libjava/posix.cc

   1 // posix.cc -- Helper functions for POSIX-flavored OSs.
   2
   3 /* Copyright (C) 2000, 2001, 2002  Free Software Foundation
   4
   5    This file is part of libgcj.
   6
   7 This software is copyrighted work licensed under the terms of the
   8 Libgcj License.  Please consult the file "LIBGCJ_LICENSE" for
   9 details.  */
  10
  11 #include <config.h>
  12
  13 #include "posix.h"
  14
  15 #include <stdlib.h>
  16 #include <errno.h>
  17 #include <signal.h>
  18 #include <stdio.h>
  19
  20 #include <jvm.h>
  21 #include <java/lang/Thread.h>
  22 #include <java/io/InterruptedIOException.h>
  23 #include <java/util/Properties.h>
  24
  25 #if defined (ECOS)
  26 extern "C" unsigned long long _clock (void);
  27 #endif
  28
  29 #if defined(HAVE_PROC_SELF_EXE)
  30 static char exec_name[20];
  31   // initialized in _Jv_platform_initialize()
  32 #endif
  33
  34 const char *_Jv_ThisExecutable (void)
  35 {
  36 #if defined(DISABLE_MAIN_ARGS)
  37   return "[Embedded App]";
  38 #elif defined(HAVE_PROC_SELF_EXE)
  39   return exec_name;
  40     // initialized in _Jv_platform_initialize()
  41 #else
  42   return _Jv_GetSafeArg (0);
  43 #endif
  44 }
  45
  46 // gettimeofday implementation.
  47 jlong
  48 _Jv_platform_gettimeofday ()
  49 {
  50 #if defined (HAVE_GETTIMEOFDAY)
  51   timeval tv;
  52   gettimeofday (&tv, NULL);
  53   return (tv.tv_sec * 1000LL) + (tv.tv_usec / 1000LL);
  54 #elif defined (HAVE_TIME)
  55   return time (NULL) * 1000LL;
  56 #elif defined (HAVE_FTIME)
  57   struct timeb t;
  58   ftime (&t);
  59   return (t.time * 1000LL) + t.millitm;
  60 #elif defined (ECOS)
  61   // FIXME.
  62   return _clock();
  63 #else
  64   // In the absence of any function, time remains forever fixed.
  65   return 23000;
  66 #endif
  67 }
  68
  69 // Platform-specific VM initialization.
  70 void
  71 _Jv_platform_initialize (void)
  72 {
  73 #if defined (HAVE_SIGACTION)
  74   // We only want this on POSIX systems.
  75   struct sigaction act;
  76   act.sa_handler = SIG_IGN;
  77   sigemptyset (&act.sa_mask);
  78   act.sa_flags = 0;
  79   sigaction (SIGPIPE, &act, NULL);
  80 #else
  81   signal (SIGPIPE, SIG_IGN);
  82 #endif
  83
  84 #if defined (HAVE_PROC_SELF_EXE)
  85   // Compute our executable name
  86   sprintf (exec_name, "/proc/%d/exe", getpid ());
  87 #endif
  88 }
  89
  90 // Set platform-specific System properties.
  91 void
  92 _Jv_platform_initProperties (java::util::Properties* newprops)
  93 {
  94   // A convenience define.
  95 #define SET(Prop,Val) \
  96   newprops->put(JvNewStringLatin1 (Prop), JvNewStringLatin1 (Val))
  97
  98   SET ("file.separator", "/");
  99   SET ("path.separator", ":");
 100   SET ("line.separator", "\n");
 101   char *tmpdir = ::getenv("TMPDIR");
 102   if (! tmpdir)
 103     tmpdir = "/tmp";
 104   SET ("java.io.tmpdir", tmpdir);
 105 }
 106
 107 static inline void
 108 internal_gettimeofday (struct timeval *result)
 109 {
 110 #if defined (HAVE_GETTIMEOFDAY)
 111   gettimeofday (result, NULL);
 112 #else
 113   jlong val = _Jv_platform_gettimeofday ();
 114   result->tv_sec = val / 1000;
 115   result->tv_usec = (val % 1000) * 1000;
 116 #endif /* HAVE_GETTIMEOFDAY */
 117 }
 118
 119 // A wrapper for select() which ignores EINTR.
 120 int
 121 _Jv_select (int n, fd_set *readfds, fd_set  *writefds,
 122             fd_set *exceptfds, struct timeval *timeout)
 123 {
 124 #ifdef HAVE_SELECT
 125   // If we have a timeout, compute the absolute ending time.
 126   struct timeval end, delay;
 127   if (timeout)
 128     {
 129       internal_gettimeofday (&end);
 130       end.tv_usec += timeout->tv_usec;
 131       if (end.tv_usec >= 1000000)
 132         {
 133           ++end.tv_sec;
 134           end.tv_usec -= 1000000;
 135         }
 136       end.tv_sec += timeout->tv_sec;
 137       delay = *timeout;
 138     }
 139   else
 140     {
 141       // Placate compiler.
 142       delay.tv_sec = delay.tv_usec = 0;
 143     }
 144
 145   while (1)
 146     {
 147       int r = select (n, readfds, writefds, exceptfds,
 148                       timeout ? &delay : NULL);
 149       if (r != -1 || errno != EINTR)
 150         return r;
 151
 152       // Here we know we got EINTR.
 153       if (java::lang::Thread::interrupted ())
 154         throw new java::io::InterruptedIOException (JvNewStringLatin1 ("select interrupted"));
 155
 156       struct timeval after;
 157       if (timeout)
 158         {
 159           internal_gettimeofday (&after);
 160           // Now compute new timeout argument.
 161           delay.tv_usec = end.tv_usec - after.tv_usec;
 162           delay.tv_sec = end.tv_sec - after.tv_sec;
 163           if (delay.tv_usec < 0)
 164             {
 165               --delay.tv_sec;
 166               delay.tv_usec += 1000000;
 167             }
 168           if (delay.tv_sec < 0)
 169             {
 170               // We assume that the user wants a valid select() call
 171               // more than precise timing.  So if we get a series of
 172               // EINTR we just keep trying with delay 0 until we get a
 173               // valid result.
 174               delay.tv_sec = 0;
 175             }
 176         }
 177     }
 178 #else /* HAVE_SELECT */
 179   return 0;
 180 #endif
 181 }