From 75deecc48d0f77370eb65b6ddd44b5ad5749dbcd Mon Sep 17 00:00:00 2001
From: "KJK::Hyperion" <hackbunny@reactos.org>
Date: Thu, 21 Mar 2002 22:46:30 +0000
Subject: [PATCH] implemented read and write system calls

svn path=/trunk/; revision=2755
---
 posix/lib/psxdll/unistd/read.c  | 106 ++++++++++++++++++++++++++------
 posix/lib/psxdll/unistd/write.c |  49 ++++++++++++++-
 2 files changed, 135 insertions(+), 20 deletions(-)

diff --git a/posix/lib/psxdll/unistd/read.c b/posix/lib/psxdll/unistd/read.c
index a3ce7126058..a6d6e0f045d 100644
--- a/posix/lib/psxdll/unistd/read.c
+++ b/posix/lib/psxdll/unistd/read.c
@@ -1,4 +1,4 @@
-/* $Id:
+/* $Id: read.c,v 1.2 2002/03/21 22:46:30 hyperion Exp $
  */
 /*
  * COPYRIGHT:   See COPYING in the top level directory
@@ -11,14 +11,13 @@
  */
 
 #include <ddk/ntddk.h>
+#include <fcntl.h>
 #include <unistd.h>
 #include <sys/types.h>
+#include <psx/debug.h>
+#include <psx/errno.h>
 
-ssize_t read(int fildes, void *buf, size_t nbyte)
-{
-}
-
-ssize_t pread(int fildes, void *buf, size_t nbyte, off_t offset)
+ssize_t __read(int fildes, void *buf, size_t nbyte, off_t *offset)
 {
  HANDLE          hFile;
  NTSTATUS        nErrCode;
@@ -28,22 +27,91 @@ ssize_t pread(int fildes, void *buf, size_t nbyte, off_t offset)
  if(fcntl(fildes, F_GETFH, &hFile) == -1)
   return (-1);
 
- /* read data from file */
- nErrCode = NtReadFile
- (
-  hFile,
-  NULL,
-  NULL,
-  NULL,
-  &isbStatus,
-  buf,
-  nbyte,
-  (PLARGE_INTEGER)&off_t,
-  NULL
- );
+ if(offset != NULL)
+ {
+  /* NT always moves the file pointer, while Unix pread() must not: we have to
+     duplicate the handle and work on the duplicate */ /* FIXME? better save
+     the file position and restore it later? */
+  HANDLE hDupFile;
+
+  /* duplicate the handle */
+  nErrCode = NtDuplicateObject
+  (
+   NtCurrentProcess(),
+   hFile,
+   NtCurrentProcess(),
+   &hDupFile,
+   0,
+   0,
+   DUPLICATE_SAME_ACCESS
+  );
+
+  /* failure */
+  if(!NT_SUCCESS(nErrCode))
+  {
+   errno = __status_to_errno(nErrCode);
+   return (0);
+  }
+
+  /* read data from file at the specified offset */
+  nErrCode = NtReadFile
+  (
+   hDupFile,
+   NULL,
+   NULL,
+   NULL,
+   &isbStatus,
+   buf,
+   nbyte,
+   (PLARGE_INTEGER)offset,
+   NULL
+  );
+
+  NtClose(hDupFile);
+
+  /* failure */
+  if(!NT_SUCCESS(nErrCode))
+  {
+   errno = __status_to_errno(nErrCode);
+   return (0);
+  }
+ }
+ else
+ {
+  /* read data from file at the current offset */
+  nErrCode = NtReadFile
+  (
+   hFile,
+   NULL,
+   NULL,
+   NULL,
+   &isbStatus,
+   buf,
+   nbyte,
+   NULL,
+   NULL
+  );
+
+  /* failure */
+  if(!NT_SUCCESS(nErrCode))
+  {
+   errno = __status_to_errno(nErrCode);
+   return (0);
+  }
+ }
 
  return ((ssize_t)isbStatus.Information);
 }
 
+ssize_t read(int fildes, void *buf, size_t nbyte)
+{
+ return (__read(fildes, buf, nbyte, NULL));
+}
+
+ssize_t pread(int fildes, void *buf, size_t nbyte, off_t offset)
+{
+ return (__read(fildes, buf, nbyte, &offset));
+}
+
 /* EOF */
 
diff --git a/posix/lib/psxdll/unistd/write.c b/posix/lib/psxdll/unistd/write.c
index 25ab55a4f86..9182e26c6be 100644
--- a/posix/lib/psxdll/unistd/write.c
+++ b/posix/lib/psxdll/unistd/write.c
@@ -1,4 +1,4 @@
-/* $Id: write.c,v 1.2 2002/02/20 09:17:58 hyperion Exp $
+/* $Id: write.c,v 1.3 2002/03/21 22:46:30 hyperion Exp $
  */
 /*
  * COPYRIGHT:   See COPYING in the top level directory
@@ -8,8 +8,55 @@
  * PROGRAMMER:  KJK::Hyperion <noog@libero.it>
  * UPDATE HISTORY:
  *              15/02/2002: Created
+ *              21/03/2002: Implemented write() (KJK::Hyperion <noog@libero.it>)
  */
 
+#include <ddk/ntddk.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <sys/types.h>
+#include <psx/debug.h>
+#include <psx/errno.h>
+#include <psx/fdtable.h>
+
+ssize_t write(int fildes, const void *buf, size_t nbyte)
+{
+ __fildes_t      fdDescriptor;
+ NTSTATUS        nErrCode;
+ IO_STATUS_BLOCK isbStatus;
+
+ if(nbyte == 0)
+  return (0);
+
+ if(fcntl(fildes, F_GETALL, &fdDescriptor) == -1)
+  return (0);
+
+ if((fdDescriptor.OpenFlags && O_APPEND) == O_APPEND)
+ {
+  TODO("move file pointer to the end");
+ }
+
+ nErrCode = NtWriteFile
+ (
+  fdDescriptor.FileHandle,
+  NULL,
+  NULL,
+  NULL,
+  &isbStatus,
+  (PVOID)buf,
+  nbyte,
+  NULL,
+  NULL
+ );
+
+ if(!NT_SUCCESS(nErrCode))
+ {
+  errno = __status_to_errno(nErrCode);
+  return (0);
+ }
+
+ return (isbStatus.Information);
+}
 
 /* EOF */
 
-- 
2.17.1