source/lib/system.c

   1 /*
   2    Unix SMB/Netbios implementation.
   3    Version 1.9.
   4    Samba system utilities
   5    Copyright (C) Andrew Tridgell 1992-1997
   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 2 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, write to the Free Software
  19    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  20 */
  21
  22 #include "includes.h"
  23
  24 extern int DEBUGLEVEL;
  25
  26 /*
  27    The idea is that this file will eventually have wrappers around all
  28    important system calls in samba. The aims are:
  29
  30    - to enable easier porting by putting OS dependent stuff in here
  31
  32    - to allow for hooks into other "pseudo-filesystems"
  33
  34    - to allow easier integration of things like the japanese extensions
  35
  36    - to support the philosophy of Samba to expose the features of
  37      the OS within the SMB model. In general whatever file/printer/variable
  38      expansions/etc make sense to the OS should be acceptable to Samba.
  39 */
  40
  41
  42 /*******************************************************************
  43 this replaces the normal select() system call
  44 return if some data has arrived on one of the file descriptors
  45 return -1 means error
  46 ********************************************************************/
  47 #ifdef NO_SELECT
  48 static int pollfd(int fd)
  49 {
  50   int     r=0;
  51
  52 #ifdef HAS_RDCHK
  53   r = rdchk(fd);
  54 #elif defined(TCRDCHK)
  55   (void)ioctl(fd, TCRDCHK, &r);
  56 #else
  57   (void)ioctl(fd, FIONREAD, &r);
  58 #endif
  59
  60   return(r);
  61 }
  62
  63 int sys_select(fd_set *fds,struct timeval *tval)
  64 {
  65   fd_set fds2;
  66   int counter=0;
  67   int found=0;
  68
  69   FD_ZERO(&fds2);
  70
  71   while (1)
  72     {
  73       int i;
  74       for (i=0;i<255;i++) {
  75         if (FD_ISSET(i,fds) && pollfd(i)>0) {
  76           found++;
  77           FD_SET(i,&fds2);
  78         }
  79       }
  80
  81       if (found) {
  82         memcpy((void *)fds,(void *)&fds2,sizeof(fds2));
  83         return(found);
  84       }
  85
  86       if (tval && tval->tv_sec < counter) return(0);
  87       sleep(1);
  88       counter++;
  89     }
  90 }
  91
  92 #else
  93 int sys_select(fd_set *fds,struct timeval *tval)
  94 {
  95   struct timeval t2;
  96   int selrtn;
  97
  98   do {
  99     if (tval) memcpy((void *)&t2,(void *)tval,sizeof(t2));
 100     errno = 0;
 101     selrtn = select(255,SELECT_CAST fds,NULL,NULL,tval?&t2:NULL);
 102   } while (selrtn<0 && errno == EINTR);
 103
 104   return(selrtn);
 105 }
 106 #endif
 107
 108
 109 /*******************************************************************
 110 just a unlink wrapper
 111 ********************************************************************/
 112 int sys_unlink(char *fname)
 113 {
 114   return(unlink(dos_to_unix(fname,False)));
 115 }
 116
 117
 118 /*******************************************************************
 119 a simple open() wrapper
 120 ********************************************************************/
 121 int sys_open(char *fname,int flags,int mode)
 122 {
 123   return(open(dos_to_unix(fname,False),flags,mode));
 124 }
 125
 126
 127 /*******************************************************************
 128 a simple opendir() wrapper
 129 ********************************************************************/
 130 DIR *sys_opendir(char *dname)
 131 {
 132   return(opendir(dos_to_unix(dname,False)));
 133 }
 134
 135
 136 /*******************************************************************
 137 and a stat() wrapper
 138 ********************************************************************/
 139 int sys_stat(char *fname,struct stat *sbuf)
 140 {
 141   return(stat(dos_to_unix(fname,False),sbuf));
 142 }
 143
 144 /*******************************************************************
 145 The wait() calls vary between systems
 146 ********************************************************************/
 147 int sys_waitpid(pid_t pid,int *status,int options)
 148 {
 149 #ifdef USE_WAITPID
 150   return waitpid(pid,status,options);
 151 #else /* USE_WAITPID */
 152   return wait4(pid, status, options, NULL);
 153 #endif /* USE_WAITPID */
 154 }
 155
 156 /*******************************************************************
 157 don't forget lstat()
 158 ********************************************************************/
 159 int sys_lstat(char *fname,struct stat *sbuf)
 160 {
 161   return(lstat(dos_to_unix(fname,False),sbuf));
 162 }
 163
 164
 165 /*******************************************************************
 166 mkdir() gets a wrapper
 167 ********************************************************************/
 168 int sys_mkdir(char *dname,int mode)
 169 {
 170   return(mkdir(dos_to_unix(dname,False),mode));
 171 }
 172
 173
 174 /*******************************************************************
 175 do does rmdir()
 176 ********************************************************************/
 177 int sys_rmdir(char *dname)
 178 {
 179   return(rmdir(dos_to_unix(dname,False)));
 180 }
 181
 182
 183 /*******************************************************************
 184 I almost forgot chdir()
 185 ********************************************************************/
 186 int sys_chdir(char *dname)
 187 {
 188   return(chdir(dos_to_unix(dname,False)));
 189 }
 190
 191
 192 /*******************************************************************
 193 now for utime()
 194 ********************************************************************/
 195 int sys_utime(char *fname,struct utimbuf *times)
 196 {
 197   return(utime(dos_to_unix(fname,False),times));
 198 }
 199
 200 /*********************************************************
 201 for rename across filesystems Patch from Warren Birnbaum
 202 <warrenb@hpcvscdp.cv.hp.com>
 203 **********************************************************/
 204
 205 static int copy_reg(char *source, const char *dest)
 206 {
 207   struct stat source_stats;
 208   int ifd;
 209   int full_write();
 210   int safe_read();
 211   int ofd;
 212   char *buf;
 213   int len;                      /* Number of bytes read into `buf'. */
 214
 215   lstat (source, &source_stats);
 216   if (!S_ISREG (source_stats.st_mode))
 217     {
 218       return 1;
 219     }
 220
 221   if (unlink (dest) && errno != ENOENT)
 222     {
 223       return 1;
 224     }
 225
 226   if((ifd = open (source, O_RDONLY, 0)) < 0)
 227     {
 228       return 1;
 229     }
 230   if((ofd = open (dest, O_WRONLY | O_CREAT | O_TRUNC, 0600)) < 0 )
 231     {
 232       close (ifd);
 233       return 1;
 234     }
 235
 236   if((buf = malloc( COPYBUF_SIZE )) == NULL)
 237     {
 238       close (ifd);
 239       close (ofd);
 240       unlink (dest);
 241       return 1;
 242     }
 243
 244   while ((len = read(ifd, buf, COPYBUF_SIZE)) > 0)
 245     {
 246       if (write_data(ofd, buf, len) < 0)
 247         {
 248           close (ifd);
 249           close (ofd);
 250           unlink (dest);
 251           free(buf);
 252           return 1;
 253         }
 254     }
 255   free(buf);
 256   if (len < 0)
 257     {
 258       close (ifd);
 259       close (ofd);
 260       unlink (dest);
 261       return 1;
 262     }
 263
 264   if (close (ifd) < 0)
 265     {
 266       close (ofd);
 267       return 1;
 268     }
 269   if (close (ofd) < 0)
 270     {
 271       return 1;
 272     }
 273
 274   /* chown turns off set[ug]id bits for non-root,
 275      so do the chmod last.  */
 276
 277   /* Try to copy the old file's modtime and access time.  */
 278   {
 279     struct utimbuf tv;
 280
 281     tv.actime = source_stats.st_atime;
 282     tv.modtime = source_stats.st_mtime;
 283     if (utime (dest, &tv))
 284       {
 285         return 1;
 286       }
 287   }
 288
 289   /* Try to preserve ownership.  For non-root it might fail, but that's ok.
 290      But root probably wants to know, e.g. if NFS disallows it.  */
 291   if (chown (dest, source_stats.st_uid, source_stats.st_gid)
 292       && (errno != EPERM))
 293     {
 294       return 1;
 295     }
 296
 297   if (chmod (dest, source_stats.st_mode & 07777))
 298     {
 299       return 1;
 300     }
 301   unlink (source);
 302   return 0;
 303 }
 304
 305 /*******************************************************************
 306 for rename()
 307 ********************************************************************/
 308 int sys_rename(char *from, char *to)
 309 {
 310     int rcode;
 311     pstring zfrom, zto;
 312
 313     pstrcpy (zfrom, dos_to_unix (from, False));
 314     pstrcpy (zto, dos_to_unix (to, False));
 315     rcode = rename (zfrom, zto);
 316
 317     if (errno == EXDEV)
 318       {
 319         /* Rename across filesystems needed. */
 320         rcode = copy_reg (zfrom, zto);
 321       }
 322     return rcode;
 323 }
 324
 325 /*******************************************************************
 326 for chmod
 327 ********************************************************************/
 328 int sys_chmod(char *fname,int mode)
 329 {
 330   return(chmod(dos_to_unix(fname,False),mode));
 331 }
 332
 333 /*******************************************************************
 334 for getwd
 335 ********************************************************************/
 336 char *sys_getwd(char *s)
 337 {
 338   char *wd;
 339 #ifdef USE_GETCWD
 340   wd = (char *) getcwd (s, sizeof (pstring));
 341 #else
 342   wd = (char *) getwd (s);
 343 #endif
 344   if (wd)
 345     unix_to_dos (wd, True);
 346   return wd;
 347 }
 348
 349 /*******************************************************************
 350 chown isn't used much but OS/2 doesn't have it
 351 ********************************************************************/
 352 int sys_chown(char *fname,int uid,int gid)
 353 {
 354 #ifdef NO_CHOWN
 355   DEBUG(1,("Warning - chown(%s,%d,%d) not done\n",fname,uid,gid));
 356 #else
 357   return(chown(fname,uid,gid));
 358 #endif
 359 }
 360
 361 /*******************************************************************
 362 os/2 also doesn't have chroot
 363 ********************************************************************/
 364 int sys_chroot(char *dname)
 365 {
 366 #ifdef NO_CHROOT
 367   DEBUG(1,("Warning - chroot(%s) not done\n",dname));
 368 #else
 369   return(chroot(dname));
 370 #endif
 371 }
 372
 373 /**************************************************************************
 374 A wrapper for gethostbyname() that tries avoids looking up hostnames
 375 in the root domain, which can cause dial-on-demand links to come up for no
 376 apparent reason.
 377 ****************************************************************************/
 378 struct hostent *sys_gethostbyname(char *name)
 379 {
 380 #ifdef REDUCE_ROOT_DNS_LOOKUPS
 381   char query[256], hostname[256];
 382   char *domain;
 383
 384   /* Does this name have any dots in it? If so, make no change */
 385
 386   if (strchr(name, '.'))
 387     return(gethostbyname(name));
 388
 389   /* Get my hostname, which should have domain name
 390      attached. If not, just do the gethostname on the
 391      original string.
 392   */
 393
 394   gethostname(hostname, sizeof(hostname) - 1);
 395   hostname[sizeof(hostname) - 1] = 0;
 396   if ((domain = strchr(hostname, '.')) == NULL)
 397     return(gethostbyname(name));
 398
 399   /* Attach domain name to query and do modified query.
 400      If names too large, just do gethostname on the
 401      original string.
 402   */
 403
 404   if((strlen(name) + strlen(domain)) >= sizeof(query))
 405     return(gethostbyname(name));
 406
 407   sprintf(query, "%s%s", name, domain);
 408   return(gethostbyname(query));
 409 #else /* REDUCE_ROOT_DNS_LOOKUPS */
 410   return(gethostbyname(name));
 411 #endif /* REDUCE_ROOT_DNS_LOOKUPS */
 412 }
 413