libexec/cron/compat.c

   1 /* Copyright 1988,1990,1993 by Paul Vixie
   2  * All rights reserved
   3  *
   4  * Distribute freely, except: don't remove my name from the source or
   5  * documentation (don't take credit for my work), mark your changes (don't
   6  * get me blamed for your possible bugs), don't alter or remove this
   7  * notice.  May be sold if buildable source is provided to buyer.  No
   8  * warrantee of any kind, express or implied, is included with this
   9  * software; use at your own risk, responsibility for damages (if any) to
  10  * anyone resulting from the use of this software rests entirely with the
  11  * user.
  12  *
  13  * Send bug reports, bug fixes, enhancements, requests, flames, etc., and
  14  * I'll try to keep a version up to date.  I can be reached as follows:
  15  * Paul Vixie          <paul@vix.com>          uunet!decwrl!vixie!paul
  16  */
  17
  18 #if !defined(lint) && !defined(LINT)
  19 static char rcsid[] = "$Id: compat.c,v 1.1 1994/01/05 20:40:12 jtc Exp $";
  20 #endif
  21
  22 /* vix 30dec93 [broke this out of misc.c - see RCS log for history]
  23  * vix 15jan87 [added TIOCNOTTY, thanks csg@pyramid]
  24  */
  25
  26
  27 #include "cron.h"
  28 #include "externs.h"
  29 #ifdef NEED_GETDTABLESIZE
  30 # include <limits.h>
  31 #endif
  32 #if defined(NEED_SETSID) && defined(BSD)
  33 # include <sys/ioctl.h>
  34 #endif
  35 #include <errno.h>
  36
  37
  38 /* the code does not depend on any of vfork's
  39  * side-effects; it just uses it as a quick
  40  * fork-and-exec.
  41  */
  42 #ifdef NEED_VFORK
  43 PID_T
  44 vfork() {
  45         return (fork());
  46 }
  47 #endif
  48
  49
  50 #ifdef NEED_STRDUP
  51 char *
  52 strdup(str)
  53         char    *str;
  54 {
  55         char    *temp;
  56
  57         temp = malloc(strlen(str) + 1);
  58         (void) strcpy(temp, str);
  59         return temp;
  60 }
  61 #endif
  62
  63
  64 #ifdef NEED_STRERROR
  65 char *
  66 strerror(error)
  67         int error;
  68 {
  69         extern char *sys_errlist[];
  70         extern int sys_nerr;
  71         static char buf[32];
  72
  73         if ((error <= sys_nerr) && (error > 0)) {
  74                 return sys_errlist[error];
  75         }
  76
  77         sprintf(buf, "Unknown error: %d", error);
  78         return buf;
  79 }
  80 #endif
  81
  82
  83 #ifdef NEED_STRCASECMP
  84 int
  85 strcasecmp(left, right)
  86         char    *left;
  87         char    *right;
  88 {
  89         while (*left && (MkLower(*left) == MkLower(*right))) {
  90                 left++;
  91                 right++;
  92         }
  93         return MkLower(*left) - MkLower(*right);
  94 }
  95 #endif
  96
  97
  98 #ifdef NEED_SETSID
  99 int
 100 setsid()
 101 {
 102         int     newpgrp;
 103 # if defined(BSD)
 104         int     fd;
 105 #  if defined(POSIX)
 106         newpgrp = setpgid((pid_t)0, getpid());
 107 #  else
 108         newpgrp = setpgrp(0, getpid());
 109 #  endif
 110         if ((fd = open("/dev/tty", 2)) >= 0)
 111         {
 112                 (void) ioctl(fd, TIOCNOTTY, (char*)0);
 113                 (void) close(fd);
 114         }
 115 # else /*BSD*/
 116         newpgrp = setpgrp();
 117
 118         (void) close(STDIN);    (void) open("/dev/null", 0);
 119         (void) close(STDOUT);   (void) open("/dev/null", 1);
 120         (void) close(STDERR);   (void) open("/dev/null", 2);
 121 # endif /*BSD*/
 122         return newpgrp;
 123 }
 124 #endif /*NEED_SETSID*/
 125
 126
 127 #ifdef NEED_GETDTABLESIZE
 128 int
 129 getdtablesize() {
 130 #ifdef _SC_OPEN_MAX
 131         return sysconf(_SC_OPEN_MAX);
 132 #else
 133         return _POSIX_OPEN_MAX;
 134 #endif
 135 }
 136 #endif
 137
 138
 139 #ifdef NEED_FLOCK
 140 /* The following flock() emulation snarfed intact *) from the HP-UX
 141  * "BSD to HP-UX porting tricks" maintained by
 142  * system@alchemy.chem.utoronto.ca (System Admin (Mike Peterson))
 143  * from the version "last updated: 11-Jan-1993"
 144  * Snarfage done by Jarkko Hietaniemi <Jarkko.Hietaniemi@hut.fi>
 145  * *) well, almost, had to K&R the function entry, HPUX "cc"
 146  * does not grok ANSI function prototypes */
 147
 148 /*
 149  * flock (fd, operation)
 150  *
 151  * This routine performs some file locking like the BSD 'flock'
 152  * on the object described by the int file descriptor 'fd',
 153  * which must already be open.
 154  *
 155  * The operations that are available are:
 156  *
 157  * LOCK_SH  -  get a shared lock.
 158  * LOCK_EX  -  get an exclusive lock.
 159  * LOCK_NB  -  don't block (must be ORed with LOCK_SH or LOCK_EX).
 160  * LOCK_UN  -  release a lock.
 161  *
 162  * Return value: 0 if lock successful, -1 if failed.
 163  *
 164  * Note that whether the locks are enforced or advisory is
 165  * controlled by the presence or absence of the SETGID bit on
 166  * the executable.
 167  *
 168  * Note that there is no difference between shared and exclusive
 169  * locks, since the 'lockf' system call in SYSV doesn't make any
 170  * distinction.
 171  *
 172  * The file "<sys/file.h>" should be modified to contain the definitions
 173  * of the available operations, which must be added manually (see below
 174  * for the values).
 175  */
 176
 177 /* this code has been reformatted by vixie */
 178
 179 int
 180 flock(fd, operation)
 181         int fd;
 182         int operation;
 183 {
 184         int i;
 185
 186         switch (operation) {
 187         case LOCK_SH:           /* get a shared lock */
 188         case LOCK_EX:           /* get an exclusive lock */
 189                 i = lockf (fd, F_LOCK, 0);
 190                 break;
 191
 192         case LOCK_SH|LOCK_NB:   /* get a non-blocking shared lock */
 193         case LOCK_EX|LOCK_NB:   /* get a non-blocking exclusive lock */
 194                 i = lockf (fd, F_TLOCK, 0);
 195                 if (i == -1)
 196                         if ((errno == EAGAIN) || (errno == EACCES))
 197                                 errno = EWOULDBLOCK;
 198                 break;
 199
 200         case LOCK_UN:           /* unlock */
 201                 i = lockf (fd, F_ULOCK, 0);
 202                 break;
 203
 204         default:                /* can't decipher operation */
 205                 i = -1;
 206                 errno = EINVAL;
 207                 break;
 208         }
 209
 210         return (i);
 211 }
 212 #endif /*NEED_FLOCK*/
 213
 214
 215 #ifdef NEED_SETENV
 216 int
 217 setenv(name, value, overwrite)
 218         char *name, *value;
 219         int overwrite;
 220 {
 221         char *tmp;
 222
 223         if (overwrite && getenv(name))
 224                 return -1;
 225
 226         if (!(tmp = malloc(strlen(name) + strlen(value) + 2))) {
 227                 errno = ENOMEM;
 228                 return -1;
 229         }
 230
 231         sprintf("%s=%s", name, value);
 232         return putenv(tmp);     /* intentionally orphan 'tmp' storage */
 233 }
 234 #endif