projects / unix-history / blame
| Commit | Line | Data |
|---|---|---|
| 6c6eaf9a EW |
1 | #ifndef lint |
| 2 | static char *sccsid = "@(#)parser3.c 3.1 84/01/12"; | |
| 3 | #endif | |
| 4 | ||
| 5 | #include "parser.h" | |
| 6 | ||
| 7 | /* | |
| 8 | * = | |
| 9 | * ? : | |
| 10 | * || | |
| 11 | * && | |
| 12 | * | | |
| 13 | * ^ | |
| 14 | * & | |
| 15 | * == != | |
| 16 | * <= >= | |
| 17 | * << >> | |
| 18 | * + - | |
| 19 | * * / % | |
| 20 | * unary - + ~ ! | |
| 21 | */ | |
| 22 | p_expr(v, flag) | |
| 23 | register struct value *v; | |
| 24 | char flag; | |
| 25 | { | |
| 26 | struct value t; | |
| 27 | int ret; | |
| 28 | ||
| 29 | #ifdef DEBUG | |
| 30 | error("expr: %d.", flag); | |
| 31 | #endif | |
| 32 | if (p_expr0(&t, flag) < 0) | |
| 33 | return -1; | |
| 34 | ||
| 35 | if (token != T_ASSIGN) { | |
| 36 | *v = t; | |
| 37 | return 0; | |
| 38 | } | |
| 39 | switch (t.v_type) { | |
| 40 | case V_ERR: | |
| 41 | t.v_str = 0; | |
| 42 | break; | |
| 43 | case V_NUM: | |
| 44 | if ((t.v_str = str_itoa(t.v_num)) == 0) { | |
| 45 | p_memerror(); | |
| 46 | return -1; | |
| 47 | } | |
| 48 | } | |
| 49 | ret = p_assign(t.v_str, v, flag); | |
| 50 | if (t.v_str != 0) | |
| 51 | str_free(t.v_str); | |
| 52 | return ret; | |
| 53 | } | |
| 54 | ||
| 55 | /* | |
| 56 | * ? : | |
| 57 | */ | |
| 58 | p_expr0(v, flag) | |
| 59 | register struct value *v; | |
| 60 | char flag; | |
| 61 | { | |
| 62 | struct value t; | |
| 63 | char true; | |
| 64 | ||
| 65 | if (p_expr1(v, flag) < 0) | |
| 66 | return -1; | |
| 67 | if (token != T_QUEST) | |
| 68 | return 0; | |
| 69 | switch (v->v_type) { | |
| 70 | case V_NUM: | |
| 71 | true = v->v_num != 0; | |
| 72 | break; | |
| 73 | case V_STR: | |
| 74 | p_error("Numeric value required for ?."); | |
| 75 | str_free(v->v_str); | |
| 76 | v->v_type = V_ERR; | |
| 77 | case V_ERR: | |
| 78 | flag = 0; | |
| 79 | break; | |
| 80 | } | |
| 81 | (void) s_gettok(); | |
| 82 | v->v_type = V_ERR; | |
| 83 | if ((flag && true ? p_expr1(v, 1) : p_expr1(&t, 0)) < 0) | |
| 84 | return -1; | |
| 85 | if (token != T_COLON) { | |
| 86 | val_free(*v); | |
| 87 | p_synerror(); | |
| 88 | return -1; | |
| 89 | } | |
| 90 | (void) s_gettok(); | |
| 91 | return flag && !true ? p_expr1(v, 1) : p_expr1(&t, 0); | |
| 92 | } | |
| 93 | ||
| 94 | /* | |
| 95 | * || | |
| 96 | */ | |
| 97 | p_expr1(v, flag) | |
| 98 | register struct value *v; | |
| 99 | char flag; | |
| 100 | { | |
| 101 | char true = 0; | |
| 102 | ||
| 103 | if (p_expr2(v, flag) < 0) | |
| 104 | return -1; | |
| 105 | if (token != T_OROR) | |
| 106 | return 0; | |
| 107 | for (;;) { | |
| 108 | switch (v->v_type) { | |
| 109 | case V_NUM: | |
| 110 | v->v_num = true = true || v->v_num != 0; | |
| 111 | break; | |
| 112 | case V_STR: | |
| 113 | p_error("Numeric value required for ||."); | |
| 114 | str_free(v->v_str); | |
| 115 | v->v_type = V_ERR; | |
| 116 | case V_ERR: | |
| 117 | flag = 0; | |
| 118 | break; | |
| 119 | } | |
| 120 | if (token != T_OROR) | |
| 121 | return 0; | |
| 122 | (void) s_gettok(); | |
| 123 | if (p_expr2(v, flag && !true) < 0) | |
| 124 | return -1; | |
| 125 | } | |
| 126 | } | |
| 127 | ||
| 128 | /* | |
| 129 | * && | |
| 130 | */ | |
| 131 | p_expr2(v, flag) | |
| 132 | register struct value *v; | |
| 133 | char flag; | |
| 134 | { | |
| 135 | char true = 1; | |
| 136 | ||
| 137 | if (p_expr3_10(3, v, flag) < 0) | |
| 138 | return -1; | |
| 139 | if (token != T_ANDAND) | |
| 140 | return 0; | |
| 141 | for (;;) { | |
| 142 | switch (v->v_type) { | |
| 143 | case V_NUM: | |
| 144 | v->v_num = true = true && v->v_num != 0; | |
| 145 | break; | |
| 146 | case V_STR: | |
| 147 | p_error("Numeric value required for &&."); | |
| 148 | str_free(v->v_str); | |
| 149 | v->v_type = V_ERR; | |
| 150 | case V_ERR: | |
| 151 | flag = 0; | |
| 152 | break; | |
| 153 | } | |
| 154 | if (token != T_ANDAND) | |
| 155 | return 0; | |
| 156 | (void) s_gettok(); | |
| 157 | if (p_expr3_10(3, v, flag && true) < 0) | |
| 158 | return -1; | |
| 159 | } | |
| 160 | /*NOTREACHED*/ | |
| 161 | } |