1/*
2 * Copyright (C) 2009 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/*
19 * In wine you aren't allowed to compare file handles with 0,
20 * only with INVALID_HANDLE_VALUE.
21 *
22 */
23
24#include "smatch.h"
25
26static int my_id;
27
28STATE(filehandle);
29STATE(oktocheck);
30
31/* originally:
32 *  "(?:CreateFile|CreateMailslot|CreateNamedPipe|FindFirstFile(?:Ex)?|OpenConsole|SetupOpenInfFile|socket)[AW]?"
33 *
34 */
35static const char *filehandle_funcs[] = {
36	"CreateFile",
37	"CreateMailslot",
38	"CreateNamedPipe",
39	"FindFirstFile",
40	"FindFirstFileEx",
41	"OpenConsole",
42	"SetupOpenInfFile",
43	"socket",
44	NULL,
45};
46
47static void ok_to_use(struct sm_state *sm, struct expression *mod_expr)
48{
49	if (sm->state != &oktocheck)
50		set_state(my_id, sm->name, sm->sym, &oktocheck);
51}
52
53static void match_returns_handle(const char *fn, struct expression *expr,
54			     void *info)
55{
56	char *left_name = NULL;
57	struct symbol *left_sym;
58
59	left_name = expr_to_var_sym(expr->left, &left_sym);
60	if (!left_name || !left_sym)
61		goto free;
62	set_state_expr(my_id, expr->left, &filehandle);
63free:
64	free_string(left_name);
65}
66
67static void match_condition(struct expression *expr)
68{
69	if (expr->type == EXPR_ASSIGNMENT)
70		match_condition(expr->left);
71
72	if (get_state_expr(my_id, expr) == &filehandle) {
73		char *name;
74
75		name = expr_to_var(expr);
76		sm_error("comparing a filehandle against zero '%s'", name);
77		set_state_expr(my_id, expr, &oktocheck);
78		free_string(name);
79	}
80}
81
82void check_wine_filehandles(int id)
83{
84	int i;
85
86	if (option_project != PROJ_WINE)
87		return;
88
89	my_id = id;
90	for (i = 0; filehandle_funcs[i]; i++) {
91		add_function_assign_hook(filehandle_funcs[i],
92					 &match_returns_handle, NULL);
93	}
94	add_hook(&match_condition, CONDITION_HOOK);
95	add_modification_hook(my_id, ok_to_use);
96}
97