1 /* $NetBSD: ansi2knr.c,v 1.2 2016/01/10 22:16:40 christos Exp $ */
2
3 /* Copyright (C) 1989, 1997, 1998, 1999 Aladdin Enterprises. All rights reserved. */
4
5 /*Id: ansi2knr.c,v 1.1 2000/01/21 00:54:15 alainm Exp */
6 /* Convert ANSI C function definitions to K&R ("traditional C") syntax */
7
8 /*
9 ansi2knr is distributed in the hope that it will be useful, but WITHOUT ANY
10 WARRANTY. No author or distributor accepts responsibility to anyone for the
11 consequences of using it or for whether it serves any particular purpose or
12 works at all, unless he says so in writing. Refer to the GNU General Public
13 License (the "GPL") for full details.
14
15 Everyone is granted permission to copy, modify and redistribute ansi2knr,
16 but only under the conditions described in the GPL. A copy of this license
17 is supposed to have been given to you along with ansi2knr so you can know
18 your rights and responsibilities. It should be in a file named COPYLEFT,
19 or, if there is no file named COPYLEFT, a file named COPYING. Among other
20 things, the copyright notice and this notice must be preserved on all
21 copies.
22
23 We explicitly state here what we believe is already implied by the GPL: if
24 the ansi2knr program is distributed as a separate set of sources and a
25 separate executable file which are aggregated on a storage medium together
26 with another program, this in itself does not bring the other program under
27 the GPL, nor does the mere fact that such a program or the procedures for
28 constructing it invoke the ansi2knr executable bring any other part of the
29 program under the GPL.
30 */
31
32 /*
33 * Usage:
34 ansi2knr [--filename FILENAME] [INPUT_FILE [OUTPUT_FILE]]
35 * --filename provides the file name for the #line directive in the output,
36 * overriding input_file (if present).
37 * If no input_file is supplied, input is read from stdin.
38 * If no output_file is supplied, output goes to stdout.
39 * There are no error messages.
40 *
41 * ansi2knr recognizes function definitions by seeing a non-keyword
42 * identifier at the left margin, followed by a left parenthesis,
43 * with a right parenthesis as the last character on the line,
44 * and with a left brace as the first token on the following line
45 * (ignoring possible intervening comments), except that a line
46 * consisting of only
47 * identifier1(identifier2)
48 * will not be considered a function definition unless identifier2 is
49 * the word "void", and a line consisting of
50 * identifier1(identifier2, <<arbitrary>>)
51 * will not be considered a function definition.
52 * ansi2knr will recognize a multi-line header provided
53 * that no intervening line ends with a left or right brace or a semicolon.
54 * These algorithms ignore whitespace and comments, except that
55 * the function name must be the first thing on the line.
56 * The following constructs will confuse it:
57 * - Any other construct that starts at the left margin and
58 * follows the above syntax (such as a macro or function call).
59 * - Some macros that tinker with the syntax of function headers.
60 */
61
62 /*
63 * The original and principal author of ansi2knr is L. Peter Deutsch
64 * <ghost@aladdin.com>. Other authors are noted in the change history
65 * that follows (in reverse chronological order):
66 lpd 1999-04-12 added minor fixes from Pavel Roskin
67 <pavel_roskin@geocities.com> for clean compilation with
68 gcc -W -Wall
69 lpd 1999-03-22 added hack to recognize lines consisting of
70 identifier1(identifier2, xxx) as *not* being procedures
71 lpd 1999-02-03 made indentation of preprocessor commands consistent
72 lpd 1999-01-28 fixed two bugs: a '/' in an argument list caused an
73 endless loop; quoted strings within an argument list
74 confused the parser
75 lpd 1999-01-24 added a check for write errors on the output,
76 suggested by Jim Meyering <meyering@ascend.com>
77 lpd 1998-11-09 added further hack to recognize identifier(void)
78 as being a procedure
79 lpd 1998-10-23 added hack to recognize lines consisting of
80 identifier1(identifier2) as *not* being procedures
81 lpd 1997-12-08 made input_file optional; only closes input and/or
82 output file if not stdin or stdout respectively; prints
83 usage message on stderr rather than stdout; adds
84 --filename switch (changes suggested by
85 <ceder@lysator.liu.se>)
86 lpd 1996-01-21 added code to cope with not HAVE_CONFIG_H and with
87 compilers that don't understand void, as suggested by
88 Tom Lane
89 lpd 1996-01-15 changed to require that the first non-comment token
90 on the line following a function header be a left brace,
91 to reduce sensitivity to macros, as suggested by Tom Lane
92 <tgl@sss.pgh.pa.us>
93 lpd 1995-06-22 removed #ifndefs whose sole purpose was to define
94 undefined preprocessor symbols as 0; changed all #ifdefs
95 for configuration symbols to #ifs
96 lpd 1995-04-05 changed copyright notice to make it clear that
97 including ansi2knr in a program does not bring the entire
98 program under the GPL
99 lpd 1994-12-18 added conditionals for systems where ctype macros
100 don't handle 8-bit characters properly, suggested by
101 Francois Pinard <pinard@iro.umontreal.ca>;
102 removed --varargs switch (this is now the default)
103 lpd 1994-10-10 removed CONFIG_BROKETS conditional
104 lpd 1994-07-16 added some conditionals to help GNU `configure',
105 suggested by Francois Pinard <pinard@iro.umontreal.ca>;
106 properly erase prototype args in function parameters,
107 contributed by Jim Avera <jima@netcom.com>;
108 correct error in writeblanks (it shouldn't erase EOLs)
109 lpd 1989-xx-xx original version
110 */
111
112 /* Most of the conditionals here are to make ansi2knr work with */
113 /* or without the GNU configure machinery. */
114
115 #if HAVE_CONFIG_H
116 # include <config.h>
117 #endif
118
119 #include <stdio.h>
120 #include <ctype.h>
121
122 #if HAVE_CONFIG_H
123
124 /*
125 For properly autoconfiguring ansi2knr, use AC_CONFIG_HEADER(config.h).
126 This will define HAVE_CONFIG_H and so, activate the following lines.
127 */
128
129 # if STDC_HEADERS || HAVE_STRING_H
130 # include <string.h>
131 # else
132 # include <strings.h>
133 # endif
134
135 #else /* not HAVE_CONFIG_H */
136
137 /* Otherwise do it the hard way */
138
139 # ifdef BSD
140 # include <strings.h>
141 # else
142 # ifdef VMS
143 extern int strlen(), strncmp();
144 # else
145 # include <string.h>
146 # endif
147 # endif
148
149 #endif /* not HAVE_CONFIG_H */
150
151 #if STDC_HEADERS
152 # include <stdlib.h>
153 #else
154 /*
155 malloc and free should be declared in stdlib.h,
156 but if you've got a K&R compiler, they probably aren't.
157 */
158 # ifdef MSDOS
159 # include <malloc.h>
160 # else
161 # ifdef VMS
162 extern char *malloc();
163 extern void free();
164 # else
165 extern char *malloc();
166 extern int free();
167 # endif
168 # endif
169
170 #endif
171
172 /* Define NULL (for *very* old compilers). */
173 #ifndef NULL
174 # define NULL (0)
175 #endif
176
177 /*
178 * The ctype macros don't always handle 8-bit characters correctly.
179 * Compensate for this here.
180 */
181 #ifdef isascii
182 # undef HAVE_ISASCII /* just in case */
183 # define HAVE_ISASCII 1
184 #else
185 #endif
186 #if STDC_HEADERS || !HAVE_ISASCII
187 # define is_ascii(c) 1
188 #else
189 # define is_ascii(c) isascii(c)
190 #endif
191
192 #define is_space(c) (is_ascii(c) && isspace(c))
193 #define is_alpha(c) (is_ascii(c) && isalpha(c))
194 #define is_alnum(c) (is_ascii(c) && isalnum(c))
195
196 /* Scanning macros */
197 #define isidchar(ch) (is_alnum(ch) || (ch) == '_')
198 #define isidfirstchar(ch) (is_alpha(ch) || (ch) == '_')
199
200 /* Forward references */
201 char *skipspace();
202 char *scanstring();
203 int writeblanks();
204 int test1();
205 int convert1();
206
207 /* The main program */
208 int
main(argc,argv)209 main(argc, argv)
210 int argc;
211 char *argv[];
212 { FILE *in = stdin;
213 FILE *out = stdout;
214 char *filename = 0;
215 char *program_name = argv[0];
216 char *output_name = 0;
217 #define bufsize 5000 /* arbitrary size */
218 char *buf;
219 char *line;
220 char *more;
221 char *usage =
222 "Usage: ansi2knr [--filename FILENAME] [INPUT_FILE [OUTPUT_FILE]]\n";
223 /*
224 * In previous versions, ansi2knr recognized a --varargs switch.
225 * If this switch was supplied, ansi2knr would attempt to convert
226 * a ... argument to va_alist and va_dcl; if this switch was not
227 * supplied, ansi2knr would simply drop any such arguments.
228 * Now, ansi2knr always does this conversion, and we only
229 * check for this switch for backward compatibility.
230 */
231 int convert_varargs = 1;
232 int output_error;
233
234 while ( argc > 1 && argv[1][0] == '-' ) {
235 if ( !strcmp(argv[1], "--varargs") ) {
236 convert_varargs = 1;
237 argc--;
238 argv++;
239 continue;
240 }
241 if ( !strcmp(argv[1], "--filename") && argc > 2 ) {
242 filename = argv[2];
243 argc -= 2;
244 argv += 2;
245 continue;
246 }
247 fprintf(stderr, "%s: Unrecognized switch: %s\n", program_name,
248 argv[1]);
249 fprintf(stderr, usage);
250 exit(1);
251 }
252 switch ( argc )
253 {
254 default:
255 fprintf(stderr, usage);
256 exit(0);
257 case 3:
258 output_name = argv[2];
259 out = fopen(output_name, "w");
260 if ( out == NULL ) {
261 fprintf(stderr, "%s: Cannot open output file %s\n",
262 program_name, output_name);
263 exit(1);
264 }
265 /* falls through */
266 case 2:
267 in = fopen(argv[1], "r");
268 if ( in == NULL ) {
269 fprintf(stderr, "%s: Cannot open input file %s\n",
270 program_name, argv[1]);
271 exit(1);
272 }
273 if ( filename == 0 )
274 filename = argv[1];
275 /* falls through */
276 case 1:
277 break;
278 }
279 if ( filename )
280 fprintf(out, "#line 1 \"%s\"\n", filename);
281 buf = malloc(bufsize);
282 if ( buf == NULL )
283 {
284 fprintf(stderr, "Unable to allocate read buffer!\n");
285 exit(1);
286 }
287 line = buf;
288 while ( fgets(line, (unsigned)(buf + bufsize - line), in) != NULL )
289 {
290 test: line += strlen(line);
291 switch ( test1(buf) )
292 {
293 case 2: /* a function header */
294 convert1(buf, out, 1, convert_varargs);
295 break;
296 case 1: /* a function */
297 /* Check for a { at the start of the next line. */
298 more = ++line;
299 f: if ( line >= buf + (bufsize - 1) ) /* overflow check */
300 goto wl;
301 if ( fgets(line, (unsigned)(buf + bufsize - line), in) == NULL )
302 goto wl;
303 switch ( *skipspace(more, 1) )
304 {
305 case '{':
306 /* Definitely a function header. */
307 convert1(buf, out, 0, convert_varargs);
308 fputs(more, out);
309 break;
310 case 0:
311 /* The next line was blank or a comment: */
312 /* keep scanning for a non-comment. */
313 line += strlen(line);
314 goto f;
315 default:
316 /* buf isn't a function header, but */
317 /* more might be. */
318 fputs(buf, out);
319 strcpy(buf, more);
320 line = buf;
321 goto test;
322 }
323 break;
324 case -1: /* maybe the start of a function */
325 if ( line != buf + (bufsize - 1) ) /* overflow check */
326 continue;
327 /* falls through */
328 default: /* not a function */
329 wl: fputs(buf, out);
330 break;
331 }
332 line = buf;
333 }
334 if ( line != buf )
335 fputs(buf, out);
336 free(buf);
337 if ( output_name ) {
338 output_error = ferror(out);
339 output_error |= fclose(out);
340 } else { /* out == stdout */
341 fflush(out);
342 output_error = ferror(out);
343 }
344 if ( output_error ) {
345 fprintf(stderr, "%s: error writing to %s\n", program_name,
346 (output_name ? output_name : "stdout"));
347 exit(1);
348 }
349 if ( in != stdin )
350 fclose(in);
351 return 0;
352 }
353
354 /* Skip over whitespace and comments, in either direction. */
355 char *
skipspace(p,dir)356 skipspace(p, dir)
357 register char *p;
358 register int dir; /* 1 for forward, -1 for backward */
359 { for ( ; ; )
360 { while ( is_space(*p) )
361 p += dir;
362 if ( !(*p == '/' && p[dir] == '*') )
363 break;
364 p += dir; p += dir;
365 while ( !(*p == '*' && p[dir] == '/') )
366 { if ( *p == 0 )
367 return p; /* multi-line comment?? */
368 p += dir;
369 }
370 p += dir; p += dir;
371 }
372 return p;
373 }
374
375 /* Scan over a quoted string, in either direction. */
376 char *
scanstring(p,dir)377 scanstring(p, dir)
378 register char *p;
379 register int dir;
380 {
381 for (p += dir; ; p += dir)
382 if (*p == '"' && p[-dir] != '\\')
383 return p + dir;
384 }
385
386 /*
387 * Write blanks over part of a string.
388 * Don't overwrite end-of-line characters.
389 */
390 int
writeblanks(start,end)391 writeblanks(start, end)
392 char *start;
393 char *end;
394 { char *p;
395 for ( p = start; p < end; p++ )
396 if ( *p != '\r' && *p != '\n' )
397 *p = ' ';
398 return 0;
399 }
400
401 /*
402 * Test whether the string in buf is a function definition.
403 * The string may contain and/or end with a newline.
404 * Return as follows:
405 * 0 - definitely not a function definition;
406 * 1 - definitely a function definition;
407 * 2 - definitely a function prototype (NOT USED);
408 * -1 - may be the beginning of a function definition,
409 * append another line and look again.
410 * The reason we don't attempt to convert function prototypes is that
411 * Ghostscript's declaration-generating macros look too much like
412 * prototypes, and confuse the algorithms.
413 */
414 int
test1(buf)415 test1(buf)
416 char *buf;
417 { register char *p = buf;
418 char *bend;
419 char *endfn;
420 int contin;
421
422 if ( !isidfirstchar(*p) )
423 return 0; /* no name at left margin */
424 bend = skipspace(buf + strlen(buf) - 1, -1);
425 switch ( *bend )
426 {
427 case ';': contin = 0 /*2*/; break;
428 case ')': contin = 1; break;
429 case '{': return 0; /* not a function */
430 case '}': return 0; /* not a function */
431 default: contin = -1;
432 }
433 while ( isidchar(*p) )
434 p++;
435 endfn = p;
436 p = skipspace(p, 1);
437 if ( *p++ != '(' )
438 return 0; /* not a function */
439 p = skipspace(p, 1);
440 if ( *p == ')' )
441 return 0; /* no parameters */
442 /* Check that the apparent function name isn't a keyword. */
443 /* We only need to check for keywords that could be followed */
444 /* by a left parenthesis (which, unfortunately, is most of them). */
445 { static char *words[] =
446 { "asm", "auto", "case", "char", "const", "double",
447 "extern", "float", "for", "if", "int", "long",
448 "register", "return", "short", "signed", "sizeof",
449 "static", "switch", "typedef", "unsigned",
450 "void", "volatile", "while", 0
451 };
452 char **key = words;
453 char *kp;
454 unsigned len = endfn - buf;
455
456 while ( (kp = *key) != 0 )
457 { if ( strlen(kp) == len && !strncmp(kp, buf, len) )
458 return 0; /* name is a keyword */
459 key++;
460 }
461 }
462 {
463 char *id = p;
464 ptrdiff_t len;
465 /*
466 * Check for identifier1(identifier2) and not
467 * identifier1(void), or identifier1(identifier2, xxxx).
468 */
469
470 while ( isidchar(*p) )
471 p++;
472 len = p - id;
473 p = skipspace(p, 1);
474 if (*p == ',' ||
475 (*p == ')' && (len != 4 || strncmp(id, "void", 4)))
476 )
477 return 0; /* not a function */
478 }
479 /*
480 * If the last significant character was a ), we need to count
481 * parentheses, because it might be part of a formal parameter
482 * that is a procedure.
483 */
484 if (contin > 0) {
485 int level = 0;
486
487 for (p = skipspace(buf, 1); *p; p = skipspace(p + 1, 1))
488 level += (*p == '(' ? 1 : *p == ')' ? -1 : 0);
489 if (level > 0)
490 contin = -1;
491 }
492 return contin;
493 }
494
495 /* Convert a recognized function definition or header to K&R syntax. */
496 int
convert1(buf,out,header,convert_varargs)497 convert1(buf, out, header, convert_varargs)
498 char *buf;
499 FILE *out;
500 int header; /* Boolean */
501 int convert_varargs; /* Boolean */
502 { char *endfn;
503 register char *p;
504 /*
505 * The breaks table contains pointers to the beginning and end
506 * of each argument.
507 */
508 char **breaks;
509 unsigned num_breaks = 2; /* for testing */
510 char **btop;
511 char **bp;
512 char **ap;
513 char *vararg = 0;
514
515 /* Pre-ANSI implementations don't agree on whether strchr */
516 /* is called strchr or index, so we open-code it here. */
517 for ( endfn = buf; *(endfn++) != '('; )
518 ;
519 top: p = endfn;
520 breaks = (char **)malloc(sizeof(char *) * num_breaks * 2);
521 if ( breaks == NULL )
522 { /* Couldn't allocate break table, give up */
523 fprintf(stderr, "Unable to allocate break table!\n");
524 fputs(buf, out);
525 return -1;
526 }
527 btop = breaks + num_breaks * 2 - 2;
528 bp = breaks;
529 /* Parse the argument list */
530 do
531 { int level = 0;
532 char *lp = NULL;
533 char *rp = NULL;
534 char *end = NULL;
535
536 if ( bp >= btop )
537 { /* Filled up break table. */
538 /* Allocate a bigger one and start over. */
539 free((char *)breaks);
540 num_breaks <<= 1;
541 goto top;
542 }
543 *bp++ = p;
544 /* Find the end of the argument */
545 for ( ; end == NULL; p++ )
546 { switch(*p)
547 {
548 case ',':
549 if ( !level ) end = p;
550 break;
551 case '(':
552 if ( !level ) lp = p;
553 level++;
554 break;
555 case ')':
556 if ( --level < 0 ) end = p;
557 else rp = p;
558 break;
559 case '/':
560 if (p[1] == '*')
561 p = skipspace(p, 1) - 1;
562 break;
563 case '"':
564 p = scanstring(p, 1) - 1;
565 break;
566 default:
567 ;
568 }
569 }
570 /* Erase any embedded prototype parameters. */
571 if ( lp && rp )
572 writeblanks(lp + 1, rp);
573 p--; /* back up over terminator */
574 /* Find the name being declared. */
575 /* This is complicated because of procedure and */
576 /* array modifiers. */
577 for ( ; ; )
578 { p = skipspace(p - 1, -1);
579 switch ( *p )
580 {
581 case ']': /* skip array dimension(s) */
582 case ')': /* skip procedure args OR name */
583 { int level = 1;
584 while ( level )
585 switch ( *--p )
586 {
587 case ']': case ')':
588 level++;
589 break;
590 case '[': case '(':
591 level--;
592 break;
593 case '/':
594 if (p > buf && p[-1] == '*')
595 p = skipspace(p, -1) + 1;
596 break;
597 case '"':
598 p = scanstring(p, -1) + 1;
599 break;
600 default: ;
601 }
602 }
603 if ( *p == '(' && *skipspace(p + 1, 1) == '*' )
604 { /* We found the name being declared */
605 while ( !isidfirstchar(*p) )
606 p = skipspace(p, 1) + 1;
607 goto found;
608 }
609 break;
610 default:
611 goto found;
612 }
613 }
614 found: if ( *p == '.' && p[-1] == '.' && p[-2] == '.' )
615 { if ( convert_varargs )
616 { *bp++ = "va_alist";
617 vararg = p-2;
618 }
619 else
620 { p++;
621 if ( bp == breaks + 1 ) /* sole argument */
622 writeblanks(breaks[0], p);
623 else
624 writeblanks(bp[-1] - 1, p);
625 bp--;
626 }
627 }
628 else
629 { while ( isidchar(*p) ) p--;
630 *bp++ = p+1;
631 }
632 p = end;
633 }
634 while ( *p++ == ',' );
635 *bp = p;
636 /* Make a special check for 'void' arglist */
637 if ( bp == breaks+2 )
638 { p = skipspace(breaks[0], 1);
639 if ( !strncmp(p, "void", 4) )
640 { p = skipspace(p+4, 1);
641 if ( p == breaks[2] - 1 )
642 { bp = breaks; /* yup, pretend arglist is empty */
643 writeblanks(breaks[0], p + 1);
644 }
645 }
646 }
647 /* Put out the function name and left parenthesis. */
648 p = buf;
649 while ( p != endfn ) putc(*p, out), p++;
650 /* Put out the declaration. */
651 if ( header )
652 { fputs(");", out);
653 for ( p = breaks[0]; *p; p++ )
654 if ( *p == '\r' || *p == '\n' )
655 putc(*p, out);
656 }
657 else
658 { for ( ap = breaks+1; ap < bp; ap += 2 )
659 { p = *ap;
660 while ( isidchar(*p) )
661 putc(*p, out), p++;
662 if ( ap < bp - 1 )
663 fputs(", ", out);
664 }
665 fputs(") ", out);
666 /* Put out the argument declarations */
667 for ( ap = breaks+2; ap <= bp; ap += 2 )
668 (*ap)[-1] = ';';
669 if ( vararg != 0 )
670 { *vararg = 0;
671 fputs(breaks[0], out); /* any prior args */
672 fputs("va_dcl", out); /* the final arg */
673 fputs(bp[0], out);
674 }
675 else
676 fputs(breaks[0], out);
677 }
678 free((char *)breaks);
679 return 0;
680 }
681