From a927f1d071f9315c97bcbfa23e27aef73a4e07ee Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Herm=C3=A8s=20B=C3=A9lusca-Ma=C3=AFto?=
 <hermes.belusca-maito@reactos.org>
Date: Fri, 13 Sep 2013 22:02:07 +0000
Subject: [PATCH] [MOUNTMGR] - Clarify the code (use properly
 RtlPrefixUnicodeString) - 'if' level--;

svn path=/trunk/; revision=60083
---
 reactos/drivers/filters/mountmgr/device.c   | 10 +++-
 reactos/drivers/filters/mountmgr/mountmgr.c | 17 ++++---
 reactos/drivers/filters/mountmgr/symlink.c  | 51 ++++++++++-----------
 3 files changed, 43 insertions(+), 35 deletions(-)

diff --git a/reactos/drivers/filters/mountmgr/device.c b/reactos/drivers/filters/mountmgr/device.c
index f898bfa5b74..9efdf076e41 100644
--- a/reactos/drivers/filters/mountmgr/device.c
+++ b/reactos/drivers/filters/mountmgr/device.c
@@ -555,13 +555,21 @@ MountMgrNextDriveLetterWorker(IN PDEVICE_EXTENSION DeviceExtension,
     }
 
     /* Now everything is fine, start processing */
+
     if (RtlPrefixUnicodeString(&DeviceFloppy, &TargetDeviceName, TRUE))
     {
+        /* If the device is a floppy, start with letter A */
         DriveLetter = 'A';
     }
+    else if (RtlPrefixUnicodeString(&DeviceCdRom, &TargetDeviceName, TRUE))
+    {
+        /* If the device is a CD-ROM, start with letter D */
+        DriveLetter = 'D';
+    }
     else
     {
-        DriveLetter = 'C' + RtlPrefixUnicodeString(&DeviceCdRom, &TargetDeviceName, TRUE);
+        /* Finally, if it's a disk, use C */
+        DriveLetter = 'C';
     }
 
     /* We cannot set NO drive letter */
diff --git a/reactos/drivers/filters/mountmgr/mountmgr.c b/reactos/drivers/filters/mountmgr/mountmgr.c
index b0a2b31428a..2e78d4e3cbc 100644
--- a/reactos/drivers/filters/mountmgr/mountmgr.c
+++ b/reactos/drivers/filters/mountmgr/mountmgr.c
@@ -169,19 +169,22 @@ CreateNewDriveLetterName(OUT PUNICODE_STRING DriveLetter,
         }
     }
 
-    /* If caller didn't provide a letter, let's find one for him.
-     * If device is a floppy, start with letter A
-     */
+    /* If caller didn't provide a letter, let's find one for him */
+
     if (RtlPrefixUnicodeString(&DeviceFloppy, DeviceName, TRUE))
     {
+        /* If the device is a floppy, start with letter A */
         Letter = 'A';
     }
+    else if (RtlPrefixUnicodeString(&DeviceCdRom, DeviceName, TRUE))
+    {
+        /* If the device is a CD-ROM, start with letter D */
+        Letter = 'D';
+    }
     else
     {
-        /* Otherwise, if device is a cd rom, then, start with D.
-         * Finally, if a disk, use C
-         */
-        Letter = RtlPrefixUnicodeString(&DeviceCdRom, DeviceName, TRUE) + 'C';
+        /* Finally, if it's a disk, use C */
+        Letter = 'C';
     }
 
     /* Try to affect a letter (up to Z, ofc) until it's possible */
diff --git a/reactos/drivers/filters/mountmgr/symlink.c b/reactos/drivers/filters/mountmgr/symlink.c
index 99d5fa4977a..f5b76e69bc8 100644
--- a/reactos/drivers/filters/mountmgr/symlink.c
+++ b/reactos/drivers/filters/mountmgr/symlink.c
@@ -67,38 +67,35 @@ CreateStringWithGlobal(IN PUNICODE_STRING DosName,
                       DosName->Length - DosDevices.Length);
         IntGlobal.Buffer[IntGlobal.Length / sizeof(WCHAR)] = UNICODE_NULL;
     }
+    else if (RtlPrefixUnicodeString(&Global, DosName, TRUE))
+    {
+        /* Switch to DOS global */
+        IntGlobal.Length = DosName->Length - Global.Length + DosGlobal.Length;
+        IntGlobal.MaximumLength = IntGlobal.Length + sizeof(WCHAR);
+        IntGlobal.Buffer = AllocatePool(IntGlobal.MaximumLength);
+        if (!IntGlobal.Buffer)
+        {
+            return STATUS_INSUFFICIENT_RESOURCES;
+        }
+
+        RtlCopyMemory(IntGlobal.Buffer, DosGlobal.Buffer, DosGlobal.Length);
+        RtlCopyMemory(IntGlobal.Buffer + (DosGlobal.Length / sizeof(WCHAR)),
+                      DosName->Buffer + (Global.Length / sizeof(WCHAR)),
+                      DosName->Length - Global.Length);
+        IntGlobal.Buffer[IntGlobal.Length / sizeof(WCHAR)] = UNICODE_NULL;
+    }
     else
     {
-        if (RtlPrefixUnicodeString(&Global, DosName, TRUE))
+        /* Simply duplicate string */
+        IntGlobal.Length = DosName->Length;
+        IntGlobal.MaximumLength = DosName->MaximumLength;
+        IntGlobal.Buffer = AllocatePool(IntGlobal.MaximumLength);
+        if (!IntGlobal.Buffer)
         {
-            /* Switch to DOS global */
-            IntGlobal.Length = DosName->Length - Global.Length + DosGlobal.Length;
-            IntGlobal.MaximumLength = IntGlobal.Length + sizeof(WCHAR);
-            IntGlobal.Buffer = AllocatePool(IntGlobal.MaximumLength);
-            if (!IntGlobal.Buffer)
-            {
-                return STATUS_INSUFFICIENT_RESOURCES;
-            }
-
-            RtlCopyMemory(IntGlobal.Buffer, DosGlobal.Buffer, DosGlobal.Length);
-            RtlCopyMemory(IntGlobal.Buffer + (DosGlobal.Length / sizeof(WCHAR)),
-                          DosName->Buffer + (Global.Length / sizeof(WCHAR)),
-                          DosName->Length - Global.Length);
-            IntGlobal.Buffer[IntGlobal.Length / sizeof(WCHAR)] = UNICODE_NULL;
+            return STATUS_INSUFFICIENT_RESOURCES;
         }
-        else
-        {
-            /* Simply duplicate string */
-            IntGlobal.Length = DosName->Length;
-            IntGlobal.MaximumLength = DosName->MaximumLength;
-            IntGlobal.Buffer = AllocatePool(IntGlobal.MaximumLength);
-            if (!IntGlobal.Buffer)
-            {
-                return STATUS_INSUFFICIENT_RESOURCES;
-            }
 
-            RtlCopyMemory(IntGlobal.Buffer, DosName->Buffer, IntGlobal.MaximumLength);
-        }
+        RtlCopyMemory(IntGlobal.Buffer, DosName->Buffer, IntGlobal.MaximumLength);
     }
 
     /* Return string */