1 /* Copyright (C) 1989, 2000 Aladdin Enterprises. All rights reserved. */ 2 3 /*$Id: ansi2knr.c,v 1.3 2000/04/13 03:41:48 lpd Exp $*/ 4 /* Convert ANSI C function definitions to K&R ("traditional C") syntax */ 5 6 /* 7 ansi2knr is distributed in the hope that it will be useful, but WITHOUT ANY 8 WARRANTY. No author or distributor accepts responsibility to anyone for the 9 consequences of using it or for whether it serves any particular purpose or 10 works at all, unless he says so in writing. Refer to the GNU General Public 11 License (the "GPL") for full details. 12 13 Everyone is granted permission to copy, modify and redistribute ansi2knr, 14 but only under the conditions described in the GPL. A copy of this license 15 is supposed to have been given to you along with ansi2knr so you can know 16 your rights and responsibilities. It should be in a file named COPYLEFT, 17 or, if there is no file named COPYLEFT, a file named COPYING. Among other 18 things, the copyright notice and this notice must be preserved on all 19 copies. 20 21 We explicitly state here what we believe is already implied by the GPL: if 22 the ansi2knr program is distributed as a separate set of sources and a 23 separate executable file which are aggregated on a storage medium together 24 with another program, this in itself does not bring the other program under 25 the GPL, nor does the mere fact that such a program or the procedures for 26 constructing it invoke the ansi2knr executable bring any other part of the 27 program under the GPL. 28 */ 29 30 /* 31 * Usage: 32 ansi2knr [--filename FILENAME] [INPUT_FILE [OUTPUT_FILE]] 33 * --filename provides the file name for the #line directive in the output, 34 * overriding input_file (if present). 35 * If no input_file is supplied, input is read from stdin. 36 * If no output_file is supplied, output goes to stdout. 37 * There are no error messages. 38 * 39 * ansi2knr recognizes function definitions by seeing a non-keyword 40 * identifier at the left margin, followed by a left parenthesis, with a 41 * right parenthesis as the last character on the line, and with a left 42 * brace as the first token on the following line (ignoring possible 43 * intervening comments and/or preprocessor directives), except that a line 44 * consisting of only 45 * identifier1(identifier2) 46 * will not be considered a function definition unless identifier2 is 47 * the word "void", and a line consisting of 48 * identifier1(identifier2, <<arbitrary>>) 49 * will not be considered a function definition. 50 * ansi2knr will recognize a multi-line header provided that no intervening 51 * line ends with a left or right brace or a semicolon. These algorithms 52 * ignore whitespace, comments, and preprocessor directives, except that 53 * the function name must be the first thing on the line. The following 54 * constructs will confuse it: 55 * - Any other construct that starts at the left margin and 56 * follows the above syntax (such as a macro or function call). 57 * - Some macros that tinker with the syntax of function headers. 58 */ 59 60 /* 61 * The original and principal author of ansi2knr is L. Peter Deutsch 62 * <ghost (at) aladdin.com>. Other authors are noted in the change history 63 * that follows (in reverse chronological order): 64 65 lpd 2000-04-12 backs out Eggert's changes because of bugs: 66 - concatlits didn't declare the type of its bufend argument; 67 - concatlits didn't recognize when it was inside a comment; 68 - scanstring could scan backward past the beginning of the string; when 69 - the check for \ + newline in scanstring was unnecessary. 70 71 2000-03-05 Paul Eggert <eggert (at) twinsun.com> 72 73 Add support for concatenated string literals. 74 * ansi2knr.c (concatlits): New decl. 75 (main): Invoke concatlits to concatenate string literals. 76 (scanstring): Handle backslash-newline correctly. Work with 77 character constants. Fix bug when scanning backwards through 78 backslash-quote. Check for unterminated strings. 79 (convert1): Parse character constants, too. 80 (appendline, concatlits): New functions. 81 * ansi2knr.1: Document this. 82 83 lpd 1999-08-17 added code to allow preprocessor directives 84 wherever comments are allowed 85 lpd 1999-04-12 added minor fixes from Pavel Roskin 86 <pavel_roskin (at) geocities.com> for clean compilation with 87 gcc -W -Wall 88 lpd 1999-03-22 added hack to recognize lines consisting of 89 identifier1(identifier2, xxx) as *not* being procedures 90 lpd 1999-02-03 made indentation of preprocessor commands consistent 91 lpd 1999-01-28 fixed two bugs: a '/' in an argument list caused an 92 endless loop; quoted strings within an argument list 93 confused the parser 94 lpd 1999-01-24 added a check for write errors on the output, 95 suggested by Jim Meyering <meyering (at) ascend.com> 96 lpd 1998-11-09 added further hack to recognize identifier(void) 97 as being a procedure 98 lpd 1998-10-23 added hack to recognize lines consisting of 99 identifier1(identifier2) as *not* being procedures 100 lpd 1997-12-08 made input_file optional; only closes input and/or 101 output file if not stdin or stdout respectively; prints 102 usage message on stderr rather than stdout; adds 103 --filename switch (changes suggested by 104 <ceder (at) lysator.liu.se>) 105 lpd 1996-01-21 added code to cope with not HAVE_CONFIG_H and with 106 compilers that don't understand void, as suggested by 107 Tom Lane 108 lpd 1996-01-15 changed to require that the first non-comment token 109 on the line following a function header be a left brace, 110 to reduce sensitivity to macros, as suggested by Tom Lane 111 <tgl (at) sss.pgh.pa.us> 112 lpd 1995-06-22 removed #ifndefs whose sole purpose was to define 113 undefined preprocessor symbols as 0; changed all #ifdefs 114 for configuration symbols to #ifs 115 lpd 1995-04-05 changed copyright notice to make it clear that 116 including ansi2knr in a program does not bring the entire 117 program under the GPL 118 lpd 1994-12-18 added conditionals for systems where ctype macros 119 don't handle 8-bit characters properly, suggested by 120 Francois Pinard <pinard (at) iro.umontreal.ca>; 121 removed --varargs switch (this is now the default) 122 lpd 1994-10-10 removed CONFIG_BROKETS conditional 123 lpd 1994-07-16 added some conditionals to help GNU `configure', 124 suggested by Francois Pinard <pinard (at) iro.umontreal.ca>; 125 properly erase prototype args in function parameters, 126 contributed by Jim Avera <jima (at) netcom.com>; 127 correct error in writeblanks (it shouldn't erase EOLs) 128 lpd 1989-xx-xx original version 129 */ 130 131 /* Most of the conditionals here are to make ansi2knr work with */ 132 /* or without the GNU configure machinery. */ 133 134 #if HAVE_CONFIG_H 135 # include <config.h> 136 #endif 137 138 #include <stdio.h> 139 #include <ctype.h> 140 141 #if HAVE_CONFIG_H 142 143 /* 144 For properly autoconfiguring ansi2knr, use AC_CONFIG_HEADER(config.h). 145 This will define HAVE_CONFIG_H and so, activate the following lines. 146 */ 147 148 # if STDC_HEADERS || HAVE_STRING_H 149 # include <string.h> 150 # else 151 # include <strings.h> 152 # endif 153 154 #else /* not HAVE_CONFIG_H */ 155 156 /* Otherwise do it the hard way */ 157 158 # ifdef BSD 159 # include <strings.h> 160 # else 161 # ifdef VMS 162 extern int strlen(), strncmp(); 163 # else 164 # include <string.h> 165 # endif 166 # endif 167 168 #endif /* not HAVE_CONFIG_H */ 169 170 #if STDC_HEADERS 171 # include <stdlib.h> 172 #else 173 /* 174 malloc and free should be declared in stdlib.h, 175 but if you've got a K&R compiler, they probably aren't. 176 */ 177 # ifdef MSDOS 178 # include <malloc.h> 179 # else 180 # ifdef VMS 181 extern char *malloc(); 182 extern void free(); 183 # else 184 extern char *malloc(); 185 extern int free(); 186 # endif 187 # endif 188 189 #endif 190 191 /* Define NULL (for *very* old compilers). */ 192 #ifndef NULL 193 # define NULL (0) 194 #endif 195 196 /* 197 * The ctype macros don't always handle 8-bit characters correctly. 198 * Compensate for this here. 199 */ 200 #ifdef isascii 201 # undef HAVE_ISASCII /* just in case */ 202 # define HAVE_ISASCII 1 203 #else 204 #endif 205 #if STDC_HEADERS || !HAVE_ISASCII 206 # define is_ascii(c) 1 207 #else 208 # define is_ascii(c) isascii(c) 209 #endif 210 211 #define is_space(c) (is_ascii(c) && isspace(c)) 212 #define is_alpha(c) (is_ascii(c) && isalpha(c)) 213 #define is_alnum(c) (is_ascii(c) && isalnum(c)) 214 215 /* Scanning macros */ 216 #define isidchar(ch) (is_alnum(ch) || (ch) == '_') 217 #define isidfirstchar(ch) (is_alpha(ch) || (ch) == '_') 218 219 /* Forward references */ 220 char *ppdirforward(); 221 char *ppdirbackward(); 222 char *skipspace(); 223 char *scanstring(); 224 int writeblanks(); 225 int test1(); 226 int convert1(); 227 228 /* The main program */ 229 int 230 main(argc, argv) 231 int argc; 232 char *argv[]; 233 { FILE *in = stdin; 234 FILE *out = stdout; 235 char *filename = 0; 236 char *program_name = argv[0]; 237 char *output_name = 0; 238 #define bufsize 5000 /* arbitrary size */ 239 char *buf; 240 char *line; 241 char *more; 242 char *usage = 243 "Usage: ansi2knr [--filename FILENAME] [INPUT_FILE [OUTPUT_FILE]]\n"; 244 /* 245 * In previous versions, ansi2knr recognized a --varargs switch. 246 * If this switch was supplied, ansi2knr would attempt to convert 247 * a ... argument to va_alist and va_dcl; if this switch was not 248 * supplied, ansi2knr would simply drop any such arguments. 249 * Now, ansi2knr always does this conversion, and we only 250 * check for this switch for backward compatibility. 251 */ 252 int convert_varargs = 1; 253 int output_error; 254 255 while ( argc > 1 && argv[1][0] == '-' ) { 256 if ( !strcmp(argv[1], "--varargs") ) { 257 convert_varargs = 1; 258 argc--; 259 argv++; 260 continue; 261 } 262 if ( !strcmp(argv[1], "--filename") && argc > 2 ) { 263 filename = argv[2]; 264 argc -= 2; 265 argv += 2; 266 continue; 267 } 268 fprintf(stderr, "%s: Unrecognized switch: %s\n", program_name, 269 argv[1]); 270 fprintf(stderr, usage); 271 exit(1); 272 } 273 switch ( argc ) 274 { 275 default: 276 fprintf(stderr, usage); 277 exit(0); 278 case 3: 279 output_name = argv[2]; 280 out = fopen(output_name, "w"); 281 if ( out == NULL ) { 282 fprintf(stderr, "%s: Cannot open output file %s\n", 283 program_name, output_name); 284 exit(1); 285 } 286 /* falls through */ 287 case 2: 288 in = fopen(argv[1], "r"); 289 if ( in == NULL ) { 290 fprintf(stderr, "%s: Cannot open input file %s\n", 291 program_name, argv[1]); 292 exit(1); 293 } 294 if ( filename == 0 ) 295 filename = argv[1]; 296 /* falls through */ 297 case 1: 298 break; 299 } 300 if ( filename ) 301 fprintf(out, "#line 1 \"%s\"\n", filename); 302 buf = malloc(bufsize); 303 if ( buf == NULL ) 304 { 305 fprintf(stderr, "Unable to allocate read buffer!\n"); 306 exit(1); 307 } 308 line = buf; 309 while ( fgets(line, (unsigned)(buf + bufsize - line), in) != NULL ) 310 { 311 test: line += strlen(line); 312 switch ( test1(buf) ) 313 { 314 case 2: /* a function header */ 315 convert1(buf, out, 1, convert_varargs); 316 break; 317 case 1: /* a function */ 318 /* Check for a { at the start of the next line. */ 319 more = ++line; 320 f: if ( line >= buf + (bufsize - 1) ) /* overflow check */ 321 goto wl; 322 if ( fgets(line, (unsigned)(buf + bufsize - line), in) == NULL ) 323 goto wl; 324 switch ( *skipspace(ppdirforward(more), 1) ) 325 { 326 case '{': 327 /* Definitely a function header. */ 328 convert1(buf, out, 0, convert_varargs); 329 fputs(more, out); 330 break; 331 case 0: 332 /* The next line was blank or a comment: */ 333 /* keep scanning for a non-comment. */ 334 line += strlen(line); 335 goto f; 336 default: 337 /* buf isn't a function header, but */ 338 /* more might be. */ 339 fputs(buf, out); 340 strcpy(buf, more); 341 line = buf; 342 goto test; 343 } 344 break; 345 case -1: /* maybe the start of a function */ 346 if ( line != buf + (bufsize - 1) ) /* overflow check */ 347 continue; 348 /* falls through */ 349 default: /* not a function */ 350 wl: fputs(buf, out); 351 break; 352 } 353 line = buf; 354 } 355 if ( line != buf ) 356 fputs(buf, out); 357 free(buf); 358 if ( output_name ) { 359 output_error = ferror(out); 360 output_error |= fclose(out); 361 } else { /* out == stdout */ 362 fflush(out); 363 output_error = ferror(out); 364 } 365 if ( output_error ) { 366 fprintf(stderr, "%s: error writing to %s\n", program_name, 367 (output_name ? output_name : "stdout")); 368 exit(1); 369 } 370 if ( in != stdin ) 371 fclose(in); 372 return 0; 373 } 374 375 /* 376 * Skip forward or backward over one or more preprocessor directives. 377 */ 378 char * 379 ppdirforward(p) 380 char *p; 381 { 382 for (; *p == '#'; ++p) { 383 for (; *p != '\r' && *p != '\n'; ++p) 384 if (*p == 0) 385 return p; 386 if (*p == '\r' && p[1] == '\n') 387 ++p; 388 } 389 return p; 390 } 391 char * 392 ppdirbackward(p, limit) 393 char *p; 394 char *limit; 395 { 396 char *np = p; 397 398 for (;; p = --np) { 399 if (*np == '\n' && np[-1] == '\r') 400 --np; 401 for (; np > limit && np[-1] != '\r' && np[-1] != '\n'; --np) 402 if (np[-1] == 0) 403 return np; 404 if (*np != '#') 405 return p; 406 } 407 } 408 409 /* 410 * Skip over whitespace, comments, and preprocessor directives, 411 * in either direction. 412 */ 413 char * 414 skipspace(p, dir) 415 char *p; 416 int dir; /* 1 for forward, -1 for backward */ 417 { 418 for ( ; ; ) { 419 while ( is_space(*p) ) 420 p += dir; 421 if ( !(*p == '/' && p[dir] == '*') ) 422 break; 423 p += dir; p += dir; 424 while ( !(*p == '*' && p[dir] == '/') ) { 425 if ( *p == 0 ) 426 return p; /* multi-line comment?? */ 427 p += dir; 428 } 429 p += dir; p += dir; 430 } 431 return p; 432 } 433 434 /* Scan over a quoted string, in either direction. */ 435 char * 436 scanstring(p, dir) 437 char *p; 438 int dir; 439 { 440 for (p += dir; ; p += dir) 441 if (*p == '"' && p[-dir] != '\\') 442 return p + dir; 443 } 444 445 /* 446 * Write blanks over part of a string. 447 * Don't overwrite end-of-line characters. 448 */ 449 int 450 writeblanks(start, end) 451 char *start; 452 char *end; 453 { char *p; 454 for ( p = start; p < end; p++ ) 455 if ( *p != '\r' && *p != '\n' ) 456 *p = ' '; 457 return 0; 458 } 459 460 /* 461 * Test whether the string in buf is a function definition. 462 * The string may contain and/or end with a newline. 463 * Return as follows: 464 * 0 - definitely not a function definition; 465 * 1 - definitely a function definition; 466 * 2 - definitely a function prototype (NOT USED); 467 * -1 - may be the beginning of a function definition, 468 * append another line and look again. 469 * The reason we don't attempt to convert function prototypes is that 470 * Ghostscript's declaration-generating macros look too much like 471 * prototypes, and confuse the algorithms. 472 */ 473 int 474 test1(buf) 475 char *buf; 476 { char *p = buf; 477 char *bend; 478 char *endfn; 479 int contin; 480 481 if ( !isidfirstchar(*p) ) 482 return 0; /* no name at left margin */ 483 bend = skipspace(ppdirbackward(buf + strlen(buf) - 1, buf), -1); 484 switch ( *bend ) 485 { 486 case ';': contin = 0 /*2*/; break; 487 case ')': contin = 1; break; 488 case '{': return 0; /* not a function */ 489 case '}': return 0; /* not a function */ 490 default: contin = -1; 491 } 492 while ( isidchar(*p) ) 493 p++; 494 endfn = p; 495 p = skipspace(p, 1); 496 if ( *p++ != '(' ) 497 return 0; /* not a function */ 498 p = skipspace(p, 1); 499 if ( *p == ')' ) 500 return 0; /* no parameters */ 501 /* Check that the apparent function name isn't a keyword. */ 502 /* We only need to check for keywords that could be followed */ 503 /* by a left parenthesis (which, unfortunately, is most of them). */ 504 { static char *words[] = 505 { "asm", "auto", "case", "char", "const", "double", 506 "extern", "float", "for", "if", "int", "long", 507 "register", "return", "short", "signed", "sizeof", 508 "static", "switch", "typedef", "unsigned", 509 "void", "volatile", "while", 0 510 }; 511 char **key = words; 512 char *kp; 513 unsigned len = endfn - buf; 514 515 while ( (kp = *key) != 0 ) 516 { if ( strlen(kp) == len && !strncmp(kp, buf, len) ) 517 return 0; /* name is a keyword */ 518 key++; 519 } 520 } 521 { 522 char *id = p; 523 int len; 524 /* 525 * Check for identifier1(identifier2) and not 526 * identifier1(void), or identifier1(identifier2, xxxx). 527 */ 528 529 while ( isidchar(*p) ) 530 p++; 531 len = p - id; 532 p = skipspace(p, 1); 533 if (*p == ',' || 534 (*p == ')' && (len != 4 || strncmp(id, "void", 4))) 535 ) 536 return 0; /* not a function */ 537 } 538 /* 539 * If the last significant character was a ), we need to count 540 * parentheses, because it might be part of a formal parameter 541 * that is a procedure. 542 */ 543 if (contin > 0) { 544 int level = 0; 545 546 for (p = skipspace(buf, 1); *p; p = skipspace(p + 1, 1)) 547 level += (*p == '(' ? 1 : *p == ')' ? -1 : 0); 548 if (level > 0) 549 contin = -1; 550 } 551 return contin; 552 } 553 554 /* Convert a recognized function definition or header to K&R syntax. */ 555 int 556 convert1(buf, out, header, convert_varargs) 557 char *buf; 558 FILE *out; 559 int header; /* Boolean */ 560 int convert_varargs; /* Boolean */ 561 { char *endfn; 562 char *p; 563 /* 564 * The breaks table contains pointers to the beginning and end 565 * of each argument. 566 */ 567 char **breaks; 568 unsigned num_breaks = 2; /* for testing */ 569 char **btop; 570 char **bp; 571 char **ap; 572 char *vararg = 0; 573 574 /* Pre-ANSI implementations don't agree on whether strchr */ 575 /* is called strchr or index, so we open-code it here. */ 576 for ( endfn = buf; *(endfn++) != '('; ) 577 ; 578 top: p = endfn; 579 breaks = (char **)malloc(sizeof(char *) * num_breaks * 2); 580 if ( breaks == NULL ) 581 { /* Couldn't allocate break table, give up */ 582 fprintf(stderr, "Unable to allocate break table!\n"); 583 fputs(buf, out); 584 return -1; 585 } 586 btop = breaks + num_breaks * 2 - 2; 587 bp = breaks; 588 /* Parse the argument list */ 589 do 590 { int level = 0; 591 char *lp = NULL; 592 char *rp = NULL; 593 char *end = NULL; 594 595 if ( bp >= btop ) 596 { /* Filled up break table. */ 597 /* Allocate a bigger one and start over. */ 598 free((char *)breaks); 599 num_breaks <<= 1; 600 goto top; 601 } 602 *bp++ = p; 603 /* Find the end of the argument */ 604 for ( ; end == NULL; p++ ) 605 { switch(*p) 606 { 607 case ',': 608 if ( !level ) end = p; 609 break; 610 case '(': 611 if ( !level ) lp = p; 612 level++; 613 break; 614 case ')': 615 if ( --level < 0 ) end = p; 616 else rp = p; 617 break; 618 case '/': 619 if (p[1] == '*') 620 p = skipspace(p, 1) - 1; 621 break; 622 case '"': 623 p = scanstring(p, 1) - 1; 624 break; 625 default: 626 ; 627 } 628 } 629 /* Erase any embedded prototype parameters. */ 630 if ( lp && rp ) 631 writeblanks(lp + 1, rp); 632 p--; /* back up over terminator */ 633 /* Find the name being declared. */ 634 /* This is complicated because of procedure and */ 635 /* array modifiers. */ 636 for ( ; ; ) 637 { p = skipspace(p - 1, -1); 638 switch ( *p ) 639 { 640 case ']': /* skip array dimension(s) */ 641 case ')': /* skip procedure args OR name */ 642 { int level = 1; 643 while ( level ) 644 switch ( *--p ) 645 { 646 case ']': case ')': 647 level++; 648 break; 649 case '[': case '(': 650 level--; 651 break; 652 case '/': 653 if (p > buf && p[-1] == '*') 654 p = skipspace(p, -1) + 1; 655 break; 656 case '"': 657 p = scanstring(p, -1) + 1; 658 break; 659 default: ; 660 } 661 } 662 if ( *p == '(' && *skipspace(p + 1, 1) == '*' ) 663 { /* We found the name being declared */ 664 while ( !isidfirstchar(*p) ) 665 p = skipspace(p, 1) + 1; 666 goto found; 667 } 668 break; 669 default: 670 goto found; 671 } 672 } 673 found: if ( *p == '.' && p[-1] == '.' && p[-2] == '.' ) 674 { if ( convert_varargs ) 675 { *bp++ = "va_alist"; 676 vararg = p-2; 677 } 678 else 679 { p++; 680 if ( bp == breaks + 1 ) /* sole argument */ 681 writeblanks(breaks[0], p); 682 else 683 writeblanks(bp[-1] - 1, p); 684 bp--; 685 } 686 } 687 else 688 { while ( isidchar(*p) ) p--; 689 *bp++ = p+1; 690 } 691 p = end; 692 } 693 while ( *p++ == ',' ); 694 *bp = p; 695 /* Make a special check for 'void' arglist */ 696 if ( bp == breaks+2 ) 697 { p = skipspace(breaks[0], 1); 698 if ( !strncmp(p, "void", 4) ) 699 { p = skipspace(p+4, 1); 700 if ( p == breaks[2] - 1 ) 701 { bp = breaks; /* yup, pretend arglist is empty */ 702 writeblanks(breaks[0], p + 1); 703 } 704 } 705 } 706 /* Put out the function name and left parenthesis. */ 707 p = buf; 708 while ( p != endfn ) putc(*p, out), p++; 709 /* Put out the declaration. */ 710 if ( header ) 711 { fputs(");", out); 712 for ( p = breaks[0]; *p; p++ ) 713 if ( *p == '\r' || *p == '\n' ) 714 putc(*p, out); 715 } 716 else 717 { for ( ap = breaks+1; ap < bp; ap += 2 ) 718 { p = *ap; 719 while ( isidchar(*p) ) 720 putc(*p, out), p++; 721 if ( ap < bp - 1 ) 722 fputs(", ", out); 723 } 724 fputs(") ", out); 725 /* Put out the argument declarations */ 726 for ( ap = breaks+2; ap <= bp; ap += 2 ) 727 (*ap)[-1] = ';'; 728 if ( vararg != 0 ) 729 { *vararg = 0; 730 fputs(breaks[0], out); /* any prior args */ 731 fputs("va_dcl", out); /* the final arg */ 732 fputs(bp[0], out); 733 } 734 else 735 fputs(breaks[0], out); 736 } 737 free((char *)breaks); 738 return 0; 739 } 740
