2 Copyright (C) 1986, 1987, 1989, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
3 1999, 2000 Free Software Foundation, Inc.
4 Contributed by Per Bothner, 1994-95.
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. */
31 /* Stack of conditionals currently in progress
32 (including both successful and failing conditionals). */
36 struct if_stack *next;
37 unsigned int lineno; /* line number where condition started */
38 unsigned int colno; /* and column */
39 int was_skipping; /* value of pfile->skipping before this if */
40 const cpp_hashnode *cmacro; /* macro name for #ifndef around entire file */
41 int type; /* type of last directive seen in this group */
44 /* Forward declarations. */
46 static void validate_else PARAMS ((cpp_reader *, const U_CHAR *));
47 static int parse_include PARAMS ((cpp_reader *, const U_CHAR *, int,
48 const U_CHAR **, unsigned int *,
50 static void push_conditional PARAMS ((cpp_reader *, int, int,
51 const cpp_hashnode *));
52 static int read_line_number PARAMS ((cpp_reader *, int *));
53 static int strtoul_for_line PARAMS ((const U_CHAR *, unsigned int,
55 static void do_diagnostic PARAMS ((cpp_reader *, enum error_type));
56 static const cpp_hashnode *
57 parse_ifdef PARAMS ((cpp_reader *, const U_CHAR *));
58 static const cpp_hashnode *
59 detect_if_not_defined PARAMS ((cpp_reader *));
61 get_define_node PARAMS ((cpp_reader *));
62 static void unwind_if_stack PARAMS ((cpp_reader *, cpp_buffer *));
64 /* This is the table of directive handlers. It is ordered by
65 frequency of occurrence; the numbers at the end are directive
66 counts from all the source code I have lying around (egcs and libc
67 CVS as of 1999-05-18, plus grub-0.5.91, linux-2.2.9, and
70 The entries with a dash and a name after the count are extensions,
71 of which all but #warning and #include_next are deprecated. The name
72 is where the extension appears to have come from. */
74 /* #sccs is not always recognized. */
76 # define SCCS_ENTRY D(sccs, T_SCCS, EXTENSION, 0)
78 # define SCCS_ENTRY /* nothing */
81 #define DIRECTIVE_TABLE \
82 D(define, T_DEFINE = 0, KANDR, COMMENTS | IN_I)/* 270554 */ \
83 D(include, T_INCLUDE, KANDR, EXPAND | INCL) /* 52262 */ \
84 D(endif, T_ENDIF, KANDR, COND) /* 45855 */ \
85 D(ifdef, T_IFDEF, KANDR, COND) /* 22000 */ \
86 D(if, T_IF, KANDR, COND | EXPAND) /* 18162 */ \
87 D(else, T_ELSE, KANDR, COND) /* 9863 */ \
88 D(ifndef, T_IFNDEF, KANDR, COND) /* 9675 */ \
89 D(undef, T_UNDEF, KANDR, IN_I) /* 4837 */ \
90 D(line, T_LINE, KANDR, EXPAND) /* 2465 */ \
91 D(elif, T_ELIF, KANDR, COND | EXPAND) /* 610 */ \
92 D(error, T_ERROR, STDC89, 0) /* 475 */ \
93 D(pragma, T_PRAGMA, STDC89, IN_I) /* 195 */ \
94 D(warning, T_WARNING, EXTENSION, 0) /* 22 GNU */ \
95 D(include_next, T_INCLUDE_NEXT, EXTENSION, EXPAND | INCL) /* 19 GNU */ \
96 D(ident, T_IDENT, EXTENSION, IN_I) /* 11 SVR4 */ \
97 D(import, T_IMPORT, EXTENSION, EXPAND | INCL) /* 0 ObjC */ \
98 D(assert, T_ASSERT, EXTENSION, 0) /* 0 SVR4 */ \
99 D(unassert, T_UNASSERT, EXTENSION, 0) /* 0 SVR4 */ \
100 SCCS_ENTRY /* 0 SVR2? */
102 /* Use the table to generate a series of prototypes, an enum for the
103 directive names, and an array of directive handlers. */
105 /* The directive-processing functions are declared to return int
106 instead of void, because some old compilers have trouble with
107 pointers to functions returning void. */
109 /* Don't invoke CONCAT2 with any whitespace or K&R cc will fail. */
110 #define D(name, t, o, f) static void CONCAT2(do_,name) PARAMS ((cpp_reader *));
114 #define D(n, tag, o, f) tag,
122 /* Don't invoke CONCAT2 with any whitespace or K&R cc will fail. */
123 #define D(name, t, origin, flags) \
124 { CONCAT2(do_,name), (const U_CHAR *) STRINGX(name), \
125 sizeof STRINGX(name) - 1, origin, flags },
126 static const struct directive dtable[] =
131 #undef DIRECTIVE_TABLE
133 /* Check if a token's name matches that of a known directive. Put in
134 this file to save exporting dtable and other unneeded information. */
135 const struct directive *
136 _cpp_check_directive (pfile, token)
138 const cpp_token *token;
142 if (token->type != CPP_NAME)
144 if (token->type == CPP_EOF && CPP_WTRADITIONAL (pfile)
145 && pfile->state.indented)
146 cpp_warning (pfile, "traditional C ignores #\\n with the # indented");
151 for (i = 0; i < N_DIRECTIVES; i++)
152 if (pfile->spec_nodes->dirs[i] == token->val.node)
155 if (i == N_DIRECTIVES)
158 /* We should lex headers correctly, regardless of whether we're
160 pfile->state.angled_headers = dtable[i].flags & INCL;
162 /* If we are rescanning preprocessed input, only directives tagged
163 with IN_I are honored, and the warnings below are suppressed. */
164 if (CPP_OPTION (pfile, preprocessed))
166 if (!dtable[i].flags & IN_I)
171 /* Traditionally, a directive is ignored unless its # is in
172 column 1. Therefore in code intended to work with K+R
173 compilers, directives added by C89 must have their #
174 indented, and directives present in traditional C must not.
175 This is true even of directives in skipped conditional
177 if (CPP_WTRADITIONAL (pfile))
179 if (pfile->state.indented && dtable[i].origin == KANDR)
181 "traditional C ignores #%s with the # indented",
184 else if (!pfile->state.indented && dtable[i].origin != KANDR)
186 "suggest hiding #%s from traditional C with an indented #",
190 /* If we are skipping a failed conditional group, all non-conditional
191 directives are ignored. */
192 if (pfile->skipping && !(dtable[i].flags & COND))
195 /* Issue -pedantic warnings for extended directives. */
196 if (CPP_PEDANTIC (pfile) && dtable[i].origin == EXTENSION)
197 cpp_pedwarn (pfile, "ISO C does not allow #%s", dtable[i].name);
200 /* Only flag to save comments if we process the directive. */
201 pfile->state.save_comments = (! CPP_OPTION (pfile, discard_comments)
202 && (dtable[i].flags & COMMENTS));
207 const struct directive *
208 _cpp_check_linemarker (pfile, token)
210 const cpp_token *token ATTRIBUTE_UNUSED;
212 /* # followed by a number is equivalent to #line. Do not recognize
213 this form in assembly language source files or skipped
214 conditional groups. Complain about this form if we're being
215 pedantic, but not if this is regurgitated input (preprocessed or
216 fed back in by the C++ frontend). */
217 if (pfile->skipping || CPP_OPTION (pfile, lang_asm))
220 if (CPP_PEDANTIC (pfile) && CPP_BUFFER (pfile)->inc
221 && ! CPP_OPTION (pfile, preprocessed))
222 cpp_pedwarn (pfile, "# followed by integer");
224 /* In -traditional mode, a directive is ignored unless its #
226 if (pfile->state.indented && CPP_WTRADITIONAL (pfile))
227 cpp_warning (pfile, "traditional C ignores #%s with the # indented",
228 dtable[T_LINE].name);
230 return &dtable[T_LINE];
233 static cpp_hashnode *
234 get_define_node (pfile)
237 const cpp_token *token;
239 /* Skip any -C comments. */
240 while ((token = _cpp_get_token (pfile))->type == CPP_COMMENT)
243 /* The token immediately after #define must be an identifier. That
244 identifier is not allowed to be "defined". See predefined macro
245 names (6.10.8.4). In C++, it is not allowed to be any of the
246 <iso646.h> macro names (which are keywords in C++) either. */
248 if (token->type != CPP_NAME)
250 if (token->type == CPP_DEFINED)
251 cpp_error_with_line (pfile, token->line, token->col,
252 "\"defined\" cannot be used as a macro name");
253 else if (token->flags & NAMED_OP)
254 cpp_error_with_line (pfile, token->line, token->col,
255 "\"%s\" cannot be used as a macro name in C++",
256 token->val.node->name);
258 cpp_error_with_line (pfile, token->line, token->col,
259 "macro names must be identifiers");
263 /* In Objective C, some keywords begin with '@', but general identifiers
264 do not, and you're not allowed to #define them. */
265 if (token->val.node->name[0] == '@')
267 cpp_error_with_line (pfile, token->line, token->col,
268 "\"%s\" cannot be used as a macro name",
269 token->val.node->name);
273 /* Check for poisoned identifiers now. */
274 if (token->val.node->type == T_POISON)
276 cpp_error_with_line (pfile, token->line, token->col,
277 "attempt to use poisoned \"%s\"",
278 token->val.node->name);
282 return token->val.node;
285 /* Process a #define command. */
292 if ((node = get_define_node (pfile)))
293 if (_cpp_create_definition (pfile, node))
294 if (pfile->cb.define)
295 (*pfile->cb.define) (pfile, node);
298 /* Remove the definition of a symbol from the symbol table. */
303 cpp_hashnode *node = get_define_node (pfile);
305 if (_cpp_get_token (pfile)->type != CPP_EOF)
306 cpp_pedwarn (pfile, "junk on line after #undef");
308 /* 6.10.3.5 paragraph 2: [#undef] is ignored if the specified identifier
309 is not currently defined as a macro name. */
310 if (node && node->type != T_VOID)
313 (*pfile->cb.undef) (pfile, node);
315 if (node->type != T_MACRO)
316 cpp_warning (pfile, "undefining \"%s\"", node->name);
318 _cpp_free_definition (node);
323 /* Handle #include and #import. */
326 parse_include (pfile, dir, trail, strp, lenp, abp)
334 const cpp_token *name = _cpp_get_token (pfile);
336 if (name->type != CPP_STRING && name->type != CPP_HEADER_NAME)
338 if (name->type == CPP_LESS)
339 name = _cpp_glue_header_name (pfile);
342 cpp_error (pfile, "#%s expects \"FILENAME\" or <FILENAME>", dir);
346 if (name->val.str.len == 0)
348 cpp_error (pfile, "empty file name in #%s", dir);
352 if (!trail && _cpp_get_token (pfile)->type != CPP_EOF)
353 cpp_error (pfile, "junk at end of #%s", dir);
355 *lenp = name->val.str.len;
356 *strp = name->val.str.text;
357 *abp = (name->type == CPP_HEADER_NAME);
359 if (pfile->cb.include)
360 (*pfile->cb.include) (pfile, dir, *strp, *lenp, *abp);
372 if (parse_include (pfile, dtable[T_INCLUDE].name, 0, &str, &len, &ab))
375 _cpp_execute_include (pfile, str, len, 0, 0, ab);
386 if (!pfile->import_warning && CPP_OPTION (pfile, warn_import))
388 pfile->import_warning = 1;
390 "#import is obsolete, use an #ifndef wrapper in the header file");
393 if (parse_include (pfile, dtable[T_IMPORT].name, 0, &str, &len, &ab))
396 _cpp_execute_include (pfile, str, len, 1, 0, ab);
400 do_include_next (pfile)
405 struct file_name_list *search_start = 0;
408 if (parse_include (pfile, dtable[T_INCLUDE_NEXT].name, 0, &str, &len, &ab))
411 /* For #include_next, skip in the search path past the dir in which
412 the current file was found. If this is the last directory in the
413 search path, don't include anything. If the current file was
414 specified with an absolute path, use the normal search logic. If
415 this is the primary source file, use the normal search logic and
416 generate a warning. */
417 if (CPP_PREV_BUFFER (CPP_BUFFER (pfile)))
419 if (CPP_BUFFER (pfile)->inc->foundhere)
421 search_start = CPP_BUFFER (pfile)->inc->foundhere->next;
427 cpp_warning (pfile, "#include_next in primary source file");
429 _cpp_execute_include (pfile, str, len, 0, search_start, ab);
432 /* Subroutine of do_line. Read next token from PFILE without adding it to
433 the output buffer. If it is a number between 1 and 4, store it in *NUM
434 and return 1; otherwise, return 0 and complain if we aren't at the end
438 read_line_number (pfile, num)
442 const cpp_token *tok = _cpp_get_token (pfile);
443 enum cpp_ttype type = tok->type;
444 const U_CHAR *p = tok->val.str.text;
445 unsigned int len = tok->val.str.len;
447 if (type == CPP_NUMBER && len == 1 && p[0] >= '1' && p[0] <= '4')
455 cpp_error (pfile, "invalid format #line");
460 /* Another subroutine of do_line. Convert a number in STR, of length
461 LEN, to binary; store it in NUMP, and return 0 if the number was
462 well-formed, 1 if not. Temporary, hopefully. */
464 strtoul_for_line (str, len, nump)
469 unsigned long reg = 0;
483 /* Interpret #line command.
484 Note that the filename string (if any) is treated as if it were an
485 include filename. That means no escape handling. */
491 cpp_buffer *ip = CPP_BUFFER (pfile);
492 unsigned long new_lineno, old_lineno;
493 /* C99 raised the minimum limit on #line numbers. */
494 unsigned int cap = CPP_OPTION (pfile, c99) ? 2147483647 : 32767;
495 int action_number = 0;
496 int enter = 0, leave = 0, rename = 0;
501 const cpp_token *tok;
503 tok = _cpp_get_token (pfile);
505 str = tok->val.str.text;
506 len = tok->val.str.len;
508 if (type != CPP_NUMBER || strtoul_for_line (str, len, &new_lineno))
510 cpp_error (pfile, "token after #line is not a positive integer");
514 if (CPP_PEDANTIC (pfile) && (new_lineno == 0 || new_lineno > cap))
515 cpp_pedwarn (pfile, "line number out of range");
517 old_lineno = ip->lineno;
518 ip->lineno = new_lineno;
519 tok = _cpp_get_token (pfile);
521 str = tok->val.str.text;
522 len = tok->val.str.len;
526 else if (type != CPP_STRING)
528 cpp_error (pfile, "second token after #line is not a string");
529 ip->lineno = old_lineno; /* malformed #line should have no effect */
533 fname = alloca (len + 1);
534 memcpy (fname, str, len);
537 if (strcmp (fname, ip->nominal_fname))
540 if (!strcmp (fname, ip->inc->name))
541 ip->nominal_fname = ip->inc->name;
543 ip->nominal_fname = _cpp_fake_include (pfile, fname);
546 if (read_line_number (pfile, &action_number) == 0)
549 if (CPP_PEDANTIC (pfile))
550 cpp_pedwarn (pfile, "garbage at end of #line");
552 if (action_number == 1)
555 cpp_make_system_header (pfile, ip, 0);
556 read_line_number (pfile, &action_number);
558 else if (action_number == 2)
561 cpp_make_system_header (pfile, ip, 0);
562 read_line_number (pfile, &action_number);
564 if (action_number == 3)
566 cpp_make_system_header (pfile, ip, 1);
567 read_line_number (pfile, &action_number);
569 if (action_number == 4)
571 cpp_make_system_header (pfile, ip, 2);
572 read_line_number (pfile, &action_number);
576 if (enter && pfile->cb.enter_file)
577 (*pfile->cb.enter_file) (pfile);
578 if (leave && pfile->cb.leave_file)
579 (*pfile->cb.leave_file) (pfile);
580 if (rename && pfile->cb.rename_file)
581 (*pfile->cb.rename_file) (pfile);
585 * Report a warning or error detected by the program we are
586 * processing. Use the directive's tokens in the error message.
590 do_diagnostic (pfile, code)
592 enum error_type code;
594 if (_cpp_begin_message (pfile, code, NULL, 0, 0))
596 cpp_output_list (pfile, stderr, &pfile->token_list,
597 pfile->first_directive_token);
606 do_diagnostic (pfile, ERROR);
613 do_diagnostic (pfile, WARNING);
616 /* Report program identification. */
622 const cpp_token *str = _cpp_get_token (pfile);
624 if (str->type == CPP_STRING && _cpp_get_token (pfile)->type == CPP_EOF)
627 (*pfile->cb.ident) (pfile, str->val.str.text, str->val.str.len);
631 cpp_error (pfile, "invalid #ident");
634 /* Pragmata handling. We handle some of these, and pass the rest on
635 to the front end. C99 defines three pragmas and says that no macro
636 expansion is to be performed on them; whether or not macro
637 expansion happens for other pragmas is implementation defined.
638 This implementation never macro-expands the text after #pragma.
640 We currently do not support the _Pragma operator. Support for that
641 has to be coordinated with the front end. Proposed implementation:
642 both #pragma blah blah and _Pragma("blah blah") become
643 __builtin_pragma(blah blah) and we teach the parser about that. */
645 /* Sub-handlers for the pragmas needing treatment here.
646 They return 1 if the token buffer is to be popped, 0 if not. */
649 struct pragma_entry *next;
654 void (*handler) PARAMS ((cpp_reader *));
655 struct pragma_entry *space;
660 cpp_register_pragma (pfile, space, name, handler)
664 void (*handler) PARAMS ((cpp_reader *));
666 struct pragma_entry **x, *new;
672 struct pragma_entry *p = pfile->pragmas;
673 len = strlen (space);
676 if (p->isnspace && p->len == len && !memcmp (p->name, space, len))
683 cpp_ice (pfile, "unknown #pragma namespace %s", space);
688 new = xnew (struct pragma_entry);
690 new->len = strlen (name);
692 new->u.handler = handler;
699 cpp_register_pragma_space (pfile, space)
703 struct pragma_entry *new;
704 const struct pragma_entry *p = pfile->pragmas;
705 size_t len = strlen (space);
709 if (p->isnspace && p->len == len && !memcmp (p->name, space, len))
710 /* Multiple different callers are allowed to register the same
716 new = xnew (struct pragma_entry);
722 new->next = pfile->pragmas;
723 pfile->pragmas = new;
726 static void do_pragma_once PARAMS ((cpp_reader *));
727 static void do_pragma_poison PARAMS ((cpp_reader *));
728 static void do_pragma_system_header PARAMS ((cpp_reader *));
729 static void do_pragma_dependency PARAMS ((cpp_reader *));
732 _cpp_init_internal_pragmas (pfile)
736 cpp_register_pragma (pfile, 0, "poison", do_pragma_poison);
737 cpp_register_pragma (pfile, 0, "once", do_pragma_once);
740 cpp_register_pragma_space (pfile, "GCC");
742 cpp_register_pragma (pfile, "GCC", "poison", do_pragma_poison);
743 cpp_register_pragma (pfile, "GCC", "system_header", do_pragma_system_header);
744 cpp_register_pragma (pfile, "GCC", "dependency", do_pragma_dependency);
751 const struct pragma_entry *p;
752 const cpp_token *tok;
753 const cpp_hashnode *node;
760 tok = _cpp_get_token (pfile);
761 if (tok->type == CPP_EOF)
764 if (tok->type != CPP_NAME)
766 cpp_error (pfile, "malformed #pragma directive");
770 node = tok->val.node;
775 if (strlen (p->name) == len && !memcmp (p->name, name, len))
784 (*p->u.handler) (pfile);
791 if (pfile->cb.def_pragma)
792 (*pfile->cb.def_pragma) (pfile);
796 do_pragma_once (pfile)
799 cpp_buffer *ip = CPP_BUFFER (pfile);
801 /* Allow #pragma once in system headers, since that's not the user's
803 cpp_warning (pfile, "#pragma once is obsolete");
805 if (CPP_PREV_BUFFER (ip) == NULL)
806 cpp_warning (pfile, "#pragma once outside include file");
808 ip->inc->cmacro = NEVER_REREAD;
812 do_pragma_poison (pfile)
815 /* Poison these symbols so that all subsequent usage produces an
817 const cpp_token *tok;
822 tok = _cpp_get_token (pfile);
823 if (tok->type == CPP_EOF)
825 if (tok->type != CPP_NAME)
827 cpp_error (pfile, "invalid #pragma poison directive");
832 if (hp->type == T_POISON)
833 ; /* It is allowed to poison the same identifier twice. */
836 if (hp->type != T_VOID)
837 cpp_warning (pfile, "poisoning existing macro \"%s\"", hp->name);
838 _cpp_free_definition (hp);
843 if (pfile->cb.poison)
844 (*pfile->cb.poison) (pfile);
847 /* Mark the current header as a system header. This will suppress
848 some categories of warnings (notably those from -pedantic). It is
849 intended for use in system libraries that cannot be implemented in
850 conforming C, but cannot be certain that their headers appear in a
851 system include directory. To prevent abuse, it is rejected in the
852 primary source file. */
854 do_pragma_system_header (pfile)
857 cpp_buffer *ip = CPP_BUFFER (pfile);
858 if (CPP_PREV_BUFFER (ip) == NULL)
859 cpp_warning (pfile, "#pragma system_header outside include file");
861 cpp_make_system_header (pfile, ip, 1);
864 /* Check the modified date of the current include file against a specified
865 file. Issue a diagnostic, if the specified file is newer. We use this to
866 determine if a fixed header should be refixed. */
868 do_pragma_dependency (pfile)
876 if (parse_include (pfile, U"pragma dependency", 1, &name, &len, &ab))
879 left = ab ? '<' : '"';
880 right = ab ? '>' : '"';
882 ordering = _cpp_compare_file_date (pfile, name, len, ab);
884 cpp_warning (pfile, "cannot find source %c%s%c", left, name, right);
885 else if (ordering > 0)
887 const cpp_token *msg = _cpp_get_token (pfile);
889 cpp_warning (pfile, "current file is older than %c%.*s%c",
890 left, (int)len, name, right);
891 if (msg->type != CPP_EOF
892 && _cpp_begin_message (pfile, WARNING, NULL, msg->line, msg->col))
894 cpp_output_list (pfile, stderr, &pfile->token_list, msg);
900 /* Just ignore #sccs, on systems where we define it at all. */
901 #ifdef SCCS_DIRECTIVE
904 cpp_reader *pfile ATTRIBUTE_UNUSED;
909 /* We've found an `#if' directive. If the only thing before it in
910 this file is white space, and if it is of the form
911 `#if ! defined SYMBOL', then SYMBOL is a possible controlling macro
912 for inclusion of this file. (See redundant_include_p in cppfiles.c
913 for an explanation of controlling macros.) If so, return the
914 hash node for SYMBOL. Otherwise, return NULL. */
916 static const cpp_hashnode *
917 detect_if_not_defined (pfile)
920 const cpp_token *token;
921 cpp_hashnode *cmacro = 0;
923 /* We are guaranteed that tokens are consecutive and end in CPP_EOF. */
924 token = pfile->first_directive_token + 2;
926 if (token->type != CPP_NOT)
930 if (token->type != CPP_DEFINED)
934 if (token->type == CPP_OPEN_PAREN)
937 if (token->type != CPP_NAME)
940 cmacro = token->val.node;
942 if (token[-1].type == CPP_OPEN_PAREN)
945 if (token->type != CPP_CLOSE_PAREN)
950 if (token->type != CPP_EOF)
956 /* Parse an #ifdef or #ifndef directive. Returns the hash node of the
957 macro being tested, and issues various error messages. */
959 static const cpp_hashnode *
960 parse_ifdef (pfile, name)
965 const cpp_hashnode *node = 0;
967 const cpp_token *token = _cpp_get_token (pfile);
971 cpp_pedwarn (pfile, "#%s with no argument", name);
972 else if (type != CPP_NAME)
973 cpp_pedwarn (pfile, "#%s with invalid argument", name);
974 else if (_cpp_get_token (pfile)->type != CPP_EOF)
975 cpp_pedwarn (pfile, "garbage at end of #%s", name);
977 if (type == CPP_NAME)
978 node = token->val.node;
979 if (node && node->type == T_POISON)
981 cpp_error (pfile, "attempt to use poisoned identifier \"%s\"",
989 /* #ifdef is dead simple. */
995 const cpp_hashnode *node = 0;
997 if (! pfile->skipping)
998 node = parse_ifdef (pfile, dtable[T_IFDEF].name);
1000 push_conditional (pfile, !(node && node->type != T_VOID), T_IFDEF, 0);
1003 /* #ifndef is a tad more complex, because we need to check for a
1004 no-reinclusion wrapper. */
1010 int start_of_file = 0;
1011 const cpp_hashnode *node = 0;
1013 if (! pfile->skipping)
1015 start_of_file = (pfile->token_list.flags & BEG_OF_FILE);
1016 node = parse_ifdef (pfile, dtable[T_IFNDEF].name);
1019 push_conditional (pfile, node && node->type != T_VOID,
1020 T_IFNDEF, start_of_file ? node : 0);
1023 /* #if is straightforward; just call _cpp_parse_expr, then conditional_skip.
1024 Also, check for a reinclude preventer of the form #if !defined (MACRO). */
1030 const cpp_hashnode *cmacro = 0;
1033 if (! pfile->skipping)
1035 if (pfile->token_list.flags & BEG_OF_FILE)
1036 cmacro = detect_if_not_defined (pfile);
1037 value = _cpp_parse_expr (pfile);
1039 push_conditional (pfile, value == 0, T_IF, cmacro);
1042 /* #else flips pfile->skipping and continues without changing
1043 if_stack; this is so that the error message for missing #endif's
1044 etc. will point to the original #if. */
1050 struct if_stack *ifs = CPP_BUFFER (pfile)->if_stack;
1051 validate_else (pfile, dtable[T_ELSE].name);
1055 cpp_error (pfile, "#else without #if");
1058 if (ifs->type == T_ELSE)
1060 cpp_error (pfile, "#else after #else");
1061 cpp_error_with_line (pfile, ifs->lineno, ifs->colno,
1062 "the conditional began here");
1065 /* #ifndef can't have its special treatment for containing the whole file
1066 if it has a #else clause. */
1069 if (! ifs->was_skipping)
1071 /* If pfile->skipping is 2, one of the blocks in an #if/#elif/... chain
1072 succeeded, so we mustn't do the else block. */
1073 if (pfile->skipping < 2)
1074 pfile->skipping = ! pfile->skipping;
1079 * handle a #elif directive by not changing if_stack either.
1080 * see the comment above do_else.
1087 struct if_stack *ifs = CPP_BUFFER (pfile)->if_stack;
1091 cpp_error (pfile, "#elif without #if");
1094 if (ifs->type == T_ELSE)
1096 cpp_error (pfile, "#elif after #else");
1097 cpp_error_with_line (pfile, ifs->lineno, ifs->colno,
1098 "the conditional began here");
1102 if (ifs->was_skipping)
1103 return; /* Don't evaluate a nested #if */
1105 if (pfile->skipping != 1)
1107 pfile->skipping = 2; /* one block succeeded, so don't do any others */
1111 pfile->skipping = ! _cpp_parse_expr (pfile);
1114 /* #endif pops the if stack and resets pfile->skipping. */
1120 struct if_stack *ifs = CPP_BUFFER (pfile)->if_stack;
1122 validate_else (pfile, dtable[T_ENDIF].name);
1125 cpp_error (pfile, "#endif without #if");
1128 CPP_BUFFER (pfile)->if_stack = ifs->next;
1129 pfile->skipping = ifs->was_skipping;
1130 pfile->potential_control_macro = ifs->cmacro;
1131 obstack_free (pfile->buffer_ob, ifs);
1136 /* Push an if_stack entry and set pfile->skipping accordingly.
1137 If this is a #ifndef starting at the beginning of a file,
1138 CMACRO is the macro name tested by the #ifndef. */
1141 push_conditional (pfile, skip, type, cmacro)
1145 const cpp_hashnode *cmacro;
1147 struct if_stack *ifs;
1149 ifs = xobnew (pfile->buffer_ob, struct if_stack);
1150 ifs->lineno = _cpp_get_line (pfile, &ifs->colno);
1151 ifs->next = CPP_BUFFER (pfile)->if_stack;
1152 ifs->cmacro = cmacro;
1153 ifs->was_skipping = pfile->skipping;
1156 if (!pfile->skipping)
1157 pfile->skipping = skip;
1159 CPP_BUFFER (pfile)->if_stack = ifs;
1162 /* Issue -pedantic warning for text which is not a comment following
1163 an #else or #endif. */
1166 validate_else (pfile, directive)
1168 const U_CHAR *directive;
1170 if (CPP_PEDANTIC (pfile) && _cpp_get_token (pfile)->type != CPP_EOF)
1171 cpp_pedwarn (pfile, "ISO C forbids text after #%s", directive);
1174 /* Called when we reach the end of a file. Walk back up the
1175 conditional stack till we reach its level at entry to this file,
1176 issuing error messages. Then force skipping off. */
1178 unwind_if_stack (pfile, pbuf)
1182 struct if_stack *ifs, *nifs;
1184 for (ifs = pbuf->if_stack; ifs; ifs = nifs)
1186 cpp_error_with_line (pfile, ifs->lineno, ifs->colno, "unterminated #%s",
1187 dtable[ifs->type].name);
1189 /* No need to free - they'll all go away with the buffer. */
1191 pfile->skipping = 0;
1194 /* Parses an assertion, returning a pointer to the hash node of the
1195 predicate, or 0 on error. If an answer was supplied, it is
1196 allocated and placed in ANSWERP, otherwise it is set to 0. We use
1197 _cpp_get_raw_token, since we cannot assume tokens are consecutive
1198 in a #if statement (we may be in a macro), and we don't want to
1201 _cpp_parse_assertion (pfile, answerp)
1203 struct answer **answerp;
1205 struct answer *answer = 0;
1208 const cpp_token *token, *predicate;
1209 const struct directive *d = pfile->token_list.directive;
1210 unsigned int len = 0;
1212 predicate = _cpp_get_raw_token (pfile);
1213 if (predicate->type == CPP_EOF)
1215 cpp_error (pfile, "assertion without predicate");
1218 else if (predicate->type != CPP_NAME)
1220 cpp_error (pfile, "predicate must be an identifier");
1224 token = _cpp_get_raw_token (pfile);
1225 if (token->type != CPP_OPEN_PAREN)
1227 /* #unassert and #if are OK without predicate. */
1228 if (d == &dtable[T_UNASSERT])
1230 if (token->type == CPP_EOF)
1233 else if (d != &dtable[T_ASSERT])
1235 _cpp_push_token (pfile, token);
1238 cpp_error (pfile, "missing '(' after predicate");
1242 /* Allocate a struct answer, and copy the answer to it. */
1243 answer = (struct answer *) xmalloc (sizeof (struct answer));
1244 list = &answer->list;
1245 _cpp_init_toklist (list, 1); /* Empty. */
1251 token = _cpp_get_raw_token (pfile);
1253 if (token->type == CPP_EOF)
1255 cpp_error (pfile, "missing ')' to complete answer");
1258 if (token->type == CPP_CLOSE_PAREN)
1261 /* Copy the token. */
1262 _cpp_expand_token_space (list, 1);
1263 dest = &list->tokens[list->tokens_used++];
1266 if (TOKEN_SPELL (token) == SPELL_STRING)
1268 _cpp_expand_name_space (list, token->val.str.len);
1269 dest->val.str.text = list->namebuf + list->name_used;
1270 memcpy (list->namebuf + list->name_used,
1271 token->val.str.text, token->val.str.len);
1272 list->name_used += token->val.str.len;
1276 if (list->tokens_used == 0)
1278 cpp_error (pfile, "predicate's answer is empty");
1282 /* Drop whitespace at start. */
1283 list->tokens[0].flags &= ~PREV_WHITE;
1285 if ((d == &dtable[T_ASSERT] || d == &dtable[T_UNASSERT])
1286 && token[1].type != CPP_EOF)
1288 cpp_error (pfile, "junk at end of assertion");
1294 len = predicate->val.node->length;
1295 sym = alloca (len + 1);
1297 /* Prefix '#' to get it out of macro namespace. */
1299 memcpy (sym + 1, predicate->val.node->name, len);
1300 return cpp_lookup (pfile, sym, len + 1);
1303 FREE_ANSWER (answer);
1307 /* Returns a pointer to the pointer to the answer in the answer chain,
1308 or a pointer to NULL if the answer is not in the chain. */
1310 _cpp_find_answer (node, candidate)
1312 const cpp_toklist *candidate;
1314 struct answer **result;
1316 for (result = &node->value.answers; *result; result = &(*result)->next)
1317 if (_cpp_equiv_toklists (&(*result)->list, candidate))
1327 struct answer *new_answer;
1330 node = _cpp_parse_assertion (pfile, &new_answer);
1333 new_answer->next = 0;
1334 new_answer->list.file = pfile->token_list.file;
1336 if (node->type == T_ASSERTION)
1338 if (*_cpp_find_answer (node, &new_answer->list))
1340 new_answer->next = node->value.answers;
1342 node->type = T_ASSERTION;
1343 node->value.answers = new_answer;
1348 cpp_warning (pfile, "\"%s\" re-asserted", node->name + 1);
1349 FREE_ANSWER (new_answer);
1357 struct answer *answer, *temp;
1359 node = _cpp_parse_assertion (pfile, &answer);
1362 /* It isn't an error to #unassert something that isn't asserted. */
1363 if (node->type == T_ASSERTION)
1367 struct answer **p = _cpp_find_answer (node, &answer->list);
1375 if (node->value.answers == 0)
1376 node->type = T_VOID;
1379 _cpp_free_definition (node);
1383 FREE_ANSWER (answer);
1387 /* These are for -D, -U, -A. */
1389 /* Process the string STR as if it appeared as the body of a #define.
1390 If STR is just an identifier, define it with value 1.
1391 If STR has anything after the identifier, then it should
1392 be identifier=definition. */
1395 cpp_define (pfile, str)
1402 p = strchr (str, '=');
1403 /* Copy the entire option so we can modify it.
1404 Change the first "=" in the string to a space. If there is none,
1405 tack " 1" on the end. Then add a newline and a NUL. */
1409 count = strlen (str) + 2;
1410 buf = (char *) alloca (count);
1411 memcpy (buf, str, count - 2);
1413 buf[count - 2] = '\n';
1414 buf[count - 1] = '\0';
1418 count = strlen (str) + 4;
1419 buf = (char *) alloca (count);
1420 memcpy (buf, str, count - 4);
1421 strcpy (&buf[count-4], " 1\n");
1424 _cpp_run_directive (pfile, &dtable[T_DEFINE], buf, count - 1, 0);
1427 /* Slight variant of the above for use by initialize_builtins, which (a)
1428 knows how to set up the buffer itself, (b) needs a different "filename"
1431 _cpp_define_builtin (pfile, str)
1435 _cpp_run_directive (pfile, &dtable[T_DEFINE],
1440 /* Process MACRO as if it appeared as the body of an #undef. */
1442 cpp_undef (pfile, macro)
1446 _cpp_run_directive (pfile, &dtable[T_UNDEF], macro, strlen (macro), 0);
1449 /* Process the string STR as if it appeared as the body of a #assert. */
1451 cpp_assert (pfile, str)
1455 _cpp_run_directive (pfile, &dtable[T_ASSERT], str, strlen (str), 0);
1458 /* Process STR as if it appeared as the body of an #unassert. */
1460 cpp_unassert (pfile, str)
1464 _cpp_run_directive (pfile, &dtable[T_UNASSERT], str, strlen (str), 0);
1467 /* Determine whether the identifier ID, of length LEN, is a defined macro. */
1469 cpp_defined (pfile, id, len)
1474 cpp_hashnode *hp = cpp_lookup (pfile, id, len);
1475 if (hp->type == T_POISON)
1477 cpp_error (pfile, "attempt to use poisoned \"%s\"", hp->name);
1480 return (hp->type != T_VOID);
1483 /* Allocate a new cpp_buffer for PFILE, and push it on the input buffer stack.
1484 If BUFFER != NULL, then use the LENGTH characters in BUFFER
1485 as the new input buffer.
1486 Return the new buffer, or NULL on failure. */
1489 cpp_push_buffer (pfile, buffer, length)
1491 const U_CHAR *buffer;
1494 cpp_buffer *buf = CPP_BUFFER (pfile);
1496 if (++pfile->buffer_stack_depth == CPP_STACK_MAX)
1498 cpp_fatal (pfile, "#include nested too deep");
1501 if (pfile->cur_context > 0)
1503 cpp_ice (pfile, "buffer pushed with contexts stacked");
1504 _cpp_skip_rest_of_line (pfile);
1507 new = xobnew (pfile->buffer_ob, cpp_buffer);
1508 memset (new, 0, sizeof (cpp_buffer));
1510 new->line_base = new->buf = new->cur = buffer;
1511 new->rlimit = buffer + length;
1514 /* No read ahead or extra char initially. */
1515 new->read_ahead = EOF;
1516 new->extra_char = EOF;
1518 CPP_BUFFER (pfile) = new;
1523 cpp_pop_buffer (pfile)
1527 cpp_buffer *buf = CPP_BUFFER (pfile);
1529 unwind_if_stack (pfile, buf);
1530 wfb = (buf->inc != 0);
1532 _cpp_pop_file_buffer (pfile, buf);
1534 CPP_BUFFER (pfile) = CPP_PREV_BUFFER (buf);
1535 obstack_free (pfile->buffer_ob, buf);
1536 pfile->buffer_stack_depth--;
1538 if (wfb && pfile->cb.leave_file && CPP_BUFFER (pfile))
1539 (*pfile->cb.leave_file) (pfile);
1541 return CPP_BUFFER (pfile);
1544 #define obstack_chunk_alloc xmalloc
1545 #define obstack_chunk_free free
1546 #define DSC(x) U x, sizeof x - 1
1548 _cpp_init_stacks (pfile)
1552 struct spec_nodes *s;
1554 pfile->buffer_ob = xnew (struct obstack);
1555 obstack_init (pfile->buffer_ob);
1557 /* Perhaps not the ideal place to put this. */
1558 pfile->spec_nodes = s = xnew (struct spec_nodes);
1559 s->n_L = cpp_lookup (pfile, DSC("L"));
1560 s->n__STRICT_ANSI__ = cpp_lookup (pfile, DSC("__STRICT_ANSI__"));
1561 s->n__CHAR_UNSIGNED__ = cpp_lookup (pfile, DSC("__CHAR_UNSIGNED__"));
1562 s->n__VA_ARGS__ = cpp_lookup (pfile, DSC("__VA_ARGS__"));
1563 for (i = 0; i < N_DIRECTIVES; i++)
1564 s->dirs[i] = cpp_lookup (pfile, dtable[i].name, dtable[i].length);
1568 _cpp_cleanup_stacks (pfile)
1571 obstack_free (pfile->buffer_ob, 0);
1572 free (pfile->buffer_ob);