smatch_var_sym.c

   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 "smatch.h"
  19
  20 ALLOCATOR(var_sym, "var_sym structs");
  21
  22 struct var_sym *alloc_var_sym(const char *var, struct symbol *sym)
  23 {
  24         struct var_sym *tmp;
  25
  26         tmp = __alloc_var_sym(0);
  27         tmp->var = alloc_string(var);
  28         tmp->sym = sym;
  29         return tmp;
  30 }
  31
  32 struct var_sym_list *expr_to_vsl(struct expression *expr)
  33 {
  34         struct expression *unop;
  35         struct var_sym_list *ret = NULL;
  36         char *var;
  37         struct symbol *sym;
  38
  39         expr = strip_expr(expr);
  40         if (!expr)
  41                 return NULL;
  42
  43         if ((expr->type == EXPR_PREOP && expr->op == '*') ||
  44             expr->type == EXPR_DEREF) {
  45                 unop = strip_expr(expr->unop);
  46
  47                 if (unop->type == EXPR_SYMBOL)
  48                         goto one_var;
  49                 return expr_to_vsl(unop);
  50         }
  51
  52         if (expr->type == EXPR_BINOP ||
  53             expr->type == EXPR_LOGICAL ||
  54             expr->type == EXPR_COMPARE) {
  55                 struct var_sym_list *left, *right;
  56
  57                 left = expr_to_vsl(expr->left);
  58                 right = expr_to_vsl(expr->right);
  59                 ret = combine_var_sym_lists(left, right);
  60                 free_var_syms_and_list(&left);
  61                 free_var_syms_and_list(&right);
  62                 return ret;
  63         }
  64
  65 one_var:
  66         var = expr_to_var_sym(expr, &sym);
  67         if (!var || !sym) {
  68                 free_string(var);
  69                 return NULL;
  70         }
  71         add_var_sym(&ret, var, sym);
  72         return ret;
  73 }
  74
  75 int cmp_var_sym(const struct var_sym *a, const struct var_sym *b)
  76 {
  77         int ret;
  78
  79         if (a == b)
  80                 return 0;
  81         if (!b)
  82                 return -1;
  83         if (!a)
  84                 return 1;
  85
  86         ret = strcmp(a->var, b->var);
  87         if (ret < 0)
  88                 return -1;
  89         if (ret > 0)
  90                 return 1;
  91
  92         if (!b->sym && a->sym)
  93                 return -1;
  94         if (!a->sym && b->sym)
  95                 return 1;
  96         if (a->sym < b->sym)
  97                 return -1;
  98         if (a->sym > b->sym)
  99                 return 1;
 100
 101         return 0;
 102 }
 103
 104 void add_var_sym(struct var_sym_list **list, const char *var, struct symbol *sym)
 105 {
 106         struct var_sym *tmp, *new;
 107
 108         if (in_var_sym_list(*list, var, sym))
 109                 return;
 110         new = alloc_var_sym(var, sym);
 111
 112         FOR_EACH_PTR(*list, tmp) {
 113                 if (cmp_var_sym(tmp, new) < 0)
 114                         continue;
 115                 else if (cmp_var_sym(tmp, new) == 0) {
 116                         return;
 117                 } else {
 118                         INSERT_CURRENT(new, tmp);
 119                         return;
 120                 }
 121         } END_FOR_EACH_PTR(tmp);
 122         add_ptr_list(list, new);
 123 }
 124
 125 void add_var_sym_expr(struct var_sym_list **list, struct expression *expr)
 126 {
 127         char *var;
 128         struct symbol *sym;
 129
 130         var = expr_to_var_sym(expr, &sym);
 131         if (!var || !sym)
 132                 goto free;
 133         add_var_sym(list, var, sym);
 134 free:
 135         free_string(var);
 136 }
 137
 138 static void free_var_sym(struct var_sym *vs)
 139 {
 140         free_string(vs->var);
 141         __free_var_sym(vs);
 142 }
 143
 144 void del_var_sym(struct var_sym_list **list, const char *var, struct symbol *sym)
 145 {
 146         struct var_sym *tmp;
 147
 148         FOR_EACH_PTR(*list, tmp) {
 149                 if (tmp->sym == sym && strcmp(tmp->var, var) == 0) {
 150                         DELETE_CURRENT_PTR(tmp);
 151                         free_var_sym(tmp);
 152                         return;
 153                 }
 154         } END_FOR_EACH_PTR(tmp);
 155 }
 156
 157 int in_var_sym_list(struct var_sym_list *list, const char *var, struct symbol *sym)
 158 {
 159         struct var_sym *tmp;
 160
 161         FOR_EACH_PTR(list, tmp) {
 162                 if (tmp->sym == sym && strcmp(tmp->var, var) == 0)
 163                         return 1;
 164         } END_FOR_EACH_PTR(tmp);
 165         return 0;
 166 }
 167
 168 struct var_sym_list *clone_var_sym_list(struct var_sym_list *from_vsl)
 169 {
 170         struct var_sym *tmp, *clone_vs;
 171         struct var_sym_list *to_vsl = NULL;
 172
 173         FOR_EACH_PTR(from_vsl, tmp) {
 174                 clone_vs = alloc_var_sym(tmp->var, tmp->sym);
 175                 add_ptr_list(&to_vsl, clone_vs);
 176         } END_FOR_EACH_PTR(tmp);
 177         return to_vsl;
 178 }
 179
 180 void merge_var_sym_list(struct var_sym_list **dest, struct var_sym_list *src)
 181 {
 182         struct var_sym *tmp;
 183
 184         FOR_EACH_PTR(src, tmp) {
 185                 add_var_sym(dest, tmp->var, tmp->sym);
 186         } END_FOR_EACH_PTR(tmp);
 187 }
 188
 189 struct var_sym_list *combine_var_sym_lists(struct var_sym_list *one, struct var_sym_list *two)
 190 {
 191         struct var_sym_list *to_vsl;
 192
 193         to_vsl = clone_var_sym_list(one);
 194         merge_var_sym_list(&to_vsl, two);
 195         return to_vsl;
 196 }
 197
 198 int var_sym_lists_equiv(struct var_sym_list *one, struct var_sym_list *two)
 199 {
 200         struct var_sym *one_tmp, *two_tmp;
 201
 202         if (one == two)
 203                 return 1;
 204
 205         if (ptr_list_size((struct ptr_list *)one) != ptr_list_size((struct ptr_list *)two))
 206                 return 0;
 207
 208         PREPARE_PTR_LIST(one, one_tmp);
 209         PREPARE_PTR_LIST(two, two_tmp);
 210         for (;;) {
 211                 if (!one_tmp && !two_tmp)
 212                         return 1;
 213                 if (one_tmp->sym != two_tmp->sym)
 214                         return 0;
 215                 if (strcmp(one_tmp->var, two_tmp->var) != 0)
 216                         return 0;
 217                 NEXT_PTR_LIST(one_tmp);
 218                 NEXT_PTR_LIST(two_tmp);
 219         }
 220         FINISH_PTR_LIST(two_tmp);
 221         FINISH_PTR_LIST(one_tmp);
 222
 223         return 1;
 224 }
 225
 226 void free_var_sym_list(struct var_sym_list **list)
 227 {
 228         __free_ptr_list((struct ptr_list **)list);
 229 }
 230
 231 void free_var_syms_and_list(struct var_sym_list **list)
 232 {
 233         struct var_sym *tmp;
 234
 235         FOR_EACH_PTR(*list, tmp) {
 236                 free_var_sym(tmp);
 237         } END_FOR_EACH_PTR(tmp);
 238         free_var_sym_list(list);
 239 }
 240