1 /* Part of CPP library. (Macro and #define handling.)
2 Copyright (C) 1986, 1987, 1989, 1992, 1993, 1994, 1995, 1996, 1998,
3 1999, 2000, 2001, 2002 Free Software Foundation, Inc.
4 Written by Per Bothner, 1994.
5 Based on CCCP program by Paul Rubin, June 1986
6 Adapted to ANSI C, Richard Stallman, Jan 1987
8 This program is free software; you can redistribute it and/or modify it
9 under the terms of the GNU General Public License as published by the
10 Free Software Foundation; either version 2, or (at your option) any
13 This program is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
18 You should have received a copy of the GNU General Public License
19 along with this program; if not, write to the Free Software
20 Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
22 In other words, you are welcome to use, share and improve this program.
23 You are forbidden to forbid anyone else to use, share and improve
24 what you give them. Help stamp out software-hoarding! */
31 typedef struct macro_arg macro_arg
;
34 const cpp_token
**first
; /* First token in unexpanded argument. */
35 const cpp_token
**expanded
; /* Macro-expanded argument. */
36 const cpp_token
*stringified
; /* Stringified argument. */
37 unsigned int count
; /* # of tokens in argument. */
38 unsigned int expanded_count
; /* # of tokens in expanded argument. */
41 /* Macro expansion. */
43 static int enter_macro_context
PARAMS ((cpp_reader
*, cpp_hashnode
*));
44 static int builtin_macro
PARAMS ((cpp_reader
*, cpp_hashnode
*));
45 static void push_token_context
46 PARAMS ((cpp_reader
*, cpp_hashnode
*, const cpp_token
*, unsigned int));
47 static void push_ptoken_context
48 PARAMS ((cpp_reader
*, cpp_hashnode
*, _cpp_buff
*,
49 const cpp_token
**, unsigned int));
50 static _cpp_buff
*collect_args
PARAMS ((cpp_reader
*, const cpp_hashnode
*));
51 static cpp_context
*next_context
PARAMS ((cpp_reader
*));
52 static const cpp_token
*padding_token
53 PARAMS ((cpp_reader
*, const cpp_token
*));
54 static void expand_arg
PARAMS ((cpp_reader
*, macro_arg
*));
55 static const cpp_token
*new_string_token
PARAMS ((cpp_reader
*, uchar
*,
57 static const cpp_token
*new_number_token
PARAMS ((cpp_reader
*, unsigned int));
58 static const cpp_token
*stringify_arg
PARAMS ((cpp_reader
*, macro_arg
*));
59 static void paste_all_tokens
PARAMS ((cpp_reader
*, const cpp_token
*));
60 static bool paste_tokens
PARAMS ((cpp_reader
*, const cpp_token
**,
62 static void replace_args
PARAMS ((cpp_reader
*, cpp_hashnode
*, cpp_macro
*,
64 static _cpp_buff
*funlike_invocation_p
PARAMS ((cpp_reader
*, cpp_hashnode
*));
66 /* #define directive parsing and handling. */
68 static cpp_token
*alloc_expansion_token
PARAMS ((cpp_reader
*, cpp_macro
*));
69 static cpp_token
*lex_expansion_token
PARAMS ((cpp_reader
*, cpp_macro
*));
70 static int warn_of_redefinition
PARAMS ((const cpp_hashnode
*,
72 static int save_parameter
PARAMS ((cpp_reader
*, cpp_macro
*, cpp_hashnode
*));
73 static int parse_params
PARAMS ((cpp_reader
*, cpp_macro
*));
74 static void check_trad_stringification
PARAMS ((cpp_reader
*,
78 /* Allocates and returns a CPP_STRING token, containing TEXT of length
79 LEN, after null-terminating it. TEXT must be in permanent storage. */
80 static const cpp_token
*
81 new_string_token (pfile
, text
, len
)
86 cpp_token
*token
= _cpp_temp_token (pfile
);
89 token
->type
= CPP_STRING
;
90 token
->val
.str
.len
= len
;
91 token
->val
.str
.text
= text
;
96 /* Allocates and returns a CPP_NUMBER token evaluating to NUMBER. */
97 static const cpp_token
*
98 new_number_token (pfile
, number
)
102 cpp_token
*token
= _cpp_temp_token (pfile
);
103 /* 21 bytes holds all NUL-terminated unsigned 64-bit numbers. */
104 unsigned char *buf
= _cpp_unaligned_alloc (pfile
, 21);
106 sprintf ((char *) buf
, "%u", number
);
107 token
->type
= CPP_NUMBER
;
108 token
->val
.str
.text
= buf
;
109 token
->val
.str
.len
= ustrlen (buf
);
114 static const char * const monthnames
[] =
116 "Jan", "Feb", "Mar", "Apr", "May", "Jun",
117 "Jul", "Aug", "Sep", "Oct", "Nov", "Dec"
120 /* Handle builtin macros like __FILE__, and push the resulting token
121 on the context stack. Also handles _Pragma, for which no new token
122 is created. Returns 1 if it generates a new token context, 0 to
123 return the token to the caller. */
125 builtin_macro (pfile
, node
)
129 const cpp_token
*result
;
131 switch (node
->value
.builtin
)
134 cpp_error (pfile
, DL_ICE
, "invalid built-in macro \"%s\"",
144 const struct line_map
*map
= pfile
->map
;
146 if (node
->value
.builtin
== BT_BASE_FILE
)
147 while (! MAIN_FILE_P (map
))
148 map
= INCLUDED_FROM (&pfile
->line_maps
, map
);
152 buf
= _cpp_unaligned_alloc (pfile
, len
* 4 + 1);
153 len
= cpp_quote_string (buf
, (const unsigned char *) name
, len
) - buf
;
155 result
= new_string_token (pfile
, buf
, len
);
159 case BT_INCLUDE_LEVEL
:
160 /* The line map depth counts the primary source as level 1, but
161 historically __INCLUDE_DEPTH__ has called the primary source
163 result
= new_number_token (pfile
, pfile
->line_maps
.depth
- 1);
167 /* If __LINE__ is embedded in a macro, it must expand to the
168 line of the macro's invocation, not its definition.
169 Otherwise things like assert() will not work properly. */
170 result
= new_number_token (pfile
,
171 SOURCE_LINE (pfile
->map
,
172 pfile
->cur_token
[-1].line
));
175 /* __STDC__ has the value 1 under normal circumstances.
176 However, if (a) we are in a system header, (b) the option
177 stdc_0_in_system_headers is true (set by target config), and
178 (c) we are not in strictly conforming mode, then it has the
183 enum c_lang lang
= CPP_OPTION (pfile
, lang
);
184 if (CPP_IN_SYSTEM_HEADER (pfile
)
185 && CPP_OPTION (pfile
, stdc_0_in_system_headers
)
186 && !(lang
== CLK_STDC89
|| lang
== CLK_STDC94
187 || lang
== CLK_STDC99
)) /* || lang == CLK_CXX98 ? */
192 result
= new_number_token (pfile
, stdc
);
198 if (pfile
->date
.type
== CPP_EOF
)
200 /* Allocate __DATE__ and __TIME__ strings from permanent
201 storage. We only do this once, and don't generate them
202 at init time, because time() and localtime() are very
203 slow on some systems. */
204 time_t tt
= time (NULL
);
205 struct tm
*tb
= localtime (&tt
);
207 pfile
->date
.val
.str
.text
=
208 _cpp_unaligned_alloc (pfile
, sizeof ("Oct 11 1347"));
209 pfile
->date
.val
.str
.len
= sizeof ("Oct 11 1347") - 1;
210 pfile
->date
.type
= CPP_STRING
;
211 pfile
->date
.flags
= 0;
212 sprintf ((char *) pfile
->date
.val
.str
.text
, "%s %2d %4d",
213 monthnames
[tb
->tm_mon
], tb
->tm_mday
, tb
->tm_year
+ 1900);
215 pfile
->time
.val
.str
.text
=
216 _cpp_unaligned_alloc (pfile
, sizeof ("12:34:56"));
217 pfile
->time
.val
.str
.len
= sizeof ("12:34:56") - 1;
218 pfile
->time
.type
= CPP_STRING
;
219 pfile
->time
.flags
= 0;
220 sprintf ((char *) pfile
->time
.val
.str
.text
, "%02d:%02d:%02d",
221 tb
->tm_hour
, tb
->tm_min
, tb
->tm_sec
);
224 if (node
->value
.builtin
== BT_DATE
)
225 result
= &pfile
->date
;
227 result
= &pfile
->time
;
231 /* Don't interpret _Pragma within directives. The standard is
232 not clear on this, but to me this makes most sense. */
233 if (pfile
->state
.in_directive
)
236 _cpp_do__Pragma (pfile
);
240 push_token_context (pfile
, NULL
, result
, 1);
244 /* Copies SRC, of length LEN, to DEST, adding backslashes before all
245 backslashes and double quotes. Non-printable characters are
246 converted to octal. DEST must be of sufficient size. Returns
247 a pointer to the end of the string. */
249 cpp_quote_string (dest
, src
, len
)
258 if (c
== '\\' || c
== '"')
269 sprintf ((char *) dest
, "\\%03o", c
);
278 /* Convert a token sequence ARG to a single string token according to
279 the rules of the ISO C #-operator. */
280 static const cpp_token
*
281 stringify_arg (pfile
, arg
)
285 unsigned char *dest
= BUFF_FRONT (pfile
->u_buff
);
286 unsigned int i
, escape_it
, backslash_count
= 0;
287 const cpp_token
*source
= NULL
;
290 /* Loop, reading in the argument's tokens. */
291 for (i
= 0; i
< arg
->count
; i
++)
293 const cpp_token
*token
= arg
->first
[i
];
295 if (token
->type
== CPP_PADDING
)
298 source
= token
->val
.source
;
302 escape_it
= (token
->type
== CPP_STRING
|| token
->type
== CPP_WSTRING
303 || token
->type
== CPP_CHAR
|| token
->type
== CPP_WCHAR
);
305 /* Room for each char being written in octal, initial space and
307 len
= cpp_token_len (token
);
312 if ((size_t) (BUFF_LIMIT (pfile
->u_buff
) - dest
) < len
)
314 size_t len_so_far
= dest
- BUFF_FRONT (pfile
->u_buff
);
315 _cpp_extend_buff (pfile
, &pfile
->u_buff
, len
);
316 dest
= BUFF_FRONT (pfile
->u_buff
) + len_so_far
;
319 /* Leading white space? */
320 if (dest
!= BUFF_FRONT (pfile
->u_buff
))
324 if (source
->flags
& PREV_WHITE
)
331 _cpp_buff
*buff
= _cpp_get_buff (pfile
, len
);
332 unsigned char *buf
= BUFF_FRONT (buff
);
333 len
= cpp_spell_token (pfile
, token
, buf
) - buf
;
334 dest
= cpp_quote_string (dest
, buf
, len
);
335 _cpp_release_buff (pfile
, buff
);
338 dest
= cpp_spell_token (pfile
, token
, dest
);
340 if (token
->type
== CPP_OTHER
&& token
->val
.c
== '\\')
346 /* Ignore the final \ of invalid string literals. */
347 if (backslash_count
& 1)
349 cpp_error (pfile
, DL_WARNING
,
350 "invalid string literal, ignoring final '\\'");
354 /* Commit the memory, including NUL, and return the token. */
355 len
= dest
- BUFF_FRONT (pfile
->u_buff
);
356 BUFF_FRONT (pfile
->u_buff
) = dest
+ 1;
357 return new_string_token (pfile
, dest
- len
, len
);
360 /* Try to paste two tokens. On success, return non-zero. In any
361 case, PLHS is updated to point to the pasted token, which is
362 guaranteed to not have the PASTE_LEFT flag set. */
364 paste_tokens (pfile
, plhs
, rhs
)
366 const cpp_token
**plhs
, *rhs
;
368 unsigned char *buf
, *end
;
369 const cpp_token
*lhs
;
374 len
= cpp_token_len (lhs
) + cpp_token_len (rhs
) + 1;
375 buf
= (unsigned char *) alloca (len
);
376 end
= cpp_spell_token (pfile
, lhs
, buf
);
378 /* Avoid comment headers, since they are still processed in stage 3.
379 It is simpler to insert a space here, rather than modifying the
380 lexer to ignore comments in some circumstances. Simply returning
381 false doesn't work, since we want to clear the PASTE_LEFT flag. */
382 if (lhs
->type
== CPP_DIV
383 && (rhs
->type
== CPP_MULT
|| rhs
->type
== CPP_DIV
))
385 end
= cpp_spell_token (pfile
, rhs
, end
);
388 cpp_push_buffer (pfile
, buf
, end
- buf
, /* from_stage3 */ true, 1);
390 /* Tweak the column number the lexer will report. */
391 pfile
->buffer
->col_adjust
= pfile
->cur_token
[-1].col
- 1;
393 /* We don't want a leading # to be interpreted as a directive. */
394 pfile
->buffer
->saved_flags
= 0;
396 /* Set pfile->cur_token as required by _cpp_lex_direct. */
397 pfile
->cur_token
= _cpp_temp_token (pfile
);
398 *plhs
= _cpp_lex_direct (pfile
);
399 valid
= pfile
->buffer
->cur
== pfile
->buffer
->rlimit
;
400 _cpp_pop_buffer (pfile
);
405 /* Handles an arbitrarily long sequence of ## operators, with initial
406 operand LHS. This implementation is left-associative,
407 non-recursive, and finishes a paste before handling succeeding
408 ones. If a paste fails, we back up to the RHS of the failing ##
409 operator before pushing the context containing the result of prior
410 successful pastes, with the effect that the RHS appears in the
411 output stream after the pasted LHS normally. */
413 paste_all_tokens (pfile
, lhs
)
415 const cpp_token
*lhs
;
417 const cpp_token
*rhs
;
418 cpp_context
*context
= pfile
->context
;
422 /* Take the token directly from the current context. We can do
423 this, because we are in the replacement list of either an
424 object-like macro, or a function-like macro with arguments
425 inserted. In either case, the constraints to #define
426 guarantee we have at least one more token. */
427 if (context
->direct_p
)
428 rhs
= context
->first
.token
++;
430 rhs
= *context
->first
.ptoken
++;
432 if (rhs
->type
== CPP_PADDING
)
435 if (!paste_tokens (pfile
, &lhs
, rhs
))
437 _cpp_backup_tokens (pfile
, 1);
439 /* Mandatory error for all apart from assembler. */
440 if (CPP_OPTION (pfile
, lang
) != CLK_ASM
)
441 cpp_error (pfile
, DL_ERROR
,
442 "pasting \"%s\" and \"%s\" does not give a valid preprocessing token",
443 cpp_token_as_text (pfile
, lhs
),
444 cpp_token_as_text (pfile
, rhs
));
448 while (rhs
->flags
& PASTE_LEFT
);
450 /* Put the resulting token in its own context. */
451 push_token_context (pfile
, NULL
, lhs
, 1);
454 /* Reads and returns the arguments to a function-like macro
455 invocation. Assumes the opening parenthesis has been processed.
456 If there is an error, emits an appropriate diagnostic and returns
457 NULL. Each argument is terminated by a CPP_EOF token, for the
458 future benefit of expand_arg(). */
460 collect_args (pfile
, node
)
462 const cpp_hashnode
*node
;
464 _cpp_buff
*buff
, *base_buff
;
466 macro_arg
*args
, *arg
;
467 const cpp_token
*token
;
471 macro
= node
->value
.macro
;
473 argc
= macro
->paramc
;
476 buff
= _cpp_get_buff (pfile
, argc
* (50 * sizeof (cpp_token
*)
477 + sizeof (macro_arg
)));
479 args
= (macro_arg
*) buff
->base
;
480 memset (args
, 0, argc
* sizeof (macro_arg
));
481 buff
->cur
= (unsigned char *) &args
[argc
];
482 arg
= args
, argc
= 0;
484 /* Collect the tokens making up each argument. We don't yet know
485 how many arguments have been supplied, whether too many or too
486 few. Hence the slightly bizarre usage of "argc" and "arg". */
489 unsigned int paren_depth
= 0;
490 unsigned int ntokens
= 0;
493 arg
->first
= (const cpp_token
**) buff
->cur
;
497 /* Require space for 2 new tokens (including a CPP_EOF). */
498 if ((unsigned char *) &arg
->first
[ntokens
+ 2] > buff
->limit
)
500 buff
= _cpp_append_extend_buff (pfile
, buff
,
501 1000 * sizeof (cpp_token
*));
502 arg
->first
= (const cpp_token
**) buff
->cur
;
505 token
= cpp_get_token (pfile
);
507 if (token
->type
== CPP_PADDING
)
509 /* Drop leading padding. */
513 else if (token
->type
== CPP_OPEN_PAREN
)
515 else if (token
->type
== CPP_CLOSE_PAREN
)
517 if (paren_depth
-- == 0)
520 else if (token
->type
== CPP_COMMA
)
522 /* A comma does not terminate an argument within
523 parentheses or as part of a variable argument. */
525 && ! (macro
->variadic
&& argc
== macro
->paramc
))
528 else if (token
->type
== CPP_EOF
529 || (token
->type
== CPP_HASH
&& token
->flags
& BOL
))
532 arg
->first
[ntokens
++] = token
;
535 /* Drop trailing padding. */
536 while (ntokens
> 0 && arg
->first
[ntokens
- 1]->type
== CPP_PADDING
)
539 arg
->count
= ntokens
;
540 arg
->first
[ntokens
] = &pfile
->eof
;
542 /* Terminate the argument. Excess arguments loop back and
543 overwrite the final legitimate argument, before failing. */
544 if (argc
<= macro
->paramc
)
546 buff
->cur
= (unsigned char *) &arg
->first
[ntokens
+ 1];
547 if (argc
!= macro
->paramc
)
551 while (token
->type
!= CPP_CLOSE_PAREN
&& token
->type
!= CPP_EOF
);
553 if (token
->type
== CPP_EOF
)
555 /* We still need the CPP_EOF to end directives, and to end
556 pre-expansion of a macro argument. Step back is not
557 unconditional, since we don't want to return a CPP_EOF to our
558 callers at the end of an -include-d file. */
559 if (pfile
->context
->prev
|| pfile
->state
.in_directive
)
560 _cpp_backup_tokens (pfile
, 1);
561 cpp_error (pfile
, DL_ERROR
,
562 "unterminated argument list invoking macro \"%s\"",
566 else if (argc
< macro
->paramc
)
568 /* As an extension, a rest argument is allowed to not appear in
569 the invocation at all.
570 e.g. #define debug(format, args...) something
573 This is exactly the same as if there had been an empty rest
574 argument - debug("string", ). */
576 if (argc
+ 1 == macro
->paramc
&& macro
->variadic
)
578 if (CPP_PEDANTIC (pfile
) && ! macro
->syshdr
)
579 cpp_error (pfile
, DL_PEDWARN
,
580 "ISO C99 requires rest arguments to be used");
584 cpp_error (pfile
, DL_ERROR
,
585 "macro \"%s\" requires %u arguments, but only %u given",
586 NODE_NAME (node
), macro
->paramc
, argc
);
590 else if (argc
> macro
->paramc
)
592 /* Empty argument to a macro taking no arguments is OK. */
593 if (argc
!= 1 || arg
->count
)
595 cpp_error (pfile
, DL_ERROR
,
596 "macro \"%s\" passed %u arguments, but takes just %u",
597 NODE_NAME (node
), argc
, macro
->paramc
);
605 _cpp_release_buff (pfile
, base_buff
);
609 /* Search for an opening parenthesis to the macro of NODE, in such a
610 way that, if none is found, we don't lose the information in any
611 intervening padding tokens. If we find the parenthesis, collect
612 the arguments and return the buffer containing them. */
614 funlike_invocation_p (pfile
, node
)
618 const cpp_token
*token
, *padding
= NULL
;
622 token
= cpp_get_token (pfile
);
623 if (token
->type
!= CPP_PADDING
)
626 || (!(padding
->flags
& PREV_WHITE
) && token
->val
.source
== NULL
))
630 if (token
->type
== CPP_OPEN_PAREN
)
632 pfile
->state
.parsing_args
= 2;
633 return collect_args (pfile
, node
);
636 /* CPP_EOF can be the end of macro arguments, or the end of the
637 file. We mustn't back up over the latter. Ugh. */
638 if (token
->type
!= CPP_EOF
|| token
== &pfile
->eof
)
640 /* Back up. We may have skipped padding, in which case backing
641 up more than one token when expanding macros is in general
642 too difficult. We re-insert it in its own context. */
643 _cpp_backup_tokens (pfile
, 1);
645 push_token_context (pfile
, NULL
, padding
, 1);
651 /* Push the context of a macro with hash entry NODE onto the context
652 stack. If we can successfully expand the macro, we push a context
653 containing its yet-to-be-rescanned replacement list and return one.
654 Otherwise, we don't push a context and return zero. */
656 enter_macro_context (pfile
, node
)
660 /* The presence of a macro invalidates a file's controlling macro. */
661 pfile
->mi_valid
= false;
663 /* Handle standard macros. */
664 if (! (node
->flags
& NODE_BUILTIN
))
666 cpp_macro
*macro
= node
->value
.macro
;
672 pfile
->state
.prevent_expansion
++;
673 pfile
->keep_tokens
++;
674 pfile
->state
.parsing_args
= 1;
675 buff
= funlike_invocation_p (pfile
, node
);
676 pfile
->state
.parsing_args
= 0;
677 pfile
->keep_tokens
--;
678 pfile
->state
.prevent_expansion
--;
682 if (CPP_WTRADITIONAL (pfile
) && ! node
->value
.macro
->syshdr
)
683 cpp_error (pfile
, DL_WARNING
,
684 "function-like macro \"%s\" must be used with arguments in traditional C",
690 if (macro
->paramc
> 0)
691 replace_args (pfile
, node
, macro
, (macro_arg
*) buff
->base
);
692 _cpp_release_buff (pfile
, buff
);
695 /* Disable the macro within its expansion. */
696 node
->flags
|= NODE_DISABLED
;
698 if (macro
->paramc
== 0)
699 push_token_context (pfile
, node
, macro
->exp
.tokens
, macro
->count
);
704 /* Handle built-in macros and the _Pragma operator. */
705 return builtin_macro (pfile
, node
);
708 /* Replace the parameters in a function-like macro of NODE with the
709 actual ARGS, and place the result in a newly pushed token context.
710 Expand each argument before replacing, unless it is operated upon
711 by the # or ## operators. */
713 replace_args (pfile
, node
, macro
, args
)
719 unsigned int i
, total
;
720 const cpp_token
*src
, *limit
;
721 const cpp_token
**dest
, **first
;
725 /* First, fully macro-expand arguments, calculating the number of
726 tokens in the final expansion as we go. The ordering of the if
727 statements below is subtle; we must handle stringification before
729 total
= macro
->count
;
730 limit
= macro
->exp
.tokens
+ macro
->count
;
732 for (src
= macro
->exp
.tokens
; src
< limit
; src
++)
733 if (src
->type
== CPP_MACRO_ARG
)
735 /* Leading and trailing padding tokens. */
738 /* We have an argument. If it is not being stringified or
739 pasted it is macro-replaced before insertion. */
740 arg
= &args
[src
->val
.arg_no
- 1];
742 if (src
->flags
& STRINGIFY_ARG
)
744 if (!arg
->stringified
)
745 arg
->stringified
= stringify_arg (pfile
, arg
);
747 else if ((src
->flags
& PASTE_LEFT
)
748 || (src
> macro
->exp
.tokens
&& (src
[-1].flags
& PASTE_LEFT
)))
749 total
+= arg
->count
- 1;
753 expand_arg (pfile
, arg
);
754 total
+= arg
->expanded_count
- 1;
758 /* Now allocate space for the expansion, copy the tokens and replace
760 buff
= _cpp_get_buff (pfile
, total
* sizeof (cpp_token
*));
761 first
= (const cpp_token
**) buff
->base
;
764 for (src
= macro
->exp
.tokens
; src
< limit
; src
++)
767 const cpp_token
**from
, **paste_flag
;
769 if (src
->type
!= CPP_MACRO_ARG
)
776 arg
= &args
[src
->val
.arg_no
- 1];
777 if (src
->flags
& STRINGIFY_ARG
)
778 count
= 1, from
= &arg
->stringified
;
779 else if (src
->flags
& PASTE_LEFT
)
780 count
= arg
->count
, from
= arg
->first
;
781 else if (src
!= macro
->exp
.tokens
&& (src
[-1].flags
& PASTE_LEFT
))
783 count
= arg
->count
, from
= arg
->first
;
786 /* GCC has special semantics for , ## b where b is a
787 varargs parameter: the comma disappears if b was
788 given no actual arguments (not merely if b is an
789 empty argument); otherwise the paste flag is removed. */
790 if (dest
[-1]->type
== CPP_COMMA
792 && src
->val
.arg_no
== macro
->paramc
)
797 paste_flag
= dest
- 1;
799 /* Remove the paste flag if the RHS is a placemarker. */
801 paste_flag
= dest
- 1;
805 count
= arg
->expanded_count
, from
= arg
->expanded
;
807 /* Padding on the left of an argument (unless RHS of ##). */
808 if (!pfile
->state
.in_directive
809 && src
!= macro
->exp
.tokens
&& !(src
[-1].flags
& PASTE_LEFT
))
810 *dest
++ = padding_token (pfile
, src
);
814 memcpy (dest
, from
, count
* sizeof (cpp_token
*));
817 /* With a non-empty argument on the LHS of ##, the last
818 token should be flagged PASTE_LEFT. */
819 if (src
->flags
& PASTE_LEFT
)
820 paste_flag
= dest
- 1;
823 /* Avoid paste on RHS (even case count == 0). */
824 if (!pfile
->state
.in_directive
&& !(src
->flags
& PASTE_LEFT
))
825 *dest
++ = &pfile
->avoid_paste
;
827 /* Add a new paste flag, or remove an unwanted one. */
830 cpp_token
*token
= _cpp_temp_token (pfile
);
831 token
->type
= (*paste_flag
)->type
;
832 token
->val
.str
= (*paste_flag
)->val
.str
;
833 if (src
->flags
& PASTE_LEFT
)
834 token
->flags
= (*paste_flag
)->flags
| PASTE_LEFT
;
836 token
->flags
= (*paste_flag
)->flags
& ~PASTE_LEFT
;
841 /* Free the expanded arguments. */
842 for (i
= 0; i
< macro
->paramc
; i
++)
843 if (args
[i
].expanded
)
844 free (args
[i
].expanded
);
846 push_ptoken_context (pfile
, node
, buff
, first
, dest
- first
);
849 /* Return a special padding token, with padding inherited from SOURCE. */
850 static const cpp_token
*
851 padding_token (pfile
, source
)
853 const cpp_token
*source
;
855 cpp_token
*result
= _cpp_temp_token (pfile
);
857 result
->type
= CPP_PADDING
;
858 result
->val
.source
= source
;
863 /* Get a new uninitialized context. Create a new one if we cannot
864 re-use an old one. */
869 cpp_context
*result
= pfile
->context
->next
;
873 result
= xnew (cpp_context
);
874 result
->prev
= pfile
->context
;
876 pfile
->context
->next
= result
;
879 pfile
->context
= result
;
883 /* Push a list of pointers to tokens. */
885 push_ptoken_context (pfile
, macro
, buff
, first
, count
)
889 const cpp_token
**first
;
892 cpp_context
*context
= next_context (pfile
);
894 context
->direct_p
= false;
895 context
->macro
= macro
;
896 context
->buff
= buff
;
897 context
->first
.ptoken
= first
;
898 context
->last
.ptoken
= first
+ count
;
901 /* Push a list of tokens. */
903 push_token_context (pfile
, macro
, first
, count
)
906 const cpp_token
*first
;
909 cpp_context
*context
= next_context (pfile
);
911 context
->direct_p
= true;
912 context
->macro
= macro
;
913 context
->buff
= NULL
;
914 context
->first
.token
= first
;
915 context
->last
.token
= first
+ count
;
918 /* Expand an argument ARG before replacing parameters in a
919 function-like macro. This works by pushing a context with the
920 argument's tokens, and then expanding that into a temporary buffer
921 as if it were a normal part of the token stream. collect_args()
922 has terminated the argument's tokens with a CPP_EOF so that we know
923 when we have fully expanded the argument. */
925 expand_arg (pfile
, arg
)
929 unsigned int capacity
;
934 /* Loop, reading in the arguments. */
936 arg
->expanded
= (const cpp_token
**)
937 xmalloc (capacity
* sizeof (cpp_token
*));
939 push_ptoken_context (pfile
, NULL
, NULL
, arg
->first
, arg
->count
+ 1);
942 const cpp_token
*token
;
944 if (arg
->expanded_count
+ 1 >= capacity
)
947 arg
->expanded
= (const cpp_token
**)
948 xrealloc (arg
->expanded
, capacity
* sizeof (cpp_token
*));
951 token
= cpp_get_token (pfile
);
953 if (token
->type
== CPP_EOF
)
956 arg
->expanded
[arg
->expanded_count
++] = token
;
959 _cpp_pop_context (pfile
);
962 /* Pop the current context off the stack, re-enabling the macro if the
963 context represented a macro's replacement list. The context
964 structure is not freed so that we can re-use it later. */
966 _cpp_pop_context (pfile
)
969 cpp_context
*context
= pfile
->context
;
972 context
->macro
->flags
&= ~NODE_DISABLED
;
975 _cpp_release_buff (pfile
, context
->buff
);
977 pfile
->context
= context
->prev
;
980 /* Eternal routine to get a token. Also used nearly everywhere
981 internally, except for places where we know we can safely call
982 the lexer directly, such as lexing a directive name.
984 Macro expansions and directives are transparently handled,
985 including entering included files. Thus tokens are post-macro
986 expansion, and after any intervening directives. External callers
987 see CPP_EOF only at EOF. Internal callers also see it when meeting
988 a directive inside a macro call, when at the end of a directive and
989 state.in_directive is still 1, and at the end of argument
992 cpp_get_token (pfile
)
995 const cpp_token
*result
;
1000 cpp_context
*context
= pfile
->context
;
1002 /* Context->prev == 0 <=> base context. */
1004 result
= _cpp_lex_token (pfile
);
1005 else if (context
->first
.token
!= context
->last
.token
)
1007 if (context
->direct_p
)
1008 result
= context
->first
.token
++;
1010 result
= *context
->first
.ptoken
++;
1012 if (result
->flags
& PASTE_LEFT
)
1014 paste_all_tokens (pfile
, result
);
1015 if (pfile
->state
.in_directive
)
1017 return padding_token (pfile
, result
);
1022 _cpp_pop_context (pfile
);
1023 if (pfile
->state
.in_directive
)
1025 return &pfile
->avoid_paste
;
1028 if (pfile
->state
.in_directive
&& result
->type
== CPP_COMMENT
)
1031 if (result
->type
!= CPP_NAME
)
1034 node
= result
->val
.node
;
1036 if (node
->type
!= NT_MACRO
|| (result
->flags
& NO_EXPAND
))
1039 if (!(node
->flags
& NODE_DISABLED
))
1041 if (!pfile
->state
.prevent_expansion
1042 && enter_macro_context (pfile
, node
))
1044 if (pfile
->state
.in_directive
)
1046 return padding_token (pfile
, result
);
1051 /* Flag this token as always unexpandable. FIXME: move this
1052 to collect_args()?. */
1053 cpp_token
*t
= _cpp_temp_token (pfile
);
1054 t
->type
= result
->type
;
1055 t
->flags
= result
->flags
| NO_EXPAND
;
1056 t
->val
.str
= result
->val
.str
;
1066 /* Returns true if we're expanding an object-like macro that was
1067 defined in a system header. Just checks the macro at the top of
1068 the stack. Used for diagnostic suppression. */
1070 cpp_sys_macro_p (pfile
)
1073 cpp_hashnode
*node
= pfile
->context
->macro
;
1075 return node
&& node
->value
.macro
&& node
->value
.macro
->syshdr
;
1078 /* Read each token in, until end of the current file. Directives are
1079 transparently processed. */
1081 cpp_scan_nooutput (pfile
)
1084 /* Request a CPP_EOF token at the end of this file, rather than
1085 transparently continuing with the including file. */
1086 pfile
->buffer
->return_at_eof
= true;
1088 while (cpp_get_token (pfile
)->type
!= CPP_EOF
)
1092 /* Step back one (or more) tokens. Can only step mack more than 1 if
1093 they are from the lexer, and not from macro expansion. */
1095 _cpp_backup_tokens (pfile
, count
)
1099 if (pfile
->context
->prev
== NULL
)
1101 pfile
->lookaheads
+= count
;
1105 if (pfile
->cur_token
== pfile
->cur_run
->base
1106 /* Possible with -fpreprocessed and no leading #line. */
1107 && pfile
->cur_run
->prev
!= NULL
)
1109 pfile
->cur_run
= pfile
->cur_run
->prev
;
1110 pfile
->cur_token
= pfile
->cur_run
->limit
;
1118 if (pfile
->context
->direct_p
)
1119 pfile
->context
->first
.token
--;
1121 pfile
->context
->first
.ptoken
--;
1125 /* #define directive parsing and handling. */
1127 /* Returns non-zero if a macro redefinition warning is required. */
1129 warn_of_redefinition (node
, macro2
)
1130 const cpp_hashnode
*node
;
1131 const cpp_macro
*macro2
;
1133 const cpp_macro
*macro1
;
1136 /* Some redefinitions need to be warned about regardless. */
1137 if (node
->flags
& NODE_WARN
)
1140 /* Redefinition of a macro is allowed if and only if the old and new
1141 definitions are the same. (6.10.3 paragraph 2). */
1142 macro1
= node
->value
.macro
;
1144 /* The quick failures. */
1145 if (macro1
->count
!= macro2
->count
1146 || macro1
->paramc
!= macro2
->paramc
1147 || macro1
->fun_like
!= macro2
->fun_like
1148 || macro1
->variadic
!= macro2
->variadic
)
1151 /* Check each token. */
1152 for (i
= 0; i
< macro1
->count
; i
++)
1153 if (! _cpp_equiv_tokens (¯o1
->exp
.tokens
[i
], ¯o2
->exp
.tokens
[i
]))
1156 /* Check parameter spellings. */
1157 for (i
= 0; i
< macro1
->paramc
; i
++)
1158 if (macro1
->params
[i
] != macro2
->params
[i
])
1164 /* Free the definition of hashnode H. */
1166 _cpp_free_definition (h
)
1169 /* Macros and assertions no longer have anything to free. */
1171 /* Clear builtin flag in case of redefinition. */
1172 h
->flags
&= ~(NODE_BUILTIN
| NODE_DISABLED
);
1175 /* Save parameter NODE to the parameter list of macro MACRO. Returns
1176 zero on success, non-zero if the parameter is a duplicate. */
1178 save_parameter (pfile
, macro
, node
)
1183 /* Constraint 6.10.3.6 - duplicate parameter names. */
1184 if (node
->arg_index
)
1186 cpp_error (pfile
, DL_ERROR
, "duplicate macro parameter \"%s\"",
1191 if (BUFF_ROOM (pfile
->a_buff
)
1192 < (macro
->paramc
+ 1) * sizeof (cpp_hashnode
*))
1193 _cpp_extend_buff (pfile
, &pfile
->a_buff
, sizeof (cpp_hashnode
*));
1195 ((cpp_hashnode
**) BUFF_FRONT (pfile
->a_buff
))[macro
->paramc
++] = node
;
1196 node
->arg_index
= macro
->paramc
;
1200 /* Check the syntax of the parameters in a MACRO definition. */
1202 parse_params (pfile
, macro
)
1206 unsigned int prev_ident
= 0;
1210 const cpp_token
*token
= _cpp_lex_token (pfile
);
1212 switch (token
->type
)
1215 /* Allow/ignore comments in parameter lists if we are
1216 preserving comments in macro expansions. */
1217 if (token
->type
== CPP_COMMENT
1218 && ! CPP_OPTION (pfile
, discard_comments_in_macro_exp
))
1221 cpp_error (pfile
, DL_ERROR
,
1222 "\"%s\" may not appear in macro parameter list",
1223 cpp_token_as_text (pfile
, token
));
1229 cpp_error (pfile
, DL_ERROR
,
1230 "macro parameters must be comma-separated");
1235 if (save_parameter (pfile
, macro
, token
->val
.node
))
1239 case CPP_CLOSE_PAREN
:
1240 if (prev_ident
|| macro
->paramc
== 0)
1243 /* Fall through to pick up the error. */
1247 cpp_error (pfile
, DL_ERROR
, "parameter name missing");
1254 macro
->variadic
= 1;
1257 save_parameter (pfile
, macro
, pfile
->spec_nodes
.n__VA_ARGS__
);
1258 pfile
->state
.va_args_ok
= 1;
1259 if (! CPP_OPTION (pfile
, c99
) && CPP_OPTION (pfile
, pedantic
))
1260 cpp_error (pfile
, DL_PEDWARN
,
1261 "anonymous variadic macros were introduced in C99");
1263 else if (CPP_OPTION (pfile
, pedantic
))
1264 cpp_error (pfile
, DL_PEDWARN
,
1265 "ISO C does not permit named variadic macros");
1267 /* We're at the end, and just expect a closing parenthesis. */
1268 token
= _cpp_lex_token (pfile
);
1269 if (token
->type
== CPP_CLOSE_PAREN
)
1274 cpp_error (pfile
, DL_ERROR
, "missing ')' in macro parameter list");
1280 /* Allocate room for a token from a macro's replacement list. */
1282 alloc_expansion_token (pfile
, macro
)
1286 if (BUFF_ROOM (pfile
->a_buff
) < (macro
->count
+ 1) * sizeof (cpp_token
))
1287 _cpp_extend_buff (pfile
, &pfile
->a_buff
, sizeof (cpp_token
));
1289 return &((cpp_token
*) BUFF_FRONT (pfile
->a_buff
))[macro
->count
++];
1292 /* Lex a token from the expansion of MACRO, but mark parameters as we
1293 find them and warn of traditional stringification. */
1295 lex_expansion_token (pfile
, macro
)
1301 pfile
->cur_token
= alloc_expansion_token (pfile
, macro
);
1302 token
= _cpp_lex_direct (pfile
);
1304 /* Is this a parameter? */
1305 if (token
->type
== CPP_NAME
&& token
->val
.node
->arg_index
)
1307 token
->type
= CPP_MACRO_ARG
;
1308 token
->val
.arg_no
= token
->val
.node
->arg_index
;
1310 else if (CPP_WTRADITIONAL (pfile
) && macro
->paramc
> 0
1311 && (token
->type
== CPP_STRING
|| token
->type
== CPP_CHAR
))
1312 check_trad_stringification (pfile
, macro
, &token
->val
.str
);
1317 /* Parse a macro and save its expansion. Returns non-zero on success. */
1319 _cpp_create_definition (pfile
, node
)
1324 cpp_token
*token
, *saved_cur_token
;
1325 const cpp_token
*ctoken
;
1326 unsigned int i
, ok
= 1;
1328 macro
= (cpp_macro
*) _cpp_aligned_alloc (pfile
, sizeof (cpp_macro
));
1329 macro
->line
= pfile
->directive_line
;
1332 macro
->variadic
= 0;
1334 macro
->fun_like
= 0;
1336 /* Get the first token of the expansion (or the '(' of a
1337 function-like macro). */
1338 ctoken
= _cpp_lex_token (pfile
);
1340 if (ctoken
->type
== CPP_OPEN_PAREN
&& !(ctoken
->flags
& PREV_WHITE
))
1342 ok
= parse_params (pfile
, macro
);
1343 macro
->params
= (cpp_hashnode
**) BUFF_FRONT (pfile
->a_buff
);
1347 /* Success. Commit the parameter array. */
1348 BUFF_FRONT (pfile
->a_buff
) = (uchar
*) ¯o
->params
[macro
->paramc
];
1349 macro
->fun_like
= 1;
1351 else if (ctoken
->type
!= CPP_EOF
&& !(ctoken
->flags
& PREV_WHITE
))
1352 cpp_error (pfile
, DL_PEDWARN
,
1353 "ISO C requires whitespace after the macro name");
1355 saved_cur_token
= pfile
->cur_token
;
1357 if (macro
->fun_like
)
1358 token
= lex_expansion_token (pfile
, macro
);
1361 token
= alloc_expansion_token (pfile
, macro
);
1367 /* Check the stringifying # constraint 6.10.3.2.1 of
1368 function-like macros when lexing the subsequent token. */
1369 if (macro
->count
> 1 && token
[-1].type
== CPP_HASH
&& macro
->fun_like
)
1371 if (token
->type
== CPP_MACRO_ARG
)
1373 token
->flags
&= ~PREV_WHITE
;
1374 token
->flags
|= STRINGIFY_ARG
;
1375 token
->flags
|= token
[-1].flags
& PREV_WHITE
;
1376 token
[-1] = token
[0];
1379 /* Let assembler get away with murder. */
1380 else if (CPP_OPTION (pfile
, lang
) != CLK_ASM
)
1383 cpp_error (pfile
, DL_ERROR
,
1384 "'#' is not followed by a macro parameter");
1389 if (token
->type
== CPP_EOF
)
1392 /* Paste operator constraint 6.10.3.3.1. */
1393 if (token
->type
== CPP_PASTE
)
1395 /* Token-paste ##, can appear in both object-like and
1396 function-like macros, but not at the ends. */
1397 if (--macro
->count
> 0)
1398 token
= lex_expansion_token (pfile
, macro
);
1400 if (macro
->count
== 0 || token
->type
== CPP_EOF
)
1403 cpp_error (pfile
, DL_ERROR
,
1404 "'##' cannot appear at either end of a macro expansion");
1408 token
[-1].flags
|= PASTE_LEFT
;
1411 token
= lex_expansion_token (pfile
, macro
);
1414 macro
->exp
.tokens
= (cpp_token
*) BUFF_FRONT (pfile
->a_buff
);
1416 /* Don't count the CPP_EOF. */
1419 /* Clear whitespace on first token for warn_of_redefinition(). */
1421 macro
->exp
.tokens
[0].flags
&= ~PREV_WHITE
;
1423 /* Commit the memory. */
1424 BUFF_FRONT (pfile
->a_buff
) = (uchar
*) ¯o
->exp
.tokens
[macro
->count
];
1426 /* Implement the macro-defined-to-itself optimisation. */
1427 if (macro
->count
== 1 && !macro
->fun_like
1428 && macro
->exp
.tokens
[0].type
== CPP_NAME
1429 && macro
->exp
.tokens
[0].val
.node
== node
)
1430 node
->flags
|= NODE_DISABLED
;
1432 /* To suppress some diagnostics. */
1433 macro
->syshdr
= pfile
->map
->sysp
!= 0;
1435 if (node
->type
!= NT_VOID
)
1437 if (warn_of_redefinition (node
, macro
))
1439 cpp_error_with_line (pfile
, DL_PEDWARN
, pfile
->directive_line
, 0,
1440 "\"%s\" redefined", NODE_NAME (node
));
1442 if (node
->type
== NT_MACRO
&& !(node
->flags
& NODE_BUILTIN
))
1443 cpp_error_with_line (pfile
, DL_PEDWARN
, node
->value
.macro
->line
, 0,
1444 "this is the location of the previous definition");
1446 _cpp_free_definition (node
);
1449 /* Enter definition in hash table. */
1450 node
->type
= NT_MACRO
;
1451 node
->value
.macro
= macro
;
1452 if (! ustrncmp (NODE_NAME (node
), DSC ("__STDC_")))
1453 node
->flags
|= NODE_WARN
;
1457 /* Set type for SEEN_EOL() in cpplib.c, restore the lexer position. */
1458 saved_cur_token
[-1].type
= pfile
->cur_token
[-1].type
;
1459 pfile
->cur_token
= saved_cur_token
;
1463 /* Stop the lexer accepting __VA_ARGS__. */
1464 pfile
->state
.va_args_ok
= 0;
1466 /* Clear the fast argument lookup indices. */
1467 for (i
= macro
->paramc
; i
-- > 0; )
1468 macro
->params
[i
]->arg_index
= 0;
1473 /* Warn if a token in STRING matches one of a function-like MACRO's
1476 check_trad_stringification (pfile
, macro
, string
)
1478 const cpp_macro
*macro
;
1479 const cpp_string
*string
;
1481 unsigned int i
, len
;
1482 const uchar
*p
, *q
, *limit
= string
->text
+ string
->len
;
1484 /* Loop over the string. */
1485 for (p
= string
->text
; p
< limit
; p
= q
)
1487 /* Find the start of an identifier. */
1488 while (p
< limit
&& !is_idstart (*p
))
1491 /* Find the end of the identifier. */
1493 while (q
< limit
&& is_idchar (*q
))
1498 /* Loop over the function macro arguments to see if the
1499 identifier inside the string matches one of them. */
1500 for (i
= 0; i
< macro
->paramc
; i
++)
1502 const cpp_hashnode
*node
= macro
->params
[i
];
1504 if (NODE_LEN (node
) == len
1505 && !memcmp (p
, NODE_NAME (node
), len
))
1507 cpp_error (pfile
, DL_WARNING
,
1508 "macro argument \"%s\" would be stringified in traditional C",
1516 /* Returns the name, arguments and expansion of a macro, in a format
1517 suitable to be read back in again, and therefore also for DWARF 2
1518 debugging info. e.g. "PASTE(X, Y) X ## Y", or "MACNAME EXPANSION".
1519 Caller is expected to generate the "#define" bit if needed. The
1520 returned text is temporary, and automatically freed later. */
1521 const unsigned char *
1522 cpp_macro_definition (pfile
, node
)
1524 const cpp_hashnode
*node
;
1526 unsigned int i
, len
;
1527 const cpp_macro
*macro
= node
->value
.macro
;
1528 unsigned char *buffer
;
1530 if (node
->type
!= NT_MACRO
|| (node
->flags
& NODE_BUILTIN
))
1532 cpp_error (pfile
, DL_ICE
,
1533 "invalid hash type %d in cpp_macro_definition", node
->type
);
1537 /* Calculate length. */
1538 len
= NODE_LEN (node
) + 1; /* ' ' */
1539 if (macro
->fun_like
)
1541 len
+= 4; /* "()" plus possible final ".." of named
1542 varargs (we have + 1 below). */
1543 for (i
= 0; i
< macro
->paramc
; i
++)
1544 len
+= NODE_LEN (macro
->params
[i
]) + 1; /* "," */
1547 for (i
= 0; i
< macro
->count
; i
++)
1549 cpp_token
*token
= ¯o
->exp
.tokens
[i
];
1551 if (token
->type
== CPP_MACRO_ARG
)
1552 len
+= NODE_LEN (macro
->params
[token
->val
.arg_no
- 1]);
1554 len
+= cpp_token_len (token
); /* Includes room for ' '. */
1555 if (token
->flags
& STRINGIFY_ARG
)
1557 if (token
->flags
& PASTE_LEFT
)
1558 len
+= 3; /* " ##" */
1561 if (len
> pfile
->macro_buffer_len
)
1563 pfile
->macro_buffer
= (uchar
*) xrealloc (pfile
->macro_buffer
, len
);
1564 pfile
->macro_buffer_len
= len
;
1567 /* Fill in the buffer. Start with the macro name. */
1568 buffer
= pfile
->macro_buffer
;
1569 memcpy (buffer
, NODE_NAME (node
), NODE_LEN (node
));
1570 buffer
+= NODE_LEN (node
);
1572 /* Parameter names. */
1573 if (macro
->fun_like
)
1576 for (i
= 0; i
< macro
->paramc
; i
++)
1578 cpp_hashnode
*param
= macro
->params
[i
];
1580 if (param
!= pfile
->spec_nodes
.n__VA_ARGS__
)
1582 memcpy (buffer
, NODE_NAME (param
), NODE_LEN (param
));
1583 buffer
+= NODE_LEN (param
);
1586 if (i
+ 1 < macro
->paramc
)
1587 /* Don't emit a space after the comma here; we're trying
1588 to emit a Dwarf-friendly definition, and the Dwarf spec
1589 forbids spaces in the argument list. */
1591 else if (macro
->variadic
)
1592 *buffer
++ = '.', *buffer
++ = '.', *buffer
++ = '.';
1597 /* The Dwarf spec requires a space after the macro name, even if the
1598 definition is the empty string. */
1601 /* Expansion tokens. */
1604 for (i
= 0; i
< macro
->count
; i
++)
1606 cpp_token
*token
= ¯o
->exp
.tokens
[i
];
1608 if (token
->flags
& PREV_WHITE
)
1610 if (token
->flags
& STRINGIFY_ARG
)
1613 if (token
->type
== CPP_MACRO_ARG
)
1615 len
= NODE_LEN (macro
->params
[token
->val
.arg_no
- 1]);
1617 NODE_NAME (macro
->params
[token
->val
.arg_no
- 1]), len
);
1621 buffer
= cpp_spell_token (pfile
, token
, buffer
);
1623 if (token
->flags
& PASTE_LEFT
)
1628 /* Next has PREV_WHITE; see _cpp_create_definition. */
1634 return pfile
->macro_buffer
;