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6dddc817 DE |
1 | /* Interface between gdb and its extension languages. |
2 | ||
4f8fcb74 | 3 | Copyright (C) 2014 Free Software Foundation, Inc. |
6dddc817 DE |
4 | |
5 | This file is part of GDB. | |
6 | ||
7 | This program is free software; you can redistribute it and/or modify | |
8 | it under the terms of the GNU General Public License as published by | |
9 | the Free Software Foundation; either version 3 of the License, or | |
10 | (at your option) any later version. | |
11 | ||
12 | This program is distributed in the hope that it will be useful, | |
13 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
14 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
15 | GNU General Public License for more details. | |
16 | ||
17 | You should have received a copy of the GNU General Public License | |
18 | along with this program. If not, see <http://www.gnu.org/licenses/>. */ | |
19 | ||
20 | /* Note: With few exceptions, external functions and variables in this file | |
21 | have "ext_lang" in the name, and no other symbol in gdb does. */ | |
22 | ||
23 | #include "defs.h" | |
24 | #include <signal.h> | |
25 | #include "auto-load.h" | |
26 | #include "breakpoint.h" | |
27 | #include "event-top.h" | |
28 | #include "extension.h" | |
29 | #include "extension-priv.h" | |
30 | #include "observer.h" | |
31 | #include "cli/cli-script.h" | |
32 | #include "python/python.h" | |
ed3ef339 | 33 | #include "guile/guile.h" |
6dddc817 DE |
34 | |
35 | /* Iterate over all external extension languages, regardless of whether the | |
36 | support has been compiled in or not. | |
37 | This does not include GDB's own scripting language. */ | |
38 | ||
39 | #define ALL_EXTENSION_LANGUAGES(i, extlang) \ | |
40 | for (/*int*/ i = 0, extlang = extension_languages[0]; \ | |
41 | extlang != NULL; \ | |
42 | extlang = extension_languages[++i]) | |
43 | ||
44 | /* Iterate over all external extension languages that are supported. | |
45 | This does not include GDB's own scripting language. */ | |
46 | ||
47 | #define ALL_ENABLED_EXTENSION_LANGUAGES(i, extlang) \ | |
48 | for (/*int*/ i = 0, extlang = extension_languages[0]; \ | |
49 | extlang != NULL; \ | |
50 | extlang = extension_languages[++i]) \ | |
51 | if (extlang->ops != NULL) | |
52 | ||
53 | static script_sourcer_func source_gdb_script; | |
54 | static objfile_script_sourcer_func source_gdb_objfile_script; | |
55 | ||
56 | /* GDB's own scripting language. | |
57 | This exists, in part, to support auto-loading ${prog}-gdb.gdb scripts. */ | |
58 | ||
59 | static const struct extension_language_script_ops | |
60 | extension_language_gdb_script_ops = | |
61 | { | |
62 | source_gdb_script, | |
63 | source_gdb_objfile_script, | |
64 | auto_load_gdb_scripts_enabled | |
65 | }; | |
66 | ||
67 | const struct extension_language_defn extension_language_gdb = | |
68 | { | |
69 | EXT_LANG_GDB, | |
70 | "gdb", | |
71 | "GDB", | |
72 | ||
73 | /* We fall back to interpreting a script as a GDB script if it doesn't | |
74 | match the other scripting languages, but for consistency's sake | |
75 | give it a formal suffix. */ | |
76 | ".gdb", | |
77 | "-gdb.gdb", | |
78 | ||
79 | /* cli_control_type: This is never used: GDB's own scripting language | |
80 | has a variety of control types (if, while, etc.). */ | |
81 | commands_control, | |
82 | ||
83 | &extension_language_gdb_script_ops, | |
84 | ||
85 | /* The rest of the extension language interface isn't supported by GDB's own | |
86 | extension/scripting language. */ | |
87 | NULL | |
88 | }; | |
89 | ||
90 | /* NULL-terminated table of all external (non-native) extension languages. | |
91 | ||
92 | The order of appearance in the table is important. | |
93 | When multiple extension languages provide the same feature, for example | |
94 | a pretty-printer for a particular type, which one gets used? | |
95 | The algorithm employed here is "the first one wins". For example, in | |
96 | the case of pretty-printers this means the first one to provide a | |
97 | pretty-printed value is the one that is used. This algorithm is employed | |
98 | throughout. */ | |
99 | ||
100 | static const struct extension_language_defn * const extension_languages[] = | |
101 | { | |
102 | /* To preserve existing behaviour, python should always appear first. */ | |
103 | &extension_language_python, | |
ed3ef339 | 104 | &extension_language_guile, |
6dddc817 DE |
105 | NULL |
106 | }; | |
107 | ||
108 | /* Return a pointer to the struct extension_language_defn object of | |
109 | extension language LANG. | |
110 | This always returns a non-NULL pointer, even if support for the language | |
111 | is not compiled into this copy of GDB. */ | |
112 | ||
113 | const struct extension_language_defn * | |
114 | get_ext_lang_defn (enum extension_language lang) | |
115 | { | |
116 | int i; | |
117 | const struct extension_language_defn *extlang; | |
118 | ||
119 | gdb_assert (lang != EXT_LANG_NONE); | |
120 | ||
121 | if (lang == EXT_LANG_GDB) | |
122 | return &extension_language_gdb; | |
123 | ||
124 | ALL_EXTENSION_LANGUAGES (i, extlang) | |
125 | { | |
126 | if (extlang->language == lang) | |
127 | return extlang; | |
128 | } | |
129 | ||
130 | gdb_assert_not_reached ("unable to find extension_language_defn"); | |
131 | } | |
132 | ||
133 | /* Return TRUE if FILE has extension EXTENSION. */ | |
134 | ||
135 | static int | |
136 | has_extension (const char *file, const char *extension) | |
137 | { | |
138 | int file_len = strlen (file); | |
139 | int extension_len = strlen (extension); | |
140 | ||
141 | return (file_len > extension_len | |
142 | && strcmp (&file[file_len - extension_len], extension) == 0); | |
143 | } | |
144 | ||
145 | /* Return the extension language of FILE, or NULL if | |
146 | the extension language of FILE is not recognized. | |
147 | This is done by looking at the file's suffix. */ | |
148 | ||
149 | const struct extension_language_defn * | |
150 | get_ext_lang_of_file (const char *file) | |
151 | { | |
152 | int i; | |
153 | const struct extension_language_defn *extlang; | |
154 | ||
155 | ALL_EXTENSION_LANGUAGES (i, extlang) | |
156 | { | |
157 | if (has_extension (file, extlang->suffix)) | |
158 | return extlang; | |
159 | } | |
160 | ||
161 | return NULL; | |
162 | } | |
163 | ||
164 | /* Return non-zero if support for the specified extension language | |
165 | is compiled in. */ | |
166 | ||
167 | int | |
168 | ext_lang_present_p (const struct extension_language_defn *extlang) | |
169 | { | |
170 | return extlang->script_ops != NULL; | |
171 | } | |
172 | ||
173 | /* Return non-zero if the specified extension language has successfully | |
174 | initialized. */ | |
175 | ||
176 | int | |
177 | ext_lang_initialized_p (const struct extension_language_defn *extlang) | |
178 | { | |
179 | if (extlang->ops != NULL) | |
180 | { | |
181 | /* This method is required. */ | |
182 | gdb_assert (extlang->ops->initialized != NULL); | |
183 | return extlang->ops->initialized (extlang); | |
184 | } | |
185 | ||
186 | return 0; | |
187 | } | |
188 | ||
189 | /* Throw an error indicating EXTLANG is not supported in this copy of GDB. */ | |
190 | ||
191 | void | |
192 | throw_ext_lang_unsupported (const struct extension_language_defn *extlang) | |
193 | { | |
194 | error (_("Scripting in the \"%s\" language is not supported" | |
195 | " in this copy of GDB."), | |
196 | ext_lang_capitalized_name (extlang)); | |
197 | } | |
198 | \f | |
199 | /* Methods for GDB's own extension/scripting language. */ | |
200 | ||
201 | /* The extension_language_script_ops.script_sourcer "method". */ | |
202 | ||
203 | static void | |
204 | source_gdb_script (const struct extension_language_defn *extlang, | |
205 | FILE *stream, const char *file) | |
206 | { | |
207 | script_from_file (stream, file); | |
208 | } | |
209 | ||
210 | /* The extension_language_script_ops.objfile_script_sourcer "method". */ | |
211 | ||
212 | static void | |
213 | source_gdb_objfile_script (const struct extension_language_defn *extlang, | |
214 | struct objfile *objfile, | |
215 | FILE *stream, const char *file) | |
216 | { | |
217 | script_from_file (stream, file); | |
218 | } | |
219 | \f | |
220 | /* Accessors for "public" attributes of struct extension_language. */ | |
221 | ||
222 | /* Return the "name" field of EXTLANG. */ | |
223 | ||
224 | const char * | |
225 | ext_lang_name (const struct extension_language_defn *extlang) | |
226 | { | |
227 | return extlang->name; | |
228 | } | |
229 | ||
230 | /* Return the "capitalized_name" field of EXTLANG. */ | |
231 | ||
232 | const char * | |
233 | ext_lang_capitalized_name (const struct extension_language_defn *extlang) | |
234 | { | |
235 | return extlang->capitalized_name; | |
236 | } | |
237 | ||
238 | /* Return the "suffix" field of EXTLANG. */ | |
239 | ||
240 | const char * | |
241 | ext_lang_suffix (const struct extension_language_defn *extlang) | |
242 | { | |
243 | return extlang->suffix; | |
244 | } | |
245 | ||
246 | /* Return the "auto_load_suffix" field of EXTLANG. */ | |
247 | ||
248 | const char * | |
249 | ext_lang_auto_load_suffix (const struct extension_language_defn *extlang) | |
250 | { | |
251 | return extlang->auto_load_suffix; | |
252 | } | |
253 | \f | |
254 | /* extension_language_script_ops wrappers. */ | |
255 | ||
256 | /* Return the script "sourcer" function for EXTLANG. | |
257 | This is the function that loads and processes a script. | |
258 | If support for this language isn't compiled in, NULL is returned. */ | |
259 | ||
260 | script_sourcer_func * | |
261 | ext_lang_script_sourcer (const struct extension_language_defn *extlang) | |
262 | { | |
263 | if (extlang->script_ops == NULL) | |
264 | return NULL; | |
265 | ||
266 | /* The extension language is required to implement this function. */ | |
267 | gdb_assert (extlang->script_ops->script_sourcer != NULL); | |
268 | ||
269 | return extlang->script_ops->script_sourcer; | |
270 | } | |
271 | ||
272 | /* Return the objfile script "sourcer" function for EXTLANG. | |
273 | This is the function that loads and processes a script for a particular | |
274 | objfile. | |
275 | If support for this language isn't compiled in, NULL is returned. */ | |
276 | ||
277 | objfile_script_sourcer_func * | |
278 | ext_lang_objfile_script_sourcer (const struct extension_language_defn *extlang) | |
279 | { | |
280 | if (extlang->script_ops == NULL) | |
281 | return NULL; | |
282 | ||
283 | /* The extension language is required to implement this function. */ | |
284 | gdb_assert (extlang->script_ops->objfile_script_sourcer != NULL); | |
285 | ||
286 | return extlang->script_ops->objfile_script_sourcer; | |
287 | } | |
288 | ||
289 | /* Return non-zero if auto-loading of EXTLANG scripts is enabled. | |
290 | Zero is returned if support for this language isn't compiled in. */ | |
291 | ||
292 | int | |
293 | ext_lang_auto_load_enabled (const struct extension_language_defn *extlang) | |
294 | { | |
295 | if (extlang->script_ops == NULL) | |
296 | return 0; | |
297 | ||
298 | /* The extension language is required to implement this function. */ | |
299 | gdb_assert (extlang->script_ops->auto_load_enabled != NULL); | |
300 | ||
301 | return extlang->script_ops->auto_load_enabled (extlang); | |
302 | } | |
303 | \f | |
304 | /* Functions that iterate over all extension languages. | |
305 | These only iterate over external extension languages, not including | |
306 | GDB's own extension/scripting language, unless otherwise indicated. */ | |
307 | ||
308 | /* Wrapper to call the extension_language_ops.finish_initialization "method" | |
309 | for each compiled-in extension language. */ | |
310 | ||
311 | void | |
312 | finish_ext_lang_initialization (void) | |
313 | { | |
314 | int i; | |
315 | const struct extension_language_defn *extlang; | |
316 | ||
317 | ALL_ENABLED_EXTENSION_LANGUAGES (i, extlang) | |
318 | { | |
319 | if (extlang->ops->finish_initialization != NULL) | |
320 | extlang->ops->finish_initialization (extlang); | |
321 | } | |
322 | } | |
323 | ||
324 | /* Invoke the appropriate extension_language_ops.eval_from_control_command | |
325 | method to perform CMD, which is a list of commands in an extension language. | |
326 | ||
327 | This function is what implements, for example: | |
328 | ||
329 | python | |
330 | print 42 | |
331 | end | |
332 | ||
333 | in a GDB script. */ | |
334 | ||
335 | void | |
336 | eval_ext_lang_from_control_command (struct command_line *cmd) | |
337 | { | |
338 | int i; | |
339 | const struct extension_language_defn *extlang; | |
340 | ||
341 | ALL_EXTENSION_LANGUAGES (i, extlang) | |
342 | { | |
343 | if (extlang->cli_control_type == cmd->control_type) | |
344 | { | |
feef67ab DE |
345 | if (extlang->ops != NULL |
346 | && extlang->ops->eval_from_control_command != NULL) | |
6dddc817 DE |
347 | { |
348 | extlang->ops->eval_from_control_command (extlang, cmd); | |
349 | return; | |
350 | } | |
351 | /* The requested extension language is not supported in this GDB. */ | |
352 | throw_ext_lang_unsupported (extlang); | |
353 | } | |
354 | } | |
355 | ||
356 | gdb_assert_not_reached ("unknown extension language in command_line"); | |
357 | } | |
358 | ||
359 | /* Search for and load scripts for OBJFILE written in extension languages. | |
360 | This includes GDB's own scripting language. | |
361 | ||
362 | This function is what implements the loading of OBJFILE-gdb.py and | |
363 | OBJFILE-gdb.gdb. */ | |
364 | ||
365 | void | |
366 | auto_load_ext_lang_scripts_for_objfile (struct objfile *objfile) | |
367 | { | |
368 | int i; | |
369 | const struct extension_language_defn *extlang; | |
370 | ||
371 | extlang = &extension_language_gdb; | |
372 | if (ext_lang_auto_load_enabled (extlang)) | |
373 | auto_load_objfile_script (objfile, extlang); | |
374 | ||
375 | ALL_ENABLED_EXTENSION_LANGUAGES (i, extlang) | |
376 | { | |
377 | if (ext_lang_auto_load_enabled (extlang)) | |
378 | auto_load_objfile_script (objfile, extlang); | |
379 | } | |
380 | } | |
381 | \f | |
382 | /* Interface to type pretty-printers implemented in an extension language. */ | |
383 | ||
384 | /* Call this at the start when preparing to pretty-print a type. | |
385 | The result is a pointer to an opaque object (to the caller) to be passed | |
386 | to apply_ext_lang_type_printers and free_ext_lang_type_printers. | |
387 | ||
388 | We don't know in advance which extension language will provide a | |
389 | pretty-printer for the type, so all are initialized. */ | |
390 | ||
391 | struct ext_lang_type_printers * | |
392 | start_ext_lang_type_printers (void) | |
393 | { | |
394 | struct ext_lang_type_printers *printers | |
395 | = XCNEW (struct ext_lang_type_printers); | |
396 | int i; | |
397 | const struct extension_language_defn *extlang; | |
398 | ||
399 | ALL_ENABLED_EXTENSION_LANGUAGES (i, extlang) | |
400 | { | |
401 | if (extlang->ops->start_type_printers != NULL) | |
402 | extlang->ops->start_type_printers (extlang, printers); | |
403 | } | |
404 | ||
405 | return printers; | |
406 | } | |
407 | ||
408 | /* Iteratively try the type pretty-printers specified by PRINTERS | |
409 | according to the standard search order (specified by extension_languages), | |
410 | returning the result of the first one that succeeds. | |
411 | If there was an error, or if no printer succeeds, then NULL is returned. */ | |
412 | ||
413 | char * | |
414 | apply_ext_lang_type_printers (struct ext_lang_type_printers *printers, | |
415 | struct type *type) | |
416 | { | |
417 | int i; | |
418 | const struct extension_language_defn *extlang; | |
419 | ||
420 | ALL_ENABLED_EXTENSION_LANGUAGES (i, extlang) | |
421 | { | |
422 | char *result = NULL; | |
423 | enum ext_lang_rc rc; | |
424 | ||
425 | if (extlang->ops->apply_type_printers == NULL) | |
426 | continue; | |
427 | rc = extlang->ops->apply_type_printers (extlang, printers, type, | |
428 | &result); | |
429 | switch (rc) | |
430 | { | |
431 | case EXT_LANG_RC_OK: | |
432 | gdb_assert (result != NULL); | |
433 | return result; | |
434 | case EXT_LANG_RC_ERROR: | |
435 | return NULL; | |
436 | case EXT_LANG_RC_NOP: | |
437 | break; | |
438 | default: | |
439 | gdb_assert_not_reached ("bad return from apply_type_printers"); | |
440 | } | |
441 | } | |
442 | ||
443 | return NULL; | |
444 | } | |
445 | ||
446 | /* Call this after pretty-printing a type to release all memory held | |
447 | by PRINTERS. */ | |
448 | ||
449 | void | |
450 | free_ext_lang_type_printers (struct ext_lang_type_printers *printers) | |
451 | { | |
452 | int i; | |
453 | const struct extension_language_defn *extlang; | |
454 | ||
455 | ALL_ENABLED_EXTENSION_LANGUAGES (i, extlang) | |
456 | { | |
457 | if (extlang->ops->free_type_printers != NULL) | |
458 | extlang->ops->free_type_printers (extlang, printers); | |
459 | } | |
460 | ||
461 | xfree (printers); | |
462 | } | |
463 | \f | |
464 | /* Try to pretty-print a value of type TYPE located at VALADDR | |
465 | + EMBEDDED_OFFSET, which came from the inferior at address ADDRESS | |
466 | + EMBEDDED_OFFSET, onto stdio stream STREAM according to OPTIONS. | |
467 | VAL is the whole object that came from ADDRESS. VALADDR must point to | |
468 | the head of VAL's contents buffer. | |
469 | Returns non-zero if the value was successfully pretty-printed. | |
470 | ||
471 | Extension languages are tried in the order specified by | |
472 | extension_languages. The first one to provide a pretty-printed | |
473 | value "wins". | |
474 | ||
475 | If an error is encountered in a pretty-printer, no further extension | |
476 | languages are tried. | |
477 | Note: This is different than encountering a memory error trying to read a | |
478 | value for pretty-printing. Here we're referring to, e.g., programming | |
479 | errors that trigger an exception in the extension language. */ | |
480 | ||
481 | int | |
482 | apply_ext_lang_val_pretty_printer (struct type *type, const gdb_byte *valaddr, | |
483 | int embedded_offset, CORE_ADDR address, | |
484 | struct ui_file *stream, int recurse, | |
485 | const struct value *val, | |
486 | const struct value_print_options *options, | |
487 | const struct language_defn *language) | |
488 | { | |
489 | int i; | |
490 | const struct extension_language_defn *extlang; | |
491 | ||
492 | ALL_ENABLED_EXTENSION_LANGUAGES (i, extlang) | |
493 | { | |
494 | enum ext_lang_rc rc; | |
495 | ||
496 | if (extlang->ops->apply_val_pretty_printer == NULL) | |
497 | continue; | |
498 | rc = extlang->ops->apply_val_pretty_printer (extlang, type, valaddr, | |
499 | embedded_offset, address, | |
500 | stream, recurse, val, | |
501 | options, language); | |
502 | switch (rc) | |
503 | { | |
504 | case EXT_LANG_RC_OK: | |
505 | return 1; | |
506 | case EXT_LANG_RC_ERROR: | |
507 | return 0; | |
508 | case EXT_LANG_RC_NOP: | |
509 | break; | |
510 | default: | |
511 | gdb_assert_not_reached ("bad return from apply_val_pretty_printer"); | |
512 | } | |
513 | } | |
514 | ||
515 | return 0; | |
516 | } | |
517 | ||
518 | /* GDB access to the "frame filter" feature. | |
519 | FRAME is the source frame to start frame-filter invocation. FLAGS is an | |
520 | integer holding the flags for printing. The following elements of | |
521 | the FRAME_FILTER_FLAGS enum denotes the make-up of FLAGS: | |
522 | PRINT_LEVEL is a flag indicating whether to print the frame's | |
523 | relative level in the output. PRINT_FRAME_INFO is a flag that | |
524 | indicates whether this function should print the frame | |
525 | information, PRINT_ARGS is a flag that indicates whether to print | |
526 | frame arguments, and PRINT_LOCALS, likewise, with frame local | |
527 | variables. ARGS_TYPE is an enumerator describing the argument | |
528 | format, OUT is the output stream to print. FRAME_LOW is the | |
529 | beginning of the slice of frames to print, and FRAME_HIGH is the | |
530 | upper limit of the frames to count. Returns EXT_LANG_BT_ERROR on error, | |
531 | or EXT_LANG_BT_COMPLETED on success. | |
532 | ||
533 | Extension languages are tried in the order specified by | |
534 | extension_languages. The first one to provide a filter "wins". | |
535 | If there is an error (EXT_LANG_BT_ERROR) it is reported immediately | |
536 | rather than trying filters in other extension languages. */ | |
537 | ||
538 | enum ext_lang_bt_status | |
539 | apply_ext_lang_frame_filter (struct frame_info *frame, int flags, | |
540 | enum ext_lang_frame_args args_type, | |
541 | struct ui_out *out, | |
542 | int frame_low, int frame_high) | |
543 | { | |
544 | int i; | |
545 | const struct extension_language_defn *extlang; | |
546 | ||
547 | ALL_ENABLED_EXTENSION_LANGUAGES (i, extlang) | |
548 | { | |
549 | enum ext_lang_bt_status status; | |
550 | ||
551 | if (extlang->ops->apply_frame_filter == NULL) | |
552 | continue; | |
553 | status = extlang->ops->apply_frame_filter (extlang, frame, flags, | |
554 | args_type, out, | |
555 | frame_low, frame_high); | |
556 | /* We use the filters from the first extension language that has | |
557 | applicable filters. Also, an error is reported immediately | |
558 | rather than continue trying. */ | |
559 | if (status != EXT_LANG_BT_NO_FILTERS) | |
560 | return status; | |
561 | } | |
562 | ||
563 | return EXT_LANG_BT_NO_FILTERS; | |
564 | } | |
565 | ||
566 | /* Update values held by the extension language when OBJFILE is discarded. | |
567 | New global types must be created for every such value, which must then be | |
568 | updated to use the new types. | |
569 | The function typically just iterates over all appropriate values and | |
570 | calls preserve_one_value for each one. | |
571 | COPIED_TYPES is used to prevent cycles / duplicates and is passed to | |
572 | preserve_one_value. */ | |
573 | ||
574 | void | |
575 | preserve_ext_lang_values (struct objfile *objfile, htab_t copied_types) | |
576 | { | |
577 | int i; | |
578 | const struct extension_language_defn *extlang; | |
579 | ||
580 | ALL_ENABLED_EXTENSION_LANGUAGES (i, extlang) | |
581 | { | |
582 | if (extlang->ops->preserve_values != NULL) | |
583 | extlang->ops->preserve_values (extlang, objfile, copied_types); | |
584 | } | |
585 | } | |
586 | ||
587 | /* If there is a stop condition implemented in an extension language for | |
588 | breakpoint B, return a pointer to the extension language's definition. | |
589 | Otherwise return NULL. | |
590 | If SKIP_LANG is not EXT_LANG_NONE, skip checking this language. | |
591 | This is for the case where we're setting a new condition: Only one | |
592 | condition is allowed, so when setting a condition for any particular | |
593 | extension language, we need to check if any other extension language | |
594 | already has a condition set. */ | |
595 | ||
596 | const struct extension_language_defn * | |
597 | get_breakpoint_cond_ext_lang (struct breakpoint *b, | |
598 | enum extension_language skip_lang) | |
599 | { | |
600 | int i; | |
601 | const struct extension_language_defn *extlang; | |
602 | ||
603 | ALL_ENABLED_EXTENSION_LANGUAGES (i, extlang) | |
604 | { | |
605 | if (extlang->language != skip_lang | |
606 | && extlang->ops->breakpoint_has_cond != NULL | |
607 | && extlang->ops->breakpoint_has_cond (extlang, b)) | |
608 | return extlang; | |
609 | } | |
610 | ||
611 | return NULL; | |
612 | } | |
613 | ||
614 | /* Return whether a stop condition for breakpoint B says to stop. | |
615 | True is also returned if there is no stop condition for B. */ | |
616 | ||
617 | int | |
618 | breakpoint_ext_lang_cond_says_stop (struct breakpoint *b) | |
619 | { | |
620 | int i; | |
621 | const struct extension_language_defn *extlang; | |
622 | enum ext_lang_bp_stop stop = EXT_LANG_BP_STOP_UNSET; | |
623 | ||
624 | ALL_ENABLED_EXTENSION_LANGUAGES (i, extlang) | |
625 | { | |
626 | /* There is a rule that a breakpoint can have at most one of any of a | |
627 | CLI or extension language condition. However, Python hacks in "finish | |
628 | breakpoints" on top of the "stop" check, so we have to call this for | |
629 | every language, even if we could first determine whether a "stop" | |
630 | method exists. */ | |
631 | if (extlang->ops->breakpoint_cond_says_stop != NULL) | |
632 | { | |
633 | enum ext_lang_bp_stop this_stop | |
634 | = extlang->ops->breakpoint_cond_says_stop (extlang, b); | |
635 | ||
636 | if (this_stop != EXT_LANG_BP_STOP_UNSET) | |
637 | { | |
638 | /* Even though we have to check every extension language, only | |
639 | one of them can return yes/no (because only one of them | |
640 | can have a "stop" condition). */ | |
641 | gdb_assert (stop == EXT_LANG_BP_STOP_UNSET); | |
642 | stop = this_stop; | |
643 | } | |
644 | } | |
645 | } | |
646 | ||
647 | return stop == EXT_LANG_BP_STOP_NO ? 0 : 1; | |
648 | } | |
649 | \f | |
650 | /* ^C/SIGINT support. | |
651 | This requires cooperation with the extension languages so the support | |
652 | is defined here. */ | |
653 | ||
654 | /* This flag tracks quit requests when we haven't called out to an | |
655 | extension language. it also holds quit requests when we transition to | |
656 | an extension language that doesn't have cooperative SIGINT handling. */ | |
657 | static int quit_flag; | |
658 | ||
659 | /* The current extension language we've called out to, or | |
660 | extension_language_gdb if there isn't one. | |
661 | This must be set everytime we call out to an extension language, and reset | |
662 | to the previous value when it returns. Note that the previous value may | |
663 | be a different (or the same) extension language. */ | |
664 | static const struct extension_language_defn *active_ext_lang | |
665 | = &extension_language_gdb; | |
666 | ||
667 | /* Return the currently active extension language. */ | |
668 | ||
669 | const struct extension_language_defn * | |
670 | get_active_ext_lang (void) | |
671 | { | |
672 | return active_ext_lang; | |
673 | } | |
674 | ||
675 | /* Install a SIGINT handler. */ | |
676 | ||
677 | static void | |
678 | install_sigint_handler (const struct signal_handler *handler_state) | |
679 | { | |
680 | gdb_assert (handler_state->handler_saved); | |
681 | ||
682 | signal (SIGINT, handler_state->handler); | |
683 | } | |
684 | ||
685 | /* Install GDB's SIGINT handler, storing the previous version in *PREVIOUS. | |
686 | As a simple optimization, if the previous version was GDB's SIGINT handler | |
687 | then mark the previous handler as not having been saved, and thus it won't | |
688 | be restored. */ | |
689 | ||
690 | static void | |
691 | install_gdb_sigint_handler (struct signal_handler *previous) | |
692 | { | |
693 | /* Save here to simplify comparison. */ | |
694 | RETSIGTYPE (*handle_sigint_for_compare) () = handle_sigint; | |
695 | ||
696 | previous->handler = signal (SIGINT, handle_sigint); | |
697 | if (previous->handler != handle_sigint_for_compare) | |
698 | previous->handler_saved = 1; | |
699 | else | |
700 | previous->handler_saved = 0; | |
701 | } | |
702 | ||
703 | /* Set the currently active extension language to NOW_ACTIVE. | |
704 | The result is a pointer to a malloc'd block of memory to pass to | |
705 | restore_active_ext_lang. | |
706 | ||
707 | N.B. This function must be called every time we call out to an extension | |
708 | language, and the result must be passed to restore_active_ext_lang | |
709 | afterwards. | |
710 | ||
711 | If there is a pending SIGINT it is "moved" to the now active extension | |
712 | language, if it supports cooperative SIGINT handling (i.e., it provides | |
713 | {clear,set,check}_quit_flag methods). If the extension language does not | |
714 | support cooperative SIGINT handling, then the SIGINT is left queued and | |
715 | we require the non-cooperative extension language to call check_quit_flag | |
716 | at appropriate times. | |
717 | It is important for the extension language to call check_quit_flag if it | |
718 | installs its own SIGINT handler to prevent the situation where a SIGINT | |
719 | is queued on entry, extension language code runs for a "long" time possibly | |
720 | serving one or more SIGINTs, and then returns. Upon return, if | |
721 | check_quit_flag is not called, the original SIGINT will be thrown. | |
722 | Non-cooperative extension languages are free to install their own SIGINT | |
723 | handler but the original must be restored upon return, either itself | |
724 | or via restore_active_ext_lang. */ | |
725 | ||
726 | struct active_ext_lang_state * | |
727 | set_active_ext_lang (const struct extension_language_defn *now_active) | |
728 | { | |
729 | struct active_ext_lang_state *previous | |
730 | = XCNEW (struct active_ext_lang_state); | |
731 | ||
732 | previous->ext_lang = active_ext_lang; | |
733 | active_ext_lang = now_active; | |
734 | ||
735 | /* If the newly active extension language uses cooperative SIGINT handling | |
736 | then ensure GDB's SIGINT handler is installed. */ | |
737 | if (now_active->language == EXT_LANG_GDB | |
738 | || now_active->ops->check_quit_flag != NULL) | |
739 | install_gdb_sigint_handler (&previous->sigint_handler); | |
740 | ||
741 | /* If there's a SIGINT recorded in the cooperative extension languages, | |
742 | move it to the new language, or save it in GDB's global flag if the newly | |
743 | active extension language doesn't use cooperative SIGINT handling. */ | |
744 | if (check_quit_flag ()) | |
745 | set_quit_flag (); | |
746 | ||
747 | return previous; | |
748 | } | |
749 | ||
750 | /* Restore active extension language from PREVIOUS. */ | |
751 | ||
752 | void | |
753 | restore_active_ext_lang (struct active_ext_lang_state *previous) | |
754 | { | |
755 | const struct extension_language_defn *current = active_ext_lang; | |
756 | ||
757 | active_ext_lang = previous->ext_lang; | |
758 | ||
759 | /* Restore the previous SIGINT handler if one was saved. */ | |
760 | if (previous->sigint_handler.handler_saved) | |
761 | install_sigint_handler (&previous->sigint_handler); | |
762 | ||
763 | /* If there's a SIGINT recorded in the cooperative extension languages, | |
764 | move it to the new language, or save it in GDB's global flag if the newly | |
765 | active extension language doesn't use cooperative SIGINT handling. */ | |
766 | if (check_quit_flag ()) | |
767 | set_quit_flag (); | |
768 | ||
769 | xfree (previous); | |
770 | } | |
771 | ||
772 | /* Clear the quit flag. | |
773 | The flag is cleared in all extension languages, | |
774 | not just the currently active one. */ | |
775 | ||
776 | void | |
777 | clear_quit_flag (void) | |
778 | { | |
779 | int i; | |
780 | const struct extension_language_defn *extlang; | |
781 | ||
782 | ALL_ENABLED_EXTENSION_LANGUAGES (i, extlang) | |
783 | { | |
784 | if (extlang->ops->clear_quit_flag != NULL) | |
785 | extlang->ops->clear_quit_flag (extlang); | |
786 | } | |
787 | ||
788 | quit_flag = 0; | |
789 | } | |
790 | ||
791 | /* Set the quit flag. | |
792 | This only sets the flag in the currently active extension language. | |
793 | If the currently active extension language does not have cooperative | |
794 | SIGINT handling, then GDB's global flag is set, and it is up to the | |
795 | extension language to call check_quit_flag. The extension language | |
796 | is free to install its own SIGINT handler, but we still need to handle | |
797 | the transition. */ | |
798 | ||
799 | void | |
800 | set_quit_flag (void) | |
801 | { | |
802 | if (active_ext_lang->ops != NULL | |
803 | && active_ext_lang->ops->set_quit_flag != NULL) | |
804 | active_ext_lang->ops->set_quit_flag (active_ext_lang); | |
805 | else | |
806 | quit_flag = 1; | |
807 | } | |
808 | ||
809 | /* Return true if the quit flag has been set, false otherwise. | |
810 | Note: The flag is cleared as a side-effect. | |
811 | The flag is checked in all extension languages that support cooperative | |
812 | SIGINT handling, not just the current one. This simplifies transitions. */ | |
813 | ||
814 | int | |
815 | check_quit_flag (void) | |
816 | { | |
817 | int i, result = 0; | |
818 | const struct extension_language_defn *extlang; | |
819 | ||
820 | ALL_ENABLED_EXTENSION_LANGUAGES (i, extlang) | |
821 | { | |
822 | if (extlang->ops->check_quit_flag != NULL) | |
823 | if (extlang->ops->check_quit_flag (extlang) != 0) | |
824 | result = 1; | |
825 | } | |
826 | ||
827 | /* This is written in a particular way to avoid races. */ | |
828 | if (quit_flag) | |
829 | { | |
830 | quit_flag = 0; | |
831 | result = 1; | |
832 | } | |
833 | ||
834 | return result; | |
835 | } | |
836 | \f | |
e81e7f5e SC |
837 | /* xmethod support. */ |
838 | ||
839 | /* The xmethod API routines do not have "ext_lang" in the name because | |
840 | the name "xmethod" implies that this routine deals with extension | |
841 | languages. Plus some of the methods take a xmethod_foo * "self/this" | |
842 | arg, not an extension_language_defn * arg. */ | |
843 | ||
844 | /* Returns a new xmethod_worker with EXTLANG and DATA. Space for the | |
845 | result must be freed with free_xmethod_worker. */ | |
846 | ||
847 | struct xmethod_worker * | |
848 | new_xmethod_worker (const struct extension_language_defn *extlang, void *data) | |
849 | { | |
850 | struct xmethod_worker *worker = XCNEW (struct xmethod_worker); | |
851 | ||
852 | worker->extlang = extlang; | |
853 | worker->data = data; | |
854 | worker->value = NULL; | |
855 | ||
856 | return worker; | |
857 | } | |
858 | ||
859 | /* Clones WORKER and returns a new but identical worker. | |
860 | The function get_matching_xmethod_workers (see below), returns a | |
861 | vector of matching workers. If a particular worker is selected by GDB | |
862 | to invoke a method, then this function can help in cloning the | |
863 | selected worker and freeing up the vector via a cleanup. | |
864 | ||
865 | Space for the result must be freed with free_xmethod_worker. */ | |
866 | ||
867 | struct xmethod_worker * | |
868 | clone_xmethod_worker (struct xmethod_worker *worker) | |
869 | { | |
870 | struct xmethod_worker *new_worker; | |
871 | const struct extension_language_defn *extlang = worker->extlang; | |
872 | ||
873 | gdb_assert (extlang->ops->clone_xmethod_worker_data != NULL); | |
874 | ||
875 | new_worker = new_xmethod_worker | |
876 | (extlang, | |
877 | extlang->ops->clone_xmethod_worker_data (extlang, worker->data)); | |
878 | ||
879 | return new_worker; | |
880 | } | |
881 | ||
882 | /* If a method with name METHOD_NAME is to be invoked on an object of type | |
883 | TYPE, then all entension languages are searched for implementations of | |
884 | methods with name METHOD. All matches found are returned as a vector | |
885 | of 'xmethod_worker_ptr' objects. If no matching methods are | |
886 | found, NULL is returned. */ | |
887 | ||
888 | VEC (xmethod_worker_ptr) * | |
889 | get_matching_xmethod_workers (struct type *type, const char *method_name) | |
890 | { | |
891 | VEC (xmethod_worker_ptr) *workers = NULL; | |
892 | int i; | |
893 | const struct extension_language_defn *extlang; | |
894 | ||
895 | ALL_ENABLED_EXTENSION_LANGUAGES (i, extlang) | |
896 | { | |
897 | VEC (xmethod_worker_ptr) *lang_workers, *new_vec; | |
898 | enum ext_lang_rc rc; | |
899 | ||
900 | /* If an extension language does not support xmethods, ignore | |
901 | it. */ | |
902 | if (extlang->ops->get_matching_xmethod_workers == NULL) | |
903 | continue; | |
904 | ||
905 | rc = extlang->ops->get_matching_xmethod_workers (extlang, | |
906 | type, method_name, | |
907 | &lang_workers); | |
908 | if (rc == EXT_LANG_RC_ERROR) | |
909 | { | |
910 | free_xmethod_worker_vec (workers); | |
911 | error (_("Error while looking for matching xmethod workers " | |
912 | "defined in %s."), extlang->capitalized_name); | |
913 | } | |
914 | ||
915 | new_vec = VEC_merge (xmethod_worker_ptr, workers, lang_workers); | |
916 | /* Free only the vectors and not the elements as NEW_VEC still | |
917 | contains them. */ | |
918 | VEC_free (xmethod_worker_ptr, workers); | |
919 | VEC_free (xmethod_worker_ptr, lang_workers); | |
920 | workers = new_vec; | |
921 | } | |
922 | ||
923 | return workers; | |
924 | } | |
925 | ||
926 | /* Return the arg types of the xmethod encapsulated in WORKER. | |
927 | An array of arg types is returned. The length of the array is returned in | |
928 | NARGS. The type of the 'this' object is returned as the first element of | |
929 | array. */ | |
930 | ||
931 | struct type ** | |
932 | get_xmethod_arg_types (struct xmethod_worker *worker, int *nargs) | |
933 | { | |
934 | enum ext_lang_rc rc; | |
935 | struct type **type_array = NULL; | |
936 | const struct extension_language_defn *extlang = worker->extlang; | |
937 | ||
938 | gdb_assert (extlang->ops->get_xmethod_arg_types != NULL); | |
939 | ||
940 | rc = extlang->ops->get_xmethod_arg_types (extlang, worker, nargs, | |
941 | &type_array); | |
942 | if (rc == EXT_LANG_RC_ERROR) | |
943 | { | |
944 | error (_("Error while looking for arg types of a xmethod worker " | |
945 | "defined in %s."), extlang->capitalized_name); | |
946 | } | |
947 | ||
948 | return type_array; | |
949 | } | |
950 | ||
951 | /* Invokes the xmethod encapsulated in WORKER and returns the result. | |
952 | The method is invoked on OBJ with arguments in the ARGS array. NARGS is | |
953 | the length of the this array. */ | |
954 | ||
955 | struct value * | |
956 | invoke_xmethod (struct xmethod_worker *worker, struct value *obj, | |
957 | struct value **args, int nargs) | |
958 | { | |
959 | gdb_assert (worker->extlang->ops->invoke_xmethod != NULL); | |
960 | ||
961 | return worker->extlang->ops->invoke_xmethod (worker->extlang, worker, | |
962 | obj, args, nargs); | |
963 | } | |
964 | ||
965 | /* Frees the xmethod worker WORKER. */ | |
966 | ||
967 | void | |
968 | free_xmethod_worker (struct xmethod_worker *worker) | |
969 | { | |
970 | gdb_assert (worker->extlang->ops->free_xmethod_worker_data != NULL); | |
971 | worker->extlang->ops->free_xmethod_worker_data (worker->extlang, | |
972 | worker->data); | |
973 | xfree (worker); | |
974 | } | |
975 | ||
976 | /* Frees a vector of xmethod_workers VEC. */ | |
977 | ||
978 | void | |
979 | free_xmethod_worker_vec (void *vec) | |
980 | { | |
981 | int i; | |
982 | struct xmethod_worker *worker; | |
983 | VEC (xmethod_worker_ptr) *v = (VEC (xmethod_worker_ptr) *) vec; | |
984 | ||
985 | for (i = 0; VEC_iterate (xmethod_worker_ptr, v, i, worker); i++) | |
986 | free_xmethod_worker (worker); | |
987 | ||
988 | VEC_free (xmethod_worker_ptr, v); | |
989 | } | |
990 | \f | |
6dddc817 DE |
991 | /* Called via an observer before gdb prints its prompt. |
992 | Iterate over the extension languages giving them a chance to | |
993 | change the prompt. The first one to change the prompt wins, | |
994 | and no further languages are tried. */ | |
995 | ||
996 | static void | |
997 | ext_lang_before_prompt (const char *current_gdb_prompt) | |
998 | { | |
999 | int i; | |
1000 | const struct extension_language_defn *extlang; | |
1001 | ||
1002 | ALL_ENABLED_EXTENSION_LANGUAGES (i, extlang) | |
1003 | { | |
1004 | enum ext_lang_rc rc; | |
1005 | ||
1006 | if (extlang->ops->before_prompt == NULL) | |
1007 | continue; | |
1008 | rc = extlang->ops->before_prompt (extlang, current_gdb_prompt); | |
1009 | switch (rc) | |
1010 | { | |
1011 | case EXT_LANG_RC_OK: | |
1012 | case EXT_LANG_RC_ERROR: | |
1013 | return; | |
1014 | case EXT_LANG_RC_NOP: | |
1015 | break; | |
1016 | default: | |
1017 | gdb_assert_not_reached ("bad return from before_prompt"); | |
1018 | } | |
1019 | } | |
1020 | } | |
1021 | ||
1022 | extern initialize_file_ftype _initialize_extension; | |
1023 | ||
1024 | void | |
1025 | _initialize_extension (void) | |
1026 | { | |
1027 | observer_attach_before_prompt (ext_lang_before_prompt); | |
1028 | } |