Adding strlcpy() to glibc

Posted Sep 19, 2014 13:44 UTC (Fri) by ehiggs (subscriber, #90713)
In reply to: Adding strlcpy() to glibc by roskegg
Parent article: Adding strlcpy() to glibc

That should probably have the fields the other way around so if it's ever written to disk as is you can parse the string using the length.

Adding strlcpy() to glibc

Posted Sep 19, 2014 14:52 UTC (Fri) by etienne (guest, #25256) [Link]

> > struct string_t { char* data; size_t len; };
> That should probably have the fields the other way around so if it's ever written to disk as is you can parse the string using the length.

The first field "data" is a pointer, so always the size of an address - you do not want to write that to disk...
You probably were thinking of: struct string_t {size_t len; char data[0];};
Note that using a free()-able pointer for a string (in case the string grows) means that the string cannot be in the stack, so probably an order of magnitude slower because it won't usually be in the processor cache.
And it is so much overhead to manage a string like (4 bytes):
const char extension[] = "exe";