xref: /illumos-gate/usr/src/lib/libc/port/stdio/vscanf.c (revision 1f5207b7604fb44407eb4342aff613f7c4508508)
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 2008 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 #ifndef _C89_INTMAX32
33 #pragma weak _vscanf = vscanf
34 #pragma weak _vfscanf = vfscanf
35 #pragma weak _vsscanf = vsscanf
36 #endif
37 
38 #include "lint.h"
39 #include "file64.h"
40 #include "mtlib.h"
41 #include <stdio.h>
42 #include <stdarg.h>
43 #include <string.h>
44 #include <thread.h>
45 #include <synch.h>
46 #include "libc.h"
47 #include "stdiom.h"
48 #include "mse.h"
49 #include <stdio_ext.h>
50 
51 
52 /*
53  * 32-bit shadow functions _vscanf_c89(), _vfscanf_c89(), _vsscanf_c89()
54  * are included here.
55  * When using the c89 compiler to build 32-bit applications, the size
56  * of intmax_t is 32-bits, otherwise the size of intmax_t is 64-bits.
57  * The shadow function uses 32-bit size of intmax_t for %j conversion.
58  * The #pragma redefine_extname in <stdio.h> selects the proper routine
59  * at compile time for the user application.
60  * NOTE: the shadow function only exists in the 32-bit library.
61  */
62 
63 int
64 #ifdef _C89_INTMAX32	/* _C89_INTMAX32 version in 32-bit libc only */
65 _vscanf_c89(const char *fmt, va_list ap)
66 #else
67 vscanf(const char *fmt, va_list ap)
68 #endif
69 {
70 	rmutex_t	*lk;
71 	int	ret;
72 
73 	FLOCKFILE(lk, stdin);
74 
75 	_SET_ORIENTATION_BYTE(stdin);
76 
77 #ifdef _C89_INTMAX32
78 	ret = __doscan_u(stdin, fmt, ap, _F_INTMAX32);
79 #else
80 	ret = __doscan_u(stdin, fmt, ap, 0);
81 #endif
82 
83 	FUNLOCKFILE(lk);
84 	return (ret);
85 }
86 
87 int
88 #ifdef _C89_INTMAX32	/* _C89_INTMAX32 version in 32-bit libc only */
89 _vfscanf_c89(FILE *iop, const char *fmt, va_list ap)
90 #else
91 vfscanf(FILE *iop, const char *fmt, va_list ap)
92 #endif
93 {
94 	rmutex_t	*lk;
95 	int	ret;
96 
97 	FLOCKFILE(lk, iop);
98 
99 	_SET_ORIENTATION_BYTE(iop);
100 
101 #ifdef _C89_INTMAX32
102 	ret = __doscan_u(iop, fmt, ap, _F_INTMAX32);
103 #else
104 	ret = __doscan_u(iop, fmt, ap, 0);
105 #endif
106 	FUNLOCKFILE(lk);
107 	return (ret);
108 }
109 
110 int
111 #ifdef _C89_INTMAX32	/* _C89_INTMAX32 version in 32-bit libc only */
112 _vsscanf_c89(const char *str, const char *fmt, va_list ap)
113 #else
114 vsscanf(const char *str, const char *fmt, va_list ap)
115 #endif
116 {
117 	FILE strbuf;
118 
119 	/*
120 	 * The dummy FILE * created for sscanf has the _IOWRT
121 	 * flag set to distinguish it from scanf and fscanf
122 	 * invocations.
123 	 */
124 	strbuf._flag = _IOREAD | _IOWRT;
125 	strbuf._ptr = strbuf._base = (unsigned char *)str;
126 	strbuf._cnt = strlen(str);
127 	SET_FILE(&strbuf, _NFILE);
128 
129 	/*
130 	 * Mark the stream so that routines called by __doscan_u()
131 	 * do not do any locking. In particular this avoids a NULL
132 	 * lock pointer being used by getc() causing a core dump.
133 	 * See bugid -  1210179 program SEGV's in sscanf if linked with
134 	 * the libthread.
135 	 * This also makes sscanf() quicker since it does not need
136 	 * to do any locking.
137 	 */
138 	if (__fsetlocking(&strbuf, FSETLOCKING_BYCALLER) == -1) {
139 		return (-1);	/* this should never happen */
140 	}
141 
142 	/* as this stream is local to this function, no locking is be done */
143 #ifdef _C89_INTMAX32
144 	return (__doscan_u(&strbuf, fmt, ap, _F_INTMAX32));
145 #else
146 	return (__doscan_u(&strbuf, fmt, ap, 0));
147 #endif
148 }
149