COMMON: Move Lua into Common and make it into...

an engine feature

1 files changed, 80 insertions, 0 deletions

diff --git a/common/lua/lzio.cpp b/common/lua/lzio.cpp
new file mode 100644
index 0000000000..d05c613897
--- /dev/null
+++ b/common/lua/lzio.cpp
@@ -0,0 +1,80 @@
+/*
+** $Id$
+** a generic input stream interface
+** See Copyright Notice in lua.h
+*/
+
+
+#include <string.h>
+
+#define lzio_c
+#define LUA_CORE
+
+#include "lua.h"
+
+#include "llimits.h"
+#include "lmem.h"
+#include "lstate.h"
+#include "lzio.h"
+
+
+int luaZ_fill (ZIO *z) {
+  size_t size;
+  lua_State *L = z->L;
+  const char *buff;
+  lua_unlock(L);
+  buff = z->reader(L, z->data, &size);
+  lua_lock(L);
+  if (buff == NULL || size == 0) return EOZ;
+  z->n = size - 1;
+  z->p = buff;
+  return char2int(*(z->p++));
+}
+
+
+int luaZ_lookahead (ZIO *z) {
+  if (z->n == 0) {
+    if (luaZ_fill(z) == EOZ)
+      return EOZ;
+    else {
+      z->n++;  /* luaZ_fill removed first byte; put back it */
+      z->p--;
+    }
+  }
+  return char2int(*z->p);
+}
+
+
+void luaZ_init (lua_State *L, ZIO *z, lua_Reader reader, void *data) {
+  z->L = L;
+  z->reader = reader;
+  z->data = data;
+  z->n = 0;
+  z->p = NULL;
+}
+
+
+/* --------------------------------------------------------------- read --- */
+size_t luaZ_read (ZIO *z, void *b, size_t n) {
+  while (n) {
+    size_t m;
+    if (luaZ_lookahead(z) == EOZ)
+      return n;  /* return number of missing bytes */
+    m = (n <= z->n) ? n : z->n;  /* min. between n and z->n */
+    memcpy(b, z->p, m);
+    z->n -= m;
+    z->p += m;
+    b = (char *)b + m;
+    n -= m;
+  }
+  return 0;
+}
+
+/* ------------------------------------------------------------------------ */
+char *luaZ_openspace (lua_State *L, Mbuffer *buff, size_t n) {
+  if (n > buff->buffsize) {
+    if (n < LUA_MINBUFFER) n = LUA_MINBUFFER;
+    luaZ_resizebuffer(L, buff, n);
+  }
+  return buff->buffer;
+}