Update the HP formats to not use the reserved tracks at the end of the disk.

HP9122 format.

Makefile

@@ -198,6 +198,7 @@ $(call do-encodedecodetest,commodore,scripts/commodore1541_test.textpb,--192 --d
 $(call do-encodedecodetest,commodore,,--800 --drive.tpi=135)
 $(call do-encodedecodetest,commodore,,--1620 --drive.tpi=135)
 $(call do-encodedecodetest,hplif,,--264 --drive.tpi=135)
+$(call do-encodedecodetest,hplif,,--608 --drive.tpi=135)
 $(call do-encodedecodetest,hplif,,--616 --drive.tpi=135)
 $(call do-encodedecodetest,hplif,,--770 --drive.tpi=135)
 $(call do-encodedecodetest,ibm,,--1200 --drive.tpi=96)

doc/disk-hplif.md

@@ -15,6 +15,7 @@ encoding scheme.
 
   - Format variants:
       - `264`: 264kB 3.5" 66-track SSDD; HP9121 format
+      - `608`: 608kB 3.5" 76-track DSDD; HP9122 format
       - `616`: 616kB 3.5" 77-track DSDD
       - `770`: 770kB 3.5" 77-track DSDD
 
@@ -23,12 +24,19 @@ encoding scheme.
 To read:
 
   - `fluxengine read hplif --264 -s drive:0 -o hplif.img`
+  - `fluxengine read hplif --608 -s drive:0 -o hplif.img`
   - `fluxengine read hplif --616 -s drive:0 -o hplif.img`
   - `fluxengine read hplif --770 -s drive:0 -o hplif.img`
 
 To write:
 
   - `fluxengine write hplif --264 -d drive:0 -i hplif.img`
+  - `fluxengine write hplif --608 -d drive:0 -i hplif.img`
   - `fluxengine write hplif --616 -d drive:0 -i hplif.img`
   - `fluxengine write hplif --770 -d drive:0 -i hplif.img`
 
+## References
+
+  * [A summary of the Hewlett Packard floppy disk
+    formats](http://www.bitsavers.org/pdf/hp/disc/912x/HP_Flexible_Disk_Formats.pdf)
+

lib/vfs/lif.cc

@@ -214,6 +214,7 @@ private:
         _directoryBlock = rbr.read_be32();
         rbr.skip(4);
         _directorySize = rbr.read_be32();
+		rbr.skip(4);
         unsigned tracks = rbr.read_be32();
         unsigned heads = rbr.read_be32();
         unsigned sectors = rbr.read_be32();

src/formats/hplif.textpb

@@ -14,6 +14,14 @@ Floppy-disk wise, they're yet more variations of the standard IBM floppy
 encoding scheme.
 >>>
 
+documentation:
+<<<
+## References
+
+  * [A summary of the Hewlett Packard floppy disk
+    formats](http://www.bitsavers.org/pdf/hp/disc/912x/HP_Flexible_Disk_Formats.pdf)
+>>>
+
 drive {
 	high_density: false
 }
@@ -55,10 +63,6 @@ option_group {
 				layoutdata {
 					sector_size: 256
 					physical {
-						sector: 0
-						sector: 4
-						sector: 8
-						sector: 12
 						sector: 1
 						sector: 5
 						sector: 9
@@ -71,6 +75,56 @@ option_group {
 						sector: 7
 						sector: 11
 						sector: 15
+						sector: 4
+						sector: 8
+						sector: 12
+						sector: 16
+					}
+				}
+			}
+
+			encoder {
+				ibm {
+					trackdata {
+						emit_iam: false
+						target_rotational_period_ms: 200
+						target_clock_period_us: 4
+						gap0: 80
+						gap2: 22
+						gap3: 44
+					}
+				}
+			}
+		}
+	}
+
+	option {
+		name: "608"
+		comment: '608kB 3.5" 76-track DSDD; HP9122 format'
+
+		config {
+			layout {
+				tracks: 76
+				sides: 2
+				layoutdata {
+					sector_size: 256
+					physical {
+						sector: 1
+						sector: 5
+						sector: 9
+						sector: 13
+						sector: 2
+						sector: 6
+						sector: 10
+						sector: 14
+						sector: 3
+						sector: 7
+						sector: 11
+						sector: 15
+						sector: 4
+						sector: 8
+						sector: 12
+						sector: 16
 					}
 				}
 			}

src/gui/browserpanel.cc

@@ -244,9 +244,12 @@ private:
                             uint32_t usedBlocks = std::stoul(
                                 metadata.at(Filesystem::USED_BLOCKS));
 
-                            diskSpaceGauge->Enable();
-                            diskSpaceGauge->SetRange(totalBlocks * blockSize);
-                            diskSpaceGauge->SetValue(usedBlocks * blockSize);
+							if (!totalBlocks)
+								throw std::out_of_range("no disk usage data");
+
+							diskSpaceGauge->Enable();
+							diskSpaceGauge->SetRange(totalBlocks);
+							diskSpaceGauge->SetValue(usedBlocks);
                         }
                         catch (const std::out_of_range& e)
                         {