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 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! */
28 #include "intl.h" /* for _("<command line>") below. */
32 #ifndef STDC_0_IN_SYSTEM_HEADERS
33 #define STDC_0_IN_SYSTEM_HEADERS 0 /* Boolean macro. */
38 cpp_hashnode **params; /* Parameters, if any. */
39 cpp_token *expansion; /* First token of replacement list. */
40 const char *file; /* Defined in file name. */
41 unsigned int line; /* Starting line number. */
42 unsigned int count; /* Number of tokens in expansion. */
43 unsigned short paramc; /* Number of parameters. */
44 unsigned int fun_like : 1; /* If a function-like macro. */
45 unsigned int variadic : 1; /* If a variadic macro. */
46 unsigned int disabled : 1; /* If macro is disabled. */
49 typedef struct macro_arg macro_arg;
52 cpp_token *first; /* First token in unexpanded argument. */
53 cpp_token *expanded; /* Macro-expanded argument. */
54 cpp_token *stringified; /* Stringified argument. */
55 unsigned int count; /* # of tokens in argument. */
56 unsigned int expanded_count; /* # of tokens in expanded argument. */
59 /* Macro expansion. */
61 static void lock_pools PARAMS ((cpp_reader *));
62 static void unlock_pools PARAMS ((cpp_reader *));
63 static int enter_macro_context PARAMS ((cpp_reader *, cpp_hashnode *));
64 static void builtin_macro PARAMS ((cpp_reader *, cpp_token *));
65 static cpp_context *push_arg_context PARAMS ((cpp_reader *, macro_arg *));
66 static enum cpp_ttype parse_arg PARAMS ((cpp_reader *, macro_arg *, int));
67 static macro_arg *parse_args PARAMS ((cpp_reader *, const cpp_hashnode *));
68 static cpp_context *next_context PARAMS ((cpp_reader *));
69 static void expand_arg PARAMS ((cpp_reader *, macro_arg *));
70 static unsigned char *quote_string PARAMS ((unsigned char *,
71 const unsigned char *,
73 static void make_string_token PARAMS ((cpp_pool *, cpp_token *,
74 const U_CHAR *, unsigned int));
75 static void make_number_token PARAMS ((cpp_reader *, cpp_token *, int));
76 static void stringify_arg PARAMS ((cpp_reader *, macro_arg *));
77 static void paste_all_tokens PARAMS ((cpp_reader *, cpp_token *));
78 static int paste_tokens PARAMS ((cpp_reader *, cpp_token *, cpp_token *));
79 static int funlike_invocation_p PARAMS ((cpp_reader *, const cpp_hashnode *,
81 static void replace_args PARAMS ((cpp_reader *, cpp_macro *, macro_arg *,
86 static void save_lookahead_token PARAMS ((cpp_reader *, const cpp_token *));
87 static void take_lookahead_token PARAMS ((cpp_reader *, cpp_token *));
88 static cpp_lookahead *alloc_lookahead PARAMS ((cpp_reader *));
89 static void free_lookahead PARAMS ((cpp_lookahead *));
91 /* #define directive parsing and handling. */
93 static cpp_token *lex_expansion_token PARAMS ((cpp_reader *, cpp_macro *));
94 static int check_macro_redefinition PARAMS ((cpp_reader *,
97 static int save_parameter PARAMS ((cpp_reader *, cpp_macro *, cpp_hashnode *));
98 static int parse_params PARAMS ((cpp_reader *, cpp_macro *));
99 static void check_trad_stringification PARAMS ((cpp_reader *,
101 const cpp_string *));
103 /* Allocates a buffer to hold a token's TEXT, and converts TOKEN to a
104 CPP_STRING token containing TEXT in quoted form. */
106 make_string_token (pool, token, text, len)
112 U_CHAR *buf = _cpp_pool_alloc (pool, len * 4);
114 token->type = CPP_STRING;
115 token->val.str.text = buf;
116 token->val.str.len = quote_string (buf, text, len) - buf;
120 /* Allocates and converts a temporary token to a CPP_NUMBER token,
121 evaluating to NUMBER. */
123 make_number_token (pfile, token, number)
128 unsigned char *buf = _cpp_pool_alloc (&pfile->ident_pool, 20);
130 sprintf ((char *) buf, "%d", number);
131 token->type = CPP_NUMBER;
132 token->val.str.text = buf;
133 token->val.str.len = ustrlen (buf);
137 static const char * const monthnames[] =
139 "Jan", "Feb", "Mar", "Apr", "May", "Jun",
140 "Jul", "Aug", "Sep", "Oct", "Nov", "Dec"
143 /* Handle builtin macros like __FILE__. */
145 builtin_macro (pfile, token)
149 cpp_hashnode *node = token->val.node;
151 switch (node->value.builtin)
157 cpp_buffer *buffer = pfile->buffer;
159 if (node->value.builtin == BT_BASE_FILE)
161 buffer = buffer->prev;
163 name = buffer->nominal_fname;
164 make_string_token (&pfile->ident_pool, token,
165 (const unsigned char *) name, strlen (name));
169 case BT_INCLUDE_LEVEL:
170 /* pfile->include_depth counts the primary source as level 1,
171 but historically __INCLUDE_DEPTH__ has called the primary
173 make_number_token (pfile, token, pfile->include_depth - 1);
177 /* If __LINE__ is embedded in a macro, it must expand to the
178 line of the macro's invocation, not its definition.
179 Otherwise things like assert() will not work properly. */
180 make_number_token (pfile, token, cpp_get_line (pfile)->line);
187 if (STDC_0_IN_SYSTEM_HEADERS && CPP_IN_SYSTEM_HEADER (pfile)
188 && pfile->spec_nodes.n__STRICT_ANSI__->type == NT_VOID)
190 make_number_token (pfile, token, stdc);
196 if (pfile->date.type == CPP_EOF)
198 /* Allocate __DATE__ and __TIME__ from permanent storage,
199 and save them in pfile so we don't have to do this again.
200 We don't generate these strings at init time because
201 time() and localtime() are very slow on some systems. */
202 time_t tt = time (NULL);
203 struct tm *tb = localtime (&tt);
205 make_string_token (&pfile->ident_pool, &pfile->date,
207 make_string_token (&pfile->ident_pool, &pfile->time,
210 sprintf ((char *) pfile->date.val.str.text, "%s %2d %4d",
211 monthnames[tb->tm_mon], tb->tm_mday, tb->tm_year + 1900);
212 sprintf ((char *) pfile->time.val.str.text, "%02d:%02d:%02d",
213 tb->tm_hour, tb->tm_min, tb->tm_sec);
215 *token = node->value.builtin == BT_DATE ? pfile->date: pfile->time;
219 cpp_ice (pfile, "invalid builtin macro \"%s\"", node->name);
224 /* Used by cpperror.c to obtain the correct line and column to report
226 const cpp_lexer_pos *
230 return &pfile->lexer_pos;
237 _cpp_lock_pool (&pfile->argument_pool);
244 _cpp_unlock_pool (&pfile->argument_pool);
247 /* Adds backslashes before all backslashes and double quotes appearing
248 in strings. Non-printable characters are converted to octal. */
250 quote_string (dest, src, len)
259 if (c == '\\' || c == '"')
270 sprintf ((char *) dest, "\\%03o", c);
279 /* Convert a token sequence to a single string token according to the
280 rules of the ISO C #-operator. */
282 stringify_arg (pfile, arg)
286 cpp_pool *pool = &pfile->ident_pool;
287 unsigned char *start = POOL_FRONT (pool);
288 unsigned int i, escape_it, total_len = 0, backslash_count = 0;
290 /* Loop, reading in the argument's tokens. */
291 for (i = 0; i < arg->count; i++)
294 const cpp_token *token = &arg->first[i];
295 unsigned int len = cpp_token_len (token);
297 escape_it = (token->type == CPP_STRING || token->type == CPP_WSTRING
298 || token->type == CPP_CHAR || token->type == CPP_WCHAR
299 || token->type == CPP_OSTRING);
302 /* Worst case is each char is octal. */
304 len++; /* Room for initial space. */
306 dest = &start[total_len];
307 if (dest + len > POOL_LIMIT (pool))
309 _cpp_next_chunk (pool, len, (unsigned char **) &start);
310 dest = &start[total_len];
313 /* No leading white space. */
314 if (token->flags & PREV_WHITE && total_len > 0)
319 unsigned char *buf = (unsigned char *) xmalloc (len);
321 len = cpp_spell_token (pfile, token, buf) - buf;
322 dest = quote_string (dest, buf, len);
326 dest = cpp_spell_token (pfile, token, dest);
327 total_len = dest - start;
329 if (token->type == CPP_OTHER && token->val.c == '\\')
335 /* Ignore the final \ of invalid string literals. */
336 if (backslash_count & 1)
338 cpp_warning (pfile, "invalid string literal, ignoring final '\\'");
342 POOL_COMMIT (pool, total_len);
344 arg->stringified = xnew (cpp_token);
345 arg->stringified->flags = 0;
346 arg->stringified->type = CPP_STRING;
347 arg->stringified->val.str.text = start;
348 arg->stringified->val.str.len = total_len;
351 /* Try to paste two tokens. On success, the LHS becomes the pasted
352 token, and 0 is returned. For failure, we update the flags of the
353 RHS appropriately and return non-zero. */
355 paste_tokens (pfile, lhs, rhs)
357 cpp_token *lhs, *rhs;
363 type = cpp_can_paste (pfile, lhs, rhs, &digraph);
367 /* Mandatory warning for all apart from assembler. */
368 if (CPP_OPTION (pfile, lang) != CLK_ASM)
370 "pasting \"%s\" and \"%s\" does not give a valid preprocessing token",
371 cpp_token_as_text (pfile, lhs),
372 cpp_token_as_text (pfile, rhs));
374 /* The standard states that behaviour is undefined. By the
375 principle of least surpise, we step back before the RHS, and
376 mark it to prevent macro expansion. Tests in the testsuite
377 rely on clearing PREV_WHITE here, though you could argue we
378 should actually set it. Assembler can have '.' in labels and
379 so requires that we don't insert spaces there. Maybe we should
380 change this to put out a space unless it's assembler. */
381 rhs->flags &= ~PREV_WHITE;
382 rhs->flags |= NO_EXPAND;
386 flags = lhs->flags & ~DIGRAPH;
390 /* Identifiers and numbers need spellings to be pasted. */
391 if (type == CPP_NAME || type == CPP_NUMBER)
393 unsigned int total_len = cpp_token_len (lhs) + cpp_token_len (rhs);
394 unsigned char *result, *end;
396 result = _cpp_pool_alloc (&pfile->ident_pool, total_len + 1);
398 /* Paste the spellings and null terminate. */
399 end = cpp_spell_token (pfile, rhs, cpp_spell_token (pfile, lhs, result));
401 total_len = end - result;
403 if (type == CPP_NAME)
405 lhs->val.node = cpp_lookup (pfile, result, total_len);
406 if (lhs->val.node->flags & NODE_OPERATOR)
409 lhs->type = lhs->val.node->value.operator;
414 lhs->val.str.text = result;
415 lhs->val.str.len = total_len;
418 else if (type == CPP_WCHAR || type == CPP_WSTRING)
419 lhs->val.str = rhs->val.str;
421 /* Set type and flags after pasting spellings. */
428 /* Handles an arbitrarily long sequence of ## operators. This
429 implementation is left-associative, non-recursive, and finishes a
430 paste before handling succeeding ones. If the paste fails, we back
431 up a token to just after the ## operator, with the effect that it
432 appears in the output stream normally. */
434 paste_all_tokens (pfile, lhs)
439 unsigned char orig_flags = lhs->flags;
443 /* Take the token directly from the current context. We can do
444 this, because we are in the replacement list of either an
445 object-like macro, or a function-like macro with arguments
446 inserted. In either case, the constraints to #define
447 guarantee we have at least one more token. */
448 rhs = pfile->context->list.first++;
449 if (paste_tokens (pfile, lhs, rhs))
451 /* We failed. Step back so we read the RHS in next. */
452 pfile->context->list.first--;
456 while (rhs->flags & PASTE_LEFT);
458 /* The pasted token has the PREV_WHITE flag of the LHS, is no longer
459 PASTE_LEFT, and is subject to macro expansion. */
460 lhs->flags &= ~(PREV_WHITE | PASTE_LEFT | NO_EXPAND);
461 lhs->flags |= orig_flags & PREV_WHITE;
464 /* Reads the unexpanded tokens of a macro argument into ARG. VAR_ARGS
465 is non-zero if this is a variadic macro. Returns the type of the
466 token that caused reading to finish. */
467 static enum cpp_ttype
468 parse_arg (pfile, arg, variadic)
470 struct macro_arg *arg;
473 enum cpp_ttype result;
474 unsigned int paren = 0;
477 arg->first = (cpp_token *) POOL_FRONT (&pfile->argument_pool);
478 for (;; arg->count++)
480 cpp_token *token = &arg->first[arg->count];
481 if ((unsigned char *) (token + 1) >= POOL_LIMIT (&pfile->argument_pool))
483 _cpp_next_chunk (&pfile->argument_pool, sizeof (cpp_token),
484 (unsigned char **) &arg->first);
485 token = &arg->first[arg->count];
488 /* Newlines in arguments are white space (6.10.3.10). */
489 line = pfile->lexer_pos.output_line;
490 cpp_get_token (pfile, token);
491 if (line != pfile->lexer_pos.output_line)
492 token->flags |= PREV_WHITE;
494 result = token->type;
495 if (result == CPP_OPEN_PAREN)
497 else if (result == CPP_CLOSE_PAREN && paren-- == 0)
499 /* Commas are not terminators within parantheses or variadic. */
500 else if (result == CPP_COMMA && paren == 0 && !variadic)
502 else if (result == CPP_EOF)
503 break; /* Error reported by caller. */
506 /* Commit the memory used to store the arguments. */
507 POOL_COMMIT (&pfile->argument_pool, arg->count * sizeof (cpp_token));
512 /* Parse the arguments making up a macro invocation. */
514 parse_args (pfile, node)
516 const cpp_hashnode *node;
518 cpp_macro *macro = node->value.macro;
519 macro_arg *args, *cur;
523 /* Allocate room for at least one argument, and zero it out. */
524 argc = macro->paramc ? macro->paramc: 1;
525 args = xcnewvec (macro_arg, argc);
527 for (cur = args, argc = 0; ;)
531 type = parse_arg (pfile, cur, argc == macro->paramc && macro->variadic);
532 if (type == CPP_CLOSE_PAREN || type == CPP_EOF)
535 /* Re-use the last argument for excess arguments. */
536 if (argc < macro->paramc)
542 cpp_error (pfile, "unterminated argument list invoking macro \"%s\"",
546 else if (argc < macro->paramc)
548 /* As an extension, a rest argument is allowed to not appear in
549 the invocation at all.
550 e.g. #define debug(format, args...) something
553 This is exactly the same as if there had been an empty rest
554 argument - debug("string", ). */
556 if (argc + 1 == macro->paramc && macro->variadic)
558 if (CPP_PEDANTIC (pfile))
559 cpp_pedwarn (pfile, "ISO C99 requires rest arguments to be used");
564 "macro \"%s\" requires %u arguments, but only %u given",
565 node->name, macro->paramc, argc);
569 else if (argc > macro->paramc)
571 /* Empty argument to a macro taking no arguments is OK. */
572 if (argc != 1 || cur->count)
575 "macro \"%s\" passed %u arguments, but takes just %u",
576 node->name, argc, macro->paramc);
591 funlike_invocation_p (pfile, node, list)
593 const cpp_hashnode *node;
594 struct toklist *list;
597 cpp_token maybe_paren;
599 cpp_lexer_pos macro_pos;
601 macro_pos = pfile->lexer_pos;
602 pfile->state.parsing_args = 1;
603 pfile->state.prevent_expansion++;
604 orig = pfile->context;
606 cpp_start_lookahead (pfile);
607 cpp_get_token (pfile, &maybe_paren);
608 cpp_stop_lookahead (pfile, maybe_paren.type == CPP_OPEN_PAREN);
610 if (maybe_paren.type == CPP_OPEN_PAREN)
611 args = parse_args (pfile, node);
612 else if (CPP_WTRADITIONAL (pfile))
614 "function-like macro \"%s\" must be used with arguments in traditional C",
617 /* Restore original context. */
618 pfile->context = orig;
619 pfile->state.prevent_expansion--;
620 pfile->state.parsing_args = 0;
624 /* The macro's expansion appears where the name would have. */
625 pfile->lexer_pos = macro_pos;
627 if (node->value.macro->paramc > 0)
629 /* Don't save tokens during pre-expansion. */
630 struct cpp_lookahead *la_saved = pfile->la_write;
632 replace_args (pfile, node->value.macro, args, list);
633 pfile->la_write = la_saved;
641 /* Push the context of a macro onto the context stack. TOKEN is the
642 macro name. If we can successfully start expanding the macro,
643 TOKEN is replaced with the first token of the expansion, and we
646 enter_macro_context (pfile, node)
650 cpp_context *context;
651 cpp_macro *macro = node->value.macro;
654 /* Save the position of the outermost macro invocation. */
655 if (!pfile->context->prev)
658 if (macro->fun_like && !funlike_invocation_p (pfile, node, &list))
660 if (!pfile->context->prev)
661 unlock_pools (pfile);
665 if (macro->paramc == 0)
667 list.first = macro->expansion;
668 list.limit = macro->expansion + macro->count;
671 /* Only push a macro context for non-empty replacement lists. */
672 if (list.first != list.limit)
674 context = next_context (pfile);
675 context->list = list;
676 context->macro = macro;
678 /* Disable the macro within its expansion. */
685 /* Move to the next context. Create one if there is none. */
690 cpp_context *prev = pfile->context;
691 cpp_context *result = prev->next;
695 result = xnew (cpp_context);
701 pfile->context = result;
706 replace_args (pfile, macro, args, list)
710 struct toklist *list;
712 unsigned char flags = 0;
713 unsigned int i, total;
714 const cpp_token *src, *limit;
718 src = macro->expansion;
719 limit = src + macro->count;
721 /* First, fully macro-expand arguments, calculating the number of
722 tokens in the final expansion as we go. This ensures that the
723 possible recursive use of argument_pool is fine. */
725 for (; src < limit; src++)
726 if (src->type == CPP_MACRO_ARG)
728 /* We have an argument. If it is not being stringified or
729 pasted it is macro-replaced before insertion. */
730 arg = &args[src->val.arg_no - 1];
732 if (src->flags & STRINGIFY_ARG)
734 if (!arg->stringified)
735 stringify_arg (pfile, arg);
737 else if ((src->flags & PASTE_LEFT)
738 || (src > macro->expansion && (src[-1].flags & PASTE_LEFT)))
739 total += arg->count - 1;
744 arg->expanded_count = 0;
746 expand_arg (pfile, arg);
748 total += arg->expanded_count - 1;
752 dest = (cpp_token *) _cpp_pool_alloc (&pfile->argument_pool,
753 total * sizeof (cpp_token));
756 for (src = macro->expansion; src < limit; src++)
757 if (src->type == CPP_MACRO_ARG)
760 const cpp_token *from;
762 arg = &args[src->val.arg_no - 1];
763 if (src->flags & STRINGIFY_ARG)
764 from = arg->stringified, count = 1;
765 else if (src->flags & PASTE_LEFT)
766 count = arg->count, from = arg->first;
767 else if (src > macro->expansion && (src[-1].flags & PASTE_LEFT))
769 count = arg->count, from = arg->first;
770 if (dest != list->first)
772 /* GCC has special semantics for , ## b where b is a
773 varargs parameter: the comma disappears if b was
774 given no actual arguments (not merely if b is an
775 empty argument); otherwise pasting is turned off. */
776 if (dest[-1].type == CPP_COMMA
778 && src->val.arg_no == macro->paramc)
783 dest[-1].flags &= ~PASTE_LEFT;
785 /* Count == 0 is the RHS a placemarker case. */
787 dest[-1].flags &= ~PASTE_LEFT;
791 count = arg->expanded_count, from = arg->expanded;
793 /* Count == 0 is the LHS a placemarker case. */
796 memcpy (dest, from, count * sizeof (cpp_token));
798 /* The first token gets PREV_WHITE of the CPP_MACRO_ARG. */
799 dest->flags &= ~PREV_WHITE;
800 dest->flags |= src->flags & PREV_WHITE;
802 /* The last token gets the PASTE_LEFT of the CPP_MACRO_ARG. */
803 dest[count - 1].flags |= src->flags & PASTE_LEFT;
805 dest[0].flags |= AVOID_LPASTE;
809 /* The token after the argument must avoid an accidental paste. */
810 flags = AVOID_LPASTE;
815 dest->flags |= flags;
822 /* Free the expanded arguments. */
823 for (i = 0; i < macro->paramc; i++)
825 if (args[i].expanded)
826 free (args[i].expanded);
827 if (args[i].stringified)
828 free (args[i].stringified);
832 /* Subroutine of expand_arg to put the unexpanded tokens on the
835 push_arg_context (pfile, arg)
839 cpp_context *context = next_context (pfile);
841 context->list.first = arg->first;
842 context->list.limit = arg->first + arg->count;
848 expand_arg (pfile, arg)
853 unsigned int capacity = 256;
855 /* Loop, reading in the arguments. */
856 arg->expanded = (cpp_token *) xmalloc (capacity * sizeof (cpp_token));
858 push_arg_context (pfile, arg);
861 if (arg->expanded_count >= capacity)
864 arg->expanded = (cpp_token *)
865 xrealloc (arg->expanded, capacity * sizeof (cpp_token));
867 token = &arg->expanded[arg->expanded_count++];
868 cpp_get_token (pfile, token);
870 while (token->type != CPP_EOF);
872 arg->expanded_count--;
874 /* Pop the context we pushed. */
875 pfile->context = pfile->context->prev;
879 _cpp_pop_context (pfile)
882 cpp_context *context = pfile->context;
884 pfile->context = context->prev;
885 if (!pfile->context->prev && !pfile->state.parsing_args)
886 unlock_pools (pfile);
888 /* Re-enable a macro, temporarily if parsing_args, when leaving its
890 context->macro->disabled = 0;
893 /* Eternal routine to get a token. Also used nearly everywhere
894 internally, except for places where we know we can safely call
895 the lexer directly, such as lexing a directive name.
897 Macro expansions and directives are transparently handled,
898 including entering included files. Thus tokens are post-macro
899 expansion, and after any intervening directives. External callers
900 see CPP_EOF only at EOF. Internal callers also see it when meeting
901 a directive inside a macro call, when at the end of a directive and
902 state.in_directive is still 1, and at the end of argument
905 cpp_get_token (pfile, token)
909 unsigned char flags = 0;
913 cpp_context *context = pfile->context;
916 take_lookahead_token (pfile, token);
917 /* Context->prev == 0 <=> base context. */
918 else if (!context->prev)
919 _cpp_lex_token (pfile, token);
920 else if (context->list.first != context->list.limit)
922 *token = *context->list.first++;
923 /* PASTE_LEFT tokens can only appear in macro expansions. */
924 if (token->flags & PASTE_LEFT)
925 paste_all_tokens (pfile, token);
931 /* Avoid accidental paste at the end of a macro. */
932 flags |= AVOID_LPASTE;
933 _cpp_pop_context (pfile);
936 /* End of argument pre-expansion. */
937 token->type = CPP_EOF;
942 token->flags |= flags;
944 if (token->type != CPP_NAME)
947 /* Handle macros and the _Pragma operator. */
948 if (token->val.node->type == NT_MACRO
949 && !pfile->state.prevent_expansion
950 && !(token->flags & NO_EXPAND))
952 cpp_hashnode *node = token->val.node;
954 /* Macros invalidate controlling macros. */
955 pfile->mi_state = MI_FAILED;
957 /* Remember PREV_WHITE and avoid an accidental paste. */
958 flags = (token->flags & PREV_WHITE) | AVOID_LPASTE;
960 if (node->flags & NODE_BUILTIN)
962 builtin_macro (pfile, token);
963 token->flags = flags;
967 if (node->value.macro->disabled)
968 token->flags |= NO_EXPAND;
969 else if (enter_macro_context (pfile, node))
973 /* Don't interpret _Pragma within directives. The standard is
974 not clear on this, but to me this makes most sense. */
975 if (token->val.node != pfile->spec_nodes.n__Pragma
976 || pfile->state.in_directive)
979 /* Handle it, and loop back for another token. MI is cleared
980 since this token came from either the lexer or a macro. */
981 _cpp_do__Pragma (pfile);
985 save_lookahead_token (pfile, token);
988 /* Read each token in, until EOF. Directives are transparently
991 cpp_scan_buffer_nooutput (pfile, all_buffers)
996 cpp_buffer *buffer = all_buffers ? 0: pfile->buffer->prev;
1000 cpp_get_token (pfile, &token);
1001 while (token.type != CPP_EOF);
1002 while (cpp_pop_buffer (pfile) != buffer);
1005 /* Lookahead handling. */
1008 save_lookahead_token (pfile, token)
1010 const cpp_token *token;
1012 if (token->type != CPP_EOF)
1014 cpp_lookahead *la = pfile->la_write;
1015 cpp_token_with_pos *twp;
1017 if (la->count == la->cap)
1019 la->cap += la->cap + 8;
1020 la->tokens = (cpp_token_with_pos *)
1021 xrealloc (la->tokens, la->cap * sizeof (cpp_token_with_pos));
1024 twp = &la->tokens[la->count++];
1025 twp->token = *token;
1026 twp->pos = *cpp_get_line (pfile);
1031 take_lookahead_token (pfile, token)
1035 cpp_lookahead *la = pfile->la_read;
1036 cpp_token_with_pos *twp = &la->tokens[la->cur];
1038 *token = twp->token;
1039 pfile->lexer_pos = twp->pos;
1041 if (++la->cur == la->count)
1042 _cpp_release_lookahead (pfile);
1045 /* Moves the lookahead at the front of the read list to the free store. */
1047 _cpp_release_lookahead (pfile)
1050 cpp_lookahead *la = pfile->la_read;
1052 pfile->la_read = la->next;
1053 la->next = pfile->la_unused;
1054 pfile->la_unused = la;
1055 unlock_pools (pfile);
1058 /* Take a new lookahead from the free store, or allocate one if none. */
1059 static cpp_lookahead *
1060 alloc_lookahead (pfile)
1063 cpp_lookahead *la = pfile->la_unused;
1066 pfile->la_unused = la->next;
1069 la = xnew (cpp_lookahead);
1074 la->cur = la->count = 0;
1078 /* Free memory associated with a lookahead list. */
1084 free ((PTR) la->tokens);
1088 /* Free all the lookaheads of a cpp_reader. */
1090 _cpp_free_lookaheads (pfile)
1093 cpp_lookahead *la, *lan;
1096 free_lookahead (pfile->la_read);
1097 if (pfile->la_write)
1098 free_lookahead (pfile->la_write);
1100 for (la = pfile->la_unused; la; la = lan)
1103 free_lookahead (la);
1107 /* Allocate a lookahead and move it to the front of the write list. */
1109 cpp_start_lookahead (pfile)
1112 cpp_lookahead *la = alloc_lookahead (pfile);
1114 la->next = pfile->la_write;
1115 pfile->la_write = la;
1117 la->pos = *cpp_get_line (pfile);
1119 /* Don't allow memory pools to be re-used whilst we're reading ahead. */
1123 /* Stop reading ahead - either step back, or drop the read ahead. */
1125 cpp_stop_lookahead (pfile, drop)
1129 cpp_lookahead *la = pfile->la_write;
1131 pfile->la_write = la->next;
1132 la->next = pfile->la_read;
1133 pfile->la_read = la;
1135 if (drop || la->count == 0)
1136 _cpp_release_lookahead (pfile);
1138 pfile->lexer_pos = la->pos;
1141 /* Push a single token back to the front of the queue. Only to be
1142 used by cpplib, and only then when necessary. POS is the position
1143 to report for the preceding token. */
1145 _cpp_push_token (pfile, token, pos)
1147 const cpp_token *token;
1148 const cpp_lexer_pos *pos;
1150 cpp_start_lookahead (pfile);
1151 save_lookahead_token (pfile, token);
1152 cpp_stop_lookahead (pfile, 0);
1153 pfile->lexer_pos = *pos;
1156 /* #define directive parsing and handling. */
1158 /* Returns non-zero if a macro redefinition is trivial. */
1160 check_macro_redefinition (pfile, node, macro2)
1162 const cpp_hashnode *node;
1163 const cpp_macro *macro2;
1165 const cpp_macro *macro1;
1168 if (node->type != NT_MACRO || node->flags & NODE_BUILTIN)
1169 return ! pfile->done_initializing;
1171 macro1 = node->value.macro;
1173 /* The quick failures. */
1174 if (macro1->count != macro2->count
1175 || macro1->paramc != macro2->paramc
1176 || macro1->fun_like != macro2->fun_like
1177 || macro1->variadic != macro2->variadic)
1180 /* Check each token. */
1181 for (i = 0; i < macro1->count; i++)
1182 if (! _cpp_equiv_tokens (¯o1->expansion[i], ¯o2->expansion[i]))
1185 /* Check parameter spellings. */
1186 for (i = 0; i < macro1->paramc; i++)
1187 if (macro1->params[i] != macro2->params[i])
1193 /* Free the definition of hashnode H. */
1196 _cpp_free_definition (h)
1199 /* Macros and assertions no longer have anything to free. */
1201 /* Clear builtin flag in case of redefinition. */
1202 h->flags &= ~NODE_BUILTIN;
1206 save_parameter (pfile, macro, node)
1211 cpp_hashnode **dest;
1213 /* Constraint 6.10.3.6 - duplicate parameter names. */
1214 if (node->arg_index)
1216 cpp_error (pfile, "duplicate macro parameter \"%s\"", node->name);
1220 dest = ¯o->params[macro->paramc];
1222 /* Check we have room for the parameters. */
1223 if ((unsigned char *) (dest + 1) >= POOL_LIMIT (&pfile->macro_pool))
1225 _cpp_next_chunk (&pfile->macro_pool, sizeof (cpp_hashnode *),
1226 (unsigned char **) ¯o->params);
1227 dest = ¯o->params[macro->paramc];
1231 node->arg_index = ++macro->paramc;
1236 parse_params (pfile, macro)
1241 unsigned int prev_ident = 0;
1243 macro->params = (cpp_hashnode **) POOL_FRONT (&pfile->macro_pool);
1246 _cpp_lex_token (pfile, &token);
1251 cpp_error (pfile, "\"%s\" may not appear in macro parameter list",
1252 cpp_token_as_text (pfile, &token));
1258 cpp_error (pfile, "macro parameters must be comma-separated");
1263 if (save_parameter (pfile, macro, token.val.node))
1267 case CPP_CLOSE_PAREN:
1268 if (prev_ident || macro->paramc == 0)
1271 /* Fall through to pick up the error. */
1275 cpp_error (pfile, "parameter name missing");
1282 macro->variadic = 1;
1285 save_parameter (pfile, macro, pfile->spec_nodes.n__VA_ARGS__);
1286 pfile->state.va_args_ok = 1;
1287 if (! CPP_OPTION (pfile, c99) && CPP_OPTION (pfile, pedantic))
1289 "anonymous variadic macros were introduced in C99");
1291 else if (CPP_OPTION (pfile, pedantic))
1292 cpp_pedwarn (pfile, "ISO C does not permit named variadic macros");
1294 /* We're at the end, and just expect a closing parenthesis. */
1295 _cpp_lex_token (pfile, &token);
1296 if (token.type == CPP_CLOSE_PAREN)
1301 cpp_error (pfile, "missing ')' in macro parameter list");
1305 /* Success. Commit the parameter array. */
1306 POOL_COMMIT (&pfile->macro_pool,
1307 macro->paramc * sizeof (cpp_hashnode *));
1312 /* Lex a token from a macro's replacement list. Translate it to a
1313 CPP_MACRO_ARG if appropriate. */
1315 lex_expansion_token (pfile, macro)
1319 cpp_token *token = ¯o->expansion[macro->count];
1321 /* Check we have room for the token. */
1322 if ((unsigned char *) (token + 1) >= POOL_LIMIT (&pfile->macro_pool))
1324 _cpp_next_chunk (&pfile->macro_pool, sizeof (cpp_token),
1325 (unsigned char **) ¯o->expansion);
1326 token = ¯o->expansion[macro->count];
1330 _cpp_lex_token (pfile, token);
1332 /* Is this an argument? */
1333 if (token->type == CPP_NAME && token->val.node->arg_index)
1335 token->type = CPP_MACRO_ARG;
1336 token->val.arg_no = token->val.node->arg_index;
1338 else if (CPP_WTRADITIONAL (pfile) && macro->paramc > 0
1339 && (token->type == CPP_STRING || token->type == CPP_CHAR))
1340 check_trad_stringification (pfile, macro, &token->val.str);
1345 /* Parse a macro and save its expansion. Returns non-zero on success. */
1347 _cpp_create_definition (pfile, node)
1353 unsigned int i, ok = 1;
1355 macro = (cpp_macro *) _cpp_pool_alloc (&pfile->macro_pool,
1356 sizeof (cpp_macro));
1357 macro->file = pfile->buffer->nominal_fname;
1358 macro->line = pfile->directive_pos.line;
1361 macro->fun_like = 0;
1362 macro->variadic = 0;
1364 macro->expansion = (cpp_token *) POOL_FRONT (&pfile->macro_pool);
1366 /* Get the first token of the expansion (or the '(' of a
1367 function-like macro). */
1368 token = lex_expansion_token (pfile, macro);
1369 if (token->type == CPP_OPEN_PAREN && !(token->flags & PREV_WHITE))
1371 if (!(ok = parse_params (pfile, macro)))
1374 macro->fun_like = 1;
1375 /* Some of the pool may have been used for the parameter store. */
1376 macro->expansion = (cpp_token *) POOL_FRONT (&pfile->macro_pool);
1377 token = lex_expansion_token (pfile, macro);
1379 else if (token->type != CPP_EOF && !(token->flags & PREV_WHITE))
1380 cpp_pedwarn (pfile, "ISO C requires whitespace after the macro name");
1382 /* Setting it here means we don't catch leading comments. */
1383 pfile->state.save_comments = ! CPP_OPTION (pfile, discard_comments);
1387 /* Check the stringifying # constraint 6.10.3.2.1 of
1388 function-like macros when lexing the subsequent token. */
1389 if (macro->count > 1 && token[-1].type == CPP_HASH && macro->fun_like)
1391 if (token->type == CPP_MACRO_ARG)
1393 token->flags &= ~PREV_WHITE;
1394 token->flags |= STRINGIFY_ARG;
1395 token->flags |= token[-1].flags & PREV_WHITE;
1396 token[-1] = token[0];
1399 /* Let assembler get away with murder. */
1400 else if (CPP_OPTION (pfile, lang) != CLK_ASM)
1403 cpp_error (pfile, "'#' is not followed by a macro parameter");
1408 if (token->type == CPP_EOF)
1411 /* Paste operator constraint 6.10.3.3.1. */
1412 if (token->type == CPP_PASTE)
1414 /* Token-paste ##, can appear in both object-like and
1415 function-like macros, but not at the ends. */
1416 if (--macro->count > 0)
1417 token = lex_expansion_token (pfile, macro);
1419 if (macro->count == 0 || token->type == CPP_EOF)
1423 "'##' cannot appear at either end of a macro expansion");
1427 token[-1].flags |= PASTE_LEFT;
1428 /* Give it a PREV_WHITE for -dM etc. */
1429 token->flags |= PREV_WHITE;
1432 token = lex_expansion_token (pfile, macro);
1435 /* Don't count the CPP_EOF. */
1438 /* Clear the whitespace flag from the leading token. */
1439 macro->expansion[0].flags &= ~PREV_WHITE;
1441 /* Implement the macro-defined-to-itself optimisation. */
1442 macro->disabled = (macro->count == 1 && !macro->fun_like
1443 && macro->expansion[0].type == CPP_NAME
1444 && macro->expansion[0].val.node == node);
1446 /* Commit the memory. */
1447 POOL_COMMIT (&pfile->macro_pool, macro->count * sizeof (cpp_token));
1449 /* Redefinition of a macro is allowed if and only if the old and new
1450 definitions are the same. (6.10.3 paragraph 2). */
1451 if (node->type != NT_VOID)
1453 if (CPP_PEDANTIC (pfile)
1454 && !check_macro_redefinition (pfile, node, macro))
1456 cpp_pedwarn_with_line (pfile, pfile->directive_pos.line,
1457 pfile->directive_pos.col,
1458 "\"%s\" redefined", node->name);
1460 if (pfile->done_initializing && node->type == NT_MACRO
1461 && !(node->flags & NODE_BUILTIN))
1462 cpp_pedwarn_with_file_and_line (pfile,
1463 node->value.macro->file,
1464 node->value.macro->line, 1,
1465 "this is the location of the previous definition");
1467 _cpp_free_definition (node);
1470 /* Enter definition in hash table. */
1471 node->type = NT_MACRO;
1472 node->value.macro = macro;
1476 /* Stop the lexer accepting __VA_ARGS__. */
1477 pfile->state.va_args_ok = 0;
1479 /* Clear the fast argument lookup indices. */
1480 for (i = macro->paramc; i-- > 0; )
1481 macro->params[i]->arg_index = 0;
1486 /* Warn if a token in `string' matches one of the function macro
1487 arguments in `info'. This function assumes that the macro is a
1488 function macro and not an object macro. */
1490 check_trad_stringification (pfile, macro, string)
1492 const cpp_macro *macro;
1493 const cpp_string *string;
1495 unsigned int i, len;
1496 const U_CHAR *p, *q, *limit = string->text + string->len;
1498 /* Loop over the string. */
1499 for (p = string->text; p < limit; p = q)
1501 /* Find the start of an identifier. */
1502 while (p < limit && !is_idstart (*p))
1505 /* Find the end of the identifier. */
1507 while (q < limit && is_idchar (*q))
1512 /* Loop over the function macro arguments to see if the
1513 identifier inside the string matches one of them. */
1514 for (i = 0; i < macro->paramc; i++)
1516 const cpp_hashnode *node = macro->params[i];
1518 if (node->length == len && !memcmp (p, node->name, len))
1521 "macro argument \"%s\" would be stringified with -traditional.",
1529 /* Returns the expansion of a macro, in a format suitable to be read
1530 back in again, and therefore also for DWARF 2 debugging info.
1531 Caller is expected to generate the "#define NAME" bit. The
1532 returned text is temporary, and automatically freed later. */
1534 const unsigned char *
1535 cpp_macro_definition (pfile, node)
1537 const cpp_hashnode *node;
1539 unsigned int i, len;
1540 const cpp_macro *macro = node->value.macro;
1541 unsigned char *buffer;
1543 if (node->type != NT_MACRO || (node->flags & NODE_BUILTIN))
1545 cpp_ice (pfile, "invalid hash type %d in dump_definition", node->type);
1549 /* Calculate length. */
1551 if (macro->fun_like)
1553 len += 3; /* "()" plus possible final "." of ellipsis. */
1554 for (i = 0; i < macro->paramc; i++)
1555 len += macro->params[i]->length + 2; /* ", " */
1558 for (i = 0; i < macro->count; i++)
1560 cpp_token *token = ¯o->expansion[i];
1562 if (token->type == CPP_MACRO_ARG)
1563 len += macro->params[token->val.arg_no - 1]->length;
1565 len += cpp_token_len (token); /* Includes room for ' '. */
1566 if (token->flags & STRINGIFY_ARG)
1568 if (token->flags & PASTE_LEFT)
1569 len += 3; /* " ##" */
1572 if (len > pfile->macro_buffer_len)
1574 pfile->macro_buffer = (U_CHAR *) xrealloc (pfile->macro_buffer, len);
1575 pfile->macro_buffer_len = len;
1577 buffer = pfile->macro_buffer;
1579 /* Parameter names. */
1580 if (macro->fun_like)
1583 for (i = 0; i < macro->paramc; i++)
1585 cpp_hashnode *param = macro->params[i];
1587 if (param != pfile->spec_nodes.n__VA_ARGS__)
1589 memcpy (buffer, param->name, param->length);
1590 buffer += param->length;
1593 if (i + 1 < macro->paramc)
1594 *buffer++ = ',', *buffer++ = ' ';
1595 else if (macro->variadic)
1596 *buffer++ = '.', *buffer++ = '.', *buffer++ = '.';
1601 /* Expansion tokens. */
1605 for (i = 0; i < macro->count; i++)
1607 cpp_token *token = ¯o->expansion[i];
1609 if (token->flags & PREV_WHITE)
1611 if (token->flags & STRINGIFY_ARG)
1614 if (token->type == CPP_MACRO_ARG)
1616 len = macro->params[token->val.arg_no - 1]->length;
1617 memcpy (buffer, macro->params[token->val.arg_no - 1]->name, 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;