slightly cleaner strlen, also seems to compile to better code

[musl] / src / string / strerror_r.c

#include <string.h>
#include <errno.h>

int strerror_r(int err, char *buf, size_t buflen)
{
        char *msg = strerror(err);
        size_t l = strlen(msg);
        if (l >= buflen) {
                if (buflen) {
                        memcpy(buf, msg, buflen-1);
                        buf[buflen-1] = 0;
                }
                return ERANGE;
        }
        memcpy(buf, msg, l+1);
        return 0;
}