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authorDenys Vlasenko <vda.linux@googlemail.com>2010-07-29 04:00:27 +0200
committerDenys Vlasenko <vda.linux@googlemail.com>2010-07-29 04:00:27 +0200
commit7a07b0ee6a99a98ec1f144d5d06043fa0c03f451 (patch)
tree0978bd98b9fd690c71f2a8ca06f02e0b65039ce4 /miscutils/dc.c
parent416f0405cb03ecc816b829d5a3d357a556b95fcd (diff)
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dc: make it use long longs for integer ops
function old new delta print_base 176 238 +62 or 91 103 +12 eor 91 103 +12 and 91 103 +12 not 60 64 +4 mod 103 105 +2 ------------------------------------------------------------------------------ (add/remove: 0/0 grow/shrink: 6/0 up/down: 104/0) Total: 104 bytes Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Diffstat (limited to 'miscutils/dc.c')
-rw-r--r--miscutils/dc.c65
1 files changed, 51 insertions, 14 deletions
diff --git a/miscutils/dc.c b/miscutils/dc.c
index cb4b1e9b1..ebf357281 100644
--- a/miscutils/dc.c
+++ b/miscutils/dc.c
@@ -6,7 +6,39 @@
6#include "libbb.h" 6#include "libbb.h"
7#include <math.h> 7#include <math.h>
8 8
9/* Tiny RPN calculator, because "expr" didn't give me bitwise operations. */ 9//usage:#define dc_trivial_usage
10//usage: "expression..."
11//usage:
12//usage:#define dc_full_usage "\n\n"
13//usage: "Tiny RPN calculator. Operations:\n"
14//usage: "+, add, -, sub, *, mul, /, div, %, mod, **, exp, and, or, not, eor,\n"
15//usage: "p - print top of the stack (without popping),\n"
16//usage: "f - print entire stack, o - pop the value and set output radix\n"
17//usage: "(value must be 10, 16, 8 or 2).\n"
18//usage: "Examples: 'dc 2 2 add' -> 4, 'dc 8 8 * 2 2 + /' -> 16\n"
19//usage:
20//usage:#define dc_example_usage
21//usage: "$ dc 2 2 + p\n"
22//usage: "4\n"
23//usage: "$ dc 8 8 \\* 2 2 + / p\n"
24//usage: "16\n"
25//usage: "$ dc 0 1 and p\n"
26//usage: "0\n"
27//usage: "$ dc 0 1 or p\n"
28//usage: "1\n"
29//usage: "$ echo 72 9 div 8 mul p | dc\n"
30//usage: "64\n"
31
32#if 0
33typedef unsigned data_t;
34#define DATA_FMT ""
35#elif 0
36typedef unsigned long data_t;
37#define DATA_FMT "l"
38#else
39typedef unsigned long long data_t;
40#define DATA_FMT "ll"
41#endif
10 42
11 43
12struct globals { 44struct globals {
@@ -73,29 +105,29 @@ static void divide(void)
73 105
74static void mod(void) 106static void mod(void)
75{ 107{
76 unsigned d = pop(); 108 data_t d = pop();
77 109
78 push((unsigned) pop() % d); 110 push((data_t) pop() % d);
79} 111}
80 112
81static void and(void) 113static void and(void)
82{ 114{
83 push((unsigned) pop() & (unsigned) pop()); 115 push((data_t) pop() & (data_t) pop());
84} 116}
85 117
86static void or(void) 118static void or(void)
87{ 119{
88 push((unsigned) pop() | (unsigned) pop()); 120 push((data_t) pop() | (data_t) pop());
89} 121}
90 122
91static void eor(void) 123static void eor(void)
92{ 124{
93 push((unsigned) pop() ^ (unsigned) pop()); 125 push((data_t) pop() ^ (data_t) pop());
94} 126}
95 127
96static void not(void) 128static void not(void)
97{ 129{
98 push(~(unsigned) pop()); 130 push(~(data_t) pop());
99} 131}
100 132
101static void set_output_base(void) 133static void set_output_base(void)
@@ -112,25 +144,30 @@ static void set_output_base(void)
112 144
113static void print_base(double print) 145static void print_base(double print)
114{ 146{
115 unsigned x, i; 147 data_t x, i;
116 148
149 x = (data_t) print;
117 if (base == 10) { 150 if (base == 10) {
118 printf("%g\n", print); 151 if (x == print) /* exactly representable as unsigned integer */
152 printf("%"DATA_FMT"u\n", x);
153 else
154 printf("%g\n", print);
119 return; 155 return;
120 } 156 }
121 157
122 x = (unsigned)print;
123 switch (base) { 158 switch (base) {
124 case 16: 159 case 16:
125 printf("%x\n", x); 160 printf("%"DATA_FMT"x\n", x);
126 break; 161 break;
127 case 8: 162 case 8:
128 printf("%o\n", x); 163 printf("%"DATA_FMT"o\n", x);
129 break; 164 break;
130 default: /* base 2 */ 165 default: /* base 2 */
131 i = (unsigned)INT_MAX + 1; 166 i = MAXINT(data_t) - (MAXINT(data_t) >> 1);
167 /* i is 100000...00000 */
132 do { 168 do {
133 if (x & i) break; 169 if (x & i)
170 break;
134 i >>= 1; 171 i >>= 1;
135 } while (i > 1); 172 } while (i > 1);
136 do { 173 do {