1 /* script-c.h -- C interface for linker scripts in gold.  */
2 
3 /* Copyright (C) 2006-2014 Free Software Foundation, Inc.
4    Written by Ian Lance Taylor <iant@google.com>.
5 
6    This file is part of gold.
7 
8    This program is free software; you can redistribute it and/or modify
9    it under the terms of the GNU General Public License as published by
10    the Free Software Foundation; either version 3 of the License, or
11    (at your option) any later version.
12 
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.
17 
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, Inc., 51 Franklin Street - Fifth Floor, Boston,
21    MA 02110-1301, USA.  */
22 
23 /* This file exists so that both the bison parser and script.cc can
24    include it, so that they can communicate back and forth.  */
25 
26 #ifndef GOLD_SCRIPT_C_H
27 #define GOLD_SCRIPT_C_H
28 
29 #ifdef __cplusplus
30 #include <vector>
31 #include <string>
32 #endif
33 
34 #ifdef __cplusplus
35 
36 // For the C++ code we declare the various supporting structures in
37 // the gold namespace.  For the C code we declare it at the top level.
38 // The namespace level should not affect the layout of the structure.
39 
40 namespace gold
41 {
42 #endif
43 
44 /* A string value for the bison parser.  */
45 
46 struct Parser_string
47 {
48   const char* value;
49   size_t length;
50 };
51 
52 /* The expression functions deal with pointers to Expression objects.
53    Since the bison parser generates C code, this is a hack to keep the
54    C++ code type safe.  This hacks assumes that all pointers look
55    alike.  */
56 
57 #ifdef __cplusplus
58 class Expression;
59 typedef Expression* Expression_ptr;
60 #else
61 typedef void* Expression_ptr;
62 #endif
63 
64 /* Script_section type.  */
65 enum Script_section_type
66 {
67   /* No section type.  */
68   SCRIPT_SECTION_TYPE_NONE,
69   SCRIPT_SECTION_TYPE_NOLOAD,
70   SCRIPT_SECTION_TYPE_DSECT,
71   SCRIPT_SECTION_TYPE_COPY,
72   SCRIPT_SECTION_TYPE_INFO,
73   SCRIPT_SECTION_TYPE_OVERLAY
74 };
75 
76 /* A constraint for whether to use a particular output section
77    definition.  */
78 
79 enum Section_constraint
80 {
81   /* No constraint.  */
82   CONSTRAINT_NONE,
83   /* Only if all input sections are read-only.  */
84   CONSTRAINT_ONLY_IF_RO,
85   /* Only if at least input section is writable.  */
86   CONSTRAINT_ONLY_IF_RW,
87   /* Special constraint.  */
88   CONSTRAINT_SPECIAL
89 };
90 
91 /* The information we store for an output section header in the bison
92    parser.  */
93 
94 struct Parser_output_section_header
95 {
96   /* The address.  This may be NULL.  */
97   Expression_ptr address;
98   /* Section type.  May be NULL string.  */
99   enum Script_section_type section_type;
100   /* The load address, from the AT specifier.  This may be NULL.  */
101   Expression_ptr load_address;
102   /* The alignment, from the ALIGN specifier.  This may be NULL.  */
103   Expression_ptr align;
104   /* The input section alignment, from the SUBALIGN specifier.  This
105      may be NULL.  */
106   Expression_ptr subalign;
107   /* A constraint on this output section.  */
108   enum Section_constraint constraint;
109 };
110 
111 /* We keep vectors of strings.  In order to manage this in both C and
112    C++, we use a pointer to a vector.  This assumes that all pointers
113    look the same.  */
114 
115 #ifdef __cplusplus
116 typedef std::vector<std::string> String_list;
117 typedef String_list* String_list_ptr;
118 #else
119 typedef void* String_list_ptr;
120 #endif
121 
122 /* The information we store for an output section trailer in the bison
123    parser.  */
124 
125 struct Parser_output_section_trailer
126 {
127   /* The fill value.  This may be NULL.  */
128   Expression_ptr fill;
129   /* The program segments this section should go into.  This may be
130      NULL.  */
131   String_list_ptr phdrs;
132 };
133 
134 /* The different sorts we can find in a linker script.  */
135 
136 enum Sort_wildcard
137 {
138   SORT_WILDCARD_NONE,
139   SORT_WILDCARD_BY_NAME,
140   SORT_WILDCARD_BY_ALIGNMENT,
141   SORT_WILDCARD_BY_NAME_BY_ALIGNMENT,
142   SORT_WILDCARD_BY_ALIGNMENT_BY_NAME
143 };
144 
145 /* The information we build for a single wildcard specification.  */
146 
147 struct Wildcard_section
148 {
149   /* The wildcard spec itself.  */
150   struct Parser_string name;
151   /* How the entries should be sorted.  */
152   enum Sort_wildcard sort;
153 };
154 
155 /* A vector of Wildcard_section entries.  */
156 
157 #ifdef __cplusplus
158 typedef std::vector<Wildcard_section> String_sort_list;
159 typedef String_sort_list* String_sort_list_ptr;
160 #else
161 typedef void* String_sort_list_ptr;
162 #endif
163 
164 /* A list of wildcard specifications, which may include EXCLUDE_FILE
165    clauses.  */
166 
167 struct Wildcard_sections
168 {
169   /* Wildcard specs.  */
170   String_sort_list_ptr sections;
171   /* Exclusions.  */
172   String_list_ptr exclude;
173 };
174 
175 /* A complete input section specification.  */
176 
177 struct Input_section_spec
178 {
179   /* The file name.  */
180   struct Wildcard_section file;
181   /* The list of sections.  */
182   struct Wildcard_sections input_sections;
183 };
184 
185 /* Information for a program header.  */
186 
187 struct Phdr_info
188 {
189   /* A boolean value: whether to include the file header.  */
190   int includes_filehdr;
191   /* A boolean value: whether to include the program headers.  */
192   int includes_phdrs;
193   /* A boolean value: whether the flags field is valid.  */
194   int is_flags_valid;
195   /* The value to use for the flags.  */
196   unsigned int flags;
197   /* The load address.  */
198   Expression_ptr load_address;
199 };
200 
201 struct Version_dependency_list;
202 struct Version_expression_list;
203 struct Version_tree;
204 
205 #ifdef __cplusplus
206 extern "C" {
207 #endif
208 
209 /* The bison parser definitions.  */
210 
211 #include "yyscript.h"
212 
213 /* The bison parser function.  */
214 
215 extern int
216 yyparse(void* closure);
217 
218 /* Called by the bison parser skeleton to return the next token.  */
219 
220 extern int
221 yylex(YYSTYPE*, void* closure);
222 
223 /* Called by the bison parser skeleton to report an error.  */
224 
225 extern void
226 yyerror(void* closure, const char*);
227 
228 /* Called by the bison parser to add an external symbol (a symbol in
229    an EXTERN declaration) to the link.  */
230 
231 extern void
232 script_add_extern(void* closure, const char*, size_t);
233 
234 /* Called by the bison parser to add a file to the link.  */
235 
236 extern void
237 script_add_file(void* closure, const char*, size_t);
238 
239 /* Called by the bison parser to add a library to the link.  */
240 
241 extern void
242 script_add_library(void* closure, const char*, size_t);
243 
244 /* Called by the bison parser to start and stop a group.  */
245 
246 extern void
247 script_start_group(void* closure);
248 extern void
249 script_end_group(void* closure);
250 
251 /* Called by the bison parser to start and end an AS_NEEDED list.  */
252 
253 extern void
254 script_start_as_needed(void* closure);
255 extern void
256 script_end_as_needed(void* closure);
257 
258 /* Called by the bison parser to set the entry symbol.  */
259 
260 extern void
261 script_set_entry(void* closure, const char*, size_t);
262 
263 /* Called by the bison parser to set whether to define common symbols.  */
264 
265 extern void
266 script_set_common_allocation(void* closure, int);
267 
268 /* Called by the bison parser to parse an OPTION.  */
269 
270 extern void
271 script_parse_option(void* closure, const char*, size_t);
272 
273 /* Called by the bison parser to handle OUTPUT_FORMAT.  This return 0
274    if the parse should be aborted.  */
275 
276 extern int
277 script_check_output_format(void* closure, const char*, size_t,
278 			   const char*, size_t, const char*, size_t);
279 
280 /* Called by the bison parser to handle TARGET.  */
281 extern void
282 script_set_target(void* closure, const char*, size_t);
283 
284 /* Called by the bison parser to handle SEARCH_DIR.  */
285 
286 extern void
287 script_add_search_dir(void* closure, const char*, size_t);
288 
289 /* Called by the bison parser to push the lexer into expression
290    mode.  */
291 
292 extern void
293 script_push_lex_into_expression_mode(void* closure);
294 
295 /* Called by the bison parser to push the lexer into version
296    mode.  */
297 
298 extern void
299 script_push_lex_into_version_mode(void* closure);
300 
301 /* Called by the bison parser to pop the lexer mode.  */
302 
303 extern void
304 script_pop_lex_mode(void* closure);
305 
306 /* Called by the bison parser to get the value of a symbol.  This is
307    called for a reference to a symbol, but is not called for something
308    like "sym += 10".  Uses of the special symbol "." can just call
309    script_exp_string.  */
310 
311 extern Expression_ptr
312 script_symbol(void* closure, const char*, size_t);
313 
314 /* Called by the bison parser to set a symbol to a value.  PROVIDE is
315    non-zero if the symbol should be provided--only defined if there is
316    an undefined reference.  HIDDEN is non-zero if the symbol should be
317    hidden.  */
318 
319 extern void
320 script_set_symbol(void* closure, const char*, size_t, Expression_ptr,
321 		  int provide, int hidden);
322 
323 /* Called by the bison parser to add an assertion.  */
324 
325 extern void
326 script_add_assertion(void* closure, Expression_ptr, const char* message,
327 		     size_t messagelen);
328 
329 /* Called by the bison parser to start a SECTIONS clause.  */
330 
331 extern void
332 script_start_sections(void* closure);
333 
334 /* Called by the bison parser to finish a SECTIONS clause.  */
335 
336 extern void
337 script_finish_sections(void* closure);
338 
339 /* Called by the bison parser to start handling input section
340    specifications for an output section.  */
341 
342 extern void
343 script_start_output_section(void* closure, const char* name, size_t namelen,
344 			    const struct Parser_output_section_header*);
345 
346 /* Called by the bison parser when done handling input section
347    specifications for an output section.  */
348 
349 extern void
350 script_finish_output_section(void* closure,
351 			     const struct Parser_output_section_trailer*);
352 
353 /* Called by the bison parser to handle a data statement (LONG, BYTE,
354    etc.) in an output section.  */
355 
356 extern void
357 script_add_data(void* closure, int data_token, Expression_ptr val);
358 
359 /* Called by the bison parser to set the fill value in an output
360    section.  */
361 
362 extern void
363 script_add_fill(void* closure, Expression_ptr val);
364 
365 /* Called by the bison parser to add an input section specification to
366    an output section.  The KEEP parameter is non-zero if this is
367    within a KEEP clause, meaning that the garbage collector should not
368    discard it.  */
369 
370 extern void
371 script_add_input_section(void* closure, const struct Input_section_spec*,
372 			 int keep);
373 
374 /* Create a new list of string and sort entries.  */
375 
376 extern String_sort_list_ptr
377 script_new_string_sort_list(const struct Wildcard_section*);
378 
379 /* Add an entry to a list of string and sort entries.  */
380 
381 extern String_sort_list_ptr
382 script_string_sort_list_add(String_sort_list_ptr,
383 			    const struct Wildcard_section*);
384 
385 /* Create a new list of strings.  */
386 
387 extern String_list_ptr
388 script_new_string_list(const char*, size_t);
389 
390 /* Add an element to a list of strings.  */
391 
392 extern String_list_ptr
393 script_string_list_push_back(String_list_ptr, const char*, size_t);
394 
395 /* Concatenate two string lists.  */
396 
397 extern String_list_ptr
398 script_string_list_append(String_list_ptr, String_list_ptr);
399 
400 /* Define a new program header.  */
401 
402 extern void
403 script_add_phdr(void* closure, const char* name, size_t namelen,
404 		unsigned int type, const struct Phdr_info*);
405 
406 /* Convert a program header string to a type.  */
407 
408 extern unsigned int
409 script_phdr_string_to_type(void* closure, const char*, size_t);
410 
411 /* Handle DATA_SEGMENT_ALIGN and DATA_SEGMENT_RELRO_END.  */
412 
413 extern void
414 script_data_segment_align(void* closure);
415 
416 extern void
417 script_data_segment_relro_end(void* closure);
418 
419 /* Record the fact that a SEGMENT_START expression is seen.  */
420 
421 extern void
422 script_saw_segment_start_expression(void* closure);
423 
424 /* Called by the bison parser for MEMORY regions.  */
425 
426 extern void
427 script_add_memory(void*, const char*, size_t, unsigned int,
428 		  Expression_ptr, Expression_ptr);
429 
430 extern unsigned int
431 script_parse_memory_attr(void*, const char*, size_t, int);
432 
433 extern void
434 script_set_section_region(void*, const char*, size_t, int);
435 
436 extern void
437 script_include_directive(int, void *, const char*, size_t);
438 
439 /* Called by the bison parser for expressions.  */
440 
441 extern Expression_ptr
442 script_exp_unary_minus(Expression_ptr);
443 extern Expression_ptr
444 script_exp_unary_logical_not(Expression_ptr);
445 extern Expression_ptr
446 script_exp_unary_bitwise_not(Expression_ptr);
447 extern Expression_ptr
448 script_exp_binary_mult(Expression_ptr, Expression_ptr);
449 extern Expression_ptr
450 script_exp_binary_div(Expression_ptr, Expression_ptr);
451 extern Expression_ptr
452 script_exp_binary_mod(Expression_ptr, Expression_ptr);
453 extern Expression_ptr
454 script_exp_binary_add(Expression_ptr, Expression_ptr);
455 extern Expression_ptr
456 script_exp_binary_sub(Expression_ptr, Expression_ptr);
457 extern Expression_ptr
458 script_exp_binary_lshift(Expression_ptr, Expression_ptr);
459 extern Expression_ptr
460 script_exp_binary_rshift(Expression_ptr, Expression_ptr);
461 extern Expression_ptr
462 script_exp_binary_eq(Expression_ptr, Expression_ptr);
463 extern Expression_ptr
464 script_exp_binary_ne(Expression_ptr, Expression_ptr);
465 extern Expression_ptr
466 script_exp_binary_le(Expression_ptr, Expression_ptr);
467 extern Expression_ptr
468 script_exp_binary_ge(Expression_ptr, Expression_ptr);
469 extern Expression_ptr
470 script_exp_binary_lt(Expression_ptr, Expression_ptr);
471 extern Expression_ptr
472 script_exp_binary_gt(Expression_ptr, Expression_ptr);
473 extern Expression_ptr
474 script_exp_binary_bitwise_and(Expression_ptr, Expression_ptr);
475 extern Expression_ptr
476 script_exp_binary_bitwise_xor(Expression_ptr, Expression_ptr);
477 extern Expression_ptr
478 script_exp_binary_bitwise_or(Expression_ptr, Expression_ptr);
479 extern Expression_ptr
480 script_exp_binary_logical_and(Expression_ptr, Expression_ptr);
481 extern Expression_ptr
482 script_exp_binary_logical_or(Expression_ptr, Expression_ptr);
483 extern Expression_ptr
484 script_exp_trinary_cond(Expression_ptr, Expression_ptr, Expression_ptr);
485 extern Expression_ptr
486 script_exp_integer(uint64_t);
487 extern Expression_ptr
488 script_exp_string(const char*, size_t);
489 extern Expression_ptr
490 script_exp_function_max(Expression_ptr, Expression_ptr);
491 extern Expression_ptr
492 script_exp_function_min(Expression_ptr, Expression_ptr);
493 extern Expression_ptr
494 script_exp_function_defined(const char*, size_t);
495 extern Expression_ptr
496 script_exp_function_sizeof_headers(void);
497 extern Expression_ptr
498 script_exp_function_alignof(const char*, size_t);
499 extern Expression_ptr
500 script_exp_function_sizeof(const char*, size_t);
501 extern Expression_ptr
502 script_exp_function_addr(const char*, size_t);
503 extern Expression_ptr
504 script_exp_function_loadaddr(const char*, size_t);
505 extern Expression_ptr
506 script_exp_function_origin(void*, const char*, size_t);
507 extern Expression_ptr
508 script_exp_function_length(void*, const char*, size_t);
509 extern Expression_ptr
510 script_exp_function_constant(const char*, size_t);
511 extern Expression_ptr
512 script_exp_function_absolute(Expression_ptr);
513 extern Expression_ptr
514 script_exp_function_align(Expression_ptr, Expression_ptr);
515 extern Expression_ptr
516 script_exp_function_data_segment_align(Expression_ptr, Expression_ptr);
517 extern Expression_ptr
518 script_exp_function_data_segment_relro_end(Expression_ptr, Expression_ptr);
519 extern Expression_ptr
520 script_exp_function_data_segment_end(Expression_ptr);
521 extern Expression_ptr
522 script_exp_function_segment_start(const char*, size_t, Expression_ptr);
523 extern Expression_ptr
524 script_exp_function_assert(Expression_ptr, const char*, size_t);
525 
526 extern void
527 script_register_vers_node(void* closure,
528 			  const char* tag,
529 			  int taglen,
530 			  struct Version_tree*,
531 			  struct Version_dependency_list*);
532 
533 extern struct Version_dependency_list*
534 script_add_vers_depend(void* closure,
535 		       struct Version_dependency_list* existing_dependencies,
536 		       const char* depend_to_add, int deplen);
537 
538 extern struct Version_expression_list*
539 script_new_vers_pattern(void* closure,
540 			struct Version_expression_list*,
541 			const char*, int, int);
542 
543 extern struct Version_expression_list*
544 script_merge_expressions(struct Version_expression_list* a,
545                          struct Version_expression_list* b);
546 
547 extern struct Version_tree*
548 script_new_vers_node(void* closure,
549 		     struct Version_expression_list* global,
550 		     struct Version_expression_list* local);
551 
552 extern void
553 version_script_push_lang(void* closure, const char* lang, int langlen);
554 
555 extern void
556 version_script_pop_lang(void* closure);
557 
558 #ifdef __cplusplus
559 } // End extern "C"
560 #endif
561 
562 #ifdef __cplusplus
563 } // End namespace gold.
564 #endif
565 
566 #endif /* !defined(GOLD_SCRIPT_C_H) */
567