From ecdc4ca6c18d7ec2160ec104b9c94dbcb866ef9d Mon Sep 17 00:00:00 2001
From: sof <unknown>
Date: Sun, 19 Sep 1999 19:20:50 +0000
Subject: [PATCH] [project @ 1999-09-19 19:20:50 by sof] * drop the restriction
that seeks cannot be made on devices & beyond EOFs. If the underlying
lseek() doesn't like us doing either, it'll let us know. * When asking for
the current position under Win32, take into account that lseek() reports
the _untranslated_ position, so adjust the resulting position by scanning
input buffer looking for \n's (and treat them as if \r\n.)
---
ghc/lib/std/cbits/filePosn.c | 55 +++++++++++++++++++++++++++++++-----
1 file changed, 48 insertions(+), 7 deletions(-)
diff --git a/ghc/lib/std/cbits/filePosn.c b/ghc/lib/std/cbits/filePosn.c
index fefdaf6ea22a..c3b130b063ae 100644
--- a/ghc/lib/std/cbits/filePosn.c
+++ b/ghc/lib/std/cbits/filePosn.c
@@ -1,7 +1,7 @@
/*
* (c) The GRASP/AQUA Project, Glasgow University, 1994-1998
*
- * $Id: filePosn.c,v 1.3 1998/12/02 13:27:27 simonm Exp $
+ * $Id: filePosn.c,v 1.4 1999/09/19 19:20:50 sof Exp $
*
* hGetPosn and hSetPosn Runtime Support
*/
@@ -14,7 +14,7 @@ getFilePosn(ptr)
StgForeignPtr ptr;
{
IOFileObject* fo = (IOFileObject*)ptr;
- StgInt posn;
+ off_t posn;
while ( (posn = lseek(fo->fd, 0, SEEK_CUR)) == -1) {
if (errno != EINTR) {
@@ -27,25 +27,66 @@ StgForeignPtr ptr;
posn += fo->bufWPtr;
} else if (fo->flags & FILEOBJ_READ) {
posn -= (fo->bufWPtr - fo->bufRPtr);
+#if defined(_WIN32)
+ if (!(fo->flags & FILEOBJ_BINARY)) {
+ /* Sigh, to get at the Real file position for files opened
+ in text mode, we need to scan the read buffer looking for
+ '\n's, making them count as \r\n (i.e., undoing the work of
+ read()), since lseek() returns the raw position.
+ */
+ int i, j;
+ i = fo->bufRPtr;
+ j = fo->bufWPtr;
+ while (i <= j) {
+ if (((char*)fo->buf)[i] == '\n') {
+ posn--;
+ }
+ i++;
+ }
+ }
+#endif
}
- return posn;
+ return (StgInt)posn;
}
/* The following is only called with a position that we've already visited
(this is ensured by making the Haskell file posn. type abstract.)
*/
StgInt
-setFilePosn(ptr, posn)
+setFilePosn(ptr, size, d)
StgForeignPtr ptr;
-StgInt posn;
+StgInt size;
+StgByteArray d;
{
IOFileObject* fo = (IOFileObject*)ptr;
- int rc;
+ int rc, mode;
+ off_t offset;
+
+ /*
+ * We need to snatch the offset out of an MP_INT. The bits are there sans sign,
+ * which we pick up from our size parameter. If abs(size) is greater than 1,
+ * this integer is just too big.
+ */
+ switch (size) {
+ case -1:
+ offset = -*(StgInt *) d;
+ break;
+ case 0:
+ offset = 0;
+ break;
+ case 1:
+ offset = *(StgInt *) d;
+ break;
+ default:
+ ghc_errtype = ERR_INVALIDARGUMENT;
+ ghc_errstr = "offset out of range";
+ return -1;
+ }
rc = flushBuffer(ptr);
if (rc < 0) return rc;
- while (lseek(fo->fd, posn, SEEK_SET) == -1) {
+ while (lseek(fo->fd, offset, SEEK_SET) == -1) {
if (errno != EINTR) {
cvtErrno();
stdErrno();
--
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