lib/util/system.c

   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 #undef malloc
  26
  27 /*
  28    The idea is that this file will eventually have wrappers around all
  29    important system calls in samba. The aims are:
  30
  31    - to enable easier porting by putting OS dependent stuff in here
  32
  33    - to allow for hooks into other "pseudo-filesystems"
  34
  35    - to allow easier integration of things like the japanese extensions
  36
  37    - to support the philosophy of Samba to expose the features of
  38      the OS within the SMB model. In general whatever file/printer/variable
  39      expansions/etc make sense to the OS should be acceptable to Samba.
  40 */
  41
  42 /*******************************************************************
  43  A wrapper for memalign
  44 ********************************************************************/
  45
  46 void *sys_memalign( size_t align, size_t size )
  47 {
  48 #if defined(HAVE_POSIX_MEMALIGN)
  49         void *p = NULL;
  50         int ret = posix_memalign( &p, align, size );
  51         if ( ret == 0 )
  52                 return p;
  53
  54         return NULL;
  55 #elif defined(HAVE_MEMALIGN)
  56         return memalign( align, size );
  57 #else
  58         /* On *BSD systems memaligns doesn't exist, but memory will
  59          * be aligned on allocations of > pagesize. */
  60 #if defined(SYSCONF_SC_PAGESIZE)
  61         size_t pagesize = (size_t)sysconf(_SC_PAGESIZE);
  62 #elif defined(HAVE_GETPAGESIZE)
  63         size_t pagesize = (size_t)getpagesize();
  64 #else
  65         size_t pagesize = (size_t)-1;
  66 #endif
  67         if (pagesize == (size_t)-1) {
  68                 DEBUG(0,("memalign functionalaity not available on this platform!\n"));
  69                 return NULL;
  70         }
  71         if (size < pagesize) {
  72                 size = pagesize;
  73         }
  74         return malloc(size);
  75 #endif
  76 }
  77
  78 /**************************************************************************
  79  Wrapper for fork. Ensures we clear our pid cache.
  80 ****************************************************************************/
  81
  82 static pid_t mypid = (pid_t)-1;
  83
  84 _PUBLIC_ pid_t sys_fork(void)
  85 {
  86         pid_t forkret = fork();
  87
  88         if (forkret == (pid_t)0) {
  89                 /* Child - reset mypid so sys_getpid does a system call. */
  90                 mypid = (pid_t) -1;
  91         }
  92
  93         return forkret;
  94 }
  95
  96 /**************************************************************************
  97  Wrapper for getpid. Ensures we only do a system call *once*.
  98 ****************************************************************************/
  99
 100 _PUBLIC_ pid_t sys_getpid(void)
 101 {
 102         if (mypid == (pid_t)-1)
 103                 mypid = getpid();
 104
 105         return mypid;
 106 }
 107
 108
 109 _PUBLIC_ int sys_getpeereid( int s, uid_t *uid)
 110 {
 111 #if defined(HAVE_PEERCRED)
 112         struct ucred cred;
 113         socklen_t cred_len = sizeof(struct ucred);
 114         int ret;
 115
 116         ret = getsockopt(s, SOL_SOCKET, SO_PEERCRED, (void *)&cred, &cred_len);
 117         if (ret != 0) {
 118                 return -1;
 119         }
 120
 121         if (cred_len != sizeof(struct ucred)) {
 122                 errno = EINVAL;
 123                 return -1;
 124         }
 125
 126         *uid = cred.uid;
 127         return 0;
 128 #else
 129 #if defined(HAVE_GETPEEREID)
 130         gid_t gid;
 131         return getpeereid(s, uid, &gid);
 132 #endif
 133         errno = ENOSYS;
 134         return -1;
 135 #endif
 136 }
 137
 138 _PUBLIC_ int sys_getnameinfo(const struct sockaddr *psa,
 139                              int salen,
 140                              char *host,
 141                              size_t hostlen,
 142                              char *service,
 143                              size_t servlen,
 144                              int flags)
 145 {
 146         /*
 147          * For Solaris we must make sure salen is the
 148          * correct length for the incoming sa_family.
 149          */
 150
 151         if (salen == sizeof(struct sockaddr_storage)) {
 152                 salen = sizeof(struct sockaddr_in);
 153 #if defined(HAVE_IPV6)
 154                 if (psa->sa_family == AF_INET6) {
 155                         salen = sizeof(struct sockaddr_in6);
 156                 }
 157 #endif
 158         }
 159         return getnameinfo(psa, salen, host, hostlen, service, servlen, flags);
 160 }
 161
 162 _PUBLIC_ int sys_connect(int fd, const struct sockaddr * addr)
 163 {
 164         socklen_t salen = (socklen_t)-1;
 165
 166         if (addr->sa_family == AF_INET) {
 167             salen = sizeof(struct sockaddr_in);
 168         } else if (addr->sa_family == AF_UNIX) {
 169             salen = sizeof(struct sockaddr_un);
 170         }
 171 #if defined(HAVE_IPV6)
 172         else if (addr->sa_family == AF_INET6) {
 173             salen = sizeof(struct sockaddr_in6);
 174         }
 175 #endif
 176
 177         return connect(fd, addr, salen);
 178 }
 179