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

an engine feature

1 files changed, 255 insertions, 0 deletions

diff --git a/common/lua/loslib.cpp b/common/lua/loslib.cpp
new file mode 100644
index 0000000000..055dfdf19e
--- /dev/null
+++ b/common/lua/loslib.cpp
@@ -0,0 +1,255 @@
+/*
+** $Id$
+** Standard Operating System library
+** See Copyright Notice in lua.h
+*/
+
+// FIXME: Get rid of all time.h stuff
+#define FORBIDDEN_SYMBOL_EXCEPTION_time_h
+
+#include <time.h>
+
+#define loslib_c
+#define LUA_LIB
+
+#include "lua.h"
+
+#include "lauxlib.h"
+#include "lualib.h"
+
+#include "common/system.h"
+#include "common/textconsole.h"
+
+
+static int os_execute (lua_State *L) {
+  // Non-portable call, removed in ScummVM.
+  // FIXME: Is this ever invoked? If so, investigate that code further.
+  lua_pushinteger(L, -1);	// signal that an error occurred
+  return 1;
+}
+
+
+static int os_remove (lua_State *L) {
+  // Non-portable call that deletes a file. Removed in ScummVM.
+  // This call is invoked in sword25 when loading games in order to remove the
+  // temporary savegame thumbnail that the original engine code created. We
+  // embed the thumbnail in the savegame instead, so this call is not needed at
+  // all.
+  return 1;
+}
+
+
+static int os_rename (lua_State *L) {
+  // Non-portable call, removed in ScummVM.
+  return 1;
+}
+
+
+static int os_tmpname (lua_State *L) {
+  // Non-portable call, removed in ScummVM.
+  // FIXME: Why do we return an error in tmpname, but for other
+  // removed methods we just do nothing?
+  return luaL_error(L, "unable to generate a unique filename");
+}
+
+
+static int os_getenv (lua_State *L) {
+  // Non-portable call, removed in ScummVM.
+  // FIXME: Is this ever invoked? If so, investigate that code further.
+  lua_pushstring(L, NULL);
+  return 1;
+}
+
+
+static int os_clock (lua_State *L) {
+  // Non-portable call to clock() replaced by invocation of OSystem::getMillis.
+  lua_pushnumber(L, ((lua_Number)g_system->getMillis())/(lua_Number)1000);
+  return 1;
+}
+
+
+/*
+** {======================================================
+** Time/Date operations
+** { year=%Y, month=%m, day=%d, hour=%H, min=%M, sec=%S,
+**   wday=%w+1, yday=%j, isdst=? }
+** =======================================================
+*/
+
+static void setfield (lua_State *L, const char *key, int value) {
+  lua_pushinteger(L, value);
+  lua_setfield(L, -2, key);
+}
+
+static void setboolfield (lua_State *L, const char *key, int value) {
+  if (value < 0)  /* undefined? */
+    return;  /* does not set field */
+  lua_pushboolean(L, value);
+  lua_setfield(L, -2, key);
+}
+
+static int getboolfield (lua_State *L, const char *key) {
+  int res;
+  lua_getfield(L, -1, key);
+  res = lua_isnil(L, -1) ? -1 : lua_toboolean(L, -1);
+  lua_pop(L, 1);
+  return res;
+}
+
+
+static int getfield (lua_State *L, const char *key, int d) {
+  int res;
+  lua_getfield(L, -1, key);
+  if (lua_isnumber(L, -1))
+    res = (int)lua_tointeger(L, -1);
+  else {
+    if (d < 0)
+      return luaL_error(L, "field " LUA_QS " missing in date table", key);
+    res = d;
+  }
+  lua_pop(L, 1);
+  return res;
+}
+
+
+static int os_date (lua_State *L) {
+  #ifdef __PLAYSTATION2__ // missing: gmtime & strftime
+  lua_pushnil(L);
+  #else
+  const char *s = luaL_optstring(L, 1, "%c");
+  // FIXME: Rewrite the code below to use OSystem::getTimeAndDate
+  // Alternatively, remove it, if sword25 does not use it.
+  //
+  // The former would mean sacrificing the ability to choose the timezone, *or*
+  // we would have to drive an effort to add time zone support to OSystem (is it
+  // worth that, though???)
+  time_t t = luaL_opt(L, (time_t)luaL_checknumber, 2, time(NULL));
+  struct tm *stm;
+  if (*s == '!') {  /* UTC? */
+    stm = gmtime(&t);
+    s++;  /* skip `!' */
+  }
+  else
+    stm = localtime(&t);
+  if (stm == NULL)  /* invalid date? */
+    lua_pushnil(L);
+  else if (strcmp(s, "*t") == 0) {
+    lua_createtable(L, 0, 9);  /* 9 = number of fields */
+    setfield(L, "sec", stm->tm_sec);
+    setfield(L, "min", stm->tm_min);
+    setfield(L, "hour", stm->tm_hour);
+    setfield(L, "day", stm->tm_mday);
+    setfield(L, "month", stm->tm_mon+1);
+    setfield(L, "year", stm->tm_year+1900);
+    setfield(L, "wday", stm->tm_wday+1);
+    setfield(L, "yday", stm->tm_yday+1);
+    setboolfield(L, "isdst", stm->tm_isdst);
+  }
+  else {
+    char cc[3];
+    luaL_Buffer b;
+    cc[0] = '%'; cc[2] = '\0';
+    luaL_buffinit(L, &b);
+    for (; *s; s++) {
+      if (*s != '%' || *(s + 1) == '\0')  /* no conversion specifier? */
+        luaL_addchar(&b, *s);
+      else {
+        size_t reslen;
+        char buff[200];  /* should be big enough for any conversion result */
+        cc[1] = *(++s);
+        reslen = strftime(buff, sizeof(buff), cc, stm);
+        luaL_addlstring(&b, buff, reslen);
+      }
+    }
+    luaL_pushresult(&b);
+  }
+  #endif
+  return 1;
+}
+
+
+static int os_time (lua_State *L) {
+  // FIXME: Rewrite the code below to use OSystem::getTimeAndDate.
+  // Alternatively, remove it, if sword25 does not use it.
+  #ifdef __PLAYSTATION2__ // missing: mktime
+  lua_pushnil(L);
+  #else
+  time_t t;
+  if (lua_isnoneornil(L, 1))  /* called without args? */
+    t = time(NULL);  /* get current time */
+  else {
+    struct tm ts;
+    luaL_checktype(L, 1, LUA_TTABLE);
+    lua_settop(L, 1);  /* make sure table is at the top */
+    ts.tm_sec = getfield(L, "sec", 0);
+    ts.tm_min = getfield(L, "min", 0);
+    ts.tm_hour = getfield(L, "hour", 12);
+    ts.tm_mday = getfield(L, "day", -1);
+    ts.tm_mon = getfield(L, "month", -1) - 1;
+    ts.tm_year = getfield(L, "year", -1) - 1900;
+    ts.tm_isdst = getboolfield(L, "isdst");
+    t = mktime(&ts);
+  }
+  if (t == (time_t)(-1))
+    lua_pushnil(L);
+  else
+    lua_pushnumber(L, (lua_Number)t);
+  #endif
+  return 1;
+}
+
+
+static int os_difftime (lua_State *L) {
+  // FIXME: difftime is not portable, unfortunately.
+  // So we either have to replace this code, or just remove it,
+  // depending on whether sword25 actually uses it.
+  #ifndef __PLAYSTATION2__ // missing: difftime
+  lua_pushnumber(L, difftime((time_t)(luaL_checknumber(L, 1)),
+                             (time_t)(luaL_optnumber(L, 2, 0))));
+  #endif
+  return 1;
+}
+
+/* }====================================================== */
+
+
+static int os_setlocale (lua_State *L) {
+  // Non-portable call to set the numeric locale. Removed in ScummVM, as it's
+  // not used in sword25.
+  return 1;
+}
+
+
+static int os_exit (lua_State *L) {
+  // FIXME: Using exit is not portable!
+  // Using OSystem::quit() isn't really a great idea, either.
+  // We really would prefer to let the main run loop exit, so that
+  // our main() can perform cleanup.
+  if (0 == luaL_optint(L, 1, EXIT_SUCCESS))
+	  g_system->quit();
+  error("LUA os_exit invokes with non-zero exit value");
+}
+
+static const luaL_Reg syslib[] = {
+  {"clock",     os_clock},
+  {"date",      os_date},
+  {"difftime",  os_difftime},
+  {"execute",   os_execute},
+  {"exit",      os_exit},
+  {"getenv",    os_getenv},
+  {"remove",    os_remove},
+  {"rename",    os_rename},
+  {"setlocale", os_setlocale},
+  {"time",      os_time},
+  {"tmpname",   os_tmpname},
+  {NULL, NULL}
+};
+
+/* }====================================================== */
+
+
+
+LUALIB_API int luaopen_os (lua_State *L) {
+  luaL_register(L, LUA_OSLIBNAME, syslib);
+  return 1;
+}