From: Rod Widdowson <rdw@steadingsoftware.com>
Date: Wed, 27 Oct 2010 22:20:30 +0000 (+0200)
Subject: windows: native versions of ih_pread and ih_pwrite
X-Git-Tag: upstream/1.6.0.pre2^2~81
X-Git-Url: https://git.michaelhowe.org/gitweb/?a=commitdiff_plain;h=3b0dbf3c86b98a66e1723b65da0a2761eeede651;p=packages%2Fo%2Fopenafs.git

windows: native versions of ih_pread and ih_pwrite

Separate the windows code out in ihandle.c to reduce dependency on ntops.

As an aid to future threading issues, pass the offset in an OVERLAP
rather than doing a separate SetFilePointerEx.

Reviewed-on: http://gerrit.openafs.org/3176
Reviewed-by: Derrick Brashear <shadow@dementia.org>
Reviewed-by: Andrew Deason <adeason@sinenomine.net>
Tested-by: Derrick Brashear <shadow@dementia.org>
(cherry picked from commit 50b6a116a1c412d0e6d7442d13d6e92c9dbb35ee)

Change-Id: Iaa340515bf36d249d4f2160b55c3fbb267bb90ee
Reviewed-on: http://gerrit.openafs.org/3825
Tested-by: BuildBot <buildbot@rampaginggeek.com>
Reviewed-by: Derrick Brashear <shadow@dementia.org>
---

diff --git a/src/config/afsconfig-windows.h b/src/config/afsconfig-windows.h
index 32369e690..6e7662c49 100644
--- a/src/config/afsconfig-windows.h
+++ b/src/config/afsconfig-windows.h
@@ -33,6 +33,7 @@
 /* Define as the return type of signal handlers (int or void).  */
 #undef RETSIGTYPE
 
+
 /* The size of `long', as computed by sizeof. */
 #define SIZEOF_LONG 4
 
@@ -162,6 +163,9 @@
 /* define if struct ufsvfs has vfs_dqrwlock */
 #undef HAVE_VFS_DQRWLOCK
 
+/* define if you have pread() and pwrite() */
+#define HAVE_PIO 1
+
 #undef PACKAGE
 #undef VERSION
 
diff --git a/src/vol/ntops.c b/src/vol/ntops.c
index a9e69c984..c14156c93 100644
--- a/src/vol/ntops.c
+++ b/src/vol/ntops.c
@@ -156,6 +156,31 @@ nt_write(FD_t fd, char *buf, size_t size)
     return (int)nbytes;
 }
 
+int
+nt_pwrite(FD_t fd, const void * buf, size_t count, afs_foff_t offset)
+{
+    /*
+     * same comment as read
+     */
+
+    DWORD nbytes;
+    BOOL code;
+    OVERLAPPED overlap = {0};
+    LARGE_INTEGER liOffset;
+
+    liOffset.QuadPart = offset;
+    overlap.Offset = liOffset.LowPart;
+    overlap.OffsetHigh = liOffset.HighPart;
+
+    code = WriteFile((HANDLE) fd, (void *)buf, (DWORD) count, &nbytes, &overlap);
+
+    if (!code) {
+	errno = nterr_nt2unix(GetLastError(), EBADF);
+	return -1;
+    }
+    return (ssize_t)nbytes;
+}
+
 int
 nt_read(FD_t fd, char *buf, size_t size)
 {
@@ -171,6 +196,33 @@ nt_read(FD_t fd, char *buf, size_t size)
     return (int)nbytes;
 }
 
+int
+nt_pread(FD_t fd, void * buf, size_t count, afs_foff_t offset)
+{
+    /*
+     * This really ought to call NtReadFile
+     */
+    DWORD nbytes;
+    BOOL code;
+    OVERLAPPED overlap = {0};
+    LARGE_INTEGER liOffset;
+    /*
+     * Cast through a LARGE_INTEGER - make no assumption about
+     * byte ordering and leave that to the compiler..
+     */
+    liOffset.QuadPart = offset;
+    overlap.Offset = liOffset.LowPart;
+    overlap.OffsetHigh = liOffset.HighPart;
+
+    code = ReadFile((HANDLE) fd, (void *)buf, (DWORD) count, &nbytes, &overlap);
+
+    if (!code) {
+	errno = nterr_nt2unix(GetLastError(), EBADF);
+	return -1;
+    }
+    return (ssize_t)nbytes;
+}
+
 int
 nt_iread(IHandle_t * h, int offset, char *buf, int size)
 {
diff --git a/src/vol/ntops.h b/src/vol/ntops.h
index 8ffa46939..a01c4d9a3 100644
--- a/src/vol/ntops.h
+++ b/src/vol/ntops.h
@@ -25,6 +25,8 @@ extern FD_t nt_open(char *name, int flags, int mode);
 extern int nt_close(FD_t fd);
 extern int nt_write(FD_t fd, char *buf, size_t size);
 extern int nt_read(FD_t fd, char *buf, size_t size);
+extern int nt_pread(FD_t fd, void * buf, size_t count, afs_foff_t offset);
+extern int nt_pwrite(FD_t fd, const void * buf, size_t count, afs_foff_t offset);
 extern int nt_size(FD_t fd);
 extern int nt_getFileCreationTime(FD_t fd, FILETIME * ftime);
 extern int nt_setFileCreationTime(FD_t fd, FILETIME * ftime);