freebsd-skq/lib/libc/stdio/open_wmemstream.c
pfg 9014a6e40c libc: further adoption of SPDX licensing ID tags.
Mainly focus on files that use BSD 2-Clause license, however the tool I
was using mis-identified many licenses so this was mostly a manual - error
prone - task.

The Software Package Data Exchange (SPDX) group provides a specification
to make it easier for automated tools to detect and summarize well known
opensource licenses. We are gradually adopting the specification, noting
that the tags are considered only advisory and do not, in any way,
superceed or replace the license texts.
2017-11-25 17:12:48 +00:00

277 lines
6.3 KiB
C

/*-
* SPDX-License-Identifier: BSD-2-Clause-FreeBSD
*
* 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 = reallocarray(*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);
}