Handle invalid buffer pointers when count is zero.
[glibc/history.git] / wcsmbs / wcrtomb.c
blobaa51b6891b07bc837b4456bb44b8fa06b352beea
1 /* Copyright (C) 1996,1997,1998,2000,2002,2005 Free Software Foundation, Inc.
2 This file is part of the GNU C Library.
3 Contributed by Ulrich Drepper <drepper@cygnus.com>, 1996.
5 The GNU C Library is free software; you can redistribute it and/or
6 modify it under the terms of the GNU Lesser General Public
7 License as published by the Free Software Foundation; either
8 version 2.1 of the License, or (at your option) any later version.
10 The GNU C Library is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 Lesser General Public License for more details.
15 You should have received a copy of the GNU Lesser General Public
16 License along with the GNU C Library; if not, write to the Free
17 Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
18 02111-1307 USA. */
20 #include <assert.h>
21 #include <dlfcn.h>
22 #include <errno.h>
23 #include <gconv.h>
24 #include <stdlib.h>
25 #include <wchar.h>
26 #include <wcsmbsload.h>
28 #include <sysdep.h>
30 #ifndef EILSEQ
31 # define EILSEQ EINVAL
32 #endif
35 /* This is the private state used if PS is NULL. */
36 static mbstate_t state;
38 size_t
39 __wcrtomb (char *s, wchar_t wc, mbstate_t *ps)
41 char buf[MB_CUR_MAX];
42 struct __gconv_step_data data;
43 int status;
44 size_t result;
45 size_t dummy;
46 const struct gconv_fcts *fcts;
48 /* Set information for this step. */
49 data.__invocation_counter = 0;
50 data.__internal_use = 1;
51 data.__flags = __GCONV_IS_LAST;
52 data.__statep = ps ?: &state;
53 data.__trans = NULL;
55 /* A first special case is if S is NULL. This means put PS in the
56 initial state. */
57 if (s == NULL)
59 s = buf;
60 wc = L'\0';
63 /* Tell where we want to have the result. */
64 data.__outbuf = (unsigned char *) s;
65 data.__outbufend = (unsigned char *) s + MB_CUR_MAX;
67 /* Get the conversion functions. */
68 fcts = get_gconv_fcts (_NL_CURRENT_DATA (LC_CTYPE));
69 __gconv_fct fct = fcts->tomb->__fct;
70 #ifdef PTR_DEMANGLE
71 if (fcts->tomb->__shlib_handle != NULL)
72 PTR_DEMANGLE (fct);
73 #endif
75 /* If WC is the NUL character we write into the output buffer the byte
76 sequence necessary for PS to get into the initial state, followed
77 by a NUL byte. */
78 if (wc == L'\0')
80 status = DL_CALL_FCT (fct, (fcts->tomb, &data, NULL, NULL,
81 NULL, &dummy, 1, 1));
83 if (status == __GCONV_OK || status == __GCONV_EMPTY_INPUT)
84 *data.__outbuf++ = '\0';
86 else
88 /* Do a normal conversion. */
89 const unsigned char *inbuf = (const unsigned char *) &wc;
91 status = DL_CALL_FCT (fct,
92 (fcts->tomb, &data, &inbuf,
93 inbuf + sizeof (wchar_t), NULL, &dummy, 0, 1));
96 /* There must not be any problems with the conversion but illegal input
97 characters. The output buffer must be large enough, otherwise the
98 definition of MB_CUR_MAX is not correct. All the other possible
99 errors also must not happen. */
100 assert (status == __GCONV_OK || status == __GCONV_EMPTY_INPUT
101 || status == __GCONV_ILLEGAL_INPUT
102 || status == __GCONV_INCOMPLETE_INPUT
103 || status == __GCONV_FULL_OUTPUT);
105 if (status == __GCONV_OK || status == __GCONV_EMPTY_INPUT
106 || status == __GCONV_FULL_OUTPUT)
107 result = data.__outbuf - (unsigned char *) s;
108 else
110 result = (size_t) -1;
111 __set_errno (EILSEQ);
114 return result;
116 weak_alias (__wcrtomb, wcrtomb)
117 libc_hidden_weak (wcrtomb)