[SETUPLIB][USETUP] Reduce duplicated code

- ScrollDownPartitionList() and ScrollUpPartitionList()
--> ScrollUpDownPartitionList()

- GetPrimaryPartitionCount() and GetLogicalPartitionCount()
--> generic GetPartitionCount() and macros.

- GetPrevUnpartitionedEntry() and GetNextUnpartitionedEntry()
--> GetAdjUnpartitionedEntry() ("Adj" == Adjacent)

base/setup/lib/utils/arcname.c

···
     BOOLEAN UseSignature;
     SIZE_T NameLength;
 
-    PDISKENTRY DiskEntry;
-    PPARTENTRY PartEntry = NULL;
-
     if (NtName->MaximumLength < sizeof(UNICODE_NULL))
         return STATUS_BUFFER_TOO_SMALL;
 
···
     else
     if (PeripheralType == RDiskPeripheral)
     {
+        PDISKENTRY DiskEntry;
+        PPARTENTRY PartEntry = NULL;
+
         if (UseSignature)
         {
             /* The disk signature is stored in AdapterKey */

base/setup/lib/utils/partlist.c

···
 //        PartitionInfo->PartitionType == PartEntry->PartitionType
 }
 
+
+/**
+ * @brief
+ * Counts the number of partitioned disk regions in a given partition list.
+ **/
 static
 ULONG
-GetPrimaryPartitionCount(
-    IN PDISKENTRY DiskEntry)
+GetPartitionCount(
+    _In_ PLIST_ENTRY PartListHead)
 {
     PLIST_ENTRY Entry;
     PPARTENTRY PartEntry;
     ULONG Count = 0;
 
-    if (DiskEntry->DiskStyle == PARTITION_STYLE_GPT)
-    {
-        DPRINT("GPT-partitioned disk detected, not currently supported by SETUP!\n");
-        return 0;
-    }
-
-    for (Entry = DiskEntry->PrimaryPartListHead.Flink;
-         Entry != &DiskEntry->PrimaryPartListHead;
+    for (Entry = PartListHead->Flink;
+         Entry != PartListHead;
          Entry = Entry->Flink)
     {
         PartEntry = CONTAINING_RECORD(Entry, PARTENTRY, ListEntry);
         if (PartEntry->IsPartitioned)
-            Count++;
+            ++Count;
     }
 
     return Count;
 }
 
-static
-ULONG
-GetLogicalPartitionCount(
-    IN PDISKENTRY DiskEntry)
-{
-    PLIST_ENTRY ListEntry;
-    PPARTENTRY PartEntry;
-    ULONG Count = 0;
+#define GetPrimaryPartitionCount(DiskEntry) \
+    GetPartitionCount(&(DiskEntry)->PrimaryPartListHead)
 
-    if (DiskEntry->DiskStyle == PARTITION_STYLE_GPT)
-    {
-        DPRINT("GPT-partitioned disk detected, not currently supported by SETUP!\n");
-        return 0;
-    }
+#define GetLogicalPartitionCount(DiskEntry) \
+    (((DiskEntry)->DiskStyle == PARTITION_STYLE_MBR) \
+        ? GetPartitionCount(&(DiskEntry)->LogicalPartListHead) : 0)
 
-    for (ListEntry = DiskEntry->LogicalPartListHead.Flink;
-         ListEntry != &DiskEntry->LogicalPartListHead;
-         ListEntry = ListEntry->Flink)
-    {
-        PartEntry = CONTAINING_RECORD(ListEntry, PARTENTRY, ListEntry);
-        if (PartEntry->IsPartitioned)
-            Count++;
-    }
-
-    return Count;
-}
 
 static
 BOOLEAN
···
 #endif
 }
 
+/**
+ * @brief
+ * Retrieves, if any, the unpartitioned disk region that is adjacent
+ * (next or previous) to the specified partition.
+ *
+ * @param[in]   PartEntry
+ * Partition from where to find the adjacent unpartitioned region.
+ *
+ * @param[in]   Direction
+ * TRUE or FALSE to search the next or previous region, respectively.
+ *
+ * @return  The adjacent unpartitioned region, if it exists, or NULL.
+ **/
 static
 PPARTENTRY
-GetPrevUnpartitionedEntry(
-    IN PPARTENTRY PartEntry)
+GetAdjUnpartitionedEntry(
+    _In_ PPARTENTRY PartEntry,
+    _In_ BOOLEAN Direction)
 {
     PDISKENTRY DiskEntry = PartEntry->DiskEntry;
-    PPARTENTRY PrevPartEntry;
-    PLIST_ENTRY ListHead;
+    PLIST_ENTRY ListHead, AdjEntry;
 
-    if (DiskEntry->DiskStyle == PARTITION_STYLE_GPT)
+    /* In case of MBR disks only, check the logical partitions if necessary */
+    if ((DiskEntry->DiskStyle == PARTITION_STYLE_MBR) &&
+        PartEntry->LogicalPartition)
     {
-        DPRINT("GPT-partitioned disk detected, not currently supported by SETUP!\n");
-        return NULL;
-    }
-
-    if (PartEntry->LogicalPartition)
         ListHead = &DiskEntry->LogicalPartListHead;
+    }
     else
-        ListHead = &DiskEntry->PrimaryPartListHead;
-
-    if (PartEntry->ListEntry.Blink != ListHead)
     {
-        PrevPartEntry = CONTAINING_RECORD(PartEntry->ListEntry.Blink,
-                                          PARTENTRY,
-                                          ListEntry);
-        if (!PrevPartEntry->IsPartitioned)
-        {
-            ASSERT(PrevPartEntry->PartitionType == PARTITION_ENTRY_UNUSED);
-            return PrevPartEntry;
-        }
+        ListHead = &DiskEntry->PrimaryPartListHead;
     }
 
-    return NULL;
-}
-
-static
-PPARTENTRY
-GetNextUnpartitionedEntry(
-    IN PPARTENTRY PartEntry)
-{
-    PDISKENTRY DiskEntry = PartEntry->DiskEntry;
-    PPARTENTRY NextPartEntry;
-    PLIST_ENTRY ListHead;
-
-    if (DiskEntry->DiskStyle == PARTITION_STYLE_GPT)
-    {
-        DPRINT("GPT-partitioned disk detected, not currently supported by SETUP!\n");
-        return NULL;
-    }
-
-    if (PartEntry->LogicalPartition)
-        ListHead = &DiskEntry->LogicalPartListHead;
+    if (Direction)
+        AdjEntry = PartEntry->ListEntry.Flink; // Next region.
     else
-        ListHead = &DiskEntry->PrimaryPartListHead;
+        AdjEntry = PartEntry->ListEntry.Blink; // Previous region.
 
-    if (PartEntry->ListEntry.Flink != ListHead)
+    if (AdjEntry != ListHead)
     {
-        NextPartEntry = CONTAINING_RECORD(PartEntry->ListEntry.Flink,
-                                          PARTENTRY,
-                                          ListEntry);
-        if (!NextPartEntry->IsPartitioned)
+        PartEntry = CONTAINING_RECORD(AdjEntry, PARTENTRY, ListEntry);
+        if (!PartEntry->IsPartitioned)
         {
-            ASSERT(NextPartEntry->PartitionType == PARTITION_ENTRY_UNUSED);
-            return NextPartEntry;
+            ASSERT(PartEntry->PartitionType == PARTITION_ENTRY_UNUSED);
+            return PartEntry;
         }
     }
-
     return NULL;
 }
 
···
     /* Adjust the unpartitioned disk space entries */
 
     /* Get pointer to previous and next unpartitioned entries */
-    PrevPartEntry = GetPrevUnpartitionedEntry(PartEntry);
-    NextPartEntry = GetNextUnpartitionedEntry(PartEntry);
+    PrevPartEntry = GetAdjUnpartitionedEntry(PartEntry, FALSE);
+    NextPartEntry = GetAdjUnpartitionedEntry(PartEntry, TRUE);
 
     if (PrevPartEntry != NULL && NextPartEntry != NULL)
     {

base/setup/usetup/partlist.c

···
     }
 }
 
-VOID
-ScrollDownPartitionList(
-    IN PPARTLIST_UI ListUi)
-{
-    PPARTENTRY NextPart = GetNextPartition(ListUi->List, ListUi->CurrentPartition);
-    if (NextPart)
-    {
-        ListUi->CurrentPartition = NextPart;
-        ListUi->CurrentDisk = NextPart->DiskEntry;
-        DrawPartitionList(ListUi);
-    }
-}
-
+/**
+ * @param[in]   Direction
+ * TRUE or FALSE to scroll to the next (down) or previous (up) entry, respectively.
+ **/
 VOID
-ScrollUpPartitionList(
-    IN PPARTLIST_UI ListUi)
+ScrollUpDownPartitionList(
+    _In_ PPARTLIST_UI ListUi,
+    _In_ BOOLEAN Direction)
 {
-    PPARTENTRY PrevPart = GetPrevPartition(ListUi->List, ListUi->CurrentPartition);
-    if (PrevPart)
+    PPARTENTRY PartEntry =
+        (Direction ? GetNextPartition
+                   : GetPrevPartition)(ListUi->List, ListUi->CurrentPartition);
+    if (PartEntry)
     {
-        ListUi->CurrentPartition = PrevPart;
-        ListUi->CurrentDisk = PrevPart->DiskEntry;
+        ListUi->CurrentPartition = PartEntry;
+        ListUi->CurrentDisk = PartEntry->DiskEntry;
         DrawPartitionList(ListUi);
     }
 }

base/setup/usetup/partlist.h

···
     IN SHORT Bottom);
 
 VOID
-ScrollDownPartitionList(
+DrawPartitionList(
     IN PPARTLIST_UI ListUi);
 
 VOID
-ScrollUpPartitionList(
-    IN PPARTLIST_UI ListUi);
-
-VOID
-DrawPartitionList(
-    IN PPARTLIST_UI ListUi);
+ScrollUpDownPartitionList(
+    _In_ PPARTLIST_UI ListUi,
+    _In_ BOOLEAN Direction);
 
 /* EOF */

base/setup/usetup/usetup.c

···
         else if ((Ir->Event.KeyEvent.uChar.AsciiChar == 0x00) &&
                  (Ir->Event.KeyEvent.wVirtualKeyCode == VK_DOWN))  /* DOWN */
         {
-            ScrollDownPartitionList(&ListUi);
+            ScrollUpDownPartitionList(&ListUi, TRUE);
         }
         else if ((Ir->Event.KeyEvent.uChar.AsciiChar == 0x00) &&
                  (Ir->Event.KeyEvent.wVirtualKeyCode == VK_UP))  /* UP */
         {
-            ScrollUpPartitionList(&ListUi);
+            ScrollUpDownPartitionList(&ListUi, FALSE);
         }
         else if (Ir->Event.KeyEvent.wVirtualKeyCode == VK_RETURN)  /* ENTER */
         {