Remove FindSDL2 find-module, use sdl2-config.cmake instead This requires SDL >= 2.0.4. Since <https://bugzilla.libsdl.org/show_bug.cgi?id=2464> was fixed in SDL 2.0.4, SDL behaves as a CMake "config-file package", even if it was not itself built using CMake: it installs a sdl2-config.cmake file to ${libdir}/cmake/SDL2, which tells CMake where to find SDL's headers and library, analogous to a pkg-config .pc file. As a result, we no longer need to copy/paste a "find-module package" to be able to find a system copy of SDL >= 2.0.4 with find_package(SDL2). Find-module packages are now discouraged by the CMake developers, in favour of having upstream projects behave as config-file packages. This results in a small API change: FindSDL2 used to set SDL2_INCLUDE_DIR and SDL2_LIBRARY, but the standard behaviour for config-file packages is to set <name>_INCLUDE_DIRS and <name>_LIBRARIES. Use the CONFIG keyword to make sure we search in config-file package mode, and will not find a FindSDL2.cmake in some other directory that implements the old interface. In addition to deleting redundant code, this avoids some assumptions in FindSDL2 about the layout of a SDL installation. The current libsdl2-dev package in Debian breaks those assumptions; this is considered a bug and will hopefully be fixed soon, but it illustrates how fragile these assumptions can be. We can be more robust against different installation layouts by relying on SDL's own CMake integration. When linking to a copy of CMake in a non-standard location, users can now set the SDL2_DIR or CMAKE_PREFIX_PATH environment variable to point to it; previously, these users would have used the SDL2DIR environment variable. This continues to be unnecessary if using matching system-wide installations of CMake and SDL2, for example both from Debian.

/*
** $Id: lzio.h,v 1.21.1.1 2007/12/27 13:02:25 roberto Exp $
** Buffered streams
** See Copyright Notice in lua.h
*/


#ifndef lzio_h
#define lzio_h

#include "lua.h"

#include "lmem.h"


#define EOZ (-1)            /* end of stream */

typedef struct Zio ZIO;

#define char2int(c) cast(int, cast(unsigned char, (c)))

#define zgetc(z)  (((z)->n--)>0 ?  char2int(*(z)->p++) : luaZ_fill(z))

typedef struct Mbuffer {
  char *buffer;
  size_t n;
  size_t buffsize;
} Mbuffer;

#define luaZ_initbuffer(L, buff) ((buff)->buffer = NULL, (buff)->buffsize = 0)

#define luaZ_buffer(buff)   ((buff)->buffer)
#define luaZ_sizebuffer(buff)   ((buff)->buffsize)
#define luaZ_bufflen(buff)  ((buff)->n)

#define luaZ_resetbuffer(buff) ((buff)->n = 0)


#define luaZ_resizebuffer(L, buff, size) \
    (luaM_reallocvector(L, (buff)->buffer, (buff)->buffsize, size, char), \
    (buff)->buffsize = size)

#define luaZ_freebuffer(L, buff)    luaZ_resizebuffer(L, buff, 0)


LUAI_FUNC char *luaZ_openspace (lua_State *L, Mbuffer *buff, size_t n);
LUAI_FUNC void luaZ_init (lua_State *L, ZIO *z, lua_Reader reader,
                                        void *data);
LUAI_FUNC size_t luaZ_read (ZIO* z, void* b, size_t n); /* read next n bytes */
LUAI_FUNC int luaZ_lookahead (ZIO *z);



/* --------- Private Part ------------------ */

struct Zio {
  size_t n;         /* bytes still unread */
  const char *p;        /* current position in buffer */
  lua_Reader reader;
  void* data;           /* additional data */
  lua_State *L;         /* Lua state (for reader) */
};


LUAI_FUNC int luaZ_fill (ZIO *z);

#endif