1 #include "floatscan.h"
2 #include "shgetc.h"
3 #include "stdio_impl.h"
4 #include <wchar.h>
5 #include <wctype.h>
6 
7 /* This read function heavily cheats. It knows:
8  *  (1) len will always be 1
9  *  (2) non-ascii characters don't matter */
10 
do_read(FILE * f,unsigned char * buf,size_t len)11 static size_t do_read(FILE* f, unsigned char* buf, size_t len) {
12     size_t i;
13     const wchar_t* wcs = f->cookie;
14 
15     if (!wcs[0])
16         wcs = L"@";
17     for (i = 0; i < f->buf_size && wcs[i]; i++)
18         f->buf[i] = wcs[i] < 128 ? wcs[i] : '@';
19     f->rpos = f->buf;
20     f->rend = f->buf + i;
21     f->cookie = (void*)(wcs + i);
22 
23     if (i && len) {
24         *buf = *f->rpos++;
25         return 1;
26     }
27     return 0;
28 }
29 
wcstox(const wchar_t * s,wchar_t ** p,int prec)30 static long double wcstox(const wchar_t* s, wchar_t** p, int prec) {
31     wchar_t* t = (wchar_t*)s;
32     unsigned char buf[64];
33     FILE f = {};
34     f.flags = 0;
35     f.rpos = f.rend = 0;
36     f.buf = buf + 4;
37     f.buf_size = sizeof buf - 4;
38     f.lock = -1;
39     f.read = do_read;
40     while (iswspace(*t))
41         t++;
42     f.cookie = (void*)t;
43     shlim(&f, 0);
44     long double y = __floatscan(&f, prec, 1);
45     if (p) {
46         size_t cnt = shcnt(&f);
47         *p = cnt ? t + cnt : (wchar_t*)s;
48     }
49     return y;
50 }
51 
wcstof(const wchar_t * restrict s,wchar_t ** restrict p)52 float wcstof(const wchar_t* restrict s, wchar_t** restrict p) {
53     return wcstox(s, p, 0);
54 }
55 
wcstod(const wchar_t * restrict s,wchar_t ** restrict p)56 double wcstod(const wchar_t* restrict s, wchar_t** restrict p) {
57     return wcstox(s, p, 1);
58 }
59 
wcstold(const wchar_t * restrict s,wchar_t ** restrict p)60 long double wcstold(const wchar_t* restrict s, wchar_t** restrict p) {
61     return wcstox(s, p, 2);
62 }
63