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 unsigned char was_skipping; /* Value of pfile->skipping before this if. */
47 int type; /* type of last directive seen in this group */
50 /* Values for the origin field of struct directive. KANDR directives
51 come from traditional (K&R) C. STDC89 directives come from the
52 1989 C standard. EXTENSION directives are extensions. */
57 /* Values for the flags field of struct directive. COND indicates a
58 conditional; IF_COND an opening conditional. INCL means to treat
59 "..." and <...> as q-char and h-char sequences respectively. IN_I
60 means this directive should be handled even if -fpreprocessed is in
61 effect (these are the directives with callback hooks). */
63 #define IF_COND (1 << 1)
67 /* Defines one #-directive, including how to handle it. */
68 typedef void (*directive_handler) PARAMS ((cpp_reader *));
69 typedef struct directive directive;
72 directive_handler handler; /* Function to handle directive. */
73 const U_CHAR *name; /* Name of directive. */
74 unsigned short length; /* Length of name. */
75 unsigned char origin; /* Origin of directive. */
76 unsigned char flags; /* Flags describing this directive. */
79 /* Forward declarations. */
81 static void skip_rest_of_line PARAMS ((cpp_reader *));
82 static void check_eol PARAMS ((cpp_reader *));
83 static void start_directive PARAMS ((cpp_reader *));
84 static void end_directive PARAMS ((cpp_reader *, int));
85 static void run_directive PARAMS ((cpp_reader *, int,
87 const char *, size_t));
88 static int glue_header_name PARAMS ((cpp_reader *, cpp_token *));
89 static int parse_include PARAMS ((cpp_reader *, cpp_token *));
90 static void push_conditional PARAMS ((cpp_reader *, int, int,
91 const cpp_hashnode *));
92 static unsigned int read_flag PARAMS ((cpp_reader *, unsigned int));
93 static int strtoul_for_line PARAMS ((const U_CHAR *, unsigned int,
95 static void do_diagnostic PARAMS ((cpp_reader *, enum error_type, int));
96 static cpp_hashnode *lex_macro_node PARAMS ((cpp_reader *));
97 static void do_include_common PARAMS ((cpp_reader *, enum include_type));
98 static void do_pragma_once PARAMS ((cpp_reader *));
99 static void do_pragma_poison PARAMS ((cpp_reader *));
100 static void do_pragma_system_header PARAMS ((cpp_reader *));
101 static void do_pragma_dependency PARAMS ((cpp_reader *));
102 static int get__Pragma_string PARAMS ((cpp_reader *, cpp_token *));
103 static unsigned char *destringize PARAMS ((const cpp_string *,
105 static int parse_answer PARAMS ((cpp_reader *, struct answer **, int));
106 static cpp_hashnode *parse_assertion PARAMS ((cpp_reader *, struct answer **,
108 static struct answer ** find_answer PARAMS ((cpp_hashnode *,
109 const struct answer *));
110 static void handle_assertion PARAMS ((cpp_reader *, const char *, int));
112 /* This is the table of directive handlers. It is ordered by
113 frequency of occurrence; the numbers at the end are directive
114 counts from all the source code I have lying around (egcs and libc
115 CVS as of 1999-05-18, plus grub-0.5.91, linux-2.2.9, and
116 pcmcia-cs-3.0.9). This is no longer important as directive lookup
117 is now O(1). All extensions other than #warning and #include_next
118 are deprecated. The name is where the extension appears to have
121 #define DIRECTIVE_TABLE \
122 D(define, T_DEFINE = 0, KANDR, IN_I) /* 270554 */ \
123 D(include, T_INCLUDE, KANDR, INCL) /* 52262 */ \
124 D(endif, T_ENDIF, KANDR, COND) /* 45855 */ \
125 D(ifdef, T_IFDEF, KANDR, COND | IF_COND) /* 22000 */ \
126 D(if, T_IF, KANDR, COND | IF_COND) /* 18162 */ \
127 D(else, T_ELSE, KANDR, COND) /* 9863 */ \
128 D(ifndef, T_IFNDEF, KANDR, COND | IF_COND) /* 9675 */ \
129 D(undef, T_UNDEF, KANDR, IN_I) /* 4837 */ \
130 D(line, T_LINE, KANDR, IN_I) /* 2465 */ \
131 D(elif, T_ELIF, STDC89, COND) /* 610 */ \
132 D(error, T_ERROR, STDC89, 0) /* 475 */ \
133 D(pragma, T_PRAGMA, STDC89, IN_I) /* 195 */ \
134 D(warning, T_WARNING, EXTENSION, 0) /* 22 */ \
135 D(include_next, T_INCLUDE_NEXT, EXTENSION, INCL) /* 19 */ \
136 D(ident, T_IDENT, EXTENSION, IN_I) /* 11 */ \
137 D(import, T_IMPORT, EXTENSION, INCL) /* 0 ObjC */ \
138 D(assert, T_ASSERT, EXTENSION, 0) /* 0 SVR4 */ \
139 D(unassert, T_UNASSERT, EXTENSION, 0) /* 0 SVR4 */ \
140 SCCS_ENTRY /* 0 SVR4? */
142 /* #sccs is not always recognized. */
143 #ifdef SCCS_DIRECTIVE
144 # define SCCS_ENTRY D(sccs, T_SCCS, EXTENSION, 0)
146 # define SCCS_ENTRY /* nothing */
149 /* Use the table to generate a series of prototypes, an enum for the
150 directive names, and an array of directive handlers. */
152 /* The directive-processing functions are declared to return int
153 instead of void, because some old compilers have trouble with
154 pointers to functions returning void. */
156 /* Don't invoke CONCAT2 with any whitespace or K&R cc will fail. */
157 #define D(name, t, o, f) static void CONCAT2(do_,name) PARAMS ((cpp_reader *));
161 #define D(n, tag, o, f) tag,
169 /* Don't invoke CONCAT2 with any whitespace or K&R cc will fail. */
170 #define D(name, t, origin, flags) \
171 { CONCAT2(do_,name), (const U_CHAR *) STRINGX(name), \
172 sizeof STRINGX(name) - 1, origin, flags },
173 static const directive dtable[] =
178 #undef DIRECTIVE_TABLE
180 /* Skip any remaining tokens in a directive. */
182 skip_rest_of_line (pfile)
187 /* Discard all input lookaheads. */
188 while (pfile->la_read)
189 _cpp_release_lookahead (pfile);
191 /* Discard all stacked contexts. */
192 while (pfile->context != &pfile->base_context)
193 _cpp_pop_context (pfile);
195 /* Sweep up all tokens remaining on the line. */
196 pfile->state.prevent_expansion++;
197 while (!pfile->state.next_bol)
198 _cpp_lex_token (pfile, &token);
199 pfile->state.prevent_expansion--;
202 /* Ensure there are no stray tokens at the end of a directive. */
207 if (!pfile->state.next_bol)
211 _cpp_lex_token (pfile, &token);
212 if (token.type != CPP_EOF)
213 cpp_pedwarn (pfile, "extra tokens at end of #%s directive",
214 pfile->directive->name);
218 /* Called when entering a directive, _Pragma or command-line directive. */
220 start_directive (pfile)
223 cpp_buffer *buffer = pfile->buffer;
225 /* Setup in-directive state. */
226 pfile->state.in_directive = 1;
227 pfile->state.save_comments = 0;
229 /* Some handlers need the position of the # for diagnostics. */
230 pfile->directive_pos = pfile->lexer_pos;
232 /* Don't save directive tokens for external clients. */
233 pfile->la_saved = pfile->la_write;
236 /* Turn off skipping. */
237 buffer->was_skipping = pfile->skipping;
241 /* Called when leaving a directive, _Pragma or command-line directive. */
243 end_directive (pfile, skip_line)
247 cpp_buffer *buffer = pfile->buffer;
249 /* Restore pfile->skipping before skip_rest_of_line, so that e.g.
250 __VA_ARGS__ in the rest of the directive doesn't warn. */
251 pfile->skipping = buffer->was_skipping;
253 /* We don't skip for an assembler #. */
255 skip_rest_of_line (pfile);
258 pfile->la_write = pfile->la_saved;
259 pfile->state.save_comments = ! CPP_OPTION (pfile, discard_comments);
260 pfile->state.in_directive = 0;
261 pfile->state.angled_headers = 0;
262 pfile->state.line_extension = 0;
263 pfile->directive = 0;
266 /* Check if a token's name matches that of a known directive. Put in
267 this file to save exporting dtable and other unneeded information. */
269 _cpp_handle_directive (pfile, indented)
273 cpp_buffer *buffer = pfile->buffer;
274 const directive *dir = 0;
278 start_directive (pfile);
280 /* Lex the directive name directly. */
281 _cpp_lex_token (pfile, &dname);
283 if (dname.type == CPP_NAME)
285 unsigned int index = dname.val.node->directive_index;
287 dir = &dtable[index - 1];
289 else if (dname.type == CPP_NUMBER)
291 /* # followed by a number is equivalent to #line. Do not
292 recognize this form in assembly language source files or
293 skipped conditional groups. Complain about this form if
294 we're being pedantic, but not if this is regurgitated input
295 (preprocessed or fed back in by the C++ frontend). */
296 if (! buffer->was_skipping && CPP_OPTION (pfile, lang) != CLK_ASM)
298 dir = &dtable[T_LINE];
299 pfile->state.line_extension = 1;
300 _cpp_push_token (pfile, &dname, &pfile->directive_pos);
301 if (CPP_PEDANTIC (pfile) && ! CPP_OPTION (pfile, preprocessed))
302 cpp_pedwarn (pfile, "# followed by integer");
306 pfile->directive = dir;
309 /* Make sure we lex headers correctly, whether skipping or not. */
310 pfile->state.angled_headers = dir->flags & INCL;
312 /* If we are rescanning preprocessed input, only directives tagged
313 with IN_I are honored, and the warnings below are suppressed. */
314 if (! CPP_OPTION (pfile, preprocessed) || dir->flags & IN_I)
316 /* Traditionally, a directive is ignored unless its # is in
317 column 1. Therefore in code intended to work with K+R
318 compilers, directives added by C89 must have their #
319 indented, and directives present in traditional C must
320 not. This is true even of directives in skipped
321 conditional blocks. */
322 if (CPP_WTRADITIONAL (pfile))
324 if (dir == &dtable[T_ELIF])
326 "suggest not using #elif in traditional C");
327 else if (indented && dir->origin == KANDR)
329 "traditional C ignores #%s with the # indented",
331 else if (!indented && dir->origin != KANDR)
333 "suggest hiding #%s from traditional C with an indented #",
337 /* If we are skipping a failed conditional group, all
338 non-conditional directives are ignored. */
339 if (! buffer->was_skipping || (dir->flags & COND))
341 /* Issue -pedantic warnings for extensions. */
342 if (CPP_PEDANTIC (pfile) && dir->origin == EXTENSION)
343 cpp_pedwarn (pfile, "#%s is a GCC extension", dir->name);
345 /* If we have a directive that is not an opening
346 conditional, invalidate any control macro. */
347 if (! (dir->flags & IF_COND))
348 pfile->mi_state = MI_FAILED;
350 (*dir->handler) (pfile);
354 else if (dname.type != CPP_EOF && ! buffer->was_skipping)
356 /* An unknown directive. Don't complain about it in assembly
357 source: we don't know where the comments are, and # may
358 introduce assembler pseudo-ops. Don't complain about invalid
359 directives in skipped conditional groups (6.10 p4). */
360 if (CPP_OPTION (pfile, lang) == CLK_ASM)
362 /* Output the # and lookahead token for the assembler. */
363 _cpp_push_token (pfile, &dname, &pfile->directive_pos);
367 cpp_error (pfile, "invalid preprocessing directive #%s",
368 cpp_token_as_text (pfile, &dname));
371 end_directive (pfile, skip);
375 /* Directive handler wrapper used by the command line option
378 run_directive (pfile, dir_no, type, buf, count)
381 enum cpp_buffer_type type;
385 unsigned int output_line = pfile->lexer_pos.output_line;
388 buffer = cpp_push_buffer (pfile, (const U_CHAR *) buf, count, type, 0);
390 if (dir_no == T_PRAGMA)
392 /* A kludge to avoid line markers for _Pragma. */
393 pfile->lexer_pos.output_line = output_line;
394 /* Avoid interpretation of directives in a _Pragma string. */
395 pfile->state.next_bol = 0;
398 start_directive (pfile);
399 pfile->state.prevent_expansion++;
400 (void) (*dtable[dir_no].handler) (pfile);
401 pfile->state.prevent_expansion--;
403 end_directive (pfile, 1);
405 cpp_pop_buffer (pfile);
408 /* Checks for validity the macro name in #define, #undef, #ifdef and
409 #ifndef directives. */
410 static cpp_hashnode *
411 lex_macro_node (pfile)
416 /* Lex the macro name directly. */
417 _cpp_lex_token (pfile, &token);
419 /* The token immediately after #define must be an identifier. That
420 identifier is not allowed to be "defined". See predefined macro
421 names (6.10.8.4). In C++, it is not allowed to be any of the
422 <iso646.h> macro names (which are keywords in C++) either. */
424 if (token.type != CPP_NAME)
426 if (token.type == CPP_EOF)
427 cpp_error (pfile, "no macro name given in #%s directive",
428 pfile->directive->name);
429 else if (token.flags & NAMED_OP)
431 "\"%s\" cannot be used as a macro name as it is an operator in C++",
432 token.val.node->name);
434 cpp_error (pfile, "macro names must be identifiers");
438 cpp_hashnode *node = token.val.node;
440 /* In Objective C, some keywords begin with '@', but general
441 identifiers do not, and you're not allowed to #define them. */
442 if (node == pfile->spec_nodes.n_defined || node->name[0] == '@')
443 cpp_error (pfile, "\"%s\" cannot be used as a macro name", node->name);
444 else if (!(node->flags & NODE_POISONED))
451 /* Process a #define directive. Most work is done in cppmacro.c. */
456 cpp_hashnode *node = lex_macro_node (pfile);
460 if (_cpp_create_definition (pfile, node))
461 if (pfile->cb.define)
462 (*pfile->cb.define) (pfile, node);
466 /* Handle #undef. Marks the identifier NT_VOID in the hash table. */
471 cpp_hashnode *node = lex_macro_node (pfile);
473 /* 6.10.3.5 paragraph 2: [#undef] is ignored if the specified identifier
474 is not currently defined as a macro name. */
475 if (node && node->type == NT_MACRO)
478 (*pfile->cb.undef) (pfile, node);
480 if (node->flags & NODE_WARN)
481 cpp_warning (pfile, "undefining \"%s\"", node->name);
483 _cpp_free_definition (node);
488 /* Helper routine used by parse_include. Reinterpret the current line
489 as an h-char-sequence (< ... >); we are looking at the first token
490 after the <. Returns zero on success. */
492 glue_header_name (pfile, header)
497 unsigned char *buffer, *token_mem;
498 size_t len, total_len = 0, capacity = 1024;
500 /* To avoid lexed tokens overwriting our glued name, we can only
501 allocate from the string pool once we've lexed everything. */
503 buffer = (unsigned char *) xmalloc (capacity);
506 cpp_get_token (pfile, &token);
508 if (token.type == CPP_GREATER || token.type == CPP_EOF)
511 len = cpp_token_len (&token);
512 if (total_len + len > capacity)
514 capacity = (capacity + len) * 2;
515 buffer = (unsigned char *) xrealloc (buffer, capacity);
518 if (token.flags & PREV_WHITE)
519 buffer[total_len++] = ' ';
521 total_len = cpp_spell_token (pfile, &token, &buffer[total_len]) - buffer;
524 if (token.type == CPP_EOF)
525 cpp_error (pfile, "missing terminating > character");
528 token_mem = _cpp_pool_alloc (&pfile->ident_pool, total_len + 1);
529 memcpy (token_mem, buffer, total_len);
530 token_mem[total_len] = '\0';
532 header->type = CPP_HEADER_NAME;
533 header->flags &= ~PREV_WHITE;
534 header->val.str.len = total_len;
535 header->val.str.text = token_mem;
539 return token.type == CPP_EOF;
542 /* Parse the header name of #include, #include_next, #import and
543 #pragma dependency. Returns zero on success. */
545 parse_include (pfile, header)
549 int is_pragma = pfile->directive == &dtable[T_PRAGMA];
550 const unsigned char *dir;
553 dir = U"pragma dependency";
555 dir = pfile->directive->name;
557 /* Allow macro expansion. */
558 cpp_get_token (pfile, header);
559 if (header->type != CPP_STRING && header->type != CPP_HEADER_NAME)
561 if (header->type != CPP_LESS)
563 cpp_error (pfile, "#%s expects \"FILENAME\" or <FILENAME>", dir);
566 if (glue_header_name (pfile, header))
570 if (header->val.str.len == 0)
572 cpp_error (pfile, "empty file name in #%s", dir);
579 /* Get out of macro context, if we are. */
580 skip_rest_of_line (pfile);
581 if (pfile->cb.include)
582 (*pfile->cb.include) (pfile, dir, header);
588 /* Handle #include, #include_next and #import. */
590 do_include_common (pfile, type)
592 enum include_type type;
596 if (!parse_include (pfile, &header))
598 /* Prevent #include recursion. */
599 if (pfile->buffer_stack_depth >= CPP_STACK_MAX)
600 cpp_fatal (pfile, "#include nested too deeply");
601 else if (pfile->context->prev)
602 cpp_ice (pfile, "attempt to push file buffer with contexts stacked");
605 /* For #include_next, if this is the primary source file,
606 warn and use the normal search logic. */
607 if (type == IT_INCLUDE_NEXT && ! pfile->buffer->prev)
609 cpp_warning (pfile, "#include_next in primary source file");
613 _cpp_execute_include (pfile, &header, type);
622 do_include_common (pfile, IT_INCLUDE);
629 if (!pfile->import_warning && CPP_OPTION (pfile, warn_import))
631 pfile->import_warning = 1;
633 "#import is obsolete, use an #ifndef wrapper in the header file");
636 do_include_common (pfile, IT_IMPORT);
640 do_include_next (pfile)
643 do_include_common (pfile, IT_INCLUDE_NEXT);
646 /* Subroutine of do_line. Read possible flags after file name. LAST
647 is the last flag seen; 0 if this is the first flag. Return the flag
648 if it is valid, 0 at the end of the directive. Otherwise complain. */
651 read_flag (pfile, last)
657 _cpp_lex_token (pfile, &token);
658 if (token.type == CPP_NUMBER && token.val.str.len == 1)
660 unsigned int flag = token.val.str.text[0] - '0';
662 if (flag > last && flag <= 4
663 && (flag != 4 || last == 3)
664 && (flag != 2 || last == 0))
668 if (token.type != CPP_EOF)
669 cpp_error (pfile, "invalid flag \"%s\" in line directive",
670 cpp_token_as_text (pfile, &token));
674 /* Another subroutine of do_line. Convert a number in STR, of length
675 LEN, to binary; store it in NUMP, and return 0 if the number was
676 well-formed, 1 if not. Temporary, hopefully. */
678 strtoul_for_line (str, len, nump)
683 unsigned long reg = 0;
697 /* Interpret #line command.
698 Note that the filename string (if any) is treated as if it were an
699 include filename. That means no escape handling. */
705 cpp_buffer *buffer = pfile->buffer;
706 const char *filename = buffer->nominal_fname;
707 unsigned int lineno = buffer->lineno;
708 enum cpp_fc_reason reason = FC_RENAME;
709 unsigned long new_lineno;
713 /* C99 raised the minimum limit on #line numbers. */
714 cap = CPP_OPTION (pfile, c99) ? 2147483647 : 32767;
716 /* #line commands expand macros. */
717 cpp_get_token (pfile, &token);
718 if (token.type != CPP_NUMBER
719 || strtoul_for_line (token.val.str.text, token.val.str.len, &new_lineno))
721 cpp_error (pfile, "\"%s\" after #line is not a positive integer",
722 cpp_token_as_text (pfile, &token));
726 if (CPP_PEDANTIC (pfile) && (new_lineno == 0 || new_lineno > cap))
727 cpp_pedwarn (pfile, "line number out of range");
729 cpp_get_token (pfile, &token);
730 if (token.type == CPP_STRING)
733 unsigned int len = token.val.str.len + 1;
735 fname = (char *) _cpp_pool_alloc (&pfile->ident_pool, len);
736 memcpy (fname, token.val.str.text, len);
737 _cpp_simplify_pathname (fname);
739 /* Only accept flags for the # 55 form. */
740 if (! pfile->state.line_extension)
744 int flag = 0, sysp = 0;
746 flag = read_flag (pfile, flag);
750 flag = read_flag (pfile, flag);
755 flag = read_flag (pfile, flag);
760 flag = read_flag (pfile, flag);
762 sysp = 2, read_flag (pfile, flag);
765 if (reason == FC_ENTER)
767 /* Fake a buffer stack for diagnostics. */
768 cpp_push_buffer (pfile, 0, 0, BUF_FAKE, fname);
769 /* Fake an include for cpp_included. */
770 _cpp_fake_include (pfile, fname);
771 buffer = pfile->buffer;
773 else if (reason == FC_LEAVE)
775 if (buffer->type != BUF_FAKE)
776 cpp_warning (pfile, "file \"%s\" left but not entered",
777 buffer->nominal_fname);
780 cpp_pop_buffer (pfile);
781 buffer = pfile->buffer;
782 if (strcmp (buffer->nominal_fname, fname))
783 cpp_warning (pfile, "expected to return to file \"%s\"",
784 buffer->nominal_fname);
785 if (buffer->lineno + 1 != new_lineno)
786 cpp_warning (pfile, "expected to return to line number %u",
788 if (buffer->sysp != sysp)
789 cpp_warning (pfile, "header flags for \"%s\" have changed",
790 buffer->nominal_fname);
795 buffer->nominal_fname = fname;
797 else if (token.type != CPP_EOF)
799 cpp_error (pfile, "\"%s\" is not a valid filename",
800 cpp_token_as_text (pfile, &token));
804 /* Our line number is incremented after the directive is processed. */
805 buffer->lineno = new_lineno - 1;
806 _cpp_do_file_change (pfile, reason, filename, lineno);
809 /* Arrange the file_change callback. */
811 _cpp_do_file_change (pfile, reason, from_file, from_lineno)
813 enum cpp_fc_reason reason;
814 const char *from_file;
815 unsigned int from_lineno;
817 if (pfile->cb.file_change)
820 cpp_buffer *buffer = pfile->buffer;
823 fc.to.filename = buffer->nominal_fname;
824 fc.to.lineno = buffer->lineno + 1;
825 fc.sysp = buffer->sysp;
826 fc.externc = CPP_OPTION (pfile, cplusplus) && buffer->sysp == 2;
828 /* Caller doesn't need to handle FC_ENTER. */
829 if (reason == FC_ENTER)
833 from_file = buffer->prev->nominal_fname;
834 from_lineno = buffer->prev->lineno;
839 /* Special case for file "foo.i" with "# 1 foo.c" on first line. */
840 else if (reason == FC_RENAME && ! buffer->prev
841 && pfile->directive_pos.line == 1)
844 fc.from.filename = from_file;
845 fc.from.lineno = from_lineno;
846 pfile->cb.file_change (pfile, &fc);
851 * Report a warning or error detected by the program we are
852 * processing. Use the directive's tokens in the error message.
856 do_diagnostic (pfile, code, print_dir)
858 enum error_type code;
861 if (_cpp_begin_message (pfile, code, NULL, 0))
864 fprintf (stderr, "#%s ", pfile->directive->name);
865 pfile->state.prevent_expansion++;
866 cpp_output_line (pfile, stderr);
867 pfile->state.prevent_expansion--;
875 do_diagnostic (pfile, ERROR, 1);
882 do_diagnostic (pfile, WARNING, 1);
885 /* Report program identification. */
893 cpp_get_token (pfile, &str);
894 if (str.type != CPP_STRING)
895 cpp_error (pfile, "invalid #ident");
896 else if (pfile->cb.ident)
897 (*pfile->cb.ident) (pfile, &str.val.str);
902 /* Pragmata handling. We handle some of these, and pass the rest on
903 to the front end. C99 defines three pragmas and says that no macro
904 expansion is to be performed on them; whether or not macro
905 expansion happens for other pragmas is implementation defined.
906 This implementation never macro-expands the text after #pragma. */
908 /* Sub-handlers for the pragmas needing treatment here.
909 They return 1 if the token buffer is to be popped, 0 if not. */
912 struct pragma_entry *next;
917 void (*handler) PARAMS ((cpp_reader *));
918 struct pragma_entry *space;
923 cpp_register_pragma (pfile, space, name, handler)
927 void (*handler) PARAMS ((cpp_reader *));
929 struct pragma_entry **x, *new;
935 struct pragma_entry *p = pfile->pragmas;
936 len = strlen (space);
939 if (p->isnspace && p->len == len && !memcmp (p->name, space, len))
946 cpp_ice (pfile, "unknown #pragma namespace %s", space);
951 new = xnew (struct pragma_entry);
953 new->len = strlen (name);
955 new->u.handler = handler;
962 cpp_register_pragma_space (pfile, space)
966 struct pragma_entry *new;
967 const struct pragma_entry *p = pfile->pragmas;
968 size_t len = strlen (space);
972 if (p->isnspace && p->len == len && !memcmp (p->name, space, len))
973 /* Multiple different callers are allowed to register the same
979 new = xnew (struct pragma_entry);
985 new->next = pfile->pragmas;
986 pfile->pragmas = new;
990 _cpp_init_internal_pragmas (pfile)
994 cpp_register_pragma (pfile, 0, "poison", do_pragma_poison);
995 cpp_register_pragma (pfile, 0, "once", do_pragma_once);
998 cpp_register_pragma_space (pfile, "GCC");
1000 cpp_register_pragma (pfile, "GCC", "poison", do_pragma_poison);
1001 cpp_register_pragma (pfile, "GCC", "system_header", do_pragma_system_header);
1002 cpp_register_pragma (pfile, "GCC", "dependency", do_pragma_dependency);
1009 const struct pragma_entry *p;
1011 const cpp_hashnode *node;
1017 pfile->state.prevent_expansion++;
1018 cpp_start_lookahead (pfile);
1021 cpp_get_token (pfile, &tok);
1022 if (tok.type == CPP_NAME)
1024 node = tok.val.node;
1029 if (strlen (p->name) == len && !memcmp (p->name, name, len))
1038 (*p->u.handler) (pfile);
1047 cpp_stop_lookahead (pfile, drop);
1048 pfile->state.prevent_expansion--;
1050 if (!drop && pfile->cb.def_pragma)
1051 (*pfile->cb.def_pragma) (pfile);
1055 do_pragma_once (pfile)
1058 cpp_warning (pfile, "#pragma once is obsolete");
1060 if (pfile->buffer->prev == NULL)
1061 cpp_warning (pfile, "#pragma once in main file");
1063 _cpp_never_reread (pfile->buffer->inc);
1069 do_pragma_poison (pfile)
1072 /* Poison these symbols so that all subsequent usage produces an
1077 pfile->state.poisoned_ok = 1;
1080 _cpp_lex_token (pfile, &tok);
1081 if (tok.type == CPP_EOF)
1083 if (tok.type != CPP_NAME)
1085 cpp_error (pfile, "invalid #pragma GCC poison directive");
1090 if (hp->flags & NODE_POISONED)
1093 if (hp->type == NT_MACRO)
1094 cpp_warning (pfile, "poisoning existing macro \"%s\"", hp->name);
1095 _cpp_free_definition (hp);
1096 hp->flags |= NODE_POISONED | NODE_DIAGNOSTIC;
1098 pfile->state.poisoned_ok = 0;
1100 #if 0 /* Doesn't quite work yet. */
1101 if (tok.type == CPP_EOF && pfile->cb.poison)
1102 (*pfile->cb.poison) (pfile);
1106 /* Mark the current header as a system header. This will suppress
1107 some categories of warnings (notably those from -pedantic). It is
1108 intended for use in system libraries that cannot be implemented in
1109 conforming C, but cannot be certain that their headers appear in a
1110 system include directory. To prevent abuse, it is rejected in the
1111 primary source file. */
1113 do_pragma_system_header (pfile)
1116 cpp_buffer *buffer = pfile->buffer;
1118 if (buffer->prev == 0)
1119 cpp_warning (pfile, "#pragma system_header ignored outside include file");
1121 cpp_make_system_header (pfile, 1, 0);
1126 /* Check the modified date of the current include file against a specified
1127 file. Issue a diagnostic, if the specified file is newer. We use this to
1128 determine if a fixed header should be refixed. */
1130 do_pragma_dependency (pfile)
1133 cpp_token header, msg;
1136 if (parse_include (pfile, &header))
1139 ordering = _cpp_compare_file_date (pfile, &header);
1141 cpp_warning (pfile, "cannot find source %s",
1142 cpp_token_as_text (pfile, &header));
1143 else if (ordering > 0)
1145 cpp_warning (pfile, "current file is older than %s",
1146 cpp_token_as_text (pfile, &header));
1147 cpp_start_lookahead (pfile);
1148 cpp_get_token (pfile, &msg);
1149 cpp_stop_lookahead (pfile, msg.type == CPP_EOF);
1150 if (msg.type != CPP_EOF)
1151 do_diagnostic (pfile, WARNING, 0);
1155 /* Check syntax is "(string-literal)". Returns 0 on success. */
1157 get__Pragma_string (pfile, string)
1163 cpp_get_token (pfile, &paren);
1164 if (paren.type != CPP_OPEN_PAREN)
1167 cpp_get_token (pfile, string);
1168 if (string->type != CPP_STRING && string->type != CPP_WSTRING)
1171 cpp_get_token (pfile, &paren);
1172 return paren.type != CPP_CLOSE_PAREN;
1175 /* Returns a malloced buffer containing a destringized cpp_string by
1176 removing the first \ of \" and \\ sequences. */
1177 static unsigned char *
1178 destringize (in, len)
1179 const cpp_string *in;
1182 const unsigned char *src, *limit;
1183 unsigned char *dest, *result;
1185 dest = result = (unsigned char *) xmalloc (in->len);
1186 for (src = in->text, limit = src + in->len; src < limit;)
1188 /* We know there is a character following the backslash. */
1189 if (*src == '\\' && (src[1] == '\\' || src[1] == '"'))
1194 *len = dest - result;
1199 _cpp_do__Pragma (pfile)
1203 unsigned char *buffer;
1206 if (get__Pragma_string (pfile, &string))
1208 cpp_error (pfile, "_Pragma takes a parenthesized string literal");
1212 buffer = destringize (&string.val.str, &len);
1213 run_directive (pfile, T_PRAGMA, BUF_PRAGMA, (char *) buffer, len);
1214 free ((PTR) buffer);
1217 /* Just ignore #sccs, on systems where we define it at all. */
1218 #ifdef SCCS_DIRECTIVE
1221 cpp_reader *pfile ATTRIBUTE_UNUSED;
1232 if (! pfile->buffer->was_skipping)
1234 const cpp_hashnode *node = lex_macro_node (pfile);
1237 skip = node->type != NT_MACRO;
1243 push_conditional (pfile, skip, T_IFDEF, 0);
1251 const cpp_hashnode *node = 0;
1253 if (! pfile->buffer->was_skipping)
1255 node = lex_macro_node (pfile);
1257 skip = node->type == NT_MACRO;
1263 push_conditional (pfile, skip, T_IFNDEF, node);
1266 /* #if cooperates with parse_defined to handle multiple-include
1267 optimisations. If macro expansions or identifiers appear in the
1268 expression, we cannot treat it as a controlling conditional, since
1269 their values could change in the future. */
1276 const cpp_hashnode *cmacro = 0;
1278 if (! pfile->buffer->was_skipping)
1280 /* Controlling macro of #if ! defined () */
1281 pfile->mi_ind_cmacro = 0;
1282 skip = _cpp_parse_expr (pfile) == 0;
1283 cmacro = pfile->mi_ind_cmacro;
1286 push_conditional (pfile, skip, T_IF, cmacro);
1289 /* Flip skipping state if appropriate and continue without changing
1290 if_stack; this is so that the error message for missing #endif's
1291 etc. will point to the original #if. */
1297 cpp_buffer *buffer = pfile->buffer;
1298 struct if_stack *ifs = buffer->if_stack;
1301 cpp_error (pfile, "#else without #if");
1304 if (ifs->type == T_ELSE)
1306 cpp_error (pfile, "#else after #else");
1307 cpp_error_with_line (pfile, ifs->pos.line, ifs->pos.col,
1308 "the conditional began here");
1312 /* Buffer->was_skipping is 1 if all conditionals in this chain
1313 have been false, 2 if a conditional has been true. */
1314 if (! ifs->was_skipping && buffer->was_skipping != 2)
1315 buffer->was_skipping = ! buffer->was_skipping;
1317 /* Invalidate any controlling macro. */
1324 /* handle a #elif directive by not changing if_stack either. see the
1325 comment above do_else. */
1331 cpp_buffer *buffer = pfile->buffer;
1332 struct if_stack *ifs = buffer->if_stack;
1335 cpp_error (pfile, "#elif without #if");
1338 if (ifs->type == T_ELSE)
1340 cpp_error (pfile, "#elif after #else");
1341 cpp_error_with_line (pfile, ifs->pos.line, ifs->pos.col,
1342 "the conditional began here");
1346 /* Don't evaluate #elif if our higher level is skipping. */
1347 if (! ifs->was_skipping)
1349 /* Buffer->was_skipping is 1 if all conditionals in this
1350 chain have been false, 2 if a conditional has been true. */
1351 if (buffer->was_skipping == 1)
1352 buffer->was_skipping = ! _cpp_parse_expr (pfile);
1354 buffer->was_skipping = 2;
1356 /* Invalidate any controlling macro. */
1362 /* #endif pops the if stack and resets pfile->skipping. */
1368 cpp_buffer *buffer = pfile->buffer;
1369 struct if_stack *ifs = buffer->if_stack;
1372 cpp_error (pfile, "#endif without #if");
1375 /* If potential control macro, we go back outside again. */
1376 if (ifs->next == 0 && ifs->mi_cmacro)
1378 pfile->mi_state = MI_OUTSIDE;
1379 pfile->mi_cmacro = ifs->mi_cmacro;
1382 buffer->if_stack = ifs->next;
1383 buffer->was_skipping = ifs->was_skipping;
1384 obstack_free (pfile->buffer_ob, ifs);
1390 /* Push an if_stack entry and set pfile->skipping accordingly.
1391 If this is a #ifndef starting at the beginning of a file,
1392 CMACRO is the macro name tested by the #ifndef. */
1395 push_conditional (pfile, skip, type, cmacro)
1399 const cpp_hashnode *cmacro;
1401 struct if_stack *ifs;
1402 cpp_buffer *buffer = pfile->buffer;
1404 ifs = xobnew (pfile->buffer_ob, struct if_stack);
1405 ifs->pos = pfile->directive_pos;
1406 ifs->next = buffer->if_stack;
1407 ifs->was_skipping = buffer->was_skipping;
1409 if (pfile->mi_state == MI_OUTSIDE && pfile->mi_cmacro == 0)
1410 ifs->mi_cmacro = cmacro;
1414 buffer->was_skipping = skip;
1415 buffer->if_stack = ifs;
1418 /* Read the tokens of the answer into the macro pool. Only commit the
1419 memory if we intend it as permanent storage, i.e. the #assert case.
1420 Returns 0 on success. */
1423 parse_answer (pfile, answerp, type)
1425 struct answer **answerp;
1428 cpp_token paren, *token;
1429 struct answer *answer;
1431 if (POOL_FRONT (&pfile->macro_pool) + sizeof (struct answer) >
1432 POOL_LIMIT (&pfile->macro_pool))
1433 _cpp_next_chunk (&pfile->macro_pool, sizeof (struct answer), 0);
1434 answer = (struct answer *) POOL_FRONT (&pfile->macro_pool);
1437 /* In a conditional, it is legal to not have an open paren. We
1438 should save the following token in this case. */
1440 cpp_start_lookahead (pfile);
1441 cpp_get_token (pfile, &paren);
1443 cpp_stop_lookahead (pfile, paren.type == CPP_OPEN_PAREN);
1445 /* If not a paren, see if we're OK. */
1446 if (paren.type != CPP_OPEN_PAREN)
1448 /* In a conditional no answer is a test for any answer. It
1449 could be followed by any token. */
1453 /* #unassert with no answer is valid - it removes all answers. */
1454 if (type == T_UNASSERT && paren.type == CPP_EOF)
1457 cpp_error (pfile, "missing '(' after predicate");
1463 token = &answer->first[answer->count];
1464 /* Check we have room for the token. */
1465 if ((unsigned char *) (token + 1) >= POOL_LIMIT (&pfile->macro_pool))
1467 _cpp_next_chunk (&pfile->macro_pool, sizeof (cpp_token),
1468 (unsigned char **) &answer);
1469 token = &answer->first[answer->count];
1472 cpp_get_token (pfile, token);
1473 if (token->type == CPP_CLOSE_PAREN)
1476 if (token->type == CPP_EOF)
1478 cpp_error (pfile, "missing ')' to complete answer");
1484 if (answer->count == 0)
1486 cpp_error (pfile, "predicate's answer is empty");
1490 /* Drop whitespace at start. */
1491 answer->first->flags &= ~PREV_WHITE;
1494 if (type == T_ASSERT || type == T_UNASSERT)
1499 /* Parses an assertion, returning a pointer to the hash node of the
1500 predicate, or 0 on error. If an answer was supplied, it is placed
1501 in ANSWERP, otherwise it is set to 0. */
1502 static cpp_hashnode *
1503 parse_assertion (pfile, answerp, type)
1505 struct answer **answerp;
1508 cpp_hashnode *result = 0;
1509 cpp_token predicate;
1511 /* We don't expand predicates or answers. */
1512 pfile->state.prevent_expansion++;
1515 cpp_get_token (pfile, &predicate);
1516 if (predicate.type == CPP_EOF)
1517 cpp_error (pfile, "assertion without predicate");
1518 else if (predicate.type != CPP_NAME)
1519 cpp_error (pfile, "predicate must be an identifier");
1520 else if (parse_answer (pfile, answerp, type) == 0)
1522 unsigned int len = predicate.val.node->length;
1523 unsigned char *sym = alloca (len + 1);
1525 /* Prefix '#' to get it out of macro namespace. */
1527 memcpy (sym + 1, predicate.val.node->name, len);
1528 result = cpp_lookup (pfile, sym, len + 1);
1531 pfile->state.prevent_expansion--;
1535 /* Returns a pointer to the pointer to the answer in the answer chain,
1536 or a pointer to NULL if the answer is not in the chain. */
1537 static struct answer **
1538 find_answer (node, candidate)
1540 const struct answer *candidate;
1543 struct answer **result;
1545 for (result = &node->value.answers; *result; result = &(*result)->next)
1547 struct answer *answer = *result;
1549 if (answer->count == candidate->count)
1551 for (i = 0; i < answer->count; i++)
1552 if (! _cpp_equiv_tokens (&answer->first[i], &candidate->first[i]))
1555 if (i == answer->count)
1563 /* Test an assertion within a preprocessor conditional. Returns
1564 non-zero on failure, zero on success. On success, the result of
1565 the test is written into VALUE. */
1567 _cpp_test_assertion (pfile, value)
1571 struct answer *answer;
1574 node = parse_assertion (pfile, &answer, T_IF);
1576 *value = (node->type == NT_ASSERTION &&
1577 (answer == 0 || *find_answer (node, answer) != 0));
1579 /* We don't commit the memory for the answer - it's temporary only. */
1587 struct answer *new_answer;
1590 node = parse_assertion (pfile, &new_answer, T_ASSERT);
1593 /* Place the new answer in the answer list. First check there
1594 is not a duplicate. */
1595 new_answer->next = 0;
1596 if (node->type == NT_ASSERTION)
1598 if (*find_answer (node, new_answer))
1600 cpp_warning (pfile, "\"%s\" re-asserted", node->name + 1);
1603 new_answer->next = node->value.answers;
1605 node->type = NT_ASSERTION;
1606 node->value.answers = new_answer;
1607 POOL_COMMIT (&pfile->macro_pool, (sizeof (struct answer)
1608 + (new_answer->count - 1)
1609 * sizeof (cpp_token)));
1618 struct answer *answer;
1620 node = parse_assertion (pfile, &answer, T_UNASSERT);
1621 /* It isn't an error to #unassert something that isn't asserted. */
1622 if (node && node->type == NT_ASSERTION)
1626 struct answer **p = find_answer (node, answer), *temp;
1628 /* Remove the answer from the list. */
1633 /* Did we free the last answer? */
1634 if (node->value.answers == 0)
1635 node->type = NT_VOID;
1638 _cpp_free_definition (node);
1641 /* We don't commit the memory for the answer - it's temporary only. */
1644 /* These are for -D, -U, -A. */
1646 /* Process the string STR as if it appeared as the body of a #define.
1647 If STR is just an identifier, define it with value 1.
1648 If STR has anything after the identifier, then it should
1649 be identifier=definition. */
1652 cpp_define (pfile, str)
1659 /* Copy the entire option so we can modify it.
1660 Change the first "=" in the string to a space. If there is none,
1661 tack " 1" on the end. */
1663 /* Length including the null. */
1664 count = strlen (str);
1665 buf = (char *) alloca (count + 2);
1666 memcpy (buf, str, count);
1668 p = strchr (str, '=');
1677 run_directive (pfile, T_DEFINE, BUF_CL_OPTION, buf, count);
1680 /* Slight variant of the above for use by initialize_builtins. */
1682 _cpp_define_builtin (pfile, str)
1686 run_directive (pfile, T_DEFINE, BUF_BUILTIN, str, strlen (str));
1689 /* Process MACRO as if it appeared as the body of an #undef. */
1691 cpp_undef (pfile, macro)
1695 run_directive (pfile, T_UNDEF, BUF_CL_OPTION, macro, strlen (macro));
1698 /* Process the string STR as if it appeared as the body of a #assert. */
1700 cpp_assert (pfile, str)
1704 handle_assertion (pfile, str, T_ASSERT);
1707 /* Process STR as if it appeared as the body of an #unassert. */
1709 cpp_unassert (pfile, str)
1713 handle_assertion (pfile, str, T_UNASSERT);
1716 /* Common code for cpp_assert (-A) and cpp_unassert (-A-). */
1718 handle_assertion (pfile, str, type)
1723 size_t count = strlen (str);
1724 const char *p = strchr (str, '=');
1728 /* Copy the entire option so we can modify it. Change the first
1729 "=" in the string to a '(', and tack a ')' on the end. */
1730 char *buf = (char *) alloca (count + 1);
1732 memcpy (buf, str, count);
1738 run_directive (pfile, type, BUF_CL_OPTION, str, count);
1741 /* The number of errors for a given reader. */
1746 return pfile->errors;
1749 /* The options structure. */
1751 cpp_get_options (pfile)
1754 return &pfile->opts;
1757 /* The callbacks structure. */
1759 cpp_get_callbacks (pfile)
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 new->nominal_fname = filename;
1822 new->prev = pfile->buffer;
1824 new->include_stack_listed = 0;
1827 pfile->state.next_bol = 1;
1828 pfile->buffer_stack_depth++;
1829 pfile->buffer = new;
1834 /* If called from do_line, pops a single buffer. Otherwise pops all
1835 buffers until a real file is reached. Generates appropriate
1838 cpp_pop_buffer (pfile)
1842 struct if_stack *ifs;
1846 buffer = pfile->buffer;
1847 /* Walk back up the conditional stack till we reach its level at
1848 entry to this file, issuing error messages. */
1849 for (ifs = buffer->if_stack; ifs; ifs = ifs->next)
1850 cpp_error_with_line (pfile, ifs->pos.line, ifs->pos.col,
1851 "unterminated #%s", dtable[ifs->type].name);
1853 if (buffer->type == BUF_FAKE)
1854 buffer->prev->cur = buffer->cur;
1855 else if (buffer->type == BUF_FILE)
1856 _cpp_pop_file_buffer (pfile, buffer);
1858 pfile->buffer = buffer->prev;
1859 pfile->buffer_stack_depth--;
1861 /* Callbacks only generated for faked or real files. */
1862 if (buffer->type != BUF_FILE && buffer->type != BUF_FAKE)
1865 /* No callback for EOF of last file. */
1869 /* do_line does its own call backs. */
1870 pfile->buffer->include_stack_listed = 0;
1871 if (pfile->directive == &dtable[T_LINE])
1874 _cpp_do_file_change (pfile, FC_LEAVE, buffer->nominal_fname,
1876 if (pfile->buffer->type == BUF_FILE)
1879 cpp_warning (pfile, "file \"%s\" entered but not left",
1880 buffer->nominal_fname);
1883 obstack_free (pfile->buffer_ob, buffer);
1884 return pfile->buffer;
1887 #define obstack_chunk_alloc xmalloc
1888 #define obstack_chunk_free free
1890 _cpp_init_stacks (pfile)
1896 pfile->buffer_ob = xnew (struct obstack);
1897 obstack_init (pfile->buffer_ob);
1899 /* Register the directives. */
1900 for (i = 0; i < (unsigned int) N_DIRECTIVES; i++)
1902 node = cpp_lookup (pfile, dtable[i].name, dtable[i].length);
1903 node->directive_index = i + 1;
1908 _cpp_cleanup_stacks (pfile)
1911 obstack_free (pfile->buffer_ob, 0);
1912 free (pfile->buffer_ob);