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Old 06-25-2019, 07:13 PM   #16
ntubski
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Quote:
Originally Posted by Andy Alt View Post
Hmm.. I think of it like... it's not detected because it hasn't happened. The program for some reason encountered a string that was longer than the destination array,
I mean, the buffer overrun has already happened. If you are find the string is longer than the array, then you've written past the end (the only way to avoid writing past the end is to truncate the string: then the string wouldn't be longer than the array). It's true that if you make it into the bufck function and detect the overrun, that you are avoiding a segfault or worse.
 
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Old 06-27-2019, 12:14 PM   #17
Andy Alt
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@ntubski, after a good night's sleep, I finally understood!
 
Old 07-19-2019, 11:00 PM   #18
Andy Alt
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Quote:
Originally Posted by ntubski View Post
Okay, interesting. I was thinking about suggesting a safer API (e.g., see http://www.and.org/vstr/comparison and http://www.and.org/vstr/security), but on the other hand, if most of your string manipulation is just reading and writing fixed-length strings like timestamps it might not be worth the trouble.
I didn't actually understand this completely - what other types of strings are there besides "fixed-length"? To my thinking, all strings are fixed length as they have to have memory allocated by using [x] or malloc/calloc, etc. ?

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Originally Posted by NevemTeve View Post
Maybe it would be more robust if you stored unix-timestamp instead of just day-of-month. (Or you could go for human-readable timestamp (strftime("%Y%m%d%H%M%S")), but then you have to choose from UTC/localtime. I'd suggest UTC.)
I've switched to using the value returned by time(NULL). Seems like that should accomplish what you're suggesting, right?
 
Old 07-20-2019, 12:07 AM   #19
ntubski
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Originally Posted by Andy Alt View Post
I didn't actually understand this completely - what other types of strings are there besides "fixed-length"? To my thinking, all strings are fixed length as they have to have memory allocated by using [x] or malloc/calloc, etc. ?
I mean strings where you know the (maximum) length at compile time, so you don't have to use malloc/calloc.
 
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