1 /* CPP Library. (Directive handling.)
2 Copyright (C) 1986, 1987, 1989, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
3 1999, 2000, 2001 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. */
30 /* Chained list of answers to an assertion. */
38 /* Stack of conditionals currently in progress
39 (including both successful and failing conditionals). */
43 struct if_stack *next;
44 cpp_lexer_pos pos; /* line and column where condition started */
45 const cpp_hashnode *mi_cmacro;/* macro name for #ifndef around entire file */
46 bool skip_elses; /* Can future #else / #elif be skipped? */
47 bool was_skipping; /* If were skipping on entry. */
48 int type; /* Most recent conditional, for diagnostics. */
51 /* Values for the origin field of struct directive. KANDR directives
52 come from traditional (K&R) C. STDC89 directives come from the
53 1989 C standard. EXTENSION directives are extensions. */
58 /* Values for the flags field of struct directive. COND indicates a
59 conditional; IF_COND an opening conditional. INCL means to treat
60 "..." and <...> as q-char and h-char sequences respectively. IN_I
61 means this directive should be handled even if -fpreprocessed is in
62 effect (these are the directives with callback hooks). */
64 #define IF_COND (1 << 1)
68 /* Defines one #-directive, including how to handle it. */
69 typedef void (*directive_handler) PARAMS ((cpp_reader *));
70 typedef struct directive directive;
73 directive_handler handler; /* Function to handle directive. */
74 const U_CHAR *name; /* Name of directive. */
75 unsigned short length; /* Length of name. */
76 unsigned char origin; /* Origin of directive. */
77 unsigned char flags; /* Flags describing this directive. */
80 /* Forward declarations. */
82 static void skip_rest_of_line PARAMS ((cpp_reader *));
83 static void check_eol PARAMS ((cpp_reader *));
84 static void start_directive PARAMS ((cpp_reader *));
85 static void end_directive PARAMS ((cpp_reader *, int));
86 static void run_directive PARAMS ((cpp_reader *, int,
88 const char *, size_t));
89 static int glue_header_name PARAMS ((cpp_reader *, cpp_token *));
90 static int parse_include PARAMS ((cpp_reader *, cpp_token *));
91 static void push_conditional PARAMS ((cpp_reader *, int, int,
92 const cpp_hashnode *));
93 static unsigned int read_flag PARAMS ((cpp_reader *, unsigned int));
94 static int strtoul_for_line PARAMS ((const U_CHAR *, unsigned int,
96 static void do_diagnostic PARAMS ((cpp_reader *, enum error_type, int));
97 static cpp_hashnode *lex_macro_node PARAMS ((cpp_reader *));
98 static void do_include_common PARAMS ((cpp_reader *, enum include_type));
99 static void do_pragma_once PARAMS ((cpp_reader *));
100 static void do_pragma_poison PARAMS ((cpp_reader *));
101 static void do_pragma_system_header PARAMS ((cpp_reader *));
102 static void do_pragma_dependency PARAMS ((cpp_reader *));
103 static int get__Pragma_string PARAMS ((cpp_reader *, cpp_token *));
104 static unsigned char *destringize PARAMS ((const cpp_string *,
106 static int parse_answer PARAMS ((cpp_reader *, struct answer **, int));
107 static cpp_hashnode *parse_assertion PARAMS ((cpp_reader *, struct answer **,
109 static struct answer ** find_answer PARAMS ((cpp_hashnode *,
110 const struct answer *));
111 static void handle_assertion PARAMS ((cpp_reader *, const char *, int));
113 /* This is the table of directive handlers. It is ordered by
114 frequency of occurrence; the numbers at the end are directive
115 counts from all the source code I have lying around (egcs and libc
116 CVS as of 1999-05-18, plus grub-0.5.91, linux-2.2.9, and
117 pcmcia-cs-3.0.9). This is no longer important as directive lookup
118 is now O(1). All extensions other than #warning and #include_next
119 are deprecated. The name is where the extension appears to have
122 #define DIRECTIVE_TABLE \
123 D(define, T_DEFINE = 0, KANDR, IN_I) /* 270554 */ \
124 D(include, T_INCLUDE, KANDR, INCL) /* 52262 */ \
125 D(endif, T_ENDIF, KANDR, COND) /* 45855 */ \
126 D(ifdef, T_IFDEF, KANDR, COND | IF_COND) /* 22000 */ \
127 D(if, T_IF, KANDR, COND | IF_COND) /* 18162 */ \
128 D(else, T_ELSE, KANDR, COND) /* 9863 */ \
129 D(ifndef, T_IFNDEF, KANDR, COND | IF_COND) /* 9675 */ \
130 D(undef, T_UNDEF, KANDR, IN_I) /* 4837 */ \
131 D(line, T_LINE, KANDR, IN_I) /* 2465 */ \
132 D(elif, T_ELIF, STDC89, COND) /* 610 */ \
133 D(error, T_ERROR, STDC89, 0) /* 475 */ \
134 D(pragma, T_PRAGMA, STDC89, IN_I) /* 195 */ \
135 D(warning, T_WARNING, EXTENSION, 0) /* 22 */ \
136 D(include_next, T_INCLUDE_NEXT, EXTENSION, INCL) /* 19 */ \
137 D(ident, T_IDENT, EXTENSION, IN_I) /* 11 */ \
138 D(import, T_IMPORT, EXTENSION, INCL) /* 0 ObjC */ \
139 D(assert, T_ASSERT, EXTENSION, 0) /* 0 SVR4 */ \
140 D(unassert, T_UNASSERT, EXTENSION, 0) /* 0 SVR4 */ \
141 SCCS_ENTRY /* 0 SVR4? */
143 /* #sccs is not always recognized. */
144 #ifdef SCCS_DIRECTIVE
145 # define SCCS_ENTRY D(sccs, T_SCCS, EXTENSION, 0)
147 # define SCCS_ENTRY /* nothing */
150 /* Use the table to generate a series of prototypes, an enum for the
151 directive names, and an array of directive handlers. */
153 /* The directive-processing functions are declared to return int
154 instead of void, because some old compilers have trouble with
155 pointers to functions returning void. */
157 /* Don't invoke CONCAT2 with any whitespace or K&R cc will fail. */
158 #define D(name, t, o, f) static void CONCAT2(do_,name) PARAMS ((cpp_reader *));
162 #define D(n, tag, o, f) tag,
170 /* Don't invoke CONCAT2 with any whitespace or K&R cc will fail. */
171 #define D(name, t, origin, flags) \
172 { CONCAT2(do_,name), (const U_CHAR *) STRINGX(name), \
173 sizeof STRINGX(name) - 1, origin, flags },
174 static const directive dtable[] =
179 #undef DIRECTIVE_TABLE
181 #define SEEN_EOL() (pfile->lexer_pos.output_line > pfile->line)
183 /* Skip any remaining tokens in a directive. */
185 skip_rest_of_line (pfile)
190 /* Discard all input lookaheads. */
191 while (pfile->la_read)
192 _cpp_release_lookahead (pfile);
194 /* Discard all stacked contexts. */
195 while (pfile->context != &pfile->base_context)
196 _cpp_pop_context (pfile);
198 /* Sweep up all tokens remaining on the line. */
199 while (! SEEN_EOL ())
200 _cpp_lex_token (pfile, &token);
203 /* Ensure there are no stray tokens at the end of a directive. */
212 _cpp_lex_token (pfile, &token);
213 if (token.type != CPP_EOF)
214 cpp_pedwarn (pfile, "extra tokens at end of #%s directive",
215 pfile->directive->name);
219 /* Called when entering a directive, _Pragma or command-line directive. */
221 start_directive (pfile)
224 /* Setup in-directive state. */
225 pfile->state.in_directive = 1;
226 pfile->state.save_comments = 0;
228 /* Some handlers need the position of the # for diagnostics. */
229 pfile->directive_pos = pfile->lexer_pos;
230 pfile->directive_line = pfile->line;
232 /* Don't save directive tokens for external clients. */
233 pfile->la_saved = pfile->la_write;
237 /* Called when leaving a directive, _Pragma or command-line directive. */
239 end_directive (pfile, skip_line)
243 /* We don't skip for an assembler #. */
246 skip_rest_of_line (pfile);
247 /* "Accept" the newline now. */
252 pfile->la_write = pfile->la_saved;
253 pfile->state.save_comments = ! CPP_OPTION (pfile, discard_comments);
254 pfile->state.in_directive = 0;
255 pfile->state.angled_headers = 0;
256 pfile->state.line_extension = 0;
257 pfile->directive = 0;
260 /* Check if a token's name matches that of a known directive. Put in
261 this file to save exporting dtable and other unneeded information. */
263 _cpp_handle_directive (pfile, indented)
267 const directive *dir = 0;
271 start_directive (pfile);
273 /* Lex the directive name directly. */
274 _cpp_lex_token (pfile, &dname);
276 if (dname.type == CPP_NAME)
278 unsigned int index = dname.val.node->directive_index;
280 dir = &dtable[index - 1];
282 else if (dname.type == CPP_NUMBER)
284 /* # followed by a number is equivalent to #line. Do not
285 recognize this form in assembly language source files or
286 skipped conditional groups. Complain about this form if
287 we're being pedantic, but not if this is regurgitated input
288 (preprocessed or fed back in by the C++ frontend). */
289 if (! pfile->state.skipping && CPP_OPTION (pfile, lang) != CLK_ASM)
291 dir = &dtable[T_LINE];
292 pfile->state.line_extension = 1;
293 _cpp_push_token (pfile, &dname, &pfile->directive_pos);
294 if (CPP_PEDANTIC (pfile) && ! CPP_OPTION (pfile, preprocessed))
295 cpp_pedwarn (pfile, "# followed by integer");
299 pfile->directive = dir;
302 /* Make sure we lex headers correctly, whether skipping or not. */
303 pfile->state.angled_headers = dir->flags & INCL;
305 /* If we are rescanning preprocessed input, only directives tagged
306 with IN_I are honored, and the warnings below are suppressed. */
307 if (CPP_OPTION (pfile, preprocessed))
309 /* Kluge alert. In order to be sure that code like this
312 does not cause '#define foo bar' to get executed when
313 compiled with -save-temps, we recognize directives in
314 -fpreprocessed mode only if the # is in column 1 and the
315 directive name starts in column 2. This output can only
316 be generated by the directive callbacks in cppmain.c (see
317 also the special case in scan_buffer). */
318 if (dir->flags & IN_I && !indented && !(dname.flags & PREV_WHITE))
319 (*dir->handler) (pfile);
320 /* That check misses '# 123' linemarkers. Let them through too. */
321 else if (dname.type == CPP_NUMBER)
322 (*dir->handler) (pfile);
325 /* We don't want to process this directive. Put back the
326 tokens so caller will see them (and issue an error,
328 _cpp_push_token (pfile, &dname, &pfile->directive_pos);
334 /* Traditionally, a directive is ignored unless its # is in
335 column 1. Therefore in code intended to work with K+R
336 compilers, directives added by C89 must have their #
337 indented, and directives present in traditional C must
338 not. This is true even of directives in skipped
339 conditional blocks. */
340 if (CPP_WTRADITIONAL (pfile))
342 if (dir == &dtable[T_ELIF])
344 "suggest not using #elif in traditional C");
345 else if (indented && dir->origin == KANDR)
347 "traditional C ignores #%s with the # indented",
349 else if (!indented && dir->origin != KANDR)
351 "suggest hiding #%s from traditional C with an indented #",
355 /* If we are skipping a failed conditional group, all
356 non-conditional directives are ignored. */
357 if (! pfile->state.skipping || (dir->flags & COND))
359 /* Issue -pedantic warnings for extensions. */
360 if (CPP_PEDANTIC (pfile) && dir->origin == EXTENSION)
361 cpp_pedwarn (pfile, "#%s is a GCC extension", dir->name);
363 /* If we have a directive that is not an opening
364 conditional, invalidate any control macro. */
365 if (! (dir->flags & IF_COND))
366 pfile->mi_valid = false;
368 (*dir->handler) (pfile);
372 else if (dname.type != CPP_EOF && ! pfile->state.skipping)
374 /* An unknown directive. Don't complain about it in assembly
375 source: we don't know where the comments are, and # may
376 introduce assembler pseudo-ops. Don't complain about invalid
377 directives in skipped conditional groups (6.10 p4). */
378 if (CPP_OPTION (pfile, lang) == CLK_ASM)
380 /* Output the # and lookahead token for the assembler. */
381 _cpp_push_token (pfile, &dname, &pfile->directive_pos);
385 cpp_error (pfile, "invalid preprocessing directive #%s",
386 cpp_token_as_text (pfile, &dname));
389 if (pfile->state.in_directive)
390 end_directive (pfile, skip);
394 /* Directive handler wrapper used by the command line option
397 run_directive (pfile, dir_no, type, buf, count)
400 enum cpp_buffer_type type;
406 buffer = cpp_push_buffer (pfile, (const U_CHAR *) buf, count, type, 0, 1);
407 start_directive (pfile);
408 pfile->state.prevent_expansion++;
409 pfile->directive = &dtable[dir_no];
410 (void) (*pfile->directive->handler) (pfile);
411 pfile->state.prevent_expansion--;
413 end_directive (pfile, 1);
414 _cpp_pop_buffer (pfile);
417 /* Checks for validity the macro name in #define, #undef, #ifdef and
418 #ifndef directives. */
419 static cpp_hashnode *
420 lex_macro_node (pfile)
426 /* Lex the macro name directly. */
427 _cpp_lex_token (pfile, &token);
429 /* The token immediately after #define must be an identifier. That
430 identifier may not be "defined", per C99 6.10.8p4.
431 In C++, it may not be any of the "named operators" either,
432 per C++98 [lex.digraph], [lex.key].
433 Finally, the identifier may not have been poisoned. (In that case
434 the lexer has issued the error message for us.) */
436 if (token.type != CPP_NAME)
438 if (token.type == CPP_EOF)
439 cpp_error (pfile, "no macro name given in #%s directive",
440 pfile->directive->name);
441 else if (token.flags & NAMED_OP)
443 "\"%s\" cannot be used as a macro name as it is an operator in C++",
444 NODE_NAME (token.val.node));
446 cpp_error (pfile, "macro names must be identifiers");
451 node = token.val.node;
452 if (node->flags & NODE_POISONED)
455 if (node == pfile->spec_nodes.n_defined)
457 cpp_error (pfile, "\"%s\" cannot be used as a macro name",
465 /* Process a #define directive. Most work is done in cppmacro.c. */
470 cpp_hashnode *node = lex_macro_node (pfile);
474 if (_cpp_create_definition (pfile, node))
475 if (pfile->cb.define)
476 (*pfile->cb.define) (pfile, pfile->directive_line, node);
480 /* Handle #undef. Marks the identifier NT_VOID in the hash table. */
485 cpp_hashnode *node = lex_macro_node (pfile);
487 /* 6.10.3.5 paragraph 2: [#undef] is ignored if the specified identifier
488 is not currently defined as a macro name. */
489 if (node && node->type == NT_MACRO)
492 (*pfile->cb.undef) (pfile, pfile->directive_line, node);
494 if (node->flags & NODE_WARN)
495 cpp_warning (pfile, "undefining \"%s\"", NODE_NAME (node));
497 _cpp_free_definition (node);
502 /* Helper routine used by parse_include. Reinterpret the current line
503 as an h-char-sequence (< ... >); we are looking at the first token
504 after the <. Returns zero on success. */
506 glue_header_name (pfile, header)
511 unsigned char *buffer, *token_mem;
512 size_t len, total_len = 0, capacity = 1024;
514 /* To avoid lexed tokens overwriting our glued name, we can only
515 allocate from the string pool once we've lexed everything. */
517 buffer = (unsigned char *) xmalloc (capacity);
520 cpp_get_token (pfile, &token);
522 if (token.type == CPP_GREATER || token.type == CPP_EOF)
525 len = cpp_token_len (&token);
526 if (total_len + len > capacity)
528 capacity = (capacity + len) * 2;
529 buffer = (unsigned char *) xrealloc (buffer, capacity);
532 if (token.flags & PREV_WHITE)
533 buffer[total_len++] = ' ';
535 total_len = cpp_spell_token (pfile, &token, &buffer[total_len]) - buffer;
538 if (token.type == CPP_EOF)
539 cpp_error (pfile, "missing terminating > character");
542 token_mem = _cpp_pool_alloc (&pfile->ident_pool, total_len + 1);
543 memcpy (token_mem, buffer, total_len);
544 token_mem[total_len] = '\0';
546 header->type = CPP_HEADER_NAME;
547 header->flags &= ~PREV_WHITE;
548 header->val.str.len = total_len;
549 header->val.str.text = token_mem;
553 return token.type == CPP_EOF;
556 /* Parse the header name of #include, #include_next, #import and
557 #pragma dependency. Returns zero on success. */
559 parse_include (pfile, header)
563 const unsigned char *dir;
565 if (pfile->directive == &dtable[T_PRAGMA])
566 dir = U"pragma dependency";
568 dir = pfile->directive->name;
570 /* Allow macro expansion. */
571 cpp_get_token (pfile, header);
572 if (header->type != CPP_STRING && header->type != CPP_HEADER_NAME)
574 if (header->type != CPP_LESS)
576 cpp_error (pfile, "#%s expects \"FILENAME\" or <FILENAME>", dir);
579 if (glue_header_name (pfile, header))
583 if (header->val.str.len == 0)
585 cpp_error (pfile, "empty file name in #%s", dir);
592 /* Handle #include, #include_next and #import. */
594 do_include_common (pfile, type)
596 enum include_type type;
600 /* For #include_next, if this is the primary source file, warn and
601 use the normal search logic. */
602 if (type == IT_INCLUDE_NEXT && ! pfile->buffer->prev)
604 cpp_warning (pfile, "#include_next in primary source file");
607 else if (type == IT_IMPORT && CPP_OPTION (pfile, warn_import))
609 CPP_OPTION (pfile, warn_import) = 0;
611 "#import is obsolete, use an #ifndef wrapper in the header file");
614 if (!parse_include (pfile, &header))
616 /* Prevent #include recursion. */
617 if (pfile->buffer_stack_depth >= CPP_STACK_MAX)
618 cpp_fatal (pfile, "#include nested too deeply");
622 /* Get out of macro context, if we are. */
623 end_directive (pfile, 1);
624 if (pfile->cb.include)
625 (*pfile->cb.include) (pfile, pfile->directive_line,
626 pfile->directive->name, &header);
628 _cpp_execute_include (pfile, &header, type);
637 do_include_common (pfile, IT_INCLUDE);
644 do_include_common (pfile, IT_IMPORT);
648 do_include_next (pfile)
651 do_include_common (pfile, IT_INCLUDE_NEXT);
654 /* Subroutine of do_line. Read possible flags after file name. LAST
655 is the last flag seen; 0 if this is the first flag. Return the flag
656 if it is valid, 0 at the end of the directive. Otherwise complain. */
659 read_flag (pfile, last)
665 _cpp_lex_token (pfile, &token);
666 if (token.type == CPP_NUMBER && token.val.str.len == 1)
668 unsigned int flag = token.val.str.text[0] - '0';
670 if (flag > last && flag <= 4
671 && (flag != 4 || last == 3)
672 && (flag != 2 || last == 0))
676 if (token.type != CPP_EOF)
677 cpp_error (pfile, "invalid flag \"%s\" in line directive",
678 cpp_token_as_text (pfile, &token));
682 /* Another subroutine of do_line. Convert a number in STR, of length
683 LEN, to binary; store it in NUMP, and return 0 if the number was
684 well-formed, 1 if not. Temporary, hopefully. */
686 strtoul_for_line (str, len, nump)
691 unsigned long reg = 0;
705 /* Interpret #line command.
706 Note that the filename string (if any) is treated as if it were an
707 include filename. That means no escape handling. */
713 cpp_buffer *buffer = pfile->buffer;
714 enum lc_reason reason = LC_RENAME;
715 unsigned long new_lineno;
716 unsigned int cap, sysp = pfile->map->sysp;
719 /* C99 raised the minimum limit on #line numbers. */
720 cap = CPP_OPTION (pfile, c99) ? 2147483647 : 32767;
722 /* #line commands expand macros. */
723 cpp_get_token (pfile, &token);
724 if (token.type != CPP_NUMBER
725 || strtoul_for_line (token.val.str.text, token.val.str.len, &new_lineno))
727 cpp_error (pfile, "\"%s\" after #line is not a positive integer",
728 cpp_token_as_text (pfile, &token));
732 if (CPP_PEDANTIC (pfile) && ! pfile->state.line_extension
733 && (new_lineno == 0 || new_lineno > cap))
734 cpp_pedwarn (pfile, "line number out of range");
736 cpp_get_token (pfile, &token);
737 if (token.type == CPP_STRING)
739 buffer->nominal_fname = (const char *) token.val.str.text;
741 /* Only accept flags for the # 55 form. */
742 if (pfile->state.line_extension)
747 flag = read_flag (pfile, 0);
751 /* Fake an include for cpp_included (). */
752 _cpp_fake_include (pfile, buffer->nominal_fname);
753 flag = read_flag (pfile, flag);
758 flag = read_flag (pfile, flag);
763 flag = read_flag (pfile, flag);
770 else if (token.type != CPP_EOF)
772 cpp_error (pfile, "\"%s\" is not a valid filename",
773 cpp_token_as_text (pfile, &token));
777 end_directive (pfile, 1);
778 _cpp_do_file_change (pfile, reason, (const char *) buffer->nominal_fname,
782 /* Arrange the file_change callback. pfile->line has changed to
783 FILE_LINE of TO_FILE, for reason REASON. SYSP is 1 for a system
784 header, 2 for a sytem header that needs to be extern "C" protected,
785 and zero otherwise. */
787 _cpp_do_file_change (pfile, reason, to_file, file_line, sysp)
789 enum lc_reason reason;
791 unsigned int file_line;
794 pfile->map = add_line_map (&pfile->line_maps, reason, sysp,
795 pfile->line, to_file, file_line);
797 if (pfile->cb.file_change)
798 (*pfile->cb.file_change) (pfile, pfile->map);
802 * Report a warning or error detected by the program we are
803 * processing. Use the directive's tokens in the error message.
807 do_diagnostic (pfile, code, print_dir)
809 enum error_type code;
812 if (_cpp_begin_message (pfile, code, NULL, 0))
815 fprintf (stderr, "#%s ", pfile->directive->name);
816 pfile->state.prevent_expansion++;
817 cpp_output_line (pfile, stderr);
818 pfile->state.prevent_expansion--;
826 do_diagnostic (pfile, ERROR, 1);
833 /* We want #warning diagnostics to be emitted in system headers too. */
834 do_diagnostic (pfile, WARNING_SYSHDR, 1);
837 /* Report program identification. */
845 cpp_get_token (pfile, &str);
846 if (str.type != CPP_STRING)
847 cpp_error (pfile, "invalid #ident");
848 else if (pfile->cb.ident)
849 (*pfile->cb.ident) (pfile, pfile->directive_line, &str.val.str);
854 /* Pragmata handling. We handle some of these, and pass the rest on
855 to the front end. C99 defines three pragmas and says that no macro
856 expansion is to be performed on them; whether or not macro
857 expansion happens for other pragmas is implementation defined.
858 This implementation never macro-expands the text after #pragma. */
860 /* Sub-handlers for the pragmas needing treatment here.
861 They return 1 if the token buffer is to be popped, 0 if not. */
862 typedef void (*pragma_cb) PARAMS ((cpp_reader *));
865 struct pragma_entry *next;
871 struct pragma_entry *space;
876 cpp_register_pragma (pfile, space, name, handler)
882 struct pragma_entry **x, *new;
888 struct pragma_entry *p = pfile->pragmas;
889 len = strlen (space);
892 if (p->isnspace && p->len == len && !memcmp (p->name, space, len))
899 cpp_ice (pfile, "unknown #pragma namespace %s", space);
904 new = xnew (struct pragma_entry);
906 new->len = strlen (name);
908 new->u.handler = handler;
915 cpp_register_pragma_space (pfile, space)
919 struct pragma_entry *new;
920 const struct pragma_entry *p = pfile->pragmas;
921 size_t len = strlen (space);
925 if (p->isnspace && p->len == len && !memcmp (p->name, space, len))
926 /* Multiple different callers are allowed to register the same
932 new = xnew (struct pragma_entry);
938 new->next = pfile->pragmas;
939 pfile->pragmas = new;
943 _cpp_init_internal_pragmas (pfile)
947 cpp_register_pragma (pfile, 0, "poison", do_pragma_poison);
948 cpp_register_pragma (pfile, 0, "once", do_pragma_once);
951 cpp_register_pragma_space (pfile, "GCC");
953 cpp_register_pragma (pfile, "GCC", "poison", do_pragma_poison);
954 cpp_register_pragma (pfile, "GCC", "system_header", do_pragma_system_header);
955 cpp_register_pragma (pfile, "GCC", "dependency", do_pragma_dependency);
962 pragma_cb handler = NULL;
963 const struct pragma_entry *p;
967 pfile->state.prevent_expansion++;
968 cpp_start_lookahead (pfile);
971 cpp_get_token (pfile, &tok);
972 if (tok.type == CPP_NAME)
974 const cpp_hashnode *node = tok.val.node;
975 size_t len = NODE_LEN (node);
979 if (strlen (p->name) == len
980 && !memcmp (p->name, NODE_NAME (node), len))
989 handler = p->u.handler;
997 cpp_stop_lookahead (pfile, handler != NULL);
998 pfile->state.prevent_expansion--;
1002 else if (pfile->cb.def_pragma)
1003 (*pfile->cb.def_pragma) (pfile, pfile->directive_line);
1007 do_pragma_once (pfile)
1010 cpp_warning (pfile, "#pragma once is obsolete");
1012 if (pfile->buffer->prev == NULL)
1013 cpp_warning (pfile, "#pragma once in main file");
1015 _cpp_never_reread (pfile->buffer->inc);
1021 do_pragma_poison (pfile)
1024 /* Poison these symbols so that all subsequent usage produces an
1029 pfile->state.poisoned_ok = 1;
1032 _cpp_lex_token (pfile, &tok);
1033 if (tok.type == CPP_EOF)
1035 if (tok.type != CPP_NAME)
1037 cpp_error (pfile, "invalid #pragma GCC poison directive");
1042 if (hp->flags & NODE_POISONED)
1045 if (hp->type == NT_MACRO)
1046 cpp_warning (pfile, "poisoning existing macro \"%s\"", NODE_NAME (hp));
1047 _cpp_free_definition (hp);
1048 hp->flags |= NODE_POISONED | NODE_DIAGNOSTIC;
1050 pfile->state.poisoned_ok = 0;
1053 /* Mark the current header as a system header. This will suppress
1054 some categories of warnings (notably those from -pedantic). It is
1055 intended for use in system libraries that cannot be implemented in
1056 conforming C, but cannot be certain that their headers appear in a
1057 system include directory. To prevent abuse, it is rejected in the
1058 primary source file. */
1060 do_pragma_system_header (pfile)
1063 cpp_buffer *buffer = pfile->buffer;
1065 if (buffer->prev == 0)
1066 cpp_warning (pfile, "#pragma system_header ignored outside include file");
1070 end_directive (pfile, 1);
1071 cpp_make_system_header (pfile, 1, 0);
1075 /* Check the modified date of the current include file against a specified
1076 file. Issue a diagnostic, if the specified file is newer. We use this to
1077 determine if a fixed header should be refixed. */
1079 do_pragma_dependency (pfile)
1082 cpp_token header, msg;
1085 if (parse_include (pfile, &header))
1088 ordering = _cpp_compare_file_date (pfile, &header);
1090 cpp_warning (pfile, "cannot find source %s",
1091 cpp_token_as_text (pfile, &header));
1092 else if (ordering > 0)
1094 cpp_warning (pfile, "current file is older than %s",
1095 cpp_token_as_text (pfile, &header));
1096 cpp_start_lookahead (pfile);
1097 cpp_get_token (pfile, &msg);
1098 cpp_stop_lookahead (pfile, msg.type == CPP_EOF);
1099 if (msg.type != CPP_EOF)
1100 do_diagnostic (pfile, WARNING, 0);
1104 /* Check syntax is "(string-literal)". Returns 0 on success. */
1106 get__Pragma_string (pfile, string)
1112 cpp_get_token (pfile, &paren);
1113 if (paren.type != CPP_OPEN_PAREN)
1116 cpp_get_token (pfile, string);
1117 if (string->type != CPP_STRING && string->type != CPP_WSTRING)
1120 cpp_get_token (pfile, &paren);
1121 return paren.type != CPP_CLOSE_PAREN;
1124 /* Returns a malloced buffer containing a destringized cpp_string by
1125 removing the first \ of \" and \\ sequences. */
1126 static unsigned char *
1127 destringize (in, len)
1128 const cpp_string *in;
1131 const unsigned char *src, *limit;
1132 unsigned char *dest, *result;
1134 dest = result = (unsigned char *) xmalloc (in->len);
1135 for (src = in->text, limit = src + in->len; src < limit;)
1137 /* We know there is a character following the backslash. */
1138 if (*src == '\\' && (src[1] == '\\' || src[1] == '"'))
1143 *len = dest - result;
1148 _cpp_do__Pragma (pfile)
1152 unsigned char *buffer;
1154 cpp_lexer_pos orig_pos;
1156 orig_pos = pfile->lexer_pos;
1157 if (get__Pragma_string (pfile, &string))
1158 cpp_error (pfile, "_Pragma takes a parenthesized string literal");
1161 buffer = destringize (&string.val.str, &len);
1162 run_directive (pfile, T_PRAGMA, BUF_PRAGMA, (char *) buffer, len);
1163 free ((PTR) buffer);
1164 pfile->lexer_pos = orig_pos;
1165 pfile->line = pfile->lexer_pos.line;
1169 /* Just ignore #sccs, on systems where we define it at all. */
1170 #ifdef SCCS_DIRECTIVE
1173 cpp_reader *pfile ATTRIBUTE_UNUSED;
1184 if (! pfile->state.skipping)
1186 const cpp_hashnode *node = lex_macro_node (pfile);
1189 skip = node->type != NT_MACRO;
1195 push_conditional (pfile, skip, T_IFDEF, 0);
1203 const cpp_hashnode *node = 0;
1205 if (! pfile->state.skipping)
1207 node = lex_macro_node (pfile);
1209 skip = node->type == NT_MACRO;
1215 push_conditional (pfile, skip, T_IFNDEF, node);
1218 /* _cpp_parse_expr puts a macro in a "#if !defined ()" expression in
1219 pfile->mi_ind_cmacro so we can handle multiple-include
1220 optimisations. If macro expansion occurs in the expression, we
1221 cannot treat it as a controlling conditional, since the expansion
1222 could change in the future. That is handled by cpp_get_token. */
1230 if (! pfile->state.skipping)
1231 skip = _cpp_parse_expr (pfile) == 0;
1233 push_conditional (pfile, skip, T_IF, pfile->mi_ind_cmacro);
1236 /* Flip skipping state if appropriate and continue without changing
1237 if_stack; this is so that the error message for missing #endif's
1238 etc. will point to the original #if. */
1244 cpp_buffer *buffer = pfile->buffer;
1245 struct if_stack *ifs = buffer->if_stack;
1248 cpp_error (pfile, "#else without #if");
1251 if (ifs->type == T_ELSE)
1253 cpp_error (pfile, "#else after #else");
1254 cpp_error_with_line (pfile, ifs->pos.line, ifs->pos.col,
1255 "the conditional began here");
1259 /* Skip any future (erroneous) #elses or #elifs. */
1260 pfile->state.skipping = ifs->skip_elses;
1261 ifs->skip_elses = true;
1263 /* Invalidate any controlling macro. */
1266 /* Only check EOL if was not originally skipping. */
1267 if (!ifs->was_skipping)
1272 /* handle a #elif directive by not changing if_stack either. see the
1273 comment above do_else. */
1279 cpp_buffer *buffer = pfile->buffer;
1280 struct if_stack *ifs = buffer->if_stack;
1283 cpp_error (pfile, "#elif without #if");
1286 if (ifs->type == T_ELSE)
1288 cpp_error (pfile, "#elif after #else");
1289 cpp_error_with_line (pfile, ifs->pos.line, ifs->pos.col,
1290 "the conditional began here");
1294 /* Only evaluate this if we aren't skipping elses. During
1295 evaluation, set skipping to false to get lexer warnings. */
1296 if (ifs->skip_elses)
1297 pfile->state.skipping = 1;
1300 pfile->state.skipping = 0;
1301 pfile->state.skipping = ! _cpp_parse_expr (pfile);
1302 ifs->skip_elses = ! pfile->state.skipping;
1305 /* Invalidate any controlling macro. */
1310 /* #endif pops the if stack and resets pfile->state.skipping. */
1316 cpp_buffer *buffer = pfile->buffer;
1317 struct if_stack *ifs = buffer->if_stack;
1320 cpp_error (pfile, "#endif without #if");
1323 /* Only check EOL if was not originally skipping. */
1324 if (!ifs->was_skipping)
1327 /* If potential control macro, we go back outside again. */
1328 if (ifs->next == 0 && ifs->mi_cmacro)
1330 pfile->mi_valid = true;
1331 pfile->mi_cmacro = ifs->mi_cmacro;
1334 buffer->if_stack = ifs->next;
1335 pfile->state.skipping = ifs->was_skipping;
1336 obstack_free (&pfile->buffer_ob, ifs);
1340 /* Push an if_stack entry and set pfile->state.skipping accordingly.
1341 If this is a #if or #ifndef, CMACRO is a potentially controlling
1342 macro - we need to check here that we are at the top of the file. */
1345 push_conditional (pfile, skip, type, cmacro)
1349 const cpp_hashnode *cmacro;
1351 struct if_stack *ifs;
1352 cpp_buffer *buffer = pfile->buffer;
1354 ifs = xobnew (&pfile->buffer_ob, struct if_stack);
1355 ifs->pos = pfile->directive_pos;
1356 ifs->next = buffer->if_stack;
1357 ifs->skip_elses = pfile->state.skipping || !skip;
1358 ifs->was_skipping = pfile->state.skipping;
1360 /* This condition is effectively a test for top-of-file. */
1361 if (pfile->mi_valid && pfile->mi_cmacro == 0)
1362 ifs->mi_cmacro = cmacro;
1366 pfile->state.skipping = skip;
1367 buffer->if_stack = ifs;
1370 /* Read the tokens of the answer into the macro pool. Only commit the
1371 memory if we intend it as permanent storage, i.e. the #assert case.
1372 Returns 0 on success. */
1375 parse_answer (pfile, answerp, type)
1377 struct answer **answerp;
1380 cpp_token paren, *token;
1381 struct answer *answer;
1383 if (POOL_FRONT (&pfile->macro_pool) + sizeof (struct answer) >
1384 POOL_LIMIT (&pfile->macro_pool))
1385 _cpp_next_chunk (&pfile->macro_pool, sizeof (struct answer), 0);
1386 answer = (struct answer *) POOL_FRONT (&pfile->macro_pool);
1389 /* In a conditional, it is legal to not have an open paren. We
1390 should save the following token in this case. */
1392 cpp_start_lookahead (pfile);
1393 cpp_get_token (pfile, &paren);
1395 cpp_stop_lookahead (pfile, paren.type == CPP_OPEN_PAREN);
1397 /* If not a paren, see if we're OK. */
1398 if (paren.type != CPP_OPEN_PAREN)
1400 /* In a conditional no answer is a test for any answer. It
1401 could be followed by any token. */
1405 /* #unassert with no answer is valid - it removes all answers. */
1406 if (type == T_UNASSERT && paren.type == CPP_EOF)
1409 cpp_error (pfile, "missing '(' after predicate");
1415 token = &answer->first[answer->count];
1416 /* Check we have room for the token. */
1417 if ((unsigned char *) (token + 1) >= POOL_LIMIT (&pfile->macro_pool))
1419 _cpp_next_chunk (&pfile->macro_pool, sizeof (cpp_token),
1420 (unsigned char **) &answer);
1421 token = &answer->first[answer->count];
1424 cpp_get_token (pfile, token);
1425 if (token->type == CPP_CLOSE_PAREN)
1428 if (token->type == CPP_EOF)
1430 cpp_error (pfile, "missing ')' to complete answer");
1436 if (answer->count == 0)
1438 cpp_error (pfile, "predicate's answer is empty");
1442 /* Drop whitespace at start. */
1443 answer->first->flags &= ~PREV_WHITE;
1446 if (type == T_ASSERT || type == T_UNASSERT)
1451 /* Parses an assertion, returning a pointer to the hash node of the
1452 predicate, or 0 on error. If an answer was supplied, it is placed
1453 in ANSWERP, otherwise it is set to 0. */
1454 static cpp_hashnode *
1455 parse_assertion (pfile, answerp, type)
1457 struct answer **answerp;
1460 cpp_hashnode *result = 0;
1461 cpp_token predicate;
1463 /* We don't expand predicates or answers. */
1464 pfile->state.prevent_expansion++;
1467 cpp_get_token (pfile, &predicate);
1468 if (predicate.type == CPP_EOF)
1469 cpp_error (pfile, "assertion without predicate");
1470 else if (predicate.type != CPP_NAME)
1471 cpp_error (pfile, "predicate must be an identifier");
1472 else if (parse_answer (pfile, answerp, type) == 0)
1474 unsigned int len = NODE_LEN (predicate.val.node);
1475 unsigned char *sym = alloca (len + 1);
1477 /* Prefix '#' to get it out of macro namespace. */
1479 memcpy (sym + 1, NODE_NAME (predicate.val.node), len);
1480 result = cpp_lookup (pfile, sym, len + 1);
1483 pfile->state.prevent_expansion--;
1487 /* Returns a pointer to the pointer to the answer in the answer chain,
1488 or a pointer to NULL if the answer is not in the chain. */
1489 static struct answer **
1490 find_answer (node, candidate)
1492 const struct answer *candidate;
1495 struct answer **result;
1497 for (result = &node->value.answers; *result; result = &(*result)->next)
1499 struct answer *answer = *result;
1501 if (answer->count == candidate->count)
1503 for (i = 0; i < answer->count; i++)
1504 if (! _cpp_equiv_tokens (&answer->first[i], &candidate->first[i]))
1507 if (i == answer->count)
1515 /* Test an assertion within a preprocessor conditional. Returns
1516 non-zero on failure, zero on success. On success, the result of
1517 the test is written into VALUE. */
1519 _cpp_test_assertion (pfile, value)
1523 struct answer *answer;
1526 node = parse_assertion (pfile, &answer, T_IF);
1528 *value = (node->type == NT_ASSERTION &&
1529 (answer == 0 || *find_answer (node, answer) != 0));
1531 /* We don't commit the memory for the answer - it's temporary only. */
1539 struct answer *new_answer;
1542 node = parse_assertion (pfile, &new_answer, T_ASSERT);
1545 /* Place the new answer in the answer list. First check there
1546 is not a duplicate. */
1547 new_answer->next = 0;
1548 if (node->type == NT_ASSERTION)
1550 if (*find_answer (node, new_answer))
1552 cpp_warning (pfile, "\"%s\" re-asserted", NODE_NAME (node) + 1);
1555 new_answer->next = node->value.answers;
1557 node->type = NT_ASSERTION;
1558 node->value.answers = new_answer;
1559 POOL_COMMIT (&pfile->macro_pool, (sizeof (struct answer)
1560 + (new_answer->count - 1)
1561 * sizeof (cpp_token)));
1570 struct answer *answer;
1572 node = parse_assertion (pfile, &answer, T_UNASSERT);
1573 /* It isn't an error to #unassert something that isn't asserted. */
1574 if (node && node->type == NT_ASSERTION)
1578 struct answer **p = find_answer (node, answer), *temp;
1580 /* Remove the answer from the list. */
1585 /* Did we free the last answer? */
1586 if (node->value.answers == 0)
1587 node->type = NT_VOID;
1590 _cpp_free_definition (node);
1593 /* We don't commit the memory for the answer - it's temporary only. */
1596 /* These are for -D, -U, -A. */
1598 /* Process the string STR as if it appeared as the body of a #define.
1599 If STR is just an identifier, define it with value 1.
1600 If STR has anything after the identifier, then it should
1601 be identifier=definition. */
1604 cpp_define (pfile, str)
1611 /* Copy the entire option so we can modify it.
1612 Change the first "=" in the string to a space. If there is none,
1613 tack " 1" on the end. */
1615 /* Length including the null. */
1616 count = strlen (str);
1617 buf = (char *) alloca (count + 2);
1618 memcpy (buf, str, count);
1620 p = strchr (str, '=');
1629 run_directive (pfile, T_DEFINE, BUF_CL_OPTION, buf, count);
1632 /* Slight variant of the above for use by initialize_builtins. */
1634 _cpp_define_builtin (pfile, str)
1638 run_directive (pfile, T_DEFINE, BUF_BUILTIN, str, strlen (str));
1641 /* Process MACRO as if it appeared as the body of an #undef. */
1643 cpp_undef (pfile, macro)
1647 run_directive (pfile, T_UNDEF, BUF_CL_OPTION, macro, strlen (macro));
1650 /* Process the string STR as if it appeared as the body of a #assert. */
1652 cpp_assert (pfile, str)
1656 handle_assertion (pfile, str, T_ASSERT);
1659 /* Process STR as if it appeared as the body of an #unassert. */
1661 cpp_unassert (pfile, str)
1665 handle_assertion (pfile, str, T_UNASSERT);
1668 /* Common code for cpp_assert (-A) and cpp_unassert (-A-). */
1670 handle_assertion (pfile, str, type)
1675 size_t count = strlen (str);
1676 const char *p = strchr (str, '=');
1680 /* Copy the entire option so we can modify it. Change the first
1681 "=" in the string to a '(', and tack a ')' on the end. */
1682 char *buf = (char *) alloca (count + 1);
1684 memcpy (buf, str, count);
1690 run_directive (pfile, type, BUF_CL_OPTION, str, count);
1693 /* The number of errors for a given reader. */
1698 return pfile->errors;
1701 /* The options structure. */
1703 cpp_get_options (pfile)
1706 return &pfile->opts;
1709 /* The callbacks structure. */
1711 cpp_get_callbacks (pfile)
1717 /* The line map set. */
1718 const struct line_maps *
1719 cpp_get_line_maps (pfile)
1722 return &pfile->line_maps;
1725 /* Copy the given callbacks structure to our own. */
1727 cpp_set_callbacks (pfile, cb)
1734 /* Push a new buffer on the buffer stack. Returns the new buffer; it
1735 doesn't fail. It does not generate a file change call back; that
1736 is the responsibility of the caller. */
1738 cpp_push_buffer (pfile, buffer, len, type, filename, return_at_eof)
1740 const U_CHAR *buffer;
1742 enum cpp_buffer_type type;
1743 const char *filename;
1746 cpp_buffer *new = xobnew (&pfile->buffer_ob, cpp_buffer);
1748 if (type == BUF_BUILTIN)
1749 filename = _("<builtin>");
1750 else if (type == BUF_CL_OPTION)
1751 filename = _("<command line>");
1752 else if (type == BUF_PRAGMA)
1753 filename = "<_Pragma>";
1755 /* Clears, amongst other things, if_stack and mi_cmacro. */
1756 memset (new, 0, sizeof (cpp_buffer));
1758 new->line_base = new->buf = new->cur = buffer;
1759 new->rlimit = buffer + len;
1761 /* No read ahead or extra char initially. */
1762 new->read_ahead = EOF;
1763 new->extra_char = EOF;
1765 /* Preprocessed files, builtins, _Pragma and command line
1766 options don't do trigraph and escaped newline processing. */
1767 new->from_stage3 = type != BUF_FILE || CPP_OPTION (pfile, preprocessed);
1769 if (*filename == '\0')
1770 new->nominal_fname = _("<stdin>");
1772 new->nominal_fname = filename;
1774 new->prev = pfile->buffer;
1776 new->return_at_eof = return_at_eof;
1778 pfile->buffer_stack_depth++;
1779 pfile->buffer = new;
1784 /* If called from do_line, pops a single buffer. Otherwise pops all
1785 buffers until a real file is reached. Generates appropriate
1788 _cpp_pop_buffer (pfile)
1791 cpp_buffer *buffer = pfile->buffer;
1792 struct if_stack *ifs;
1794 /* Walk back up the conditional stack till we reach its level at
1795 entry to this file, issuing error messages. */
1796 for (ifs = buffer->if_stack; ifs; ifs = ifs->next)
1797 cpp_error_with_line (pfile, ifs->pos.line, ifs->pos.col,
1798 "unterminated #%s", dtable[ifs->type].name);
1800 /* Update the reader's buffer before _cpp_do_file_change. */
1801 pfile->buffer = buffer->prev;
1802 pfile->buffer_stack_depth--;
1804 if (buffer->type == BUF_FILE)
1806 /* Callbacks are not generated for popping the main file. */
1808 _cpp_do_file_change (pfile, LC_LEAVE, 0, 0, 0);
1810 _cpp_pop_file_buffer (pfile, buffer);
1813 obstack_free (&pfile->buffer_ob, buffer);
1815 /* The output line can fall out of sync if we missed the final
1816 newline from the previous buffer, for example because of an
1817 unterminated comment. Similarly, skipping needs to be cleared in
1818 case of a missing #endif. */
1819 pfile->lexer_pos.output_line = pfile->line;
1820 pfile->state.skipping = 0;
1824 _cpp_init_directives (pfile)
1830 /* Register the directives. */
1831 for (i = 0; i < (unsigned int) N_DIRECTIVES; i++)
1833 node = cpp_lookup (pfile, dtable[i].name, dtable[i].length);
1834 node->directive_index = i + 1;