1 /*
2 * Copyright (C) 2013 Oracle.
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 "scope.h"
19 #include "smatch.h"
20 #include "smatch_slist.h"
21 #include "smatch_extra.h"
22
23 static int my_id;
24
25 /*
26 * I'm going to store the states of local data at the end of each function.
27 * Then at the end of the file, I'll combine the possible range lists for
28 * each state and store the value in the on-disk database.
29 *
30 * One issue is that when I read the data back from the in-memory database at
31 * the end of the file, then I don't have access to type information. I'll just
32 * cast everything to "long long" for now, I guess. We'll see how that works.
33 */
34
35 static char *db_vals;
36 static int get_vals(void *unused, int argc, char **argv, char **azColName)
37 {
38 db_vals = alloc_string(argv[0]);
39 return 0;
40 }
41
42 static int is_array_symbol(struct expression *expr)
43 {
44 struct symbol *type;
45
46 if (!expr || expr->type != EXPR_SYMBOL)
47 return 0;
48 type = get_type(expr);
49 if (!type)
50 return 0;
51 if (type->type == SYM_ARRAY)
52 return 1;
53 return 0;
54 }
55
56 int get_local_rl(struct expression *expr, struct range_list **rl)
57 {
58 char *name;
59 struct range_list *tmp;
60
61 if (!is_static(expr))
62 return 0;
63 if (is_array_symbol(expr))
64 return 0;
65 name = expr_to_var(expr);
66 if (!name)
67 return 0;
68
69 db_vals = NULL;
70 run_sql(get_vals, NULL,
71 "select value from local_values where file = '%s' and variable = '%s';",
72 get_filename(), name);
73 free_string(name);
74 if (!db_vals)
75 return 0;
76 str_to_rl(&llong_ctype, db_vals, &tmp);
77 *rl = cast_rl(get_type(expr), tmp);
78 free_string(db_vals);
79
80 return 1;
81 }
82
83 int get_local_max_helper(struct expression *expr, sval_t *sval)
84 {
85 struct range_list *rl;
86
87 if (!get_local_rl(expr, &rl))
88 return 0;
89 *sval = rl_max(rl);
90 return 1;
91 }
92
93 int get_local_min_helper(struct expression *expr, sval_t *sval)
94 {
95 struct range_list *rl;
96
97 if (!get_local_rl(expr, &rl))
98 return 0;
99 *sval = rl_min(rl);
100 return 1;
101 }
102
103 static struct smatch_state *unmatched_state(struct sm_state *sm)
104 {
105 return alloc_estate_empty();
106 }
107
108 static void extra_mod_hook(const char *name, struct symbol *sym, struct expression *expr, struct smatch_state *state)
109 {
110 struct smatch_state *old;
111 struct smatch_state *new;
112
113 if (!sym || !(sym->ctype.modifiers & MOD_STATIC))
114 return;
115 old = get_state(my_id, name, sym);
116 if (old)
117 new = merge_estates(old, state);
118 else
119 new = state;
120 set_state(my_id, name, sym, new);
121 }
122
123 static void process_states(void)
124 {
125 struct sm_state *sm;
126 struct smatch_state *extra;
127 struct range_list *rl;
128
129 FOR_EACH_SM(__get_cur_stree(), sm) {
130 if (sm->owner != my_id)
131 continue;
132 extra = get_state(SMATCH_EXTRA, sm->name, sm->sym);
133 if (extra && estate_rl(extra))
134 rl = rl_intersection(estate_rl(sm->state), estate_rl(extra));
135 else
136 rl = estate_rl(sm->state);
137 rl = cast_rl(&llong_ctype, rl);
138 mem_sql(NULL, NULL,
139 "insert into local_values values ('%s', '%s', '%s', %lu);",
140 get_filename(), sm->name, show_rl(rl),
141 (unsigned long)sm->sym);
142 } END_FOR_EACH_SM(sm);
143 }
144
145 static int get_initial_value_sym(struct symbol *sym, char *name, sval_t *sval)
146 {
147 struct expression *expr_symbol, *deref, *tmp;
148 char *member_name;
149
150 if (!sym)
151 return 0;
152
153 if (!sym->initializer) {
154 *sval = sval_type_val(&llong_ctype, 0);
155 return 1;
156 }
157 if (sym->initializer->type != EXPR_INITIALIZER)
158 return get_value(sym->initializer, sval);
159
160 expr_symbol = symbol_expression(sym);
161 FOR_EACH_PTR(sym->initializer->expr_list, tmp) {
162 if (tmp->type != EXPR_IDENTIFIER) /* how to handle arrays?? */
163 continue;
164 deref = member_expression(expr_symbol, '.', tmp->expr_ident);
165 member_name = expr_to_var(deref);
166 if (!member_name)
167 continue;
168 if (strcmp(name, member_name) == 0) {
169 free_string(member_name);
170 return get_value(tmp->ident_expression, sval);
171 }
172 free_string(member_name);
173 } END_FOR_EACH_PTR(tmp);
174
175 return 0;
176 }
177
178 static char *cur_name;
179 static struct symbol *cur_symbol;
180 static struct range_list *cur_rl;
181 static void add_current_local(void)
182 {
183 sval_t initial;
184
185 if (!get_initial_value_sym(cur_symbol, cur_name, &initial)) {
186 free_string(cur_name);
187 cur_name = NULL;
188 cur_rl = NULL;
189 return;
190 }
191 add_range(&cur_rl, initial, initial);
192 if (!is_whole_rl(cur_rl))
193 sql_insert_local_values(cur_name, show_rl(cur_rl));
194 free_string(cur_name);
195 cur_name = NULL;
196 cur_rl = NULL;
197 }
198
199 static int save_final_values(void *unused, int argc, char **argv, char **azColName)
200 {
201 char *name = argv[0];
202 char *sym_str = argv[1];
203 char *value = argv[2];
204 struct range_list *rl;
205
206 if (!cur_name) {
207 cur_name = alloc_string(name);
208 cur_symbol = (struct symbol *)strtoul(sym_str, NULL, 10);
209 } else if (strcmp(cur_name, name) != 0) {
210 add_current_local();
211 cur_name = alloc_string(name);
212 cur_symbol = (struct symbol *)strtoul(sym_str, NULL, 10);
213 cur_rl = NULL;
214 }
215
216 str_to_rl(&llong_ctype, value, &rl);
217 cur_rl = rl_union(cur_rl, rl);
218
219 return 0;
220 }
221
222 static void match_end_file(struct symbol_list *sym_list)
223 {
224 mem_sql(save_final_values, NULL,
225 "select distinct variable, symbol, value from local_values order by variable;");
226 if (cur_name)
227 add_current_local();
228 }
229
230 void register_local_values(int id)
231 {
232 my_id = id;
233
234 if (!option_info)
235 return;
236
237 set_dynamic_states(my_id);
238 add_extra_mod_hook(&extra_mod_hook);
239 add_unmatched_state_hook(my_id, &unmatched_state);
240 add_merge_hook(my_id, &merge_estates);
241 all_return_states_hook(&process_states);
242 add_hook(match_end_file, END_FILE_HOOK);
243 mem_sql(NULL, NULL, "alter table local_values add column symbol integer;");
244 }