Sweep-fix comparing pointers with 0 (and assigning 0 to pointers).
[dragonfly.git] / usr.bin / window / parser5.c
1 /*      @(#)parser5.c   8.1 (Berkeley) 6/6/93   */
2 /*      $NetBSD: parser5.c,v 1.7 2009/04/14 08:50:06 lukem Exp $        */
3
4 /*
5  * Copyright (c) 1983, 1993
6  *      The Regents of the University of California.  All rights reserved.
7  *
8  * This code is derived from software contributed to Berkeley by
9  * Edward Wang at The University of California, Berkeley.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions and the following disclaimer.
16  * 2. Redistributions in binary form must reproduce the above copyright
17  *    notice, this list of conditions and the following disclaimer in the
18  *    documentation and/or other materials provided with the distribution.
19  * 3. Neither the name of the University nor the names of its contributors
20  *    may be used to endorse or promote products derived from this software
21  *    without specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33  * SUCH DAMAGE.
34  */
35
36 #include "defs.h"
37 #include "parser.h"
38 #include "var.h"
39
40 /*
41  * unary $ $? + - ! ~
42  */
43 int
44 p_expr11(struct value *v, char flag)
45 {
46         int op;
47         const char *opname;
48
49         switch (token) {
50         case T_DOLLAR:
51                 opname = "$";
52                 break;
53         case T_DQ:
54                 opname = "$?";
55                 break;
56         case T_PLUS:
57                 opname = "unary +";
58                 break;
59         case T_MINUS:
60                 opname = "unary -";
61                 break;
62         case T_NOT:
63                 opname = "!";
64                 break;
65         case T_COMP:
66                 opname = "~";
67                 break;
68         default:
69                 return p_expr12(v, flag);
70         }
71         op = token;
72         (void) s_gettok();
73         if (p_expr11(v, flag) < 0)
74                 return -1;
75         switch (v->v_type) {
76         case V_NUM:
77                 break;
78         case V_STR:
79                 switch (op) {
80                 case T_MINUS:
81                 case T_NOT:
82                 case T_COMP:
83                         p_error("%s: Numeric operand required.", opname);
84                         str_free(v->v_str);
85                         v->v_type = V_ERR;
86                         return 0;
87                 }
88                 break;
89         case V_ERR:
90                 return 0;
91         }
92         switch (op) {
93         case T_DOLLAR:
94         case T_DQ:
95                 if (v->v_type == V_NUM) {
96                         int tmp = cx.x_type == X_BUF && cx.x_arg != 0 &&
97                                 v->v_num > 0 && v->v_num <= cx.x_narg;
98                         if (op == T_DQ)
99                                 v->v_num = tmp;
100                         else if (tmp)
101                                 *v = cx.x_arg[v->v_num - 1];
102                         else {
103                                 p_error("%d: No such argument.", v->v_num);
104                                 v->v_type = V_ERR;
105                         }
106                 } else {
107                         char *name = v->v_str;
108                         struct var *r = var_lookup(name);
109                         if (op == T_DQ) {
110                                 v->v_type = V_NUM;
111                                 v->v_num = r != NULL;
112                         } else if (r != NULL)
113                                 *v = r->r_val;
114                         else {
115                                 p_error("%s: Undefined variable.", name);
116                                 v->v_type = V_ERR;
117                         }
118                         str_free(name);
119                 }
120                 if (v->v_type == V_STR && (v->v_str = str_cpy(v->v_str)) == 0) {
121                         p_memerror();
122                         return -1;
123                 }
124                 break;
125         case T_MINUS:
126                 v->v_num = - v->v_num;
127                 break;
128         case T_NOT:
129                 v->v_num = ! v->v_num;
130                 break;
131         case T_COMP:
132                 v->v_num = ~ v->v_num;
133                 break;
134         }
135         return 0;
136 }
137
138 /*
139  * string, number, ( expr )
140  * Plus function calls.
141  *
142  * Always return v_type == V_ERR when flag == 0.
143  */
144 int
145 p_expr12(struct value *v, char flag)
146 {
147         v->v_type = V_ERR;
148         switch (token) {
149         case T_NUM:
150                 if (flag) {
151                         v->v_type = V_NUM;
152                         v->v_num = token_num;
153                 }
154                 (void) s_gettok();
155                 break;
156         case T_STR:
157                 if (flag) {
158                         v->v_type = V_STR;
159                         v->v_str = token_str;
160                 } else
161                         str_free(token_str);
162                 (void) s_gettok();
163                 break;
164         case T_LP:
165                 (void) s_gettok();
166                 if (p_expr(v, flag) < 0) {
167                         p_synerror();
168                         return -1;
169                 }
170                 if (token != T_RP) {
171                         p_synerror();
172                         val_free(*v);
173                         return -1;
174                 }
175                 (void) s_gettok();
176                 break;
177         default:
178                 return -1;
179         }
180         while (token == T_LP) {
181                 char *cmd;
182
183                 if (p_convstr(v) < 0)
184                         return -1;
185                 cmd = v->v_type == V_STR ? v->v_str : 0;
186                 if (p_function(cmd, v, flag) < 0) {
187                         if (cmd)
188                                 str_free(cmd);
189                         return -1;
190                 }
191                 if (cmd)
192                         str_free(cmd);
193         }
194         return 0;
195 }