freebsd-nq/lib/libc/stdio/open_wmemstream.c
Enji Cooper c6e615506b Use stdint.h instead of inttypes.h as the latter pollutes namespace more
MFC after: 3 days
X-MFC with: r292004
Submitted by: bde
Sponsored by: EMC / Isilon Storage Division
2015-12-09 09:14:57 +00:00

275 lines
6.3 KiB
C

/*-
* Copyright (c) 2013 Hudson River Trading LLC
* Written by: John H. Baldwin <jhb@FreeBSD.org>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include "namespace.h"
#include <assert.h>
#include <errno.h>
#include <limits.h>
#ifdef DEBUG
#include <stdint.h>
#endif
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <wchar.h>
#include "un-namespace.h"
/* XXX: There is no FPOS_MAX. This assumes fpos_t is an off_t. */
#define FPOS_MAX OFF_MAX
struct wmemstream {
wchar_t **bufp;
size_t *sizep;
ssize_t len;
fpos_t offset;
mbstate_t mbstate;
};
static int
wmemstream_grow(struct wmemstream *ms, fpos_t newoff)
{
wchar_t *buf;
ssize_t newsize;
if (newoff < 0 || newoff >= SSIZE_MAX / sizeof(wchar_t))
newsize = SSIZE_MAX / sizeof(wchar_t) - 1;
else
newsize = newoff;
if (newsize > ms->len) {
buf = realloc(*ms->bufp, (newsize + 1) * sizeof(wchar_t));
if (buf != NULL) {
#ifdef DEBUG
fprintf(stderr, "WMS: %p growing from %zd to %zd\n",
ms, ms->len, newsize);
#endif
wmemset(buf + ms->len + 1, 0, newsize - ms->len);
*ms->bufp = buf;
ms->len = newsize;
return (1);
}
return (0);
}
return (1);
}
static void
wmemstream_update(struct wmemstream *ms)
{
assert(ms->len >= 0 && ms->offset >= 0);
*ms->sizep = ms->len < ms->offset ? ms->len : ms->offset;
}
/*
* Based on a starting multibyte state and an input buffer, determine
* how many wchar_t's would be output. This doesn't use mbsnrtowcs()
* so that it can handle embedded null characters.
*/
static size_t
wbuflen(const mbstate_t *state, const char *buf, int len)
{
mbstate_t lenstate;
size_t charlen, count;
count = 0;
lenstate = *state;
while (len > 0) {
charlen = mbrlen(buf, len, &lenstate);
if (charlen == (size_t)-1)
return (-1);
if (charlen == (size_t)-2)
break;
if (charlen == 0)
/* XXX: Not sure how else to handle this. */
charlen = 1;
len -= charlen;
buf += charlen;
count++;
}
return (count);
}
static int
wmemstream_write(void *cookie, const char *buf, int len)
{
struct wmemstream *ms;
ssize_t consumed, wlen;
size_t charlen;
ms = cookie;
wlen = wbuflen(&ms->mbstate, buf, len);
if (wlen < 0) {
errno = EILSEQ;
return (-1);
}
if (!wmemstream_grow(ms, ms->offset + wlen))
return (-1);
/*
* This copies characters one at a time rather than using
* mbsnrtowcs() so it can properly handle embedded null
* characters.
*/
consumed = 0;
while (len > 0 && ms->offset < ms->len) {
charlen = mbrtowc(*ms->bufp + ms->offset, buf, len,
&ms->mbstate);
if (charlen == (size_t)-1) {
if (consumed == 0) {
errno = EILSEQ;
return (-1);
}
/* Treat it as a successful short write. */
break;
}
if (charlen == 0)
/* XXX: Not sure how else to handle this. */
charlen = 1;
if (charlen == (size_t)-2) {
consumed += len;
len = 0;
} else {
consumed += charlen;
buf += charlen;
len -= charlen;
ms->offset++;
}
}
wmemstream_update(ms);
#ifdef DEBUG
fprintf(stderr, "WMS: write(%p, %d) = %zd\n", ms, len, consumed);
#endif
return (consumed);
}
static fpos_t
wmemstream_seek(void *cookie, fpos_t pos, int whence)
{
struct wmemstream *ms;
fpos_t old;
ms = cookie;
old = ms->offset;
switch (whence) {
case SEEK_SET:
/* _fseeko() checks for negative offsets. */
assert(pos >= 0);
ms->offset = pos;
break;
case SEEK_CUR:
/* This is only called by _ftello(). */
assert(pos == 0);
break;
case SEEK_END:
if (pos < 0) {
if (pos + ms->len < 0) {
#ifdef DEBUG
fprintf(stderr,
"WMS: bad SEEK_END: pos %jd, len %zd\n",
(intmax_t)pos, ms->len);
#endif
errno = EINVAL;
return (-1);
}
} else {
if (FPOS_MAX - ms->len < pos) {
#ifdef DEBUG
fprintf(stderr,
"WMS: bad SEEK_END: pos %jd, len %zd\n",
(intmax_t)pos, ms->len);
#endif
errno = EOVERFLOW;
return (-1);
}
}
ms->offset = ms->len + pos;
break;
}
/* Reset the multibyte state if a seek changes the position. */
if (ms->offset != old)
memset(&ms->mbstate, 0, sizeof(ms->mbstate));
wmemstream_update(ms);
#ifdef DEBUG
fprintf(stderr, "WMS: seek(%p, %jd, %d) %jd -> %jd\n", ms,
(intmax_t)pos, whence, (intmax_t)old, (intmax_t)ms->offset);
#endif
return (ms->offset);
}
static int
wmemstream_close(void *cookie)
{
free(cookie);
return (0);
}
FILE *
open_wmemstream(wchar_t **bufp, size_t *sizep)
{
struct wmemstream *ms;
int save_errno;
FILE *fp;
if (bufp == NULL || sizep == NULL) {
errno = EINVAL;
return (NULL);
}
*bufp = calloc(1, sizeof(wchar_t));
if (*bufp == NULL)
return (NULL);
ms = malloc(sizeof(*ms));
if (ms == NULL) {
save_errno = errno;
free(*bufp);
*bufp = NULL;
errno = save_errno;
return (NULL);
}
ms->bufp = bufp;
ms->sizep = sizep;
ms->len = 0;
ms->offset = 0;
memset(&ms->mbstate, 0, sizeof(mbstate_t));
wmemstream_update(ms);
fp = funopen(ms, NULL, wmemstream_write, wmemstream_seek,
wmemstream_close);
if (fp == NULL) {
save_errno = errno;
free(ms);
free(*bufp);
*bufp = NULL;
errno = save_errno;
return (NULL);
}
fwide(fp, 1);
return (fp);
}