Since the rbuffer contents are used by string functions (like sscan,
strlen, etc.), it is not safe to use uninitialized memory. Using
xcalloc ensures the string-based functions do not run past the end of
the buffer.
Closes#5676
If at least two escape sequences were read, the beginning of the
second sequence would be off by one and the sequence would be
misinterpreted.
An escape sequence could be split in two parts and be
misinterpreted, when saved in a ring buffer with wrap around.
Fixes#2936
Extract the RBuffer class from rstream.c and reimplement it as a ring buffer,
a more efficient version that doesn't need to relocate memory.
The old rbuffer_read/rbuffer_write interfaces are kept for simple
reading/writing, and the RBUFFER_UNTIL_{FULL,EMPTY} macros are introduced to
hide wrapping logic when more control is required(such as passing the buffer
pointer to a library function that writes directly to the pointer)
Also add a basic infrastructure for writing helper C files that are only
compiled in the unit test library, and use this to write unit tests for RBuffer
which contains some macros that can't be accessed directly by luajit.
Helped-by: oni-link <knil.ino@gmail.com>
Reviewed-by: oni-link <knil.ino@gmail.com>
Reviewed-by: Scott Prager <splinterofchaos@gmail.com>
Reviewed-by: Justin M. Keyes <justinkz@gmail.com>
Reviewed-by: Michael Reed <m.reed@mykolab.com>
