xref: /xnu-8020.140.41/libsyscall/mach/fprintf_stderr.c (revision 27b03b360a988dfd3dfdf34262bb0042026747cc)
1*27b03b36SApple OSS Distributions /*
2*27b03b36SApple OSS Distributions  * Copyright (c) 2003-2010 Apple Inc. All rights reserved.
3*27b03b36SApple OSS Distributions  *
4*27b03b36SApple OSS Distributions  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
5*27b03b36SApple OSS Distributions  *
6*27b03b36SApple OSS Distributions  * This file contains Original Code and/or Modifications of Original Code
7*27b03b36SApple OSS Distributions  * as defined in and that are subject to the Apple Public Source License
8*27b03b36SApple OSS Distributions  * Version 2.0 (the 'License'). You may not use this file except in
9*27b03b36SApple OSS Distributions  * compliance with the License. The rights granted to you under the License
10*27b03b36SApple OSS Distributions  * may not be used to create, or enable the creation or redistribution of,
11*27b03b36SApple OSS Distributions  * unlawful or unlicensed copies of an Apple operating system, or to
12*27b03b36SApple OSS Distributions  * circumvent, violate, or enable the circumvention or violation of, any
13*27b03b36SApple OSS Distributions  * terms of an Apple operating system software license agreement.
14*27b03b36SApple OSS Distributions  *
15*27b03b36SApple OSS Distributions  * Please obtain a copy of the License at
16*27b03b36SApple OSS Distributions  * http://www.opensource.apple.com/apsl/ and read it before using this file.
17*27b03b36SApple OSS Distributions  *
18*27b03b36SApple OSS Distributions  * The Original Code and all software distributed under the License are
19*27b03b36SApple OSS Distributions  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
20*27b03b36SApple OSS Distributions  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
21*27b03b36SApple OSS Distributions  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
22*27b03b36SApple OSS Distributions  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
23*27b03b36SApple OSS Distributions  * Please see the License for the specific language governing rights and
24*27b03b36SApple OSS Distributions  * limitations under the License.
25*27b03b36SApple OSS Distributions  *
26*27b03b36SApple OSS Distributions  * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
27*27b03b36SApple OSS Distributions  */
28*27b03b36SApple OSS Distributions /*
29*27b03b36SApple OSS Distributions  * @OSF_FREE_COPYRIGHT@
30*27b03b36SApple OSS Distributions  *
31*27b03b36SApple OSS Distributions  */
32*27b03b36SApple OSS Distributions 
33*27b03b36SApple OSS Distributions #include <mach/mach.h>
34*27b03b36SApple OSS Distributions #include <mach/mach_init.h>
35*27b03b36SApple OSS Distributions #include <stdarg.h>
36*27b03b36SApple OSS Distributions #include "string.h"
37*27b03b36SApple OSS Distributions 
38*27b03b36SApple OSS Distributions int (*vprintf_stderr_func)(const char *format, va_list ap) __printflike(1, 0);
39*27b03b36SApple OSS Distributions 
40*27b03b36SApple OSS Distributions #define __STDERR_FILENO 2
41*27b03b36SApple OSS Distributions int write(int fd, const char* cbuf, int nbyte);
42*27b03b36SApple OSS Distributions 
43*27b03b36SApple OSS Distributions /* This function allows the writing of a mach error message to an
44*27b03b36SApple OSS Distributions  * application-controllable output method, the default being to
45*27b03b36SApple OSS Distributions  * use printf if no other method is specified by the application.
46*27b03b36SApple OSS Distributions  *
47*27b03b36SApple OSS Distributions  * To override, set the global function pointer vprintf_stderr to
48*27b03b36SApple OSS Distributions  * a function which takes the same parameters as vprintf.
49*27b03b36SApple OSS Distributions  */
50*27b03b36SApple OSS Distributions 
51*27b03b36SApple OSS Distributions __printflike(1, 2)
52*27b03b36SApple OSS Distributions __private_extern__ int
fprintf_stderr(const char * format,...)53*27b03b36SApple OSS Distributions fprintf_stderr(const char *format, ...)
54*27b03b36SApple OSS Distributions {
55*27b03b36SApple OSS Distributions 	va_list args;
56*27b03b36SApple OSS Distributions 	int retval;
57*27b03b36SApple OSS Distributions 
58*27b03b36SApple OSS Distributions 	va_start(args, format);
59*27b03b36SApple OSS Distributions 	if (vprintf_stderr_func == NULL) {
60*27b03b36SApple OSS Distributions 		char buffer[1024];
61*27b03b36SApple OSS Distributions 		retval = _mach_vsnprintf(buffer, sizeof(buffer), format, args);
62*27b03b36SApple OSS Distributions 		write(__STDERR_FILENO, buffer, retval);
63*27b03b36SApple OSS Distributions 	} else {
64*27b03b36SApple OSS Distributions 		retval = (*vprintf_stderr_func)(format, args);
65*27b03b36SApple OSS Distributions 	}
66*27b03b36SApple OSS Distributions 	va_end(args);
67*27b03b36SApple OSS Distributions 
68*27b03b36SApple OSS Distributions 	return retval;
69*27b03b36SApple OSS Distributions }
70