1#include <stdint.h>
2#include <wchar.h>
3#include <errno.h>
4#include <string.h>
5#include <stdlib.h>
6#include "internal.h"
7
8size_t mbsrtowcs(wchar_t *restrict ws, const char **restrict src, size_t wn, mbstate_t *restrict st)
9{
10 const unsigned char *s = (const void *)*src;
11 size_t wn0 = wn;
12 unsigned c = 0;
13
14 if (st && (c = *(unsigned *)st)) {
15 if (ws) {
16 *(unsigned *)st = 0;
17 goto resume;
18 } else {
19 goto resume0;
20 }
21 }
22
23 if (MB_CUR_MAX==1) {
24 if (!ws) return strlen((const char *)s);
25 for (;;) {
26 if (!wn) {
27 *src = (const void *)s;
28 return wn0;
29 }
30 if (!*s) break;
31 c = *s++;
32 *ws++ = CODEUNIT(c);
33 wn--;
34 }
35 *ws = 0;
36 *src = 0;
37 return wn0-wn;
38 }
39
40 if (!ws) for (;;) {
41#ifdef __GNUC__
42 typedef uint32_t __attribute__((__may_alias__)) w32;
43 if (*s-1u < 0x7f && (uintptr_t)s%4 == 0) {
44 while (!(( *(w32*)s | *(w32*)s-0x01010101) & 0x80808080)) {
45 s += 4;
46 wn -= 4;
47 }
48 }
49#endif
50 if (*s-1u < 0x7f) {
51 s++;
52 wn--;
53 continue;
54 }
55 if (*s-SA > SB-SA) break;
56 c = bittab[*s++-SA];
57resume0:
58 if (OOB(c,*s)) { s--; break; }
59 s++;
60 if (c&(1U<<25)) {
61 if (*s-0x80u >= 0x40) { s-=2; break; }
62 s++;
63 if (c&(1U<<19)) {
64 if (*s-0x80u >= 0x40) { s-=3; break; }
65 s++;
66 }
67 }
68 wn--;
69 c = 0;
70 } else for (;;) {
71 if (!wn) {
72 *src = (const void *)s;
73 return wn0;
74 }
75#ifdef __GNUC__
76 typedef uint32_t __attribute__((__may_alias__)) w32;
77 if (*s-1u < 0x7f && (uintptr_t)s%4 == 0) {
78 while (wn>=5 && !(( *(w32*)s | *(w32*)s-0x01010101) & 0x80808080)) {
79 *ws++ = *s++;
80 *ws++ = *s++;
81 *ws++ = *s++;
82 *ws++ = *s++;
83 wn -= 4;
84 }
85 }
86#endif
87 if (*s-1u < 0x7f) {
88 *ws++ = *s++;
89 wn--;
90 continue;
91 }
92 if (*s-SA > SB-SA) break;
93 c = bittab[*s++-SA];
94resume:
95 if (OOB(c,*s)) { s--; break; }
96 c = (c<<6) | *s++-0x80;
97 if (c&(1U<<31)) {
98 if (*s-0x80u >= 0x40) { s-=2; break; }
99 c = (c<<6) | *s++-0x80;
100 if (c&(1U<<31)) {
101 if (*s-0x80u >= 0x40) { s-=3; break; }
102 c = (c<<6) | *s++-0x80;
103 }
104 }
105 *ws++ = c;
106 wn--;
107 c = 0;
108 }
109
110 if (!c && !*s) {
111 if (ws) {
112 *ws = 0;
113 *src = 0;
114 }
115 return wn0-wn;
116 }
117 errno = EILSEQ;
118 if (ws) *src = (const void *)s;
119 return -1;
120}