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Diffstat (limited to 'ghc/lib/std/cbits/lockFile.c')
-rw-r--r--ghc/lib/std/cbits/lockFile.c128
1 files changed, 0 insertions, 128 deletions
diff --git a/ghc/lib/std/cbits/lockFile.c b/ghc/lib/std/cbits/lockFile.c
deleted file mode 100644
index f6a9aea4ad..0000000000
--- a/ghc/lib/std/cbits/lockFile.c
+++ /dev/null
@@ -1,128 +0,0 @@
-/*
- * (c) The GRASP/AQUA Project, Glasgow University, 1994-1998
- *
- * $Id: lockFile.c,v 1.2 2001/05/21 11:02:15 simonmar Exp $
- *
- * stdin/stout/stderr Runtime Support
- */
-
-#include "HsStd.h"
-
-#ifndef FD_SETSIZE
-#define FD_SETSIZE 256
-#endif
-
-typedef struct {
- dev_t device;
- ino_t inode;
- int fd;
-} Lock;
-
-static Lock readLock[FD_SETSIZE];
-static Lock writeLock[FD_SETSIZE];
-
-static int readLocks = 0;
-static int writeLocks = 0;
-
-int
-lockFile(int fd, int for_writing, int exclusive)
-{
- struct stat sb;
- int i;
-
- while (fstat(fd, &sb) < 0) {
- if (errno != EINTR) {
-#ifndef _WIN32
- return -1;
-#else
- /* fstat()ing socket fd's seems to fail with CRT's fstat(),
- so let's just silently return and hope for the best..
- */
- return 0;
-#endif
- }
- }
-
- if (for_writing) {
- /* opening a file for writing, check to see whether
- we don't have any read locks on it already.. */
- for (i = 0; i < readLocks; i++) {
- if (readLock[i].inode == sb.st_ino && readLock[i].device == sb.st_dev) {
-#ifndef __MINGW32__
- return -1;
-#else
- break;
-#endif
- }
- }
- /* If we're determined that there is only a single
- writer to the file, check to see whether the file
- hasn't already been opened for writing..
- */
- if (exclusive) {
- for (i = 0; i < writeLocks; i++) {
- if (writeLock[i].inode == sb.st_ino && writeLock[i].device == sb.st_dev) {
-#ifndef __MINGW32__
- return -1;
-#else
- break;
-#endif
- }
- }
- }
- /* OK, everything is cool lock-wise, record it and leave. */
- i = writeLocks++;
- writeLock[i].device = sb.st_dev;
- writeLock[i].inode = sb.st_ino;
- writeLock[i].fd = fd;
- return 0;
- } else {
- /* For reading, it's simpler - just check to see
- that there's no-one writing to the underlying file. */
- for (i = 0; i < writeLocks; i++) {
- if (writeLock[i].inode == sb.st_ino && writeLock[i].device == sb.st_dev) {
-#ifndef __MINGW32__
- return -1;
-#else
- break;
-#endif
- }
- }
- /* Fit in new entry, reusing an existing table entry, if possible. */
- for (i = 0; i < readLocks; i++) {
- if (readLock[i].inode == sb.st_ino && readLock[i].device == sb.st_dev) {
- return 0;
- }
- }
- i = readLocks++;
- readLock[i].device = sb.st_dev;
- readLock[i].inode = sb.st_ino;
- readLock[i].fd = fd;
- return 0;
- }
-
-}
-
-int
-unlockFile(int fd)
-{
- int i;
-
- for (i = 0; i < readLocks; i++)
- if (readLock[i].fd == fd) {
- while (++i < readLocks)
- readLock[i - 1] = readLock[i];
- readLocks--;
- return 0;
- }
-
- for (i = 0; i < writeLocks; i++)
- if (writeLock[i].fd == fd) {
- while (++i < writeLocks)
- writeLock[i - 1] = writeLock[i];
- writeLocks--;
- return 0;
- }
- /* Signal that we did not find an entry */
- return 1;
-}