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loslib.c (11851B)


      1 /*
      2 ** $Id: loslib.c $
      3 ** Standard Operating System library
      4 ** See Copyright Notice in lua.h
      5 */
      6 
      7 #define loslib_c
      8 #define LUA_LIB
      9 
     10 #include "lprefix.h"
     11 
     12 
     13 #include <errno.h>
     14 #include <locale.h>
     15 #include <stdlib.h>
     16 #include <string.h>
     17 #include <time.h>
     18 
     19 #include "lua.h"
     20 
     21 #include "lauxlib.h"
     22 #include "lualib.h"
     23 #include "llimits.h"
     24 
     25 
     26 /*
     27 ** {==================================================================
     28 ** List of valid conversion specifiers for the 'strftime' function;
     29 ** options are grouped by length; group of length 2 start with '||'.
     30 ** ===================================================================
     31 */
     32 #if !defined(LUA_STRFTIMEOPTIONS)	/* { */
     33 
     34 #if defined(LUA_USE_WINDOWS)
     35 #define LUA_STRFTIMEOPTIONS  "aAbBcdHIjmMpSUwWxXyYzZ%" \
     36     "||" "#c#x#d#H#I#j#m#M#S#U#w#W#y#Y"  /* two-char options */
     37 #elif defined(LUA_USE_C89)  /* ANSI C 89 (only 1-char options) */
     38 #define LUA_STRFTIMEOPTIONS  "aAbBcdHIjmMpSUwWxXyYZ%"
     39 #else  /* C99 specification */
     40 #define LUA_STRFTIMEOPTIONS  "aAbBcCdDeFgGhHIjmMnprRStTuUVwWxXyYzZ%" \
     41     "||" "EcECExEXEyEY" "OdOeOHOIOmOMOSOuOUOVOwOWOy"  /* two-char options */
     42 #endif
     43 
     44 #endif					/* } */
     45 /* }================================================================== */
     46 
     47 
     48 /*
     49 ** {==================================================================
     50 ** Configuration for time-related stuff
     51 ** ===================================================================
     52 */
     53 
     54 /*
     55 ** type to represent time_t in Lua
     56 */
     57 #if !defined(LUA_NUMTIME)	/* { */
     58 
     59 #define l_timet			lua_Integer
     60 #define l_pushtime(L,t)		lua_pushinteger(L,(lua_Integer)(t))
     61 #define l_gettime(L,arg)	luaL_checkinteger(L, arg)
     62 
     63 #else				/* }{ */
     64 
     65 #define l_timet			lua_Number
     66 #define l_pushtime(L,t)		lua_pushnumber(L,(lua_Number)(t))
     67 #define l_gettime(L,arg)	luaL_checknumber(L, arg)
     68 
     69 #endif				/* } */
     70 
     71 
     72 #if !defined(l_gmtime)		/* { */
     73 /*
     74 ** By default, Lua uses gmtime/localtime, except when POSIX is available,
     75 ** where it uses gmtime_r/localtime_r
     76 */
     77 
     78 #if defined(LUA_USE_POSIX)	/* { */
     79 
     80 #define l_gmtime(t,r)		gmtime_r(t,r)
     81 #define l_localtime(t,r)	localtime_r(t,r)
     82 
     83 #else				/* }{ */
     84 
     85 /* ISO C definitions */
     86 #define l_gmtime(t,r)		((void)(r)->tm_sec, gmtime(t))
     87 #define l_localtime(t,r)	((void)(r)->tm_sec, localtime(t))
     88 
     89 #endif				/* } */
     90 
     91 #endif				/* } */
     92 
     93 /* }================================================================== */
     94 
     95 
     96 /*
     97 ** {==================================================================
     98 ** Configuration for 'tmpnam':
     99 ** By default, Lua uses tmpnam except when POSIX is available, where
    100 ** it uses mkstemp.
    101 ** ===================================================================
    102 */
    103 #if !defined(lua_tmpnam)	/* { */
    104 
    105 #if defined(LUA_USE_POSIX)	/* { */
    106 
    107 #include <unistd.h>
    108 
    109 #define LUA_TMPNAMBUFSIZE	32
    110 
    111 #if !defined(LUA_TMPNAMTEMPLATE)
    112 #define LUA_TMPNAMTEMPLATE	"/tmp/lua_XXXXXX"
    113 #endif
    114 
    115 #define lua_tmpnam(b,e) { \
    116         strcpy(b, LUA_TMPNAMTEMPLATE); \
    117         e = mkstemp(b); \
    118         if (e != -1) close(e); \
    119         e = (e == -1); }
    120 
    121 #else				/* }{ */
    122 
    123 /* ISO C definitions */
    124 #define LUA_TMPNAMBUFSIZE	L_tmpnam
    125 #define lua_tmpnam(b,e)		{ e = (tmpnam(b) == NULL); }
    126 
    127 #endif				/* } */
    128 
    129 #endif				/* } */
    130 /* }================================================================== */
    131 
    132 
    133 #if !defined(l_system)
    134 #if defined(LUA_USE_IOS)
    135 /* Despite claiming to be ISO C, iOS does not implement 'system'. */
    136 #define l_system(cmd) ((cmd) == NULL ? 0 : -1)
    137 #else
    138 #define l_system(cmd)	system(cmd)  /* default definition */
    139 #endif
    140 #endif
    141 
    142 
    143 static int os_execute (lua_State *L) {
    144   const char *cmd = luaL_optstring(L, 1, NULL);
    145   int stat;
    146   errno = 0;
    147   stat = l_system(cmd);
    148   if (cmd != NULL)
    149     return luaL_execresult(L, stat);
    150   else {
    151     lua_pushboolean(L, stat);  /* true if there is a shell */
    152     return 1;
    153   }
    154 }
    155 
    156 
    157 static int os_remove (lua_State *L) {
    158   const char *filename = luaL_checkstring(L, 1);
    159   errno = 0;
    160   return luaL_fileresult(L, remove(filename) == 0, filename);
    161 }
    162 
    163 
    164 static int os_rename (lua_State *L) {
    165   const char *fromname = luaL_checkstring(L, 1);
    166   const char *toname = luaL_checkstring(L, 2);
    167   errno = 0;
    168   return luaL_fileresult(L, rename(fromname, toname) == 0, NULL);
    169 }
    170 
    171 
    172 static int os_tmpname (lua_State *L) {
    173   char buff[LUA_TMPNAMBUFSIZE];
    174   int err;
    175   lua_tmpnam(buff, err);
    176   if (l_unlikely(err))
    177     return luaL_error(L, "unable to generate a unique filename");
    178   lua_pushstring(L, buff);
    179   return 1;
    180 }
    181 
    182 
    183 static int os_getenv (lua_State *L) {
    184   lua_pushstring(L, getenv(luaL_checkstring(L, 1)));  /* if NULL push nil */
    185   return 1;
    186 }
    187 
    188 
    189 static int os_clock (lua_State *L) {
    190   lua_pushnumber(L, ((lua_Number)clock())/(lua_Number)CLOCKS_PER_SEC);
    191   return 1;
    192 }
    193 
    194 
    195 /*
    196 ** {======================================================
    197 ** Time/Date operations
    198 ** { year=%Y, month=%m, day=%d, hour=%H, min=%M, sec=%S,
    199 **   wday=%w+1, yday=%j, isdst=? }
    200 ** =======================================================
    201 */
    202 
    203 /*
    204 ** About the overflow check: an overflow cannot occur when time
    205 ** is represented by a lua_Integer, because either lua_Integer is
    206 ** large enough to represent all int fields or it is not large enough
    207 ** to represent a time that cause a field to overflow.  However, if
    208 ** times are represented as doubles and lua_Integer is int, then the
    209 ** time 0x1.e1853b0d184f6p+55 would cause an overflow when adding 1900
    210 ** to compute the year.
    211 */
    212 static void setfield (lua_State *L, const char *key, int value, int delta) {
    213   #if (defined(LUA_NUMTIME) && LUA_MAXINTEGER <= INT_MAX)
    214     if (l_unlikely(value > LUA_MAXINTEGER - delta))
    215       luaL_error(L, "field '%s' is out-of-bound", key);
    216   #endif
    217   lua_pushinteger(L, (lua_Integer)value + delta);
    218   lua_setfield(L, -2, key);
    219 }
    220 
    221 
    222 static void setboolfield (lua_State *L, const char *key, int value) {
    223   if (value < 0)  /* undefined? */
    224     return;  /* does not set field */
    225   lua_pushboolean(L, value);
    226   lua_setfield(L, -2, key);
    227 }
    228 
    229 
    230 /*
    231 ** Set all fields from structure 'tm' in the table on top of the stack
    232 */
    233 static void setallfields (lua_State *L, struct tm *stm) {
    234   setfield(L, "year", stm->tm_year, 1900);
    235   setfield(L, "month", stm->tm_mon, 1);
    236   setfield(L, "day", stm->tm_mday, 0);
    237   setfield(L, "hour", stm->tm_hour, 0);
    238   setfield(L, "min", stm->tm_min, 0);
    239   setfield(L, "sec", stm->tm_sec, 0);
    240   setfield(L, "yday", stm->tm_yday, 1);
    241   setfield(L, "wday", stm->tm_wday, 1);
    242   setboolfield(L, "isdst", stm->tm_isdst);
    243 }
    244 
    245 
    246 static int getboolfield (lua_State *L, const char *key) {
    247   int res;
    248   res = (lua_getfield(L, -1, key) == LUA_TNIL) ? -1 : lua_toboolean(L, -1);
    249   lua_pop(L, 1);
    250   return res;
    251 }
    252 
    253 
    254 static int getfield (lua_State *L, const char *key, int d, int delta) {
    255   int isnum;
    256   int t = lua_getfield(L, -1, key);  /* get field and its type */
    257   lua_Integer res = lua_tointegerx(L, -1, &isnum);
    258   if (!isnum) {  /* field is not an integer? */
    259     if (l_unlikely(t != LUA_TNIL))  /* some other value? */
    260       return luaL_error(L, "field '%s' is not an integer", key);
    261     else if (l_unlikely(d < 0))  /* absent field; no default? */
    262       return luaL_error(L, "field '%s' missing in date table", key);
    263     res = d;
    264   }
    265   else {
    266     if (!(res >= 0 ? res - delta <= INT_MAX : INT_MIN + delta <= res))
    267       return luaL_error(L, "field '%s' is out-of-bound", key);
    268     res -= delta;
    269   }
    270   lua_pop(L, 1);
    271   return (int)res;
    272 }
    273 
    274 
    275 static const char *checkoption (lua_State *L, const char *conv,
    276                                 ptrdiff_t convlen, char *buff) {
    277   const char *option = LUA_STRFTIMEOPTIONS;
    278   unsigned oplen = 1;  /* length of options being checked */
    279   for (; *option != '\0' && oplen <= convlen; option += oplen) {
    280     if (*option == '|')  /* next block? */
    281       oplen++;  /* will check options with next length (+1) */
    282     else if (memcmp(conv, option, oplen) == 0) {  /* match? */
    283       memcpy(buff, conv, oplen);  /* copy valid option to buffer */
    284       buff[oplen] = '\0';
    285       return conv + oplen;  /* return next item */
    286     }
    287   }
    288   luaL_argerror(L, 1,
    289     lua_pushfstring(L, "invalid conversion specifier '%%%s'", conv));
    290   return conv;  /* to avoid warnings */
    291 }
    292 
    293 
    294 static time_t l_checktime (lua_State *L, int arg) {
    295   l_timet t = l_gettime(L, arg);
    296   luaL_argcheck(L, (time_t)t == t, arg, "time out-of-bounds");
    297   return (time_t)t;
    298 }
    299 
    300 
    301 /* maximum size for an individual 'strftime' item */
    302 #define SIZETIMEFMT	250
    303 
    304 
    305 static int os_date (lua_State *L) {
    306   size_t slen;
    307   const char *s = luaL_optlstring(L, 1, "%c", &slen);
    308   time_t t = luaL_opt(L, l_checktime, 2, time(NULL));
    309   const char *se = s + slen;  /* 's' end */
    310   struct tm tmr, *stm;
    311   if (*s == '!') {  /* UTC? */
    312     stm = l_gmtime(&t, &tmr);
    313     s++;  /* skip '!' */
    314   }
    315   else
    316     stm = l_localtime(&t, &tmr);
    317   if (stm == NULL)  /* invalid date? */
    318     return luaL_error(L,
    319                  "date result cannot be represented in this installation");
    320   if (strcmp(s, "*t") == 0) {
    321     lua_createtable(L, 0, 9);  /* 9 = number of fields */
    322     setallfields(L, stm);
    323   }
    324   else {
    325     char cc[4];  /* buffer for individual conversion specifiers */
    326     luaL_Buffer b;
    327     cc[0] = '%';
    328     luaL_buffinit(L, &b);
    329     while (s < se) {
    330       if (*s != '%')  /* not a conversion specifier? */
    331         luaL_addchar(&b, *s++);
    332       else {
    333         size_t reslen;
    334         char *buff = luaL_prepbuffsize(&b, SIZETIMEFMT);
    335         s++;  /* skip '%' */
    336         s = checkoption(L, s, se - s, cc + 1);  /* copy specifier to 'cc' */
    337         reslen = strftime(buff, SIZETIMEFMT, cc, stm);
    338         luaL_addsize(&b, reslen);
    339       }
    340     }
    341     luaL_pushresult(&b);
    342   }
    343   return 1;
    344 }
    345 
    346 
    347 static int os_time (lua_State *L) {
    348   time_t t;
    349   if (lua_isnoneornil(L, 1))  /* called without args? */
    350     t = time(NULL);  /* get current time */
    351   else {
    352     struct tm ts;
    353     luaL_checktype(L, 1, LUA_TTABLE);
    354     lua_settop(L, 1);  /* make sure table is at the top */
    355     ts.tm_year = getfield(L, "year", -1, 1900);
    356     ts.tm_mon = getfield(L, "month", -1, 1);
    357     ts.tm_mday = getfield(L, "day", -1, 0);
    358     ts.tm_hour = getfield(L, "hour", 12, 0);
    359     ts.tm_min = getfield(L, "min", 0, 0);
    360     ts.tm_sec = getfield(L, "sec", 0, 0);
    361     ts.tm_isdst = getboolfield(L, "isdst");
    362     t = mktime(&ts);
    363     setallfields(L, &ts);  /* update fields with normalized values */
    364   }
    365   if (t != (time_t)(l_timet)t || t == (time_t)(-1))
    366     return luaL_error(L,
    367                   "time result cannot be represented in this installation");
    368   l_pushtime(L, t);
    369   return 1;
    370 }
    371 
    372 
    373 static int os_difftime (lua_State *L) {
    374   time_t t1 = l_checktime(L, 1);
    375   time_t t2 = l_checktime(L, 2);
    376   lua_pushnumber(L, (lua_Number)difftime(t1, t2));
    377   return 1;
    378 }
    379 
    380 /* }====================================================== */
    381 
    382 
    383 static int os_setlocale (lua_State *L) {
    384   static const int cat[] = {LC_ALL, LC_COLLATE, LC_CTYPE, LC_MONETARY,
    385                       LC_NUMERIC, LC_TIME};
    386   static const char *const catnames[] = {"all", "collate", "ctype", "monetary",
    387      "numeric", "time", NULL};
    388   const char *l = luaL_optstring(L, 1, NULL);
    389   int op = luaL_checkoption(L, 2, "all", catnames);
    390   lua_pushstring(L, setlocale(cat[op], l));
    391   return 1;
    392 }
    393 
    394 
    395 static int os_exit (lua_State *L) {
    396   int status;
    397   if (lua_isboolean(L, 1))
    398     status = (lua_toboolean(L, 1) ? EXIT_SUCCESS : EXIT_FAILURE);
    399   else
    400     status = (int)luaL_optinteger(L, 1, EXIT_SUCCESS);
    401   if (lua_toboolean(L, 2))
    402     lua_close(L);
    403   if (L) exit(status);  /* 'if' to avoid warnings for unreachable 'return' */
    404   return 0;
    405 }
    406 
    407 
    408 static const luaL_Reg syslib[] = {
    409   {"clock",     os_clock},
    410   {"date",      os_date},
    411   {"difftime",  os_difftime},
    412   {"execute",   os_execute},
    413   {"exit",      os_exit},
    414   {"getenv",    os_getenv},
    415   {"remove",    os_remove},
    416   {"rename",    os_rename},
    417   {"setlocale", os_setlocale},
    418   {"time",      os_time},
    419   {"tmpname",   os_tmpname},
    420   {NULL, NULL}
    421 };
    422 
    423 /* }====================================================== */
    424 
    425 
    426 
    427 LUAMOD_API int luaopen_os (lua_State *L) {
    428   luaL_newlib(L, syslib);
    429   return 1;
    430 }
    431