usr/src/lib/libast/common/comp/open.c

   1 /***********************************************************************
   2 *                                                                      *
   3 *               This software is part of the ast package               *
   4 *          Copyright (c) 1985-2010 AT&T Intellectual Property          *
   5 *                      and is licensed under the                       *
   6 *                  Common Public License, Version 1.0                  *
   7 *                    by AT&T Intellectual Property                     *
   8 *                                                                      *
   9 *                A copy of the License is available at                 *
  10 *            http://www.opensource.org/licenses/cpl1.0.txt             *
  11 *         (with md5 checksum 059e8cd6165cb4c31e351f2b69388fd9)         *
  12 *                                                                      *
  13 *              Information and Software Systems Research               *
  14 *                            AT&T Research                             *
  15 *                           Florham Park NJ                            *
  16 *                                                                      *
  17 *                 Glenn Fowler <gsf@research.att.com>                  *
  18 *                  David Korn <dgk@research.att.com>                   *
  19 *                   Phong Vo <kpv@research.att.com>                    *
  20 *                                                                      *
  21 ***********************************************************************/
  22 #pragma prototyped
  23
  24 /*
  25  * -last 3 arg open
  26  */
  27
  28 #include <ast.h>
  29
  30 #if !defined(open) || !defined(_ast_O_LOCAL)
  31
  32 NoN(open)
  33
  34 #else
  35
  36 #undef  open
  37
  38 extern int      open(const char*, int, ...);
  39
  40 #include <ls.h>
  41 #include <error.h>
  42
  43 #ifdef O_NOCTTY
  44 #include <ast_tty.h>
  45 #endif
  46
  47 int
  48 _ast_open(const char* path, int op, ...)
  49 {
  50         int             fd;
  51         int             mode;
  52         int             save_errno;
  53         struct stat     st;
  54         va_list         ap;
  55
  56         save_errno = errno;
  57         va_start(ap, op);
  58         mode = (op & O_CREAT) ? va_arg(ap, int) : S_IRUSR|S_IWUSR|S_IRGRP|S_IWGRP|S_IROTH|S_IWOTH;
  59         va_end(ap);
  60         if (op & ~(_ast_O_LOCAL-1))
  61         {
  62                 if (!(op & O_CREAT))
  63                         op &= ~O_EXCL;
  64                 for (;;)
  65                 {
  66                         if (op & O_TRUNC)
  67                         {
  68                                 if ((op & O_EXCL) && !access(path, F_OK))
  69                                 {
  70                                         errno = EEXIST;
  71                                         return(-1);
  72                                 }
  73                                 if ((fd = creat(path, (op & O_EXCL) ? 0 : mode)) < 0)
  74                                         return(-1);
  75                                 if (op & O_EXCL)
  76                                 {
  77                                         if (fstat(fd, &st) || (st.st_mode & S_IPERM))
  78                                         {
  79                                                 errno = EEXIST;
  80                                                 close(fd);
  81                                                 return(-1);
  82                                         }
  83 #if _lib_fchmod
  84                                         if (mode && fchmod(fd, mode))
  85 #else
  86                                         if (mode && chmod(path, mode))
  87 #endif
  88                                                 errno = save_errno;
  89                                 }
  90                                 if ((op & O_ACCMODE) == O_RDWR)
  91                                 {
  92                                         close(fd);
  93                                         op &= ~(O_CREAT|O_TRUNC);
  94                                         continue;
  95                                 }
  96                         }
  97                         else if ((fd = open(path, op & (_ast_O_LOCAL-1), mode)) < 0)
  98                         {
  99                                 if (op & O_CREAT)
 100                                 {
 101                                         op |= O_TRUNC;
 102                                         continue;
 103                                 }
 104                                 return(-1);
 105                         }
 106                         else if ((op & O_APPEND) && lseek(fd, 0L, SEEK_END) == -1L)
 107                                 errno = save_errno;
 108 #if O_NOCTTY
 109                         if ((op & O_NOCTTY) && ioctl(fd, TIOCNOTTY, 0))
 110                                 errno = save_errno;
 111 #endif
 112                         break;
 113                 }
 114         }
 115         else fd = open(path, op, mode);
 116         return(fd);
 117 }
 118
 119 #endif