSymbol(SYMTAB))
#define SymCount(SYM,SYMTAB) SymbolCount(SymTabSymbol(SYMTAB))
#else
#define SymTabCount(SYMTAB) ((SYMTAB)->st_count)
#define SymCount(SYM,SYMTAB) SymTabCount(SYMTAB)
#endif
/*-----------------------------------------------------------------------------
** Macro*: SymTabSymbol()
** Type: Symbol
** Purpose: The name slot of a |SymTab|, i.e.\ the string
** representation. This macro can also be used as lvalue.
** Arguments:
** ST Current |SymTab|
** Returns: The name slot of |ST|.
**___________________________________________________ */
#define SymTabSymbol(ST) ((ST)->st_name)
/*****************************************************************************/
/* Internal Programs */
/*===========================================================================*/
#ifdef __STDC__
#define _ARG(A) A
#else
#define _ARG(A) ()
#endif
Symbol symbol _ARG((String s)); /* symbols.c */
Symbol sym_extract _ARG((String *sp, bool lowercase));/* symbols.c */
char * new_string _ARG((char * s)); /* symbols.c */
static SymTab new_sym_tab _ARG((String value)); /* symbols.c */
static int hashindex _ARG((String s)); /* symbols.c */
void init_symbols _ARG((void)); /* symbols.c */
void sym_del _ARG((Symbol sym)); /* symbols.c */
#ifdef SYMBOL_DUMP
void sym_dump _ARG((void)); /* symbols.c */
#endif
void sym_gc _ARG((void)); /* symbols.c */
void sym_unlink _ARG((Symbol s)); /* symbols.c */
/*****************************************************************************/
/* External Programs */
/*===========================================================================*/
#ifdef HASH_TABLE_SIZE
#define HASHMAX HASH_TABLE_SIZE
#else
#define HASHMAX 307
#endif
String s_empty = (String)"";
Symbol sym_empty = NO_SYMBOL; /* */
Symbol sym_space = NO_SYMBOL; /* */
Symbol sym_star = NO_SYMBOL; /* */
Symbol sym_crossref = NO_SYMBOL; /* */
Symbol sym_xdata = NO_SYMBOL; /* */
Symbol sym_xref = NO_SYMBOL; /* */
Symbol sym_qqq = NO_SYMBOL; /* */
Symbol sym_comma = NO_SYMBOL; /* */
Symbol sym_double_quote = NO_SYMBOL; /* */
Symbol sym_open_brace = NO_SYMBOL; /* */
Symbol sym_close_brace = NO_SYMBOL; /* */
Symbol sym_et = NO_SYMBOL; /* */
Symbol sym_key = NO_SYMBOL; /* */
Symbol sym_sortkey = NO_SYMBOL; /* */
/*****************************************************************************/
/*** Misc string allocation routine ***/
/*****************************************************************************/
/*-----------------------------------------------------------------------------
** Function: new_string()
** Purpose: Allocate a space for a string and copy the argument
** there. Note this is just a new copy of the memory not
** a symbol!
**
** If no more memory is available then an error is raised
** and the program is terminated.
** Arguments:
** s String to duplicate
** Returns: Pointer to newly allocated memory containing a
** duplicate of the argument string.
**___________________________________________________ */
char * new_string(s) /* */
register char * s; /* */
{ register char * t; /* */
if ( (t=malloc((size_t)strlen(s) + 1)) == NULL ) /* */
{ OUT_OF_MEMORY("string"); } /* */
(void)strcpy(t, s); /* */
return t; /* */
} /*------------------------*/
/*****************************************************************************/
/*** Symbol Table Section ***/
/*****************************************************************************/
/*-----------------------------------------------------------------------------
** Function*: new_sym_tab()
** Purpose: Allocate a new |SymTab| structure and fill it with initial
** values.
**
** If no more memory is available then an error is raised
** and the program is terminated.
** Arguments:
** value String value of the |SymTab| node.
** Returns: Pointer to a new instance of a |SymTab|.
**___________________________________________________ */
static SymTab new_sym_tab(value) /* */
String value; /* */
{ register SymTab new_symtab; /* */
Symbol sym; /* */
/* */
if ((new_symtab=(SymTab)malloc(sizeof(struct STAB))) == 0L)/* */
{ OUT_OF_MEMORY("SymTab"); } /* */
/* */
#ifdef COMPLEX_SYMBOL
if ((sym=(Symbol)malloc(sizeof(sSymbol))) /* */
== NO_SYMBOL) /* */
{ OUT_OF_MEMORY("Symbol"); } /* */
SymbolValue(sym) = newString(value); /* */
#else
sym = newString(value); /* */
#endif
SymTabSymbol(new_symtab) = sym; /* */
SymCount(sym, new_symtab) = 1; /* */
NextSymTab(new_symtab) = (SymTab)NULL; /* */
return new_symtab; /* */
} /*------------------------*/
/*-----------------------------------------------------------------------------
** Function*: hashindex()
** Purpose: Compute the sum of ASCII values modulo |HASHMAX|
** to be used as an hash index.
** Arguments:
** s string to be analyzed.
** Returns: hash index
**___________________________________________________ */
static int hashindex(s) /* */
String s; /* */
{ int index = 0; /* */
while (*s) index = (index + *(s++)) % HASHMAX; /* */
return ( index < 0 ? -index : index ); /* */
} /*------------------------*/
/*-----------------------------------------------------------------------------
** Variable*: sym_tab
** Purpose:
**
**___________________________________________________ */
static SymTab sym_tab[HASHMAX]; /* */
/*-----------------------------------------------------------------------------
** Function: init_symbols()
** Purpose: Initialize the symbols module.
** The symbol table is cleared. This is not secure when
** the symbols have already been initialized because it
** would lead to a memory leak and a violation of the
** symbol comparison assumption. Thus this case is caught
** and nothing is done when the initialization seems to
** be requested for the second time.
**
** If no more memory is available then an error is raised
** and the program is terminated.
**
** Note that this function is for internal purposes
** only. The normal user should call |init_bibtool()|
** instead.
** Arguments: none
** Returns: nothing
**___________________________________________________ */
void init_symbols() /* */
{ register int i; /* */
/* */
if (sym_empty) return; /* */
/* */
for (i = 0; i < HASHMAX; i++) sym_tab[i] = NULL; /* */
/* */
sym_empty = symbol((String)s_empty); /* */
sym_space = symbol((String)" "); /* */
sym_star = symbol((String)"*"); /* */
sym_crossref = symbol((String)"crossref"); /* */
sym_xref = symbol((String)"xref"); /* */
sym_xdata = symbol((String)"xdata"); /* */
sym_qqq = symbol((String)"???"); /* */
sym_comma = symbol((String)","); /* */
sym_double_quote = symbol((String)"\""); /* */
sym_open_brace = symbol((String)"{"); /* */
sym_close_brace = symbol((String)"}"); /* */
sym_et = symbol((String)"&"); /* */
sym_key = symbol((String)"$key"); /* */
sym_sortkey = symbol((String)"$sortkey"); /* */
} /*------------------------*/
#if defined(DEBUG) || defined(COMPLEX_SYMBOL)
/*-----------------------------------------------------------------------------
** Function*: get_sym_tab()
** Type: SymTab
** Purpose:
**
** Arguments:
** sym the symbol to search for
** Returns:
**___________________________________________________ */
static SymTab* get_sym_tab(sym) /* */
register Symbol sym; /* */
{ register SymTab *stp; /* */
/* */
if (sym == NO_SYMBOL) return NULL; /* ignore dummies. */
/* */
for (stp = &sym_tab[hashindex(SymbolValue(sym))];/* */
*stp != NULL; /* */
stp = &NextSymTab(*stp) ) /* */
{ if (sym == SymTabSymbol(*stp)) /* */
{ DebugPrint2("Symbol found ", /* */
SymbolValue(sym)); /* */
return stp; /* */
} /* */
} /* */
/* */
return NULL; /* */
} /*------------------------*/
#endif
/*-----------------------------------------------------------------------------
** Function: symbol()
** Purpose: Add a symbol to the global symbol table. If the string
** already has a symbol assigned to it then this symbol
** is returned. If the symbol is not static then the use
** count is incremented by |count|.
**
** If the symbol does not exist already then a new symbol
** is added to the symbol table and the use count is
** initialized to |count|. A negative value for |count|
** indicates that a static symbol is requested. A static
** symbol will never be deleted from the symbol table.
** Static can be used at places where one does not care
** about the memory occupied.
**
** If no more memory is available then an error is raised
** and the program is terminated.
**
** See also the macro |symbol()| in |symbols.h| for a
** convenient alternative to this function.
** Arguments:
** s String which should be translated into a symbol.
** Returns: The new symbol.
**___________________________________________________ */
Symbol symbol(s) /* */
String s; /* */
{ register SymTab *stp; /* */
Symbol sym; /* */
/* */
if (s == StringNULL) return NO_SYMBOL; /* ignore dummies. */
/* */
DebugPrint2("Lookup symbol ", s); /* */
/* */
for ( stp = &sym_tab[hashindex(s)]; /* */
*stp != NULL; /* */
stp = &NextSymTab(*stp) ) /* */
{ sym = SymTabSymbol(*stp); /* */
DebugPrintF3("\tlooking at '%s' == '%s'\n", /* */
(char*)s, (char*)SymbolValue(sym)); /* */
if (strcmp((char*)s, /* */
(char*)SymbolValue(sym)) == 0 ) /* */
{ DebugPrint2("Symbol found ", /* */
SymbolValue(sym)); /* */
SymCount(sym,*stp)++; /* */
return sym; /* */
} /* */
} /* */
/* */
*stp = new_sym_tab(s); /* */
DebugPrint2("Symbol created ", /* */
SymbolValue(SymTabSymbol(*stp))); /* */
return SymTabSymbol(*stp); /* */
} /*------------------------*/
/*-----------------------------------------------------------------------------
** Function: sym_unlink()
** Purpose: Free a symbol since it is no longer used.
** This does not mean that the memory is also freed. The
** symbol can be static or used at other places. The real
** free operation requires the garbage collector
** |sym_gc()| to be called.
**
** If the argument is |NULL| or an arbitrary string (no
** symbol) then this case is also dealt with.
** Arguments:
** sym Symbol to be released.
** Returns: nothing
**___________________________________________________ */
void sym_unlink(sym) /* */
register Symbol sym; /* */
{ /* */
if (sym == NO_SYMBOL) return; /* ignore dummies. */
#ifdef COMPLEX_SYMBOL
if (--SymbolCount(sym) > 0) return; /* double check used. */
#else
/* */
#ifdef DEBUG
if (get_sym_tab(sym) == NULL) /* */
{ ErrPrintF("*** Attempt to free an undefined symbol: %s\n",/* */
SymbolValue(sym)); /* */
} /* */
#endif
#endif
} /*------------------------*/
/*-----------------------------------------------------------------------------
** Constant: SYM_PIPE_SIZE
** Type:
** Purpose:
**
** Returns:
**___________________________________________________ */
#define SYM_PIPE_SIZE 32
#ifdef COMPLEX_SYMBOL
static Symbol sym_pipe[SYM_PIPE_SIZE];
static int sym_pipe_ptr = 0;
#endif
/*-----------------------------------------------------------------------------
** Function: sym_del()
** Type: void
** Purpose:
**
** Arguments:
** sym
** Returns: nothing
**___________________________________________________ */
void sym_del(sym) /* */
Symbol sym; /* */
{ /* */
#ifdef COMPLEX_SYMBOL
SymTab *stp; /* */
SymTab st; /* */
/* */
sym_pipe[sym_pipe_ptr] = sym; /* */
if ( ++sym_pipe_ptr < SYM_PIPE_SIZE) return; /* */
/* */
while (--sym_pipe_ptr > 0) /* */
{ sym = sym_pipe[sym_pipe_ptr]; /* */
if (SymbolCount(sym) > 0) continue; /* */
/* */
stp = get_sym_tab(sym); /* */
if (stp == NULL) continue; /* */
st = *stp; /* */
*stp = NextSymTab(st); /* */
free(st); /* */
free(SymbolValue(sym)); /* */
free(sym); /* */
} /* */
#endif
} /*------------------------*/
/*-----------------------------------------------------------------------------
** Function*: sym_gc()
** Purpose: This is the garbage collector. It analyzes the symbol
** table and releases all |SymbolTab| nodes not needed
** any more.
**
** Right now it is purely experimental. Better let your
** hands off.
**
** Arguments: none
** Returns: nothing
**___________________________________________________ */
void sym_gc() /* */
{
#ifdef COMPLEX_SYMBOL
#else
register SymTab st, st2; /* */
register int i; /* */
/* */
for ( i = 0; i < HASHMAX; i++ ) /* */
{ /* */
while (sym_tab[i] && /* */
SymTabCount(sym_tab[i]) <= 0) /* */
{ st = sym_tab[i]; /* */
sym_tab[i] = NextSymTab(st); /* */
free(SymTabSymbol(st)); /* */
free(st); /* */
} /* */
st = sym_tab[i]; /* */
if ( st ) /* */
{ /* */
while ( (st2=NextSymTab(st)) != NULL && /* */
SymTabCount(st) <= 0 ) /* */
{ NextSymTab(st) = NextSymTab(st2); /* */
free(SymTabSymbol(st2)); /* */
free(st2); /* */
} /* */
} /* */
} /* */
#endif
} /*------------------------*/
/*-----------------------------------------------------------------------------
** Function: sym_extract()
** Purpose: Extract a symbol from a string.
** Arguments:
** sp pointer to the string
** lowercase indicate that lowering is requested
** Returns:
**___________________________________________________ */
Symbol sym_extract(sp, lowercase) /* */
register String *sp; /* pointer to first char */
bool lowercase; /* */
{ Uchar c; /* */
String t = *sp; /* */
Symbol sym; /* */
/* */
while (is_allowed(**sp)) (*sp)++; /* */
c = **sp; /* */
**sp = '\0'; /* */
if (lowercase) /* */
{ t = lower(newString(t)); /* */
sym = symbol(t); /* */
free((void *)t); /* */
} else { /* */
sym = symbol(t); /* */
} /* */
**sp = c; /* */
return sym; /* */
} /*------------------------*/
/*-----------------------------------------------------------------------------
** Function: free_sym_array()
** Type: void
** Purpose:
**
** Arguments:
** sym_arr symbol array
** Returns: nothing
**___________________________________________________ */
void free_sym_array(sym_arr) /* */
Symbol *sym_arr; /* */
{ Symbol *a; /* */
for (a = sym_arr; *a; a++) /* */
{ if (*a) UnlinkSymbol(*a); } /* */
free(sym_arr); /* */
} /*------------------------*/
#ifdef SYMBOL_DUMP
/*-----------------------------------------------------------------------------
** Function: sym_dump()
** Purpose: Dump the symbol table to the error stream---see module
** |error.c|.
** The symbols are printed according to their hash value
** and the sequence they are occurring in the buckets. A
** summary of the memory used is also printed.
** Arguments: none
** Returns: nothing
**___________________________________________________ */
void sym_dump() /* */
{ register int i,l; /* */
register SymTab st; /* */
register long len = 0l; /* */
register long cnt = 0l; /* */
register long used = 0l; /* */
/* */
for ( i = 0; i < HASHMAX; i++ ) /* */
{ for ( st = sym_tab[i]; st; st=NextSymTab(st) ) /* */
{ ErrPrintF2("--- BibTool symbol %4d %s\n", /* */
SymTabCount(st), /* */
SymbolValue(SymTabSymbol(st))); /* */
l = symlen(SymTabSymbol(st)) + 1; /* */
len += l; /* */
used += l * SymTabCount(st); /* */
++cnt; /* */
} /* */
} /* */
ErrPrintF2("--- BibTool symbol table: %ld bytes for %ld symbols\n",/* */
len, cnt); /* */
ErrPrintF("--- BibTool symbol table emulates %ld bytes\n",/* */
used); /* */
} /*------------------------*/
#endif
|