1 #include "stdio_impl.h"
2 #include <wchar.h>
3 #include <errno.h>
4 #include <limits.h>
5 #include <string.h>
6 #include <stdlib.h>
7 #include "libc.h"
8
9 struct cookie {
10 wchar_t **bufp;
11 size_t *sizep;
12 size_t pos;
13 wchar_t *buf;
14 size_t len;
15 size_t space;
16 mbstate_t mbs;
17 };
18
19 struct wms_FILE {
20 FILE f;
21 struct cookie c;
22 unsigned char buf[1];
23 };
24
wms_seek(FILE * f,off_t off,int whence)25 static off_t wms_seek(FILE *f, off_t off, int whence)
26 {
27 ssize_t base;
28 struct cookie *c = f->cookie;
29 if (whence>2U) {
30 fail:
31 errno = EINVAL;
32 return -1;
33 }
34 base = (size_t [3]){0, c->pos, c->len}[whence];
35 if (off < -base || off > SSIZE_MAX/4-base) goto fail;
36 memset(&c->mbs, 0, sizeof c->mbs);
37 return c->pos = base+off;
38 }
39
wms_write(FILE * f,const unsigned char * buf,size_t len)40 static size_t wms_write(FILE *f, const unsigned char *buf, size_t len)
41 {
42 struct cookie *c = f->cookie;
43 size_t len2;
44 wchar_t *newbuf;
45 if (len + c->pos >= c->space) {
46 len2 = 2*c->space+1 | c->pos+len+1;
47 if (len2 > SSIZE_MAX/4) return 0;
48 newbuf = realloc(c->buf, len2*4);
49 if (!newbuf) return 0;
50 *c->bufp = c->buf = newbuf;
51 memset(c->buf + c->space, 0, 4*(len2 - c->space));
52 c->space = len2;
53 }
54
55 len2 = mbsnrtowcs(c->buf+c->pos, (void *)&buf, len, c->space-c->pos, &c->mbs);
56 if (len2 == -1) return 0;
57 c->pos += len2;
58 if (c->pos >= c->len) c->len = c->pos;
59 *c->sizep = c->pos;
60 return len;
61 }
62
wms_close(FILE * f)63 static int wms_close(FILE *f)
64 {
65 return 0;
66 }
67
open_wmemstream(wchar_t ** bufp,size_t * sizep)68 FILE *open_wmemstream(wchar_t **bufp, size_t *sizep)
69 {
70 struct wms_FILE *f;
71 wchar_t *buf;
72
73 if (!(f=malloc(sizeof *f))) return 0;
74 if (!(buf=malloc(sizeof *buf))) {
75 free(f);
76 return 0;
77 }
78 memset(&f->f, 0, sizeof f->f);
79 memset(&f->c, 0, sizeof f->c);
80 f->f.cookie = &f->c;
81
82 f->c.bufp = bufp;
83 f->c.sizep = sizep;
84 f->c.pos = f->c.len = f->c.space = *sizep = 0;
85 f->c.buf = *bufp = buf;
86 *buf = 0;
87
88 f->f.flags = F_NORD;
89 f->f.fd = -1;
90 f->f.buf = f->buf;
91 f->f.buf_size = 0;
92 f->f.lbf = EOF;
93 f->f.write = wms_write;
94 f->f.seek = wms_seek;
95 f->f.close = wms_close;
96
97 if (!libc.threaded) f->f.lock = -1;
98
99 fwide(&f->f, 1);
100
101 return __ofl_add(&f->f);
102 }
103