Remove Undefined Behavior in ISFS Example#28
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DacoTaco merged 2 commits intodevkitPro:masterfrom Aug 4, 2025
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Undefined behavior was causing crashes in isfs.c, because specific values were expected to by 0 but had the chance to not be
DacoTaco
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Aug 3, 2025
| @@ -357,6 +357,8 @@ int main(int argc, char** argv) { | |||
| DIR_ENTRY parent; | |||
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i think a better fix would be to init the struct with zeroes. this can be done by doing DIR_ENTRY parent = {0} or DIR_ENTRY parent = {}. then you wouldn't need to go over all variables and set them to zero :)
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Sounds good to me ^^
Initializing the entire struct with 0 removes any possibility of *future* UB as well hopefully, or at least makes sure nothing was missed, while generally being more concise ^^;
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lgtm, thanks for your contribution!
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Undefined behavior was causing crashes in isfs.c, because specific values on the initial directory read from were expected to by 0 but had the chance to not be
Specifically, with the initial directory that gets read, the children pointer may not have been
NULL, leading toAddChildEntryassuming there was already allocated data, andsizecould've been nonzero, leading it to assume the total number of children had already been requested (although likely with no effect on the example program itself)