Commit | Line | Data |
---|---|---|
4f027005 MT |
1 | %token ARITH_OR ARITH_AND ARITH_ADD ARITH_SUBT ARITH_MULT ARITH_DIV ARITH_REM ARITH_EQ ARITH_GT ARITH_GEQ ARITH_LT ARITH_LEQ ARITH_NEQ |
2 | %token ARITH_NUM ARITH_LPAREN ARITH_RPAREN ARITH_NOT ARITH_UNARYMINUS | |
3 | ||
4 | %left ARITH_OR | |
5 | %left ARITH_AND | |
6 | %left ARITH_EQ ARITH_NEQ | |
7 | %left ARITH_LT ARITH_GT ARITH_GEQ ARITH_LEQ | |
8 | %left ARITH_ADD ARITH_SUBT | |
9 | %left ARITH_MULT ARITH_DIV ARITH_REM | |
10 | %left ARITH_UNARYMINUS ARITH_NOT | |
11 | %% | |
12 | ||
13 | exp: expr = { | |
14 | return ($1); | |
15 | } | |
16 | ; | |
17 | ||
18 | ||
19 | expr: ARITH_LPAREN expr ARITH_RPAREN = { $$ = $2; } | |
20 | | expr ARITH_OR expr = { $$ = $1 ? $1 : $3 ? $3 : 0; } | |
21 | | expr ARITH_AND expr = { $$ = $1 ? ( $3 ? $3 : 0 ) : 0; } | |
22 | | expr ARITH_EQ expr = { $$ = $1 == $3; } | |
23 | | expr ARITH_GT expr = { $$ = $1 > $3; } | |
24 | | expr ARITH_GEQ expr = { $$ = $1 >= $3; } | |
25 | | expr ARITH_LT expr = { $$ = $1 < $3; } | |
26 | | expr ARITH_LEQ expr = { $$ = $1 <= $3; } | |
27 | | expr ARITH_NEQ expr = { $$ = $1 != $3; } | |
28 | | expr ARITH_ADD expr = { $$ = $1 + $3; } | |
29 | | expr ARITH_SUBT expr = { $$ = $1 - $3; } | |
30 | | expr ARITH_MULT expr = { $$ = $1 * $3; } | |
31 | | expr ARITH_DIV expr = { | |
32 | if ($3 == 0) | |
33 | yyerror("division by zero"); | |
34 | $$ = $1 / $3; | |
35 | } | |
36 | | expr ARITH_REM expr = { $$ = $1 % $3; } | |
37 | | ARITH_NOT expr = { $$ = !($2); } | |
38 | | ARITH_UNARYMINUS expr = { $$ = -($2); } | |
39 | | ARITH_NUM | |
40 | ; | |
41 | %% | |
42 | ||
43 | #include "shell.h" | |
44 | #include "error.h" | |
45 | #include "output.h" | |
46 | #include "memalloc.h" | |
47 | ||
48 | char *arith_buf, *arith_startbuf; | |
49 | ||
50 | arith(s) | |
51 | char *s; | |
52 | { | |
53 | extern arith_wasoper; | |
54 | long result; | |
55 | ||
56 | arith_wasoper = 1; | |
57 | arith_buf = arith_startbuf = s; | |
58 | ||
59 | INTOFF; | |
60 | result = yyparse(); | |
61 | arith_lex_reset(); /* reprime lex */ | |
62 | INTON; | |
63 | ||
64 | return (result); | |
65 | } | |
66 | ||
67 | yyerror(s) | |
68 | char *s; | |
69 | { | |
70 | extern yytext, yylval; | |
71 | ||
72 | yyerrok; | |
73 | yyclearin; | |
74 | arith_lex_reset(); /* reprime lex */ | |
75 | error("arithmetic expression: %s: \"%s\"", s, arith_startbuf); | |
76 | } | |
77 | ||
78 | /* | |
79 | * The exp(1) builtin. | |
80 | */ | |
81 | expcmd(argc, argv) | |
82 | char **argv; | |
83 | { | |
84 | char *p; | |
85 | char *concat; | |
86 | char **ap; | |
87 | long i; | |
88 | ||
89 | if (argc > 1) { | |
90 | p = argv[1]; | |
91 | if (argc > 2) { | |
92 | /* | |
93 | * concatenate arguments | |
94 | */ | |
95 | STARTSTACKSTR(concat); | |
96 | ap = argv + 2; | |
97 | for (;;) { | |
98 | while (*p) | |
99 | STPUTC(*p++, concat); | |
100 | if ((p = *ap++) == NULL) | |
101 | break; | |
102 | STPUTC(' ', concat); | |
103 | } | |
104 | STPUTC('\0', concat); | |
105 | p = grabstackstr(concat); | |
106 | } | |
107 | } else | |
108 | p = ""; | |
109 | ||
110 | i = arith(p); | |
111 | ||
112 | out1fmt("%d\n", i); | |
113 | return (! i); | |
114 | } | |
115 | ||
116 | /*************************/ | |
117 | #ifdef TEST_ARITH | |
118 | #include <stdio.h> | |
119 | main(argc, argv) | |
120 | char *argv[]; | |
121 | { | |
122 | printf("%d\n", exp(argv[1])); | |
123 | } | |
124 | error(s) | |
125 | char *s; | |
126 | { | |
127 | fprintf(stderr, "exp: %s\n", s); | |
128 | exit(1); | |
129 | } | |
130 | #endif |