1 /*
2  * Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC")
3  * Copyright (c) 2001 by Internet Software Consortium.
4  *
5  * Permission to use, copy, modify, and distribute this software for any
6  * purpose with or without fee is hereby granted, provided that the above
7  * copyright notice and this permission notice appear in all copies.
8  *
9  * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES
10  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
11  * MERCHANTABILITY AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR
12  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
13  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
14  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
15  * OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
16  */
17 
18 #include <port_before.h>
19 #include <netdb.h>
20 #include <port_after.h>
21 
22 #ifdef DO_PTHREADS
23 #include <pthread.h>
24 #include <stdlib.h>
25 #endif
26 
27 static const char *gai_errlist[] = {
28 	"no error",
29 	"address family not supported for name",/*%< EAI_ADDRFAMILY */
30 	"temporary failure",			/*%< EAI_AGAIN */
31 	"invalid flags",			/*%< EAI_BADFLAGS */
32 	"permanent failure",			/*%< EAI_FAIL */
33 	"address family not supported",		/*%< EAI_FAMILY */
34 	"memory failure",			/*%< EAI_MEMORY */
35 	"no address",				/*%< EAI_NODATA */
36 	"unknown name or service",		/*%< EAI_NONAME */
37 	"service not supported for socktype",	/*%< EAI_SERVICE */
38 	"socktype not supported",		/*%< EAI_SOCKTYPE */
39 	"system failure",			/*%< EAI_SYSTEM */
40 	"bad hints",				/*%< EAI_BADHINTS */
41 	"bad protocol",				/*%< EAI_PROTOCOL */
42 	"unknown error"				/*%< Must be last. */
43 };
44 
45 static const int gai_nerr = (sizeof(gai_errlist)/sizeof(*gai_errlist));
46 
47 #define EAI_BUFSIZE 128
48 
49 const char *
50 gai_strerror(int ecode) {
51 #ifndef DO_PTHREADS
52 	static char buf[EAI_BUFSIZE];
53 #else	/* DO_PTHREADS */
54 #ifndef LIBBIND_MUTEX_INITIALIZER
55 #define LIBBIND_MUTEX_INITIALIZER PTHREAD_MUTEX_INITIALIZER
56 #endif
57 	static pthread_mutex_t lock = LIBBIND_MUTEX_INITIALIZER;
58 	static pthread_key_t key;
59 	static int once = 0;
60 	char *buf;
61 #endif
62 
63 	if (ecode >= 0 && ecode < (gai_nerr - 1))
64 		return (gai_errlist[ecode]);
65 
66 #ifdef DO_PTHREADS
67         if (!once) {
68                 if (pthread_mutex_lock(&lock) != 0)
69 			goto unknown;
70                 if (!once) {
71                         if (pthread_key_create(&key, free) != 0) {
72 				(void)pthread_mutex_unlock(&lock);
73 				goto unknown;
74 			}
75 			once = 1;
76 		}
77                 if (pthread_mutex_unlock(&lock) != 0)
78 			goto unknown;
79         }
80 
81 	buf = pthread_getspecific(key);
82         if (buf == NULL) {
83 		buf = malloc(EAI_BUFSIZE);
84                 if (buf == NULL)
85                         goto unknown;
86                 if (pthread_setspecific(key, buf) != 0) {
87 			free(buf);
88 			goto unknown;
89 		}
90         }
91 #endif
92 	/*
93 	 * XXX This really should be snprintf(buf, EAI_BUFSIZE, ...).
94 	 * It is safe until message catalogs are used.
95 	 */
96 	sprintf(buf, "%s: %d", gai_errlist[gai_nerr - 1], ecode);
97 	return (buf);
98 
99 #ifdef DO_PTHREADS
100  unknown:
101 	return ("unknown error");
102 #endif
103 }
104 
105 /*! \file */
106