[project @ 1998-12-02 13:17:09 by simonm]

Move 4.01 onto the main trunk.

1 files changed, 307 insertions, 0 deletions

diff --git a/ghc/lib/std/cbits/openFile.c b/ghc/lib/std/cbits/openFile.c
new file mode 100644
index 0000000000..ae4d28724a
--- /dev/null
+++ b/ghc/lib/std/cbits/openFile.c
@@ -0,0 +1,307 @@
+/* 
+ * (c) The GRASP/AQUA Project, Glasgow University, 1994-1998
+ *
+ * $Id: openFile.c,v 1.3 1998/12/02 13:27:44 simonm Exp $
+ *
+ * openFile Runtime Support
+ */
+
+#include "Rts.h"
+#include "stgio.h"
+#include "fileObject.h"
+
+#ifdef HAVE_SYS_TYPES_H
+#include <sys/types.h>
+#endif
+
+#ifdef HAVE_SYS_STAT_H
+#include <sys/stat.h>
+#endif
+
+#ifdef HAVE_UNISTD_H
+#include <unistd.h>
+#endif
+
+#ifdef HAVE_FCNTL_H
+#include <fcntl.h>
+#endif
+
+IOFileObject*
+openStdFile(fd,flags,rd)
+StgInt fd;
+StgInt flags;
+StgInt rd;
+{
+    IOFileObject* fo;
+
+    if ((fo = malloc(sizeof(IOFileObject))) == NULL)
+       return NULL;
+    fo->fd       = fd;
+    fo->buf      = NULL;
+    fo->bufWPtr  = 0;
+    fo->bufRPtr  = 0;
+    fo->flags   = flags | FILEOBJ_STD | ( rd ? FILEOBJ_READ : FILEOBJ_WRITE);
+    fo->connectedTo = NULL;
+    return fo;
+}
+
+#define OPENFILE_APPEND 0
+#define OPENFILE_WRITE 1
+#define OPENFILE_READ_ONLY 2
+#define OPENFILE_READ_WRITE 3
+
+IOFileObject*
+openFile(file, how, binary, flags)
+StgByteArray file;
+StgInt how;
+StgInt binary;
+StgInt flags;
+{
+    FILE *fp;
+    int fd;
+    int oflags;
+    int exclusive;
+    int created = 0;
+    struct stat sb;
+    IOFileObject* fo;
+
+#ifdef __CONCURRENT_HASKELL__
+#warning FixMe: Ignoring bogus bit 7 in openFiles 2nd argument
+    how = how & 0x7f;
+#endif
+
+    /*
+     * Since we aren't supposed to succeed when we're opening for writing and
+     * there's another writer, we can't just do an open() with O_WRONLY.
+     */
+
+    switch (how) {
+      case OPENFILE_APPEND:
+        oflags = O_WRONLY | O_NOCTTY | O_APPEND; 
+	exclusive = 1;
+	break;
+      case OPENFILE_WRITE:
+	oflags = O_WRONLY | O_NOCTTY;
+	exclusive = 1;
+	break;
+    case OPENFILE_READ_ONLY:
+        oflags = O_RDONLY | O_NOCTTY;
+	exclusive = 0;
+	break;
+    case OPENFILE_READ_WRITE:
+	oflags = O_RDWR | O_NOCTTY;
+	exclusive = 0;
+	break;
+    default:
+	fprintf(stderr, "openFile: unknown mode `%d'\n", how);
+	exit(EXIT_FAILURE);
+    }
+
+#if HAVE_O_BINARY
+    if (binary) 
+      oflags |= O_BINARY;
+#endif
+
+    /* First try to open without creating */
+    while ((fd = open(file, oflags, 0666)) < 0) {
+	if (errno == ENOENT) {
+	    if ( how == OPENFILE_READ_ONLY ) {
+		/* For ReadMode, just bail out now */
+		ghc_errtype = ERR_NOSUCHTHING;
+		ghc_errstr = "file does not exist";
+		return NULL;
+	    } else {
+		/* If it is a dangling symlink, break off now, too. */
+		struct stat st;
+		if ( lstat(file,&st) == 0) {
+		   ghc_errtype = ERR_NOSUCHTHING;
+		   ghc_errstr = "dangling symlink";
+		   return NULL;
+		}
+            }
+	    /* Now try to create it */
+	    while ((fd = open(file, oflags | O_CREAT | O_EXCL, 0666)) < 0) {
+		if (errno == EEXIST) {
+		    /* Race detected; go back and open without creating it */
+		    break;
+		} else if (errno != EINTR) {
+		    cvtErrno();
+		    switch (ghc_errno) {
+		    default:
+			stdErrno();
+			break;
+		    case GHC_ENOENT:
+		    case GHC_ENOTDIR:
+			ghc_errtype = ERR_NOSUCHTHING;
+			ghc_errstr = "no path to file";
+			break;
+		    case GHC_EINVAL:
+			ghc_errtype = ERR_PERMISSIONDENIED;
+			ghc_errstr = "unsupported owner or group";
+			break;
+		    }
+		    return NULL;
+		}
+	    }
+	    if (fd >= 0) {
+		created = 1;
+		break;
+	    }
+	} else if (errno != EINTR) {
+	    cvtErrno();
+	    switch (ghc_errno) {
+	    default:
+		stdErrno();
+		break;
+	    case GHC_ENOTDIR:
+		ghc_errtype = ERR_NOSUCHTHING;
+		ghc_errstr = "no path to file";
+		break;
+	    case GHC_EINVAL:
+		ghc_errtype = ERR_PERMISSIONDENIED;
+		ghc_errstr = "unsupported owner or group";
+		break;
+	    }
+	    return NULL;
+	}
+    }
+
+    /* Make sure that we aren't looking at a directory */
+
+    while (fstat(fd, &sb) < 0) {
+	/* highly unlikely */
+	if (errno != EINTR) {
+	    cvtErrno();
+	    if (created)
+		(void) unlink(file);
+	    (void) close(fd);
+	    return NULL;
+	}
+    }
+    if (S_ISDIR(sb.st_mode)) {
+	ghc_errtype = ERR_INAPPROPRIATETYPE;
+	ghc_errstr = "file is a directory";
+	/* We can't have created it in this case. */
+	(void) close(fd);
+
+	return NULL;
+    }
+    /* Use our own personal locking */
+
+    if (lockFile(fd, exclusive) < 0) {
+	cvtErrno();
+	switch (ghc_errno) {
+	default:
+	    stdErrno();
+	    break;
+	case GHC_EACCES:
+	case GHC_EAGAIN:
+	    ghc_errtype = ERR_RESOURCEBUSY;
+	    ghc_errstr = "file is locked";
+	    break;
+	}
+	if (created)
+	    (void) unlink(file);
+	(void) close(fd);
+	return NULL;
+    }
+
+    /*
+     * Write mode is supposed to truncate the file.  Unfortunately, our pal
+     * ftruncate() is non-POSIX, so we truncate with a second open, which may fail.
+     */
+
+    if ( how == OPENFILE_WRITE ) {
+	int fd2, oflags2;
+
+	oflags2 = oflags | O_TRUNC;
+	while ((fd2 = open(file, oflags2, 0666)) < 0) {
+	    if (errno != EINTR) {
+		cvtErrno();
+		if (created)
+		    (void) unlink(file);
+		(void) close(fd);
+		switch (ghc_errno) {
+		default:
+		    stdErrno();
+		    break;
+		case GHC_EAGAIN:
+		    ghc_errtype = ERR_RESOURCEBUSY;
+		    ghc_errstr = "enforced lock prevents truncation";
+		    break;
+		case GHC_ENOTDIR:
+		    ghc_errtype = ERR_NOSUCHTHING;
+		    ghc_errstr = "no path to file";
+		    break;
+		case GHC_EINVAL:
+		    ghc_errtype = ERR_PERMISSIONDENIED;
+		    ghc_errstr = "unsupported owner or group";
+		    break;
+		}
+		return NULL;
+	    }
+	}
+	close(fd2);
+    }
+
+    /* Allocate a IOFileObject to hold the information
+       we need to record per-handle for the various C stubs.
+       This chunk of memory is wrapped up inside a foreign object,
+       so it will be finalised and freed properly when we're
+       through with the handle.
+    */
+    if ((fo = malloc(sizeof(IOFileObject))) == NULL)
+       return NULL;
+
+    fo->fd       = fd;
+    fo->buf      = NULL;
+    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->connectedTo = NULL;
+    return fo;
+}
+
+/* `Lock' file descriptor and return file object. */
+IOFileObject*
+openFd(fd,oflags,flags)
+StgInt fd;
+StgInt oflags;
+StgInt flags;
+{
+    int exclusive;
+    FILE* fp;
+    IOFileObject* fo;
+
+    if (lockFile(fd, exclusive) < 0) {
+	cvtErrno();
+	switch (ghc_errno) {
+	default:
+	    stdErrno();
+	    break;
+	case GHC_EACCES:
+	case GHC_EAGAIN:
+	    ghc_errtype = ERR_RESOURCEBUSY;
+	    ghc_errstr = "file is locked";
+	    break;
+	}
+	return NULL;
+    }
+
+    /* 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 
+    			  : oflags & O_RDWR   ? FILEOBJ_READ 
+			  : 0)
+			| ( oflags & O_WRONLY ? FILEOBJ_WRITE
+			  : oflags & O_RDWR   ? FILEOBJ_WRITE 
+			  : 0);
+    fo->connectedTo = NULL;
+    return fo;
+}