1/*
2   Unix SMB/CIFS implementation.
3   Samba system utilities
4   Copyright (C) Andrew Tridgell 1992-1998
5   Copyright (C) Jeremy Allison 1998-2002
6
7   This program is free software; you can redistribute it and/or modify
8   it under the terms of the GNU General Public License as published by
9   the Free Software Foundation; either version 3 of the License, or
10   (at your option) any later version.
11
12   This program is distributed in the hope that it will be useful,
13   but WITHOUT ANY WARRANTY; without even the implied warranty of
14   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15   GNU General Public License for more details.
16
17   You should have received a copy of the GNU General Public License
18   along with this program.  If not, see <http://www.gnu.org/licenses/>.
19*/
20
21#include "includes.h"
22#include "system/network.h"
23#include "system/filesys.h"
24
25/*
26   The idea is that this file will eventually have wrappers around all
27   important system calls in samba. The aims are:
28
29   - to enable easier porting by putting OS dependent stuff in here
30
31   - to allow for hooks into other "pseudo-filesystems"
32
33   - to allow easier integration of things like the japanese extensions
34
35   - to support the philosophy of Samba to expose the features of
36     the OS within the SMB model. In general whatever file/printer/variable
37     expansions/etc make sense to the OS should be acceptable to Samba.
38*/
39
40/**************************************************************************
41A wrapper for gethostbyname() that tries avoids looking up hostnames
42in the root domain, which can cause dial-on-demand links to come up for no
43apparent reason.
44****************************************************************************/
45
46_PUBLIC_ struct hostent *sys_gethostbyname(const char *name)
47{
48#ifdef REDUCE_ROOT_DNS_LOOKUPS
49	char query[256], hostname[256];
50	char *domain;
51
52	/* Does this name have any dots in it? If so, make no change */
53
54	if (strchr(name, '.'))
55		return(gethostbyname(name));
56
57	/* Get my hostname, which should have domain name
58		attached. If not, just do the gethostname on the
59		original string.
60	*/
61
62	gethostname(hostname, sizeof(hostname) - 1);
63	hostname[sizeof(hostname) - 1] = 0;
64	if ((domain = strchr(hostname, '.')) == NULL)
65		return(gethostbyname(name));
66
67	/* Attach domain name to query and do modified query.
68		If names too large, just do gethostname on the
69		original string.
70	*/
71
72	if((strlen(name) + strlen(domain)) >= sizeof(query))
73		return(gethostbyname(name));
74
75	slprintf(query, sizeof(query)-1, "%s%s", name, domain);
76	return(gethostbyname(query));
77#else /* REDUCE_ROOT_DNS_LOOKUPS */
78	return(gethostbyname(name));
79#endif /* REDUCE_ROOT_DNS_LOOKUPS */
80}
81
82_PUBLIC_ struct in_addr sys_inet_makeaddr(int net, int host)
83{
84	struct in_addr in;
85	struct in_addr in2;
86	in = inet_makeaddr(net, host);
87	in2.s_addr = in.s_addr;
88	return in2;
89}
90
91/**************************************************************************
92 Wrapper for fork. Ensures we clear our pid cache.
93****************************************************************************/
94
95static pid_t mypid = (pid_t)-1;
96
97_PUBLIC_ pid_t sys_fork(void)
98{
99	pid_t forkret = fork();
100
101	if (forkret == (pid_t)0) {
102		/* Child - reset mypid so sys_getpid does a system call. */
103		mypid = (pid_t) -1;
104	}
105
106	return forkret;
107}
108
109/**************************************************************************
110 Wrapper for getpid. Ensures we only do a system call *once*.
111****************************************************************************/
112
113_PUBLIC_ pid_t sys_getpid(void)
114{
115	if (mypid == (pid_t)-1)
116		mypid = getpid();
117
118	return mypid;
119}
120