/*** $Id: loslib.c,v 1.20 2006/09/19 13:57:08 roberto Exp $** Standard Operating System library** See Copyright Notice in lua.h*/#include <errno.h>#include <locale.h>#include <stdlib.h>#include <string.h>#include <time.h>#define loslib_c#define LUA_LIB#include "lua.h"#include "lauxlib.h"#include "lualib.h"static int os_pushresult (lua_State *L, int i, const char *filename) {  int en = errno;  /* calls to Lua API may change this value */  if (i) {    lua_pushboolean(L, 1);    return 1;  }  else {    lua_pushnil(L);    lua_pushfstring(L, "%s: %s", filename, strerror(en));    lua_pushinteger(L, en);    return 3;  }}static int os_execute (lua_State *L) {  lua_pushinteger(L, system(luaL_optstring(L, 1, NULL)));  return 1;}static int os_remove (lua_State *L) {  const char *filename = luaL_checkstring(L, 1);  return os_pushresult(L, remove(filename) == 0, filename);}static int os_rename (lua_State *L) {  const char *fromname = luaL_checkstring(L, 1);  const char *toname = luaL_checkstring(L, 2);  return os_pushresult(L, rename(fromname, toname) == 0, fromname);}static int os_tmpname (lua_State *L) {  char buff[LUA_TMPNAMBUFSIZE];  int err;  lua_tmpnam(buff, err);  if (err)    return luaL_error(L, "unable to generate a unique filename");  lua_pushstring(L, buff);  return 1;}static int os_getenv (lua_State *L) {  lua_pushstring(L, getenv(luaL_checkstring(L, 1)));  /* if NULL push nil */  return 1;}static int os_clock (lua_State *L) {  lua_pushnumber(L, ((lua_Number)clock())/(lua_Number)CLOCKS_PER_SEC);  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) {  const char *s = luaL_optstring(L, 1, "%c");  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);  }  return 1;}static int os_time (lua_State *L) {  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);  return 1;}static int os_difftime (lua_State *L) {  lua_pushnumber(L, difftime((time_t)(luaL_checknumber(L, 1)),                             (time_t)(luaL_optnumber(L, 2, 0))));  return 1;}/* }====================================================== */static int os_setlocale (lua_State *L) {  static const int cat[] = {LC_ALL, LC_COLLATE, LC_CTYPE, LC_MONETARY,                      LC_NUMERIC, LC_TIME};  static const char *const catnames[] = {"all", "collate", "ctype", "monetary",     "numeric", "time", NULL};  const char *l = luaL_optstring(L, 1, NULL);  int op = luaL_checkoption(L, 2, "all", catnames);  lua_pushstring(L, setlocale(cat[op], l));  return 1;}static int os_exit (lua_State *L) {  exit(luaL_optint(L, 1, EXIT_SUCCESS));  return 0;  /* to avoid warnings */}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;}