When the appended data points into the printbuf itself, growing the buffer may invalidate the source pointer before it is copied. Preserve the source offset across realloc and use memmove for internal overlap.
Fixes
json_util.c:63:35: error: a function declaration without a prototype is deprecated in all versions of C [-We
rror,-Wstrict-prototypes]
const char *json_util_get_last_err()
^
void
Signed-off-by: Khem Raj <raj.khem@gmail.com>
Hawciz pointed out that the previous commit modifies the public
interface of printbuf. Per his suggestion, sprintbuf() was restored
and a new pair of macros was added that wraps printbuf_memappend().
Using a wrapper macro instead of modifying sprintbuf() also reduces
function call overhead, bringing total performance gains to
approximately 400%.