[project @ 1999-11-25 16:54:14 by simonmar]

[ghc-hetmet.git] / ghc / lib / std / cbits / openFile.c

diff --git a/ghc/lib/std/cbits/openFile.c b/ghc/lib/std/cbits/openFile.c
index 2d5afe5..d1b0d6d 100644 (file)
--- a/ghc/lib/std/cbits/openFile.c
+++ b/ghc/lib/std/cbits/openFile.c
@@ -1,7 +1,7 @@
 /* 
  * (c) The GRASP/AQUA Project, Glasgow University, 1994-1998
  *
- * $Id: openFile.c,v 1.5 1999/01/23 17:44:40 sof Exp $
+ * $Id: openFile.c,v 1.11 1999/11/25 16:54:14 simonmar Exp $
  *
  * openFile Runtime Support
  */
@@ -29,13 +29,17 @@
 #include <fcntl.h>
 #endif
 
+#if defined(mingw32_TARGET_OS) && !defined(O_NOCTTY)
+#define O_NOCTTY 0
+#endif
+
 IOFileObject*
-openStdFile(fd,flags,rd)
+openStdFile(fd,rd)
 StgInt fd;
-StgInt flags;
 StgInt rd;
 {
     IOFileObject* fo;
+    long fd_flags;
 
     if ((fo = malloc(sizeof(IOFileObject))) == NULL)
        return NULL;
@@ -43,9 +47,20 @@ StgInt rd;
     fo->buf      = NULL;
     fo->bufWPtr  = 0;
     fo->bufRPtr  = 0;
-    fo->flags   = flags | FILEOBJ_STD | ( rd ? FILEOBJ_READ : FILEOBJ_WRITE);
+    fo->flags    = FILEOBJ_STD | ( rd ? FILEOBJ_READ : FILEOBJ_WRITE);
     fo->connectedTo = NULL;
-    return fo;
+ 
+    /* MS Win32 CRT doesn't support fcntl() -- the workaround is to
+       start using 'completion ports', but I'm punting on implementing
+       support for using those.
+    */
+#if !defined(_WIN32) || defined(__CYGWIN__) || defined(__CYGWIN32__)
+    /* set the non-blocking flag on this file descriptor */
+    fd_flags = fcntl(fd, F_GETFL);
+    fcntl(fd, F_SETFL, fd_flags | O_NONBLOCK);
+#endif
+
+   return fo;
 }
 
 #define OPENFILE_APPEND 0
@@ -54,19 +69,23 @@ StgInt rd;
 #define OPENFILE_READ_WRITE 3
 
 IOFileObject*
-openFile(file, how, binary, flags)
+openFile(file, how, binary)
 StgByteArray file;
 StgInt how;
 StgInt binary;
-StgInt flags;
 {
     FILE *fp;
     int fd;
     int oflags;
-    int exclusive;
+    int for_writing;
     int created = 0;
     struct stat sb;
     IOFileObject* fo;
+    int flags = 0;
+
+#if defined(_WIN32) && !(defined(__CYGWIN__) || defined(__CYGWIN32__))
+#define O_NONBLOCK 0
+#endif
 
     /*
      * Since we aren't supposed to succeed when we're opening for writing and
@@ -75,20 +94,24 @@ StgInt flags;
 
     switch (how) {
       case OPENFILE_APPEND:
-        oflags = O_WRONLY | O_NOCTTY | O_APPEND; 
-       exclusive = 1;
+        oflags = O_NONBLOCK | O_WRONLY | O_NOCTTY | O_APPEND; 
+       for_writing = 1;
+       flags |= FILEOBJ_WRITE;
        break;
       case OPENFILE_WRITE:
-       oflags = O_WRONLY | O_NOCTTY;
-       exclusive = 1;
+       oflags = O_NONBLOCK | O_WRONLY | O_NOCTTY;
+       flags |= FILEOBJ_WRITE;
+       for_writing = 1;
        break;
     case OPENFILE_READ_ONLY:
-        oflags = O_RDONLY | O_NOCTTY;
-       exclusive = 0;
+        oflags = O_NONBLOCK | O_RDONLY | O_NOCTTY;
+       flags |= FILEOBJ_READ;
+       for_writing = 0;
        break;
     case OPENFILE_READ_WRITE:
-       oflags = O_RDWR | O_NOCTTY;
-       exclusive = 0;
+       oflags = O_NONBLOCK | O_RDWR | O_NOCTTY;
+       flags |= FILEOBJ_READ | FILEOBJ_WRITE;
+       for_writing = 1;
        break;
     default:
        fprintf(stderr, "openFile: unknown mode `%d'\n", how);
@@ -96,8 +119,10 @@ StgInt flags;
     }
 
 #if HAVE_O_BINARY
-    if (binary) 
+    if (binary) {
       oflags |= O_BINARY;
+      flags  |= FILEOBJ_BINARY;
+    }
 #endif
 
     /* First try to open without creating */
@@ -110,12 +135,14 @@ StgInt flags;
                return NULL;
            } else {
                /* If it is a dangling symlink, break off now, too. */
+#ifndef mingw32_TARGET_OS
                struct stat st;
                if ( lstat(file,&st) == 0) {
                   ghc_errtype = ERR_NOSUCHTHING;
                   ghc_errstr = "dangling symlink";
                   return NULL;
                }
+#endif
             }
            /* Now try to create it */
            while ((fd = open(file, oflags | O_CREAT | O_EXCL, 0666)) < 0) {
@@ -186,7 +213,7 @@ StgInt flags;
     }
     /* Use our own personal locking */
 
-    if (lockFile(fd, exclusive) < 0) {
+    if (lockFile(fd, for_writing, 1/*enforce single-writer, if needs be.*/) < 0) {
        cvtErrno();
        switch (ghc_errno) {
        default:
@@ -253,26 +280,25 @@ StgInt flags;
 
     fo->fd       = fd;
     fo->buf      = NULL;
+    fo->bufStart = 0;
     fo->bufWPtr  = 0;
     fo->bufRPtr  = 0;
-    fo->flags   = flags | ( (how == OPENFILE_READ_ONLY || how == OPENFILE_READ_WRITE) ? FILEOBJ_READ  : 0)
-                       | ( (how == OPENFILE_APPEND    || how == OPENFILE_READ_WRITE) ? FILEOBJ_WRITE : 0);
+    fo->flags    = flags;
     fo->connectedTo = NULL;
     return fo;
 }
 
 /* `Lock' file descriptor and return file object. */
 IOFileObject*
-openFd(fd,oflags,flags)
-StgInt fd;
-StgInt oflags;
-StgInt flags;
+openFd(StgInt fd,StgInt oflags,StgInt flags)
 {
-    int exclusive;
+    int for_writing;
     FILE* fp;
     IOFileObject* fo;
 
-    if (lockFile(fd, exclusive) < 0) {
+    for_writing = ( ((oflags & O_WRONLY) || (oflags & O_RDWR)) ? 1 : 0);
+
+    if (lockFile(fd, for_writing, 1/* enforce single-writer */ ) < 0) {
        cvtErrno();
        switch (ghc_errno) {
        default:
@@ -290,11 +316,12 @@ StgInt flags;
     /* See openFileObject() comment */
     if ((fo = malloc(sizeof(IOFileObject))) == NULL)
        return NULL;
-    fo->fd      = fd;
-    fo->buf     = NULL;
-    fo->bufWPtr = 0;
-    fo->bufRPtr = 0;
-    fo->flags   = flags | ( oflags & O_RDONLY ? FILEOBJ_READ 
+    fo->fd       = fd;
+    fo->buf      = NULL;
+    fo->bufStart = 0;
+    fo->bufWPtr  = 0;
+    fo->bufRPtr  = 0;
+    fo->flags    = flags | ( oflags & O_RDONLY ? FILEOBJ_READ 
                          : oflags & O_RDWR   ? FILEOBJ_READ 
                          : 0)
                        | ( oflags & O_WRONLY ? FILEOBJ_WRITE