1 /* Definitions for CPP library.
2    Copyright (C) 1995-2013 Free Software Foundation, Inc.
3    Written by Per Bothner, 1994-95.
4 
5 This program is free software; you can redistribute it and/or modify it
6 under the terms of the GNU General Public License as published by the
7 Free Software Foundation; either version 3, or (at your option) any
8 later version.
9 
10 This program is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13 GNU General Public License for more details.
14 
15 You should have received a copy of the GNU General Public License
16 along with this program; see the file COPYING3.  If not see
17 <http://www.gnu.org/licenses/>.
18 
19  In other words, you are welcome to use, share and improve this program.
20  You are forbidden to forbid anyone else to use, share and improve
21  what you give them.   Help stamp out software-hoarding!  */
22 #ifndef LIBCPP_CPPLIB_H
23 #define LIBCPP_CPPLIB_H
24 
25 #include <sys/types.h>
26 #include "symtab.h"
27 #include "line-map.h"
28 
29 typedef struct cpp_reader cpp_reader;
30 typedef struct cpp_buffer cpp_buffer;
31 typedef struct cpp_options cpp_options;
32 typedef struct cpp_token cpp_token;
33 typedef struct cpp_string cpp_string;
34 typedef struct cpp_hashnode cpp_hashnode;
35 typedef struct cpp_macro cpp_macro;
36 typedef struct cpp_callbacks cpp_callbacks;
37 typedef struct cpp_dir cpp_dir;
38 
39 struct answer;
40 struct _cpp_file;
41 
42 /* The first three groups, apart from '=', can appear in preprocessor
43    expressions (+= and -= are used to indicate unary + and - resp.).
44    This allows a lookup table to be implemented in _cpp_parse_expr.
45 
46    The first group, to CPP_LAST_EQ, can be immediately followed by an
47    '='.  The lexer needs operators ending in '=', like ">>=", to be in
48    the same order as their counterparts without the '=', like ">>".
49 
50    See the cpp_operator table optab in expr.c if you change the order or
51    add or remove anything in the first group.  */
52 
53 #define TTYPE_TABLE							\
54   OP(EQ,		"=")						\
55   OP(NOT,		"!")						\
56   OP(GREATER,		">")	/* compare */				\
57   OP(LESS,		"<")						\
58   OP(PLUS,		"+")	/* math */				\
59   OP(MINUS,		"-")						\
60   OP(MULT,		"*")						\
61   OP(DIV,		"/")						\
62   OP(MOD,		"%")						\
63   OP(AND,		"&")	/* bit ops */				\
64   OP(OR,		"|")						\
65   OP(XOR,		"^")						\
66   OP(RSHIFT,		">>")						\
67   OP(LSHIFT,		"<<")						\
68 									\
69   OP(COMPL,		"~")						\
70   OP(AND_AND,		"&&")	/* logical */				\
71   OP(OR_OR,		"||")						\
72   OP(QUERY,		"?")						\
73   OP(COLON,		":")						\
74   OP(COMMA,		",")	/* grouping */				\
75   OP(OPEN_PAREN,	"(")						\
76   OP(CLOSE_PAREN,	")")						\
77   TK(EOF,		NONE)						\
78   OP(EQ_EQ,		"==")	/* compare */				\
79   OP(NOT_EQ,		"!=")						\
80   OP(GREATER_EQ,	">=")						\
81   OP(LESS_EQ,		"<=")						\
82 									\
83   /* These two are unary + / - in preprocessor expressions.  */		\
84   OP(PLUS_EQ,		"+=")	/* math */				\
85   OP(MINUS_EQ,		"-=")						\
86 									\
87   OP(MULT_EQ,		"*=")						\
88   OP(DIV_EQ,		"/=")						\
89   OP(MOD_EQ,		"%=")						\
90   OP(AND_EQ,		"&=")	/* bit ops */				\
91   OP(OR_EQ,		"|=")						\
92   OP(XOR_EQ,		"^=")						\
93   OP(RSHIFT_EQ,		">>=")						\
94   OP(LSHIFT_EQ,		"<<=")						\
95   /* Digraphs together, beginning with CPP_FIRST_DIGRAPH.  */		\
96   OP(HASH,		"#")	/* digraphs */				\
97   OP(PASTE,		"##")						\
98   OP(OPEN_SQUARE,	"[")						\
99   OP(CLOSE_SQUARE,	"]")						\
100   OP(OPEN_BRACE,	"{")						\
101   OP(CLOSE_BRACE,	"}")						\
102   /* The remainder of the punctuation.	Order is not significant.  */	\
103   OP(SEMICOLON,		";")	/* structure */				\
104   OP(ELLIPSIS,		"...")						\
105   OP(PLUS_PLUS,		"++")	/* increment */				\
106   OP(MINUS_MINUS,	"--")						\
107   OP(DEREF,		"->")	/* accessors */				\
108   OP(DOT,		".")						\
109   OP(SCOPE,		"::")						\
110   OP(DEREF_STAR,	"->*")						\
111   OP(DOT_STAR,		".*")						\
112   OP(ATSIGN,		"@")  /* used in Objective-C */			\
113 									\
114   TK(NAME,		IDENT)	 /* word */				\
115   TK(AT_NAME,		IDENT)	 /* @word - Objective-C */		\
116   TK(NUMBER,		LITERAL) /* 34_be+ta  */			\
117 									\
118   TK(CHAR,		LITERAL) /* 'char' */				\
119   TK(WCHAR,		LITERAL) /* L'char' */				\
120   TK(CHAR16,		LITERAL) /* u'char' */				\
121   TK(CHAR32,		LITERAL) /* U'char' */				\
122   TK(OTHER,		LITERAL) /* stray punctuation */		\
123 									\
124   TK(STRING,		LITERAL) /* "string" */				\
125   TK(WSTRING,		LITERAL) /* L"string" */			\
126   TK(STRING16,		LITERAL) /* u"string" */			\
127   TK(STRING32,		LITERAL) /* U"string" */			\
128   TK(UTF8STRING,	LITERAL) /* u8"string" */			\
129   TK(OBJC_STRING,	LITERAL) /* @"string" - Objective-C */		\
130   TK(HEADER_NAME,	LITERAL) /* <stdio.h> in #include */		\
131 									\
132   TK(CHAR_USERDEF,	LITERAL) /* 'char'_suffix - C++-0x */		\
133   TK(WCHAR_USERDEF,	LITERAL) /* L'char'_suffix - C++-0x */		\
134   TK(CHAR16_USERDEF,	LITERAL) /* u'char'_suffix - C++-0x */		\
135   TK(CHAR32_USERDEF,	LITERAL) /* U'char'_suffix - C++-0x */		\
136   TK(STRING_USERDEF,	LITERAL) /* "string"_suffix - C++-0x */		\
137   TK(WSTRING_USERDEF,	LITERAL) /* L"string"_suffix - C++-0x */	\
138   TK(STRING16_USERDEF,	LITERAL) /* u"string"_suffix - C++-0x */	\
139   TK(STRING32_USERDEF,	LITERAL) /* U"string"_suffix - C++-0x */	\
140   TK(UTF8STRING_USERDEF,LITERAL) /* u8"string"_suffix - C++-0x */	\
141 									\
142   TK(COMMENT,		LITERAL) /* Only if output comments.  */	\
143 				 /* SPELL_LITERAL happens to DTRT.  */	\
144   TK(MACRO_ARG,		NONE)	 /* Macro argument.  */			\
145   TK(PRAGMA,		NONE)	 /* Only for deferred pragmas.  */	\
146   TK(PRAGMA_EOL,	NONE)	 /* End-of-line for deferred pragmas.  */ \
147   TK(PADDING,		NONE)	 /* Whitespace for -E.	*/
148 
149 #define OP(e, s) CPP_ ## e,
150 #define TK(e, s) CPP_ ## e,
151 enum cpp_ttype
152 {
153   TTYPE_TABLE
154   N_TTYPES,
155 
156   /* Positions in the table.  */
157   CPP_LAST_EQ        = CPP_LSHIFT,
158   CPP_FIRST_DIGRAPH  = CPP_HASH,
159   CPP_LAST_PUNCTUATOR= CPP_ATSIGN,
160   CPP_LAST_CPP_OP    = CPP_LESS_EQ
161 };
162 #undef OP
163 #undef TK
164 
165 /* C language kind, used when calling cpp_create_reader.  */
166 enum c_lang {CLK_GNUC89 = 0, CLK_GNUC99, CLK_GNUC11,
167 	     CLK_STDC89, CLK_STDC94, CLK_STDC99, CLK_STDC11,
168 	     CLK_GNUCXX, CLK_CXX98, CLK_GNUCXX11, CLK_CXX11, CLK_ASM};
169 
170 /* Payload of a NUMBER, STRING, CHAR or COMMENT token.  */
171 struct GTY(()) cpp_string {
172   unsigned int len;
173   const unsigned char *text;
174 };
175 
176 /* Flags for the cpp_token structure.  */
177 #define PREV_WHITE	(1 << 0) /* If whitespace before this token.  */
178 #define DIGRAPH		(1 << 1) /* If it was a digraph.  */
179 #define STRINGIFY_ARG	(1 << 2) /* If macro argument to be stringified.  */
180 #define PASTE_LEFT	(1 << 3) /* If on LHS of a ## operator.  */
181 #define NAMED_OP	(1 << 4) /* C++ named operators.  */
182 #define NO_EXPAND	(1 << 5) /* Do not macro-expand this token.  */
183 #define BOL		(1 << 6) /* Token at beginning of line.  */
184 #define PURE_ZERO	(1 << 7) /* Single 0 digit, used by the C++ frontend,
185 				    set in c-lex.c.  */
186 #define SP_DIGRAPH	(1 << 8) /* # or ## token was a digraph.  */
187 #define SP_PREV_WHITE	(1 << 9) /* If whitespace before a ##
188 				    operator, or before this token
189 				    after a # operator.  */
190 
191 /* Specify which field, if any, of the cpp_token union is used.  */
192 
193 enum cpp_token_fld_kind {
194   CPP_TOKEN_FLD_NODE,
195   CPP_TOKEN_FLD_SOURCE,
196   CPP_TOKEN_FLD_STR,
197   CPP_TOKEN_FLD_ARG_NO,
198   CPP_TOKEN_FLD_TOKEN_NO,
199   CPP_TOKEN_FLD_PRAGMA,
200   CPP_TOKEN_FLD_NONE
201 };
202 
203 /* A macro argument in the cpp_token union.  */
204 struct GTY(()) cpp_macro_arg {
205   /* Argument number.  */
206   unsigned int arg_no;
207 };
208 
209 /* An identifier in the cpp_token union.  */
210 struct GTY(()) cpp_identifier {
211   /* The canonical (UTF-8) spelling of the identifier.  */
212   cpp_hashnode *
213     GTY ((nested_ptr (union tree_node,
214 		"%h ? CPP_HASHNODE (GCC_IDENT_TO_HT_IDENT (%h)) : NULL",
215 			"%h ? HT_IDENT_TO_GCC_IDENT (HT_NODE (%h)) : NULL")))
216        node;
217 };
218 
219 /* A preprocessing token.  This has been carefully packed and should
220    occupy 16 bytes on 32-bit hosts and 24 bytes on 64-bit hosts.  */
221 struct GTY(()) cpp_token {
222   source_location src_loc;	/* Location of first char of token.  */
223   ENUM_BITFIELD(cpp_ttype) type : CHAR_BIT;  /* token type */
224   unsigned short flags;		/* flags - see above */
225 
226   union cpp_token_u
227   {
228     /* An identifier.  */
229     struct cpp_identifier GTY ((tag ("CPP_TOKEN_FLD_NODE"))) node;
230 
231     /* Inherit padding from this token.  */
232     cpp_token * GTY ((tag ("CPP_TOKEN_FLD_SOURCE"))) source;
233 
234     /* A string, or number.  */
235     struct cpp_string GTY ((tag ("CPP_TOKEN_FLD_STR"))) str;
236 
237     /* Argument no. for a CPP_MACRO_ARG.  */
238     struct cpp_macro_arg GTY ((tag ("CPP_TOKEN_FLD_ARG_NO"))) macro_arg;
239 
240     /* Original token no. for a CPP_PASTE (from a sequence of
241        consecutive paste tokens in a macro expansion).  */
242     unsigned int GTY ((tag ("CPP_TOKEN_FLD_TOKEN_NO"))) token_no;
243 
244     /* Caller-supplied identifier for a CPP_PRAGMA.  */
245     unsigned int GTY ((tag ("CPP_TOKEN_FLD_PRAGMA"))) pragma;
246   } GTY ((desc ("cpp_token_val_index (&%1)"))) val;
247 };
248 
249 /* Say which field is in use.  */
250 extern enum cpp_token_fld_kind cpp_token_val_index (cpp_token *tok);
251 
252 /* A type wide enough to hold any multibyte source character.
253    cpplib's character constant interpreter requires an unsigned type.
254    Also, a typedef for the signed equivalent.
255    The width of this type is capped at 32 bits; there do exist targets
256    where wchar_t is 64 bits, but only in a non-default mode, and there
257    would be no meaningful interpretation for a wchar_t value greater
258    than 2^32 anyway -- the widest wide-character encoding around is
259    ISO 10646, which stops at 2^31.  */
260 #if CHAR_BIT * SIZEOF_INT >= 32
261 # define CPPCHAR_SIGNED_T int
262 #elif CHAR_BIT * SIZEOF_LONG >= 32
263 # define CPPCHAR_SIGNED_T long
264 #else
265 # error "Cannot find a least-32-bit signed integer type"
266 #endif
267 typedef unsigned CPPCHAR_SIGNED_T cppchar_t;
268 typedef CPPCHAR_SIGNED_T cppchar_signed_t;
269 
270 /* Style of header dependencies to generate.  */
271 enum cpp_deps_style { DEPS_NONE = 0, DEPS_USER, DEPS_SYSTEM };
272 
273 /* The possible normalization levels, from most restrictive to least.  */
274 enum cpp_normalize_level {
275   /* In NFKC.  */
276   normalized_KC = 0,
277   /* In NFC.  */
278   normalized_C,
279   /* In NFC, except for subsequences where being in NFC would make
280      the identifier invalid.  */
281   normalized_identifier_C,
282   /* Not normalized at all.  */
283   normalized_none
284 };
285 
286 /* This structure is nested inside struct cpp_reader, and
287    carries all the options visible to the command line.  */
288 struct cpp_options
289 {
290   /* Characters between tab stops.  */
291   unsigned int tabstop;
292 
293   /* The language we're preprocessing.  */
294   enum c_lang lang;
295 
296   /* Nonzero means use extra default include directories for C++.  */
297   unsigned char cplusplus;
298 
299   /* Nonzero means handle cplusplus style comments.  */
300   unsigned char cplusplus_comments;
301 
302   /* Nonzero means define __OBJC__, treat @ as a special token, use
303      the OBJC[PLUS]_INCLUDE_PATH environment variable, and allow
304      "#import".  */
305   unsigned char objc;
306 
307   /* Nonzero means don't copy comments into the output file.  */
308   unsigned char discard_comments;
309 
310   /* Nonzero means don't copy comments into the output file during
311      macro expansion.  */
312   unsigned char discard_comments_in_macro_exp;
313 
314   /* Nonzero means process the ISO trigraph sequences.  */
315   unsigned char trigraphs;
316 
317   /* Nonzero means process the ISO digraph sequences.  */
318   unsigned char digraphs;
319 
320   /* Nonzero means to allow hexadecimal floats and LL suffixes.  */
321   unsigned char extended_numbers;
322 
323   /* Nonzero means process u/U prefix literals (UTF-16/32).  */
324   unsigned char uliterals;
325 
326   /* Nonzero means process r/R raw strings.  If this is set, uliterals
327      must be set as well.  */
328   unsigned char rliterals;
329 
330   /* Nonzero means print names of header files (-H).  */
331   unsigned char print_include_names;
332 
333   /* Nonzero means complain about deprecated features.  */
334   unsigned char cpp_warn_deprecated;
335 
336   /* Nonzero means warn if slash-star appears in a comment.  */
337   unsigned char warn_comments;
338 
339   /* Nonzero means warn if a user-supplied include directory does not
340      exist.  */
341   unsigned char warn_missing_include_dirs;
342 
343   /* Nonzero means warn if there are any trigraphs.  */
344   unsigned char warn_trigraphs;
345 
346   /* Nonzero means warn about multicharacter charconsts.  */
347   unsigned char warn_multichar;
348 
349   /* Nonzero means warn about various incompatibilities with
350      traditional C.  */
351   unsigned char cpp_warn_traditional;
352 
353   /* Nonzero means warn about long long numeric constants.  */
354   unsigned char cpp_warn_long_long;
355 
356   /* Nonzero means warn about text after an #endif (or #else).  */
357   unsigned char warn_endif_labels;
358 
359   /* Nonzero means warn about implicit sign changes owing to integer
360      promotions.  */
361   unsigned char warn_num_sign_change;
362 
363   /* Zero means don't warn about __VA_ARGS__ usage in c89 pedantic mode.
364      Presumably the usage is protected by the appropriate #ifdef.  */
365   unsigned char warn_variadic_macros;
366 
367   /* Nonzero means warn about builtin macros that are redefined or
368      explicitly undefined.  */
369   unsigned char warn_builtin_macro_redefined;
370 
371   /* Nonzero means we should look for header.gcc files that remap file
372      names.  */
373   unsigned char remap;
374 
375   /* Zero means dollar signs are punctuation.  */
376   unsigned char dollars_in_ident;
377 
378   /* Nonzero means UCNs are accepted in identifiers.  */
379   unsigned char extended_identifiers;
380 
381   /* True if we should warn about dollars in identifiers or numbers
382      for this translation unit.  */
383   unsigned char warn_dollars;
384 
385   /* Nonzero means warn if undefined identifiers are evaluated in an #if.  */
386   unsigned char warn_undef;
387 
388   /* Nonzero means warn of unused macros from the main file.  */
389   unsigned char warn_unused_macros;
390 
391   /* Nonzero for the 1999 C Standard, including corrigenda and amendments.  */
392   unsigned char c99;
393 
394   /* Nonzero if we are conforming to a specific C or C++ standard.  */
395   unsigned char std;
396 
397   /* Nonzero means give all the error messages the ANSI standard requires.  */
398   unsigned char cpp_pedantic;
399 
400   /* Nonzero means we're looking at already preprocessed code, so don't
401      bother trying to do macro expansion and whatnot.  */
402   unsigned char preprocessed;
403 
404   /* Nonzero means we are going to emit debugging logs during
405      preprocessing.  */
406   unsigned char debug;
407 
408   /* Nonzero means we are tracking locations of tokens involved in
409      macro expansion. 1 Means we track the location in degraded mode
410      where we do not track locations of tokens resulting from the
411      expansion of arguments of function-like macro.  2 Means we do
412      track all macro expansions. This last option is the one that
413      consumes the highest amount of memory.  */
414   unsigned char track_macro_expansion;
415 
416   /* Nonzero means handle C++ alternate operator names.  */
417   unsigned char operator_names;
418 
419   /* Nonzero means warn about use of C++ alternate operator names.  */
420   unsigned char warn_cxx_operator_names;
421 
422   /* True for traditional preprocessing.  */
423   unsigned char traditional;
424 
425   /* Nonzero for C++ 2011 Standard user-defnied literals.  */
426   unsigned char user_literals;
427 
428   /* Nonzero means warn when a string or character literal is followed by a
429      ud-suffix which does not beging with an underscore.  */
430   unsigned char warn_literal_suffix;
431 
432   /* Nonzero means interpret imaginary, fixed-point, or other gnu extension
433      literal number suffixes as user-defined literal number suffixes.  */
434   unsigned char ext_numeric_literals;
435 
436   /* Holds the name of the target (execution) character set.  */
437   const char *narrow_charset;
438 
439   /* Holds the name of the target wide character set.  */
440   const char *wide_charset;
441 
442   /* Holds the name of the input character set.  */
443   const char *input_charset;
444 
445   /* The minimum permitted level of normalization before a warning
446      is generated.  */
447   enum cpp_normalize_level warn_normalize;
448 
449   /* True to warn about precompiled header files we couldn't use.  */
450   bool warn_invalid_pch;
451 
452   /* True if dependencies should be restored from a precompiled header.  */
453   bool restore_pch_deps;
454 
455   /* Dependency generation.  */
456   struct
457   {
458     /* Style of header dependencies to generate.  */
459     enum cpp_deps_style style;
460 
461     /* Assume missing files are generated files.  */
462     bool missing_files;
463 
464     /* Generate phony targets for each dependency apart from the first
465        one.  */
466     bool phony_targets;
467 
468     /* If true, no dependency is generated on the main file.  */
469     bool ignore_main_file;
470 
471     /* If true, intend to use the preprocessor output (e.g., for compilation)
472        in addition to the dependency info.  */
473     bool need_preprocessor_output;
474   } deps;
475 
476   /* Target-specific features set by the front end or client.  */
477 
478   /* Precision for target CPP arithmetic, target characters, target
479      ints and target wide characters, respectively.  */
480   size_t precision, char_precision, int_precision, wchar_precision;
481 
482   /* True means chars (wide chars) are unsigned.  */
483   bool unsigned_char, unsigned_wchar;
484 
485   /* True if the most significant byte in a word has the lowest
486      address in memory.  */
487   bool bytes_big_endian;
488 
489   /* Nonzero means __STDC__ should have the value 0 in system headers.  */
490   unsigned char stdc_0_in_system_headers;
491 
492   /* True disables tokenization outside of preprocessing directives. */
493   bool directives_only;
494 
495   /* True enables canonicalization of system header file paths. */
496   bool canonical_system_headers;
497 };
498 
499 /* Callback for header lookup for HEADER, which is the name of a
500    source file.  It is used as a method of last resort to find headers
501    that are not otherwise found during the normal include processing.
502    The return value is the malloced name of a header to try and open,
503    if any, or NULL otherwise.  This callback is called only if the
504    header is otherwise unfound.  */
505 typedef const char *(*missing_header_cb)(cpp_reader *, const char *header, cpp_dir **);
506 
507 /* Call backs to cpplib client.  */
508 struct cpp_callbacks
509 {
510   /* Called when a new line of preprocessed output is started.  */
511   void (*line_change) (cpp_reader *, const cpp_token *, int);
512 
513   /* Called when switching to/from a new file.
514      The line_map is for the new file.  It is NULL if there is no new file.
515      (In C this happens when done with <built-in>+<command line> and also
516      when done with a main file.)  This can be used for resource cleanup.  */
517   void (*file_change) (cpp_reader *, const struct line_map *);
518 
519   void (*dir_change) (cpp_reader *, const char *);
520   void (*include) (cpp_reader *, source_location, const unsigned char *,
521 		   const char *, int, const cpp_token **);
522   void (*define) (cpp_reader *, source_location, cpp_hashnode *);
523   void (*undef) (cpp_reader *, source_location, cpp_hashnode *);
524   void (*ident) (cpp_reader *, source_location, const cpp_string *);
525   void (*def_pragma) (cpp_reader *, source_location);
526   int (*valid_pch) (cpp_reader *, const char *, int);
527   void (*read_pch) (cpp_reader *, const char *, int, const char *);
528   missing_header_cb missing_header;
529 
530   /* Context-sensitive macro support.  Returns macro (if any) that should
531      be expanded.  */
532   cpp_hashnode * (*macro_to_expand) (cpp_reader *, const cpp_token *);
533 
534   /* Called to emit a diagnostic.  This callback receives the
535      translated message.  */
536   bool (*error) (cpp_reader *, int, int, source_location, unsigned int,
537 		 const char *, va_list *)
538        ATTRIBUTE_FPTR_PRINTF(6,0);
539 
540   /* Callbacks for when a macro is expanded, or tested (whether
541      defined or not at the time) in #ifdef, #ifndef or "defined".  */
542   void (*used_define) (cpp_reader *, source_location, cpp_hashnode *);
543   void (*used_undef) (cpp_reader *, source_location, cpp_hashnode *);
544   /* Called before #define and #undef or other macro definition
545      changes are processed.  */
546   void (*before_define) (cpp_reader *);
547   /* Called whenever a macro is expanded or tested.
548      Second argument is the location of the start of the current expansion.  */
549   void (*used) (cpp_reader *, source_location, cpp_hashnode *);
550 
551   /* Callback that can change a user builtin into normal macro.  */
552   bool (*user_builtin_macro) (cpp_reader *, cpp_hashnode *);
553 };
554 
555 #ifdef VMS
556 #define INO_T_CPP ino_t ino[3]
557 #else
558 #define INO_T_CPP ino_t ino
559 #endif
560 
561 /* Chain of directories to look for include files in.  */
562 struct cpp_dir
563 {
564   /* NULL-terminated singly-linked list.  */
565   struct cpp_dir *next;
566 
567   /* NAME of the directory, NUL-terminated.  */
568   char *name;
569   unsigned int len;
570 
571   /* One if a system header, two if a system header that has extern
572      "C" guards for C++.  */
573   unsigned char sysp;
574 
575   /* Is this a user-supplied directory? */
576   bool user_supplied_p;
577 
578   /* The canonicalized NAME as determined by lrealpath.  This field
579      is only used by hosts that lack reliable inode numbers.  */
580   char *canonical_name;
581 
582   /* Mapping of file names for this directory for MS-DOS and related
583      platforms.  A NULL-terminated array of (from, to) pairs.  */
584   const char **name_map;
585 
586   /* Routine to construct pathname, given the search path name and the
587      HEADER we are trying to find, return a constructed pathname to
588      try and open.  If this is NULL, the constructed pathname is as
589      constructed by append_file_to_dir.  */
590   char *(*construct) (const char *header, cpp_dir *dir);
591 
592   /* The C front end uses these to recognize duplicated
593      directories in the search path.  */
594   INO_T_CPP;
595   dev_t dev;
596 };
597 
598 /* The structure of a node in the hash table.  The hash table has
599    entries for all identifiers: either macros defined by #define
600    commands (type NT_MACRO), assertions created with #assert
601    (NT_ASSERTION), or neither of the above (NT_VOID).  Builtin macros
602    like __LINE__ are flagged NODE_BUILTIN.  Poisoned identifiers are
603    flagged NODE_POISONED.  NODE_OPERATOR (C++ only) indicates an
604    identifier that behaves like an operator such as "xor".
605    NODE_DIAGNOSTIC is for speed in lex_token: it indicates a
606    diagnostic may be required for this node.  Currently this only
607    applies to __VA_ARGS__, poisoned identifiers, and -Wc++-compat
608    warnings about NODE_OPERATOR.  */
609 
610 /* Hash node flags.  */
611 #define NODE_OPERATOR	(1 << 0)	/* C++ named operator.  */
612 #define NODE_POISONED	(1 << 1)	/* Poisoned identifier.  */
613 #define NODE_BUILTIN	(1 << 2)	/* Builtin macro.  */
614 #define NODE_DIAGNOSTIC (1 << 3)	/* Possible diagnostic when lexed.  */
615 #define NODE_WARN	(1 << 4)	/* Warn if redefined or undefined.  */
616 #define NODE_DISABLED	(1 << 5)	/* A disabled macro.  */
617 #define NODE_MACRO_ARG	(1 << 6)	/* Used during #define processing.  */
618 #define NODE_USED	(1 << 7)	/* Dumped with -dU.  */
619 #define NODE_CONDITIONAL (1 << 8)	/* Conditional macro */
620 #define NODE_WARN_OPERATOR (1 << 9)	/* Warn about C++ named operator.  */
621 
622 /* Different flavors of hash node.  */
623 enum node_type
624 {
625   NT_VOID = 0,	   /* No definition yet.  */
626   NT_MACRO,	   /* A macro of some form.  */
627   NT_ASSERTION	   /* Predicate for #assert.  */
628 };
629 
630 /* Different flavors of builtin macro.  _Pragma is an operator, but we
631    handle it with the builtin code for efficiency reasons.  */
632 enum cpp_builtin_type
633 {
634   BT_SPECLINE = 0,		/* `__LINE__' */
635   BT_DATE,			/* `__DATE__' */
636   BT_FILE,			/* `__FILE__' */
637   BT_BASE_FILE,			/* `__BASE_FILE__' */
638   BT_INCLUDE_LEVEL,		/* `__INCLUDE_LEVEL__' */
639   BT_TIME,			/* `__TIME__' */
640   BT_STDC,			/* `__STDC__' */
641   BT_PRAGMA,			/* `_Pragma' operator */
642   BT_TIMESTAMP,			/* `__TIMESTAMP__' */
643   BT_COUNTER,			/* `__COUNTER__' */
644   BT_FIRST_USER,		/* User defined builtin macros.  */
645   BT_LAST_USER = BT_FIRST_USER + 31
646 };
647 
648 #define CPP_HASHNODE(HNODE)	((cpp_hashnode *) (HNODE))
649 #define HT_NODE(NODE)		((ht_identifier *) (NODE))
650 #define NODE_LEN(NODE)		HT_LEN (&(NODE)->ident)
651 #define NODE_NAME(NODE)		HT_STR (&(NODE)->ident)
652 
653 /* Specify which field, if any, of the union is used.  */
654 
655 enum {
656   NTV_MACRO,
657   NTV_ANSWER,
658   NTV_BUILTIN,
659   NTV_ARGUMENT,
660   NTV_NONE
661 };
662 
663 #define CPP_HASHNODE_VALUE_IDX(HNODE)				\
664   ((HNODE.flags & NODE_MACRO_ARG) ? NTV_ARGUMENT		\
665    : HNODE.type == NT_MACRO ? ((HNODE.flags & NODE_BUILTIN) 	\
666 			       ? NTV_BUILTIN : NTV_MACRO)	\
667    : HNODE.type == NT_ASSERTION ? NTV_ANSWER			\
668    : NTV_NONE)
669 
670 /* The common part of an identifier node shared amongst all 3 C front
671    ends.  Also used to store CPP identifiers, which are a superset of
672    identifiers in the grammatical sense.  */
673 
674 union GTY(()) _cpp_hashnode_value {
675   /* If a macro.  */
676   cpp_macro * GTY((tag ("NTV_MACRO"))) macro;
677   /* Answers to an assertion.  */
678   struct answer * GTY ((tag ("NTV_ANSWER"))) answers;
679   /* Code for a builtin macro.  */
680   enum cpp_builtin_type GTY ((tag ("NTV_BUILTIN"))) builtin;
681   /* Macro argument index.  */
682   unsigned short GTY ((tag ("NTV_ARGUMENT"))) arg_index;
683 };
684 
685 struct GTY(()) cpp_hashnode {
686   struct ht_identifier ident;
687   unsigned int is_directive : 1;
688   unsigned int directive_index : 7;	/* If is_directive,
689 					   then index into directive table.
690 					   Otherwise, a NODE_OPERATOR.  */
691   unsigned char rid_code;		/* Rid code - for front ends.  */
692   ENUM_BITFIELD(node_type) type : 6;	/* CPP node type.  */
693   unsigned int flags : 10;		/* CPP flags.  */
694 
695   union _cpp_hashnode_value GTY ((desc ("CPP_HASHNODE_VALUE_IDX (%1)"))) value;
696 };
697 
698 /* Call this first to get a handle to pass to other functions.
699 
700    If you want cpplib to manage its own hashtable, pass in a NULL
701    pointer.  Otherwise you should pass in an initialized hash table
702    that cpplib will share; this technique is used by the C front
703    ends.  */
704 extern cpp_reader *cpp_create_reader (enum c_lang, struct ht *,
705 				      struct line_maps *);
706 
707 /* Reset the cpp_reader's line_map.  This is only used after reading a
708    PCH file.  */
709 extern void cpp_set_line_map (cpp_reader *, struct line_maps *);
710 
711 /* Call this to change the selected language standard (e.g. because of
712    command line options).  */
713 extern void cpp_set_lang (cpp_reader *, enum c_lang);
714 
715 /* Set the include paths.  */
716 extern void cpp_set_include_chains (cpp_reader *, cpp_dir *, cpp_dir *, int);
717 
718 /* Call these to get pointers to the options, callback, and deps
719    structures for a given reader.  These pointers are good until you
720    call cpp_finish on that reader.  You can either edit the callbacks
721    through the pointer returned from cpp_get_callbacks, or set them
722    with cpp_set_callbacks.  */
723 extern cpp_options *cpp_get_options (cpp_reader *);
724 extern cpp_callbacks *cpp_get_callbacks (cpp_reader *);
725 extern void cpp_set_callbacks (cpp_reader *, cpp_callbacks *);
726 extern struct deps *cpp_get_deps (cpp_reader *);
727 
728 /* This function reads the file, but does not start preprocessing.  It
729    returns the name of the original file; this is the same as the
730    input file, except for preprocessed input.  This will generate at
731    least one file change callback, and possibly a line change callback
732    too.  If there was an error opening the file, it returns NULL.  */
733 extern const char *cpp_read_main_file (cpp_reader *, const char *);
734 
735 /* Set up built-ins with special behavior.  Use cpp_init_builtins()
736    instead unless your know what you are doing.  */
737 extern void cpp_init_special_builtins (cpp_reader *);
738 
739 /* Set up built-ins like __FILE__.  */
740 extern void cpp_init_builtins (cpp_reader *, int);
741 
742 /* This is called after options have been parsed, and partially
743    processed.  */
744 extern void cpp_post_options (cpp_reader *);
745 
746 /* Set up translation to the target character set.  */
747 extern void cpp_init_iconv (cpp_reader *);
748 
749 /* Call this to finish preprocessing.  If you requested dependency
750    generation, pass an open stream to write the information to,
751    otherwise NULL.  It is your responsibility to close the stream.  */
752 extern void cpp_finish (cpp_reader *, FILE *deps_stream);
753 
754 /* Call this to release the handle at the end of preprocessing.  Any
755    use of the handle after this function returns is invalid.  */
756 extern void cpp_destroy (cpp_reader *);
757 
758 extern unsigned int cpp_token_len (const cpp_token *);
759 extern unsigned char *cpp_token_as_text (cpp_reader *, const cpp_token *);
760 extern unsigned char *cpp_spell_token (cpp_reader *, const cpp_token *,
761 				       unsigned char *, bool);
762 extern void cpp_register_pragma (cpp_reader *, const char *, const char *,
763 				 void (*) (cpp_reader *), bool);
764 extern void cpp_register_deferred_pragma (cpp_reader *, const char *,
765 					  const char *, unsigned, bool, bool);
766 extern int cpp_avoid_paste (cpp_reader *, const cpp_token *,
767 			    const cpp_token *);
768 extern const cpp_token *cpp_get_token (cpp_reader *);
769 extern const cpp_token *cpp_get_token_with_location (cpp_reader *,
770 						     source_location *);
771 extern const unsigned char *cpp_macro_definition (cpp_reader *,
772 						  cpp_hashnode *);
773 extern void _cpp_backup_tokens (cpp_reader *, unsigned int);
774 extern const cpp_token *cpp_peek_token (cpp_reader *, int);
775 
776 /* Evaluate a CPP_*CHAR* token.  */
777 extern cppchar_t cpp_interpret_charconst (cpp_reader *, const cpp_token *,
778 					  unsigned int *, int *);
779 /* Evaluate a vector of CPP_*STRING* tokens.  */
780 extern bool cpp_interpret_string (cpp_reader *,
781 				  const cpp_string *, size_t,
782 				  cpp_string *, enum cpp_ttype);
783 extern bool cpp_interpret_string_notranslate (cpp_reader *,
784 					      const cpp_string *, size_t,
785 					      cpp_string *, enum cpp_ttype);
786 
787 /* Convert a host character constant to the execution character set.  */
788 extern cppchar_t cpp_host_to_exec_charset (cpp_reader *, cppchar_t);
789 
790 /* Used to register macros and assertions, perhaps from the command line.
791    The text is the same as the command line argument.  */
792 extern void cpp_define (cpp_reader *, const char *);
793 extern void cpp_define_formatted (cpp_reader *pfile,
794 				  const char *fmt, ...) ATTRIBUTE_PRINTF_2;
795 extern void cpp_assert (cpp_reader *, const char *);
796 extern void cpp_undef (cpp_reader *, const char *);
797 extern void cpp_unassert (cpp_reader *, const char *);
798 
799 /* Undefine all macros and assertions.  */
800 extern void cpp_undef_all (cpp_reader *);
801 
802 extern cpp_buffer *cpp_push_buffer (cpp_reader *, const unsigned char *,
803 				    size_t, int);
804 extern int cpp_defined (cpp_reader *, const unsigned char *, int);
805 
806 /* A preprocessing number.  Code assumes that any unused high bits of
807    the double integer are set to zero.  */
808 typedef unsigned HOST_WIDE_INT cpp_num_part;
809 typedef struct cpp_num cpp_num;
810 struct cpp_num
811 {
812   cpp_num_part high;
813   cpp_num_part low;
814   bool unsignedp;  /* True if value should be treated as unsigned.  */
815   bool overflow;   /* True if the most recent calculation overflowed.  */
816 };
817 
818 /* cpplib provides two interfaces for interpretation of preprocessing
819    numbers.
820 
821    cpp_classify_number categorizes numeric constants according to
822    their field (integer, floating point, or invalid), radix (decimal,
823    octal, hexadecimal), and type suffixes.  */
824 
825 #define CPP_N_CATEGORY  0x000F
826 #define CPP_N_INVALID	0x0000
827 #define CPP_N_INTEGER	0x0001
828 #define CPP_N_FLOATING	0x0002
829 
830 #define CPP_N_WIDTH	0x00F0
831 #define CPP_N_SMALL	0x0010	/* int, float, shrot _Fract/Accum  */
832 #define CPP_N_MEDIUM	0x0020	/* long, double, long _Fract/_Accum.  */
833 #define CPP_N_LARGE	0x0040	/* long long, long double,
834 				   long long _Fract/Accum.  */
835 
836 #define CPP_N_WIDTH_MD	0xF0000	/* machine defined.  */
837 #define CPP_N_MD_W	0x10000
838 #define CPP_N_MD_Q	0x20000
839 
840 #define CPP_N_RADIX	0x0F00
841 #define CPP_N_DECIMAL	0x0100
842 #define CPP_N_HEX	0x0200
843 #define CPP_N_OCTAL	0x0400
844 #define CPP_N_BINARY	0x0800
845 
846 #define CPP_N_UNSIGNED	0x1000	/* Properties.  */
847 #define CPP_N_IMAGINARY	0x2000
848 #define CPP_N_DFLOAT	0x4000
849 #define CPP_N_DEFAULT	0x8000
850 
851 #define CPP_N_FRACT	0x100000 /* Fract types.  */
852 #define CPP_N_ACCUM	0x200000 /* Accum types.  */
853 
854 #define CPP_N_USERDEF	0x1000000 /* C++0x user-defined literal.  */
855 
856 /* Classify a CPP_NUMBER token.  The return value is a combination of
857    the flags from the above sets.  */
858 extern unsigned cpp_classify_number (cpp_reader *, const cpp_token *,
859 				     const char **, source_location);
860 
861 /* Return the classification flags for a float suffix.  */
862 extern unsigned int cpp_interpret_float_suffix (cpp_reader *, const char *,
863 						size_t);
864 
865 /* Return the classification flags for an int suffix.  */
866 extern unsigned int cpp_interpret_int_suffix (cpp_reader *, const char *,
867 					      size_t);
868 
869 /* Evaluate a token classified as category CPP_N_INTEGER.  */
870 extern cpp_num cpp_interpret_integer (cpp_reader *, const cpp_token *,
871 				      unsigned int);
872 
873 /* Sign extend a number, with PRECISION significant bits and all
874    others assumed clear, to fill out a cpp_num structure.  */
875 cpp_num cpp_num_sign_extend (cpp_num, size_t);
876 
877 /* Diagnostic levels.  To get a diagnostic without associating a
878    position in the translation unit with it, use cpp_error_with_line
879    with a line number of zero.  */
880 
881 enum {
882   /* Warning, an error with -Werror.  */
883   CPP_DL_WARNING = 0,
884   /* Same as CPP_DL_WARNING, except it is not suppressed in system headers.  */
885   CPP_DL_WARNING_SYSHDR,
886   /* Warning, an error with -pedantic-errors or -Werror.  */
887   CPP_DL_PEDWARN,
888   /* An error.  */
889   CPP_DL_ERROR,
890   /* An internal consistency check failed.  Prints "internal error: ",
891      otherwise the same as CPP_DL_ERROR.  */
892   CPP_DL_ICE,
893   /* An informative note following a warning.  */
894   CPP_DL_NOTE,
895   /* A fatal error.  */
896   CPP_DL_FATAL
897 };
898 
899 /* Warning reason codes. Use a reason code of zero for unclassified warnings
900    and errors that are not warnings.  */
901 enum {
902   CPP_W_NONE = 0,
903   CPP_W_DEPRECATED,
904   CPP_W_COMMENTS,
905   CPP_W_MISSING_INCLUDE_DIRS,
906   CPP_W_TRIGRAPHS,
907   CPP_W_MULTICHAR,
908   CPP_W_TRADITIONAL,
909   CPP_W_LONG_LONG,
910   CPP_W_ENDIF_LABELS,
911   CPP_W_NUM_SIGN_CHANGE,
912   CPP_W_VARIADIC_MACROS,
913   CPP_W_BUILTIN_MACRO_REDEFINED,
914   CPP_W_DOLLARS,
915   CPP_W_UNDEF,
916   CPP_W_UNUSED_MACROS,
917   CPP_W_CXX_OPERATOR_NAMES,
918   CPP_W_NORMALIZE,
919   CPP_W_INVALID_PCH,
920   CPP_W_WARNING_DIRECTIVE,
921   CPP_W_LITERAL_SUFFIX
922 };
923 
924 /* Output a diagnostic of some kind.  */
925 extern bool cpp_error (cpp_reader *, int, const char *msgid, ...)
926   ATTRIBUTE_PRINTF_3;
927 extern bool cpp_warning (cpp_reader *, int, const char *msgid, ...)
928   ATTRIBUTE_PRINTF_3;
929 extern bool cpp_pedwarning (cpp_reader *, int, const char *msgid, ...)
930   ATTRIBUTE_PRINTF_3;
931 extern bool cpp_warning_syshdr (cpp_reader *, int, const char *msgid, ...)
932   ATTRIBUTE_PRINTF_3;
933 
934 /* Output a diagnostic with "MSGID: " preceding the
935    error string of errno.  No location is printed.  */
936 extern bool cpp_errno (cpp_reader *, int, const char *msgid);
937 
938 /* Same as cpp_error, except additionally specifies a position as a
939    (translation unit) physical line and physical column.  If the line is
940    zero, then no location is printed.  */
941 extern bool cpp_error_with_line (cpp_reader *, int, source_location,
942                                  unsigned, const char *msgid, ...)
943   ATTRIBUTE_PRINTF_5;
944 extern bool cpp_warning_with_line (cpp_reader *, int, source_location,
945                                    unsigned, const char *msgid, ...)
946   ATTRIBUTE_PRINTF_5;
947 extern bool cpp_pedwarning_with_line (cpp_reader *, int, source_location,
948                                       unsigned, const char *msgid, ...)
949   ATTRIBUTE_PRINTF_5;
950 extern bool cpp_warning_with_line_syshdr (cpp_reader *, int, source_location,
951                                           unsigned, const char *msgid, ...)
952   ATTRIBUTE_PRINTF_5;
953 
954 /* In lex.c */
955 extern int cpp_ideq (const cpp_token *, const char *);
956 extern void cpp_output_line (cpp_reader *, FILE *);
957 extern unsigned char *cpp_output_line_to_string (cpp_reader *,
958 						 const unsigned char *);
959 extern void cpp_output_token (const cpp_token *, FILE *);
960 extern const char *cpp_type2name (enum cpp_ttype, unsigned char flags);
961 /* Returns the value of an escape sequence, truncated to the correct
962    target precision.  PSTR points to the input pointer, which is just
963    after the backslash.  LIMIT is how much text we have.  WIDE is true
964    if the escape sequence is part of a wide character constant or
965    string literal.  Handles all relevant diagnostics.  */
966 extern cppchar_t cpp_parse_escape (cpp_reader *, const unsigned char ** pstr,
967 				   const unsigned char *limit, int wide);
968 
969 /* Structure used to hold a comment block at a given location in the
970    source code.  */
971 
972 typedef struct
973 {
974   /* Text of the comment including the terminators.  */
975   char *comment;
976 
977   /* source location for the given comment.  */
978   source_location sloc;
979 } cpp_comment;
980 
981 /* Structure holding all comments for a given cpp_reader.  */
982 
983 typedef struct
984 {
985   /* table of comment entries.  */
986   cpp_comment *entries;
987 
988   /* number of actual entries entered in the table.  */
989   int count;
990 
991   /* number of entries allocated currently.  */
992   int allocated;
993 } cpp_comment_table;
994 
995 /* Returns the table of comments encountered by the preprocessor. This
996    table is only populated when pfile->state.save_comments is true. */
997 extern cpp_comment_table *cpp_get_comments (cpp_reader *);
998 
999 /* In hash.c */
1000 
1001 /* Lookup an identifier in the hashtable.  Puts the identifier in the
1002    table if it is not already there.  */
1003 extern cpp_hashnode *cpp_lookup (cpp_reader *, const unsigned char *,
1004 				 unsigned int);
1005 
1006 typedef int (*cpp_cb) (cpp_reader *, cpp_hashnode *, void *);
1007 extern void cpp_forall_identifiers (cpp_reader *, cpp_cb, void *);
1008 
1009 /* In macro.c */
1010 extern void cpp_scan_nooutput (cpp_reader *);
1011 extern int  cpp_sys_macro_p (cpp_reader *);
1012 extern unsigned char *cpp_quote_string (unsigned char *, const unsigned char *,
1013 					unsigned int);
1014 
1015 /* In files.c */
1016 extern bool cpp_included (cpp_reader *, const char *);
1017 extern bool cpp_included_before (cpp_reader *, const char *, source_location);
1018 extern void cpp_make_system_header (cpp_reader *, int, int);
1019 extern bool cpp_push_include (cpp_reader *, const char *);
1020 extern bool cpp_push_default_include (cpp_reader *, const char *);
1021 extern void cpp_change_file (cpp_reader *, enum lc_reason, const char *);
1022 extern const char *cpp_get_path (struct _cpp_file *);
1023 extern cpp_dir *cpp_get_dir (struct _cpp_file *);
1024 extern cpp_buffer *cpp_get_buffer (cpp_reader *);
1025 extern struct _cpp_file *cpp_get_file (cpp_buffer *);
1026 extern cpp_buffer *cpp_get_prev (cpp_buffer *);
1027 extern void cpp_clear_file_cache (cpp_reader *);
1028 
1029 /* In pch.c */
1030 struct save_macro_data;
1031 extern int cpp_save_state (cpp_reader *, FILE *);
1032 extern int cpp_write_pch_deps (cpp_reader *, FILE *);
1033 extern int cpp_write_pch_state (cpp_reader *, FILE *);
1034 extern int cpp_valid_state (cpp_reader *, const char *, int);
1035 extern void cpp_prepare_state (cpp_reader *, struct save_macro_data **);
1036 extern int cpp_read_state (cpp_reader *, const char *, FILE *,
1037 			   struct save_macro_data *);
1038 
1039 /* In lex.c */
1040 extern void cpp_force_token_locations (cpp_reader *, source_location *);
1041 extern void cpp_stop_forcing_token_locations (cpp_reader *);
1042 
1043 /* In expr.c */
1044 extern enum cpp_ttype cpp_userdef_string_remove_type
1045   (enum cpp_ttype type);
1046 extern enum cpp_ttype cpp_userdef_string_add_type
1047   (enum cpp_ttype type);
1048 extern enum cpp_ttype cpp_userdef_char_remove_type
1049   (enum cpp_ttype type);
1050 extern enum cpp_ttype cpp_userdef_char_add_type
1051   (enum cpp_ttype type);
1052 extern bool cpp_userdef_string_p
1053   (enum cpp_ttype type);
1054 extern bool cpp_userdef_char_p
1055   (enum cpp_ttype type);
1056 extern const char * cpp_get_userdef_suffix
1057   (const cpp_token *);
1058 
1059 #endif /* ! LIBCPP_CPPLIB_H */
1060