xref: /illumos-gate/usr/src/lib/libc/port/stdio/vscanf.c (revision 004388eb)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 
22 /*
23  * Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 /*	Copyright (c) 1988 AT&T	*/
28 /*	  All Rights Reserved  	*/
29 
30 #pragma ident	"%Z%%M%	%I%	%E% SMI"
31 
32 
33 #ifndef _C89_INTMAX32
34 #pragma weak vscanf = _vscanf
35 #pragma weak vfscanf = _vfscanf
36 #pragma weak vsscanf = _vsscanf
37 #endif
38 
39 #include "synonyms.h"
40 #include "file64.h"
41 #include "mtlib.h"
42 #include <stdio.h>
43 #include <stdarg.h>
44 #include <string.h>
45 #include <thread.h>
46 #include <synch.h>
47 #include "libc.h"
48 #include "stdiom.h"
49 #include "mse.h"
50 #include <stdio_ext.h>
51 
52 
53 /*
54  * 32-bit shadow functions _vscanf_c89(), _vfscanf_c89(), _vsscanf_c89()
55  * are included here.
56  * When using the c89 compiler to build 32-bit applications, the size
57  * of intmax_t is 32-bits, otherwise the size of intmax_t is 64-bits.
58  * The shadow function uses 32-bit size of intmax_t for %j conversion.
59  * The #pragma redefine_extname in <stdio.h> selects the proper routine
60  * at compile time for the user application.
61  * NOTE: the shadow function only exists in the 32-bit library.
62  */
63 
64 int
65 #ifdef _C89_INTMAX32	/* _C89_INTMAX32 version in 32-bit libc only */
66 _vscanf_c89(const char *fmt, va_list ap)
67 #else
68 vscanf(const char *fmt, va_list ap)
69 #endif
70 {
71 	rmutex_t	*lk;
72 	int	ret;
73 
74 	FLOCKFILE(lk, stdin);
75 
76 	_SET_ORIENTATION_BYTE(stdin);
77 
78 #ifdef _C89_INTMAX32
79 	ret = __doscan_u(stdin, fmt, ap, _F_INTMAX32);
80 #else
81 	ret = __doscan_u(stdin, fmt, ap, 0);
82 #endif
83 
84 	FUNLOCKFILE(lk);
85 	return (ret);
86 }
87 
88 int
89 #ifdef _C89_INTMAX32	/* _C89_INTMAX32 version in 32-bit libc only */
90 _vfscanf_c89(FILE *iop, const char *fmt, va_list ap)
91 #else
92 vfscanf(FILE *iop, const char *fmt, va_list ap)
93 #endif
94 {
95 	rmutex_t	*lk;
96 	int	ret;
97 
98 	FLOCKFILE(lk, iop);
99 
100 	_SET_ORIENTATION_BYTE(iop);
101 
102 #ifdef _C89_INTMAX32
103 	ret = __doscan_u(iop, fmt, ap, _F_INTMAX32);
104 #else
105 	ret = __doscan_u(iop, fmt, ap, 0);
106 #endif
107 	FUNLOCKFILE(lk);
108 	return (ret);
109 }
110 
111 int
112 #ifdef _C89_INTMAX32	/* _C89_INTMAX32 version in 32-bit libc only */
113 _vsscanf_c89(const char *str, const char *fmt, va_list ap)
114 #else
115 vsscanf(const char *str, const char *fmt, va_list ap)
116 #endif
117 {
118 	FILE strbuf;
119 
120 	/*
121 	 * The dummy FILE * created for sscanf has the _IOWRT
122 	 * flag set to distinguish it from scanf and fscanf
123 	 * invocations.
124 	 */
125 	strbuf._flag = _IOREAD | _IOWRT;
126 	strbuf._ptr = strbuf._base = (unsigned char *)str;
127 	strbuf._cnt = strlen(str);
128 	SET_FILE(&strbuf, _NFILE);
129 
130 	/*
131 	 * Mark the stream so that routines called by __doscan_u()
132 	 * do not do any locking. In particular this avoids a NULL
133 	 * lock pointer being used by getc() causing a core dump.
134 	 * See bugid -  1210179 program SEGV's in sscanf if linked with
135 	 * the libthread.
136 	 * This also makes sscanf() quicker since it does not need
137 	 * to do any locking.
138 	 */
139 	if (__fsetlocking(&strbuf, FSETLOCKING_BYCALLER) == -1) {
140 		return (-1);	/* this should never happen */
141 	}
142 
143 	/* as this stream is local to this function, no locking is be done */
144 #ifdef _C89_INTMAX32
145 	return (__doscan_u(&strbuf, fmt, ap, _F_INTMAX32));
146 #else
147 	return (__doscan_u(&strbuf, fmt, ap, 0));
148 #endif
149 }
150