1 /* $NetBSD: ansi2knr.c,v 1.2 2003/12/04 16:23:38 drochner Exp $ */
3 /* Copyright (C) 1989, 2000 Aladdin Enterprises. All rights reserved. */
5 /*Id: ansi2knr.c,v 1.3 2000/04/13 03:41:48 lpd Exp*/
6 /* Convert ANSI C function definitions to K&R ("traditional C") syntax */
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.
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
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.
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.
41 * ansi2knr recognizes function definitions by seeing a non-keyword
42 * identifier at the left margin, followed by a left parenthesis, with a
43 * right parenthesis as the last character on the line, and with a left
44 * brace as the first token on the following line (ignoring possible
45 * intervening comments and/or preprocessor directives), except that a line
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 that no intervening
53 * line ends with a left or right brace or a semicolon. These algorithms
54 * ignore whitespace, comments, and preprocessor directives, except that
55 * the function name must be the first thing on the line. The following
56 * 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.
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):
67 lpd 2000-04-12 backs out Eggert's changes because of bugs:
68 - concatlits didn't declare the type of its bufend argument;
69 - concatlits didn't recognize when it was inside a comment;
70 - scanstring could scan backward past the beginning of the string; when
71 - the check for \ + newline in scanstring was unnecessary.
73 2000-03-05 Paul Eggert <eggert@twinsun.com>
75 Add support for concatenated string literals.
76 * ansi2knr.c (concatlits): New decl.
77 (main): Invoke concatlits to concatenate string literals.
78 (scanstring): Handle backslash-newline correctly. Work with
79 character constants. Fix bug when scanning backwards through
80 backslash-quote. Check for unterminated strings.
81 (convert1): Parse character constants, too.
82 (appendline, concatlits): New functions.
83 * ansi2knr.1: Document this.
85 lpd 1999-08-17 added code to allow preprocessor directives
86 wherever comments are allowed
87 lpd 1999-04-12 added minor fixes from Pavel Roskin
88 <pavel_roskin@geocities.com> for clean compilation with
90 lpd 1999-03-22 added hack to recognize lines consisting of
91 identifier1(identifier2, xxx) as *not* being procedures
92 lpd 1999-02-03 made indentation of preprocessor commands consistent
93 lpd 1999-01-28 fixed two bugs: a '/' in an argument list caused an
94 endless loop; quoted strings within an argument list
96 lpd 1999-01-24 added a check for write errors on the output,
97 suggested by Jim Meyering <meyering@ascend.com>
98 lpd 1998-11-09 added further hack to recognize identifier(void)
100 lpd 1998-10-23 added hack to recognize lines consisting of
101 identifier1(identifier2) as *not* being procedures
102 lpd 1997-12-08 made input_file optional; only closes input and/or
103 output file if not stdin or stdout respectively; prints
104 usage message on stderr rather than stdout; adds
105 --filename switch (changes suggested by
106 <ceder@lysator.liu.se>)
107 lpd 1996-01-21 added code to cope with not HAVE_CONFIG_H and with
108 compilers that don't understand void, as suggested by
110 lpd 1996-01-15 changed to require that the first non-comment token
111 on the line following a function header be a left brace,
112 to reduce sensitivity to macros, as suggested by Tom Lane
114 lpd 1995-06-22 removed #ifndefs whose sole purpose was to define
115 undefined preprocessor symbols as 0; changed all #ifdefs
116 for configuration symbols to #ifs
117 lpd 1995-04-05 changed copyright notice to make it clear that
118 including ansi2knr in a program does not bring the entire
119 program under the GPL
120 lpd 1994-12-18 added conditionals for systems where ctype macros
121 don't handle 8-bit characters properly, suggested by
122 Francois Pinard <pinard@iro.umontreal.ca>;
123 removed --varargs switch (this is now the default)
124 lpd 1994-10-10 removed CONFIG_BROKETS conditional
125 lpd 1994-07-16 added some conditionals to help GNU `configure',
126 suggested by Francois Pinard <pinard@iro.umontreal.ca>;
127 properly erase prototype args in function parameters,
128 contributed by Jim Avera <jima@netcom.com>;
129 correct error in writeblanks (it shouldn't erase EOLs)
130 lpd 1989-xx-xx original version
133 /* Most of the conditionals here are to make ansi2knr work with */
134 /* or without the GNU configure machinery. */
146 For properly autoconfiguring ansi2knr, use AC_CONFIG_HEADER(config.h).
147 This will define HAVE_CONFIG_H and so, activate the following lines.
150 # if STDC_HEADERS || HAVE_STRING_H
153 # include <strings.h>
156 #else /* not HAVE_CONFIG_H */
158 /* Otherwise do it the hard way */
161 # include <strings.h>
164 extern int strlen(), strncmp();
170 #endif /* not HAVE_CONFIG_H */
176 malloc and free should be declared in stdlib.h,
177 but if you've got a K&R compiler, they probably aren't.
183 extern char *malloc();
186 extern char *malloc();
193 /* Define NULL (for *very* old compilers). */
199 * The ctype macros don't always handle 8-bit characters correctly.
200 * Compensate for this here.
203 # undef HAVE_ISASCII /* just in case */
204 # define HAVE_ISASCII 1
207 #if STDC_HEADERS || !HAVE_ISASCII
208 # define is_ascii(c) 1
210 # define is_ascii(c) isascii(c)
213 #define is_space(c) (is_ascii(c) && isspace(c))
214 #define is_alpha(c) (is_ascii(c) && isalpha(c))
215 #define is_alnum(c) (is_ascii(c) && isalnum(c))
217 /* Scanning macros */
218 #define isidchar(ch) (is_alnum(ch) || (ch) == '_')
219 #define isidfirstchar(ch) (is_alpha(ch) || (ch) == '_')
221 /* Forward references */
222 char *ppdirforward();
223 char *ppdirbackward();
230 /* The main program */
238 char *program_name
= argv
[0];
239 char *output_name
= 0;
240 #define bufsize 5000 /* arbitrary size */
245 "Usage: ansi2knr [--filename FILENAME] [INPUT_FILE [OUTPUT_FILE]]\n";
247 * In previous versions, ansi2knr recognized a --varargs switch.
248 * If this switch was supplied, ansi2knr would attempt to convert
249 * a ... argument to va_alist and va_dcl; if this switch was not
250 * supplied, ansi2knr would simply drop any such arguments.
251 * Now, ansi2knr always does this conversion, and we only
252 * check for this switch for backward compatibility.
254 int convert_varargs
= 1;
257 while ( argc
> 1 && argv
[1][0] == '-' ) {
258 if ( !strcmp(argv
[1], "--varargs") ) {
264 if ( !strcmp(argv
[1], "--filename") && argc
> 2 ) {
270 fprintf(stderr
, "%s: Unrecognized switch: %s\n", program_name
,
272 fprintf(stderr
, usage
);
278 fprintf(stderr
, usage
);
281 output_name
= argv
[2];
282 out
= fopen(output_name
, "w");
284 fprintf(stderr
, "%s: Cannot open output file %s\n",
285 program_name
, output_name
);
290 in
= fopen(argv
[1], "r");
292 fprintf(stderr
, "%s: Cannot open input file %s\n",
293 program_name
, argv
[1]);
303 fprintf(out
, "#line 1 \"%s\"\n", filename
);
304 buf
= malloc(bufsize
);
307 fprintf(stderr
, "Unable to allocate read buffer!\n");
311 while ( fgets(line
, (unsigned)(buf
+ bufsize
- line
), in
) != NULL
)
313 test
: line
+= strlen(line
);
314 switch ( test1(buf
) )
316 case 2: /* a function header */
317 convert1(buf
, out
, 1, convert_varargs
);
319 case 1: /* a function */
320 /* Check for a { at the start of the next line. */
322 f
: if ( line
>= buf
+ (bufsize
- 1) ) /* overflow check */
324 if ( fgets(line
, (unsigned)(buf
+ bufsize
- line
), in
) == NULL
)
326 switch ( *skipspace(ppdirforward(more
), 1) )
329 /* Definitely a function header. */
330 convert1(buf
, out
, 0, convert_varargs
);
334 /* The next line was blank or a comment: */
335 /* keep scanning for a non-comment. */
336 line
+= strlen(line
);
339 /* buf isn't a function header, but */
347 case -1: /* maybe the start of a function */
348 if ( line
!= buf
+ (bufsize
- 1) ) /* overflow check */
351 default: /* not a function */
361 output_error
= ferror(out
);
362 output_error
|= fclose(out
);
363 } else { /* out == stdout */
365 output_error
= ferror(out
);
367 if ( output_error
) {
368 fprintf(stderr
, "%s: error writing to %s\n", program_name
,
369 (output_name
? output_name
: "stdout"));
378 * Skip forward or backward over one or more preprocessor directives.
384 for (; *p
== '#'; ++p
) {
385 for (; *p
!= '\r' && *p
!= '\n'; ++p
)
388 if (*p
== '\r' && p
[1] == '\n')
394 ppdirbackward(p
, limit
)
401 if (*np
== '\n' && np
[-1] == '\r')
403 for (; np
> limit
&& np
[-1] != '\r' && np
[-1] != '\n'; --np
)
412 * Skip over whitespace, comments, and preprocessor directives,
413 * in either direction.
418 int dir
; /* 1 for forward, -1 for backward */
421 while ( is_space(*p
) )
423 if ( !(*p
== '/' && p
[dir
] == '*') )
426 while ( !(*p
== '*' && p
[dir
] == '/') ) {
428 return p
; /* multi-line comment?? */
436 /* Scan over a quoted string, in either direction. */
442 for (p
+= dir
; ; p
+= dir
)
443 if (*p
== '"' && p
[-dir
] != '\\')
448 * Write blanks over part of a string.
449 * Don't overwrite end-of-line characters.
452 writeblanks(start
, end
)
456 for ( p
= start
; p
< end
; p
++ )
457 if ( *p
!= '\r' && *p
!= '\n' )
463 * Test whether the string in buf is a function definition.
464 * The string may contain and/or end with a newline.
466 * 0 - definitely not a function definition;
467 * 1 - definitely a function definition;
468 * 2 - definitely a function prototype (NOT USED);
469 * -1 - may be the beginning of a function definition,
470 * append another line and look again.
471 * The reason we don't attempt to convert function prototypes is that
472 * Ghostscript's declaration-generating macros look too much like
473 * prototypes, and confuse the algorithms.
483 if ( !isidfirstchar(*p
) )
484 return 0; /* no name at left margin */
485 bend
= skipspace(ppdirbackward(buf
+ strlen(buf
) - 1, buf
), -1);
488 case ';': contin
= 0 /*2*/; break;
489 case ')': contin
= 1; break;
490 case '{': return 0; /* not a function */
491 case '}': return 0; /* not a function */
492 default: contin
= -1;
494 while ( isidchar(*p
) )
499 return 0; /* not a function */
502 return 0; /* no parameters */
503 /* Check that the apparent function name isn't a keyword. */
504 /* We only need to check for keywords that could be followed */
505 /* by a left parenthesis (which, unfortunately, is most of them). */
506 { static char *words
[] =
507 { "asm", "auto", "case", "char", "const", "double",
508 "extern", "float", "for", "if", "int", "long",
509 "register", "return", "short", "signed", "sizeof",
510 "static", "switch", "typedef", "unsigned",
511 "void", "volatile", "while", 0
515 unsigned len
= endfn
- buf
;
517 while ( (kp
= *key
) != 0 )
518 { if ( strlen(kp
) == len
&& !strncmp(kp
, buf
, len
) )
519 return 0; /* name is a keyword */
527 * Check for identifier1(identifier2) and not
528 * identifier1(void), or identifier1(identifier2, xxxx).
531 while ( isidchar(*p
) )
536 (*p
== ')' && (len
!= 4 || strncmp(id
, "void", 4)))
538 return 0; /* not a function */
541 * If the last significant character was a ), we need to count
542 * parentheses, because it might be part of a formal parameter
543 * that is a procedure.
548 for (p
= skipspace(buf
, 1); *p
; p
= skipspace(p
+ 1, 1))
549 level
+= (*p
== '(' ? 1 : *p
== ')' ? -1 : 0);
556 /* Convert a recognized function definition or header to K&R syntax. */
558 convert1(buf
, out
, header
, convert_varargs
)
561 int header
; /* Boolean */
562 int convert_varargs
; /* Boolean */
566 * The breaks table contains pointers to the beginning and end
570 unsigned num_breaks
= 2; /* for testing */
576 /* Pre-ANSI implementations don't agree on whether strchr */
577 /* is called strchr or index, so we open-code it here. */
578 for ( endfn
= buf
; *(endfn
++) != '('; )
581 breaks
= (char **)malloc(sizeof(char *) * num_breaks
* 2);
582 if ( breaks
== NULL
)
583 { /* Couldn't allocate break table, give up */
584 fprintf(stderr
, "Unable to allocate break table!\n");
588 btop
= breaks
+ num_breaks
* 2 - 2;
590 /* Parse the argument list */
598 { /* Filled up break table. */
599 /* Allocate a bigger one and start over. */
600 free((char *)breaks
);
605 /* Find the end of the argument */
606 for ( ; end
== NULL
; p
++ )
610 if ( !level
) end
= p
;
613 if ( !level
) lp
= p
;
617 if ( --level
< 0 ) end
= p
;
622 p
= skipspace(p
, 1) - 1;
625 p
= scanstring(p
, 1) - 1;
631 /* Erase any embedded prototype parameters. */
633 writeblanks(lp
+ 1, rp
);
634 p
--; /* back up over terminator */
635 /* Find the name being declared. */
636 /* This is complicated because of procedure and */
637 /* array modifiers. */
639 { p
= skipspace(p
- 1, -1);
642 case ']': /* skip array dimension(s) */
643 case ')': /* skip procedure args OR name */
655 if (p
> buf
&& p
[-1] == '*')
656 p
= skipspace(p
, -1) + 1;
659 p
= scanstring(p
, -1) + 1;
664 if ( *p
== '(' && *skipspace(p
+ 1, 1) == '*' )
665 { /* We found the name being declared */
666 while ( !isidfirstchar(*p
) )
667 p
= skipspace(p
, 1) + 1;
675 found
: if ( *p
== '.' && p
[-1] == '.' && p
[-2] == '.' )
676 { if ( convert_varargs
)
677 { *bp
++ = "va_alist";
682 if ( bp
== breaks
+ 1 ) /* sole argument */
683 writeblanks(breaks
[0], p
);
685 writeblanks(bp
[-1] - 1, p
);
690 { while ( isidchar(*p
) ) p
--;
695 while ( *p
++ == ',' );
697 /* Make a special check for 'void' arglist */
698 if ( bp
== breaks
+2 )
699 { p
= skipspace(breaks
[0], 1);
700 if ( !strncmp(p
, "void", 4) )
701 { p
= skipspace(p
+4, 1);
702 if ( p
== breaks
[2] - 1 )
703 { bp
= breaks
; /* yup, pretend arglist is empty */
704 writeblanks(breaks
[0], p
+ 1);
708 /* Put out the function name and left parenthesis. */
710 while ( p
!= endfn
) putc(*p
, out
), p
++;
711 /* Put out the declaration. */
714 for ( p
= breaks
[0]; *p
; p
++ )
715 if ( *p
== '\r' || *p
== '\n' )
719 { for ( ap
= breaks
+1; ap
< bp
; ap
+= 2 )
721 while ( isidchar(*p
) )
727 /* Put out the argument declarations */
728 for ( ap
= breaks
+2; ap
<= bp
; ap
+= 2 )
732 fputs(breaks
[0], out
); /* any prior args */
733 fputs("va_dcl", out
); /* the final arg */
737 fputs(breaks
[0], out
);
739 free((char *)breaks
);