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 /* Skip any remaining tokens in a directive. */
183 skip_rest_of_line (pfile)
188 /* Discard all input lookaheads. */
189 while (pfile->la_read)
190 _cpp_release_lookahead (pfile);
192 /* Discard all stacked contexts. */
193 while (pfile->context != &pfile->base_context)
194 _cpp_pop_context (pfile);
196 /* Sweep up all tokens remaining on the line. */
197 while (!pfile->state.next_bol)
198 _cpp_lex_token (pfile, &token);
201 /* Ensure there are no stray tokens at the end of a directive. */
206 if (!pfile->state.next_bol)
210 _cpp_lex_token (pfile, &token);
211 if (token.type != CPP_EOF)
212 cpp_pedwarn (pfile, "extra tokens at end of #%s directive",
213 pfile->directive->name);
217 /* Called when entering a directive, _Pragma or command-line directive. */
219 start_directive (pfile)
222 /* Setup in-directive state. */
223 pfile->state.in_directive = 1;
224 pfile->state.save_comments = 0;
226 /* Some handlers need the position of the # for diagnostics. */
227 pfile->directive_pos = pfile->lexer_pos;
229 /* Don't save directive tokens for external clients. */
230 pfile->la_saved = pfile->la_write;
234 /* Called when leaving a directive, _Pragma or command-line directive. */
236 end_directive (pfile, skip_line)
240 /* We don't skip for an assembler #. */
242 skip_rest_of_line (pfile);
245 pfile->la_write = pfile->la_saved;
246 pfile->state.save_comments = ! CPP_OPTION (pfile, discard_comments);
247 pfile->state.in_directive = 0;
248 pfile->state.angled_headers = 0;
249 pfile->state.line_extension = 0;
250 pfile->directive = 0;
253 /* Check if a token's name matches that of a known directive. Put in
254 this file to save exporting dtable and other unneeded information. */
256 _cpp_handle_directive (pfile, indented)
260 const directive *dir = 0;
264 start_directive (pfile);
266 /* Lex the directive name directly. */
267 _cpp_lex_token (pfile, &dname);
269 if (dname.type == CPP_NAME)
271 unsigned int index = dname.val.node->directive_index;
273 dir = &dtable[index - 1];
275 else if (dname.type == CPP_NUMBER)
277 /* # followed by a number is equivalent to #line. Do not
278 recognize this form in assembly language source files or
279 skipped conditional groups. Complain about this form if
280 we're being pedantic, but not if this is regurgitated input
281 (preprocessed or fed back in by the C++ frontend). */
282 if (! pfile->state.skipping && CPP_OPTION (pfile, lang) != CLK_ASM)
284 dir = &dtable[T_LINE];
285 pfile->state.line_extension = 1;
286 _cpp_push_token (pfile, &dname, &pfile->directive_pos);
287 if (CPP_PEDANTIC (pfile) && ! CPP_OPTION (pfile, preprocessed))
288 cpp_pedwarn (pfile, "# followed by integer");
292 pfile->directive = dir;
295 /* Make sure we lex headers correctly, whether skipping or not. */
296 pfile->state.angled_headers = dir->flags & INCL;
298 /* If we are rescanning preprocessed input, only directives tagged
299 with IN_I are honored, and the warnings below are suppressed. */
300 if (CPP_OPTION (pfile, preprocessed))
302 /* Kluge alert. In order to be sure that code like this
305 does not cause '#define foo bar' to get executed when
306 compiled with -save-temps, we recognize directives in
307 -fpreprocessed mode only if the # is in column 1 and the
308 directive name starts in column 2. This output can only
309 be generated by the directive callbacks in cppmain.c (see
310 also the special case in scan_buffer). */
311 if (dir->flags & IN_I && !indented && !(dname.flags & PREV_WHITE))
312 (*dir->handler) (pfile);
313 /* That check misses '# 123' linemarkers. Let them through too. */
314 else if (dname.type == CPP_NUMBER)
315 (*dir->handler) (pfile);
318 /* We don't want to process this directive. Put back the
319 tokens so caller will see them (and issue an error,
321 _cpp_push_token (pfile, &dname, &pfile->directive_pos);
327 /* Traditionally, a directive is ignored unless its # is in
328 column 1. Therefore in code intended to work with K+R
329 compilers, directives added by C89 must have their #
330 indented, and directives present in traditional C must
331 not. This is true even of directives in skipped
332 conditional blocks. */
333 if (CPP_WTRADITIONAL (pfile))
335 if (dir == &dtable[T_ELIF])
337 "suggest not using #elif in traditional C");
338 else if (indented && dir->origin == KANDR)
340 "traditional C ignores #%s with the # indented",
342 else if (!indented && dir->origin != KANDR)
344 "suggest hiding #%s from traditional C with an indented #",
348 /* If we are skipping a failed conditional group, all
349 non-conditional directives are ignored. */
350 if (! pfile->state.skipping || (dir->flags & COND))
352 /* Issue -pedantic warnings for extensions. */
353 if (CPP_PEDANTIC (pfile) && dir->origin == EXTENSION)
354 cpp_pedwarn (pfile, "#%s is a GCC extension", dir->name);
356 /* If we have a directive that is not an opening
357 conditional, invalidate any control macro. */
358 if (! (dir->flags & IF_COND))
359 pfile->mi_valid = false;
361 (*dir->handler) (pfile);
365 else if (dname.type != CPP_EOF && ! pfile->state.skipping)
367 /* An unknown directive. Don't complain about it in assembly
368 source: we don't know where the comments are, and # may
369 introduce assembler pseudo-ops. Don't complain about invalid
370 directives in skipped conditional groups (6.10 p4). */
371 if (CPP_OPTION (pfile, lang) == CLK_ASM)
373 /* Output the # and lookahead token for the assembler. */
374 _cpp_push_token (pfile, &dname, &pfile->directive_pos);
378 cpp_error (pfile, "invalid preprocessing directive #%s",
379 cpp_token_as_text (pfile, &dname));
382 if (pfile->state.in_directive)
383 end_directive (pfile, skip);
387 /* Directive handler wrapper used by the command line option
390 run_directive (pfile, dir_no, type, buf, count)
393 enum cpp_buffer_type type;
397 unsigned int output_line = pfile->lexer_pos.output_line;
400 buffer = cpp_push_buffer (pfile, (const U_CHAR *) buf, count, type, 0);
402 if (dir_no == T_PRAGMA)
404 /* A kludge to avoid line markers for _Pragma. */
405 pfile->lexer_pos.output_line = output_line;
406 /* Avoid interpretation of directives in a _Pragma string. */
407 pfile->state.next_bol = 0;
410 start_directive (pfile);
411 pfile->state.prevent_expansion++;
412 pfile->directive = &dtable[dir_no];
413 (void) (*pfile->directive->handler) (pfile);
414 pfile->state.prevent_expansion--;
416 end_directive (pfile, 1);
418 cpp_pop_buffer (pfile);
421 /* Checks for validity the macro name in #define, #undef, #ifdef and
422 #ifndef directives. */
423 static cpp_hashnode *
424 lex_macro_node (pfile)
430 /* Lex the macro name directly. */
431 _cpp_lex_token (pfile, &token);
433 /* The token immediately after #define must be an identifier. That
434 identifier may not be "defined", per C99 6.10.8p4.
435 In C++, it may not be any of the "named operators" either,
436 per C++98 [lex.digraph], [lex.key].
437 Finally, the identifier may not have been poisoned. (In that case
438 the lexer has issued the error message for us.) */
440 if (token.type != CPP_NAME)
442 if (token.type == CPP_EOF)
443 cpp_error (pfile, "no macro name given in #%s directive",
444 pfile->directive->name);
445 else if (token.flags & NAMED_OP)
447 "\"%s\" cannot be used as a macro name as it is an operator in C++",
448 NODE_NAME (token.val.node));
450 cpp_error (pfile, "macro names must be identifiers");
455 node = token.val.node;
456 if (node->flags & NODE_POISONED)
459 if (node == pfile->spec_nodes.n_defined)
461 cpp_error (pfile, "\"%s\" cannot be used as a macro name",
469 /* Process a #define directive. Most work is done in cppmacro.c. */
474 cpp_hashnode *node = lex_macro_node (pfile);
478 if (_cpp_create_definition (pfile, node))
479 if (pfile->cb.define)
480 (*pfile->cb.define) (pfile, node);
484 /* Handle #undef. Marks the identifier NT_VOID in the hash table. */
489 cpp_hashnode *node = lex_macro_node (pfile);
491 /* 6.10.3.5 paragraph 2: [#undef] is ignored if the specified identifier
492 is not currently defined as a macro name. */
493 if (node && node->type == NT_MACRO)
496 (*pfile->cb.undef) (pfile, node);
498 if (node->flags & NODE_WARN)
499 cpp_warning (pfile, "undefining \"%s\"", NODE_NAME (node));
501 _cpp_free_definition (node);
506 /* Helper routine used by parse_include. Reinterpret the current line
507 as an h-char-sequence (< ... >); we are looking at the first token
508 after the <. Returns zero on success. */
510 glue_header_name (pfile, header)
515 unsigned char *buffer, *token_mem;
516 size_t len, total_len = 0, capacity = 1024;
518 /* To avoid lexed tokens overwriting our glued name, we can only
519 allocate from the string pool once we've lexed everything. */
521 buffer = (unsigned char *) xmalloc (capacity);
524 cpp_get_token (pfile, &token);
526 if (token.type == CPP_GREATER || token.type == CPP_EOF)
529 len = cpp_token_len (&token);
530 if (total_len + len > capacity)
532 capacity = (capacity + len) * 2;
533 buffer = (unsigned char *) xrealloc (buffer, capacity);
536 if (token.flags & PREV_WHITE)
537 buffer[total_len++] = ' ';
539 total_len = cpp_spell_token (pfile, &token, &buffer[total_len]) - buffer;
542 if (token.type == CPP_EOF)
543 cpp_error (pfile, "missing terminating > character");
546 token_mem = _cpp_pool_alloc (&pfile->ident_pool, total_len + 1);
547 memcpy (token_mem, buffer, total_len);
548 token_mem[total_len] = '\0';
550 header->type = CPP_HEADER_NAME;
551 header->flags &= ~PREV_WHITE;
552 header->val.str.len = total_len;
553 header->val.str.text = token_mem;
557 return token.type == CPP_EOF;
560 /* Parse the header name of #include, #include_next, #import and
561 #pragma dependency. Returns zero on success. */
563 parse_include (pfile, header)
567 const unsigned char *dir;
569 if (pfile->directive == &dtable[T_PRAGMA])
570 dir = U"pragma dependency";
572 dir = pfile->directive->name;
574 /* Allow macro expansion. */
575 cpp_get_token (pfile, header);
576 if (header->type != CPP_STRING && header->type != CPP_HEADER_NAME)
578 if (header->type != CPP_LESS)
580 cpp_error (pfile, "#%s expects \"FILENAME\" or <FILENAME>", dir);
583 if (glue_header_name (pfile, header))
587 if (header->val.str.len == 0)
589 cpp_error (pfile, "empty file name in #%s", dir);
596 /* Handle #include, #include_next and #import. */
598 do_include_common (pfile, type)
600 enum include_type type;
604 /* For #include_next, if this is the primary source file, warn and
605 use the normal search logic. */
606 if (type == IT_INCLUDE_NEXT && ! pfile->buffer->prev)
608 cpp_warning (pfile, "#include_next in primary source file");
611 else if (type == IT_IMPORT && CPP_OPTION (pfile, warn_import))
613 CPP_OPTION (pfile, warn_import) = 0;
615 "#import is obsolete, use an #ifndef wrapper in the header file");
618 if (!parse_include (pfile, &header))
620 /* Prevent #include recursion. */
621 if (pfile->buffer_stack_depth >= CPP_STACK_MAX)
622 cpp_fatal (pfile, "#include nested too deeply");
626 /* Get out of macro context, if we are. */
627 end_directive (pfile, 1);
628 if (pfile->cb.include)
629 (*pfile->cb.include) (pfile, pfile->directive->name, &header);
631 _cpp_execute_include (pfile, &header, type);
640 do_include_common (pfile, IT_INCLUDE);
647 do_include_common (pfile, IT_IMPORT);
651 do_include_next (pfile)
654 do_include_common (pfile, IT_INCLUDE_NEXT);
657 /* Subroutine of do_line. Read possible flags after file name. LAST
658 is the last flag seen; 0 if this is the first flag. Return the flag
659 if it is valid, 0 at the end of the directive. Otherwise complain. */
662 read_flag (pfile, last)
668 _cpp_lex_token (pfile, &token);
669 if (token.type == CPP_NUMBER && token.val.str.len == 1)
671 unsigned int flag = token.val.str.text[0] - '0';
673 if (flag > last && flag <= 4
674 && (flag != 4 || last == 3)
675 && (flag != 2 || last == 0))
679 if (token.type != CPP_EOF)
680 cpp_error (pfile, "invalid flag \"%s\" in line directive",
681 cpp_token_as_text (pfile, &token));
685 /* Another subroutine of do_line. Convert a number in STR, of length
686 LEN, to binary; store it in NUMP, and return 0 if the number was
687 well-formed, 1 if not. Temporary, hopefully. */
689 strtoul_for_line (str, len, nump)
694 unsigned long reg = 0;
708 /* Interpret #line command.
709 Note that the filename string (if any) is treated as if it were an
710 include filename. That means no escape handling. */
716 cpp_buffer *buffer = pfile->buffer;
717 enum lc_reason reason = LC_RENAME;
718 unsigned long new_lineno;
722 /* C99 raised the minimum limit on #line numbers. */
723 cap = CPP_OPTION (pfile, c99) ? 2147483647 : 32767;
725 /* #line commands expand macros. */
726 cpp_get_token (pfile, &token);
727 if (token.type != CPP_NUMBER
728 || strtoul_for_line (token.val.str.text, token.val.str.len, &new_lineno))
730 cpp_error (pfile, "\"%s\" after #line is not a positive integer",
731 cpp_token_as_text (pfile, &token));
735 if (CPP_PEDANTIC (pfile) && ! pfile->state.line_extension
736 && (new_lineno == 0 || new_lineno > cap))
737 cpp_pedwarn (pfile, "line number out of range");
739 cpp_get_token (pfile, &token);
740 if (token.type == CPP_STRING)
742 const char *fname = (const char *) token.val.str.text;
744 /* Only accept flags for the # 55 form. */
745 if (! pfile->state.line_extension)
749 int flag = 0, sysp = 0;
751 flag = read_flag (pfile, flag);
755 flag = read_flag (pfile, flag);
760 flag = read_flag (pfile, flag);
765 flag = read_flag (pfile, flag);
767 sysp = 2, read_flag (pfile, flag);
770 if (reason == LC_ENTER)
772 /* Fake a buffer stack for diagnostics. */
773 cpp_push_buffer (pfile, 0, 0, BUF_FAKE, fname);
774 /* Fake an include for cpp_included. */
775 _cpp_fake_include (pfile, fname);
776 buffer = pfile->buffer;
778 else if (reason == LC_LEAVE)
780 if (buffer->type != BUF_FAKE)
781 cpp_warning (pfile, "file \"%s\" left but not entered",
782 buffer->nominal_fname);
785 cpp_pop_buffer (pfile);
786 buffer = pfile->buffer;
787 #ifdef ENABLE_CHECKING
788 if (strcmp (buffer->nominal_fname, fname))
789 cpp_warning (pfile, "expected to return to file \"%s\"",
790 buffer->nominal_fname);
791 if (buffer->lineno + 1 != new_lineno)
792 cpp_warning (pfile, "expected to return to line number %u",
794 if (buffer->sysp != sysp)
795 cpp_warning (pfile, "header flags for \"%s\" have changed",
796 buffer->nominal_fname);
802 buffer->nominal_fname = fname;
804 else if (token.type != CPP_EOF)
806 cpp_error (pfile, "\"%s\" is not a valid filename",
807 cpp_token_as_text (pfile, &token));
811 end_directive (pfile, 1);
812 buffer->lineno = new_lineno - 1;
813 _cpp_do_file_change (pfile, reason);
816 /* Arrange the file_change callback. It is assumed that the next line
817 is given by incrementing buffer->lineno and pfile->line. */
819 _cpp_do_file_change (pfile, reason)
821 enum lc_reason reason;
824 struct line_map *map;
826 buffer = pfile->buffer;
827 map = add_line_map (&pfile->line_maps, reason,
828 pfile->line + 1, buffer->nominal_fname, buffer->lineno + 1);
830 if (pfile->cb.file_change)
835 fc.line = pfile->line + 1;
837 fc.sysp = buffer->sysp;
838 fc.externc = CPP_OPTION (pfile, cplusplus) && buffer->sysp == 2;
840 (*pfile->cb.file_change) (pfile, &fc);
845 * Report a warning or error detected by the program we are
846 * processing. Use the directive's tokens in the error message.
850 do_diagnostic (pfile, code, print_dir)
852 enum error_type code;
855 if (_cpp_begin_message (pfile, code, NULL, 0))
858 fprintf (stderr, "#%s ", pfile->directive->name);
859 pfile->state.prevent_expansion++;
860 cpp_output_line (pfile, stderr);
861 pfile->state.prevent_expansion--;
869 do_diagnostic (pfile, ERROR, 1);
876 /* We want #warning diagnostics to be emitted in system headers too. */
877 do_diagnostic (pfile, WARNING_SYSHDR, 1);
880 /* Report program identification. */
888 cpp_get_token (pfile, &str);
889 if (str.type != CPP_STRING)
890 cpp_error (pfile, "invalid #ident");
891 else if (pfile->cb.ident)
892 (*pfile->cb.ident) (pfile, &str.val.str);
897 /* Pragmata handling. We handle some of these, and pass the rest on
898 to the front end. C99 defines three pragmas and says that no macro
899 expansion is to be performed on them; whether or not macro
900 expansion happens for other pragmas is implementation defined.
901 This implementation never macro-expands the text after #pragma. */
903 /* Sub-handlers for the pragmas needing treatment here.
904 They return 1 if the token buffer is to be popped, 0 if not. */
905 typedef void (*pragma_cb) PARAMS ((cpp_reader *));
908 struct pragma_entry *next;
914 struct pragma_entry *space;
919 cpp_register_pragma (pfile, space, name, handler)
925 struct pragma_entry **x, *new;
931 struct pragma_entry *p = pfile->pragmas;
932 len = strlen (space);
935 if (p->isnspace && p->len == len && !memcmp (p->name, space, len))
942 cpp_ice (pfile, "unknown #pragma namespace %s", space);
947 new = xnew (struct pragma_entry);
949 new->len = strlen (name);
951 new->u.handler = handler;
958 cpp_register_pragma_space (pfile, space)
962 struct pragma_entry *new;
963 const struct pragma_entry *p = pfile->pragmas;
964 size_t len = strlen (space);
968 if (p->isnspace && p->len == len && !memcmp (p->name, space, len))
969 /* Multiple different callers are allowed to register the same
975 new = xnew (struct pragma_entry);
981 new->next = pfile->pragmas;
982 pfile->pragmas = new;
986 _cpp_init_internal_pragmas (pfile)
990 cpp_register_pragma (pfile, 0, "poison", do_pragma_poison);
991 cpp_register_pragma (pfile, 0, "once", do_pragma_once);
994 cpp_register_pragma_space (pfile, "GCC");
996 cpp_register_pragma (pfile, "GCC", "poison", do_pragma_poison);
997 cpp_register_pragma (pfile, "GCC", "system_header", do_pragma_system_header);
998 cpp_register_pragma (pfile, "GCC", "dependency", do_pragma_dependency);
1005 pragma_cb handler = NULL;
1006 const struct pragma_entry *p;
1010 pfile->state.prevent_expansion++;
1011 cpp_start_lookahead (pfile);
1014 cpp_get_token (pfile, &tok);
1015 if (tok.type == CPP_NAME)
1017 const cpp_hashnode *node = tok.val.node;
1018 size_t len = NODE_LEN (node);
1022 if (strlen (p->name) == len
1023 && !memcmp (p->name, NODE_NAME (node), len))
1032 handler = p->u.handler;
1040 cpp_stop_lookahead (pfile, handler != NULL);
1041 pfile->state.prevent_expansion--;
1045 else if (pfile->cb.def_pragma)
1046 (*pfile->cb.def_pragma) (pfile);
1050 do_pragma_once (pfile)
1053 cpp_warning (pfile, "#pragma once is obsolete");
1055 if (pfile->buffer->prev == NULL)
1056 cpp_warning (pfile, "#pragma once in main file");
1058 _cpp_never_reread (pfile->buffer->inc);
1064 do_pragma_poison (pfile)
1067 /* Poison these symbols so that all subsequent usage produces an
1072 pfile->state.poisoned_ok = 1;
1075 _cpp_lex_token (pfile, &tok);
1076 if (tok.type == CPP_EOF)
1078 if (tok.type != CPP_NAME)
1080 cpp_error (pfile, "invalid #pragma GCC poison directive");
1085 if (hp->flags & NODE_POISONED)
1088 if (hp->type == NT_MACRO)
1089 cpp_warning (pfile, "poisoning existing macro \"%s\"", NODE_NAME (hp));
1090 _cpp_free_definition (hp);
1091 hp->flags |= NODE_POISONED | NODE_DIAGNOSTIC;
1093 pfile->state.poisoned_ok = 0;
1096 /* Mark the current header as a system header. This will suppress
1097 some categories of warnings (notably those from -pedantic). It is
1098 intended for use in system libraries that cannot be implemented in
1099 conforming C, but cannot be certain that their headers appear in a
1100 system include directory. To prevent abuse, it is rejected in the
1101 primary source file. */
1103 do_pragma_system_header (pfile)
1106 cpp_buffer *buffer = pfile->buffer;
1108 if (buffer->prev == 0)
1109 cpp_warning (pfile, "#pragma system_header ignored outside include file");
1113 end_directive (pfile, 1);
1114 cpp_make_system_header (pfile, 1, 0);
1118 /* Check the modified date of the current include file against a specified
1119 file. Issue a diagnostic, if the specified file is newer. We use this to
1120 determine if a fixed header should be refixed. */
1122 do_pragma_dependency (pfile)
1125 cpp_token header, msg;
1128 if (parse_include (pfile, &header))
1131 ordering = _cpp_compare_file_date (pfile, &header);
1133 cpp_warning (pfile, "cannot find source %s",
1134 cpp_token_as_text (pfile, &header));
1135 else if (ordering > 0)
1137 cpp_warning (pfile, "current file is older than %s",
1138 cpp_token_as_text (pfile, &header));
1139 cpp_start_lookahead (pfile);
1140 cpp_get_token (pfile, &msg);
1141 cpp_stop_lookahead (pfile, msg.type == CPP_EOF);
1142 if (msg.type != CPP_EOF)
1143 do_diagnostic (pfile, WARNING, 0);
1147 /* Check syntax is "(string-literal)". Returns 0 on success. */
1149 get__Pragma_string (pfile, string)
1155 cpp_get_token (pfile, &paren);
1156 if (paren.type != CPP_OPEN_PAREN)
1159 cpp_get_token (pfile, string);
1160 if (string->type != CPP_STRING && string->type != CPP_WSTRING)
1163 cpp_get_token (pfile, &paren);
1164 return paren.type != CPP_CLOSE_PAREN;
1167 /* Returns a malloced buffer containing a destringized cpp_string by
1168 removing the first \ of \" and \\ sequences. */
1169 static unsigned char *
1170 destringize (in, len)
1171 const cpp_string *in;
1174 const unsigned char *src, *limit;
1175 unsigned char *dest, *result;
1177 dest = result = (unsigned char *) xmalloc (in->len);
1178 for (src = in->text, limit = src + in->len; src < limit;)
1180 /* We know there is a character following the backslash. */
1181 if (*src == '\\' && (src[1] == '\\' || src[1] == '"'))
1186 *len = dest - result;
1191 _cpp_do__Pragma (pfile)
1195 unsigned char *buffer;
1198 if (get__Pragma_string (pfile, &string))
1200 cpp_error (pfile, "_Pragma takes a parenthesized string literal");
1204 buffer = destringize (&string.val.str, &len);
1205 run_directive (pfile, T_PRAGMA, BUF_PRAGMA, (char *) buffer, len);
1206 free ((PTR) buffer);
1209 /* Just ignore #sccs, on systems where we define it at all. */
1210 #ifdef SCCS_DIRECTIVE
1213 cpp_reader *pfile ATTRIBUTE_UNUSED;
1224 if (! pfile->state.skipping)
1226 const cpp_hashnode *node = lex_macro_node (pfile);
1229 skip = node->type != NT_MACRO;
1235 push_conditional (pfile, skip, T_IFDEF, 0);
1243 const cpp_hashnode *node = 0;
1245 if (! pfile->state.skipping)
1247 node = lex_macro_node (pfile);
1249 skip = node->type == NT_MACRO;
1255 push_conditional (pfile, skip, T_IFNDEF, node);
1258 /* _cpp_parse_expr puts a macro in a "#if !defined ()" expression in
1259 pfile->mi_ind_cmacro so we can handle multiple-include
1260 optimisations. If macro expansion occurs in the expression, we
1261 cannot treat it as a controlling conditional, since the expansion
1262 could change in the future. That is handled by cpp_get_token. */
1270 if (! pfile->state.skipping)
1271 skip = _cpp_parse_expr (pfile) == 0;
1273 push_conditional (pfile, skip, T_IF, pfile->mi_ind_cmacro);
1276 /* Flip skipping state if appropriate and continue without changing
1277 if_stack; this is so that the error message for missing #endif's
1278 etc. will point to the original #if. */
1284 cpp_buffer *buffer = pfile->buffer;
1285 struct if_stack *ifs = buffer->if_stack;
1288 cpp_error (pfile, "#else without #if");
1291 if (ifs->type == T_ELSE)
1293 cpp_error (pfile, "#else after #else");
1294 cpp_error_with_line (pfile, ifs->pos.line, ifs->pos.col,
1295 "the conditional began here");
1299 /* Skip any future (erroneous) #elses or #elifs. */
1300 pfile->state.skipping = ifs->skip_elses;
1301 ifs->skip_elses = true;
1303 /* Invalidate any controlling macro. */
1306 /* Only check EOL if was not originally skipping. */
1307 if (!ifs->was_skipping)
1312 /* handle a #elif directive by not changing if_stack either. see the
1313 comment above do_else. */
1319 cpp_buffer *buffer = pfile->buffer;
1320 struct if_stack *ifs = buffer->if_stack;
1323 cpp_error (pfile, "#elif without #if");
1326 if (ifs->type == T_ELSE)
1328 cpp_error (pfile, "#elif after #else");
1329 cpp_error_with_line (pfile, ifs->pos.line, ifs->pos.col,
1330 "the conditional began here");
1334 /* Only evaluate this if we aren't skipping elses. During
1335 evaluation, set skipping to false to get lexer warnings. */
1336 if (ifs->skip_elses)
1337 pfile->state.skipping = 1;
1340 pfile->state.skipping = 0;
1341 pfile->state.skipping = ! _cpp_parse_expr (pfile);
1342 ifs->skip_elses = ! pfile->state.skipping;
1345 /* Invalidate any controlling macro. */
1350 /* #endif pops the if stack and resets pfile->state.skipping. */
1356 cpp_buffer *buffer = pfile->buffer;
1357 struct if_stack *ifs = buffer->if_stack;
1360 cpp_error (pfile, "#endif without #if");
1363 /* Only check EOL if was not originally skipping. */
1364 if (!ifs->was_skipping)
1367 /* If potential control macro, we go back outside again. */
1368 if (ifs->next == 0 && ifs->mi_cmacro)
1370 pfile->mi_valid = true;
1371 pfile->mi_cmacro = ifs->mi_cmacro;
1374 buffer->if_stack = ifs->next;
1375 pfile->state.skipping = ifs->was_skipping;
1376 obstack_free (&pfile->buffer_ob, ifs);
1380 /* Push an if_stack entry and set pfile->state.skipping accordingly.
1381 If this is a #if or #ifndef, CMACRO is a potentially controlling
1382 macro - we need to check here that we are at the top of the file. */
1385 push_conditional (pfile, skip, type, cmacro)
1389 const cpp_hashnode *cmacro;
1391 struct if_stack *ifs;
1392 cpp_buffer *buffer = pfile->buffer;
1394 ifs = xobnew (&pfile->buffer_ob, struct if_stack);
1395 ifs->pos = pfile->directive_pos;
1396 ifs->next = buffer->if_stack;
1397 ifs->skip_elses = pfile->state.skipping || !skip;
1398 ifs->was_skipping = pfile->state.skipping;
1400 /* This condition is effectively a test for top-of-file. */
1401 if (pfile->mi_valid && pfile->mi_cmacro == 0)
1402 ifs->mi_cmacro = cmacro;
1406 pfile->state.skipping = skip;
1407 buffer->if_stack = ifs;
1410 /* Read the tokens of the answer into the macro pool. Only commit the
1411 memory if we intend it as permanent storage, i.e. the #assert case.
1412 Returns 0 on success. */
1415 parse_answer (pfile, answerp, type)
1417 struct answer **answerp;
1420 cpp_token paren, *token;
1421 struct answer *answer;
1423 if (POOL_FRONT (&pfile->macro_pool) + sizeof (struct answer) >
1424 POOL_LIMIT (&pfile->macro_pool))
1425 _cpp_next_chunk (&pfile->macro_pool, sizeof (struct answer), 0);
1426 answer = (struct answer *) POOL_FRONT (&pfile->macro_pool);
1429 /* In a conditional, it is legal to not have an open paren. We
1430 should save the following token in this case. */
1432 cpp_start_lookahead (pfile);
1433 cpp_get_token (pfile, &paren);
1435 cpp_stop_lookahead (pfile, paren.type == CPP_OPEN_PAREN);
1437 /* If not a paren, see if we're OK. */
1438 if (paren.type != CPP_OPEN_PAREN)
1440 /* In a conditional no answer is a test for any answer. It
1441 could be followed by any token. */
1445 /* #unassert with no answer is valid - it removes all answers. */
1446 if (type == T_UNASSERT && paren.type == CPP_EOF)
1449 cpp_error (pfile, "missing '(' after predicate");
1455 token = &answer->first[answer->count];
1456 /* Check we have room for the token. */
1457 if ((unsigned char *) (token + 1) >= POOL_LIMIT (&pfile->macro_pool))
1459 _cpp_next_chunk (&pfile->macro_pool, sizeof (cpp_token),
1460 (unsigned char **) &answer);
1461 token = &answer->first[answer->count];
1464 cpp_get_token (pfile, token);
1465 if (token->type == CPP_CLOSE_PAREN)
1468 if (token->type == CPP_EOF)
1470 cpp_error (pfile, "missing ')' to complete answer");
1476 if (answer->count == 0)
1478 cpp_error (pfile, "predicate's answer is empty");
1482 /* Drop whitespace at start. */
1483 answer->first->flags &= ~PREV_WHITE;
1486 if (type == T_ASSERT || type == T_UNASSERT)
1491 /* Parses an assertion, returning a pointer to the hash node of the
1492 predicate, or 0 on error. If an answer was supplied, it is placed
1493 in ANSWERP, otherwise it is set to 0. */
1494 static cpp_hashnode *
1495 parse_assertion (pfile, answerp, type)
1497 struct answer **answerp;
1500 cpp_hashnode *result = 0;
1501 cpp_token predicate;
1503 /* We don't expand predicates or answers. */
1504 pfile->state.prevent_expansion++;
1507 cpp_get_token (pfile, &predicate);
1508 if (predicate.type == CPP_EOF)
1509 cpp_error (pfile, "assertion without predicate");
1510 else if (predicate.type != CPP_NAME)
1511 cpp_error (pfile, "predicate must be an identifier");
1512 else if (parse_answer (pfile, answerp, type) == 0)
1514 unsigned int len = NODE_LEN (predicate.val.node);
1515 unsigned char *sym = alloca (len + 1);
1517 /* Prefix '#' to get it out of macro namespace. */
1519 memcpy (sym + 1, NODE_NAME (predicate.val.node), len);
1520 result = cpp_lookup (pfile, sym, len + 1);
1523 pfile->state.prevent_expansion--;
1527 /* Returns a pointer to the pointer to the answer in the answer chain,
1528 or a pointer to NULL if the answer is not in the chain. */
1529 static struct answer **
1530 find_answer (node, candidate)
1532 const struct answer *candidate;
1535 struct answer **result;
1537 for (result = &node->value.answers; *result; result = &(*result)->next)
1539 struct answer *answer = *result;
1541 if (answer->count == candidate->count)
1543 for (i = 0; i < answer->count; i++)
1544 if (! _cpp_equiv_tokens (&answer->first[i], &candidate->first[i]))
1547 if (i == answer->count)
1555 /* Test an assertion within a preprocessor conditional. Returns
1556 non-zero on failure, zero on success. On success, the result of
1557 the test is written into VALUE. */
1559 _cpp_test_assertion (pfile, value)
1563 struct answer *answer;
1566 node = parse_assertion (pfile, &answer, T_IF);
1568 *value = (node->type == NT_ASSERTION &&
1569 (answer == 0 || *find_answer (node, answer) != 0));
1571 /* We don't commit the memory for the answer - it's temporary only. */
1579 struct answer *new_answer;
1582 node = parse_assertion (pfile, &new_answer, T_ASSERT);
1585 /* Place the new answer in the answer list. First check there
1586 is not a duplicate. */
1587 new_answer->next = 0;
1588 if (node->type == NT_ASSERTION)
1590 if (*find_answer (node, new_answer))
1592 cpp_warning (pfile, "\"%s\" re-asserted", NODE_NAME (node) + 1);
1595 new_answer->next = node->value.answers;
1597 node->type = NT_ASSERTION;
1598 node->value.answers = new_answer;
1599 POOL_COMMIT (&pfile->macro_pool, (sizeof (struct answer)
1600 + (new_answer->count - 1)
1601 * sizeof (cpp_token)));
1610 struct answer *answer;
1612 node = parse_assertion (pfile, &answer, T_UNASSERT);
1613 /* It isn't an error to #unassert something that isn't asserted. */
1614 if (node && node->type == NT_ASSERTION)
1618 struct answer **p = find_answer (node, answer), *temp;
1620 /* Remove the answer from the list. */
1625 /* Did we free the last answer? */
1626 if (node->value.answers == 0)
1627 node->type = NT_VOID;
1630 _cpp_free_definition (node);
1633 /* We don't commit the memory for the answer - it's temporary only. */
1636 /* These are for -D, -U, -A. */
1638 /* Process the string STR as if it appeared as the body of a #define.
1639 If STR is just an identifier, define it with value 1.
1640 If STR has anything after the identifier, then it should
1641 be identifier=definition. */
1644 cpp_define (pfile, str)
1651 /* Copy the entire option so we can modify it.
1652 Change the first "=" in the string to a space. If there is none,
1653 tack " 1" on the end. */
1655 /* Length including the null. */
1656 count = strlen (str);
1657 buf = (char *) alloca (count + 2);
1658 memcpy (buf, str, count);
1660 p = strchr (str, '=');
1669 run_directive (pfile, T_DEFINE, BUF_CL_OPTION, buf, count);
1672 /* Slight variant of the above for use by initialize_builtins. */
1674 _cpp_define_builtin (pfile, str)
1678 run_directive (pfile, T_DEFINE, BUF_BUILTIN, str, strlen (str));
1681 /* Process MACRO as if it appeared as the body of an #undef. */
1683 cpp_undef (pfile, macro)
1687 run_directive (pfile, T_UNDEF, BUF_CL_OPTION, macro, strlen (macro));
1690 /* Process the string STR as if it appeared as the body of a #assert. */
1692 cpp_assert (pfile, str)
1696 handle_assertion (pfile, str, T_ASSERT);
1699 /* Process STR as if it appeared as the body of an #unassert. */
1701 cpp_unassert (pfile, str)
1705 handle_assertion (pfile, str, T_UNASSERT);
1708 /* Common code for cpp_assert (-A) and cpp_unassert (-A-). */
1710 handle_assertion (pfile, str, type)
1715 size_t count = strlen (str);
1716 const char *p = strchr (str, '=');
1720 /* Copy the entire option so we can modify it. Change the first
1721 "=" in the string to a '(', and tack a ')' on the end. */
1722 char *buf = (char *) alloca (count + 1);
1724 memcpy (buf, str, count);
1730 run_directive (pfile, type, BUF_CL_OPTION, str, count);
1733 /* The number of errors for a given reader. */
1738 return pfile->errors;
1741 /* The options structure. */
1743 cpp_get_options (pfile)
1746 return &pfile->opts;
1749 /* The callbacks structure. */
1751 cpp_get_callbacks (pfile)
1757 /* The line map set. */
1759 cpp_get_line_maps (pfile)
1762 return &pfile->line_maps;
1765 /* Copy the given callbacks structure to our own. */
1767 cpp_set_callbacks (pfile, cb)
1774 /* Push a new buffer on the buffer stack. Returns the new buffer; it
1775 doesn't fail. It does not generate a file change call back; that
1776 is the responsibility of the caller. */
1778 cpp_push_buffer (pfile, buffer, len, type, filename)
1780 const U_CHAR *buffer;
1782 enum cpp_buffer_type type;
1783 const char *filename;
1785 cpp_buffer *new = xobnew (&pfile->buffer_ob, cpp_buffer);
1787 if (type == BUF_FAKE)
1789 /* A copy of the current buffer, just with a new name and type. */
1790 memcpy (new, pfile->buffer, sizeof (cpp_buffer));
1791 new->type = BUF_FAKE;
1795 if (type == BUF_BUILTIN)
1796 filename = _("<builtin>");
1797 else if (type == BUF_CL_OPTION)
1798 filename = _("<command line>");
1799 else if (type == BUF_PRAGMA)
1800 filename = "<_Pragma>";
1802 /* Clears, amongst other things, if_stack and mi_cmacro. */
1803 memset (new, 0, sizeof (cpp_buffer));
1805 new->line_base = new->buf = new->cur = buffer;
1806 new->rlimit = buffer + len;
1809 /* No read ahead or extra char initially. */
1810 new->read_ahead = EOF;
1811 new->extra_char = EOF;
1813 /* Preprocessed files, builtins, _Pragma and command line
1814 options don't do trigraph and escaped newline processing. */
1815 new->from_stage3 = type != BUF_FILE || CPP_OPTION (pfile, preprocessed);
1817 pfile->lexer_pos.output_line = 1;
1820 if (*filename == '\0')
1821 new->nominal_fname = _("<stdin>");
1823 new->nominal_fname = filename;
1825 new->prev = pfile->buffer;
1827 new->include_stack_listed = 0;
1830 pfile->state.next_bol = 1;
1831 pfile->buffer_stack_depth++;
1832 pfile->buffer = new;
1837 /* If called from do_line, pops a single buffer. Otherwise pops all
1838 buffers until a real file is reached. Generates appropriate
1841 cpp_pop_buffer (pfile)
1845 struct if_stack *ifs;
1849 buffer = pfile->buffer;
1850 /* Walk back up the conditional stack till we reach its level at
1851 entry to this file, issuing error messages. */
1852 for (ifs = buffer->if_stack; ifs; ifs = ifs->next)
1853 cpp_error_with_line (pfile, ifs->pos.line, ifs->pos.col,
1854 "unterminated #%s", dtable[ifs->type].name);
1856 if (buffer->type == BUF_FAKE)
1857 buffer->prev->cur = buffer->cur;
1858 else if (buffer->type == BUF_FILE)
1859 _cpp_pop_file_buffer (pfile, buffer);
1861 pfile->buffer = buffer->prev;
1862 pfile->buffer_stack_depth--;
1864 /* Callbacks only generated for faked or real files. */
1865 if (buffer->type != BUF_FILE && buffer->type != BUF_FAKE)
1868 /* No callback for EOF of last file. */
1872 /* do_line does its own call backs. */
1873 pfile->buffer->include_stack_listed = 0;
1874 if (pfile->directive == &dtable[T_LINE])
1877 pfile->line--; /* We have a '\n' at the end of #include. */
1878 _cpp_do_file_change (pfile, LC_LEAVE);
1879 if (pfile->buffer->type == BUF_FILE)
1882 cpp_warning (pfile, "file \"%s\" entered but not left",
1883 buffer->nominal_fname);
1886 obstack_free (&pfile->buffer_ob, buffer);
1887 return pfile->buffer;
1891 _cpp_init_directives (pfile)
1897 /* Register the directives. */
1898 for (i = 0; i < (unsigned int) N_DIRECTIVES; i++)
1900 node = cpp_lookup (pfile, dtable[i].name, dtable[i].length);
1901 node->directive_index = i + 1;