chain: Add DOS partition dumping routine for debugging

Signed-off-by: Shao Miller <shao.miller@yrdsb.edu.on.ca>

diff --git a/com32/modules/chain.c b/com32/modules/chain.c
index d7c6a1c..d5bf4f0 100644 (file)
--- a/com32/modules/chain.c
+++ b/com32/modules/chain.c
@@ -81,6 +81,8 @@
  *      FAT/NTFS boot sector.
  */
 
+#define DEBUG 0                        /* 1 to enable */
+
 #include <com32.h>
 #include <stdlib.h>
 #include <stdio.h>
@@ -364,6 +366,33 @@ struct part_entry {
     uint32_t length;
 } __attribute__ ((packed));
 
+#if DEBUG
+static void mbr_part_dump(const struct part_entry *part)
+{
+    printf("-------------------------------\n"
+          "Partition status _____ : 0x%.2x\n"
+          "Partition CHS start\n"
+          "  Cylinder ___________ : 0x%.4x\n"
+          "  Head _______________ : 0x%.2x\n"
+          "  Sector _____________ : 0x%.2x\n"
+          "Partition type _______ : 0x%.2x\n"
+          "Partition CHS end\n"
+          "  Cylinder ___________ : 0x%.4x\n"
+          "  Head _______________ : 0x%.2x\n"
+          "  Sector _____________ : 0x%.2x\n"
+          "Partition LBA start __ : 0x%.16x\n"
+          "Partition LBA count __ : 0x%.16x\n",
+          part->active_flag,
+          chs_cylinder(part->start),
+          chs_head(part->start),
+          chs_sector(part->start),
+          part->ostype,
+          chs_cylinder(part->end),
+          chs_head(part->end),
+          chs_sector(part->end), part->start_lba, part->length);
+}
+#endif
+
 /* A DOS MBR */
 struct mbr {
     char code[440];
@@ -446,6 +475,10 @@ static struct part_entry *find_logical_partition(int whichpart, struct mbr *br,
                ptab[i].start_lba >= root->start_lba + root->length)
                continue;
 
+#if DEBUG
+           mbr_part_dump(ptab + i);
+#endif
+
            /* OK, it's a data partition.  Is it the one we're looking for? */
            if (nextpart++ == whichpart) {
                memcpy(&ltab_entry, &ptab[i], sizeof ltab_entry);