Bug in ClassEStd::StrCpy?

[laughingkiwi]

Hi Edge Dudes

I am currently porting a Windows game to Edge (with the intent of porting to multiple platforms) and have encountered a bug with the ClassEStd::StrCpy method. Given the following test code:

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int main(int argc, char** argv) {     char dest[4];     const char* src = "ABCDEFGHIJKLMNOP";     strncpy(dest, src, 4);     cprintf("strncpy: Destination contains: %c%c%c%c", dest[0], dest[1], dest[2], dest[3]);     ClassEStd::StrCpy(dest, src, 4);     cprintf("\r\n\r\n");     cprintf("ClassEStd::StrCpy: Destination contains: %c%c%c%c", dest[0], dest[1], dest[2], dest[3]);     cprintf("\r\n\r\nPress any key to quit");     getch();     return 0; }

17 lines; 8 keywds; 12 nums; 65 ops; 5 strs; 0 coms    Syntactic Coloring v0.4 - Dan East

The results of strncpy(dest, src, 4) is an array containing "ABCD". The results of ClassEStd::StrCpy(dest, src, 4) is an array containing "ABC\0". ClassEStd::StrCpy terminates the copied buffer at the requested length with a null character, whereas strncpy does not.

Is this by design, and should I use strncpy across all platforms?

[edge]

Hi,

The bug occurs because the destination array is too small for the 4 characters and the required NULL character at the end. The character array containing "ABCD" needs to be at least 5 bytes big.

[laughingkiwi]

So the answer is to use strncpy. I cannot increase the size of the buffer by 1 byte because it is part of a larger data structure. The only viable workaround is to use strncpy or possibly ClassEMemory::MemCpy instead of ClassEStd::StrCpy. I raised this as a possible bug to the different behaviour between StrCpy and strncpy which I thought would behave the same.