1 #include <u.h>
2 #include <libc.h>
3 #include <stdio.h>
4 
5 /*
6  * try all combination of flags and float conversions
7  * with some different widths & precisions
8  */
9 
10 #define Njust 2
11 #define Nplus 3
12 #define Nalt 2
13 #define Nzero 2
14 #define Nspec 5
15 #define Nwidth 5
16 #define Nprec 5
17 
18 static double fmtvals[] = {
19 	3.1415925535897932e15,
20 	3.1415925535897932e14,
21 	3.1415925535897932e13,
22 	3.1415925535897932e12,
23 	3.1415925535897932e11,
24 	3.1415925535897932e10,
25 	3.1415925535897932e9,
26 	3.1415925535897932e8,
27 	3.1415925535897932e7,
28 	3.1415925535897932e6,
29 	3.1415925535897932e5,
30 	3.1415925535897932e4,
31 	3.1415925535897932e3,
32 	3.1415925535897932e2,
33 	3.1415925535897932e1,
34 	3.1415925535897932e0,
35 	3.1415925535897932e-1,
36 	3.1415925535897932e-2,
37 	3.1415925535897932e-3,
38 	3.1415925535897932e-4,
39 	3.1415925535897932e-5,
40 	3.1415925535897932e-6,
41 	3.1415925535897932e-7,
42 	3.1415925535897932e-8,
43 	3.1415925535897932e-9,
44 	3.1415925535897932e-10,
45 	3.1415925535897932e-11,
46 	3.1415925535897932e-12,
47 	3.1415925535897932e-13,
48 	3.1415925535897932e-14,
49 	3.1415925535897932e-15,
50 };
51 
52 /*
53  * are the numbers close?
54  * used to compare long numbers where the last few digits are garbage
55  * due to precision problems
56  */
57 static int
58 numclose(char *num1, char *num2)
59 {
60 	int ndig;
61 	double d1, d2;
62 	enum { MAXDIG = 15 };
63 
64 	d1 = fmtstrtod(num1, 0);
65 	d2 = fmtstrtod(num2, 0);
66 	if(d1 != d2)
67 		return 0;
68 
69 	ndig = 0;
70 	while (*num1) {
71 		if (*num1 >= '0' && *num1 <= '9') {
72 			ndig++;
73 			if (ndig > MAXDIG) {
74 				if (!(*num2 >= '0' && *num2 <= '9')) {
75 					return 0;
76 				}
77 			} else if (*num1 != *num2) {
78 				return 0;
79 			}
80 		} else if (*num1 != *num2) {
81 			return 0;
82 		} else if (*num1 == 'e' || *num1 == 'E') {
83 			ndig = 0;
84 		}
85 		num1++;
86 		num2++;
87 	}
88 	if (*num1 || !num2)
89 		return 0;
90 	return 1;
91 }
92 
93 static void
94 doit(int just, int plus, int alt, int zero, int width, int prec, int spec)
95 {
96 	char format[256];
97 	char *p;
98 	const char *s;
99 	int i;
100 
101 	p = format;
102 	*p++ = '%';
103 	if (just > 0)
104 		*p++ = "-"[just - 1];
105 	if (plus > 0)
106 		*p++ = "+ "[plus - 1];
107 	if (alt > 0)
108 		*p++ = "#"[alt - 1];
109 	if (zero > 0)
110 		*p++ = "0"[zero - 1];
111 
112 	s = "";
113 	switch (width) {
114 	case 1: s = "1"; break;
115 	case 2: s = "5"; break;
116 	case 3: s = "10"; break;
117 	case 4: s = "15"; break;
118 	}
119 	strcpy(p, s);
120 
121 	s = "";
122 	switch (prec) {
123 	case 1: s = ".0"; break;
124 	case 2: s = ".2"; break;
125 	case 3: s = ".5"; break;
126 	case 4: s = ".15"; break;
127 	}
128 	strcat(p, s);
129 
130 	p = strchr(p, '\0');
131 	*p++ = "efgEG"[spec];
132 	*p = '\0';
133 
134 	for (i = 0; i < sizeof(fmtvals) / sizeof(fmtvals[0]); i++) {
135 		char ref[1024], buf[1024];
136 		Rune rbuf[1024];
137 		double d1, d2;
138 
139 		sprintf(ref, format, fmtvals[i]);
140 		snprint(buf, sizeof(buf), format, fmtvals[i]);
141 		if (strcmp(ref, buf) != 0
142 		&& !numclose(ref, buf)) {
143 			d1 = fmtstrtod(ref, 0);
144 			d2 = fmtstrtod(buf, 0);
145 			fprintf(stderr, "%s: ref='%s'%s fmt='%s'%s\n",
146 				format,
147 				ref, d1==fmtvals[i] ? "" : " (ref is inexact!)",
148 				buf, d2==fmtvals[i] ? "" : " (fmt is inexact!)");
149 		//	exits("oops");
150 		}
151 
152 		/* Check again with output to rune string */
153 		runesnprint(rbuf, 1024, format, fmtvals[i]);
154 		snprint(buf, sizeof(buf), "%S", rbuf);
155 		if (strcmp(ref, buf) != 0
156 		&& !numclose(ref, buf)) {
157 			d1 = fmtstrtod(ref, 0);
158 			d2 = fmtstrtod(buf, 0);
159 			fprintf(stderr, "%s: ref='%s'%s fmt='%s'%s\n",
160 				format,
161 				ref, d1==fmtvals[i] ? "" : " (ref is inexact!)",
162 				buf, d2==fmtvals[i] ? "" : " (fmt is inexact!)");
163 		//	exits("oops");
164 		}
165 	}
166 }
167 
168 void
169 main(int argc, char **argv)
170 {
171 	int just, plus, alt, zero, width, prec, spec;
172 
173 	for (just = 0; just < Njust; just++)
174 	for (plus = 0; plus < Nplus; plus++)
175 	for (alt = 0; alt < Nalt; alt++)
176 	for (zero = 0; zero < Nzero; zero++)
177 	for (width = 0; width < Nwidth; width++)
178 	for (prec = 0; prec < Nprec; prec++)
179 	for (spec = 0; spec < Nspec; spec++)
180 		doit(just, plus, alt, zero, width, prec, spec);
181 
182 	exits(0);
183 }