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,
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, bol)
138 const cpp_token *token;
143 for (i = 0; i < N_DIRECTIVES; i++)
144 if (pfile->spec_nodes->dirs[i] == token->val.node)
146 /* If we are rescanning preprocessed input, only directives
147 tagged with IN_I are to be honored, and the warnings below
149 if (CPP_OPTION (pfile, preprocessed))
151 if (dtable[i].flags & IN_I)
156 /* In -traditional mode, a directive is ignored unless its #
157 is in column 1. In code intended to work with K+R compilers,
158 therefore, directives added by C89 must have their # indented,
159 and directives present in traditional C must not. This is true
160 even of directives in skipped conditional blocks. */
161 if (CPP_WTRADITIONAL (pfile))
163 if (!bol && dtable[i].origin == KANDR)
165 "traditional C ignores #%s with the # indented",
168 if (bol && dtable[i].origin != KANDR)
170 "suggest hiding #%s from traditional C with an indented #",
174 /* If we are skipping a failed conditional group, all non-conditional
175 directives are ignored. */
176 if (pfile->skipping && !(dtable[i].flags & COND))
179 /* Issue -pedantic warnings for extended directives. */
180 if (CPP_PEDANTIC (pfile) && dtable[i].origin == EXTENSION)
181 cpp_pedwarn (pfile, "ISO C does not allow #%s", dtable[i].name);
189 const struct directive *
190 _cpp_check_linemarker (pfile, token, bol)
192 const cpp_token *token ATTRIBUTE_UNUSED;
195 /* # followed by a number is equivalent to #line. Do not recognize
196 this form in assembly language source files or skipped
197 conditional groups. Complain about this form if we're being
198 pedantic, but not if this is regurgitated input (preprocessed or
199 fed back in by the C++ frontend). */
200 if (pfile->skipping || CPP_OPTION (pfile, lang_asm))
203 if (CPP_PEDANTIC (pfile) && CPP_BUFFER (pfile)->inc
204 && ! CPP_OPTION (pfile, preprocessed))
205 cpp_pedwarn (pfile, "# followed by integer");
207 /* In -traditional mode, a directive is ignored unless its #
209 if (!bol && CPP_WTRADITIONAL (pfile))
210 cpp_warning (pfile, "traditional C ignores #%s with the # indented",
211 dtable[T_LINE].name);
213 return &dtable[T_LINE];
216 static cpp_hashnode *
217 get_define_node (pfile)
220 const cpp_token *token;
222 /* Skip any -C comments. */
223 while ((token = _cpp_get_token (pfile))->type == CPP_COMMENT)
226 /* The token immediately after #define must be an identifier. That
227 identifier is not allowed to be "defined". See predefined macro
228 names (6.10.8.4). In C++, it is not allowed to be any of the
229 <iso646.h> macro names (which are keywords in C++) either. */
231 if (token->type != CPP_NAME)
233 if (token->type == CPP_DEFINED)
234 cpp_error_with_line (pfile, token->line, token->col,
235 "\"defined\" cannot be used as a macro name");
236 else if (token->flags & NAMED_OP)
237 cpp_error_with_line (pfile, token->line, token->col,
238 "\"%s\" cannot be used as a macro name in C++",
239 token->val.node->name);
241 cpp_error_with_line (pfile, token->line, token->col,
242 "macro names must be identifiers");
246 /* In Objective C, some keywords begin with '@', but general identifiers
247 do not, and you're not allowed to #define them. */
248 if (token->val.node->name[0] == '@')
250 cpp_error_with_line (pfile, token->line, token->col,
251 "\"%s\" cannot be used as a macro name",
252 token->val.node->name);
256 /* Check for poisoned identifiers now. */
257 if (token->val.node->type == T_POISON)
259 cpp_error_with_line (pfile, token->line, token->col,
260 "attempt to use poisoned \"%s\"",
261 token->val.node->name);
265 return token->val.node;
268 /* Process a #define command. */
275 if ((node = get_define_node (pfile)))
276 if (_cpp_create_definition (pfile, node))
277 if (pfile->cb.define)
278 (*pfile->cb.define) (pfile, node);
281 /* Remove the definition of a symbol from the symbol table. */
286 cpp_hashnode *node = get_define_node (pfile);
288 if (_cpp_get_token (pfile)->type != CPP_EOF)
289 cpp_pedwarn (pfile, "junk on line after #undef");
291 /* 6.10.3.5 paragraph 2: [#undef] is ignored if the specified identifier
292 is not currently defined as a macro name. */
293 if (node && node->type != T_VOID)
296 (*pfile->cb.undef) (pfile, node);
298 if (node->type != T_MACRO)
299 cpp_warning (pfile, "undefining \"%s\"", node->name);
301 _cpp_free_definition (node);
306 /* Handle #include and #import. */
309 parse_include (pfile, dir, trail, strp, lenp, abp)
317 const cpp_token *name = _cpp_get_token (pfile);
319 if (name->type != CPP_STRING && name->type != CPP_HEADER_NAME)
321 if (name->type == CPP_LESS)
322 name = _cpp_glue_header_name (pfile);
325 cpp_error (pfile, "#%s expects \"FILENAME\" or <FILENAME>", dir);
329 if (name->val.str.len == 0)
331 cpp_error (pfile, "empty file name in #%s", dir);
335 if (!trail && _cpp_get_token (pfile)->type != CPP_EOF)
336 cpp_error (pfile, "junk at end of #%s", dir);
338 *lenp = name->val.str.len;
339 *strp = name->val.str.text;
340 *abp = (name->type == CPP_HEADER_NAME);
342 if (pfile->cb.include)
343 (*pfile->cb.include) (pfile, dir, *strp, *lenp, *abp);
355 if (parse_include (pfile, dtable[T_INCLUDE].name, 0, &str, &len, &ab))
358 _cpp_execute_include (pfile, str, len, 0, 0, ab);
369 if (CPP_OPTION (pfile, warn_import)
370 && !CPP_IN_SYSTEM_HEADER (pfile) && !pfile->import_warning)
372 pfile->import_warning = 1;
374 "#import is obsolete, use an #ifndef wrapper in the header file");
377 if (parse_include (pfile, dtable[T_IMPORT].name, 0, &str, &len, &ab))
380 _cpp_execute_include (pfile, str, len, 1, 0, ab);
384 do_include_next (pfile)
389 struct file_name_list *search_start = 0;
392 if (parse_include (pfile, dtable[T_INCLUDE_NEXT].name, 0, &str, &len, &ab))
395 /* For #include_next, skip in the search path past the dir in which
396 the current file was found. If this is the last directory in the
397 search path, don't include anything. If the current file was
398 specified with an absolute path, use the normal search logic. If
399 this is the primary source file, use the normal search logic and
400 generate a warning. */
401 if (CPP_PREV_BUFFER (CPP_BUFFER (pfile)))
403 if (CPP_BUFFER (pfile)->inc->foundhere)
405 search_start = CPP_BUFFER (pfile)->inc->foundhere->next;
411 cpp_warning (pfile, "#include_next in primary source file");
413 _cpp_execute_include (pfile, str, len, 0, search_start, ab);
416 /* Subroutine of do_line. Read next token from PFILE without adding it to
417 the output buffer. If it is a number between 1 and 4, store it in *NUM
418 and return 1; otherwise, return 0 and complain if we aren't at the end
422 read_line_number (pfile, num)
426 const cpp_token *tok = _cpp_get_token (pfile);
427 enum cpp_ttype type = tok->type;
428 const U_CHAR *p = tok->val.str.text;
429 unsigned int len = tok->val.str.len;
431 if (type == CPP_NUMBER && len == 1 && p[0] >= '1' && p[0] <= '4')
439 cpp_error (pfile, "invalid format #line");
444 /* Another subroutine of do_line. Convert a number in STR, of length
445 LEN, to binary; store it in NUMP, and return 0 if the number was
446 well-formed, 1 if not. Temporary, hopefully. */
448 strtoul_for_line (str, len, nump)
453 unsigned long reg = 0;
467 /* Interpret #line command.
468 Note that the filename string (if any) is treated as if it were an
469 include filename. That means no escape handling. */
475 cpp_buffer *ip = CPP_BUFFER (pfile);
476 unsigned long new_lineno, old_lineno;
477 /* C99 raised the minimum limit on #line numbers. */
478 unsigned int cap = CPP_OPTION (pfile, c99) ? 2147483647 : 32767;
479 int action_number = 0;
480 int enter = 0, leave = 0, rename = 0;
485 const cpp_token *tok;
487 tok = _cpp_get_token (pfile);
489 str = tok->val.str.text;
490 len = tok->val.str.len;
492 if (type != CPP_NUMBER || strtoul_for_line (str, len, &new_lineno))
494 cpp_error (pfile, "token after #line is not a positive integer");
498 if (CPP_PEDANTIC (pfile) && (new_lineno == 0 || new_lineno > cap))
499 cpp_pedwarn (pfile, "line number out of range");
501 old_lineno = ip->lineno;
502 ip->lineno = new_lineno;
503 tok = _cpp_get_token (pfile);
505 str = tok->val.str.text;
506 len = tok->val.str.len;
510 else if (type != CPP_STRING)
512 cpp_error (pfile, "second token after #line is not a string");
513 ip->lineno = old_lineno; /* malformed #line should have no effect */
517 fname = alloca (len + 1);
518 memcpy (fname, str, len);
521 if (strcmp (fname, ip->nominal_fname))
524 if (!strcmp (fname, ip->inc->name))
525 ip->nominal_fname = ip->inc->name;
527 ip->nominal_fname = _cpp_fake_include (pfile, fname);
530 if (read_line_number (pfile, &action_number) == 0)
533 if (CPP_PEDANTIC (pfile))
534 cpp_pedwarn (pfile, "garbage at end of #line");
536 if (action_number == 1)
539 cpp_make_system_header (pfile, ip, 0);
540 read_line_number (pfile, &action_number);
542 else if (action_number == 2)
545 cpp_make_system_header (pfile, ip, 0);
546 read_line_number (pfile, &action_number);
548 if (action_number == 3)
550 cpp_make_system_header (pfile, ip, 1);
551 read_line_number (pfile, &action_number);
553 if (action_number == 4)
555 cpp_make_system_header (pfile, ip, 2);
556 read_line_number (pfile, &action_number);
560 if (enter && pfile->cb.enter_file)
561 (*pfile->cb.enter_file) (pfile);
562 if (leave && pfile->cb.leave_file)
563 (*pfile->cb.leave_file) (pfile);
564 if (rename && pfile->cb.rename_file)
565 (*pfile->cb.rename_file) (pfile);
569 * Report an error detected by the program we are processing.
570 * Use the text of the line in the error message.
571 * (We use error because it prints the filename & line#.)
578 if (_cpp_begin_message (pfile, ERROR, NULL, 0, 0))
580 cpp_output_list (pfile, stderr, &pfile->token_list,
581 pfile->first_directive_token);
587 * Report a warning detected by the program we are processing.
588 * Use the text of the line in the warning message, then continue.
595 if (_cpp_begin_message (pfile, WARNING, NULL, 0, 0))
597 cpp_output_list (pfile, stderr, &pfile->token_list,
598 pfile->first_directive_token);
603 /* Report program identification. */
609 const cpp_token *str = _cpp_get_token (pfile);
611 if (str->type == CPP_STRING && _cpp_get_token (pfile)->type == CPP_EOF)
614 (*pfile->cb.ident) (pfile, str->val.str.text, str->val.str.len);
618 cpp_error (pfile, "invalid #ident");
621 /* Pragmata handling. We handle some of these, and pass the rest on
622 to the front end. C99 defines three pragmas and says that no macro
623 expansion is to be performed on them; whether or not macro
624 expansion happens for other pragmas is implementation defined.
625 This implementation never macro-expands the text after #pragma.
627 We currently do not support the _Pragma operator. Support for that
628 has to be coordinated with the front end. Proposed implementation:
629 both #pragma blah blah and _Pragma("blah blah") become
630 __builtin_pragma(blah blah) and we teach the parser about that. */
632 /* Sub-handlers for the pragmas needing treatment here.
633 They return 1 if the token buffer is to be popped, 0 if not. */
636 struct pragma_entry *next;
641 void (*handler) PARAMS ((cpp_reader *));
642 struct pragma_entry *space;
647 cpp_register_pragma (pfile, space, name, handler)
651 void (*handler) PARAMS ((cpp_reader *));
653 struct pragma_entry **x, *new;
659 struct pragma_entry *p = pfile->pragmas;
660 len = strlen (space);
663 if (p->isnspace && p->len == len && !memcmp (p->name, space, len))
670 cpp_ice (pfile, "unknown #pragma namespace %s", space);
675 new = xnew (struct pragma_entry);
677 new->len = strlen (name);
679 new->u.handler = handler;
686 cpp_register_pragma_space (pfile, space)
690 struct pragma_entry *new;
691 const struct pragma_entry *p = pfile->pragmas;
692 size_t len = strlen (space);
696 if (p->isnspace && p->len == len && !memcmp (p->name, space, len))
697 /* Multiple different callers are allowed to register the same
703 new = xnew (struct pragma_entry);
709 new->next = pfile->pragmas;
710 pfile->pragmas = new;
713 static void do_pragma_once PARAMS ((cpp_reader *));
714 static void do_pragma_poison PARAMS ((cpp_reader *));
715 static void do_pragma_system_header PARAMS ((cpp_reader *));
716 static void do_pragma_dependency PARAMS ((cpp_reader *));
719 _cpp_init_internal_pragmas (pfile)
723 cpp_register_pragma (pfile, 0, "poison", do_pragma_poison);
724 cpp_register_pragma (pfile, 0, "once", do_pragma_once);
727 cpp_register_pragma_space (pfile, "GCC");
729 cpp_register_pragma (pfile, "GCC", "poison", do_pragma_poison);
730 cpp_register_pragma (pfile, "GCC", "system_header", do_pragma_system_header);
731 cpp_register_pragma (pfile, "GCC", "dependency", do_pragma_dependency);
738 const struct pragma_entry *p;
739 const cpp_token *tok;
740 const cpp_hashnode *node;
747 tok = _cpp_get_token (pfile);
748 if (tok->type == CPP_EOF)
751 if (tok->type != CPP_NAME)
753 cpp_error (pfile, "malformed #pragma directive");
757 node = tok->val.node;
762 if (strlen (p->name) == len && !memcmp (p->name, name, len))
771 (*p->u.handler) (pfile);
778 if (pfile->cb.def_pragma)
779 (*pfile->cb.def_pragma) (pfile);
783 do_pragma_once (pfile)
786 cpp_buffer *ip = CPP_BUFFER (pfile);
788 /* Allow #pragma once in system headers, since that's not the user's
790 if (!CPP_IN_SYSTEM_HEADER (pfile))
791 cpp_warning (pfile, "#pragma once is obsolete");
793 if (CPP_PREV_BUFFER (ip) == NULL)
794 cpp_warning (pfile, "#pragma once outside include file");
796 ip->inc->cmacro = NEVER_REREAD;
800 do_pragma_poison (pfile)
803 /* Poison these symbols so that all subsequent usage produces an
805 const cpp_token *tok;
810 tok = _cpp_get_token (pfile);
811 if (tok->type == CPP_EOF)
813 if (tok->type != CPP_NAME)
815 cpp_error (pfile, "invalid #pragma poison directive");
820 if (hp->type == T_POISON)
821 ; /* It is allowed to poison the same identifier twice. */
824 if (hp->type != T_VOID)
825 cpp_warning (pfile, "poisoning existing macro \"%s\"", hp->name);
826 _cpp_free_definition (hp);
831 if (pfile->cb.poison)
832 (*pfile->cb.poison) (pfile);
835 /* Mark the current header as a system header. This will suppress
836 some categories of warnings (notably those from -pedantic). It is
837 intended for use in system libraries that cannot be implemented in
838 conforming C, but cannot be certain that their headers appear in a
839 system include directory. To prevent abuse, it is rejected in the
840 primary source file. */
842 do_pragma_system_header (pfile)
845 cpp_buffer *ip = CPP_BUFFER (pfile);
846 if (CPP_PREV_BUFFER (ip) == NULL)
847 cpp_warning (pfile, "#pragma system_header outside include file");
849 cpp_make_system_header (pfile, ip, 1);
852 /* Check the modified date of the current include file against a specified
853 file. Issue a diagnostic, if the specified file is newer. We use this to
854 determine if a fixed header should be refixed. */
856 do_pragma_dependency (pfile)
864 if (parse_include (pfile, U"pragma dependency", 1, &name, &len, &ab))
867 left = ab ? '<' : '"';
868 right = ab ? '>' : '"';
870 ordering = _cpp_compare_file_date (pfile, name, len, ab);
872 cpp_warning (pfile, "cannot find source %c%s%c", left, name, right);
873 else if (ordering > 0)
875 const cpp_token *msg = _cpp_get_token (pfile);
877 cpp_warning (pfile, "current file is older than %c%.*s%c",
878 left, (int)len, name, right);
879 if (msg->type != CPP_EOF
880 && _cpp_begin_message (pfile, WARNING, NULL, msg->line, msg->col))
882 cpp_output_list (pfile, stderr, &pfile->token_list, msg);
888 /* Just ignore #sccs, on systems where we define it at all. */
889 #ifdef SCCS_DIRECTIVE
892 cpp_reader *pfile ATTRIBUTE_UNUSED;
897 /* We've found an `#if' directive. If the only thing before it in
898 this file is white space, and if it is of the form
899 `#if ! defined SYMBOL', then SYMBOL is a possible controlling macro
900 for inclusion of this file. (See redundant_include_p in cppfiles.c
901 for an explanation of controlling macros.) If so, return the
902 hash node for SYMBOL. Otherwise, return NULL. */
904 static const cpp_hashnode *
905 detect_if_not_defined (pfile)
908 const cpp_token *token;
909 cpp_hashnode *cmacro = 0;
911 /* We are guaranteed that tokens are consecutive and end in CPP_EOF. */
912 token = pfile->first_directive_token + 2;
914 if (token->type != CPP_NOT)
918 if (token->type != CPP_DEFINED)
922 if (token->type == CPP_OPEN_PAREN)
925 if (token->type != CPP_NAME)
928 cmacro = token->val.node;
930 if (token[-1].type == CPP_OPEN_PAREN)
933 if (token->type != CPP_CLOSE_PAREN)
938 if (token->type != CPP_EOF)
944 /* Parse an #ifdef or #ifndef directive. Returns the hash node of the
945 macro being tested, and issues various error messages. */
947 static const cpp_hashnode *
948 parse_ifdef (pfile, name)
953 const cpp_hashnode *node = 0;
955 const cpp_token *token = _cpp_get_token (pfile);
959 cpp_pedwarn (pfile, "#%s with no argument", name);
960 else if (type != CPP_NAME)
961 cpp_pedwarn (pfile, "#%s with invalid argument", name);
962 else if (_cpp_get_token (pfile)->type != CPP_EOF)
963 cpp_pedwarn (pfile, "garbage at end of #%s", name);
965 if (type == CPP_NAME)
966 node = token->val.node;
967 if (node && node->type == T_POISON)
969 cpp_error (pfile, "attempt to use poisoned identifier \"%s\"",
977 /* #ifdef is dead simple. */
983 const cpp_hashnode *node = 0;
985 if (! pfile->skipping)
986 node = parse_ifdef (pfile, dtable[T_IFDEF].name);
988 push_conditional (pfile, !(node && node->type != T_VOID), T_IFDEF, 0);
991 /* #ifndef is a tad more complex, because we need to check for a
992 no-reinclusion wrapper. */
998 int start_of_file = 0;
999 const cpp_hashnode *node = 0;
1001 if (! pfile->skipping)
1003 start_of_file = (pfile->token_list.flags & BEG_OF_FILE);
1004 node = parse_ifdef (pfile, dtable[T_IFNDEF].name);
1007 push_conditional (pfile, node && node->type != T_VOID,
1008 T_IFNDEF, start_of_file ? node : 0);
1011 /* #if is straightforward; just call _cpp_parse_expr, then conditional_skip.
1012 Also, check for a reinclude preventer of the form #if !defined (MACRO). */
1018 const cpp_hashnode *cmacro = 0;
1021 if (! pfile->skipping)
1023 if (pfile->token_list.flags & BEG_OF_FILE)
1024 cmacro = detect_if_not_defined (pfile);
1025 value = _cpp_parse_expr (pfile);
1027 push_conditional (pfile, value == 0, T_IF, cmacro);
1030 /* #else flips pfile->skipping and continues without changing
1031 if_stack; this is so that the error message for missing #endif's
1032 etc. will point to the original #if. */
1038 struct if_stack *ifs = CPP_BUFFER (pfile)->if_stack;
1039 validate_else (pfile, dtable[T_ELSE].name);
1043 cpp_error (pfile, "#else without #if");
1046 if (ifs->type == T_ELSE)
1048 cpp_error (pfile, "#else after #else");
1049 cpp_error_with_line (pfile, ifs->lineno, ifs->colno,
1050 "the conditional began here");
1053 /* #ifndef can't have its special treatment for containing the whole file
1054 if it has a #else clause. */
1057 if (! ifs->was_skipping)
1059 /* If pfile->skipping is 2, one of the blocks in an #if/#elif/... chain
1060 succeeded, so we mustn't do the else block. */
1061 if (pfile->skipping < 2)
1062 pfile->skipping = ! pfile->skipping;
1067 * handle a #elif directive by not changing if_stack either.
1068 * see the comment above do_else.
1075 struct if_stack *ifs = CPP_BUFFER (pfile)->if_stack;
1079 cpp_error (pfile, "#elif without #if");
1082 if (ifs->type == T_ELSE)
1084 cpp_error (pfile, "#elif after #else");
1085 cpp_error_with_line (pfile, ifs->lineno, ifs->colno,
1086 "the conditional began here");
1090 if (ifs->was_skipping)
1091 return; /* Don't evaluate a nested #if */
1093 if (pfile->skipping != 1)
1095 pfile->skipping = 2; /* one block succeeded, so don't do any others */
1099 pfile->skipping = ! _cpp_parse_expr (pfile);
1102 /* #endif pops the if stack and resets pfile->skipping. */
1108 struct if_stack *ifs = CPP_BUFFER (pfile)->if_stack;
1110 validate_else (pfile, dtable[T_ENDIF].name);
1113 cpp_error (pfile, "#endif without #if");
1116 CPP_BUFFER (pfile)->if_stack = ifs->next;
1117 pfile->skipping = ifs->was_skipping;
1118 pfile->potential_control_macro = ifs->cmacro;
1119 obstack_free (pfile->buffer_ob, ifs);
1124 /* Push an if_stack entry and set pfile->skipping accordingly.
1125 If this is a #ifndef starting at the beginning of a file,
1126 CMACRO is the macro name tested by the #ifndef. */
1129 push_conditional (pfile, skip, type, cmacro)
1133 const cpp_hashnode *cmacro;
1135 struct if_stack *ifs;
1137 ifs = xobnew (pfile->buffer_ob, struct if_stack);
1138 ifs->lineno = _cpp_get_line (pfile, &ifs->colno);
1139 ifs->next = CPP_BUFFER (pfile)->if_stack;
1140 ifs->cmacro = cmacro;
1141 ifs->was_skipping = pfile->skipping;
1144 if (!pfile->skipping)
1145 pfile->skipping = skip;
1147 CPP_BUFFER (pfile)->if_stack = ifs;
1150 /* Issue -pedantic warning for text which is not a comment following
1151 an #else or #endif. */
1154 validate_else (pfile, directive)
1156 const U_CHAR *directive;
1158 if (CPP_PEDANTIC (pfile) && _cpp_get_token (pfile)->type != CPP_EOF)
1159 cpp_pedwarn (pfile, "ISO C forbids text after #%s", directive);
1162 /* Called when we reach the end of a file. Walk back up the
1163 conditional stack till we reach its level at entry to this file,
1164 issuing error messages. Then force skipping off. */
1166 unwind_if_stack (pfile, pbuf)
1170 struct if_stack *ifs, *nifs;
1172 for (ifs = pbuf->if_stack; ifs; ifs = nifs)
1174 cpp_error_with_line (pfile, ifs->lineno, ifs->colno, "unterminated #%s",
1175 dtable[ifs->type].name);
1177 /* No need to free - they'll all go away with the buffer. */
1179 pfile->skipping = 0;
1182 /* Parses an assertion, returning a pointer to the hash node of the
1183 predicate, or 0 on error. If an answer was supplied, it is
1184 allocated and placed in ANSWERP, otherwise it is set to 0. We use
1185 _cpp_get_raw_token, since we cannot assume tokens are consecutive
1186 in a #if statement (we may be in a macro), and we don't want to
1189 _cpp_parse_assertion (pfile, answerp)
1191 struct answer **answerp;
1193 struct answer *answer = 0;
1196 const cpp_token *token, *predicate;
1197 const struct directive *d = pfile->token_list.directive;
1198 unsigned int len = 0;
1200 predicate = _cpp_get_raw_token (pfile);
1201 if (predicate->type == CPP_EOF)
1203 cpp_error (pfile, "assertion without predicate");
1206 else if (predicate->type != CPP_NAME)
1208 cpp_error (pfile, "predicate must be an identifier");
1212 token = _cpp_get_raw_token (pfile);
1213 if (token->type != CPP_OPEN_PAREN)
1215 /* #unassert and #if are OK without predicate. */
1216 if (d == &dtable[T_UNASSERT])
1218 if (token->type == CPP_EOF)
1221 else if (d != &dtable[T_ASSERT])
1223 _cpp_push_token (pfile, token);
1226 cpp_error (pfile, "missing '(' after predicate");
1230 /* Allocate a struct answer, and copy the answer to it. */
1231 answer = (struct answer *) xmalloc (sizeof (struct answer));
1232 list = &answer->list;
1233 _cpp_init_toklist (list, NO_DUMMY_TOKEN);
1239 token = _cpp_get_raw_token (pfile);
1241 if (token->type == CPP_EOF)
1243 cpp_error (pfile, "missing ')' to complete answer");
1246 if (token->type == CPP_CLOSE_PAREN)
1249 /* Copy the token. */
1250 _cpp_expand_token_space (list, 1);
1251 dest = &list->tokens[list->tokens_used++];
1254 if (TOKEN_SPELL (token) == SPELL_STRING)
1256 _cpp_expand_name_space (list, token->val.str.len);
1257 dest->val.str.text = list->namebuf + list->name_used;
1258 memcpy (list->namebuf + list->name_used,
1259 token->val.str.text, token->val.str.len);
1260 list->name_used += token->val.str.len;
1264 if (list->tokens_used == 0)
1266 cpp_error (pfile, "predicate's answer is empty");
1270 /* Drop whitespace at start. */
1271 list->tokens[0].flags &= ~PREV_WHITE;
1273 if ((d == &dtable[T_ASSERT] || d == &dtable[T_UNASSERT])
1274 && token[1].type != CPP_EOF)
1276 cpp_error (pfile, "junk at end of assertion");
1282 len = predicate->val.node->length;
1283 sym = alloca (len + 1);
1285 /* Prefix '#' to get it out of macro namespace. */
1287 memcpy (sym + 1, predicate->val.node->name, len);
1288 return cpp_lookup (pfile, sym, len + 1);
1291 FREE_ANSWER (answer);
1295 /* Returns a pointer to the pointer to the answer in the answer chain,
1296 or a pointer to NULL if the answer is not in the chain. */
1298 _cpp_find_answer (node, candidate)
1300 const cpp_toklist *candidate;
1302 struct answer **result;
1304 for (result = &node->value.answers; *result; result = &(*result)->next)
1305 if (_cpp_equiv_toklists (&(*result)->list, candidate))
1315 struct answer *new_answer;
1318 node = _cpp_parse_assertion (pfile, &new_answer);
1321 new_answer->next = 0;
1322 new_answer->list.line = pfile->token_list.line;
1323 new_answer->list.file = pfile->token_list.file;
1325 if (node->type == T_ASSERTION)
1327 if (*_cpp_find_answer (node, &new_answer->list))
1329 new_answer->next = node->value.answers;
1331 node->type = T_ASSERTION;
1332 node->value.answers = new_answer;
1337 cpp_warning (pfile, "\"%s\" re-asserted", node->name + 1);
1338 FREE_ANSWER (new_answer);
1346 struct answer *answer, *temp;
1348 node = _cpp_parse_assertion (pfile, &answer);
1351 /* It isn't an error to #unassert something that isn't asserted. */
1352 if (node->type == T_ASSERTION)
1356 struct answer **p = _cpp_find_answer (node, &answer->list);
1364 if (node->value.answers == 0)
1365 node->type = T_VOID;
1368 _cpp_free_definition (node);
1372 FREE_ANSWER (answer);
1376 /* These are for -D, -U, -A. */
1378 /* Process the string STR as if it appeared as the body of a #define.
1379 If STR is just an identifier, define it with value 1.
1380 If STR has anything after the identifier, then it should
1381 be identifier=definition. */
1384 cpp_define (pfile, str)
1391 p = strchr (str, '=');
1392 /* Copy the entire option so we can modify it.
1393 Change the first "=" in the string to a space. If there is none,
1394 tack " 1" on the end. Then add a newline and a NUL. */
1398 count = strlen (str) + 2;
1399 buf = (char *) alloca (count);
1400 memcpy (buf, str, count - 2);
1402 buf[count - 2] = '\n';
1403 buf[count - 1] = '\0';
1407 count = strlen (str) + 4;
1408 buf = (char *) alloca (count);
1409 memcpy (buf, str, count - 4);
1410 strcpy (&buf[count-4], " 1\n");
1413 _cpp_run_directive (pfile, &dtable[T_DEFINE], buf, count - 1);
1416 /* Process MACRO as if it appeared as the body of an #undef. */
1418 cpp_undef (pfile, macro)
1422 _cpp_run_directive (pfile, &dtable[T_UNDEF], macro, strlen (macro));
1425 /* Process the string STR as if it appeared as the body of a #assert. */
1427 cpp_assert (pfile, str)
1431 _cpp_run_directive (pfile, &dtable[T_ASSERT], str, strlen (str));
1434 /* Process STR as if it appeared as the body of an #unassert. */
1436 cpp_unassert (pfile, str)
1440 _cpp_run_directive (pfile, &dtable[T_UNASSERT], str, strlen (str));
1443 /* Determine whether the identifier ID, of length LEN, is a defined macro. */
1445 cpp_defined (pfile, id, len)
1450 cpp_hashnode *hp = cpp_lookup (pfile, id, len);
1451 if (hp->type == T_POISON)
1453 cpp_error (pfile, "attempt to use poisoned \"%s\"", hp->name);
1456 return (hp->type != T_VOID);
1459 /* Allocate a new cpp_buffer for PFILE, and push it on the input buffer stack.
1460 If BUFFER != NULL, then use the LENGTH characters in BUFFER
1461 as the new input buffer.
1462 Return the new buffer, or NULL on failure. */
1465 cpp_push_buffer (pfile, buffer, length)
1467 const U_CHAR *buffer;
1470 cpp_buffer *buf = CPP_BUFFER (pfile);
1472 if (++pfile->buffer_stack_depth == CPP_STACK_MAX)
1474 cpp_fatal (pfile, "#include nested too deep");
1477 if (pfile->cur_context > 0)
1479 cpp_ice (pfile, "buffer pushed with contexts stacked");
1480 _cpp_skip_rest_of_line (pfile);
1483 new = xobnew (pfile->buffer_ob, cpp_buffer);
1484 memset (new, 0, sizeof (cpp_buffer));
1486 new->line_base = new->buf = new->cur = buffer;
1487 new->rlimit = buffer + length;
1490 CPP_BUFFER (pfile) = new;
1495 cpp_pop_buffer (pfile)
1499 cpp_buffer *buf = CPP_BUFFER (pfile);
1501 unwind_if_stack (pfile, buf);
1502 wfb = (buf->inc != 0);
1504 _cpp_pop_file_buffer (pfile, buf);
1506 CPP_BUFFER (pfile) = CPP_PREV_BUFFER (buf);
1507 obstack_free (pfile->buffer_ob, buf);
1508 pfile->buffer_stack_depth--;
1510 if (wfb && pfile->cb.leave_file && CPP_BUFFER (pfile))
1511 (*pfile->cb.leave_file) (pfile);
1513 return CPP_BUFFER (pfile);
1516 #define obstack_chunk_alloc xmalloc
1517 #define obstack_chunk_free free
1518 #define DSC(x) U x, sizeof x - 1
1520 _cpp_init_stacks (pfile)
1524 struct spec_nodes *s;
1526 pfile->buffer_ob = xnew (struct obstack);
1527 obstack_init (pfile->buffer_ob);
1529 /* Perhaps not the ideal place to put this. */
1530 pfile->spec_nodes = s = xnew (struct spec_nodes);
1531 s->n_L = cpp_lookup (pfile, DSC("L"));
1532 s->n__STRICT_ANSI__ = cpp_lookup (pfile, DSC("__STRICT_ANSI__"));
1533 s->n__CHAR_UNSIGNED__ = cpp_lookup (pfile, DSC("__CHAR_UNSIGNED__"));
1534 s->n__VA_ARGS__ = cpp_lookup (pfile, DSC("__VA_ARGS__"));
1535 for (i = 0; i < N_DIRECTIVES; i++)
1536 s->dirs[i] = cpp_lookup (pfile, dtable[i].name, dtable[i].length);
1540 _cpp_cleanup_stacks (pfile)
1543 obstack_free (pfile->buffer_ob, 0);
1544 free (pfile->buffer_ob);