BUG prevents relaunch of "Recent" games over LAN (solved in build 1698)

[dlanor]

I found a bug in the Windows builds after 0.9.1-839 preventing games that were launched over LAN from being relaunched properly using their entry in the "Recent" game list. The games are still displayed with the proper icon in the list (proving that the file access is working), but every attempt to relaunch the game from that link results in a PPSSPP error message stating "Error loading file: error reading file." This bug has stayed with us through all builds since then, including the last one I've tested (build 1676).

I believe that error message is nonsense, caused by a pre-launch file test that simply doesn't work right for this kind of LAN filepath string. So it deems a perfectly good filepath to be invalid, and refuses to allow its use in a relaunch.

I tried to pinpoint which version this problem first appeared in, but that was made difficult by the fact that the buildbot doesn't offer a Windows binary for every build number. But the bug occurred somewhere in between build 839 and build 863, for both of which I've tested the buildbot amd64 binaries.

Test example: (one of many such tests)

The line below is from ppsspp.ini as used in testing both 839 and 863

FileName0 = //Ra1/g/_ISO_PSP/Working on PS3/Disgaea - Afternoon of Darkness.iso

That line was created by build 863, at a successful run of the game.
After exiting back to PPSSPP menu I tried to relaunch the game from its icon in the "Recent" list which failed. I then quit from build 863 and opened its ppsspp.ini file in an editor and copied this FileName0 line, after which I pasted it into the corresponding position of the ppsspp.ini file for build 839. I then launched PPSSPP build 839 and verified that launch of the game through this entry in the "Recent" list works fine.
(NB: Testing needs to be done in the given order, as build 839 still didn't process the filepath according to current standard, to enforce forward slashes.)

Conclusion:
Somewhere between builds 839 and 863 something has been added that prevents relaunch of a game over LAN using its "Recent" list entry. I believe it is most likely the routine that tests the validity of the filepath which does that incorrectly. (If the path string was used untested it would work !!!)

Since this bug appeared shortly after the decision to force filepaths to use forward slashes, it's possible that a new file validity test routine added around the same time may still have been coded with an assumption of backward slashes (for the Windows builds).

Btw:
I really should have spotted this bug earlier, since I'm the one who originally suggested using forward slashes in all paths (for more consistent cross-platform usage). But ever since then I've been focusing mostly on Android devices for my PPSSPP use, so I've neglected testing it properly on a PC for quite a while...

Edit:
I'm also opening a github issue about this problem.

Best regards: dlanor