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 *stringify_arg PARAMS ((cpp_reader *, macro_arg *));
58 static void paste_all_tokens PARAMS ((cpp_reader *, const cpp_token *));
59 static bool paste_tokens PARAMS ((cpp_reader *, const cpp_token **,
61 static void replace_args PARAMS ((cpp_reader *, cpp_hashnode *, cpp_macro *,
63 static _cpp_buff *funlike_invocation_p PARAMS ((cpp_reader *, cpp_hashnode *));
64 static bool create_iso_definition PARAMS ((cpp_reader *, cpp_macro *));
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 bool warn_of_redefinition PARAMS ((cpp_reader *, const cpp_hashnode *,
72 static bool parse_params PARAMS ((cpp_reader *, cpp_macro *));
73 static void check_trad_stringification PARAMS ((cpp_reader *,
77 /* Emits a warning if NODE is a macro defined in the main file that
80 _cpp_warn_if_unused_macro (pfile, node, v)
83 void *v ATTRIBUTE_UNUSED;
85 if (node->type == NT_MACRO && !(node->flags & NODE_BUILTIN))
87 cpp_macro *macro = node->value.macro;
90 /* Skip front-end built-ins and command line macros. */
91 && macro->line >= pfile->first_unused_line
92 && MAIN_FILE_P (lookup_line (&pfile->line_maps, macro->line)))
93 cpp_error_with_line (pfile, DL_WARNING, macro->line, 0,
94 "macro \"%s\" is not used", NODE_NAME (node));
100 /* Allocates and returns a CPP_STRING token, containing TEXT of length
101 LEN, after null-terminating it. TEXT must be in permanent storage. */
102 static const cpp_token *
103 new_string_token (pfile, text, len)
108 cpp_token *token = _cpp_temp_token (pfile);
111 token->type = CPP_STRING;
112 token->val.str.len = len;
113 token->val.str.text = text;
118 static const char * const monthnames[] =
120 "Jan", "Feb", "Mar", "Apr", "May", "Jun",
121 "Jul", "Aug", "Sep", "Oct", "Nov", "Dec"
124 /* Handle builtin macros like __FILE__, and push the resulting token
125 on the context stack. Also handles _Pragma, for which no new token
126 is created. Returns 1 if it generates a new token context, 0 to
127 return the token to the caller. */
129 _cpp_builtin_macro_text (pfile, node)
133 const uchar *result = NULL;
134 unsigned int number = 1;
136 switch (node->value.builtin)
139 cpp_error (pfile, DL_ICE, "invalid built-in macro \"%s\"",
149 const struct line_map *map = pfile->map;
151 if (node->value.builtin == BT_BASE_FILE)
152 while (! MAIN_FILE_P (map))
153 map = INCLUDED_FROM (&pfile->line_maps, map);
157 buf = _cpp_unaligned_alloc (pfile, len * 4 + 3);
160 buf = cpp_quote_string (buf + 1, (const unsigned char *) name, len);
166 case BT_INCLUDE_LEVEL:
167 /* The line map depth counts the primary source as level 1, but
168 historically __INCLUDE_DEPTH__ has called the primary source
170 number = pfile->line_maps.depth - 1;
174 /* If __LINE__ is embedded in a macro, it must expand to the
175 line of the macro's invocation, not its definition.
176 Otherwise things like assert() will not work properly. */
177 if (CPP_OPTION (pfile, traditional))
178 number = pfile->line;
180 number = pfile->cur_token[-1].line;
181 number = SOURCE_LINE (pfile->map, number);
184 /* __STDC__ has the value 1 under normal circumstances.
185 However, if (a) we are in a system header, (b) the option
186 stdc_0_in_system_headers is true (set by target config), and
187 (c) we are not in strictly conforming mode, then it has the
191 enum c_lang lang = CPP_OPTION (pfile, lang);
192 if (CPP_IN_SYSTEM_HEADER (pfile)
193 && CPP_OPTION (pfile, stdc_0_in_system_headers)
194 && !CPP_OPTION (pfile,std))
203 if (pfile->date == NULL)
205 /* Allocate __DATE__ and __TIME__ strings from permanent
206 storage. We only do this once, and don't generate them
207 at init time, because time() and localtime() are very
208 slow on some systems. */
210 struct tm *tb = NULL;
212 /* (time_t) -1 is a legitimate value for "number of seconds
213 since the Epoch", so we have to do a little dance to
214 distinguish that from a genuine error. */
217 if (tt != (time_t)-1 || errno == 0)
218 tb = localtime (&tt);
222 pfile->date = _cpp_unaligned_alloc (pfile,
223 sizeof ("\"Oct 11 1347\""));
224 sprintf ((char *) pfile->date, "\"%s %2d %4d\"",
225 monthnames[tb->tm_mon], tb->tm_mday, tb->tm_year + 1900);
227 pfile->time = _cpp_unaligned_alloc (pfile,
228 sizeof ("\"12:34:56\""));
229 sprintf ((char *) pfile->time, "\"%02d:%02d:%02d\"",
230 tb->tm_hour, tb->tm_min, tb->tm_sec);
234 cpp_errno (pfile, DL_WARNING,
235 "could not determine date and time");
237 pfile->date = U"\"??? ?? ????\"";
238 pfile->time = U"\"??:??:??\"";
242 if (node->value.builtin == BT_DATE)
243 result = pfile->date;
245 result = pfile->time;
251 /* 21 bytes holds all NUL-terminated unsigned 64-bit numbers. */
252 result = _cpp_unaligned_alloc (pfile, 21);
253 sprintf ((char *) result, "%u", number);
259 /* Convert builtin macros like __FILE__ to a token and push it on the
260 context stack. Also handles _Pragma, for which no new token is
261 created. Returns 1 if it generates a new token context, 0 to
262 return the token to the caller. */
264 builtin_macro (pfile, node)
270 if (node->value.builtin == BT_PRAGMA)
272 /* Don't interpret _Pragma within directives. The standard is
273 not clear on this, but to me this makes most sense. */
274 if (pfile->state.in_directive)
277 _cpp_do__Pragma (pfile);
281 buf = _cpp_builtin_macro_text (pfile, node);
283 cpp_push_buffer (pfile, buf, ustrlen (buf), /* from_stage3 */ true, 1);
285 /* Tweak the column number the lexer will report. */
286 pfile->buffer->col_adjust = pfile->cur_token[-1].col - 1;
288 /* We don't want a leading # to be interpreted as a directive. */
289 pfile->buffer->saved_flags = 0;
291 /* Set pfile->cur_token as required by _cpp_lex_direct. */
292 pfile->cur_token = _cpp_temp_token (pfile);
293 push_token_context (pfile, NULL, _cpp_lex_direct (pfile), 1);
294 if (pfile->buffer->cur != pfile->buffer->rlimit)
295 cpp_error (pfile, DL_ICE, "invalid built-in macro \"%s\"",
297 _cpp_pop_buffer (pfile);
302 /* Copies SRC, of length LEN, to DEST, adding backslashes before all
303 backslashes and double quotes. Non-printable characters are
304 converted to octal. DEST must be of sufficient size. Returns
305 a pointer to the end of the string. */
307 cpp_quote_string (dest, src, len)
316 if (c == '\\' || c == '"')
327 sprintf ((char *) dest, "\\%03o", c);
336 /* Convert a token sequence ARG to a single string token according to
337 the rules of the ISO C #-operator. */
338 static const cpp_token *
339 stringify_arg (pfile, arg)
343 unsigned char *dest = BUFF_FRONT (pfile->u_buff);
344 unsigned int i, escape_it, backslash_count = 0;
345 const cpp_token *source = NULL;
348 /* Loop, reading in the argument's tokens. */
349 for (i = 0; i < arg->count; i++)
351 const cpp_token *token = arg->first[i];
353 if (token->type == CPP_PADDING)
356 source = token->val.source;
360 escape_it = (token->type == CPP_STRING || token->type == CPP_WSTRING
361 || token->type == CPP_CHAR || token->type == CPP_WCHAR);
363 /* Room for each char being written in octal, initial space and
365 len = cpp_token_len (token);
370 if ((size_t) (BUFF_LIMIT (pfile->u_buff) - dest) < len)
372 size_t len_so_far = dest - BUFF_FRONT (pfile->u_buff);
373 _cpp_extend_buff (pfile, &pfile->u_buff, len);
374 dest = BUFF_FRONT (pfile->u_buff) + len_so_far;
377 /* Leading white space? */
378 if (dest != BUFF_FRONT (pfile->u_buff))
382 if (source->flags & PREV_WHITE)
389 _cpp_buff *buff = _cpp_get_buff (pfile, len);
390 unsigned char *buf = BUFF_FRONT (buff);
391 len = cpp_spell_token (pfile, token, buf) - buf;
392 dest = cpp_quote_string (dest, buf, len);
393 _cpp_release_buff (pfile, buff);
396 dest = cpp_spell_token (pfile, token, dest);
398 if (token->type == CPP_OTHER && token->val.c == '\\')
404 /* Ignore the final \ of invalid string literals. */
405 if (backslash_count & 1)
407 cpp_error (pfile, DL_WARNING,
408 "invalid string literal, ignoring final '\\'");
412 /* Commit the memory, including NUL, and return the token. */
413 len = dest - BUFF_FRONT (pfile->u_buff);
414 BUFF_FRONT (pfile->u_buff) = dest + 1;
415 return new_string_token (pfile, dest - len, len);
418 /* Try to paste two tokens. On success, return non-zero. In any
419 case, PLHS is updated to point to the pasted token, which is
420 guaranteed to not have the PASTE_LEFT flag set. */
422 paste_tokens (pfile, plhs, rhs)
424 const cpp_token **plhs, *rhs;
426 unsigned char *buf, *end;
427 const cpp_token *lhs;
432 len = cpp_token_len (lhs) + cpp_token_len (rhs) + 1;
433 buf = (unsigned char *) alloca (len);
434 end = cpp_spell_token (pfile, lhs, buf);
436 /* Avoid comment headers, since they are still processed in stage 3.
437 It is simpler to insert a space here, rather than modifying the
438 lexer to ignore comments in some circumstances. Simply returning
439 false doesn't work, since we want to clear the PASTE_LEFT flag. */
440 if (lhs->type == CPP_DIV
441 && (rhs->type == CPP_MULT || rhs->type == CPP_DIV))
443 end = cpp_spell_token (pfile, rhs, end);
446 cpp_push_buffer (pfile, buf, end - buf, /* from_stage3 */ true, 1);
448 /* Tweak the column number the lexer will report. */
449 pfile->buffer->col_adjust = pfile->cur_token[-1].col - 1;
451 /* We don't want a leading # to be interpreted as a directive. */
452 pfile->buffer->saved_flags = 0;
454 /* Set pfile->cur_token as required by _cpp_lex_direct. */
455 pfile->cur_token = _cpp_temp_token (pfile);
456 *plhs = _cpp_lex_direct (pfile);
457 valid = pfile->buffer->cur == pfile->buffer->rlimit;
458 _cpp_pop_buffer (pfile);
463 /* Handles an arbitrarily long sequence of ## operators, with initial
464 operand LHS. This implementation is left-associative,
465 non-recursive, and finishes a paste before handling succeeding
466 ones. If a paste fails, we back up to the RHS of the failing ##
467 operator before pushing the context containing the result of prior
468 successful pastes, with the effect that the RHS appears in the
469 output stream after the pasted LHS normally. */
471 paste_all_tokens (pfile, lhs)
473 const cpp_token *lhs;
475 const cpp_token *rhs;
476 cpp_context *context = pfile->context;
480 /* Take the token directly from the current context. We can do
481 this, because we are in the replacement list of either an
482 object-like macro, or a function-like macro with arguments
483 inserted. In either case, the constraints to #define
484 guarantee we have at least one more token. */
485 if (context->direct_p)
486 rhs = FIRST (context).token++;
488 rhs = *FIRST (context).ptoken++;
490 if (rhs->type == CPP_PADDING)
493 if (!paste_tokens (pfile, &lhs, rhs))
495 _cpp_backup_tokens (pfile, 1);
497 /* Mandatory error for all apart from assembler. */
498 if (CPP_OPTION (pfile, lang) != CLK_ASM)
499 cpp_error (pfile, DL_ERROR,
500 "pasting \"%s\" and \"%s\" does not give a valid preprocessing token",
501 cpp_token_as_text (pfile, lhs),
502 cpp_token_as_text (pfile, rhs));
506 while (rhs->flags & PASTE_LEFT);
508 /* Put the resulting token in its own context. */
509 push_token_context (pfile, NULL, lhs, 1);
512 /* Returns TRUE if the number of arguments ARGC supplied in an
513 invocation of the MACRO referenced by NODE is valid. An empty
514 invocation to a macro with no parameters should pass ARGC as zero.
516 Note that MACRO cannot necessarily be deduced from NODE, in case
517 NODE was redefined whilst collecting arguments. */
519 _cpp_arguments_ok (pfile, macro, node, argc)
522 const cpp_hashnode *node;
525 if (argc == macro->paramc)
528 if (argc < macro->paramc)
530 /* As an extension, a rest argument is allowed to not appear in
531 the invocation at all.
532 e.g. #define debug(format, args...) something
535 This is exactly the same as if there had been an empty rest
536 argument - debug("string", ). */
538 if (argc + 1 == macro->paramc && macro->variadic)
540 if (CPP_PEDANTIC (pfile) && ! macro->syshdr)
541 cpp_error (pfile, DL_PEDWARN,
542 "ISO C99 requires rest arguments to be used");
546 cpp_error (pfile, DL_ERROR,
547 "macro \"%s\" requires %u arguments, but only %u given",
548 NODE_NAME (node), macro->paramc, argc);
551 cpp_error (pfile, DL_ERROR,
552 "macro \"%s\" passed %u arguments, but takes just %u",
553 NODE_NAME (node), argc, macro->paramc);
558 /* Reads and returns the arguments to a function-like macro
559 invocation. Assumes the opening parenthesis has been processed.
560 If there is an error, emits an appropriate diagnostic and returns
561 NULL. Each argument is terminated by a CPP_EOF token, for the
562 future benefit of expand_arg(). */
564 collect_args (pfile, node)
566 const cpp_hashnode *node;
568 _cpp_buff *buff, *base_buff;
570 macro_arg *args, *arg;
571 const cpp_token *token;
574 macro = node->value.macro;
576 argc = macro->paramc;
579 buff = _cpp_get_buff (pfile, argc * (50 * sizeof (cpp_token *)
580 + sizeof (macro_arg)));
582 args = (macro_arg *) buff->base;
583 memset (args, 0, argc * sizeof (macro_arg));
584 buff->cur = (unsigned char *) &args[argc];
585 arg = args, argc = 0;
587 /* Collect the tokens making up each argument. We don't yet know
588 how many arguments have been supplied, whether too many or too
589 few. Hence the slightly bizarre usage of "argc" and "arg". */
592 unsigned int paren_depth = 0;
593 unsigned int ntokens = 0;
596 arg->first = (const cpp_token **) buff->cur;
600 /* Require space for 2 new tokens (including a CPP_EOF). */
601 if ((unsigned char *) &arg->first[ntokens + 2] > buff->limit)
603 buff = _cpp_append_extend_buff (pfile, buff,
604 1000 * sizeof (cpp_token *));
605 arg->first = (const cpp_token **) buff->cur;
608 token = cpp_get_token (pfile);
610 if (token->type == CPP_PADDING)
612 /* Drop leading padding. */
616 else if (token->type == CPP_OPEN_PAREN)
618 else if (token->type == CPP_CLOSE_PAREN)
620 if (paren_depth-- == 0)
623 else if (token->type == CPP_COMMA)
625 /* A comma does not terminate an argument within
626 parentheses or as part of a variable argument. */
628 && ! (macro->variadic && argc == macro->paramc))
631 else if (token->type == CPP_EOF
632 || (token->type == CPP_HASH && token->flags & BOL))
635 arg->first[ntokens++] = token;
638 /* Drop trailing padding. */
639 while (ntokens > 0 && arg->first[ntokens - 1]->type == CPP_PADDING)
642 arg->count = ntokens;
643 arg->first[ntokens] = &pfile->eof;
645 /* Terminate the argument. Excess arguments loop back and
646 overwrite the final legitimate argument, before failing. */
647 if (argc <= macro->paramc)
649 buff->cur = (unsigned char *) &arg->first[ntokens + 1];
650 if (argc != macro->paramc)
654 while (token->type != CPP_CLOSE_PAREN && token->type != CPP_EOF);
656 if (token->type == CPP_EOF)
658 /* We still need the CPP_EOF to end directives, and to end
659 pre-expansion of a macro argument. Step back is not
660 unconditional, since we don't want to return a CPP_EOF to our
661 callers at the end of an -include-d file. */
662 if (pfile->context->prev || pfile->state.in_directive)
663 _cpp_backup_tokens (pfile, 1);
664 cpp_error (pfile, DL_ERROR,
665 "unterminated argument list invoking macro \"%s\"",
670 /* A single empty argument is counted as no argument. */
671 if (argc == 1 && macro->paramc == 0 && args[0].count == 0)
673 if (_cpp_arguments_ok (pfile, macro, node, argc))
675 /* GCC has special semantics for , ## b where b is a varargs
676 parameter: we remove the comma if b was omitted entirely.
677 If b was merely an empty argument, the comma is retained.
678 If the macro takes just one (varargs) parameter, then we
679 retain the comma only if we are standards conforming.
681 If FIRST is NULL replace_args () swallows the comma. */
682 if (macro->variadic && (argc < macro->paramc
683 || (argc == 1 && args[0].count == 0
684 && !CPP_OPTION (pfile, std))))
685 args[macro->paramc - 1].first = NULL;
690 /* An error occurred. */
691 _cpp_release_buff (pfile, base_buff);
695 /* Search for an opening parenthesis to the macro of NODE, in such a
696 way that, if none is found, we don't lose the information in any
697 intervening padding tokens. If we find the parenthesis, collect
698 the arguments and return the buffer containing them. */
700 funlike_invocation_p (pfile, node)
704 const cpp_token *token, *padding = NULL;
708 token = cpp_get_token (pfile);
709 if (token->type != CPP_PADDING)
712 || (!(padding->flags & PREV_WHITE) && token->val.source == NULL))
716 if (token->type == CPP_OPEN_PAREN)
718 pfile->state.parsing_args = 2;
719 return collect_args (pfile, node);
722 /* CPP_EOF can be the end of macro arguments, or the end of the
723 file. We mustn't back up over the latter. Ugh. */
724 if (token->type != CPP_EOF || token == &pfile->eof)
726 /* Back up. We may have skipped padding, in which case backing
727 up more than one token when expanding macros is in general
728 too difficult. We re-insert it in its own context. */
729 _cpp_backup_tokens (pfile, 1);
731 push_token_context (pfile, NULL, padding, 1);
737 /* Push the context of a macro with hash entry NODE onto the context
738 stack. If we can successfully expand the macro, we push a context
739 containing its yet-to-be-rescanned replacement list and return one.
740 Otherwise, we don't push a context and return zero. */
742 enter_macro_context (pfile, node)
746 /* The presence of a macro invalidates a file's controlling macro. */
747 pfile->mi_valid = false;
749 pfile->state.angled_headers = false;
751 /* Handle standard macros. */
752 if (! (node->flags & NODE_BUILTIN))
754 cpp_macro *macro = node->value.macro;
760 pfile->state.prevent_expansion++;
761 pfile->keep_tokens++;
762 pfile->state.parsing_args = 1;
763 buff = funlike_invocation_p (pfile, node);
764 pfile->state.parsing_args = 0;
765 pfile->keep_tokens--;
766 pfile->state.prevent_expansion--;
770 if (CPP_WTRADITIONAL (pfile) && ! node->value.macro->syshdr)
771 cpp_error (pfile, DL_WARNING,
772 "function-like macro \"%s\" must be used with arguments in traditional C",
778 if (macro->paramc > 0)
779 replace_args (pfile, node, macro, (macro_arg *) buff->base);
780 _cpp_release_buff (pfile, buff);
783 /* Disable the macro within its expansion. */
784 node->flags |= NODE_DISABLED;
788 if (macro->paramc == 0)
789 push_token_context (pfile, node, macro->exp.tokens, macro->count);
794 /* Handle built-in macros and the _Pragma operator. */
795 return builtin_macro (pfile, node);
798 /* Replace the parameters in a function-like macro of NODE with the
799 actual ARGS, and place the result in a newly pushed token context.
800 Expand each argument before replacing, unless it is operated upon
801 by the # or ## operators. */
803 replace_args (pfile, node, macro, args)
809 unsigned int i, total;
810 const cpp_token *src, *limit;
811 const cpp_token **dest, **first;
815 /* First, fully macro-expand arguments, calculating the number of
816 tokens in the final expansion as we go. The ordering of the if
817 statements below is subtle; we must handle stringification before
819 total = macro->count;
820 limit = macro->exp.tokens + macro->count;
822 for (src = macro->exp.tokens; src < limit; src++)
823 if (src->type == CPP_MACRO_ARG)
825 /* Leading and trailing padding tokens. */
828 /* We have an argument. If it is not being stringified or
829 pasted it is macro-replaced before insertion. */
830 arg = &args[src->val.arg_no - 1];
832 if (src->flags & STRINGIFY_ARG)
834 if (!arg->stringified)
835 arg->stringified = stringify_arg (pfile, arg);
837 else if ((src->flags & PASTE_LEFT)
838 || (src > macro->exp.tokens && (src[-1].flags & PASTE_LEFT)))
839 total += arg->count - 1;
843 expand_arg (pfile, arg);
844 total += arg->expanded_count - 1;
848 /* Now allocate space for the expansion, copy the tokens and replace
850 buff = _cpp_get_buff (pfile, total * sizeof (cpp_token *));
851 first = (const cpp_token **) buff->base;
854 for (src = macro->exp.tokens; src < limit; src++)
857 const cpp_token **from, **paste_flag;
859 if (src->type != CPP_MACRO_ARG)
866 arg = &args[src->val.arg_no - 1];
867 if (src->flags & STRINGIFY_ARG)
868 count = 1, from = &arg->stringified;
869 else if (src->flags & PASTE_LEFT)
870 count = arg->count, from = arg->first;
871 else if (src != macro->exp.tokens && (src[-1].flags & PASTE_LEFT))
873 count = arg->count, from = arg->first;
876 if (dest[-1]->type == CPP_COMMA
878 && src->val.arg_no == macro->paramc)
880 /* Swallow a pasted comma if from == NULL, otherwise
881 drop the paste flag. */
885 paste_flag = dest - 1;
887 /* Remove the paste flag if the RHS is a placemarker. */
889 paste_flag = dest - 1;
893 count = arg->expanded_count, from = arg->expanded;
895 /* Padding on the left of an argument (unless RHS of ##). */
896 if (!pfile->state.in_directive
897 && src != macro->exp.tokens && !(src[-1].flags & PASTE_LEFT))
898 *dest++ = padding_token (pfile, src);
902 memcpy (dest, from, count * sizeof (cpp_token *));
905 /* With a non-empty argument on the LHS of ##, the last
906 token should be flagged PASTE_LEFT. */
907 if (src->flags & PASTE_LEFT)
908 paste_flag = dest - 1;
911 /* Avoid paste on RHS (even case count == 0). */
912 if (!pfile->state.in_directive && !(src->flags & PASTE_LEFT))
913 *dest++ = &pfile->avoid_paste;
915 /* Add a new paste flag, or remove an unwanted one. */
918 cpp_token *token = _cpp_temp_token (pfile);
919 token->type = (*paste_flag)->type;
920 token->val.str = (*paste_flag)->val.str;
921 if (src->flags & PASTE_LEFT)
922 token->flags = (*paste_flag)->flags | PASTE_LEFT;
924 token->flags = (*paste_flag)->flags & ~PASTE_LEFT;
929 /* Free the expanded arguments. */
930 for (i = 0; i < macro->paramc; i++)
931 if (args[i].expanded)
932 free (args[i].expanded);
934 push_ptoken_context (pfile, node, buff, first, dest - first);
937 /* Return a special padding token, with padding inherited from SOURCE. */
938 static const cpp_token *
939 padding_token (pfile, source)
941 const cpp_token *source;
943 cpp_token *result = _cpp_temp_token (pfile);
945 result->type = CPP_PADDING;
946 result->val.source = source;
951 /* Get a new uninitialized context. Create a new one if we cannot
952 re-use an old one. */
957 cpp_context *result = pfile->context->next;
961 result = xnew (cpp_context);
962 result->prev = pfile->context;
964 pfile->context->next = result;
967 pfile->context = result;
971 /* Push a list of pointers to tokens. */
973 push_ptoken_context (pfile, macro, buff, first, count)
977 const cpp_token **first;
980 cpp_context *context = next_context (pfile);
982 context->direct_p = false;
983 context->macro = macro;
984 context->buff = buff;
985 FIRST (context).ptoken = first;
986 LAST (context).ptoken = first + count;
989 /* Push a list of tokens. */
991 push_token_context (pfile, macro, first, count)
994 const cpp_token *first;
997 cpp_context *context = next_context (pfile);
999 context->direct_p = true;
1000 context->macro = macro;
1001 context->buff = NULL;
1002 FIRST (context).token = first;
1003 LAST (context).token = first + count;
1006 /* Push a traditional macro's replacement text. */
1008 _cpp_push_text_context (pfile, macro, start, len)
1010 cpp_hashnode *macro;
1014 cpp_context *context = next_context (pfile);
1016 context->direct_p = true;
1017 context->macro = macro;
1018 context->buff = NULL;
1019 CUR (context) = start;
1020 RLIMIT (context) = start + len;
1021 macro->flags |= NODE_DISABLED;
1024 /* Expand an argument ARG before replacing parameters in a
1025 function-like macro. This works by pushing a context with the
1026 argument's tokens, and then expanding that into a temporary buffer
1027 as if it were a normal part of the token stream. collect_args()
1028 has terminated the argument's tokens with a CPP_EOF so that we know
1029 when we have fully expanded the argument. */
1031 expand_arg (pfile, arg)
1035 unsigned int capacity;
1037 if (arg->count == 0)
1040 /* Loop, reading in the arguments. */
1042 arg->expanded = (const cpp_token **)
1043 xmalloc (capacity * sizeof (cpp_token *));
1045 push_ptoken_context (pfile, NULL, NULL, arg->first, arg->count + 1);
1048 const cpp_token *token;
1050 if (arg->expanded_count + 1 >= capacity)
1053 arg->expanded = (const cpp_token **)
1054 xrealloc (arg->expanded, capacity * sizeof (cpp_token *));
1057 token = cpp_get_token (pfile);
1059 if (token->type == CPP_EOF)
1062 arg->expanded[arg->expanded_count++] = token;
1065 _cpp_pop_context (pfile);
1068 /* Pop the current context off the stack, re-enabling the macro if the
1069 context represented a macro's replacement list. The context
1070 structure is not freed so that we can re-use it later. */
1072 _cpp_pop_context (pfile)
1075 cpp_context *context = pfile->context;
1078 context->macro->flags &= ~NODE_DISABLED;
1081 _cpp_release_buff (pfile, context->buff);
1083 pfile->context = context->prev;
1086 /* Eternal routine to get a token. Also used nearly everywhere
1087 internally, except for places where we know we can safely call
1088 the lexer directly, such as lexing a directive name.
1090 Macro expansions and directives are transparently handled,
1091 including entering included files. Thus tokens are post-macro
1092 expansion, and after any intervening directives. External callers
1093 see CPP_EOF only at EOF. Internal callers also see it when meeting
1094 a directive inside a macro call, when at the end of a directive and
1095 state.in_directive is still 1, and at the end of argument
1098 cpp_get_token (pfile)
1101 const cpp_token *result;
1106 cpp_context *context = pfile->context;
1108 /* Context->prev == 0 <=> base context. */
1110 result = _cpp_lex_token (pfile);
1111 else if (FIRST (context).token != LAST (context).token)
1113 if (context->direct_p)
1114 result = FIRST (context).token++;
1116 result = *FIRST (context).ptoken++;
1118 if (result->flags & PASTE_LEFT)
1120 paste_all_tokens (pfile, result);
1121 if (pfile->state.in_directive)
1123 return padding_token (pfile, result);
1128 _cpp_pop_context (pfile);
1129 if (pfile->state.in_directive)
1131 return &pfile->avoid_paste;
1134 if (pfile->state.in_directive && result->type == CPP_COMMENT)
1137 if (result->type != CPP_NAME)
1140 node = result->val.node;
1142 if (node->type != NT_MACRO || (result->flags & NO_EXPAND))
1145 if (!(node->flags & NODE_DISABLED))
1147 if (!pfile->state.prevent_expansion
1148 && enter_macro_context (pfile, node))
1150 if (pfile->state.in_directive)
1152 return padding_token (pfile, result);
1157 /* Flag this token as always unexpandable. FIXME: move this
1158 to collect_args()?. */
1159 cpp_token *t = _cpp_temp_token (pfile);
1160 t->type = result->type;
1161 t->flags = result->flags | NO_EXPAND;
1162 t->val.str = result->val.str;
1172 /* Returns true if we're expanding an object-like macro that was
1173 defined in a system header. Just checks the macro at the top of
1174 the stack. Used for diagnostic suppression. */
1176 cpp_sys_macro_p (pfile)
1179 cpp_hashnode *node = pfile->context->macro;
1181 return node && node->value.macro && node->value.macro->syshdr;
1184 /* Read each token in, until end of the current file. Directives are
1185 transparently processed. */
1187 cpp_scan_nooutput (pfile)
1190 /* Request a CPP_EOF token at the end of this file, rather than
1191 transparently continuing with the including file. */
1192 pfile->buffer->return_at_eof = true;
1194 if (CPP_OPTION (pfile, traditional))
1195 while (_cpp_read_logical_line_trad (pfile))
1198 while (cpp_get_token (pfile)->type != CPP_EOF)
1202 /* Step back one (or more) tokens. Can only step mack more than 1 if
1203 they are from the lexer, and not from macro expansion. */
1205 _cpp_backup_tokens (pfile, count)
1209 if (pfile->context->prev == NULL)
1211 pfile->lookaheads += count;
1215 if (pfile->cur_token == pfile->cur_run->base
1216 /* Possible with -fpreprocessed and no leading #line. */
1217 && pfile->cur_run->prev != NULL)
1219 pfile->cur_run = pfile->cur_run->prev;
1220 pfile->cur_token = pfile->cur_run->limit;
1228 if (pfile->context->direct_p)
1229 FIRST (pfile->context).token--;
1231 FIRST (pfile->context).ptoken--;
1235 /* #define directive parsing and handling. */
1237 /* Returns non-zero if a macro redefinition warning is required. */
1239 warn_of_redefinition (pfile, node, macro2)
1241 const cpp_hashnode *node;
1242 const cpp_macro *macro2;
1244 const cpp_macro *macro1;
1247 /* Some redefinitions need to be warned about regardless. */
1248 if (node->flags & NODE_WARN)
1251 /* Redefinition of a macro is allowed if and only if the old and new
1252 definitions are the same. (6.10.3 paragraph 2). */
1253 macro1 = node->value.macro;
1255 /* Don't check count here as it can be different in valid
1256 traditional redefinitions with just whitespace differences. */
1257 if (macro1->paramc != macro2->paramc
1258 || macro1->fun_like != macro2->fun_like
1259 || macro1->variadic != macro2->variadic)
1262 /* Check parameter spellings. */
1263 for (i = 0; i < macro1->paramc; i++)
1264 if (macro1->params[i] != macro2->params[i])
1267 /* Check the replacement text or tokens. */
1268 if (CPP_OPTION (pfile, traditional))
1269 return _cpp_expansions_different_trad (macro1, macro2);
1271 if (macro1->count == macro2->count)
1272 for (i = 0; i < macro1->count; i++)
1273 if (!_cpp_equiv_tokens (¯o1->exp.tokens[i], ¯o2->exp.tokens[i]))
1279 /* Free the definition of hashnode H. */
1281 _cpp_free_definition (h)
1284 /* Macros and assertions no longer have anything to free. */
1286 /* Clear builtin flag in case of redefinition. */
1287 h->flags &= ~(NODE_BUILTIN | NODE_DISABLED);
1290 /* Save parameter NODE to the parameter list of macro MACRO. Returns
1291 zero on success, non-zero if the parameter is a duplicate. */
1293 _cpp_save_parameter (pfile, macro, node)
1298 /* Constraint 6.10.3.6 - duplicate parameter names. */
1299 if (node->arg_index)
1301 cpp_error (pfile, DL_ERROR, "duplicate macro parameter \"%s\"",
1306 if (BUFF_ROOM (pfile->a_buff)
1307 < (macro->paramc + 1) * sizeof (cpp_hashnode *))
1308 _cpp_extend_buff (pfile, &pfile->a_buff, sizeof (cpp_hashnode *));
1310 ((cpp_hashnode **) BUFF_FRONT (pfile->a_buff))[macro->paramc++] = node;
1311 node->arg_index = macro->paramc;
1315 /* Check the syntax of the parameters in a MACRO definition. Returns
1316 false if an error occurs. */
1318 parse_params (pfile, macro)
1322 unsigned int prev_ident = 0;
1326 const cpp_token *token = _cpp_lex_token (pfile);
1328 switch (token->type)
1331 /* Allow/ignore comments in parameter lists if we are
1332 preserving comments in macro expansions. */
1333 if (token->type == CPP_COMMENT
1334 && ! CPP_OPTION (pfile, discard_comments_in_macro_exp))
1337 cpp_error (pfile, DL_ERROR,
1338 "\"%s\" may not appear in macro parameter list",
1339 cpp_token_as_text (pfile, token));
1345 cpp_error (pfile, DL_ERROR,
1346 "macro parameters must be comma-separated");
1351 if (_cpp_save_parameter (pfile, macro, token->val.node))
1355 case CPP_CLOSE_PAREN:
1356 if (prev_ident || macro->paramc == 0)
1359 /* Fall through to pick up the error. */
1363 cpp_error (pfile, DL_ERROR, "parameter name missing");
1370 macro->variadic = 1;
1373 _cpp_save_parameter (pfile, macro,
1374 pfile->spec_nodes.n__VA_ARGS__);
1375 pfile->state.va_args_ok = 1;
1376 if (! CPP_OPTION (pfile, c99) && CPP_OPTION (pfile, pedantic))
1377 cpp_error (pfile, DL_PEDWARN,
1378 "anonymous variadic macros were introduced in C99");
1380 else if (CPP_OPTION (pfile, pedantic))
1381 cpp_error (pfile, DL_PEDWARN,
1382 "ISO C does not permit named variadic macros");
1384 /* We're at the end, and just expect a closing parenthesis. */
1385 token = _cpp_lex_token (pfile);
1386 if (token->type == CPP_CLOSE_PAREN)
1391 cpp_error (pfile, DL_ERROR, "missing ')' in macro parameter list");
1397 /* Allocate room for a token from a macro's replacement list. */
1399 alloc_expansion_token (pfile, macro)
1403 if (BUFF_ROOM (pfile->a_buff) < (macro->count + 1) * sizeof (cpp_token))
1404 _cpp_extend_buff (pfile, &pfile->a_buff, sizeof (cpp_token));
1406 return &((cpp_token *) BUFF_FRONT (pfile->a_buff))[macro->count++];
1409 /* Lex a token from the expansion of MACRO, but mark parameters as we
1410 find them and warn of traditional stringification. */
1412 lex_expansion_token (pfile, macro)
1418 pfile->cur_token = alloc_expansion_token (pfile, macro);
1419 token = _cpp_lex_direct (pfile);
1421 /* Is this a parameter? */
1422 if (token->type == CPP_NAME && token->val.node->arg_index)
1424 token->type = CPP_MACRO_ARG;
1425 token->val.arg_no = token->val.node->arg_index;
1427 else if (CPP_WTRADITIONAL (pfile) && macro->paramc > 0
1428 && (token->type == CPP_STRING || token->type == CPP_CHAR))
1429 check_trad_stringification (pfile, macro, &token->val.str);
1435 create_iso_definition (pfile, macro)
1440 const cpp_token *ctoken;
1442 /* Get the first token of the expansion (or the '(' of a
1443 function-like macro). */
1444 ctoken = _cpp_lex_token (pfile);
1446 if (ctoken->type == CPP_OPEN_PAREN && !(ctoken->flags & PREV_WHITE))
1448 bool ok = parse_params (pfile, macro);
1449 macro->params = (cpp_hashnode **) BUFF_FRONT (pfile->a_buff);
1453 /* Success. Commit the parameter array. */
1454 BUFF_FRONT (pfile->a_buff) = (uchar *) ¯o->params[macro->paramc];
1455 macro->fun_like = 1;
1457 else if (ctoken->type != CPP_EOF && !(ctoken->flags & PREV_WHITE))
1458 cpp_error (pfile, DL_PEDWARN,
1459 "ISO C requires whitespace after the macro name");
1461 if (macro->fun_like)
1462 token = lex_expansion_token (pfile, macro);
1465 token = alloc_expansion_token (pfile, macro);
1471 /* Check the stringifying # constraint 6.10.3.2.1 of
1472 function-like macros when lexing the subsequent token. */
1473 if (macro->count > 1 && token[-1].type == CPP_HASH && macro->fun_like)
1475 if (token->type == CPP_MACRO_ARG)
1477 token->flags &= ~PREV_WHITE;
1478 token->flags |= STRINGIFY_ARG;
1479 token->flags |= token[-1].flags & PREV_WHITE;
1480 token[-1] = token[0];
1483 /* Let assembler get away with murder. */
1484 else if (CPP_OPTION (pfile, lang) != CLK_ASM)
1486 cpp_error (pfile, DL_ERROR,
1487 "'#' is not followed by a macro parameter");
1492 if (token->type == CPP_EOF)
1495 /* Paste operator constraint 6.10.3.3.1. */
1496 if (token->type == CPP_PASTE)
1498 /* Token-paste ##, can appear in both object-like and
1499 function-like macros, but not at the ends. */
1500 if (--macro->count > 0)
1501 token = lex_expansion_token (pfile, macro);
1503 if (macro->count == 0 || token->type == CPP_EOF)
1505 cpp_error (pfile, DL_ERROR,
1506 "'##' cannot appear at either end of a macro expansion");
1510 token[-1].flags |= PASTE_LEFT;
1513 token = lex_expansion_token (pfile, macro);
1516 macro->exp.tokens = (cpp_token *) BUFF_FRONT (pfile->a_buff);
1518 /* Don't count the CPP_EOF. */
1521 /* Clear whitespace on first token for warn_of_redefinition(). */
1523 macro->exp.tokens[0].flags &= ~PREV_WHITE;
1525 /* Commit the memory. */
1526 BUFF_FRONT (pfile->a_buff) = (uchar *) ¯o->exp.tokens[macro->count];
1531 /* Parse a macro and save its expansion. Returns non-zero on success. */
1533 _cpp_create_definition (pfile, node)
1541 macro = (cpp_macro *) _cpp_aligned_alloc (pfile, sizeof (cpp_macro));
1542 macro->line = pfile->directive_line;
1545 macro->variadic = 0;
1548 macro->fun_like = 0;
1549 /* To suppress some diagnostics. */
1550 macro->syshdr = pfile->map->sysp != 0;
1552 if (CPP_OPTION (pfile, traditional))
1553 ok = _cpp_create_trad_definition (pfile, macro);
1556 cpp_token *saved_cur_token = pfile->cur_token;
1558 ok = create_iso_definition (pfile, macro);
1560 /* Restore lexer position because of games lex_expansion_token()
1561 plays lexing the macro. We set the type for SEEN_EOL() in
1564 Longer term we should lex the whole line before coming here,
1565 and just copy the expansion. */
1566 saved_cur_token[-1].type = pfile->cur_token[-1].type;
1567 pfile->cur_token = saved_cur_token;
1569 /* Stop the lexer accepting __VA_ARGS__. */
1570 pfile->state.va_args_ok = 0;
1573 /* Clear the fast argument lookup indices. */
1574 for (i = macro->paramc; i-- > 0; )
1575 macro->params[i]->arg_index = 0;
1580 if (node->type == NT_MACRO)
1582 if (CPP_OPTION (pfile, warn_unused_macros))
1583 _cpp_warn_if_unused_macro (pfile, node, NULL);
1585 if (warn_of_redefinition (pfile, node, macro))
1587 cpp_error_with_line (pfile, DL_PEDWARN, pfile->directive_line, 0,
1588 "\"%s\" redefined", NODE_NAME (node));
1590 if (node->type == NT_MACRO && !(node->flags & NODE_BUILTIN))
1591 cpp_error_with_line (pfile, DL_PEDWARN,
1592 node->value.macro->line, 0,
1593 "this is the location of the previous definition");
1597 if (node->type != NT_VOID)
1598 _cpp_free_definition (node);
1600 /* Enter definition in hash table. */
1601 node->type = NT_MACRO;
1602 node->value.macro = macro;
1603 if (! ustrncmp (NODE_NAME (node), DSC ("__STDC_")))
1604 node->flags |= NODE_WARN;
1609 /* Warn if a token in STRING matches one of a function-like MACRO's
1612 check_trad_stringification (pfile, macro, string)
1614 const cpp_macro *macro;
1615 const cpp_string *string;
1617 unsigned int i, len;
1618 const uchar *p, *q, *limit = string->text + string->len;
1620 /* Loop over the string. */
1621 for (p = string->text; p < limit; p = q)
1623 /* Find the start of an identifier. */
1624 while (p < limit && !is_idstart (*p))
1627 /* Find the end of the identifier. */
1629 while (q < limit && is_idchar (*q))
1634 /* Loop over the function macro arguments to see if the
1635 identifier inside the string matches one of them. */
1636 for (i = 0; i < macro->paramc; i++)
1638 const cpp_hashnode *node = macro->params[i];
1640 if (NODE_LEN (node) == len
1641 && !memcmp (p, NODE_NAME (node), len))
1643 cpp_error (pfile, DL_WARNING,
1644 "macro argument \"%s\" would be stringified in traditional C",
1652 /* Returns the name, arguments and expansion of a macro, in a format
1653 suitable to be read back in again, and therefore also for DWARF 2
1654 debugging info. e.g. "PASTE(X, Y) X ## Y", or "MACNAME EXPANSION".
1655 Caller is expected to generate the "#define" bit if needed. The
1656 returned text is temporary, and automatically freed later. */
1657 const unsigned char *
1658 cpp_macro_definition (pfile, node)
1660 const cpp_hashnode *node;
1662 unsigned int i, len;
1663 const cpp_macro *macro = node->value.macro;
1664 unsigned char *buffer;
1666 if (node->type != NT_MACRO || (node->flags & NODE_BUILTIN))
1668 cpp_error (pfile, DL_ICE,
1669 "invalid hash type %d in cpp_macro_definition", node->type);
1673 /* Calculate length. */
1674 len = NODE_LEN (node) + 2; /* ' ' and NUL. */
1675 if (macro->fun_like)
1677 len += 4; /* "()" plus possible final ".." of named
1678 varargs (we have + 1 below). */
1679 for (i = 0; i < macro->paramc; i++)
1680 len += NODE_LEN (macro->params[i]) + 1; /* "," */
1683 if (CPP_OPTION (pfile, traditional))
1684 len += _cpp_replacement_text_len (macro);
1687 for (i = 0; i < macro->count; i++)
1689 cpp_token *token = ¯o->exp.tokens[i];
1691 if (token->type == CPP_MACRO_ARG)
1692 len += NODE_LEN (macro->params[token->val.arg_no - 1]);
1694 len += cpp_token_len (token); /* Includes room for ' '. */
1695 if (token->flags & STRINGIFY_ARG)
1697 if (token->flags & PASTE_LEFT)
1698 len += 3; /* " ##" */
1702 if (len > pfile->macro_buffer_len)
1704 pfile->macro_buffer = (uchar *) xrealloc (pfile->macro_buffer, len);
1705 pfile->macro_buffer_len = len;
1708 /* Fill in the buffer. Start with the macro name. */
1709 buffer = pfile->macro_buffer;
1710 memcpy (buffer, NODE_NAME (node), NODE_LEN (node));
1711 buffer += NODE_LEN (node);
1713 /* Parameter names. */
1714 if (macro->fun_like)
1717 for (i = 0; i < macro->paramc; i++)
1719 cpp_hashnode *param = macro->params[i];
1721 if (param != pfile->spec_nodes.n__VA_ARGS__)
1723 memcpy (buffer, NODE_NAME (param), NODE_LEN (param));
1724 buffer += NODE_LEN (param);
1727 if (i + 1 < macro->paramc)
1728 /* Don't emit a space after the comma here; we're trying
1729 to emit a Dwarf-friendly definition, and the Dwarf spec
1730 forbids spaces in the argument list. */
1732 else if (macro->variadic)
1733 *buffer++ = '.', *buffer++ = '.', *buffer++ = '.';
1738 /* The Dwarf spec requires a space after the macro name, even if the
1739 definition is the empty string. */
1742 if (CPP_OPTION (pfile, traditional))
1743 buffer = _cpp_copy_replacement_text (macro, buffer);
1744 else if (macro->count)
1745 /* Expansion tokens. */
1747 for (i = 0; i < macro->count; i++)
1749 cpp_token *token = ¯o->exp.tokens[i];
1751 if (token->flags & PREV_WHITE)
1753 if (token->flags & STRINGIFY_ARG)
1756 if (token->type == CPP_MACRO_ARG)
1758 len = NODE_LEN (macro->params[token->val.arg_no - 1]);
1760 NODE_NAME (macro->params[token->val.arg_no - 1]), len);
1764 buffer = cpp_spell_token (pfile, token, buffer);
1766 if (token->flags & PASTE_LEFT)
1771 /* Next has PREV_WHITE; see _cpp_create_definition. */
1777 return pfile->macro_buffer;