/** Table containing all open file descriptors. (Entries are null if the fd is not in use */
FD[] fds; // package-private for UnixRuntime
boolean closeOnExec[];
-
- /** Table of all current file locks held by this process. */
- Seekable.Lock[] locks;
- public static final int LOCK_MAX = 8;
/** Pointer to a SecurityManager for this process */
SecurityManager sm;
r.startTime = 0;
r.fds = new FD[OPEN_MAX];
for(int i=0;i<OPEN_MAX;i++) if(fds[i] != null) r.fds[i] = fds[i].dup();
- r.locks = new Seekable.Lock[LOCK_MAX];
int totalPages = writePages.length;
r.readPages = new int[totalPages][];
r.writePages = new int[totalPages][];
if(!exec) {
fds = new FD[OPEN_MAX];
closeOnExec = new boolean[OPEN_MAX];
- locks = new Seekable.Lock[LOCK_MAX];
InputStream stdin = win32Hacks ? new Win32ConsoleIS(System.in) : System.in;
addFD(new TerminalFD(stdin));
return i;
}
+ /** Hook for subclasses to do something when the process closes an FD */
+ void _closedFD(FD fd) { }
+
/** Closes file descriptor <i>fdn</i> and removes it from the file descriptor table */
public final boolean closeFD(int fdn) {
if(state == EXITED || state == EXECED) throw new IllegalStateException("closeFD called in inappropriate state");
if(fdn < 0 || fdn >= OPEN_MAX) return false;
if(fds[fdn] == null) return false;
- // release all fcntl locks on this file
- Seekable s = fds[fdn].seekable();
- if (s != null) {
- try {
- for (int i=0; i < LOCK_MAX; i++) {
- if (locks[i] != null && s.equals(locks[i].seekable())) {
- locks[i].release();
- locks[i] = null;
- }
- }
- } catch (IOException e) { throw new RuntimeException(e); }
- }
+ _closedFD(fds[fdn]);
fds[fdn].close();
fds[fdn] = null;
return 0;
}
- private int sys_fcntl(int fdn, int cmd, int arg) throws FaultException {
+ final int sys_fcntl(int fdn, int cmd, int arg) throws FaultException {
int i;
if(fdn < 0 || fdn >= OPEN_MAX) return -EBADFD;
return closeOnExec[fdn] ? 1 : 0;
case F_GETLK:
case F_SETLK:
- try {
- return sys_fcntl_lock(fd, cmd, arg);
- } catch (IOException e) { throw new RuntimeException(e);}
+ if(STDERR_DIAG) System.err.println("WARNING: file locking requires UnixRuntime");
+ return -ENOSYS;
default:
if(STDERR_DIAG) System.err.println("WARNING: Unknown fcntl command: " + cmd);
return -ENOSYS;
}
}
- /** Implements the F_GETLK and F_SETLK cases of fcntl syscall.
- * If l_start = 0 and l_len = 0 the lock refers to the entire file.
- struct flock {
- short l_type; // lock type: F_UNLCK, F_RDLCK, F_WRLCK
- short l_whence; // type of l_start: SEEK_SET, SEEK_CUR, SEEK_END
- long l_start; // starting offset, bytes
- long l_len; // len = 0 means until EOF
- short l_pid; // lock owner
- short l_xxx; // padding
- };
- */
- private int sys_fcntl_lock(FD fd, int cmd, int arg)
- throws FaultException, IOException {
- if (arg == 0) { System.out.println("BAD ARG"); return -EINVAL; }
- int word = memRead(arg);
- int l_start = memRead(arg+4);
- int l_len = memRead(arg+8);
- int l_type = word>>16;
- int l_whence = word&0x00ff;
-
- Seekable s = fd.seekable();
- if (s == null) return -EINVAL;
-
- switch (l_whence) {
- case SEEK_SET: break;
- case SEEK_CUR: l_start += s.pos(); break;
- case SEEK_END: l_start += s.length(); break;
- default: return -1;
- }
-
- if (cmd != F_GETLK && cmd != F_SETLK) return -EINVAL;
-
- if (cmd == F_GETLK) {
- // Check if an l_type lock can be aquired. The only way to
- // do this within the Java API is to try and create a lock.
- Seekable.Lock lock = s.lock(l_start, l_len, l_type == F_RDLCK);
-
- if (lock != null) {
- // no lock exists
- memWrite(arg, SEEK_SET|(F_UNLCK<<16));
- lock.release();
- }
-
- return 0;
- }
-
- // now processing F_SETLK
- if (cmd != F_SETLK) return -EINVAL;
-
- if (l_type == F_UNLCK) {
- // release all locks that fall within the boundaries given
- for (int i=0; i < LOCK_MAX; i++) {
- if (locks[i] == null || !s.equals(locks[i].seekable()))
- continue;
-
- int pos = (int)locks[i].position();
- if (pos < l_start) continue;
- if (l_start != 0 && l_len != 0) // start/len 0 means unlock all
- if (pos + locks[i].size() > l_start + l_len)
- continue;
-
- locks[i].release();
- locks[i] = null;
- }
- return 0;
-
- } else if (l_type == F_RDLCK || l_type == F_WRLCK) {
- // first see if a lock already exists
- for (int i=0; i < LOCK_MAX; i++) {
- if (locks[i] == null || !s.equals(locks[i].seekable()))
- continue;
- int pos = (int)locks[i].position();
- int size = (int)locks[i].size();
- if (l_start < pos && pos + size < l_start + l_len) {
- // found a lock contained in the new requested lock
- locks[i].release();
- locks[i] = null;
-
- } else if (l_start >= pos && pos + size >= l_start + l_len) {
- // found a lock that contains the requested lock
- if (locks[i].isShared() == (l_type == F_RDLCK)) {
- memWrite(arg+4, pos);
- memWrite(arg+8, size);
- return 0;
- } else {
- locks[i].release();
- locks[i] = null;
- }
- }
- }
-
- // create the lock
- Seekable.Lock lock = s.lock(l_start, l_len, l_type == F_RDLCK);
- if (lock == null) return -EAGAIN;
-
- int i;
- for (i=0; i < LOCK_MAX; i++)
- if (locks[i] == null) break;
- if (i == LOCK_MAX) return -ENOLCK;
- locks[i] = lock;
- return 0;
-
- } else {
- return -EINVAL;
- }
- }
-
-
/** The syscall dispatcher.
The should be called by subclasses when the syscall instruction is invoked.
<i>syscall</i> should be the contents of V0 and <i>a</i>, <i>b</i>, <i>c</i>, and <i>d</i> should be
projects / nestedvm.git / blobdiff