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
9struct 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
19struct wms_FILE {
20 FILE f;
21 struct cookie c;
22 unsigned char buf[1];
23};
24
25static 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) {
30fail:
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
40static size_t wms_write(FILE *f, const unsigned char *buf, size_t len)
41{
42 struct cookie *c = f->cookie;
43 size_t len2 = f->wpos - f->wbase;
44 wchar_t *newbuf;
45 if (len2) {
46 f->wpos = f->wbase;
47 if (wms_write(f, f->wbase, len2) < len2) return 0;
48 }
49 if (len + c->pos >= c->space) {
50 len2 = 2*c->space+1 | c->pos+len+1;
51 if (len2 > SSIZE_MAX/4) return 0;
52 newbuf = realloc(c->buf, len2*4);
53 if (!newbuf) return 0;
54 *c->bufp = c->buf = newbuf;
55 memset(c->buf + c->space, 0, 4*(len2 - c->space));
56 c->space = len2;
57 }
58
59 len2 = mbsnrtowcs(c->buf+c->pos, (void *)&buf, len, c->space-c->pos, &c->mbs);
60 if (len2 == -1) return 0;
61 c->pos += len2;
62 if (c->pos >= c->len) c->len = c->pos;
63 *c->sizep = c->pos;
64 return len;
65}
66
67static int wms_close(FILE *f)
68{
69 return 0;
70}
71
72FILE *open_wmemstream(wchar_t **bufp, size_t *sizep)
73{
74 struct wms_FILE *f;
75 wchar_t *buf;
76
77 if (!(f=malloc(sizeof *f))) return 0;
78 if (!(buf=malloc(sizeof *buf))) {
79 free(f);
80 return 0;
81 }
82 memset(&f->f, 0, sizeof f->f);
83 memset(&f->c, 0, sizeof f->c);
84 f->f.cookie = &f->c;
85
86 f->c.bufp = bufp;
87 f->c.sizep = sizep;
88 f->c.pos = f->c.len = f->c.space = *sizep = 0;
89 f->c.buf = *bufp = buf;
90 *buf = 0;
91
92 f->f.flags = F_NORD;
93 f->f.fd = -1;
94 f->f.buf = f->buf;
95 f->f.buf_size = 0;
96 f->f.lbf = EOF;
97 f->f.write = wms_write;
98 f->f.seek = wms_seek;
99 f->f.close = wms_close;
100
101 if (!libc.threaded) f->f.lock = -1;
102
103 fwide(&f->f, 1);
104
105 return __ofl_add(&f->f);
106}