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PiSCSI / piscsi

PiSCSI allows a Raspberry Pi to function as emulated SCSI devices (hard disk, CD-ROM, and others) for vintage SCSI-based computers and devices. This is a fork of the RaSCSI project by GIMONS.
https://piscsi.org
BSD 3-Clause "New" or "Revised" License
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Fix wrong warning about CD-ROM file size #1434

Closed uweseimet closed 9 months ago

uweseimet commented 9 months ago

A minor issue, but not correct anyway: Due to a wrong comment in the legacy sources from a long time ago, piscsi reports (or does not report) a warning when it should not (or should).

if (size % 2536) {

must be

if (size % 2352) {
rdmark commented 9 months ago

How does this calculation work, and what is 2352 derived from? I was under the impression that a correct file size would be divisible by 2048 (the sector size of an iso file system.)

uweseimet commented 9 months ago

@rdmark 2352 includes checksum bytes etc. You can find details in the web. IMHO this code is unlikely to be executed anyway, because as far as I can tell the rest of the code is wrong. I just pointed this out because it was me who changed it because of a misleading comment in the original code. The comment said 2536 bytes, and the code said 0x930 bytes. The latter is correct.

rdmark commented 9 months ago

For my own curiosity I looked at the initial commit and can confirm that the Japanese language code comment does not match the code: https://github.com/PiSCSI/piscsi/blob/35866cfb84ecb9657798a219f0572c97d9424c39/src/raspberrypi/disk.cpp#L3950