projects / unix-history / blame
| Commit | Line | Data |
|---|---|---|
| 60de5df9 | 1 | /* |
| 46e9ea25 KB |
2 | * Copyright (c) 1983 Regents of the University of California. |
| 3 | * All rights reserved. | |
| 4 | * | |
| 5 | * Redistribution and use in source and binary forms are permitted | |
| 6 | * provided that this notice is preserved and that due credit is given | |
| 7 | * to the University of California at Berkeley. The name of the University | |
| 8 | * may not be used to endorse or promote products derived from this | |
| 9 | * software without specific prior written permission. This software | |
| 10 | * is provided ``as is'' without express or implied warranty. | |
| 60de5df9 EW |
11 | */ |
| 12 | ||
| 46e9ea25 KB |
13 | #ifndef lint |
| 14 | static char sccsid[] = "@(#)parser3.c 3.6 (Berkeley) %G%"; | |
| 15 | #endif /* not lint */ | |
| 16 | ||
| 6c6eaf9a EW |
17 | #include "parser.h" |
| 18 | ||
| 19 | /* | |
| 20 | * = | |
| 21 | * ? : | |
| 22 | * || | |
| 23 | * && | |
| 24 | * | | |
| 25 | * ^ | |
| 26 | * & | |
| 27 | * == != | |
| 28 | * <= >= | |
| 29 | * << >> | |
| 30 | * + - | |
| 31 | * * / % | |
| 32 | * unary - + ~ ! | |
| 33 | */ | |
| 34 | p_expr(v, flag) | |
| 35 | register struct value *v; | |
| 36 | char flag; | |
| 37 | { | |
| 38 | struct value t; | |
| 39 | int ret; | |
| 40 | ||
| 6c6eaf9a EW |
41 | if (p_expr0(&t, flag) < 0) |
| 42 | return -1; | |
| 43 | ||
| 44 | if (token != T_ASSIGN) { | |
| 45 | *v = t; | |
| 46 | return 0; | |
| 47 | } | |
| 48 | switch (t.v_type) { | |
| bb4a0c0b EW |
49 | case V_NUM: |
| 50 | p_error("%d: Not a variable.", t.v_num); | |
| 6c6eaf9a EW |
51 | case V_ERR: |
| 52 | t.v_str = 0; | |
| 53 | break; | |
| 6c6eaf9a EW |
54 | } |
| 55 | ret = p_assign(t.v_str, v, flag); | |
| 56 | if (t.v_str != 0) | |
| 57 | str_free(t.v_str); | |
| 58 | return ret; | |
| 59 | } | |
| 60 | ||
| 61 | /* | |
| 62 | * ? : | |
| 63 | */ | |
| 64 | p_expr0(v, flag) | |
| 65 | register struct value *v; | |
| 66 | char flag; | |
| 67 | { | |
| 68 | struct value t; | |
| 69 | char true; | |
| 70 | ||
| 71 | if (p_expr1(v, flag) < 0) | |
| 72 | return -1; | |
| 73 | if (token != T_QUEST) | |
| 74 | return 0; | |
| 75 | switch (v->v_type) { | |
| 76 | case V_NUM: | |
| 77 | true = v->v_num != 0; | |
| 78 | break; | |
| 79 | case V_STR: | |
| fbbe9777 | 80 | p_error("?: Numeric left operand required."); |
| 6c6eaf9a EW |
81 | str_free(v->v_str); |
| 82 | v->v_type = V_ERR; | |
| 83 | case V_ERR: | |
| 84 | flag = 0; | |
| 85 | break; | |
| 86 | } | |
| 87 | (void) s_gettok(); | |
| 88 | v->v_type = V_ERR; | |
| 89 | if ((flag && true ? p_expr1(v, 1) : p_expr1(&t, 0)) < 0) | |
| 90 | return -1; | |
| 91 | if (token != T_COLON) { | |
| 92 | val_free(*v); | |
| 93 | p_synerror(); | |
| 94 | return -1; | |
| 95 | } | |
| 96 | (void) s_gettok(); | |
| 97 | return flag && !true ? p_expr1(v, 1) : p_expr1(&t, 0); | |
| 98 | } | |
| 99 | ||
| 100 | /* | |
| 101 | * || | |
| 102 | */ | |
| 103 | p_expr1(v, flag) | |
| 104 | register struct value *v; | |
| 105 | char flag; | |
| 106 | { | |
| 107 | char true = 0; | |
| 108 | ||
| 109 | if (p_expr2(v, flag) < 0) | |
| 110 | return -1; | |
| 111 | if (token != T_OROR) | |
| 112 | return 0; | |
| 113 | for (;;) { | |
| 114 | switch (v->v_type) { | |
| 115 | case V_NUM: | |
| 116 | v->v_num = true = true || v->v_num != 0; | |
| 117 | break; | |
| 118 | case V_STR: | |
| fbbe9777 | 119 | p_error("||: Numeric operands required."); |
| 6c6eaf9a EW |
120 | str_free(v->v_str); |
| 121 | v->v_type = V_ERR; | |
| 122 | case V_ERR: | |
| 123 | flag = 0; | |
| 124 | break; | |
| 125 | } | |
| 126 | if (token != T_OROR) | |
| 127 | return 0; | |
| 128 | (void) s_gettok(); | |
| 129 | if (p_expr2(v, flag && !true) < 0) | |
| 130 | return -1; | |
| 131 | } | |
| 132 | } | |
| 133 | ||
| 134 | /* | |
| 135 | * && | |
| 136 | */ | |
| 137 | p_expr2(v, flag) | |
| 138 | register struct value *v; | |
| 139 | char flag; | |
| 140 | { | |
| 141 | char true = 1; | |
| 142 | ||
| 143 | if (p_expr3_10(3, v, flag) < 0) | |
| 144 | return -1; | |
| 145 | if (token != T_ANDAND) | |
| 146 | return 0; | |
| 147 | for (;;) { | |
| 148 | switch (v->v_type) { | |
| 149 | case V_NUM: | |
| 150 | v->v_num = true = true && v->v_num != 0; | |
| 151 | break; | |
| 152 | case V_STR: | |
| fbbe9777 | 153 | p_error("&&: Numeric operands required."); |
| 6c6eaf9a EW |
154 | str_free(v->v_str); |
| 155 | v->v_type = V_ERR; | |
| 156 | case V_ERR: | |
| 157 | flag = 0; | |
| 158 | break; | |
| 159 | } | |
| 160 | if (token != T_ANDAND) | |
| 161 | return 0; | |
| 162 | (void) s_gettok(); | |
| 163 | if (p_expr3_10(3, v, flag && true) < 0) | |
| 164 | return -1; | |
| 165 | } | |
| 166 | /*NOTREACHED*/ | |
| 167 | } |