xref: /illumos-gate/usr/src/tools/smatch/src/smatch_db.c (revision 22028508fd28d36ff74dc02c5774a8ba1f0db045)
1 /*
2  * Copyright (C) 2010 Dan Carpenter.
3  *
4  * This program is free software; you can redistribute it and/or
5  * modify it under the terms of the GNU General Public License
6  * as published by the Free Software Foundation; either version 2
7  * of the License, or (at your option) any later version.
8  *
9  * This program is distributed in the hope that it will be useful,
10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
12  * GNU General Public License for more details.
13  *
14  * You should have received a copy of the GNU General Public License
15  * along with this program; if not, see http://www.gnu.org/copyleft/gpl.txt
16  */
17 
18 #include <string.h>
19 #include <errno.h>
20 #include <unistd.h>
21 #include <ctype.h>
22 #include "smatch.h"
23 #include "smatch_slist.h"
24 #include "smatch_extra.h"
25 
26 struct sqlite3 *smatch_db;
27 struct sqlite3 *mem_db;
28 struct sqlite3 *cache_db;
29 
30 int debug_db;
31 
32 static int return_id;
33 
34 static void call_return_state_hooks(struct expression *expr);
35 
36 #define SQLITE_CACHE_PAGES 1000
37 
38 struct def_callback {
39 	int hook_type;
40 	void (*callback)(const char *name, struct symbol *sym, char *key, char *value);
41 };
42 ALLOCATOR(def_callback, "definition db hook callbacks");
43 DECLARE_PTR_LIST(callback_list, struct def_callback);
44 static struct callback_list *select_caller_info_callbacks;
45 
46 struct member_info_callback {
47 	int owner;
48 	void (*callback)(struct expression *call, int param, char *printed_name, struct sm_state *sm);
49 };
50 ALLOCATOR(member_info_callback, "caller_info callbacks");
51 DECLARE_PTR_LIST(member_info_cb_list, struct member_info_callback);
52 static struct member_info_cb_list *member_callbacks;
53 static struct member_info_cb_list *member_callbacks_new;
54 
55 struct returned_state_callback {
56 	void (*callback)(int return_id, char *return_ranges, struct expression *return_expr);
57 };
58 ALLOCATOR(returned_state_callback, "returned state callbacks");
59 DECLARE_PTR_LIST(returned_state_cb_list, struct returned_state_callback);
60 static struct returned_state_cb_list *returned_state_callbacks;
61 
62 struct returned_member_callback {
63 	int owner;
64 	void (*callback)(int return_id, char *return_ranges, struct expression *expr, char *printed_name, struct smatch_state *state);
65 };
66 ALLOCATOR(returned_member_callback, "returned member callbacks");
67 DECLARE_PTR_LIST(returned_member_cb_list, struct returned_member_callback);
68 static struct returned_member_cb_list *returned_member_callbacks;
69 
70 struct db_implies_callback {
71 	int type;
72 	void (*callback)(struct expression *call, struct expression *arg, char *key, char *value);
73 };
74 ALLOCATOR(db_implies_callback, "return_implies callbacks");
75 DECLARE_PTR_LIST(db_implies_cb_list, struct db_implies_callback);
76 static struct db_implies_cb_list *return_implies_cb_list;
77 static struct db_implies_cb_list *call_implies_cb_list;
78 
79 /* silently truncates if needed. */
80 char *escape_newlines(const char *str)
81 {
82 	char buf[1024] = "";
83 	bool found = false;
84 	int i, j;
85 
86 	for (i = 0, j = 0; str[i] != '\0' && j != sizeof(buf); i++, j++) {
87 		if (str[i] != '\r' && str[i] != '\n') {
88 			buf[j] = str[i];
89 			continue;
90 		}
91 
92 		found = true;
93 		buf[j++] = '\\';
94 		if (j == sizeof(buf))
95 			 break;
96 		buf[j] = 'n';
97 	}
98 
99 	if (!found)
100 		return alloc_sname(str);
101 
102 	if (j == sizeof(buf))
103 		buf[j - 1] = '\0';
104 	return alloc_sname(buf);
105 }
106 
107 static int print_sql_output(void *unused, int argc, char **argv, char **azColName)
108 {
109 	int i;
110 
111 	for (i = 0; i < argc; i++) {
112 		if (i != 0)
113 			sm_printf(", ");
114 		sm_printf("%s", argv[i]);
115 	}
116 	sm_printf("\n");
117 	return 0;
118 }
119 
120 void sql_exec(struct sqlite3 *db, int (*callback)(void*, int, char**, char**), void *data, const char *sql)
121 {
122 	char *err = NULL;
123 	int rc;
124 
125 	if (!db)
126 		return;
127 
128 	if (option_debug || debug_db) {
129 		sm_msg("%s", sql);
130 		if (strncasecmp(sql, "select", strlen("select")) == 0)
131 			sqlite3_exec(db, sql, print_sql_output, NULL, NULL);
132 	}
133 
134 	rc = sqlite3_exec(db, sql, callback, data, &err);
135 	if (rc != SQLITE_OK && !parse_error) {
136 		sm_ierror("%s:%d SQL error #2: %s\n", get_filename(), get_lineno(), err);
137 		sm_ierror("%s:%d SQL: '%s'\n", get_filename(), get_lineno(), sql);
138 		parse_error = 1;
139 	}
140 }
141 
142 static int replace_count;
143 static char **replace_table;
144 static const char *replace_return_ranges(const char *return_ranges)
145 {
146 	int i;
147 
148 	if (!get_function()) {
149 		/* I have no idea why EXPORT_SYMBOL() is here */
150 		return return_ranges;
151 	}
152 	for (i = 0; i < replace_count; i += 3) {
153 		if (strcmp(replace_table[i + 0], get_function()) == 0) {
154 			if (strcmp(replace_table[i + 1], return_ranges) == 0)
155 				return replace_table[i + 2];
156 		}
157 	}
158 	return return_ranges;
159 }
160 
161 
162 static char *use_states;
163 static int get_db_state_count(void)
164 {
165 	struct sm_state *sm;
166 	int count = 0;
167 
168 	FOR_EACH_SM(__get_cur_stree(), sm) {
169 		if (sm->owner == USHRT_MAX)
170 			continue;
171 		if (use_states[sm->owner])
172 			count++;
173 	} END_FOR_EACH_SM(sm);
174 	return count;
175 }
176 
177 void db_ignore_states(int id)
178 {
179 	use_states[id] = 0;
180 }
181 
182 unsigned long long __fn_mtag;
183 static void set_fn_mtag(struct symbol *sym)
184 {
185 	char buf[128];
186 
187 	if (cur_func_sym->ctype.modifiers & MOD_STATIC)
188 		snprintf(buf, sizeof(buf), "%s %s", get_base_file(), get_function());
189 	else
190 		snprintf(buf, sizeof(buf), "extern %s", get_function());
191 
192 	__fn_mtag = str_to_mtag(buf);
193 }
194 
195 void sql_insert_return_states(int return_id, const char *return_ranges,
196 		int type, int param, const char *key, const char *value)
197 {
198 	unsigned long long id;
199 
200 
201 	if (key && strlen(key) >= 80)
202 		return;
203 	if (__inline_fn)
204 		id = (unsigned long)__inline_fn;
205 	else
206 		id = __fn_mtag;
207 
208 	return_ranges = replace_return_ranges(return_ranges);
209 	sql_insert(return_states, "'%s', '%s', %llu, %d, '%s', %d, %d, %d, '%s', '%s'",
210 		   get_base_file(), get_function(), id, return_id,
211 		   return_ranges, fn_static(), type, param, key, value);
212 }
213 
214 static struct string_list *common_funcs;
215 static int is_common_function(const char *fn)
216 {
217 	char *tmp;
218 
219 	if (!fn)
220 		return 0;
221 
222 	if (strncmp(fn, "__builtin_", 10) == 0)
223 		return 1;
224 
225 	FOR_EACH_PTR(common_funcs, tmp) {
226 		if (strcmp(tmp, fn) == 0)
227 			return 1;
228 	} END_FOR_EACH_PTR(tmp);
229 
230 	return 0;
231 }
232 
233 static char *function_signature(void)
234 {
235 	return type_to_str(get_real_base_type(cur_func_sym));
236 }
237 
238 void sql_insert_caller_info(struct expression *call, int type,
239 		int param, const char *key, const char *value)
240 {
241 	FILE *tmp_fd = sm_outfd;
242 	char *fn;
243 
244 	if (!option_info && !__inline_call)
245 		return;
246 
247 	if (key && strlen(key) >= 80)
248 		return;
249 
250 	fn = get_fnptr_name(call->fn);
251 	if (!fn)
252 		return;
253 
254 	if (__inline_call) {
255 		mem_sql(NULL, NULL,
256 			"insert into caller_info values ('%s', '%s', '%s', %lu, %d, %d, %d, '%s', '%s');",
257 			get_base_file(), get_function(), fn, (unsigned long)call,
258 			is_static(call->fn), type, param, key, value);
259 	}
260 
261 	if (!option_info)
262 		return;
263 
264 	if (strncmp(fn, "__builtin_", 10) == 0)
265 		return;
266 	if (type != INTERNAL && is_common_function(fn))
267 		return;
268 
269 	sm_outfd = caller_info_fd;
270 	sm_msg("SQL_caller_info: insert into caller_info values ("
271 	       "'%s', '%s', '%s', %%CALL_ID%%, %d, %d, %d, '%s', '%s');",
272 	       get_base_file(), get_function(), fn, is_static(call->fn),
273 	       type, param, key, value);
274 	sm_outfd = tmp_fd;
275 
276 	free_string(fn);
277 }
278 
279 void sql_insert_function_ptr(const char *fn, const char *struct_name)
280 {
281 	sql_insert_or_ignore(function_ptr, "'%s', '%s', '%s', 0",
282 			     get_base_file(), fn, struct_name);
283 }
284 
285 void sql_insert_return_implies(int type, int param, const char *key, const char *value)
286 {
287 	sql_insert_or_ignore(return_implies, "'%s', '%s', %lu, %d, %d, %d, '%s', '%s'",
288 		get_base_file(), get_function(), (unsigned long)__inline_fn,
289 		fn_static(), type, param, key, value);
290 }
291 
292 void sql_insert_call_implies(int type, int param, const char *key, const char *value)
293 {
294 	sql_insert_or_ignore(call_implies, "'%s', '%s', %lu, %d, %d, %d, '%s', '%s'",
295 		get_base_file(), get_function(), (unsigned long)__inline_fn,
296 		fn_static(), type, param, key, value);
297 }
298 
299 void sql_insert_function_type_size(const char *member, const char *ranges)
300 {
301 	sql_insert(function_type_size, "'%s', '%s', '%s', '%s'", get_base_file(), get_function(), member, ranges);
302 }
303 
304 void sql_insert_function_type_info(int type, const char *struct_type, const char *member, const char *value)
305 {
306 	sql_insert(function_type_info, "'%s', '%s', %d, '%s', '%s', '%s'", get_base_file(), get_function(), type, struct_type, member, value);
307 }
308 
309 void sql_insert_type_info(int type, const char *member, const char *value)
310 {
311 	sql_insert_cache(type_info, "'%s', %d, '%s', '%s'", get_base_file(), type, member, value);
312 }
313 
314 void sql_insert_local_values(const char *name, const char *value)
315 {
316 	sql_insert(local_values, "'%s', '%s', '%s'", get_base_file(), name, value);
317 }
318 
319 void sql_insert_function_type_value(const char *type, const char *value)
320 {
321 	sql_insert(function_type_value, "'%s', '%s', '%s', '%s'", get_base_file(), get_function(), type, value);
322 }
323 
324 void sql_insert_function_type(int param, const char *value)
325 {
326 	sql_insert(function_type, "'%s', '%s', %d, %d, '%s'",
327 		   get_base_file(), get_function(), fn_static(), param, value);
328 }
329 
330 void sql_insert_parameter_name(int param, const char *value)
331 {
332 	sql_insert(parameter_name, "'%s', '%s', %d, %d, '%s'",
333 		   get_base_file(), get_function(), fn_static(), param, value);
334 }
335 
336 void sql_insert_data_info(struct expression *data, int type, const char *value)
337 {
338 	char *data_name;
339 
340 	data_name = get_data_info_name(data);
341 	if (!data_name)
342 		return;
343 	sql_insert(data_info, "'%s', '%s', %d, '%s'",
344 		   is_static(data) ? get_base_file() : "extern",
345 		   data_name, type, value);
346 }
347 
348 void sql_insert_data_info_var_sym(const char *var, struct symbol *sym, int type, const char *value)
349 {
350 	sql_insert(data_info, "'%s', '%s', %d, '%s'",
351 		   (sym->ctype.modifiers & MOD_STATIC) ? get_base_file() : "extern",
352 		   var, type, value);
353 }
354 
355 void sql_save_constraint(const char *con)
356 {
357 	if (!option_info)
358 		return;
359 
360         sm_msg("SQL: insert or ignore into constraints (str) values('%s');", escape_newlines(con));
361 }
362 
363 void sql_save_constraint_required(const char *data, int op, const char *limit)
364 {
365 	sql_insert_or_ignore(constraints_required, "'%s', '%s', '%s'", data, show_special(op), limit);
366 }
367 
368 void sql_copy_constraint_required(const char *new_limit, const char *old_limit)
369 {
370 	if (!option_info)
371 		return;
372 
373 	sm_msg("SQL_late: insert or ignore into constraints_required (data, op, bound) "
374 		"select constraints_required.data, constraints_required.op, '%s' from "
375 		"constraints_required where bound = '%s';", new_limit, old_limit);
376 }
377 
378 void sql_insert_fn_ptr_data_link(const char *ptr, const char *data)
379 {
380 	sql_insert_or_ignore(fn_ptr_data_link, "'%s', '%s'", ptr, data);
381 }
382 
383 void sql_insert_fn_data_link(struct expression *fn, int type, int param, const char *key, const char *value)
384 {
385 	if (fn->type != EXPR_SYMBOL || !fn->symbol->ident)
386 		return;
387 
388 	sql_insert(fn_data_link, "'%s', '%s', %d, %d, %d, '%s', '%s'",
389 		   (fn->symbol->ctype.modifiers & MOD_STATIC) ? get_base_file() : "extern",
390 		   fn->symbol->ident->name,
391 		   !!(fn->symbol->ctype.modifiers & MOD_STATIC),
392 		   type, param, key, value);
393 }
394 
395 void sql_insert_mtag_about(mtag_t tag, const char *left_name, const char *right_name)
396 {
397 	sql_insert_cache(mtag_about, "%lld, '%s', '%s', %d, '%s', '%s'",
398 			 tag, get_filename(), get_function(), get_lineno(),
399 			 left_name, right_name);
400 }
401 
402 void sql_insert_mtag_info(mtag_t tag, int type, const char *value)
403 {
404 	sql_insert_cache(mtag_info, "'%s', %lld, %d, '%s'", get_filename(), tag, type, value);
405 }
406 
407 void sql_insert_mtag_map(mtag_t container, int container_offset, mtag_t tag, int tag_offset)
408 {
409 	sql_insert(mtag_map, "%lld, %d, %lld, %d", container, container_offset, tag, tag_offset);
410 }
411 
412 void sql_insert_mtag_alias(mtag_t orig, mtag_t alias)
413 {
414 	sql_insert(mtag_alias, "%lld, %lld", orig, alias);
415 }
416 
417 static int save_mtag(void *_tag, int argc, char **argv, char **azColName)
418 {
419 	mtag_t *saved_tag = _tag;
420 	mtag_t new_tag;
421 
422 	new_tag = strtoll(argv[0], NULL, 10);
423 
424 	if (!*saved_tag)
425 		*saved_tag = new_tag;
426 	else if (*saved_tag != new_tag)
427 		*saved_tag = -1ULL;
428 
429 	return 0;
430 }
431 
432 int mtag_map_select_container(mtag_t tag, int container_offset, mtag_t *container)
433 {
434 	mtag_t tmp = 0;
435 
436 	run_sql(save_mtag, &tmp,
437 		"select container from mtag_map where tag = %lld and container_offset = %d and tag_offset = 0;",
438 		tag, container_offset);
439 
440 	if (tmp == 0 || tmp == -1ULL)
441 		return 0;
442 	*container = tmp;
443 	return 1;
444 }
445 
446 int mtag_map_select_tag(mtag_t container, int offset, mtag_t *tag)
447 {
448 	mtag_t tmp = 0;
449 
450 	run_sql(save_mtag, &tmp,
451 		"select tag from mtag_map where container = %lld and container_offset = %d;",
452 		container, offset);
453 
454 	if (tmp == 0 || tmp == -1ULL)
455 		return 0;
456 	*tag = tmp;
457 	return 1;
458 }
459 
460 char *get_static_filter(struct symbol *sym)
461 {
462 	static char sql_filter[1024];
463 
464 	/* This can only happen on buggy code.  Return invalid SQL. */
465 	if (!sym) {
466 		sql_filter[0] = '\0';
467 		return sql_filter;
468 	}
469 
470 	if (sym->ctype.modifiers & MOD_STATIC) {
471 		snprintf(sql_filter, sizeof(sql_filter),
472 			 "file = '%s' and function = '%s' and static = '1'",
473 			 get_base_file(), sym->ident->name);
474 	} else {
475 		snprintf(sql_filter, sizeof(sql_filter),
476 			 "function = '%s' and static = '0'", sym->ident->name);
477 	}
478 
479 	return sql_filter;
480 }
481 
482 static int get_row_count(void *_row_count, int argc, char **argv, char **azColName)
483 {
484 	int *row_count = _row_count;
485 
486 	*row_count = 0;
487 	if (argc != 1)
488 		return 0;
489 	*row_count = atoi(argv[0]);
490 	return 0;
491 }
492 
493 static void mark_call_params_untracked(struct expression *call)
494 {
495 	struct expression *arg;
496 	int i = 0;
497 
498 	FOR_EACH_PTR(call->args, arg) {
499 		mark_untracked(call, i++, "$", NULL);
500 	} END_FOR_EACH_PTR(arg);
501 }
502 
503 static void sql_select_return_states_pointer(const char *cols,
504 	struct expression *call, int (*callback)(void*, int, char**, char**), void *info)
505 {
506 	char *ptr;
507 	int return_count = 0;
508 
509 	ptr = get_fnptr_name(call->fn);
510 	if (!ptr)
511 		return;
512 
513 	run_sql(get_row_count, &return_count,
514 		"select count(*) from return_states join function_ptr "
515 		"where return_states.function == function_ptr.function and "
516 		"ptr = '%s' and searchable = 1 and type = %d;", ptr, INTERNAL);
517 	/* The magic number 100 is just from testing on the kernel. */
518 	if (return_count > 100) {
519 		mark_call_params_untracked(call);
520 		return;
521 	}
522 
523 	run_sql(callback, info,
524 		"select %s from return_states join function_ptr where "
525 		"return_states.function == function_ptr.function and ptr = '%s' "
526 		"and searchable = 1 "
527 		"order by function_ptr.file, return_states.file, return_id, type;",
528 		cols, ptr);
529 }
530 
531 static int is_local_symbol(struct expression *expr)
532 {
533 	if (expr->type != EXPR_SYMBOL)
534 		return 0;
535 	if (expr->symbol->ctype.modifiers & (MOD_NONLOCAL | MOD_STATIC | MOD_ADDRESSABLE))
536 		return 0;
537 	return 1;
538 }
539 
540 void sql_select_return_states(const char *cols, struct expression *call,
541 	int (*callback)(void*, int, char**, char**), void *info)
542 {
543 	struct expression *fn;
544 	int row_count = 0;
545 
546 	if (is_fake_call(call))
547 		return;
548 
549 	fn = strip_expr(call->fn);
550 	if (fn->type != EXPR_SYMBOL || !fn->symbol || is_local_symbol(fn)) {
551 		sql_select_return_states_pointer(cols, call, callback, info);
552 		return;
553 	}
554 
555 	if (inlinable(fn)) {
556 		mem_sql(callback, info,
557 			"select %s from return_states where call_id = '%lu' order by return_id, type;",
558 			cols, (unsigned long)call);
559 		return;
560 	}
561 
562 	run_sql(get_row_count, &row_count, "select count(*) from return_states where %s;",
563 		get_static_filter(fn->symbol));
564 	if (row_count > 3000)
565 		return;
566 
567 	run_sql(callback, info, "select %s from return_states where %s order by file, return_id, type;",
568 		cols, get_static_filter(fn->symbol));
569 }
570 
571 #define CALL_IMPLIES 0
572 #define RETURN_IMPLIES 1
573 
574 struct implies_info {
575 	int type;
576 	struct db_implies_cb_list *cb_list;
577 	struct expression *expr;
578 	struct symbol *sym;
579 };
580 
581 void sql_select_implies(const char *cols, struct implies_info *info,
582 	int (*callback)(void*, int, char**, char**))
583 {
584 	if (info->type == RETURN_IMPLIES && inlinable(info->expr->fn)) {
585 		mem_sql(callback, info,
586 			"select %s from return_implies where call_id = '%lu';",
587 			cols, (unsigned long)info->expr);
588 		return;
589 	}
590 
591 	run_sql(callback, info, "select %s from %s_implies where %s;",
592 		cols,
593 		info->type == CALL_IMPLIES ? "call" : "return",
594 		get_static_filter(info->sym));
595 }
596 
597 struct select_caller_info_data {
598 	struct stree *final_states;
599 	struct timeval start_time;
600 	int prev_func_id;
601 	int ignore;
602 	int results;
603 };
604 
605 static int caller_info_callback(void *_data, int argc, char **argv, char **azColName);
606 
607 static void sql_select_caller_info(struct select_caller_info_data *data,
608 	const char *cols, struct symbol *sym)
609 {
610 	if (__inline_fn) {
611 		mem_sql(caller_info_callback, data,
612 			"select %s from caller_info where call_id = %lu;",
613 			cols, (unsigned long)__inline_fn);
614 		return;
615 	}
616 
617 	if (sym->ident->name && is_common_function(sym->ident->name))
618 		return;
619 	run_sql(caller_info_callback, data,
620 		"select %s from common_caller_info where %s order by call_id;",
621 		cols, get_static_filter(sym));
622 	if (data->results)
623 		return;
624 
625 	run_sql(caller_info_callback, data,
626 		"select %s from caller_info where %s order by call_id;",
627 		cols, get_static_filter(sym));
628 }
629 
630 void select_caller_info_hook(void (*callback)(const char *name, struct symbol *sym, char *key, char *value), int type)
631 {
632 	struct def_callback *def_callback = __alloc_def_callback(0);
633 
634 	def_callback->hook_type = type;
635 	def_callback->callback = callback;
636 	add_ptr_list(&select_caller_info_callbacks, def_callback);
637 }
638 
639 /*
640  * These call backs are used when the --info option is turned on to print struct
641  * member information.  For example foo->bar could have a state in
642  * smatch_extra.c and also check_user.c.
643  */
644 void add_member_info_callback(int owner, void (*callback)(struct expression *call, int param, char *printed_name, struct sm_state *sm))
645 {
646 	struct member_info_callback *member_callback = __alloc_member_info_callback(0);
647 
648 	member_callback->owner = owner;
649 	member_callback->callback = callback;
650 	add_ptr_list(&member_callbacks, member_callback);
651 }
652 
653 void add_caller_info_callback(int owner, void (*callback)(struct expression *call, int param, char *printed_name, struct sm_state *sm))
654 {
655 	struct member_info_callback *member_callback = __alloc_member_info_callback(0);
656 
657 	member_callback->owner = owner;
658 	member_callback->callback = callback;
659 	add_ptr_list(&member_callbacks_new, member_callback);
660 }
661 
662 void add_split_return_callback(void (*fn)(int return_id, char *return_ranges, struct expression *returned_expr))
663 {
664 	struct returned_state_callback *callback = __alloc_returned_state_callback(0);
665 
666 	callback->callback = fn;
667 	add_ptr_list(&returned_state_callbacks, callback);
668 }
669 
670 void add_returned_member_callback(int owner, void (*callback)(int return_id, char *return_ranges, struct expression *expr, char *printed_name, struct smatch_state *state))
671 {
672 	struct returned_member_callback *member_callback = __alloc_returned_member_callback(0);
673 
674 	member_callback->owner = owner;
675 	member_callback->callback = callback;
676 	add_ptr_list(&returned_member_callbacks, member_callback);
677 }
678 
679 void select_call_implies_hook(int type, void (*callback)(struct expression *call, struct expression *arg, char *key, char *value))
680 {
681 	struct db_implies_callback *cb = __alloc_db_implies_callback(0);
682 
683 	cb->type = type;
684 	cb->callback = callback;
685 	add_ptr_list(&call_implies_cb_list, cb);
686 }
687 
688 void select_return_implies_hook(int type, void (*callback)(struct expression *call, struct expression *arg, char *key, char *value))
689 {
690 	struct db_implies_callback *cb = __alloc_db_implies_callback(0);
691 
692 	cb->type = type;
693 	cb->callback = callback;
694 	add_ptr_list(&return_implies_cb_list, cb);
695 }
696 
697 struct return_info {
698 	struct expression *static_returns_call;
699 	struct symbol *return_type;
700 	struct range_list *return_range_list;
701 };
702 
703 static int db_return_callback(void *_ret_info, int argc, char **argv, char **azColName)
704 {
705 	struct return_info *ret_info = _ret_info;
706 	struct range_list *rl;
707 	struct expression *call_expr = ret_info->static_returns_call;
708 
709 	if (argc != 1)
710 		return 0;
711 	call_results_to_rl(call_expr, ret_info->return_type, argv[0], &rl);
712 	ret_info->return_range_list = rl_union(ret_info->return_range_list, rl);
713 	return 0;
714 }
715 
716 struct range_list *db_return_vals(struct expression *expr)
717 {
718 	struct return_info ret_info = {};
719 	char buf[64];
720 	struct sm_state *sm;
721 
722 	if (is_fake_call(expr))
723 		return NULL;
724 
725 	snprintf(buf, sizeof(buf), "return %p", expr);
726 	sm = get_sm_state(SMATCH_EXTRA, buf, NULL);
727 	if (sm)
728 		return clone_rl(estate_rl(sm->state));
729 	ret_info.static_returns_call = expr;
730 	ret_info.return_type = get_type(expr);
731 	if (!ret_info.return_type)
732 		return NULL;
733 
734 	if (expr->fn->type != EXPR_SYMBOL || !expr->fn->symbol)
735 		return NULL;
736 
737 	ret_info.return_range_list = NULL;
738 	if (inlinable(expr->fn)) {
739 		mem_sql(db_return_callback, &ret_info,
740 			"select distinct return from return_states where call_id = '%lu';",
741 			(unsigned long)expr);
742 	} else {
743 		run_sql(db_return_callback, &ret_info,
744 			"select distinct return from return_states where %s;",
745 			get_static_filter(expr->fn->symbol));
746 	}
747 	return ret_info.return_range_list;
748 }
749 
750 struct range_list *db_return_vals_from_str(const char *fn_name)
751 {
752 	struct return_info ret_info;
753 
754 	ret_info.static_returns_call = NULL;
755 	ret_info.return_type = &llong_ctype;
756 	ret_info.return_range_list = NULL;
757 
758 	run_sql(db_return_callback, &ret_info,
759 		"select distinct return from return_states where function = '%s';",
760 		fn_name);
761 	return ret_info.return_range_list;
762 }
763 
764 /*
765  * This is used when we have a function that takes a function pointer as a
766  * parameter.  "frob(blah, blah, my_function);"  We know that the return values
767  * from frob() come from my_funcion() so we want to find the possible returns
768  * of my_function(), but we don't know which arguments are passed to it.
769  *
770  */
771 struct range_list *db_return_vals_no_args(struct expression *expr)
772 {
773 	struct return_info ret_info = {};
774 
775 	if (!expr || expr->type != EXPR_SYMBOL)
776 		return NULL;
777 
778 	ret_info.static_returns_call = expr;
779 	ret_info.return_type = get_type(expr);
780 	ret_info.return_type = get_real_base_type(ret_info.return_type);
781 	if (!ret_info.return_type)
782 		return NULL;
783 
784 	run_sql(db_return_callback, &ret_info,
785 		"select distinct return from return_states where %s;",
786 		get_static_filter(expr->symbol));
787 
788 	return ret_info.return_range_list;
789 }
790 
791 static void match_call_marker(struct expression *expr)
792 {
793 	struct symbol *type;
794 
795 	type = get_type(expr->fn);
796 	if (type && type->type == SYM_PTR)
797 		type = get_real_base_type(type);
798 
799 	/*
800 	 * we just want to record something in the database so that if we have
801 	 * two calls like:  frob(4); frob(some_unkown); then on the receiving
802 	 * side we know that sometimes frob is called with unknown parameters.
803 	 */
804 
805 	sql_insert_caller_info(expr, INTERNAL, -1, "%call_marker%", type_to_str(type));
806 }
807 
808 int is_recursive_member(const char *name)
809 {
810 	char buf[256];
811 	const char *p, *next;
812 	int size;
813 
814 	p = strchr(name, '>');
815 	if (!p)
816 		return 0;
817 	p++;
818 	while (true) {
819 		next = strchr(p, '>');
820 		if (!next)
821 			return 0;
822 		next++;
823 
824 		size = next - p;
825 		if (size >= sizeof(buf))
826 			return 0;
827 		memcpy(buf, p, size);
828 		buf[size] = '\0';
829 		if (strstr(next, buf))
830 			return 1;
831 		p = next;
832 	}
833 }
834 
835 char *sm_to_arg_name(struct expression *expr, struct sm_state *sm)
836 {
837 	struct symbol *sym;
838 	const char *sm_name;
839 	char *name;
840 	bool is_address = false;
841 	bool add_star = false;
842 	char buf[256];
843 	char *ret = NULL;
844 	int len;
845 
846 	expr = strip_expr(expr);
847 	if (!expr)
848 		return NULL;
849 
850 	if (expr->type == EXPR_PREOP && expr->op == '&') {
851 		expr = strip_expr(expr->unop);
852 		is_address = true;
853 	}
854 
855 	name = expr_to_var_sym(expr, &sym);
856 	if (!name || !sym)
857 		goto free;
858 	if (sym != sm->sym)
859 		goto free;
860 
861 	sm_name = sm->name;
862 	add_star = false;
863 	if (sm_name[0] == '*') {
864 		add_star = true;
865 		sm_name++;
866 	}
867 
868 	len = strlen(name);
869 	if (strncmp(name, sm_name, len) != 0)
870 		goto free;
871 	if (sm_name[len] == '\0') {
872 		snprintf(buf, sizeof(buf), "%s%s$",
873 			 add_star ? "*" : "", is_address ? "*" : "");
874 	} else {
875 		if (sm_name[len] != '.' && sm_name[len] != '-')
876 			goto free;
877 		if (sm_name[len] == '-')
878 			len++;
879 		// FIXME does is_address really imply that sm_name[len] == '-'
880 		snprintf(buf, sizeof(buf), "%s$->%s", add_star ? "*" : "",
881 			 sm_name + len);
882 	}
883 
884 	ret = alloc_sname(buf);
885 free:
886 	free_string(name);
887 	return ret;
888 }
889 
890 static void print_struct_members(struct expression *call, struct expression *expr, int param, struct stree *stree,
891 	void (*callback)(struct expression *call, int param, char *printed_name, struct sm_state *sm),
892 	bool new)
893 {
894 	struct sm_state *sm;
895 	const char *sm_name;
896 	char *name;
897 	struct symbol *sym;
898 	int len;
899 	char printed_name[256];
900 	int is_address = 0;
901 	bool add_star;
902 	struct symbol *type;
903 
904 	expr = strip_expr(expr);
905 	if (!expr)
906 		return;
907 	type = get_type(expr);
908 	if (type && type_bits(type) < type_bits(&ulong_ctype))
909 		return;
910 
911 	if (expr->type == EXPR_PREOP && expr->op == '&') {
912 		expr = strip_expr(expr->unop);
913 		is_address = 1;
914 	}
915 
916 	name = expr_to_var_sym(expr, &sym);
917 	if (!name || !sym)
918 		goto free;
919 
920 	len = strlen(name);
921 	FOR_EACH_SM(stree, sm) {
922 		if (sm->sym != sym)
923 			continue;
924 		sm_name = sm->name;
925 		add_star = false;
926 		if (sm_name[0] == '*') {
927 			add_star = true;
928 			sm_name++;
929 		}
930 		// FIXME: simplify?
931 		if (!add_star && strcmp(name, sm_name) == 0) {
932 			if (is_address) {
933 				snprintf(printed_name, sizeof(printed_name), "*$");
934 			} else {
935 				if (new)
936 					snprintf(printed_name, sizeof(printed_name), "$");
937 				else
938 					continue;
939 			}
940 		} else if (add_star && strcmp(name, sm_name) == 0) {
941 			snprintf(printed_name, sizeof(printed_name), "%s*$",
942 				 is_address ? "*" : "");
943 		} else if (strncmp(name, sm_name, len) == 0) {
944 			if (sm_name[len] != '.' && sm_name[len] != '-')
945 				continue;
946 			if (is_address && sm_name[len] == '.') {
947 				snprintf(printed_name, sizeof(printed_name),
948 					 "%s$->%s", add_star ? "*" : "",
949 					 sm_name + len + 1);
950 			} else if (is_address && sm_name[len] == '-') {
951 				snprintf(printed_name, sizeof(printed_name),
952 					 "%s(*$)%s", add_star ? "*" : "",
953 					 sm_name + len);
954 			} else {
955 				snprintf(printed_name, sizeof(printed_name),
956 					 "%s$%s", add_star ? "*" : "",
957 					 sm_name + len);
958 			}
959 		} else {
960 			continue;
961 		}
962 		if (is_recursive_member(printed_name))
963 			continue;
964 		callback(call, param, printed_name, sm);
965 	} END_FOR_EACH_SM(sm);
966 free:
967 	free_string(name);
968 }
969 
970 static void match_call_info(struct expression *call)
971 {
972 	struct member_info_callback *cb;
973 	struct expression *arg;
974 	struct stree *stree;
975 	char *name;
976 	int i;
977 
978 	name = get_fnptr_name(call->fn);
979 	if (!name)
980 		return;
981 
982 	FOR_EACH_PTR(member_callbacks, cb) {
983 		stree = get_all_states_stree(cb->owner);
984 		i = 0;
985 		FOR_EACH_PTR(call->args, arg) {
986 			print_struct_members(call, arg, i, stree, cb->callback, 0);
987 			i++;
988 		} END_FOR_EACH_PTR(arg);
989 		free_stree(&stree);
990 	} END_FOR_EACH_PTR(cb);
991 
992 	free_string(name);
993 }
994 
995 static void match_call_info_new(struct expression *call)
996 {
997 	struct member_info_callback *cb;
998 	struct expression *arg;
999 	struct stree *stree;
1000 	char *name;
1001 	int i;
1002 
1003 	name = get_fnptr_name(call->fn);
1004 	if (!name)
1005 		return;
1006 
1007 	FOR_EACH_PTR(member_callbacks_new, cb) {
1008 		stree = get_all_states_stree(cb->owner);
1009 		i = 0;
1010 		FOR_EACH_PTR(call->args, arg) {
1011 			print_struct_members(call, arg, i, stree, cb->callback, 1);
1012 			i++;
1013 		} END_FOR_EACH_PTR(arg);
1014 		free_stree(&stree);
1015 	} END_FOR_EACH_PTR(cb);
1016 
1017 	free_string(name);
1018 }
1019 
1020 static int get_param(int param, char **name, struct symbol **sym)
1021 {
1022 	struct symbol *arg;
1023 	int i;
1024 
1025 	i = 0;
1026 	FOR_EACH_PTR(cur_func_sym->ctype.base_type->arguments, arg) {
1027 		/*
1028 		 * this is a temporary hack to work around a bug (I think in sparse?)
1029 		 * 2.6.37-rc1:fs/reiserfs/journal.o
1030 		 * If there is a function definition without parameter name found
1031 		 * after a function implementation then it causes a crash.
1032 		 * int foo() {}
1033 		 * int bar(char *);
1034 		 */
1035 		if (arg->ident->name < (char *)100)
1036 			continue;
1037 		if (i == param) {
1038 			*name = arg->ident->name;
1039 			*sym = arg;
1040 			return TRUE;
1041 		}
1042 		i++;
1043 	} END_FOR_EACH_PTR(arg);
1044 
1045 	return FALSE;
1046 }
1047 
1048 static int function_signature_matches(const char *sig)
1049 {
1050 	char *my_sig;
1051 
1052 	my_sig = function_signature();
1053 	if (!sig || !my_sig)
1054 		return 1;  /* default to matching */
1055 	if (strcmp(my_sig, sig) == 0)
1056 		  return 1;
1057 	return 0;
1058 }
1059 
1060 static int caller_info_callback(void *_data, int argc, char **argv, char **azColName)
1061 {
1062 	struct select_caller_info_data *data = _data;
1063 	int func_id;
1064 	long type;
1065 	long param;
1066 	char *key;
1067 	char *value;
1068 	char *name = NULL;
1069 	struct symbol *sym = NULL;
1070 	struct def_callback *def_callback;
1071 	struct stree *stree;
1072 	struct timeval cur_time;
1073 
1074 	data->results = 1;
1075 
1076 	if (argc != 5)
1077 		return 0;
1078 
1079 	gettimeofday(&cur_time, NULL);
1080 	if (cur_time.tv_sec - data->start_time.tv_sec > 10)
1081 		return 0;
1082 
1083 	func_id = atoi(argv[0]);
1084 	errno = 0;
1085 	type = strtol(argv[1], NULL, 10);
1086 	param = strtol(argv[2], NULL, 10);
1087 	if (errno)
1088 		return 0;
1089 	key = argv[3];
1090 	value = argv[4];
1091 
1092 	if (data->prev_func_id == -1)
1093 		data->prev_func_id = func_id;
1094 	if (func_id != data->prev_func_id) {
1095 		stree = __pop_fake_cur_stree();
1096 		if (!data->ignore)
1097 			merge_stree(&data->final_states, stree);
1098 		free_stree(&stree);
1099 		__push_fake_cur_stree();
1100 		__unnullify_path();
1101 		data->prev_func_id = func_id;
1102 		data->ignore = 0;
1103 	}
1104 
1105 	if (data->ignore)
1106 		return 0;
1107 	if (type == INTERNAL &&
1108 	    !function_signature_matches(value)) {
1109 		data->ignore = 1;
1110 		return 0;
1111 	}
1112 
1113 	if (param >= 0 && !get_param(param, &name, &sym))
1114 		return 0;
1115 
1116 	FOR_EACH_PTR(select_caller_info_callbacks, def_callback) {
1117 		if (def_callback->hook_type == type)
1118 			def_callback->callback(name, sym, key, value);
1119 	} END_FOR_EACH_PTR(def_callback);
1120 
1121 	return 0;
1122 }
1123 
1124 static struct string_list *ptr_names_done;
1125 static struct string_list *ptr_names;
1126 
1127 static int get_ptr_name(void *unused, int argc, char **argv, char **azColName)
1128 {
1129 	insert_string(&ptr_names, alloc_string(argv[0]));
1130 	return 0;
1131 }
1132 
1133 static char *get_next_ptr_name(void)
1134 {
1135 	char *ptr;
1136 
1137 	FOR_EACH_PTR(ptr_names, ptr) {
1138 		if (!insert_string(&ptr_names_done, ptr))
1139 			continue;
1140 		return ptr;
1141 	} END_FOR_EACH_PTR(ptr);
1142 	return NULL;
1143 }
1144 
1145 static void get_ptr_names(const char *file, const char *name)
1146 {
1147 	char sql_filter[1024];
1148 	int before, after;
1149 
1150 	if (file) {
1151 		snprintf(sql_filter, 1024, "file = '%s' and function = '%s';",
1152 			 file, name);
1153 	} else {
1154 		snprintf(sql_filter, 1024, "function = '%s';", name);
1155 	}
1156 
1157 	before = ptr_list_size((struct ptr_list *)ptr_names);
1158 
1159 	run_sql(get_ptr_name, NULL,
1160 		"select distinct ptr from function_ptr where %s",
1161 		sql_filter);
1162 
1163 	after = ptr_list_size((struct ptr_list *)ptr_names);
1164 	if (before == after)
1165 		return;
1166 
1167 	while ((name = get_next_ptr_name()))
1168 		get_ptr_names(NULL, name);
1169 }
1170 
1171 static void match_data_from_db(struct symbol *sym)
1172 {
1173 	struct select_caller_info_data data = { .prev_func_id = -1 };
1174 	struct sm_state *sm;
1175 	struct stree *stree;
1176 	struct timeval end_time;
1177 
1178 	if (!sym || !sym->ident)
1179 		return;
1180 
1181 	set_fn_mtag(sym);
1182 	gettimeofday(&data.start_time, NULL);
1183 
1184 	__push_fake_cur_stree();
1185 	__unnullify_path();
1186 
1187 	if (!__inline_fn) {
1188 		char *ptr;
1189 
1190 		if (sym->ctype.modifiers & MOD_STATIC)
1191 			get_ptr_names(get_base_file(), sym->ident->name);
1192 		else
1193 			get_ptr_names(NULL, sym->ident->name);
1194 
1195 		if (ptr_list_size((struct ptr_list *)ptr_names) > 20) {
1196 			__free_ptr_list((struct ptr_list **)&ptr_names);
1197 			__free_ptr_list((struct ptr_list **)&ptr_names_done);
1198 			__free_fake_cur_stree();
1199 			return;
1200 		}
1201 
1202 		sql_select_caller_info(&data,
1203 				       "call_id, type, parameter, key, value",
1204 				       sym);
1205 
1206 
1207 		stree = __pop_fake_cur_stree();
1208 		if (!data.ignore)
1209 			merge_stree(&data.final_states, stree);
1210 		free_stree(&stree);
1211 		__push_fake_cur_stree();
1212 		__unnullify_path();
1213 		data.prev_func_id = -1;
1214 		data.ignore = 0;
1215 		data.results = 0;
1216 
1217 		FOR_EACH_PTR(ptr_names, ptr) {
1218 			run_sql(caller_info_callback, &data,
1219 				"select call_id, type, parameter, key, value"
1220 				" from common_caller_info where function = '%s' order by call_id",
1221 				ptr);
1222 		} END_FOR_EACH_PTR(ptr);
1223 
1224 		if (data.results) {
1225 			FOR_EACH_PTR(ptr_names, ptr) {
1226 				free_string(ptr);
1227 			} END_FOR_EACH_PTR(ptr);
1228 			goto free_ptr_names;
1229 		}
1230 
1231 		FOR_EACH_PTR(ptr_names, ptr) {
1232 			run_sql(caller_info_callback, &data,
1233 				"select call_id, type, parameter, key, value"
1234 				" from caller_info where function = '%s' order by call_id",
1235 				ptr);
1236 			free_string(ptr);
1237 		} END_FOR_EACH_PTR(ptr);
1238 
1239 free_ptr_names:
1240 		__free_ptr_list((struct ptr_list **)&ptr_names);
1241 		__free_ptr_list((struct ptr_list **)&ptr_names_done);
1242 	} else {
1243 		sql_select_caller_info(&data,
1244 				       "call_id, type, parameter, key, value",
1245 				       sym);
1246 	}
1247 
1248 	stree = __pop_fake_cur_stree();
1249 	if (!data.ignore)
1250 		merge_stree(&data.final_states, stree);
1251 	free_stree(&stree);
1252 
1253 	gettimeofday(&end_time, NULL);
1254 	if (end_time.tv_sec - data.start_time.tv_sec <= 10) {
1255 		FOR_EACH_SM(data.final_states, sm) {
1256 			__set_sm(sm);
1257 		} END_FOR_EACH_SM(sm);
1258 	}
1259 
1260 	free_stree(&data.final_states);
1261 }
1262 
1263 static int return_implies_callbacks(void *_info, int argc, char **argv, char **azColName)
1264 {
1265 	struct implies_info *info = _info;
1266 	struct db_implies_callback *cb;
1267 	struct expression *arg = NULL;
1268 	int type;
1269 	int param;
1270 
1271 	if (argc != 5)
1272 		return 0;
1273 
1274 	type = atoi(argv[1]);
1275 	param = atoi(argv[2]);
1276 
1277 	FOR_EACH_PTR(info->cb_list, cb) {
1278 		if (cb->type != type)
1279 			continue;
1280 		if (param != -1) {
1281 			arg = get_argument_from_call_expr(info->expr->args, param);
1282 			if (!arg)
1283 				continue;
1284 		}
1285 		cb->callback(info->expr, arg, argv[3], argv[4]);
1286 	} END_FOR_EACH_PTR(cb);
1287 
1288 	return 0;
1289 }
1290 
1291 static int call_implies_callbacks(void *_info, int argc, char **argv, char **azColName)
1292 {
1293 	struct implies_info *info = _info;
1294 	struct db_implies_callback *cb;
1295 	struct expression *arg;
1296 	struct symbol *sym;
1297 	char *name;
1298 	int type;
1299 	int param;
1300 
1301 	if (argc != 5)
1302 		return 0;
1303 
1304 	type = atoi(argv[1]);
1305 	param = atoi(argv[2]);
1306 
1307 	if (!get_param(param, &name, &sym))
1308 		return 0;
1309 	arg = symbol_expression(sym);
1310 	if (!arg)
1311 		return 0;
1312 
1313 	FOR_EACH_PTR(info->cb_list, cb) {
1314 		if (cb->type != type)
1315 			continue;
1316 		cb->callback(info->expr, arg, argv[3], argv[4]);
1317 	} END_FOR_EACH_PTR(cb);
1318 
1319 	return 0;
1320 }
1321 
1322 static void match_return_implies(struct expression *expr)
1323 {
1324 	struct implies_info info = {
1325 		.type = RETURN_IMPLIES,
1326 		.cb_list = return_implies_cb_list,
1327 	};
1328 
1329 	if (expr->fn->type != EXPR_SYMBOL ||
1330 	    !expr->fn->symbol)
1331 		return;
1332 	info.expr = expr;
1333 	info.sym = expr->fn->symbol;
1334 	sql_select_implies("function, type, parameter, key, value", &info,
1335 			   return_implies_callbacks);
1336 }
1337 
1338 static void match_call_implies(struct symbol *sym)
1339 {
1340 	struct implies_info info = {
1341 		.type = CALL_IMPLIES,
1342 		.cb_list = call_implies_cb_list,
1343 	};
1344 
1345 	if (!sym || !sym->ident)
1346 		return;
1347 
1348 	info.sym = sym;
1349 	sql_select_implies("function, type, parameter, key, value", &info,
1350 			   call_implies_callbacks);
1351 }
1352 
1353 static char *get_fn_param_str(struct expression *expr)
1354 {
1355 	struct expression *tmp;
1356 	int param;
1357 	char buf[32];
1358 
1359 	tmp = get_assigned_expr(expr);
1360 	if (tmp)
1361 		expr = tmp;
1362 	expr = strip_expr(expr);
1363 	if (!expr || expr->type != EXPR_CALL)
1364 		return NULL;
1365 	expr = strip_expr(expr->fn);
1366 	if (!expr || expr->type != EXPR_SYMBOL)
1367 		return NULL;
1368 	param = get_param_num(expr);
1369 	if (param < 0)
1370 		return NULL;
1371 
1372 	snprintf(buf, sizeof(buf), "[r $%d]", param);
1373 	return alloc_sname(buf);
1374 }
1375 
1376 static char *get_return_compare_is_param(struct expression *expr)
1377 {
1378 	char *var;
1379 	char buf[256];
1380 	int comparison;
1381 	int param;
1382 
1383 	param = get_param_num(expr);
1384 	if (param < 0)
1385 		return NULL;
1386 
1387 	var = expr_to_var(expr);
1388 	if (!var)
1389 		return NULL;
1390 	snprintf(buf, sizeof(buf), "%s orig", var);
1391 	comparison = get_comparison_strings(var, buf);
1392 	free_string(var);
1393 
1394 	if (!comparison)
1395 		return NULL;
1396 
1397 	snprintf(buf, sizeof(buf), "[%s$%d]", show_special(comparison), param);
1398 	return alloc_sname(buf);
1399 }
1400 
1401 static char *get_return_compare_str(struct expression *expr)
1402 {
1403 	char *compare_str;
1404 
1405 	compare_str = get_return_compare_is_param(expr);
1406 	if (compare_str)
1407 		return compare_str;
1408 
1409 	compare_str = expr_lte_to_param(expr, -1);
1410 	if (compare_str)
1411 		return compare_str;
1412 
1413 	return expr_param_comparison(expr, -1);
1414 }
1415 
1416 static const char *get_return_ranges_str(struct expression *expr, struct range_list **rl_p)
1417 {
1418 	struct range_list *rl;
1419 	char *return_ranges;
1420 	sval_t sval;
1421 	char *fn_param_str;
1422 	char *compare_str;
1423 	char *math_str;
1424 	char buf[128];
1425 
1426 	*rl_p = NULL;
1427 
1428 	if (!expr)
1429 		return alloc_sname("");
1430 
1431 	if (get_implied_value(expr, &sval)) {
1432 		sval = sval_cast(cur_func_return_type(), sval);
1433 		*rl_p = alloc_rl(sval, sval);
1434 		return sval_to_str_or_err_ptr(sval);
1435 	}
1436 
1437 	fn_param_str = get_fn_param_str(expr);
1438 	compare_str = expr_equal_to_param(expr, -1);
1439 	math_str = get_value_in_terms_of_parameter_math(expr);
1440 
1441 	if (get_implied_rl(expr, &rl) && !is_whole_rl(rl)) {
1442 		rl = cast_rl(cur_func_return_type(), rl);
1443 		return_ranges = show_rl(rl);
1444 	} else if (get_imaginary_absolute(expr, &rl)){
1445 		rl = cast_rl(cur_func_return_type(), rl);
1446 		return alloc_sname(show_rl(rl));
1447 	} else {
1448 		get_absolute_rl(expr, &rl);
1449 		rl = cast_rl(cur_func_return_type(), rl);
1450 		return_ranges = show_rl(rl);
1451 	}
1452 	*rl_p = rl;
1453 
1454 	if (fn_param_str) {
1455 		snprintf(buf, sizeof(buf), "%s%s", return_ranges, fn_param_str);
1456 		return alloc_sname(buf);
1457 	}
1458 	if (compare_str) {
1459 		snprintf(buf, sizeof(buf), "%s%s", return_ranges, compare_str);
1460 		return alloc_sname(buf);
1461 	}
1462 	if (math_str) {
1463 		snprintf(buf, sizeof(buf), "%s[%s]", return_ranges, math_str);
1464 		return alloc_sname(buf);
1465 	}
1466 	compare_str = get_return_compare_str(expr);
1467 	if (compare_str) {
1468 		snprintf(buf, sizeof(buf), "%s%s", return_ranges, compare_str);
1469 		return alloc_sname(buf);
1470 	}
1471 
1472 	return return_ranges;
1473 }
1474 
1475 static void match_return_info(int return_id, char *return_ranges, struct expression *expr)
1476 {
1477 	sql_insert_return_states(return_id, return_ranges, INTERNAL, -1, "", function_signature());
1478 }
1479 
1480 static bool call_return_state_hooks_conditional(struct expression *expr)
1481 {
1482 	int final_pass_orig = final_pass;
1483 	static int recurse;
1484 
1485 	if (recurse >= 2)
1486 		return false;
1487 	if (!expr ||
1488 	    (expr->type != EXPR_CONDITIONAL && expr->type != EXPR_SELECT))
1489 		return false;
1490 
1491 	recurse++;
1492 
1493 	__push_fake_cur_stree();
1494 
1495 	final_pass = 0;
1496 	__split_whole_condition(expr->conditional);
1497 	final_pass = final_pass_orig;
1498 
1499 	call_return_state_hooks(expr->cond_true ?: expr->conditional);
1500 
1501 	__push_true_states();
1502 	__use_false_states();
1503 
1504 	call_return_state_hooks(expr->cond_false);
1505 
1506 	__merge_true_states();
1507 	__free_fake_cur_stree();
1508 
1509 	recurse--;
1510 	return true;
1511 }
1512 
1513 static void call_return_state_hooks_compare(struct expression *expr)
1514 {
1515 	struct returned_state_callback *cb;
1516 	char *return_ranges;
1517 	int final_pass_orig = final_pass;
1518 	sval_t sval = { .type = &int_ctype };
1519 	sval_t ret;
1520 
1521 	if (!get_implied_value(expr, &ret))
1522 		ret.value = -1;
1523 
1524 	__push_fake_cur_stree();
1525 
1526 	final_pass = 0;
1527 	__split_whole_condition(expr);
1528 	final_pass = final_pass_orig;
1529 
1530 	if (ret.value != 0) {
1531 		return_ranges = alloc_sname("1");
1532 		sval.value = 1;
1533 		set_state(RETURN_ID, "return_ranges", NULL, alloc_estate_sval(sval));
1534 
1535 		return_id++;
1536 		FOR_EACH_PTR(returned_state_callbacks, cb) {
1537 			cb->callback(return_id, return_ranges, expr);
1538 		} END_FOR_EACH_PTR(cb);
1539 	}
1540 
1541 	__push_true_states();
1542 	__use_false_states();
1543 
1544 	if (ret.value != 1) {
1545 		return_ranges = alloc_sname("0");
1546 		sval.value = 0;
1547 		set_state(RETURN_ID, "return_ranges", NULL, alloc_estate_sval(sval));
1548 
1549 		return_id++;
1550 		FOR_EACH_PTR(returned_state_callbacks, cb) {
1551 			cb->callback(return_id, return_ranges, expr);
1552 		} END_FOR_EACH_PTR(cb);
1553 	}
1554 
1555 	__merge_true_states();
1556 	__free_fake_cur_stree();
1557 }
1558 
1559 static int ptr_in_list(struct sm_state *sm, struct state_list *slist)
1560 {
1561 	struct sm_state *tmp;
1562 
1563 	FOR_EACH_PTR(slist, tmp) {
1564 		if (strcmp(tmp->state->name, sm->state->name) == 0)
1565 			return 1;
1566 	} END_FOR_EACH_PTR(tmp);
1567 
1568 	return 0;
1569 }
1570 
1571 static int split_possible_helper(struct sm_state *sm, struct expression *expr)
1572 {
1573 	struct returned_state_callback *cb;
1574 	struct range_list *rl;
1575 	char *return_ranges;
1576 	struct sm_state *tmp;
1577 	int ret = 0;
1578 	int nr_possible, nr_states;
1579 	char *compare_str;
1580 	char buf[128];
1581 	struct state_list *already_handled = NULL;
1582 	sval_t sval;
1583 
1584 	if (!sm || !sm->merged)
1585 		return 0;
1586 
1587 	if (too_many_possible(sm))
1588 		return 0;
1589 
1590 	/* bail if it gets too complicated */
1591 	nr_possible = 0;
1592 	FOR_EACH_PTR(sm->possible, tmp) {
1593 		if (tmp->merged)
1594 			continue;
1595 		if (ptr_in_list(tmp, already_handled))
1596 			continue;
1597 		add_ptr_list(&already_handled, tmp);
1598 		nr_possible++;
1599 	} END_FOR_EACH_PTR(tmp);
1600 	free_slist(&already_handled);
1601 	nr_states = get_db_state_count();
1602 	if (nr_states * nr_possible >= 2000)
1603 		return 0;
1604 
1605 	FOR_EACH_PTR(sm->possible, tmp) {
1606 		if (tmp->merged)
1607 			continue;
1608 		if (ptr_in_list(tmp, already_handled))
1609 			continue;
1610 		add_ptr_list(&already_handled, tmp);
1611 
1612 		ret = 1;
1613 		__push_fake_cur_stree();
1614 
1615 		overwrite_states_using_pool(sm, tmp);
1616 
1617 		rl = cast_rl(cur_func_return_type(), estate_rl(tmp->state));
1618 		return_ranges = show_rl(rl);
1619 		set_state(RETURN_ID, "return_ranges", NULL, alloc_estate_rl(clone_rl(rl)));
1620 		if (!rl_to_sval(rl, &sval)) {
1621 			compare_str = get_return_compare_str(expr);
1622 			if (compare_str) {
1623 				snprintf(buf, sizeof(buf), "%s%s", return_ranges, compare_str);
1624 				return_ranges = alloc_sname(buf);
1625 			}
1626 		}
1627 
1628 		return_id++;
1629 		FOR_EACH_PTR(returned_state_callbacks, cb) {
1630 			cb->callback(return_id, return_ranges, expr);
1631 		} END_FOR_EACH_PTR(cb);
1632 
1633 		__free_fake_cur_stree();
1634 	} END_FOR_EACH_PTR(tmp);
1635 
1636 	free_slist(&already_handled);
1637 
1638 	return ret;
1639 }
1640 
1641 static int call_return_state_hooks_split_possible(struct expression *expr)
1642 {
1643 	struct sm_state *sm;
1644 
1645 	if (!expr)
1646 		return 0;
1647 
1648 	sm = get_sm_state_expr(SMATCH_EXTRA, expr);
1649 	return split_possible_helper(sm, expr);
1650 }
1651 
1652 static bool has_possible_negative(struct sm_state *sm)
1653 {
1654 	struct sm_state *tmp;
1655 
1656 	if (!type_signed(estate_type(sm->state)))
1657 		return false;
1658 
1659 	FOR_EACH_PTR(sm->possible, tmp) {
1660 		if (!estate_rl(tmp->state))
1661 			continue;
1662 		if (sval_is_negative(estate_min(tmp->state)) &&
1663 		    sval_is_negative(estate_max(tmp->state)))
1664 			return true;
1665 	} END_FOR_EACH_PTR(tmp);
1666 
1667 	return false;
1668 }
1669 
1670 static bool has_separate_zero_null(struct sm_state *sm)
1671 {
1672 	struct sm_state *tmp;
1673 	sval_t sval;
1674 
1675 	FOR_EACH_PTR(sm->possible, tmp) {
1676 		if (!estate_get_single_value(tmp->state, &sval))
1677 			continue;
1678 		if (sval.value == 0)
1679 			return true;
1680 	} END_FOR_EACH_PTR(tmp);
1681 
1682 	return false;
1683 }
1684 
1685 static int split_positive_from_negative(struct expression *expr)
1686 {
1687 	struct sm_state *sm;
1688 	struct returned_state_callback *cb;
1689 	struct range_list *rl;
1690 	const char *return_ranges;
1691 	struct range_list *ret_rl;
1692 	bool separate_zero;
1693 	int undo;
1694 
1695 	/* We're going to print the states 3 times */
1696 	if (get_db_state_count() > 10000 / 3)
1697 		return 0;
1698 
1699 	if (!get_implied_rl(expr, &rl) || !rl)
1700 		return 0;
1701 	/* Forget about INT_MAX and larger */
1702 	if (rl_max(rl).value <= 0)
1703 		return 0;
1704 	if (!sval_is_negative(rl_min(rl)))
1705 		return 0;
1706 
1707 	sm = get_sm_state_expr(SMATCH_EXTRA, expr);
1708 	if (!sm)
1709 		return 0;
1710 	if (!has_possible_negative(sm))
1711 		return 0;
1712 	separate_zero = has_separate_zero_null(sm);
1713 
1714 	if (!assume(compare_expression(expr, separate_zero ? '>' : SPECIAL_GTE, zero_expr())))
1715 		return 0;
1716 
1717 	return_id++;
1718 	return_ranges = get_return_ranges_str(expr, &ret_rl);
1719 	set_state(RETURN_ID, "return_ranges", NULL, alloc_estate_rl(ret_rl));
1720 	FOR_EACH_PTR(returned_state_callbacks, cb) {
1721 		cb->callback(return_id, (char *)return_ranges, expr);
1722 	} END_FOR_EACH_PTR(cb);
1723 
1724 	end_assume();
1725 
1726 	if (separate_zero) {
1727 		undo = assume(compare_expression(expr, SPECIAL_EQUAL, zero_expr()));
1728 
1729 		return_id++;
1730 		return_ranges = get_return_ranges_str(expr, &ret_rl);
1731 		set_state(RETURN_ID, "return_ranges", NULL, alloc_estate_rl(ret_rl));
1732 		FOR_EACH_PTR(returned_state_callbacks, cb) {
1733 			cb->callback(return_id, (char *)return_ranges, expr);
1734 		} END_FOR_EACH_PTR(cb);
1735 
1736 		if (undo)
1737 			end_assume();
1738 	}
1739 
1740 	undo = assume(compare_expression(expr, '<', zero_expr()));
1741 
1742 	return_id++;
1743 	return_ranges = get_return_ranges_str(expr, &ret_rl);
1744 	set_state(RETURN_ID, "return_ranges", NULL, alloc_estate_rl(ret_rl));
1745 	FOR_EACH_PTR(returned_state_callbacks, cb) {
1746 		cb->callback(return_id, (char *)return_ranges, expr);
1747 	} END_FOR_EACH_PTR(cb);
1748 
1749 	if (undo)
1750 		end_assume();
1751 
1752 	return 1;
1753 }
1754 
1755 static int call_return_state_hooks_split_null_non_null_zero(struct expression *expr)
1756 {
1757 	struct returned_state_callback *cb;
1758 	struct range_list *rl;
1759 	struct range_list *nonnull_rl;
1760 	sval_t null_sval;
1761 	struct range_list *null_rl = NULL;
1762 	char *return_ranges;
1763 	struct sm_state *sm;
1764 	struct smatch_state *state;
1765 	int nr_states;
1766 	int final_pass_orig = final_pass;
1767 
1768 	if (!expr || expr_equal_to_param(expr, -1))
1769 		return 0;
1770 	if (expr->type == EXPR_CALL)
1771 		return 0;
1772 
1773 	sm = get_sm_state_expr(SMATCH_EXTRA, expr);
1774 	if (!sm)
1775 		return 0;
1776 	if (ptr_list_size((struct ptr_list *)sm->possible) == 1)
1777 		return 0;
1778 	state = sm->state;
1779 	if (!estate_rl(state))
1780 		return 0;
1781 	if (estate_min(state).value == 0 && estate_max(state).value == 0)
1782 		return 0;
1783 	if (has_possible_negative(sm))
1784 		return 0;
1785 	if (!has_separate_zero_null(sm))
1786 		return 0;
1787 
1788 	nr_states = get_db_state_count();
1789 	if (option_info && nr_states >= 1500)
1790 		return 0;
1791 
1792 	rl = estate_rl(state);
1793 
1794 	__push_fake_cur_stree();
1795 
1796 	final_pass = 0;
1797 	__split_whole_condition(expr);
1798 	final_pass = final_pass_orig;
1799 
1800 	nonnull_rl = rl_filter(rl, rl_zero());
1801 	return_ranges = show_rl(nonnull_rl);
1802 	set_state(RETURN_ID, "return_ranges", NULL, alloc_estate_rl(nonnull_rl));
1803 
1804 	return_id++;
1805 	FOR_EACH_PTR(returned_state_callbacks, cb) {
1806 		cb->callback(return_id, return_ranges, expr);
1807 	} END_FOR_EACH_PTR(cb);
1808 
1809 	__push_true_states();
1810 	__use_false_states();
1811 
1812 	return_ranges = alloc_sname("0");
1813 	null_sval = sval_type_val(rl_type(rl), 0);
1814 	add_range(&null_rl, null_sval, null_sval);
1815 	set_state(RETURN_ID, "return_ranges", NULL, alloc_estate_rl(null_rl));
1816 	return_id++;
1817 	FOR_EACH_PTR(returned_state_callbacks, cb) {
1818 		cb->callback(return_id, return_ranges, expr);
1819 	} END_FOR_EACH_PTR(cb);
1820 
1821 	__merge_true_states();
1822 	__free_fake_cur_stree();
1823 
1824 	return 1;
1825 }
1826 
1827 static bool is_kernel_success_fail(struct sm_state *sm)
1828 {
1829 	struct sm_state *tmp;
1830 	struct range_list *rl;
1831 	bool has_zero = false;
1832 	bool has_neg = false;
1833 
1834 	if (!type_signed(estate_type(sm->state)))
1835 		return false;
1836 
1837 	FOR_EACH_PTR(sm->possible, tmp) {
1838 		rl = estate_rl(tmp->state);
1839 		if (!rl)
1840 			return false;
1841 		if (rl_min(rl).value == 0 && rl_max(rl).value == 0) {
1842 			has_zero = true;
1843 			continue;
1844 		}
1845 		has_neg = true;
1846 		if (rl_min(rl).value >= -4095 && rl_max(rl).value < 0)
1847 			continue;
1848 		if (strcmp(tmp->state->name, "s32min-(-1)") == 0)
1849 			continue;
1850 		if (strcmp(tmp->state->name, "s32min-(-1),1-s32max") == 0)
1851 			continue;
1852 		return false;
1853 	} END_FOR_EACH_PTR(tmp);
1854 
1855 	return has_zero && has_neg;
1856 }
1857 
1858 static int call_return_state_hooks_split_success_fail(struct expression *expr)
1859 {
1860 	struct sm_state *sm;
1861 	struct range_list *rl;
1862 	struct range_list *nonzero_rl;
1863 	sval_t zero_sval;
1864 	struct range_list *zero_rl = NULL;
1865 	int nr_states;
1866 	struct returned_state_callback *cb;
1867 	char *return_ranges;
1868 	int final_pass_orig = final_pass;
1869 
1870 	if (option_project != PROJ_KERNEL)
1871 		return 0;
1872 
1873 	nr_states = get_db_state_count();
1874 	if (nr_states > 2000)
1875 		return 0;
1876 
1877 	sm = get_sm_state_expr(SMATCH_EXTRA, expr);
1878 	if (!sm)
1879 		return 0;
1880 	if (ptr_list_size((struct ptr_list *)sm->possible) == 1)
1881 		return 0;
1882 	if (!is_kernel_success_fail(sm))
1883 		return 0;
1884 
1885 	rl = estate_rl(sm->state);
1886 	if (!rl)
1887 		return 0;
1888 
1889 	__push_fake_cur_stree();
1890 
1891 	final_pass = 0;
1892 	__split_whole_condition(expr);
1893 	final_pass = final_pass_orig;
1894 
1895 	nonzero_rl = rl_filter(rl, rl_zero());
1896 	nonzero_rl = cast_rl(cur_func_return_type(), nonzero_rl);
1897 	return_ranges = show_rl(nonzero_rl);
1898 	set_state(RETURN_ID, "return_ranges", NULL, alloc_estate_rl(nonzero_rl));
1899 
1900 	return_id++;
1901 	FOR_EACH_PTR(returned_state_callbacks, cb) {
1902 		cb->callback(return_id, return_ranges, expr);
1903 	} END_FOR_EACH_PTR(cb);
1904 
1905 	__push_true_states();
1906 	__use_false_states();
1907 
1908 	return_ranges = alloc_sname("0");
1909 	zero_sval = sval_type_val(rl_type(rl), 0);
1910 	add_range(&zero_rl, zero_sval, zero_sval);
1911 	set_state(RETURN_ID, "return_ranges", NULL, alloc_estate_rl(zero_rl));
1912 	return_id++;
1913 	FOR_EACH_PTR(returned_state_callbacks, cb) {
1914 		cb->callback(return_id, return_ranges, expr);
1915 	} END_FOR_EACH_PTR(cb);
1916 
1917 	__merge_true_states();
1918 	__free_fake_cur_stree();
1919 
1920 	return 1;
1921 }
1922 
1923 static int is_boolean(struct expression *expr)
1924 {
1925 	struct range_list *rl;
1926 
1927 	if (!get_implied_rl(expr, &rl))
1928 		return 0;
1929 	if (rl_min(rl).value == 0 && rl_max(rl).value == 1)
1930 		return 1;
1931 	return 0;
1932 }
1933 
1934 static int splitable_function_call(struct expression *expr)
1935 {
1936 	struct sm_state *sm;
1937 	char buf[64];
1938 
1939 	if (!expr || expr->type != EXPR_CALL)
1940 		return 0;
1941 	snprintf(buf, sizeof(buf), "return %p", expr);
1942 	sm = get_sm_state(SMATCH_EXTRA, buf, NULL);
1943 	return split_possible_helper(sm, expr);
1944 }
1945 
1946 static struct sm_state *find_bool_param(void)
1947 {
1948 	struct stree *start_states;
1949 	struct symbol *arg;
1950 	struct sm_state *sm, *tmp;
1951 	sval_t sval;
1952 
1953 	start_states = get_start_states();
1954 
1955 	FOR_EACH_PTR_REVERSE(cur_func_sym->ctype.base_type->arguments, arg) {
1956 		if (!arg->ident)
1957 			continue;
1958 		sm = get_sm_state_stree(start_states, SMATCH_EXTRA, arg->ident->name, arg);
1959 		if (!sm)
1960 			continue;
1961 		if (rl_min(estate_rl(sm->state)).value != 0 ||
1962 		    rl_max(estate_rl(sm->state)).value != 1)
1963 			continue;
1964 		goto found;
1965 	} END_FOR_EACH_PTR_REVERSE(arg);
1966 
1967 	return NULL;
1968 
1969 found:
1970 	/*
1971 	 * Check if it's splitable.  If not, then splitting it up is likely not
1972 	 * useful for the callers.
1973 	 */
1974 	FOR_EACH_PTR(sm->possible, tmp) {
1975 		if (is_merged(tmp))
1976 			continue;
1977 		if (!estate_get_single_value(tmp->state, &sval))
1978 			return NULL;
1979 	} END_FOR_EACH_PTR(tmp);
1980 
1981 	return sm;
1982 }
1983 
1984 static int split_on_bool_sm(struct sm_state *sm, struct expression *expr)
1985 {
1986 	struct returned_state_callback *cb;
1987 	struct range_list *ret_rl;
1988 	const char *return_ranges;
1989 	struct sm_state *tmp;
1990 	int ret = 0;
1991 	struct state_list *already_handled = NULL;
1992 
1993 	if (!sm || !sm->merged)
1994 		return 0;
1995 
1996 	if (too_many_possible(sm))
1997 		return 0;
1998 
1999 	FOR_EACH_PTR(sm->possible, tmp) {
2000 		if (tmp->merged)
2001 			continue;
2002 		if (ptr_in_list(tmp, already_handled))
2003 			continue;
2004 		add_ptr_list(&already_handled, tmp);
2005 
2006 		ret = 1;
2007 		__push_fake_cur_stree();
2008 
2009 		overwrite_states_using_pool(sm, tmp);
2010 
2011 		return_ranges = get_return_ranges_str(expr, &ret_rl);
2012 		set_state(RETURN_ID, "return_ranges", NULL, alloc_estate_rl(ret_rl));
2013 		return_id++;
2014 		FOR_EACH_PTR(returned_state_callbacks, cb) {
2015 			cb->callback(return_id, (char *)return_ranges, expr);
2016 		} END_FOR_EACH_PTR(cb);
2017 
2018 		__free_fake_cur_stree();
2019 	} END_FOR_EACH_PTR(tmp);
2020 
2021 	free_slist(&already_handled);
2022 
2023 	return ret;
2024 }
2025 
2026 static int split_by_bool_param(struct expression *expr)
2027 {
2028 	struct sm_state *start_sm, *sm;
2029 	sval_t sval;
2030 
2031 	start_sm = find_bool_param();
2032 	if (!start_sm)
2033 		return 0;
2034 	sm = get_sm_state(SMATCH_EXTRA, start_sm->name, start_sm->sym);
2035 	if (!sm || estate_get_single_value(sm->state, &sval))
2036 		return 0;
2037 
2038 	if (get_db_state_count() * 2 >= 2000)
2039 		return 0;
2040 
2041 	return split_on_bool_sm(sm, expr);
2042 }
2043 
2044 static int split_by_null_nonnull_param(struct expression *expr)
2045 {
2046 	struct symbol *arg;
2047 	struct sm_state *sm;
2048 	int nr_possible;
2049 
2050 	/* function must only take one pointer */
2051 	if (ptr_list_size((struct ptr_list *)cur_func_sym->ctype.base_type->arguments) != 1)
2052 		return 0;
2053 	arg = first_ptr_list((struct ptr_list *)cur_func_sym->ctype.base_type->arguments);
2054 	if (!arg->ident)
2055 		return 0;
2056 	if (get_real_base_type(arg)->type != SYM_PTR)
2057 		return 0;
2058 
2059 	if (param_was_set_var_sym(arg->ident->name, arg))
2060 		return 0;
2061 	sm = get_sm_state(SMATCH_EXTRA, arg->ident->name, arg);
2062 	if (!sm)
2063 		return 0;
2064 
2065 	if (!has_separate_zero_null(sm))
2066 		return 0;
2067 
2068 	nr_possible = ptr_list_size((struct ptr_list *)sm->possible);
2069 	if (get_db_state_count() * nr_possible >= 2000)
2070 		return 0;
2071 
2072 	return split_on_bool_sm(sm, expr);
2073 }
2074 
2075 struct expression *strip_expr_statement(struct expression *expr)
2076 {
2077 	struct expression *orig = expr;
2078 	struct statement *stmt, *last_stmt;
2079 
2080 	if (!expr)
2081 		return NULL;
2082 	if (expr->type == EXPR_PREOP && expr->op == '(')
2083 		expr = expr->unop;
2084 	if (expr->type != EXPR_STATEMENT)
2085 		return orig;
2086 	stmt = expr->statement;
2087 	if (!stmt || stmt->type != STMT_COMPOUND)
2088 		return orig;
2089 
2090 	last_stmt = last_ptr_list((struct ptr_list *)stmt->stmts);
2091 	if (!last_stmt || last_stmt->type == STMT_LABEL)
2092 		last_stmt = last_stmt->label_statement;
2093 	if (!last_stmt || last_stmt->type != STMT_EXPRESSION)
2094 		return orig;
2095 	return strip_expr(last_stmt->expression);
2096 }
2097 
2098 static bool is_kernel_error_path(struct expression *expr)
2099 {
2100 	struct range_list *rl;
2101 
2102 	/*
2103 	 * Splitting up returns requires resources.  It also requires resources
2104 	 * for the caller.  It doesn't seem worth it to split anything up.
2105 	 */
2106 	if (!get_implied_rl(expr, &rl))
2107 		return false;
2108 	if (rl_type(rl) != &int_ctype)
2109 		return false;
2110 	if (rl_min(rl).value >= -4095 &&
2111 	    rl_max(rl).value < 0)
2112 		return true;
2113 	return false;
2114 }
2115 
2116 static void call_return_state_hooks(struct expression *expr)
2117 {
2118 	struct returned_state_callback *cb;
2119 	struct range_list *ret_rl;
2120 	const char *return_ranges;
2121 	int nr_states;
2122 	sval_t sval;
2123 
2124 	if (__path_is_null())
2125 		return;
2126 
2127 	expr = strip_expr(expr);
2128 	expr = strip_expr_statement(expr);
2129 
2130 	if (is_impossible_path())
2131 		goto vanilla;
2132 
2133 	if (expr && (expr->type == EXPR_COMPARE ||
2134 		     !get_implied_value(expr, &sval)) &&
2135 	    (is_condition(expr) || is_boolean(expr))) {
2136 		call_return_state_hooks_compare(expr);
2137 		return;
2138 	} else if (call_return_state_hooks_conditional(expr)) {
2139 		return;
2140 	} else if (is_kernel_error_path(expr)) {
2141 		goto vanilla;
2142 	} else if (call_return_state_hooks_split_possible(expr)) {
2143 		return;
2144 	} else if (split_positive_from_negative(expr)) {
2145 		return;
2146 	} else if (call_return_state_hooks_split_null_non_null_zero(expr)) {
2147 		return;
2148 	} else if (call_return_state_hooks_split_success_fail(expr)) {
2149 		return;
2150 	} else if (splitable_function_call(expr)) {
2151 		return;
2152 	} else if (split_by_bool_param(expr)) {
2153 	} else if (split_by_null_nonnull_param(expr)) {
2154 		return;
2155 	}
2156 
2157 vanilla:
2158 	return_ranges = get_return_ranges_str(expr, &ret_rl);
2159 	set_state(RETURN_ID, "return_ranges", NULL, alloc_estate_rl(ret_rl));
2160 
2161 	return_id++;
2162 	nr_states = get_db_state_count();
2163 	if (nr_states >= 10000) {
2164 		match_return_info(return_id, (char *)return_ranges, expr);
2165 		print_limited_param_set(return_id, (char *)return_ranges, expr);
2166 		mark_all_params_untracked(return_id, (char *)return_ranges, expr);
2167 		return;
2168 	}
2169 	FOR_EACH_PTR(returned_state_callbacks, cb) {
2170 		cb->callback(return_id, (char *)return_ranges, expr);
2171 	} END_FOR_EACH_PTR(cb);
2172 }
2173 
2174 static void print_returned_struct_members(int return_id, char *return_ranges, struct expression *expr)
2175 {
2176 	struct returned_member_callback *cb;
2177 	struct stree *stree;
2178 	struct sm_state *sm;
2179 	struct symbol *type;
2180 	char *name;
2181 	char member_name[256];
2182 	int len;
2183 
2184 	type = get_type(expr);
2185 	if (!type || type->type != SYM_PTR)
2186 		return;
2187 	name = expr_to_var(expr);
2188 	if (!name)
2189 		return;
2190 
2191 	member_name[sizeof(member_name) - 1] = '\0';
2192 	strcpy(member_name, "$");
2193 
2194 	len = strlen(name);
2195 	FOR_EACH_PTR(returned_member_callbacks, cb) {
2196 		stree = __get_cur_stree();
2197 		FOR_EACH_MY_SM(cb->owner, stree, sm) {
2198 			if (sm->name[0] == '*' && strcmp(sm->name + 1, name) == 0) {
2199 				strcpy(member_name, "*$");
2200 				cb->callback(return_id, return_ranges, expr, member_name, sm->state);
2201 				continue;
2202 			}
2203 			if (strncmp(sm->name, name, len) != 0)
2204 				continue;
2205 			if (strncmp(sm->name + len, "->", 2) != 0)
2206 				continue;
2207 			snprintf(member_name, sizeof(member_name), "$%s", sm->name + len);
2208 			cb->callback(return_id, return_ranges, expr, member_name, sm->state);
2209 		} END_FOR_EACH_SM(sm);
2210 	} END_FOR_EACH_PTR(cb);
2211 
2212 	free_string(name);
2213 }
2214 
2215 static void reset_memdb(struct symbol *sym)
2216 {
2217 	mem_sql(NULL, NULL, "delete from caller_info;");
2218 	mem_sql(NULL, NULL, "delete from return_states;");
2219 	mem_sql(NULL, NULL, "delete from call_implies;");
2220 	mem_sql(NULL, NULL, "delete from return_implies;");
2221 }
2222 
2223 static void match_end_func_info(struct symbol *sym)
2224 {
2225 	if (__path_is_null())
2226 		return;
2227 	call_return_state_hooks(NULL);
2228 }
2229 
2230 static void match_after_func(struct symbol *sym)
2231 {
2232 	if (!__inline_fn)
2233 		reset_memdb(sym);
2234 }
2235 
2236 static void init_memdb(void)
2237 {
2238 	char *err = NULL;
2239 	int rc;
2240 	const char *schema_files[] = {
2241 		"db/db.schema",
2242 		"db/caller_info.schema",
2243 		"db/common_caller_info.schema",
2244 		"db/return_states.schema",
2245 		"db/function_type_size.schema",
2246 		"db/type_size.schema",
2247 		"db/function_type_info.schema",
2248 		"db/type_info.schema",
2249 		"db/call_implies.schema",
2250 		"db/return_implies.schema",
2251 		"db/function_ptr.schema",
2252 		"db/local_values.schema",
2253 		"db/function_type_value.schema",
2254 		"db/type_value.schema",
2255 		"db/function_type.schema",
2256 		"db/data_info.schema",
2257 		"db/parameter_name.schema",
2258 		"db/constraints.schema",
2259 		"db/constraints_required.schema",
2260 		"db/fn_ptr_data_link.schema",
2261 		"db/fn_data_link.schema",
2262 		"db/mtag_about.schema",
2263 		"db/mtag_info.schema",
2264 		"db/mtag_map.schema",
2265 		"db/mtag_data.schema",
2266 		"db/mtag_alias.schema",
2267 	};
2268 	static char buf[4096];
2269 	int fd;
2270 	int ret;
2271 	int i;
2272 
2273 	rc = sqlite3_open(":memory:", &mem_db);
2274 	if (rc != SQLITE_OK) {
2275 		sm_ierror("starting In-Memory database.");
2276 		return;
2277 	}
2278 
2279 	for (i = 0; i < ARRAY_SIZE(schema_files); i++) {
2280 		fd = open_schema_file(schema_files[i]);
2281 		if (fd < 0)
2282 			continue;
2283 		ret = read(fd, buf, sizeof(buf));
2284 		if (ret < 0) {
2285 			sm_ierror("failed to read: %s", schema_files[i]);
2286 			continue;
2287 		}
2288 		close(fd);
2289 		if (ret == sizeof(buf)) {
2290 			sm_ierror("Schema file too large:  %s (limit %zd bytes)",
2291 			       schema_files[i], sizeof(buf));
2292 			continue;
2293 		}
2294 		buf[ret] = '\0';
2295 		rc = sqlite3_exec(mem_db, buf, NULL, NULL, &err);
2296 		if (rc != SQLITE_OK) {
2297 			sm_ierror("SQL error #2: %s", err);
2298 			sm_ierror("%s", buf);
2299 		}
2300 	}
2301 }
2302 
2303 static void init_cachedb(void)
2304 {
2305 	char *err = NULL;
2306 	int rc;
2307 	const char *schema_files[] = {
2308 		"db/call_implies.schema",
2309 		"db/return_implies.schema",
2310 		"db/type_info.schema",
2311 		"db/mtag_about.schema",
2312 		"db/mtag_data.schema",
2313 		"db/mtag_info.schema",
2314 		"db/sink_info.schema",
2315 	};
2316 	static char buf[4096];
2317 	int fd;
2318 	int ret;
2319 	int i;
2320 
2321 	rc = sqlite3_open(":memory:", &cache_db);
2322 	if (rc != SQLITE_OK) {
2323 		sm_ierror("starting In-Memory database.");
2324 		return;
2325 	}
2326 
2327 	for (i = 0; i < ARRAY_SIZE(schema_files); i++) {
2328 		fd = open_schema_file(schema_files[i]);
2329 		if (fd < 0)
2330 			continue;
2331 		ret = read(fd, buf, sizeof(buf));
2332 		if (ret < 0) {
2333 			sm_ierror("failed to read: %s", schema_files[i]);
2334 			continue;
2335 		}
2336 		close(fd);
2337 		if (ret == sizeof(buf)) {
2338 			sm_ierror("Schema file too large:  %s (limit %zd bytes)",
2339 			       schema_files[i], sizeof(buf));
2340 			continue;
2341 		}
2342 		buf[ret] = '\0';
2343 		rc = sqlite3_exec(cache_db, buf, NULL, NULL, &err);
2344 		if (rc != SQLITE_OK) {
2345 			sm_ierror("SQL error #2: %s", err);
2346 			sm_ierror("%s", buf);
2347 		}
2348 	}
2349 }
2350 
2351 static int save_cache_data(void *_table, int argc, char **argv, char **azColName)
2352 {
2353 	static char buf[4096];
2354 	char tmp[256];
2355 	char *p = buf;
2356 	char *table = _table;
2357 	int i;
2358 
2359 
2360 	p += snprintf(p, 4096 - (p - buf), "insert or ignore into %s values (", table);
2361 	for (i = 0; i < argc; i++) {
2362 		if (i)
2363 			p += snprintf(p, 4096 - (p - buf), ", ");
2364 		sqlite3_snprintf(sizeof(tmp), tmp, "%q", escape_newlines(argv[i]));
2365 		p += snprintf(p, 4096 - (p - buf), "'%s'", tmp);
2366 
2367 	}
2368 	p += snprintf(p, 4096 - (p - buf), ");");
2369 	if (p - buf > 4096)
2370 		return 0;
2371 
2372 	sm_msg("SQL: %s", buf);
2373 	return 0;
2374 }
2375 
2376 static void dump_cache(struct symbol_list *sym_list)
2377 {
2378 	const char *cache_tables[] = {
2379 		"type_info", "return_implies", "call_implies", "mtag_data",
2380 		"mtag_info", "mtag_about", "sink_info",
2381 	};
2382 	char buf[64];
2383 	int i;
2384 
2385 	if (!option_info)
2386 		return;
2387 
2388 	for (i = 0; i < ARRAY_SIZE(cache_tables); i++) {
2389 		snprintf(buf, sizeof(buf), "select * from %s;", cache_tables[i]);
2390 		cache_sql(&save_cache_data, (char *)cache_tables[i], buf);
2391 	}
2392 }
2393 
2394 void open_smatch_db(char *db_file)
2395 {
2396 	int rc;
2397 
2398 	if (option_no_db)
2399 		return;
2400 
2401 	use_states = malloc(num_checks + 1);
2402 	memset(use_states, 0xff, num_checks + 1);
2403 
2404 	init_memdb();
2405 	init_cachedb();
2406 
2407 	rc = sqlite3_open_v2(db_file, &smatch_db, SQLITE_OPEN_READONLY, NULL);
2408 	if (rc != SQLITE_OK) {
2409 		option_no_db = 1;
2410 		return;
2411 	}
2412 	run_sql(NULL, NULL,
2413 		"PRAGMA cache_size = %d;", SQLITE_CACHE_PAGES);
2414 	return;
2415 }
2416 
2417 static void register_common_funcs(void)
2418 {
2419 	struct token *token;
2420 	char *func;
2421 	char filename[256];
2422 
2423 	if (option_project == PROJ_NONE)
2424 		strcpy(filename, "common_functions");
2425 	else
2426 		snprintf(filename, 256, "%s.common_functions", option_project_str);
2427 
2428 	token = get_tokens_file(filename);
2429 	if (!token)
2430 		return;
2431 	if (token_type(token) != TOKEN_STREAMBEGIN)
2432 		return;
2433 	token = token->next;
2434 	while (token_type(token) != TOKEN_STREAMEND) {
2435 		if (token_type(token) != TOKEN_IDENT)
2436 			return;
2437 		func = alloc_string(show_ident(token->ident));
2438 		add_ptr_list(&common_funcs, func);
2439 		token = token->next;
2440 	}
2441 	clear_token_alloc();
2442 }
2443 
2444 static char *get_next_string(char **str)
2445 {
2446 	static char string[256];
2447 	char *start;
2448 	char *p = *str;
2449 	int len, i, j;
2450 
2451 	if (*p == '\0')
2452 		return NULL;
2453 	start = p;
2454 
2455 	while (*p != '\0' && *p != '\n') {
2456 		if (*p == '\\' && *(p + 1) == ' ') {
2457 			p += 2;
2458 			continue;
2459 		}
2460 		if (*p == ' ')
2461 			break;
2462 		p++;
2463 	}
2464 
2465 	len = p - start;
2466 	if (len >= sizeof(string)) {
2467 		memcpy(string, start, sizeof(string));
2468 		string[sizeof(string) - 1] = '\0';
2469 		sm_ierror("return_fix: '%s' too long", string);
2470 		**str = '\0';
2471 		return NULL;
2472 	}
2473 	memcpy(string, start, len);
2474 	string[len] = '\0';
2475 	for (i = 0; i < sizeof(string) - 1; i++) {
2476 		if (string[i] == '\\' && string[i + 1] == ' ') {
2477 			for (j = i; string[j] != '\0'; j++)
2478 				string[j] = string[j + 1];
2479 		}
2480 	}
2481 	if (*p != '\0')
2482 		p++;
2483 	*str = p;
2484 	return string;
2485 }
2486 
2487 static void register_return_replacements(void)
2488 {
2489 	char *func, *orig, *new;
2490 	char filename[256];
2491 	char buf[4096];
2492 	int fd, ret, i;
2493 	char *p;
2494 
2495 	snprintf(filename, 256, "db/%s.return_fixes", option_project_str);
2496 	fd = open_schema_file(filename);
2497 	if (fd < 0)
2498 		return;
2499 	ret = read(fd, buf, sizeof(buf));
2500 	close(fd);
2501 	if (ret < 0)
2502 		return;
2503 	if (ret == sizeof(buf)) {
2504 		sm_ierror("file too large:  %s (limit %zd bytes)",
2505 		       filename, sizeof(buf));
2506 		return;
2507 	}
2508 	buf[ret] = '\0';
2509 
2510 	p = buf;
2511 	while (*p) {
2512 		get_next_string(&p);
2513 		replace_count++;
2514 	}
2515 	if (replace_count == 0 || replace_count % 3 != 0) {
2516 		replace_count = 0;
2517 		return;
2518 	}
2519 	replace_table = malloc(replace_count * sizeof(char *));
2520 
2521 	p = buf;
2522 	i = 0;
2523 	while (*p) {
2524 		func = alloc_string(get_next_string(&p));
2525 		orig = alloc_string(get_next_string(&p));
2526 		new  = alloc_string(get_next_string(&p));
2527 
2528 		replace_table[i++] = func;
2529 		replace_table[i++] = orig;
2530 		replace_table[i++] = new;
2531 	}
2532 }
2533 
2534 void register_definition_db_callbacks(int id)
2535 {
2536 	add_hook(&match_call_info, FUNCTION_CALL_HOOK);
2537 	add_hook(&match_call_info_new, FUNCTION_CALL_HOOK);
2538 	add_split_return_callback(match_return_info);
2539 	add_split_return_callback(print_returned_struct_members);
2540 	add_hook(&call_return_state_hooks, RETURN_HOOK);
2541 	add_hook(&match_end_func_info, END_FUNC_HOOK);
2542 	add_hook(&match_after_func, AFTER_FUNC_HOOK);
2543 
2544 	add_hook(&match_data_from_db, FUNC_DEF_HOOK);
2545 	add_hook(&match_call_implies, FUNC_DEF_HOOK);
2546 	add_hook(&match_return_implies, CALL_HOOK_AFTER_INLINE);
2547 
2548 	register_common_funcs();
2549 	register_return_replacements();
2550 
2551 	add_hook(&dump_cache, END_FILE_HOOK);
2552 }
2553 
2554 void register_db_call_marker(int id)
2555 {
2556 	add_hook(&match_call_marker, FUNCTION_CALL_HOOK);
2557 }
2558 
2559 char *return_state_to_var_sym(struct expression *expr, int param, const char *key, struct symbol **sym)
2560 {
2561 	struct expression *arg;
2562 	char *name = NULL;
2563 	char member_name[256];
2564 
2565 	*sym = NULL;
2566 
2567 	if (param == -1) {
2568 		const char *star = "";
2569 
2570 		if (expr->type != EXPR_ASSIGNMENT)
2571 			return NULL;
2572 		if (get_type(expr->left) == &int_ctype && strcmp(key, "$") != 0)
2573 			return NULL;
2574 		name = expr_to_var_sym(expr->left, sym);
2575 		if (!name)
2576 			return NULL;
2577 		if (key[0] == '*') {
2578 			star = "*";
2579 			key++;
2580 		}
2581 		if (strncmp(key, "$", 1) != 0)
2582 			return name;
2583 		snprintf(member_name, sizeof(member_name), "%s%s%s", star, name, key + 1);
2584 		free_string(name);
2585 		return alloc_string(member_name);
2586 	}
2587 
2588 	while (expr->type == EXPR_ASSIGNMENT)
2589 		expr = strip_expr(expr->right);
2590 	if (expr->type != EXPR_CALL)
2591 		return NULL;
2592 
2593 	arg = get_argument_from_call_expr(expr->args, param);
2594 	if (!arg)
2595 		return NULL;
2596 
2597 	return get_variable_from_key(arg, key, sym);
2598 }
2599 
2600 char *get_variable_from_key(struct expression *arg, const char *key, struct symbol **sym)
2601 {
2602 	struct symbol *type;
2603 	char buf[256];
2604 	char *tmp;
2605 	int star_cnt = 0;
2606 	bool add_dot = false;
2607 
2608 	if (!arg)
2609 		return NULL;
2610 
2611 	arg = strip_expr(arg);
2612 
2613 	if (strcmp(key, "$") == 0)
2614 		return expr_to_var_sym(arg, sym);
2615 
2616 	if (strcmp(key, "*$") == 0) {
2617 		if (arg->type == EXPR_PREOP && arg->op == '&') {
2618 			arg = strip_expr(arg->unop);
2619 			return expr_to_var_sym(arg, sym);
2620 		} else {
2621 			tmp = expr_to_var_sym(arg, sym);
2622 			if (!tmp)
2623 				return NULL;
2624 			snprintf(buf, sizeof(buf), "*%s", tmp);
2625 			free_string(tmp);
2626 			return alloc_string(buf);
2627 		}
2628 	}
2629 
2630 	if (strncmp(key, "(*$)", 4) == 0) {
2631 		char buf[64];
2632 
2633 		if (arg->type == EXPR_PREOP && arg->op == '&') {
2634 			arg = strip_expr(arg->unop);
2635 			snprintf(buf, sizeof(buf), "$%s", key + 4);
2636 			return get_variable_from_key(arg, buf, sym);
2637 		} else {
2638 			tmp = expr_to_var_sym(arg, sym);
2639 			if (!tmp)
2640 				return NULL;
2641 			snprintf(buf, sizeof(buf), "(*%s)%s", tmp, key + 4);
2642 			free_string(tmp);
2643 			return alloc_string(buf);
2644 		}
2645 	}
2646 
2647 	while (key[0] == '*') {
2648 		star_cnt++;
2649 		key++;
2650 	}
2651 
2652 	/*
2653 	 * FIXME:  This is a hack.
2654 	 * We should be able to parse expressions like (*$)->foo and *$->foo.
2655 	 */
2656 	type = get_type(arg);
2657 	if (is_struct_ptr(type))
2658 		add_dot = true;
2659 
2660 	if (arg->type == EXPR_PREOP && arg->op == '&' && star_cnt && !add_dot) {
2661 		arg = strip_expr(arg->unop);
2662 		star_cnt--;
2663 	}
2664 
2665 	if (arg->type == EXPR_PREOP && arg->op == '&') {
2666 		arg = strip_expr(arg->unop);
2667 		tmp = expr_to_var_sym(arg, sym);
2668 		if (!tmp)
2669 			return NULL;
2670 		snprintf(buf, sizeof(buf), "%.*s%s.%s",
2671 			 star_cnt, "**********", tmp, key + 3);
2672 		return alloc_string(buf);
2673 	}
2674 
2675 	tmp = expr_to_var_sym(arg, sym);
2676 	if (!tmp)
2677 		return NULL;
2678 	snprintf(buf, sizeof(buf), "%.*s%s%s", star_cnt, "**********", tmp, key + 1);
2679 	free_string(tmp);
2680 	return alloc_string(buf);
2681 }
2682 
2683 char *get_chunk_from_key(struct expression *arg, char *key, struct symbol **sym, struct var_sym_list **vsl)
2684 {
2685 	*vsl = NULL;
2686 
2687 	if (strcmp("$", key) == 0)
2688 		return expr_to_chunk_sym_vsl(arg, sym, vsl);
2689 	return get_variable_from_key(arg, key, sym);
2690 }
2691 
2692 const char *state_name_to_param_name(const char *state_name, const char *param_name)
2693 {
2694 	int star_cnt = 0;
2695 	int name_len;
2696 	char buf[256];
2697 
2698 	name_len = strlen(param_name);
2699 
2700 	while (state_name[0] == '*') {
2701 		star_cnt++;
2702 		state_name++;
2703 	}
2704 
2705 	/* ten out of ten stars! */
2706 	if (star_cnt > 10)
2707 		return NULL;
2708 
2709 	if (strncmp(state_name, "(*", 2) == 0 &&
2710 	    strncmp(state_name + 2, param_name, name_len) == 0 &&
2711 	    state_name[name_len + 2] == ')') {
2712 		snprintf(buf, sizeof(buf), "%.*s(*$)%s", star_cnt, "**********",
2713 			 state_name + name_len + 3);
2714 		return alloc_sname(buf);
2715 	}
2716 
2717 	if (strcmp(state_name, param_name) == 0) {
2718 		snprintf(buf, sizeof(buf), "%.*s$", star_cnt, "**********");
2719 		return alloc_sname(buf);
2720 	}
2721 
2722 	/* check for '-' from "->" */
2723 	if (strncmp(state_name, param_name, name_len) == 0 &&
2724 	    state_name[name_len] == '-') {
2725 		snprintf(buf, sizeof(buf), "%.*s$%s", star_cnt, "**********", state_name + name_len);
2726 		return alloc_sname(buf);
2727 	}
2728 	return NULL;
2729 }
2730 
2731 const char *get_param_name_var_sym(const char *name, struct symbol *sym)
2732 {
2733 	if (!sym || !sym->ident)
2734 		return NULL;
2735 
2736 	return state_name_to_param_name(name, sym->ident->name);
2737 }
2738 
2739 const char *get_mtag_name_var_sym(const char *state_name, struct symbol *sym)
2740 {
2741 	struct symbol *type;
2742 	const char *sym_name;
2743 	int name_len;
2744 	static char buf[256];
2745 
2746 	/*
2747 	 * mtag_name is different from param_name because mtags can be a struct
2748 	 * instead of a struct pointer.  But we want to treat it like a pointer
2749 	 * because really an mtag is a pointer.  Or in other words, if you pass
2750 	 * a struct foo then you want to talk about foo.bar but with an mtag
2751 	 * you want to refer to it as foo->bar.
2752 	 *
2753 	 */
2754 
2755 	if (!sym || !sym->ident)
2756 		return NULL;
2757 
2758 	type = get_real_base_type(sym);
2759 	if (type && type->type == SYM_BASETYPE)
2760 		return "*$";
2761 
2762 	sym_name = sym->ident->name;
2763 	name_len = strlen(sym_name);
2764 
2765 	if (state_name[name_len] == '.' && /* check for '-' from "->" */
2766 	    strncmp(state_name, sym_name, name_len) == 0) {
2767 		snprintf(buf, sizeof(buf), "$->%s", state_name + name_len + 1);
2768 		return buf;
2769 	}
2770 
2771 	return state_name_to_param_name(state_name, sym_name);
2772 }
2773 
2774 const char *get_mtag_name_expr(struct expression *expr)
2775 {
2776 	char *name;
2777 	struct symbol *sym;
2778 	const char *ret = NULL;
2779 
2780 	name = expr_to_var_sym(expr, &sym);
2781 	if (!name || !sym)
2782 		goto free;
2783 
2784 	ret = get_mtag_name_var_sym(name, sym);
2785 free:
2786 	free_string(name);
2787 	return ret;
2788 }
2789 
2790 const char *get_param_name(struct sm_state *sm)
2791 {
2792 	return get_param_name_var_sym(sm->name, sm->sym);
2793 }
2794 
2795 char *get_data_info_name(struct expression *expr)
2796 {
2797 	struct symbol *sym;
2798 	char *name;
2799 	char buf[256];
2800 	char *ret = NULL;
2801 
2802 	expr = strip_expr(expr);
2803 	name = get_member_name(expr);
2804 	if (name)
2805 		return name;
2806 	name = expr_to_var_sym(expr, &sym);
2807 	if (!name || !sym)
2808 		goto free;
2809 	if (!(sym->ctype.modifiers & MOD_TOPLEVEL))
2810 		goto free;
2811 	if (sym->ctype.modifiers & MOD_STATIC)
2812 		snprintf(buf, sizeof(buf), "static %s", name);
2813 	else
2814 		snprintf(buf, sizeof(buf), "global %s", name);
2815 	ret = alloc_sname(buf);
2816 free:
2817 	free_string(name);
2818 	return ret;
2819 }
2820