1 /* Process source files and output type information.
2 Copyright (C) 2002-2023 Free Software Foundation, Inc.
3
4 This file is part of GCC.
5
6 GCC is free software; you can redistribute it and/or modify it under
7 the terms of the GNU General Public License as published by the Free
8 Software Foundation; either version 3, or (at your option) any later
9 version.
10
11 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
12 WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 for more details.
15
16 You should have received a copy of the GNU General Public License
17 along with GCC; see the file COPYING3. If not see
18 <http://www.gnu.org/licenses/>. */
19
20 #ifndef GCC_GENGTYPE_H
21 #define GCC_GENGTYPE_H
22
23 #define obstack_chunk_alloc xmalloc
24 #define obstack_chunk_free free
25 #define OBSTACK_CHUNK_SIZE 0
26
27 /* Sets of accepted source languages like C, C++, Ada... are
28 represented by a bitmap. */
29 typedef unsigned lang_bitmap;
30
31 /* Variable length structure representing an input file. A hash table
32 ensure uniqueness for a given input file name. The only function
33 allocating input_file-s is input_file_by_name. */
34 struct input_file_st
35 {
36 struct outf* inpoutf; /* Cached corresponding output file, computed
37 in get_output_file_with_visibility. */
38 lang_bitmap inpbitmap; /* The set of languages using this file. */
39 bool inpisplugin; /* Flag set for plugin input files. */
40 char inpname[1]; /* A variable-length array, ended by a null
41 char. */
42 };
43 typedef struct input_file_st input_file;
44
45 /* A file position, mostly for error messages.
46 The FILE element may be compared using pointer equality. */
47 struct fileloc
48 {
49 const input_file *file;
50 int line;
51 };
52
53
54 /* Table of all input files and its size. */
55 extern const input_file** gt_files;
56 extern size_t num_gt_files;
57
58 /* Table of headers to be included in gtype-desc.cc that are generated
59 during the build. These are identified as "./<filename>.h". */
60 extern const char **build_headers;
61 extern size_t num_build_headers;
62
63 /* A number of places use the name of this "gengtype.cc" file for a
64 location for things that we can't rely on the source to define. We
65 also need to refer to the "system.h" file specifically. These two
66 pointers are initialized early in main. */
67 extern input_file* this_file;
68 extern input_file* system_h_file;
69
70 /* Retrieve or create the input_file for a given name, which is a file
71 path. This is the only function allocating input_file-s and it is
72 hash-consing them. */
73 input_file* input_file_by_name (const char* name);
74
75 /* For F an input_file, return the relative path to F from $(srcdir)
76 if the latter is a prefix in F, NULL otherwise. */
77 const char *get_file_srcdir_relative_path (const input_file *inpf);
78
79 /* Get the name of an input file. */
80 inline const char*
81 get_input_file_name (const input_file *inpf)
82 {
83 if (inpf)
84 return inpf->inpname;
85 return NULL;
86 }
87
88 /* Return a bitmap which has bit `1 << BASE_FILE_<lang>' set iff
89 INPUT_FILE is used by <lang>.
90
91 This function should be written to assume that a file _is_ used
92 if the situation is unclear. If it wrongly assumes a file _is_ used,
93 a linker error will result. If it wrongly assumes a file _is not_ used,
94 some GC roots may be missed, which is a much harder-to-debug problem.
95 */
96
97 inline lang_bitmap
98 get_lang_bitmap (const input_file* inpf)
99 {
100 if (inpf == NULL)
101 return 0;
102 return inpf->inpbitmap;
103 }
104
105 /* Set the bitmap returned by get_lang_bitmap. The only legitimate
106 callers of this function are read_input_list & read_state_*. */
107 inline void
108 set_lang_bitmap (input_file* inpf, lang_bitmap n)
109 {
110 gcc_assert (inpf);
111 inpf->inpbitmap = n;
112 }
113
114 /* Vector of per-language directories. */
115 extern const char **lang_dir_names;
116 extern size_t num_lang_dirs;
117
118 /* Data types handed around within, but opaque to, the lexer and parser. */
119 typedef struct pair *pair_p;
120 typedef struct type *type_p;
121 typedef const struct type *const_type_p;
122 typedef struct options *options_p;
123
124 /* Variables used to communicate between the lexer and the parser. */
125 extern int lexer_toplevel_done;
126 extern struct fileloc lexer_line;
127
128 /* Various things, organized as linked lists, needed both in
129 gengtype.cc & in gengtype-state.cc files. */
130 extern pair_p typedefs;
131 extern type_p structures;
132 extern pair_p variables;
133
134 /* An enum for distinguishing GGC vs PCH. */
135
136 enum write_types_kinds
137 {
138 WTK_GGC,
139 WTK_PCH,
140
141 NUM_WTK
142 };
143
144 /* Discrimating kind of types we can understand. */
145
146 enum typekind {
147 TYPE_NONE=0, /* Never used, so zeroed memory is invalid. */
148 TYPE_UNDEFINED, /* We have not yet seen a definition for this type.
149 If a type is still undefined when generating code,
150 an error will be generated. */
151 TYPE_SCALAR, /* Scalar types like char. */
152 TYPE_STRING, /* The string type. */
153 TYPE_STRUCT, /* Type for GTY-ed structs. */
154 TYPE_UNION, /* Type for GTY-ed discriminated unions. */
155 TYPE_POINTER, /* Pointer type to GTY-ed type. */
156 TYPE_ARRAY, /* Array of GTY-ed types. */
157 TYPE_CALLBACK, /* A function pointer that needs relocation if
158 the executable has been loaded at a different
159 address. */
160 TYPE_LANG_STRUCT, /* GCC front-end language specific structs.
161 Various languages may have homonymous but
162 different structs. */
163 TYPE_USER_STRUCT /* User defined type. Walkers and markers for
164 this type are assumed to be provided by the
165 user. */
166 };
167
168 /* Discriminating kind for options. */
169 enum option_kind {
170 OPTION_NONE=0, /* Never used, so zeroed memory is invalid. */
171 OPTION_STRING, /* A string-valued option. Most options are
172 strings. */
173 OPTION_TYPE, /* A type-valued option. */
174 OPTION_NESTED /* Option data for 'nested_ptr'. */
175 };
176
177
178 /* A way to pass data through to the output end. */
179 struct options {
180 struct options *next; /* next option of the same pair. */
181 const char *name; /* GTY option name. */
182 enum option_kind kind; /* discriminating option kind. */
183 union {
184 const char* string; /* When OPTION_STRING. */
185 type_p type; /* When OPTION_TYPE. */
186 struct nested_ptr_data* nested; /* when OPTION_NESTED. */
187 } info;
188 };
189
190
191 /* Option data for the 'nested_ptr' option. */
192 struct nested_ptr_data {
193 type_p type;
194 const char *convert_to;
195 const char *convert_from;
196 };
197
198 /* Some functions to create various options structures with name NAME
199 and info INFO. NEXT is the next option in the chain. */
200
201 /* Create a string option. */
202 options_p create_string_option (options_p next, const char* name,
203 const char* info);
204
205 /* Create a type option. */
206 options_p create_type_option (options_p next, const char* name,
207 type_p info);
208
209 /* Create a nested option. */
210 options_p create_nested_option (options_p next, const char* name,
211 struct nested_ptr_data* info);
212
213 /* Create a nested pointer option. */
214 options_p create_nested_ptr_option (options_p next, type_p t,
215 const char *to, const char *from);
216
217 /* A name and a type. */
218 struct pair {
219 pair_p next; /* The next pair in the linked list. */
220 const char *name; /* The defined name. */
221 type_p type; /* Its GTY-ed type. */
222 struct fileloc line; /* The file location. */
223 options_p opt; /* GTY options, as a linked list. */
224 };
225
226 /* Usage information for GTY-ed types. Gengtype has to care only of
227 used GTY-ed types. Types are initially unused, and their usage is
228 computed by set_gc_used_type and set_gc_used functions. */
229
230 enum gc_used_enum {
231
232 /* We need that zeroed types are initially unused. */
233 GC_UNUSED=0,
234
235 /* The GTY-ed type is used, e.g by a GTY-ed variable or a field
236 inside a GTY-ed used type. */
237 GC_USED,
238
239 /* For GTY-ed structures whose definitions we haven't seen so far
240 when we encounter a pointer to it that is annotated with
241 ``maybe_undef''. If after reading in everything we don't have
242 source file information for it, we assume that it never has been
243 defined. */
244 GC_MAYBE_POINTED_TO,
245
246 /* For known GTY-ed structures which are pointed to by GTY-ed
247 variables or fields. */
248 GC_POINTED_TO
249 };
250
251 /* Our type structure describes all types handled by gengtype. */
252 struct type {
253 /* Discriminating kind, cannot be TYPE_NONE. */
254 enum typekind kind;
255
256 /* For top-level structs or unions, the 'next' field links the
257 global list 'structures'; for lang_structs, their homonymous structs are
258 linked using this 'next' field. The homonymous list starts at the
259 s.lang_struct field of the lang_struct. See the new_structure function
260 for details. This is tricky! */
261 type_p next;
262
263 /* State number used when writing & reading the persistent state. A
264 type with a positive number has already been written. For ease
265 of debugging, newly allocated types have a unique negative
266 number. */
267 int state_number;
268
269 /* Each GTY-ed type which is pointed to by some GTY-ed type knows
270 the GTY pointer type pointing to it. See create_pointer
271 function. */
272 type_p pointer_to;
273
274 /* Type usage information, computed by set_gc_used_type and
275 set_gc_used functions. */
276 enum gc_used_enum gc_used;
277
278 /* The following union is discriminated by the 'kind' field above. */
279 union {
280 /* TYPE__NONE is impossible. */
281
282 /* when TYPE_POINTER: */
283 type_p p;
284
285 /* when TYPE_STRUCT or TYPE_UNION or TYPE_LANG_STRUCT, we have an
286 aggregate type containing fields: */
287 struct {
288 const char *tag; /* the aggregate tag, if any. */
289 struct fileloc line; /* the source location. */
290 pair_p fields; /* the linked list of fields. */
291 options_p opt; /* the GTY options if any. */
292 lang_bitmap bitmap; /* the set of front-end languages
293 using that GTY-ed aggregate. */
294 /* For TYPE_LANG_STRUCT, the lang_struct field gives the first
295 element of a linked list of homonymous struct or union types.
296 Within this list, each homonymous type has as its lang_struct
297 field the original TYPE_LANG_STRUCT type. This is a dirty
298 trick, see the new_structure function for details. */
299 type_p lang_struct;
300
301 type_p base_class; /* the parent class, if any. */
302
303 /* The following two fields are not serialized in state files, and
304 are instead reconstructed on load. */
305
306 /* The head of a singly-linked list of immediate descendents in
307 the inheritance hierarchy. */
308 type_p first_subclass;
309 /* The next in that list. */
310 type_p next_sibling_class;
311
312 /* Have we already written ggc/pch user func for ptr to this?
313 (in write_user_func_for_structure_ptr). */
314 bool wrote_user_func_for_ptr[NUM_WTK];
315 } s;
316
317 /* when TYPE_SCALAR: */
318 bool scalar_is_char;
319
320 /* when TYPE_ARRAY: */
321 struct {
322 type_p p; /* The array component type. */
323 const char *len; /* The string if any giving its length. */
324 } a;
325
326 } u;
327 };
328
329 /* The one and only TYPE_STRING. */
330 extern struct type string_type;
331
332 /* The two and only TYPE_SCALARs. Their u.scalar_is_char flags are
333 set early in main. */
334 extern struct type scalar_nonchar;
335 extern struct type scalar_char;
336
337 /* The one and only TYPE_CALLBACK. */
338 extern struct type callback_type;
339
340 /* Test if a type is a union, either a plain one or a language
341 specific one. */
342 #define UNION_P(x) \
343 ((x)->kind == TYPE_UNION \
344 || ((x)->kind == TYPE_LANG_STRUCT \
345 && (x)->u.s.lang_struct->kind == TYPE_UNION))
346
347 /* Test if a type is a union or a structure, perhaps a language
348 specific one. */
349 inline bool
350 union_or_struct_p (enum typekind kind)
351 {
352 return (kind == TYPE_UNION
353 || kind == TYPE_STRUCT
354 || kind == TYPE_LANG_STRUCT
355 || kind == TYPE_USER_STRUCT);
356 }
357
358 inline bool
359 union_or_struct_p (const_type_p x)
360 {
361 return union_or_struct_p (x->kind);
362 }
363
364 /* Give the file location of a type, if any. */
365 inline struct fileloc*
366 type_fileloc (type_p t)
367 {
368 if (!t)
369 return NULL;
370 if (union_or_struct_p (t))
371 return &t->u.s.line;
372 return NULL;
373 }
374
375 /* Structure representing an output file. */
376 struct outf
377 {
378 struct outf *next;
379 const char *name;
380 size_t buflength;
381 size_t bufused;
382 char *buf;
383 };
384 typedef struct outf *outf_p;
385
386 /* The list of output files. */
387 extern outf_p output_files;
388
389 /* The output header file that is included into pretty much every
390 source file. */
391 extern outf_p header_file;
392
393 /* Print, like fprintf, to O. No-op if O is NULL. */
394 void
395 oprintf (outf_p o, const char *S, ...)
396 ATTRIBUTE_PRINTF_2;
397
398 /* An output file, suitable for definitions, that can see declarations
399 made in INPF and is linked into every language that uses INPF. May
400 return NULL in plugin mode. The INPF argument is almost const, but
401 since the result is cached in its inpoutf field it cannot be
402 declared const. */
403 outf_p get_output_file_with_visibility (input_file* inpf);
404
405 /* The name of an output file, suitable for definitions, that can see
406 declarations made in INPF and is linked into every language that
407 uses INPF. May return NULL. */
408 const char *get_output_file_name (input_file *inpf);
409
410
411 /* Source directory. */
412 extern const char *srcdir; /* (-S) program argument. */
413
414 /* Length of srcdir name. */
415 extern size_t srcdir_len;
416
417 /* Variable used for reading and writing the state. */
418 extern const char *read_state_filename; /* (-r) program argument. */
419 extern const char *write_state_filename; /* (-w) program argument. */
420
421 /* Functions reading and writing the entire gengtype state, called from
422 main, and implemented in file gengtype-state.cc. */
423 void read_state (const char* path);
424 /* Write the state, and update the state_number field in types. */
425 void write_state (const char* path);
426
427
428 /* Print an error message. */
429 extern void error_at_line
430 (const struct fileloc *pos, const char *msg, ...) ATTRIBUTE_PRINTF_2;
431
432 /* Constructor routines for types. */
433 extern void do_typedef (const char *s, type_p t, struct fileloc *pos);
434 extern void do_scalar_typedef (const char *s, struct fileloc *pos);
435 extern type_p resolve_typedef (const char *s, struct fileloc *pos);
436 extern void add_subclass (type_p base, type_p subclass);
437 extern type_p new_structure (const char *name, enum typekind kind,
438 struct fileloc *pos, pair_p fields,
439 options_p o, type_p base);
440 type_p create_user_defined_type (const char *, struct fileloc *);
441 extern type_p find_structure (const char *s, enum typekind kind);
442 extern type_p create_scalar_type (const char *name);
443 extern type_p create_pointer (type_p t);
444 extern type_p create_array (type_p t, const char *len);
445 extern pair_p create_field_at (pair_p next, type_p type,
446 const char *name, options_p opt,
447 struct fileloc *pos);
448 extern pair_p nreverse_pairs (pair_p list);
449 extern type_p adjust_field_type (type_p, options_p);
450 extern void note_variable (const char *s, type_p t, options_p o,
451 struct fileloc *pos);
452
453 /* Lexer and parser routines. */
454 extern int yylex (const char **yylval);
455 extern void yybegin (const char *fname);
456 extern void yyend (void);
457 extern void parse_file (const char *name);
458 extern bool hit_error;
459
460 /* Token codes. */
461 enum gty_token
462 {
463 EOF_TOKEN = 0,
464
465 /* Per standard convention, codes in the range (0, UCHAR_MAX]
466 represent single characters with those character codes. */
467 CHAR_TOKEN_OFFSET = UCHAR_MAX + 1,
468 GTY_TOKEN = CHAR_TOKEN_OFFSET,
469 TYPEDEF,
470 EXTERN,
471 STATIC,
472 UNION,
473 STRUCT,
474 ENUM,
475 ELLIPSIS,
476 PTR_ALIAS,
477 NESTED_PTR,
478 USER_GTY,
479 NUM,
480 SCALAR,
481 ID,
482 STRING,
483 CHAR,
484 ARRAY,
485 IGNORABLE_CXX_KEYWORD,
486
487 /* print_token assumes that any token >= FIRST_TOKEN_WITH_VALUE may have
488 a meaningful value to be printed. */
489 FIRST_TOKEN_WITH_VALUE = USER_GTY
490 };
491
492
493 /* Level for verbose messages, e.g. output file generation... */
494 extern int verbosity_level; /* (-v) program argument. */
495
496 /* For debugging purposes we provide two flags. */
497
498 /* Dump everything to understand gengtype's state. Might be useful to
499 gengtype users. */
500 extern int do_dump; /* (-d) program argument. */
501
502 /* Trace the execution by many DBGPRINTF (with the position inside
503 gengtype source code). Only useful to debug gengtype itself. */
504 extern int do_debug; /* (-D) program argument. */
505
506 #define DBGPRINTF(Fmt,...) do {if (do_debug) \
507 fprintf (stderr, "%s:%d: " Fmt "\n", \
508 lbasename (__FILE__),__LINE__, ##__VA_ARGS__);} while (0)
509 void dbgprint_count_type_at (const char *, int, const char *, type_p);
510 #define DBGPRINT_COUNT_TYPE(Msg,Ty) do {if (do_debug) \
511 dbgprint_count_type_at (__FILE__, __LINE__, Msg, Ty);}while (0)
512
513 #define FOR_ALL_INHERITED_FIELDS(TYPE, FIELD_VAR) \
514 for (type_p sub = (TYPE); sub; sub = sub->u.s.base_class) \
515 for (FIELD_VAR = sub->u.s.fields; FIELD_VAR; FIELD_VAR = FIELD_VAR->next)
516
517 extern bool
518 opts_have (options_p opts, const char *str);
519
520
521 #endif