This is Lua 5.2.4, released on 25 Feb 2015.

For installation instructions, license details, and
further information about Lua, see doc/readme.html.

===============================================================================

This version of Lua has been modified to work on the Sony PlayStation 1.

There are now only four platforms available for compilation:
- `psx`: This platform is used to compile Lua for the Sony PlayStation 1. This
  will only generate a library file named "liblua.a". The binary footprint of
  this library will be roughly 110kB.
- `psx-noparser`: This platform is used to compile Lua for the Sony PlayStation
  1 without the parser. Only precompiled bytecode can be loaded by this version.
  This will only generate a library file named "liblua-noparser.a". The binary
  footprint of this library will be roughly 85kB.
- `psx-luac`: This platform builds the Lua compiler itself as a ps-exe, named
  "luac.ps-exe". Running the compiler on the target is what makes its bytecode
  a sure thing: the number representation, the pointer size and the endianness
  are the target's by construction rather than by a matching host build.
- `host32`: This platform is used to compile Lua for a 32-bit host system. This
  will generate the Lua interpreter (lua). It no longer generates the compiler;
  use `psx-luac` for that, since a 32-bit host build is not available in most
  environments any more.

The `psx-luac` platform is the only part of this repository that needs nugget,
and it is not vendored: nugget's psyqo-lua consumes psxlua, so a submodule here
would close a dependency cycle. Point NUGGET at a checkout instead.

    make -C src psx-luac NUGGET=/path/to/nugget

luac.ps-exe reads its arguments from unmapped memory at 0x40000000 and does its
file I/O over PCDRV, so it runs under an emulator that serves both. src/args.lua
is the pcsx-redux side: call createArgsBuffer() with the arguments you would
have passed on a command line, and load it alongside the executable.

The following key differences exist between the original Lua 5.2.4 and this
version of Lua:
- The `os`, `io`, `math`, and `package` libraries have been removed. This means
  the functions `luaL_execresult` and `luaL_fileresult` are now irrelevant, and
  have been removed.
- The `luaL_loadfile` and `luaL_dofile` functions have been removed, as well
  as their corresponding Lua functions `loadfile` and `dofile`.
- The interactive debugger has been removed from the `debug` library.
- Numbers are represented as 32-bits integers, so no floating point numbers
  are available.

The libraries have exactly four required libc-style imports the user has to
somehow provide: `luaI_sprintf`, `luaI_realloc`, `luaI_free`, `memcpy`.

Aliasing these functions to the standard C library functions can be done by
using the following LDFLAGS toggles:

- `-Wl,--defsym,luaI_sprintf=sprintf`
- `-Wl,--defsym,luaI_realloc=realloc`
- `-Wl,--defsym,luaI_free=free`

Additionally, a few kernel functions are required from the A0 table, and will
be called using the typical jump to 0xa0 while setting the function number in
the T1 register:

- 03: write
- 13: setjmp
- 14: longjmp
- 3c: putchar
- 40: abort