* config/i386/mm3dnow.h: New.
[official-gcc.git] / libcpp / directives.c
blob16873dadecf3cd2dbc5b19fda9d4701c00d01d08
1 /* CPP Library. (Directive handling.)
2 Copyright (C) 1986, 1987, 1989, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
3 1999, 2000, 2001, 2002, 2003, 2004 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
11 later version.
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. */
22 #include "config.h"
23 #include "system.h"
24 #include "cpplib.h"
25 #include "internal.h"
26 #include "mkdeps.h"
27 #include "obstack.h"
29 /* Stack of conditionals currently in progress
30 (including both successful and failing conditionals). */
31 struct if_stack
33 struct if_stack *next;
34 unsigned int line; /* Line where condition started. */
35 const cpp_hashnode *mi_cmacro;/* macro name for #ifndef around entire file */
36 bool skip_elses; /* Can future #else / #elif be skipped? */
37 bool was_skipping; /* If were skipping on entry. */
38 int type; /* Most recent conditional for diagnostics. */
41 /* Contains a registered pragma or pragma namespace. */
42 typedef void (*pragma_cb) (cpp_reader *);
43 struct pragma_entry
45 struct pragma_entry *next;
46 const cpp_hashnode *pragma; /* Name and length. */
47 int is_nspace;
48 union {
49 pragma_cb handler;
50 struct pragma_entry *space;
51 } u;
54 /* Values for the origin field of struct directive. KANDR directives
55 come from traditional (K&R) C. STDC89 directives come from the
56 1989 C standard. EXTENSION directives are extensions. */
57 #define KANDR 0
58 #define STDC89 1
59 #define EXTENSION 2
61 /* Values for the flags field of struct directive. COND indicates a
62 conditional; IF_COND an opening conditional. INCL means to treat
63 "..." and <...> as q-char and h-char sequences respectively. IN_I
64 means this directive should be handled even if -fpreprocessed is in
65 effect (these are the directives with callback hooks).
67 EXPAND is set on directives that are always macro-expanded. */
68 #define COND (1 << 0)
69 #define IF_COND (1 << 1)
70 #define INCL (1 << 2)
71 #define IN_I (1 << 3)
72 #define EXPAND (1 << 4)
74 /* Defines one #-directive, including how to handle it. */
75 typedef void (*directive_handler) (cpp_reader *);
76 typedef struct directive directive;
77 struct directive
79 directive_handler handler; /* Function to handle directive. */
80 const uchar *name; /* Name of directive. */
81 unsigned short length; /* Length of name. */
82 unsigned char origin; /* Origin of directive. */
83 unsigned char flags; /* Flags describing this directive. */
86 /* Forward declarations. */
88 static void skip_rest_of_line (cpp_reader *);
89 static void check_eol (cpp_reader *);
90 static void start_directive (cpp_reader *);
91 static void prepare_directive_trad (cpp_reader *);
92 static void end_directive (cpp_reader *, int);
93 static void directive_diagnostics (cpp_reader *, const directive *, int);
94 static void run_directive (cpp_reader *, int, const char *, size_t);
95 static char *glue_header_name (cpp_reader *);
96 static const char *parse_include (cpp_reader *, int *);
97 static void push_conditional (cpp_reader *, int, int, const cpp_hashnode *);
98 static unsigned int read_flag (cpp_reader *, unsigned int);
99 static int strtoul_for_line (const uchar *, unsigned int, unsigned long *);
100 static void do_diagnostic (cpp_reader *, int, int);
101 static cpp_hashnode *lex_macro_node (cpp_reader *);
102 static int undefine_macros (cpp_reader *, cpp_hashnode *, void *);
103 static void do_include_common (cpp_reader *, enum include_type);
104 static struct pragma_entry *lookup_pragma_entry (struct pragma_entry *,
105 const cpp_hashnode *);
106 static struct pragma_entry *insert_pragma_entry (cpp_reader *,
107 struct pragma_entry **,
108 const cpp_hashnode *,
109 pragma_cb);
110 static int count_registered_pragmas (struct pragma_entry *);
111 static char ** save_registered_pragmas (struct pragma_entry *, char **);
112 static char ** restore_registered_pragmas (cpp_reader *, struct pragma_entry *,
113 char **);
114 static void do_pragma_once (cpp_reader *);
115 static void do_pragma_poison (cpp_reader *);
116 static void do_pragma_system_header (cpp_reader *);
117 static void do_pragma_dependency (cpp_reader *);
118 static void do_linemarker (cpp_reader *);
119 static const cpp_token *get_token_no_padding (cpp_reader *);
120 static const cpp_token *get__Pragma_string (cpp_reader *);
121 static void destringize_and_run (cpp_reader *, const cpp_string *);
122 static int parse_answer (cpp_reader *, struct answer **, int);
123 static cpp_hashnode *parse_assertion (cpp_reader *, struct answer **, int);
124 static struct answer ** find_answer (cpp_hashnode *, const struct answer *);
125 static void handle_assertion (cpp_reader *, const char *, int);
127 /* This is the table of directive handlers. It is ordered by
128 frequency of occurrence; the numbers at the end are directive
129 counts from all the source code I have lying around (egcs and libc
130 CVS as of 1999-05-18, plus grub-0.5.91, linux-2.2.9, and
131 pcmcia-cs-3.0.9). This is no longer important as directive lookup
132 is now O(1). All extensions other than #warning and #include_next
133 are deprecated. The name is where the extension appears to have
134 come from. */
136 #define DIRECTIVE_TABLE \
137 D(define, T_DEFINE = 0, KANDR, IN_I) /* 270554 */ \
138 D(include, T_INCLUDE, KANDR, INCL | EXPAND) /* 52262 */ \
139 D(endif, T_ENDIF, KANDR, COND) /* 45855 */ \
140 D(ifdef, T_IFDEF, KANDR, COND | IF_COND) /* 22000 */ \
141 D(if, T_IF, KANDR, COND | IF_COND | EXPAND) /* 18162 */ \
142 D(else, T_ELSE, KANDR, COND) /* 9863 */ \
143 D(ifndef, T_IFNDEF, KANDR, COND | IF_COND) /* 9675 */ \
144 D(undef, T_UNDEF, KANDR, IN_I) /* 4837 */ \
145 D(line, T_LINE, KANDR, EXPAND) /* 2465 */ \
146 D(elif, T_ELIF, STDC89, COND | EXPAND) /* 610 */ \
147 D(error, T_ERROR, STDC89, 0) /* 475 */ \
148 D(pragma, T_PRAGMA, STDC89, IN_I) /* 195 */ \
149 D(warning, T_WARNING, EXTENSION, 0) /* 22 */ \
150 D(include_next, T_INCLUDE_NEXT, EXTENSION, INCL | EXPAND) /* 19 */ \
151 D(ident, T_IDENT, EXTENSION, IN_I) /* 11 */ \
152 D(import, T_IMPORT, EXTENSION, INCL | EXPAND) /* 0 ObjC */ \
153 D(assert, T_ASSERT, EXTENSION, 0) /* 0 SVR4 */ \
154 D(unassert, T_UNASSERT, EXTENSION, 0) /* 0 SVR4 */ \
155 D(sccs, T_SCCS, EXTENSION, 0) /* 0 SVR4? */
157 /* Use the table to generate a series of prototypes, an enum for the
158 directive names, and an array of directive handlers. */
160 #define D(name, t, o, f) static void do_##name (cpp_reader *);
161 DIRECTIVE_TABLE
162 #undef D
164 #define D(n, tag, o, f) tag,
165 enum
167 DIRECTIVE_TABLE
168 N_DIRECTIVES
170 #undef D
172 #define D(name, t, origin, flags) \
173 { do_##name, (const uchar *) #name, \
174 sizeof #name - 1, origin, flags },
175 static const directive dtable[] =
177 DIRECTIVE_TABLE
179 #undef D
180 #undef DIRECTIVE_TABLE
182 /* Wrapper struct directive for linemarkers.
183 The origin is more or less true - the original K+R cpp
184 did use this notation in its preprocessed output. */
185 static const directive linemarker_dir =
187 do_linemarker, U"#", 1, KANDR, IN_I
190 #define SEEN_EOL() (pfile->cur_token[-1].type == CPP_EOF)
192 /* Skip any remaining tokens in a directive. */
193 static void
194 skip_rest_of_line (cpp_reader *pfile)
196 /* Discard all stacked contexts. */
197 while (pfile->context->prev)
198 _cpp_pop_context (pfile);
200 /* Sweep up all tokens remaining on the line. */
201 if (! SEEN_EOL ())
202 while (_cpp_lex_token (pfile)->type != CPP_EOF)
206 /* Ensure there are no stray tokens at the end of a directive. */
207 static void
208 check_eol (cpp_reader *pfile)
210 if (! SEEN_EOL () && _cpp_lex_token (pfile)->type != CPP_EOF)
211 cpp_error (pfile, CPP_DL_PEDWARN, "extra tokens at end of #%s directive",
212 pfile->directive->name);
215 /* Called when entering a directive, _Pragma or command-line directive. */
216 static void
217 start_directive (cpp_reader *pfile)
219 /* Setup in-directive state. */
220 pfile->state.in_directive = 1;
221 pfile->state.save_comments = 0;
223 /* Some handlers need the position of the # for diagnostics. */
224 pfile->directive_line = pfile->line_table->highest_line;
227 /* Called when leaving a directive, _Pragma or command-line directive. */
228 static void
229 end_directive (cpp_reader *pfile, int skip_line)
231 if (CPP_OPTION (pfile, traditional))
233 /* Revert change of prepare_directive_trad. */
234 pfile->state.prevent_expansion--;
236 if (pfile->directive != &dtable[T_DEFINE])
237 _cpp_remove_overlay (pfile);
239 /* We don't skip for an assembler #. */
240 else if (skip_line)
242 skip_rest_of_line (pfile);
243 if (!pfile->keep_tokens)
245 pfile->cur_run = &pfile->base_run;
246 pfile->cur_token = pfile->base_run.base;
250 /* Restore state. */
251 pfile->state.save_comments = ! CPP_OPTION (pfile, discard_comments);
252 pfile->state.in_directive = 0;
253 pfile->state.in_expression = 0;
254 pfile->state.angled_headers = 0;
255 pfile->directive = 0;
258 /* Prepare to handle the directive in pfile->directive. */
259 static void
260 prepare_directive_trad (cpp_reader *pfile)
262 if (pfile->directive != &dtable[T_DEFINE])
264 bool no_expand = (pfile->directive
265 && ! (pfile->directive->flags & EXPAND));
266 bool was_skipping = pfile->state.skipping;
268 pfile->state.in_expression = (pfile->directive == &dtable[T_IF]
269 || pfile->directive == &dtable[T_ELIF]);
270 if (pfile->state.in_expression)
271 pfile->state.skipping = false;
273 if (no_expand)
274 pfile->state.prevent_expansion++;
275 _cpp_scan_out_logical_line (pfile, NULL);
276 if (no_expand)
277 pfile->state.prevent_expansion--;
279 pfile->state.skipping = was_skipping;
280 _cpp_overlay_buffer (pfile, pfile->out.base,
281 pfile->out.cur - pfile->out.base);
284 /* Stop ISO C from expanding anything. */
285 pfile->state.prevent_expansion++;
288 /* Output diagnostics for a directive DIR. INDENTED is nonzero if
289 the '#' was indented. */
290 static void
291 directive_diagnostics (cpp_reader *pfile, const directive *dir, int indented)
293 /* Issue -pedantic warnings for extensions. */
294 if (CPP_PEDANTIC (pfile)
295 && ! pfile->state.skipping
296 && dir->origin == EXTENSION)
297 cpp_error (pfile, CPP_DL_PEDWARN, "#%s is a GCC extension", dir->name);
299 /* Traditionally, a directive is ignored unless its # is in
300 column 1. Therefore in code intended to work with K+R
301 compilers, directives added by C89 must have their #
302 indented, and directives present in traditional C must not.
303 This is true even of directives in skipped conditional
304 blocks. #elif cannot be used at all. */
305 if (CPP_WTRADITIONAL (pfile))
307 if (dir == &dtable[T_ELIF])
308 cpp_error (pfile, CPP_DL_WARNING,
309 "suggest not using #elif in traditional C");
310 else if (indented && dir->origin == KANDR)
311 cpp_error (pfile, CPP_DL_WARNING,
312 "traditional C ignores #%s with the # indented",
313 dir->name);
314 else if (!indented && dir->origin != KANDR)
315 cpp_error (pfile, CPP_DL_WARNING,
316 "suggest hiding #%s from traditional C with an indented #",
317 dir->name);
321 /* Check if we have a known directive. INDENTED is nonzero if the
322 '#' of the directive was indented. This function is in this file
323 to save unnecessarily exporting dtable etc. to cpplex.c. Returns
324 nonzero if the line of tokens has been handled, zero if we should
325 continue processing the line. */
327 _cpp_handle_directive (cpp_reader *pfile, int indented)
329 const directive *dir = 0;
330 const cpp_token *dname;
331 bool was_parsing_args = pfile->state.parsing_args;
332 bool was_discarding_output = pfile->state.discarding_output;
333 int skip = 1;
335 if (was_discarding_output)
336 pfile->state.prevent_expansion = 0;
338 if (was_parsing_args)
340 if (CPP_OPTION (pfile, pedantic))
341 cpp_error (pfile, CPP_DL_PEDWARN,
342 "embedding a directive within macro arguments is not portable");
343 pfile->state.parsing_args = 0;
344 pfile->state.prevent_expansion = 0;
346 start_directive (pfile);
347 dname = _cpp_lex_token (pfile);
349 if (dname->type == CPP_NAME)
351 if (dname->val.node->is_directive)
352 dir = &dtable[dname->val.node->directive_index];
354 /* We do not recognize the # followed by a number extension in
355 assembler code. */
356 else if (dname->type == CPP_NUMBER && CPP_OPTION (pfile, lang) != CLK_ASM)
358 dir = &linemarker_dir;
359 if (CPP_PEDANTIC (pfile) && ! CPP_OPTION (pfile, preprocessed)
360 && ! pfile->state.skipping)
361 cpp_error (pfile, CPP_DL_PEDWARN,
362 "style of line directive is a GCC extension");
365 if (dir)
367 /* If we have a directive that is not an opening conditional,
368 invalidate any control macro. */
369 if (! (dir->flags & IF_COND))
370 pfile->mi_valid = false;
372 /* Kluge alert. In order to be sure that code like this
374 #define HASH #
375 HASH define foo bar
377 does not cause '#define foo bar' to get executed when
378 compiled with -save-temps, we recognize directives in
379 -fpreprocessed mode only if the # is in column 1. cppmacro.c
380 puts a space in front of any '#' at the start of a macro. */
381 if (CPP_OPTION (pfile, preprocessed)
382 && (indented || !(dir->flags & IN_I)))
384 skip = 0;
385 dir = 0;
387 else
389 /* In failed conditional groups, all non-conditional
390 directives are ignored. Before doing that, whether
391 skipping or not, we should lex angle-bracketed headers
392 correctly, and maybe output some diagnostics. */
393 pfile->state.angled_headers = dir->flags & INCL;
394 pfile->state.directive_wants_padding = dir->flags & INCL;
395 if (! CPP_OPTION (pfile, preprocessed))
396 directive_diagnostics (pfile, dir, indented);
397 if (pfile->state.skipping && !(dir->flags & COND))
398 dir = 0;
401 else if (dname->type == CPP_EOF)
402 ; /* CPP_EOF is the "null directive". */
403 else
405 /* An unknown directive. Don't complain about it in assembly
406 source: we don't know where the comments are, and # may
407 introduce assembler pseudo-ops. Don't complain about invalid
408 directives in skipped conditional groups (6.10 p4). */
409 if (CPP_OPTION (pfile, lang) == CLK_ASM)
410 skip = 0;
411 else if (!pfile->state.skipping)
412 cpp_error (pfile, CPP_DL_ERROR, "invalid preprocessing directive #%s",
413 cpp_token_as_text (pfile, dname));
416 pfile->directive = dir;
417 if (CPP_OPTION (pfile, traditional))
418 prepare_directive_trad (pfile);
420 if (dir)
421 pfile->directive->handler (pfile);
422 else if (skip == 0)
423 _cpp_backup_tokens (pfile, 1);
425 end_directive (pfile, skip);
426 if (was_parsing_args)
428 /* Restore state when within macro args. */
429 pfile->state.parsing_args = 2;
430 pfile->state.prevent_expansion = 1;
432 if (was_discarding_output)
433 pfile->state.prevent_expansion = 1;
434 return skip;
437 /* Directive handler wrapper used by the command line option
438 processor. BUF is \n terminated. */
439 static void
440 run_directive (cpp_reader *pfile, int dir_no, const char *buf, size_t count)
442 cpp_push_buffer (pfile, (const uchar *) buf, count,
443 /* from_stage3 */ true);
444 /* Disgusting hack. */
445 if (dir_no == T_PRAGMA)
446 pfile->buffer->file = pfile->buffer->prev->file;
447 start_directive (pfile);
449 /* This is a short-term fix to prevent a leading '#' being
450 interpreted as a directive. */
451 _cpp_clean_line (pfile);
453 pfile->directive = &dtable[dir_no];
454 if (CPP_OPTION (pfile, traditional))
455 prepare_directive_trad (pfile);
456 pfile->directive->handler (pfile);
457 end_directive (pfile, 1);
458 if (dir_no == T_PRAGMA)
459 pfile->buffer->file = NULL;
460 _cpp_pop_buffer (pfile);
463 /* Checks for validity the macro name in #define, #undef, #ifdef and
464 #ifndef directives. */
465 static cpp_hashnode *
466 lex_macro_node (cpp_reader *pfile)
468 const cpp_token *token = _cpp_lex_token (pfile);
470 /* The token immediately after #define must be an identifier. That
471 identifier may not be "defined", per C99 6.10.8p4.
472 In C++, it may not be any of the "named operators" either,
473 per C++98 [lex.digraph], [lex.key].
474 Finally, the identifier may not have been poisoned. (In that case
475 the lexer has issued the error message for us.) */
477 if (token->type == CPP_NAME)
479 cpp_hashnode *node = token->val.node;
481 if (node == pfile->spec_nodes.n_defined)
482 cpp_error (pfile, CPP_DL_ERROR,
483 "\"defined\" cannot be used as a macro name");
484 else if (! (node->flags & NODE_POISONED))
485 return node;
487 else if (token->flags & NAMED_OP)
488 cpp_error (pfile, CPP_DL_ERROR,
489 "\"%s\" cannot be used as a macro name as it is an operator in C++",
490 NODE_NAME (token->val.node));
491 else if (token->type == CPP_EOF)
492 cpp_error (pfile, CPP_DL_ERROR, "no macro name given in #%s directive",
493 pfile->directive->name);
494 else
495 cpp_error (pfile, CPP_DL_ERROR, "macro names must be identifiers");
497 return NULL;
500 /* Process a #define directive. Most work is done in cppmacro.c. */
501 static void
502 do_define (cpp_reader *pfile)
504 cpp_hashnode *node = lex_macro_node (pfile);
506 if (node)
508 /* If we have been requested to expand comments into macros,
509 then re-enable saving of comments. */
510 pfile->state.save_comments =
511 ! CPP_OPTION (pfile, discard_comments_in_macro_exp);
513 if (_cpp_create_definition (pfile, node))
514 if (pfile->cb.define)
515 pfile->cb.define (pfile, pfile->directive_line, node);
519 /* Handle #undef. Mark the identifier NT_VOID in the hash table. */
520 static void
521 do_undef (cpp_reader *pfile)
523 cpp_hashnode *node = lex_macro_node (pfile);
525 if (node)
527 if (pfile->cb.undef)
528 pfile->cb.undef (pfile, pfile->directive_line, node);
530 /* 6.10.3.5 paragraph 2: [#undef] is ignored if the specified
531 identifier is not currently defined as a macro name. */
532 if (node->type == NT_MACRO)
534 if (node->flags & NODE_WARN)
535 cpp_error (pfile, CPP_DL_WARNING,
536 "undefining \"%s\"", NODE_NAME (node));
538 if (CPP_OPTION (pfile, warn_unused_macros))
539 _cpp_warn_if_unused_macro (pfile, node, NULL);
541 _cpp_free_definition (node);
545 check_eol (pfile);
548 /* Undefine a single macro/assertion/whatever. */
550 static int
551 undefine_macros (cpp_reader *pfile ATTRIBUTE_UNUSED, cpp_hashnode *h,
552 void *data_p ATTRIBUTE_UNUSED)
554 /* Body of _cpp_free_definition inlined here for speed.
555 Macros and assertions no longer have anything to free. */
556 h->type = NT_VOID;
557 h->flags &= ~(NODE_POISONED|NODE_BUILTIN|NODE_DISABLED);
558 return 1;
561 /* Undefine all macros and assertions. */
563 void
564 cpp_undef_all (cpp_reader *pfile)
566 cpp_forall_identifiers (pfile, undefine_macros, NULL);
570 /* Helper routine used by parse_include. Reinterpret the current line
571 as an h-char-sequence (< ... >); we are looking at the first token
572 after the <. Returns a malloced filename. */
573 static char *
574 glue_header_name (cpp_reader *pfile)
576 const cpp_token *token;
577 char *buffer;
578 size_t len, total_len = 0, capacity = 1024;
580 /* To avoid lexed tokens overwriting our glued name, we can only
581 allocate from the string pool once we've lexed everything. */
582 buffer = xmalloc (capacity);
583 for (;;)
585 token = get_token_no_padding (pfile);
587 if (token->type == CPP_GREATER)
588 break;
589 if (token->type == CPP_EOF)
591 cpp_error (pfile, CPP_DL_ERROR, "missing terminating > character");
592 break;
595 len = cpp_token_len (token) + 2; /* Leading space, terminating \0. */
596 if (total_len + len > capacity)
598 capacity = (capacity + len) * 2;
599 buffer = xrealloc (buffer, capacity);
602 if (token->flags & PREV_WHITE)
603 buffer[total_len++] = ' ';
605 total_len = (cpp_spell_token (pfile, token, (uchar *) &buffer[total_len])
606 - (uchar *) buffer);
609 buffer[total_len] = '\0';
610 return buffer;
613 /* Returns the file name of #include, #include_next, #import and
614 #pragma dependency. The string is malloced and the caller should
615 free it. Returns NULL on error. */
616 static const char *
617 parse_include (cpp_reader *pfile, int *pangle_brackets)
619 char *fname;
620 const cpp_token *header;
622 /* Allow macro expansion. */
623 header = get_token_no_padding (pfile);
624 if (header->type == CPP_STRING || header->type == CPP_HEADER_NAME)
626 fname = xmalloc (header->val.str.len - 1);
627 memcpy (fname, header->val.str.text + 1, header->val.str.len - 2);
628 fname[header->val.str.len - 2] = '\0';
629 *pangle_brackets = header->type == CPP_HEADER_NAME;
631 else if (header->type == CPP_LESS)
633 fname = glue_header_name (pfile);
634 *pangle_brackets = 1;
636 else
638 const unsigned char *dir;
640 if (pfile->directive == &dtable[T_PRAGMA])
641 dir = U"pragma dependency";
642 else
643 dir = pfile->directive->name;
644 cpp_error (pfile, CPP_DL_ERROR, "#%s expects \"FILENAME\" or <FILENAME>",
645 dir);
647 return NULL;
650 check_eol (pfile);
651 return fname;
654 /* Handle #include, #include_next and #import. */
655 static void
656 do_include_common (cpp_reader *pfile, enum include_type type)
658 const char *fname;
659 int angle_brackets;
661 fname = parse_include (pfile, &angle_brackets);
662 if (!fname)
663 return;
665 /* Prevent #include recursion. */
666 if (pfile->line_table->depth >= CPP_STACK_MAX)
667 cpp_error (pfile, CPP_DL_ERROR, "#include nested too deeply");
668 else
670 /* Get out of macro context, if we are. */
671 skip_rest_of_line (pfile);
673 if (pfile->cb.include)
674 pfile->cb.include (pfile, pfile->directive_line,
675 pfile->directive->name, fname, angle_brackets);
677 _cpp_stack_include (pfile, fname, angle_brackets, type);
680 free ((void *) fname);
683 static void
684 do_include (cpp_reader *pfile)
686 do_include_common (pfile, IT_INCLUDE);
689 static void
690 do_import (cpp_reader *pfile)
692 do_include_common (pfile, IT_IMPORT);
695 static void
696 do_include_next (cpp_reader *pfile)
698 enum include_type type = IT_INCLUDE_NEXT;
700 /* If this is the primary source file, warn and use the normal
701 search logic. */
702 if (! pfile->buffer->prev)
704 cpp_error (pfile, CPP_DL_WARNING,
705 "#include_next in primary source file");
706 type = IT_INCLUDE;
708 do_include_common (pfile, type);
711 /* Subroutine of do_linemarker. Read possible flags after file name.
712 LAST is the last flag seen; 0 if this is the first flag. Return the
713 flag if it is valid, 0 at the end of the directive. Otherwise
714 complain. */
715 static unsigned int
716 read_flag (cpp_reader *pfile, unsigned int last)
718 const cpp_token *token = _cpp_lex_token (pfile);
720 if (token->type == CPP_NUMBER && token->val.str.len == 1)
722 unsigned int flag = token->val.str.text[0] - '0';
724 if (flag > last && flag <= 4
725 && (flag != 4 || last == 3)
726 && (flag != 2 || last == 0))
727 return flag;
730 if (token->type != CPP_EOF)
731 cpp_error (pfile, CPP_DL_ERROR, "invalid flag \"%s\" in line directive",
732 cpp_token_as_text (pfile, token));
733 return 0;
736 /* Subroutine of do_line and do_linemarker. Convert a number in STR,
737 of length LEN, to binary; store it in NUMP, and return 0 if the
738 number was well-formed, 1 if not. Temporary, hopefully. */
739 static int
740 strtoul_for_line (const uchar *str, unsigned int len, long unsigned int *nump)
742 unsigned long reg = 0;
743 uchar c;
744 while (len--)
746 c = *str++;
747 if (!ISDIGIT (c))
748 return 1;
749 reg *= 10;
750 reg += c - '0';
752 *nump = reg;
753 return 0;
756 /* Interpret #line command.
757 Note that the filename string (if any) is a true string constant
758 (escapes are interpreted), unlike in #line. */
759 static void
760 do_line (cpp_reader *pfile)
762 const struct line_maps *line_table = pfile->line_table;
763 const struct line_map *map = &line_table->maps[line_table->used - 1];
764 const cpp_token *token;
765 const char *new_file = map->to_file;
766 unsigned long new_lineno;
768 /* C99 raised the minimum limit on #line numbers. */
769 unsigned int cap = CPP_OPTION (pfile, c99) ? 2147483647 : 32767;
771 /* #line commands expand macros. */
772 token = cpp_get_token (pfile);
773 if (token->type != CPP_NUMBER
774 || strtoul_for_line (token->val.str.text, token->val.str.len,
775 &new_lineno))
777 cpp_error (pfile, CPP_DL_ERROR,
778 "\"%s\" after #line is not a positive integer",
779 cpp_token_as_text (pfile, token));
780 return;
783 if (CPP_PEDANTIC (pfile) && (new_lineno == 0 || new_lineno > cap))
784 cpp_error (pfile, CPP_DL_PEDWARN, "line number out of range");
786 token = cpp_get_token (pfile);
787 if (token->type == CPP_STRING)
789 cpp_string s = { 0, 0 };
790 if (cpp_interpret_string_notranslate (pfile, &token->val.str, 1,
791 &s, false))
792 new_file = (const char *)s.text;
793 check_eol (pfile);
795 else if (token->type != CPP_EOF)
797 cpp_error (pfile, CPP_DL_ERROR, "\"%s\" is not a valid filename",
798 cpp_token_as_text (pfile, token));
799 return;
802 skip_rest_of_line (pfile);
803 _cpp_do_file_change (pfile, LC_RENAME, new_file, new_lineno,
804 map->sysp);
807 /* Interpret the # 44 "file" [flags] notation, which has slightly
808 different syntax and semantics from #line: Flags are allowed,
809 and we never complain about the line number being too big. */
810 static void
811 do_linemarker (cpp_reader *pfile)
813 const struct line_maps *line_table = pfile->line_table;
814 const struct line_map *map = &line_table->maps[line_table->used - 1];
815 const cpp_token *token;
816 const char *new_file = map->to_file;
817 unsigned long new_lineno;
818 unsigned int new_sysp = map->sysp;
819 enum lc_reason reason = LC_RENAME;
820 int flag;
822 /* Back up so we can get the number again. Putting this in
823 _cpp_handle_directive risks two calls to _cpp_backup_tokens in
824 some circumstances, which can segfault. */
825 _cpp_backup_tokens (pfile, 1);
827 /* #line commands expand macros. */
828 token = cpp_get_token (pfile);
829 if (token->type != CPP_NUMBER
830 || strtoul_for_line (token->val.str.text, token->val.str.len,
831 &new_lineno))
833 cpp_error (pfile, CPP_DL_ERROR,
834 "\"%s\" after # is not a positive integer",
835 cpp_token_as_text (pfile, token));
836 return;
839 token = cpp_get_token (pfile);
840 if (token->type == CPP_STRING)
842 cpp_string s = { 0, 0 };
843 if (cpp_interpret_string_notranslate (pfile, &token->val.str,
844 1, &s, false))
845 new_file = (const char *)s.text;
847 new_sysp = 0;
848 flag = read_flag (pfile, 0);
849 if (flag == 1)
851 reason = LC_ENTER;
852 /* Fake an include for cpp_included (). */
853 _cpp_fake_include (pfile, new_file);
854 flag = read_flag (pfile, flag);
856 else if (flag == 2)
858 reason = LC_LEAVE;
859 flag = read_flag (pfile, flag);
861 if (flag == 3)
863 new_sysp = 1;
864 flag = read_flag (pfile, flag);
865 if (flag == 4)
866 new_sysp = 2;
867 pfile->buffer->sysp = new_sysp;
870 check_eol (pfile);
872 else if (token->type != CPP_EOF)
874 cpp_error (pfile, CPP_DL_ERROR, "\"%s\" is not a valid filename",
875 cpp_token_as_text (pfile, token));
876 return;
879 skip_rest_of_line (pfile);
880 _cpp_do_file_change (pfile, reason, new_file, new_lineno, new_sysp);
883 /* Arrange the file_change callback. pfile->line has changed to
884 FILE_LINE of TO_FILE, for reason REASON. SYSP is 1 for a system
885 header, 2 for a system header that needs to be extern "C" protected,
886 and zero otherwise. */
887 void
888 _cpp_do_file_change (cpp_reader *pfile, enum lc_reason reason,
889 const char *to_file, unsigned int file_line,
890 unsigned int sysp)
892 const struct line_map *map = linemap_add (pfile->line_table, reason, sysp,
893 to_file, file_line);
894 if (map != NULL)
895 linemap_line_start (pfile->line_table, map->to_line, 127);
897 if (pfile->cb.file_change)
898 pfile->cb.file_change (pfile, map);
901 /* Report a warning or error detected by the program we are
902 processing. Use the directive's tokens in the error message. */
903 static void
904 do_diagnostic (cpp_reader *pfile, int code, int print_dir)
906 if (_cpp_begin_message (pfile, code, pfile->cur_token[-1].src_loc, 0))
908 if (print_dir)
909 fprintf (stderr, "#%s ", pfile->directive->name);
910 pfile->state.prevent_expansion++;
911 cpp_output_line (pfile, stderr);
912 pfile->state.prevent_expansion--;
916 static void
917 do_error (cpp_reader *pfile)
919 do_diagnostic (pfile, CPP_DL_ERROR, 1);
922 static void
923 do_warning (cpp_reader *pfile)
925 /* We want #warning diagnostics to be emitted in system headers too. */
926 do_diagnostic (pfile, CPP_DL_WARNING_SYSHDR, 1);
929 /* Report program identification. */
930 static void
931 do_ident (cpp_reader *pfile)
933 const cpp_token *str = cpp_get_token (pfile);
935 if (str->type != CPP_STRING)
936 cpp_error (pfile, CPP_DL_ERROR, "invalid #ident directive");
937 else if (pfile->cb.ident)
938 pfile->cb.ident (pfile, pfile->directive_line, &str->val.str);
940 check_eol (pfile);
943 /* Lookup a PRAGMA name in a singly-linked CHAIN. Returns the
944 matching entry, or NULL if none is found. The returned entry could
945 be the start of a namespace chain, or a pragma. */
946 static struct pragma_entry *
947 lookup_pragma_entry (struct pragma_entry *chain, const cpp_hashnode *pragma)
949 while (chain && chain->pragma != pragma)
950 chain = chain->next;
952 return chain;
955 /* Create and insert a pragma entry for NAME at the beginning of a
956 singly-linked CHAIN. If handler is NULL, it is a namespace,
957 otherwise it is a pragma and its handler. */
958 static struct pragma_entry *
959 insert_pragma_entry (cpp_reader *pfile, struct pragma_entry **chain,
960 const cpp_hashnode *pragma, pragma_cb handler)
962 struct pragma_entry *new;
964 new = (struct pragma_entry *)
965 _cpp_aligned_alloc (pfile, sizeof (struct pragma_entry));
966 new->pragma = pragma;
967 if (handler)
969 new->is_nspace = 0;
970 new->u.handler = handler;
972 else
974 new->is_nspace = 1;
975 new->u.space = NULL;
978 new->next = *chain;
979 *chain = new;
980 return new;
983 /* Register a pragma NAME in namespace SPACE. If SPACE is null, it
984 goes in the global namespace. HANDLER is the handler it will call,
985 which must be non-NULL. */
986 void
987 cpp_register_pragma (cpp_reader *pfile, const char *space, const char *name,
988 pragma_cb handler)
990 struct pragma_entry **chain = &pfile->pragmas;
991 struct pragma_entry *entry;
992 const cpp_hashnode *node;
994 if (!handler)
995 abort ();
997 if (space)
999 node = cpp_lookup (pfile, U space, strlen (space));
1000 entry = lookup_pragma_entry (*chain, node);
1001 if (!entry)
1002 entry = insert_pragma_entry (pfile, chain, node, NULL);
1003 else if (!entry->is_nspace)
1004 goto clash;
1005 chain = &entry->u.space;
1008 /* Check for duplicates. */
1009 node = cpp_lookup (pfile, U name, strlen (name));
1010 entry = lookup_pragma_entry (*chain, node);
1011 if (entry)
1013 if (entry->is_nspace)
1014 clash:
1015 cpp_error (pfile, CPP_DL_ICE,
1016 "registering \"%s\" as both a pragma and a pragma namespace",
1017 NODE_NAME (node));
1018 else if (space)
1019 cpp_error (pfile, CPP_DL_ICE, "#pragma %s %s is already registered",
1020 space, name);
1021 else
1022 cpp_error (pfile, CPP_DL_ICE, "#pragma %s is already registered", name);
1024 else
1025 insert_pragma_entry (pfile, chain, node, handler);
1028 /* Register the pragmas the preprocessor itself handles. */
1029 void
1030 _cpp_init_internal_pragmas (cpp_reader *pfile)
1032 /* Pragmas in the global namespace. */
1033 cpp_register_pragma (pfile, 0, "once", do_pragma_once);
1035 /* New GCC-specific pragmas should be put in the GCC namespace. */
1036 cpp_register_pragma (pfile, "GCC", "poison", do_pragma_poison);
1037 cpp_register_pragma (pfile, "GCC", "system_header", do_pragma_system_header);
1038 cpp_register_pragma (pfile, "GCC", "dependency", do_pragma_dependency);
1041 /* Return the number of registered pragmas in PE. */
1043 static int
1044 count_registered_pragmas (struct pragma_entry *pe)
1046 int ct = 0;
1047 for (; pe != NULL; pe = pe->next)
1049 if (pe->is_nspace)
1050 ct += count_registered_pragmas (pe->u.space);
1051 ct++;
1053 return ct;
1056 /* Save into SD the names of the registered pragmas referenced by PE,
1057 and return a pointer to the next free space in SD. */
1059 static char **
1060 save_registered_pragmas (struct pragma_entry *pe, char **sd)
1062 for (; pe != NULL; pe = pe->next)
1064 if (pe->is_nspace)
1065 sd = save_registered_pragmas (pe->u.space, sd);
1066 *sd++ = xmemdup (HT_STR (&pe->pragma->ident),
1067 HT_LEN (&pe->pragma->ident),
1068 HT_LEN (&pe->pragma->ident) + 1);
1070 return sd;
1073 /* Return a newly-allocated array which saves the names of the
1074 registered pragmas. */
1076 char **
1077 _cpp_save_pragma_names (cpp_reader *pfile)
1079 int ct = count_registered_pragmas (pfile->pragmas);
1080 char **result = xnewvec (char *, ct);
1081 (void) save_registered_pragmas (pfile->pragmas, result);
1082 return result;
1085 /* Restore from SD the names of the registered pragmas referenced by PE,
1086 and return a pointer to the next unused name in SD. */
1088 static char **
1089 restore_registered_pragmas (cpp_reader *pfile, struct pragma_entry *pe,
1090 char **sd)
1092 for (; pe != NULL; pe = pe->next)
1094 if (pe->is_nspace)
1095 sd = restore_registered_pragmas (pfile, pe->u.space, sd);
1096 pe->pragma = cpp_lookup (pfile, U *sd, strlen (*sd));
1097 free (*sd);
1098 sd++;
1100 return sd;
1103 /* Restore the names of the registered pragmas from SAVED. */
1105 void
1106 _cpp_restore_pragma_names (cpp_reader *pfile, char **saved)
1108 (void) restore_registered_pragmas (pfile, pfile->pragmas, saved);
1109 free (saved);
1112 /* Pragmata handling. We handle some, and pass the rest on to the
1113 front end. C99 defines three pragmas and says that no macro
1114 expansion is to be performed on them; whether or not macro
1115 expansion happens for other pragmas is implementation defined.
1116 This implementation never macro-expands the text after #pragma. */
1117 static void
1118 do_pragma (cpp_reader *pfile)
1120 const struct pragma_entry *p = NULL;
1121 const cpp_token *token, *pragma_token = pfile->cur_token;
1122 unsigned int count = 1;
1124 pfile->state.prevent_expansion++;
1126 token = cpp_get_token (pfile);
1127 if (token->type == CPP_NAME)
1129 p = lookup_pragma_entry (pfile->pragmas, token->val.node);
1130 if (p && p->is_nspace)
1132 count = 2;
1133 token = cpp_get_token (pfile);
1134 if (token->type == CPP_NAME)
1135 p = lookup_pragma_entry (p->u.space, token->val.node);
1136 else
1137 p = NULL;
1141 if (p)
1143 /* Since the handler below doesn't get the line number, that it
1144 might need for diagnostics, make sure it has the right
1145 numbers in place. */
1146 if (pfile->cb.line_change)
1147 (*pfile->cb.line_change) (pfile, pragma_token, false);
1148 (*p->u.handler) (pfile);
1150 else if (pfile->cb.def_pragma)
1152 _cpp_backup_tokens (pfile, count);
1153 pfile->cb.def_pragma (pfile, pfile->directive_line);
1156 pfile->state.prevent_expansion--;
1159 /* Handle #pragma once. */
1160 static void
1161 do_pragma_once (cpp_reader *pfile)
1163 if (pfile->buffer->prev == NULL)
1164 cpp_error (pfile, CPP_DL_WARNING, "#pragma once in main file");
1166 check_eol (pfile);
1167 _cpp_mark_file_once_only (pfile, pfile->buffer->file);
1170 /* Handle #pragma GCC poison, to poison one or more identifiers so
1171 that the lexer produces a hard error for each subsequent usage. */
1172 static void
1173 do_pragma_poison (cpp_reader *pfile)
1175 const cpp_token *tok;
1176 cpp_hashnode *hp;
1178 pfile->state.poisoned_ok = 1;
1179 for (;;)
1181 tok = _cpp_lex_token (pfile);
1182 if (tok->type == CPP_EOF)
1183 break;
1184 if (tok->type != CPP_NAME)
1186 cpp_error (pfile, CPP_DL_ERROR,
1187 "invalid #pragma GCC poison directive");
1188 break;
1191 hp = tok->val.node;
1192 if (hp->flags & NODE_POISONED)
1193 continue;
1195 if (hp->type == NT_MACRO)
1196 cpp_error (pfile, CPP_DL_WARNING, "poisoning existing macro \"%s\"",
1197 NODE_NAME (hp));
1198 _cpp_free_definition (hp);
1199 hp->flags |= NODE_POISONED | NODE_DIAGNOSTIC;
1201 pfile->state.poisoned_ok = 0;
1204 /* Mark the current header as a system header. This will suppress
1205 some categories of warnings (notably those from -pedantic). It is
1206 intended for use in system libraries that cannot be implemented in
1207 conforming C, but cannot be certain that their headers appear in a
1208 system include directory. To prevent abuse, it is rejected in the
1209 primary source file. */
1210 static void
1211 do_pragma_system_header (cpp_reader *pfile)
1213 cpp_buffer *buffer = pfile->buffer;
1215 if (buffer->prev == 0)
1216 cpp_error (pfile, CPP_DL_WARNING,
1217 "#pragma system_header ignored outside include file");
1218 else
1220 check_eol (pfile);
1221 skip_rest_of_line (pfile);
1222 cpp_make_system_header (pfile, 1, 0);
1226 /* Check the modified date of the current include file against a specified
1227 file. Issue a diagnostic, if the specified file is newer. We use this to
1228 determine if a fixed header should be refixed. */
1229 static void
1230 do_pragma_dependency (cpp_reader *pfile)
1232 const char *fname;
1233 int angle_brackets, ordering;
1235 fname = parse_include (pfile, &angle_brackets);
1236 if (!fname)
1237 return;
1239 ordering = _cpp_compare_file_date (pfile, fname, angle_brackets);
1240 if (ordering < 0)
1241 cpp_error (pfile, CPP_DL_WARNING, "cannot find source file %s", fname);
1242 else if (ordering > 0)
1244 cpp_error (pfile, CPP_DL_WARNING,
1245 "current file is older than %s", fname);
1246 if (cpp_get_token (pfile)->type != CPP_EOF)
1248 _cpp_backup_tokens (pfile, 1);
1249 do_diagnostic (pfile, CPP_DL_WARNING, 0);
1253 free ((void *) fname);
1256 /* Get a token but skip padding. */
1257 static const cpp_token *
1258 get_token_no_padding (cpp_reader *pfile)
1260 for (;;)
1262 const cpp_token *result = cpp_get_token (pfile);
1263 if (result->type != CPP_PADDING)
1264 return result;
1268 /* Check syntax is "(string-literal)". Returns the string on success,
1269 or NULL on failure. */
1270 static const cpp_token *
1271 get__Pragma_string (cpp_reader *pfile)
1273 const cpp_token *string;
1275 if (get_token_no_padding (pfile)->type != CPP_OPEN_PAREN)
1276 return NULL;
1278 string = get_token_no_padding (pfile);
1279 if (string->type != CPP_STRING && string->type != CPP_WSTRING)
1280 return NULL;
1282 if (get_token_no_padding (pfile)->type != CPP_CLOSE_PAREN)
1283 return NULL;
1285 return string;
1288 /* Destringize IN into a temporary buffer, by removing the first \ of
1289 \" and \\ sequences, and process the result as a #pragma directive. */
1290 static void
1291 destringize_and_run (cpp_reader *pfile, const cpp_string *in)
1293 const unsigned char *src, *limit;
1294 char *dest, *result;
1296 dest = result = alloca (in->len - 1);
1297 src = in->text + 1 + (in->text[0] == 'L');
1298 limit = in->text + in->len - 1;
1299 while (src < limit)
1301 /* We know there is a character following the backslash. */
1302 if (*src == '\\' && (src[1] == '\\' || src[1] == '"'))
1303 src++;
1304 *dest++ = *src++;
1306 *dest = '\n';
1308 /* Ugh; an awful kludge. We are really not set up to be lexing
1309 tokens when in the middle of a macro expansion. Use a new
1310 context to force cpp_get_token to lex, and so skip_rest_of_line
1311 doesn't go beyond the end of the text. Also, remember the
1312 current lexing position so we can return to it later.
1314 Something like line-at-a-time lexing should remove the need for
1315 this. */
1317 cpp_context *saved_context = pfile->context;
1318 cpp_token *saved_cur_token = pfile->cur_token;
1319 tokenrun *saved_cur_run = pfile->cur_run;
1321 pfile->context = xnew (cpp_context);
1322 pfile->context->macro = 0;
1323 pfile->context->prev = 0;
1324 run_directive (pfile, T_PRAGMA, result, dest - result);
1325 free (pfile->context);
1326 pfile->context = saved_context;
1327 pfile->cur_token = saved_cur_token;
1328 pfile->cur_run = saved_cur_run;
1331 /* See above comment. For the moment, we'd like
1333 token1 _Pragma ("foo") token2
1335 to be output as
1337 token1
1338 # 7 "file.c"
1339 #pragma foo
1340 # 7 "file.c"
1341 token2
1343 Getting the line markers is a little tricky. */
1344 if (pfile->cb.line_change)
1345 pfile->cb.line_change (pfile, pfile->cur_token, false);
1348 /* Handle the _Pragma operator. */
1349 void
1350 _cpp_do__Pragma (cpp_reader *pfile)
1352 const cpp_token *string = get__Pragma_string (pfile);
1354 if (string)
1355 destringize_and_run (pfile, &string->val.str);
1356 else
1357 cpp_error (pfile, CPP_DL_ERROR,
1358 "_Pragma takes a parenthesized string literal");
1361 /* Ignore #sccs on all systems. */
1362 static void
1363 do_sccs (cpp_reader *pfile ATTRIBUTE_UNUSED)
1367 /* Handle #ifdef. */
1368 static void
1369 do_ifdef (cpp_reader *pfile)
1371 int skip = 1;
1373 if (! pfile->state.skipping)
1375 const cpp_hashnode *node = lex_macro_node (pfile);
1377 if (node)
1379 skip = node->type != NT_MACRO;
1380 _cpp_mark_macro_used (node);
1381 check_eol (pfile);
1385 push_conditional (pfile, skip, T_IFDEF, 0);
1388 /* Handle #ifndef. */
1389 static void
1390 do_ifndef (cpp_reader *pfile)
1392 int skip = 1;
1393 const cpp_hashnode *node = 0;
1395 if (! pfile->state.skipping)
1397 node = lex_macro_node (pfile);
1399 if (node)
1401 skip = node->type == NT_MACRO;
1402 _cpp_mark_macro_used (node);
1403 check_eol (pfile);
1407 push_conditional (pfile, skip, T_IFNDEF, node);
1410 /* _cpp_parse_expr puts a macro in a "#if !defined ()" expression in
1411 pfile->mi_ind_cmacro so we can handle multiple-include
1412 optimizations. If macro expansion occurs in the expression, we
1413 cannot treat it as a controlling conditional, since the expansion
1414 could change in the future. That is handled by cpp_get_token. */
1415 static void
1416 do_if (cpp_reader *pfile)
1418 int skip = 1;
1420 if (! pfile->state.skipping)
1421 skip = _cpp_parse_expr (pfile) == false;
1423 push_conditional (pfile, skip, T_IF, pfile->mi_ind_cmacro);
1426 /* Flip skipping state if appropriate and continue without changing
1427 if_stack; this is so that the error message for missing #endif's
1428 etc. will point to the original #if. */
1429 static void
1430 do_else (cpp_reader *pfile)
1432 cpp_buffer *buffer = pfile->buffer;
1433 struct if_stack *ifs = buffer->if_stack;
1435 if (ifs == NULL)
1436 cpp_error (pfile, CPP_DL_ERROR, "#else without #if");
1437 else
1439 if (ifs->type == T_ELSE)
1441 cpp_error (pfile, CPP_DL_ERROR, "#else after #else");
1442 cpp_error_with_line (pfile, CPP_DL_ERROR, ifs->line, 0,
1443 "the conditional began here");
1445 ifs->type = T_ELSE;
1447 /* Skip any future (erroneous) #elses or #elifs. */
1448 pfile->state.skipping = ifs->skip_elses;
1449 ifs->skip_elses = true;
1451 /* Invalidate any controlling macro. */
1452 ifs->mi_cmacro = 0;
1454 /* Only check EOL if was not originally skipping. */
1455 if (!ifs->was_skipping && CPP_OPTION (pfile, warn_endif_labels))
1456 check_eol (pfile);
1460 /* Handle a #elif directive by not changing if_stack either. See the
1461 comment above do_else. */
1462 static void
1463 do_elif (cpp_reader *pfile)
1465 cpp_buffer *buffer = pfile->buffer;
1466 struct if_stack *ifs = buffer->if_stack;
1468 if (ifs == NULL)
1469 cpp_error (pfile, CPP_DL_ERROR, "#elif without #if");
1470 else
1472 if (ifs->type == T_ELSE)
1474 cpp_error (pfile, CPP_DL_ERROR, "#elif after #else");
1475 cpp_error_with_line (pfile, CPP_DL_ERROR, ifs->line, 0,
1476 "the conditional began here");
1478 ifs->type = T_ELIF;
1480 /* Only evaluate this if we aren't skipping elses. During
1481 evaluation, set skipping to false to get lexer warnings. */
1482 if (ifs->skip_elses)
1483 pfile->state.skipping = 1;
1484 else
1486 pfile->state.skipping = 0;
1487 pfile->state.skipping = ! _cpp_parse_expr (pfile);
1488 ifs->skip_elses = ! pfile->state.skipping;
1491 /* Invalidate any controlling macro. */
1492 ifs->mi_cmacro = 0;
1496 /* #endif pops the if stack and resets pfile->state.skipping. */
1497 static void
1498 do_endif (cpp_reader *pfile)
1500 cpp_buffer *buffer = pfile->buffer;
1501 struct if_stack *ifs = buffer->if_stack;
1503 if (ifs == NULL)
1504 cpp_error (pfile, CPP_DL_ERROR, "#endif without #if");
1505 else
1507 /* Only check EOL if was not originally skipping. */
1508 if (!ifs->was_skipping && CPP_OPTION (pfile, warn_endif_labels))
1509 check_eol (pfile);
1511 /* If potential control macro, we go back outside again. */
1512 if (ifs->next == 0 && ifs->mi_cmacro)
1514 pfile->mi_valid = true;
1515 pfile->mi_cmacro = ifs->mi_cmacro;
1518 buffer->if_stack = ifs->next;
1519 pfile->state.skipping = ifs->was_skipping;
1520 obstack_free (&pfile->buffer_ob, ifs);
1524 /* Push an if_stack entry for a preprocessor conditional, and set
1525 pfile->state.skipping to SKIP. If TYPE indicates the conditional
1526 is #if or #ifndef, CMACRO is a potentially controlling macro, and
1527 we need to check here that we are at the top of the file. */
1528 static void
1529 push_conditional (cpp_reader *pfile, int skip, int type,
1530 const cpp_hashnode *cmacro)
1532 struct if_stack *ifs;
1533 cpp_buffer *buffer = pfile->buffer;
1535 ifs = xobnew (&pfile->buffer_ob, struct if_stack);
1536 ifs->line = pfile->directive_line;
1537 ifs->next = buffer->if_stack;
1538 ifs->skip_elses = pfile->state.skipping || !skip;
1539 ifs->was_skipping = pfile->state.skipping;
1540 ifs->type = type;
1541 /* This condition is effectively a test for top-of-file. */
1542 if (pfile->mi_valid && pfile->mi_cmacro == 0)
1543 ifs->mi_cmacro = cmacro;
1544 else
1545 ifs->mi_cmacro = 0;
1547 pfile->state.skipping = skip;
1548 buffer->if_stack = ifs;
1551 /* Read the tokens of the answer into the macro pool, in a directive
1552 of type TYPE. Only commit the memory if we intend it as permanent
1553 storage, i.e. the #assert case. Returns 0 on success, and sets
1554 ANSWERP to point to the answer. */
1555 static int
1556 parse_answer (cpp_reader *pfile, struct answer **answerp, int type)
1558 const cpp_token *paren;
1559 struct answer *answer;
1560 unsigned int acount;
1562 /* In a conditional, it is legal to not have an open paren. We
1563 should save the following token in this case. */
1564 paren = cpp_get_token (pfile);
1566 /* If not a paren, see if we're OK. */
1567 if (paren->type != CPP_OPEN_PAREN)
1569 /* In a conditional no answer is a test for any answer. It
1570 could be followed by any token. */
1571 if (type == T_IF)
1573 _cpp_backup_tokens (pfile, 1);
1574 return 0;
1577 /* #unassert with no answer is valid - it removes all answers. */
1578 if (type == T_UNASSERT && paren->type == CPP_EOF)
1579 return 0;
1581 cpp_error (pfile, CPP_DL_ERROR, "missing '(' after predicate");
1582 return 1;
1585 for (acount = 0;; acount++)
1587 size_t room_needed;
1588 const cpp_token *token = cpp_get_token (pfile);
1589 cpp_token *dest;
1591 if (token->type == CPP_CLOSE_PAREN)
1592 break;
1594 if (token->type == CPP_EOF)
1596 cpp_error (pfile, CPP_DL_ERROR, "missing ')' to complete answer");
1597 return 1;
1600 /* struct answer includes the space for one token. */
1601 room_needed = (sizeof (struct answer) + acount * sizeof (cpp_token));
1603 if (BUFF_ROOM (pfile->a_buff) < room_needed)
1604 _cpp_extend_buff (pfile, &pfile->a_buff, sizeof (struct answer));
1606 dest = &((struct answer *) BUFF_FRONT (pfile->a_buff))->first[acount];
1607 *dest = *token;
1609 /* Drop whitespace at start, for answer equivalence purposes. */
1610 if (acount == 0)
1611 dest->flags &= ~PREV_WHITE;
1614 if (acount == 0)
1616 cpp_error (pfile, CPP_DL_ERROR, "predicate's answer is empty");
1617 return 1;
1620 answer = (struct answer *) BUFF_FRONT (pfile->a_buff);
1621 answer->count = acount;
1622 answer->next = NULL;
1623 *answerp = answer;
1625 return 0;
1628 /* Parses an assertion directive of type TYPE, returning a pointer to
1629 the hash node of the predicate, or 0 on error. If an answer was
1630 supplied, it is placed in ANSWERP, otherwise it is set to 0. */
1631 static cpp_hashnode *
1632 parse_assertion (cpp_reader *pfile, struct answer **answerp, int type)
1634 cpp_hashnode *result = 0;
1635 const cpp_token *predicate;
1637 /* We don't expand predicates or answers. */
1638 pfile->state.prevent_expansion++;
1640 *answerp = 0;
1641 predicate = cpp_get_token (pfile);
1642 if (predicate->type == CPP_EOF)
1643 cpp_error (pfile, CPP_DL_ERROR, "assertion without predicate");
1644 else if (predicate->type != CPP_NAME)
1645 cpp_error (pfile, CPP_DL_ERROR, "predicate must be an identifier");
1646 else if (parse_answer (pfile, answerp, type) == 0)
1648 unsigned int len = NODE_LEN (predicate->val.node);
1649 unsigned char *sym = alloca (len + 1);
1651 /* Prefix '#' to get it out of macro namespace. */
1652 sym[0] = '#';
1653 memcpy (sym + 1, NODE_NAME (predicate->val.node), len);
1654 result = cpp_lookup (pfile, sym, len + 1);
1657 pfile->state.prevent_expansion--;
1658 return result;
1661 /* Returns a pointer to the pointer to CANDIDATE in the answer chain,
1662 or a pointer to NULL if the answer is not in the chain. */
1663 static struct answer **
1664 find_answer (cpp_hashnode *node, const struct answer *candidate)
1666 unsigned int i;
1667 struct answer **result;
1669 for (result = &node->value.answers; *result; result = &(*result)->next)
1671 struct answer *answer = *result;
1673 if (answer->count == candidate->count)
1675 for (i = 0; i < answer->count; i++)
1676 if (! _cpp_equiv_tokens (&answer->first[i], &candidate->first[i]))
1677 break;
1679 if (i == answer->count)
1680 break;
1684 return result;
1687 /* Test an assertion within a preprocessor conditional. Returns
1688 nonzero on failure, zero on success. On success, the result of
1689 the test is written into VALUE, otherwise the value 0. */
1691 _cpp_test_assertion (cpp_reader *pfile, unsigned int *value)
1693 struct answer *answer;
1694 cpp_hashnode *node;
1696 node = parse_assertion (pfile, &answer, T_IF);
1698 /* For recovery, an erroneous assertion expression is handled as a
1699 failing assertion. */
1700 *value = 0;
1702 if (node)
1703 *value = (node->type == NT_ASSERTION &&
1704 (answer == 0 || *find_answer (node, answer) != 0));
1705 else if (pfile->cur_token[-1].type == CPP_EOF)
1706 _cpp_backup_tokens (pfile, 1);
1708 /* We don't commit the memory for the answer - it's temporary only. */
1709 return node == 0;
1712 /* Handle #assert. */
1713 static void
1714 do_assert (cpp_reader *pfile)
1716 struct answer *new_answer;
1717 cpp_hashnode *node;
1719 node = parse_assertion (pfile, &new_answer, T_ASSERT);
1720 if (node)
1722 size_t answer_size;
1724 /* Place the new answer in the answer list. First check there
1725 is not a duplicate. */
1726 new_answer->next = 0;
1727 if (node->type == NT_ASSERTION)
1729 if (*find_answer (node, new_answer))
1731 cpp_error (pfile, CPP_DL_WARNING, "\"%s\" re-asserted",
1732 NODE_NAME (node) + 1);
1733 return;
1735 new_answer->next = node->value.answers;
1738 answer_size = sizeof (struct answer) + ((new_answer->count - 1)
1739 * sizeof (cpp_token));
1740 /* Commit or allocate storage for the object. */
1741 if (pfile->hash_table->alloc_subobject)
1743 struct answer *temp_answer = new_answer;
1744 new_answer = pfile->hash_table->alloc_subobject (answer_size);
1745 memcpy (new_answer, temp_answer, answer_size);
1747 else
1748 BUFF_FRONT (pfile->a_buff) += answer_size;
1750 node->type = NT_ASSERTION;
1751 node->value.answers = new_answer;
1752 check_eol (pfile);
1756 /* Handle #unassert. */
1757 static void
1758 do_unassert (cpp_reader *pfile)
1760 cpp_hashnode *node;
1761 struct answer *answer;
1763 node = parse_assertion (pfile, &answer, T_UNASSERT);
1764 /* It isn't an error to #unassert something that isn't asserted. */
1765 if (node && node->type == NT_ASSERTION)
1767 if (answer)
1769 struct answer **p = find_answer (node, answer), *temp;
1771 /* Remove the answer from the list. */
1772 temp = *p;
1773 if (temp)
1774 *p = temp->next;
1776 /* Did we free the last answer? */
1777 if (node->value.answers == 0)
1778 node->type = NT_VOID;
1780 check_eol (pfile);
1782 else
1783 _cpp_free_definition (node);
1786 /* We don't commit the memory for the answer - it's temporary only. */
1789 /* These are for -D, -U, -A. */
1791 /* Process the string STR as if it appeared as the body of a #define.
1792 If STR is just an identifier, define it with value 1.
1793 If STR has anything after the identifier, then it should
1794 be identifier=definition. */
1795 void
1796 cpp_define (cpp_reader *pfile, const char *str)
1798 char *buf, *p;
1799 size_t count;
1801 /* Copy the entire option so we can modify it.
1802 Change the first "=" in the string to a space. If there is none,
1803 tack " 1" on the end. */
1805 count = strlen (str);
1806 buf = alloca (count + 3);
1807 memcpy (buf, str, count);
1809 p = strchr (str, '=');
1810 if (p)
1811 buf[p - str] = ' ';
1812 else
1814 buf[count++] = ' ';
1815 buf[count++] = '1';
1817 buf[count] = '\n';
1819 run_directive (pfile, T_DEFINE, buf, count);
1822 /* Slight variant of the above for use by initialize_builtins. */
1823 void
1824 _cpp_define_builtin (cpp_reader *pfile, const char *str)
1826 size_t len = strlen (str);
1827 char *buf = alloca (len + 1);
1828 memcpy (buf, str, len);
1829 buf[len] = '\n';
1830 run_directive (pfile, T_DEFINE, buf, len);
1833 /* Process MACRO as if it appeared as the body of an #undef. */
1834 void
1835 cpp_undef (cpp_reader *pfile, const char *macro)
1837 size_t len = strlen (macro);
1838 char *buf = alloca (len + 1);
1839 memcpy (buf, macro, len);
1840 buf[len] = '\n';
1841 run_directive (pfile, T_UNDEF, buf, len);
1844 /* Process the string STR as if it appeared as the body of a #assert. */
1845 void
1846 cpp_assert (cpp_reader *pfile, const char *str)
1848 handle_assertion (pfile, str, T_ASSERT);
1851 /* Process STR as if it appeared as the body of an #unassert. */
1852 void
1853 cpp_unassert (cpp_reader *pfile, const char *str)
1855 handle_assertion (pfile, str, T_UNASSERT);
1858 /* Common code for cpp_assert (-A) and cpp_unassert (-A-). */
1859 static void
1860 handle_assertion (cpp_reader *pfile, const char *str, int type)
1862 size_t count = strlen (str);
1863 const char *p = strchr (str, '=');
1865 /* Copy the entire option so we can modify it. Change the first
1866 "=" in the string to a '(', and tack a ')' on the end. */
1867 char *buf = alloca (count + 2);
1869 memcpy (buf, str, count);
1870 if (p)
1872 buf[p - str] = '(';
1873 buf[count++] = ')';
1875 buf[count] = '\n';
1876 str = buf;
1878 run_directive (pfile, type, str, count);
1881 /* The number of errors for a given reader. */
1882 unsigned int
1883 cpp_errors (cpp_reader *pfile)
1885 return pfile->errors;
1888 /* The options structure. */
1889 cpp_options *
1890 cpp_get_options (cpp_reader *pfile)
1892 return &pfile->opts;
1895 /* The callbacks structure. */
1896 cpp_callbacks *
1897 cpp_get_callbacks (cpp_reader *pfile)
1899 return &pfile->cb;
1902 /* Copy the given callbacks structure to our own. */
1903 void
1904 cpp_set_callbacks (cpp_reader *pfile, cpp_callbacks *cb)
1906 pfile->cb = *cb;
1909 /* The dependencies structure. (Creates one if it hasn't already been.) */
1910 struct deps *
1911 cpp_get_deps (cpp_reader *pfile)
1913 if (!pfile->deps)
1914 pfile->deps = deps_init ();
1915 return pfile->deps;
1918 /* Push a new buffer on the buffer stack. Returns the new buffer; it
1919 doesn't fail. It does not generate a file change call back; that
1920 is the responsibility of the caller. */
1921 cpp_buffer *
1922 cpp_push_buffer (cpp_reader *pfile, const uchar *buffer, size_t len,
1923 int from_stage3)
1925 cpp_buffer *new = xobnew (&pfile->buffer_ob, cpp_buffer);
1927 /* Clears, amongst other things, if_stack and mi_cmacro. */
1928 memset (new, 0, sizeof (cpp_buffer));
1930 new->next_line = new->buf = buffer;
1931 new->rlimit = buffer + len;
1932 new->from_stage3 = from_stage3;
1933 new->prev = pfile->buffer;
1934 new->need_line = true;
1936 pfile->buffer = new;
1938 return new;
1941 /* Pops a single buffer, with a file change call-back if appropriate.
1942 Then pushes the next -include file, if any remain. */
1943 void
1944 _cpp_pop_buffer (cpp_reader *pfile)
1946 cpp_buffer *buffer = pfile->buffer;
1947 struct _cpp_file *inc = buffer->file;
1948 struct if_stack *ifs;
1950 /* Walk back up the conditional stack till we reach its level at
1951 entry to this file, issuing error messages. */
1952 for (ifs = buffer->if_stack; ifs; ifs = ifs->next)
1953 cpp_error_with_line (pfile, CPP_DL_ERROR, ifs->line, 0,
1954 "unterminated #%s", dtable[ifs->type].name);
1956 /* In case of a missing #endif. */
1957 pfile->state.skipping = 0;
1959 /* _cpp_do_file_change expects pfile->buffer to be the new one. */
1960 pfile->buffer = buffer->prev;
1962 free (buffer->notes);
1964 /* Free the buffer object now; we may want to push a new buffer
1965 in _cpp_push_next_include_file. */
1966 obstack_free (&pfile->buffer_ob, buffer);
1968 if (inc)
1970 _cpp_pop_file_buffer (pfile, inc);
1972 _cpp_do_file_change (pfile, LC_LEAVE, 0, 0, 0);
1976 /* Enter all recognized directives in the hash table. */
1977 void
1978 _cpp_init_directives (cpp_reader *pfile)
1980 unsigned int i;
1981 cpp_hashnode *node;
1983 for (i = 0; i < (unsigned int) N_DIRECTIVES; i++)
1985 node = cpp_lookup (pfile, dtable[i].name, dtable[i].length);
1986 node->is_directive = 1;
1987 node->directive_index = i;