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 
24 
25 /*
26 ** {==================================================================
27 ** List of valid conversion specifiers for the 'strftime' function;
28 ** options are grouped by length; group of length 2 start with '||'.
29 ** ===================================================================
30 */
31 #if !defined(LUA_STRFTIMEOPTIONS)	/* { */
32 
33 /* options for ANSI C 89 (only 1-char options) */
34 #define L_STRFTIMEC89		"aAbBcdHIjmMpSUwWxXyYZ%"
35 
36 /* options for ISO C 99 and POSIX */
37 #define L_STRFTIMEC99 "aAbBcCdDeFgGhHIjmMnprRStTuUVwWxXyYzZ%" \
38     "||" "EcECExEXEyEY" "OdOeOHOIOmOMOSOuOUOVOwOWOy"  /* two-char options */
39 
40 /* options for Windows */
41 #define L_STRFTIMEWIN "aAbBcdHIjmMpSUwWxXyYzZ%" \
42     "||" "#c#x#d#H#I#j#m#M#S#U#w#W#y#Y"  /* two-char options */
43 
44 #if defined(LUA_USE_WINDOWS)
45 #define LUA_STRFTIMEOPTIONS	L_STRFTIMEWIN
46 #elif defined(LUA_USE_C89)
47 #define LUA_STRFTIMEOPTIONS	L_STRFTIMEC89
48 #else  /* C99 specification */
49 #define LUA_STRFTIMEOPTIONS	L_STRFTIMEC99
50 #endif
51 
52 #endif					/* } */
53 /* }================================================================== */
54 
55 
56 /*
57 ** {==================================================================
58 ** Configuration for time-related stuff
59 ** ===================================================================
60 */
61 
62 /*
63 ** type to represent time_t in Lua
64 */
65 #if !defined(LUA_NUMTIME)	/* { */
66 
67 #define l_timet			lua_Integer
68 #define l_pushtime(L,t)		lua_pushinteger(L,(lua_Integer)(t))
69 #define l_gettime(L,arg)	luaL_checkinteger(L, arg)
70 
71 #else				/* }{ */
72 
73 #define l_timet			lua_Number
74 #define l_pushtime(L,t)		lua_pushnumber(L,(lua_Number)(t))
75 #define l_gettime(L,arg)	luaL_checknumber(L, arg)
76 
77 #endif				/* } */
78 
79 
80 #if !defined(l_gmtime)		/* { */
81 /*
82 ** By default, Lua uses gmtime/localtime, except when POSIX is available,
83 ** where it uses gmtime_r/localtime_r
84 */
85 
86 #if defined(LUA_USE_POSIX)	/* { */
87 
88 #define l_gmtime(t,r)		gmtime_r(t,r)
89 #define l_localtime(t,r)	localtime_r(t,r)
90 
91 #else				/* }{ */
92 
93 /* ISO C definitions */
94 #define l_gmtime(t,r)		((void)(r)->tm_sec, gmtime(t))
95 #define l_localtime(t,r)	((void)(r)->tm_sec, localtime(t))
96 
97 #endif				/* } */
98 
99 #endif				/* } */
100 
101 /* }================================================================== */
102 
103 
104 /*
105 ** {==================================================================
106 ** Configuration for 'tmpnam':
107 ** By default, Lua uses tmpnam except when POSIX is available, where
108 ** it uses mkstemp.
109 ** ===================================================================
110 */
111 #if !defined(lua_tmpnam)	/* { */
112 
113 #if defined(LUA_USE_POSIX)	/* { */
114 
115 #include <unistd.h>
116 
117 #define LUA_TMPNAMBUFSIZE	32
118 
119 #if !defined(LUA_TMPNAMTEMPLATE)
120 #define LUA_TMPNAMTEMPLATE	"/tmp/lua_XXXXXX"
121 #endif
122 
123 #define lua_tmpnam(b,e) { \
124         strcpy(b, LUA_TMPNAMTEMPLATE); \
125         e = mkstemp(b); \
126         if (e != -1) close(e); \
127         e = (e == -1); }
128 
129 #else				/* }{ */
130 
131 /* ISO C definitions */
132 #define LUA_TMPNAMBUFSIZE	L_tmpnam
133 #define lua_tmpnam(b,e)		{ e = (tmpnam(b) == NULL); }
134 
135 #endif				/* } */
136 
137 #endif				/* } */
138 /* }================================================================== */
139 
140 
141 
os_execute(lua_State * L)142 static int os_execute (lua_State *L) {
143   const char *cmd = luaL_optstring(L, 1, NULL);
144   int stat;
145   errno = 0;
146   stat = system(cmd);
147   if (cmd != NULL)
148     return luaL_execresult(L, stat);
149   else {
150     lua_pushboolean(L, stat);  /* true if there is a shell */
151     return 1;
152   }
153 }
154 
155 
os_remove(lua_State * L)156 static int os_remove (lua_State *L) {
157   const char *filename = luaL_checkstring(L, 1);
158   return luaL_fileresult(L, remove(filename) == 0, filename);
159 }
160 
161 
os_rename(lua_State * L)162 static int os_rename (lua_State *L) {
163   const char *fromname = luaL_checkstring(L, 1);
164   const char *toname = luaL_checkstring(L, 2);
165   return luaL_fileresult(L, rename(fromname, toname) == 0, NULL);
166 }
167 
168 
os_tmpname(lua_State * L)169 static int os_tmpname (lua_State *L) {
170   char buff[LUA_TMPNAMBUFSIZE];
171   int err;
172   lua_tmpnam(buff, err);
173   if (l_unlikely(err))
174     return luaL_error(L, "unable to generate a unique filename");
175   lua_pushstring(L, buff);
176   return 1;
177 }
178 
179 
os_getenv(lua_State * L)180 static int os_getenv (lua_State *L) {
181   lua_pushstring(L, getenv(luaL_checkstring(L, 1)));  /* if NULL push nil */
182   return 1;
183 }
184 
185 
os_clock(lua_State * L)186 static int os_clock (lua_State *L) {
187   lua_pushnumber(L, ((lua_Number)clock())/(lua_Number)CLOCKS_PER_SEC);
188   return 1;
189 }
190 
191 
192 /*
193 ** {======================================================
194 ** Time/Date operations
195 ** { year=%Y, month=%m, day=%d, hour=%H, min=%M, sec=%S,
196 **   wday=%w+1, yday=%j, isdst=? }
197 ** =======================================================
198 */
199 
200 /*
201 ** About the overflow check: an overflow cannot occur when time
202 ** is represented by a lua_Integer, because either lua_Integer is
203 ** large enough to represent all int fields or it is not large enough
204 ** to represent a time that cause a field to overflow.  However, if
205 ** times are represented as doubles and lua_Integer is int, then the
206 ** time 0x1.e1853b0d184f6p+55 would cause an overflow when adding 1900
207 ** to compute the year.
208 */
setfield(lua_State * L,const char * key,int value,int delta)209 static void setfield (lua_State *L, const char *key, int value, int delta) {
210   #if (defined(LUA_NUMTIME) && LUA_MAXINTEGER <= INT_MAX)
211     if (l_unlikely(value > LUA_MAXINTEGER - delta))
212       luaL_error(L, "field '%s' is out-of-bound", key);
213   #endif
214   lua_pushinteger(L, (lua_Integer)value + delta);
215   lua_setfield(L, -2, key);
216 }
217 
218 
setboolfield(lua_State * L,const char * key,int value)219 static void setboolfield (lua_State *L, const char *key, int value) {
220   if (value < 0)  /* undefined? */
221     return;  /* does not set field */
222   lua_pushboolean(L, value);
223   lua_setfield(L, -2, key);
224 }
225 
226 
227 /*
228 ** Set all fields from structure 'tm' in the table on top of the stack
229 */
setallfields(lua_State * L,struct tm * stm)230 static void setallfields (lua_State *L, struct tm *stm) {
231   setfield(L, "year", stm->tm_year, 1900);
232   setfield(L, "month", stm->tm_mon, 1);
233   setfield(L, "day", stm->tm_mday, 0);
234   setfield(L, "hour", stm->tm_hour, 0);
235   setfield(L, "min", stm->tm_min, 0);
236   setfield(L, "sec", stm->tm_sec, 0);
237   setfield(L, "yday", stm->tm_yday, 1);
238   setfield(L, "wday", stm->tm_wday, 1);
239   setboolfield(L, "isdst", stm->tm_isdst);
240 }
241 
242 
getboolfield(lua_State * L,const char * key)243 static int getboolfield (lua_State *L, const char *key) {
244   int res;
245   res = (lua_getfield(L, -1, key) == LUA_TNIL) ? -1 : lua_toboolean(L, -1);
246   lua_pop(L, 1);
247   return res;
248 }
249 
250 
getfield(lua_State * L,const char * key,int d,int delta)251 static int getfield (lua_State *L, const char *key, int d, int delta) {
252   int isnum;
253   int t = lua_getfield(L, -1, key);  /* get field and its type */
254   lua_Integer res = lua_tointegerx(L, -1, &isnum);
255   if (!isnum) {  /* field is not an integer? */
256     if (l_unlikely(t != LUA_TNIL))  /* some other value? */
257       return luaL_error(L, "field '%s' is not an integer", key);
258     else if (l_unlikely(d < 0))  /* absent field; no default? */
259       return luaL_error(L, "field '%s' missing in date table", key);
260     res = d;
261   }
262   else {
263     /* unsigned avoids overflow when lua_Integer has 32 bits */
264     if (!(res >= 0 ? (lua_Unsigned)res <= (lua_Unsigned)INT_MAX + delta
265                    : (lua_Integer)INT_MIN + delta <= res))
266       return luaL_error(L, "field '%s' is out-of-bound", key);
267     res -= delta;
268   }
269   lua_pop(L, 1);
270   return (int)res;
271 }
272 
273 
checkoption(lua_State * L,const char * conv,ptrdiff_t convlen,char * buff)274 static const char *checkoption (lua_State *L, const char *conv,
275                                 ptrdiff_t convlen, char *buff) {
276   const char *option = LUA_STRFTIMEOPTIONS;
277   int oplen = 1;  /* length of options being checked */
278   for (; *option != '\0' && oplen <= convlen; option += oplen) {
279     if (*option == '|')  /* next block? */
280       oplen++;  /* will check options with next length (+1) */
281     else if (memcmp(conv, option, oplen) == 0) {  /* match? */
282       memcpy(buff, conv, oplen);  /* copy valid option to buffer */
283       buff[oplen] = '\0';
284       return conv + oplen;  /* return next item */
285     }
286   }
287   luaL_argerror(L, 1,
288     lua_pushfstring(L, "invalid conversion specifier '%%%s'", conv));
289   return conv;  /* to avoid warnings */
290 }
291 
292 
l_checktime(lua_State * L,int arg)293 static time_t l_checktime (lua_State *L, int arg) {
294   l_timet t = l_gettime(L, arg);
295   luaL_argcheck(L, (time_t)t == t, arg, "time out-of-bounds");
296   return (time_t)t;
297 }
298 
299 
300 /* maximum size for an individual 'strftime' item */
301 #define SIZETIMEFMT	250
302 
303 
os_date(lua_State * L)304 static int os_date (lua_State *L) {
305   size_t slen;
306   const char *s = luaL_optlstring(L, 1, "%c", &slen);
307   time_t t = luaL_opt(L, l_checktime, 2, time(NULL));
308   const char *se = s + slen;  /* 's' end */
309   struct tm tmr, *stm;
310   if (*s == '!') {  /* UTC? */
311     stm = l_gmtime(&t, &tmr);
312     s++;  /* skip '!' */
313   }
314   else
315     stm = l_localtime(&t, &tmr);
316   if (stm == NULL)  /* invalid date? */
317     return luaL_error(L,
318                  "date result cannot be represented in this installation");
319   if (strcmp(s, "*t") == 0) {
320     lua_createtable(L, 0, 9);  /* 9 = number of fields */
321     setallfields(L, stm);
322   }
323   else {
324     char cc[4];  /* buffer for individual conversion specifiers */
325     luaL_Buffer b;
326     cc[0] = '%';
327     luaL_buffinit(L, &b);
328     while (s < se) {
329       if (*s != '%')  /* not a conversion specifier? */
330         luaL_addchar(&b, *s++);
331       else {
332         size_t reslen;
333         char *buff = luaL_prepbuffsize(&b, SIZETIMEFMT);
334         s++;  /* skip '%' */
335         s = checkoption(L, s, se - s, cc + 1);  /* copy specifier to 'cc' */
336         reslen = strftime(buff, SIZETIMEFMT, cc, stm);
337         luaL_addsize(&b, reslen);
338       }
339     }
340     luaL_pushresult(&b);
341   }
342   return 1;
343 }
344 
345 
os_time(lua_State * L)346 static int os_time (lua_State *L) {
347   time_t t;
348   if (lua_isnoneornil(L, 1))  /* called without args? */
349     t = time(NULL);  /* get current time */
350   else {
351     struct tm ts;
352     luaL_checktype(L, 1, LUA_TTABLE);
353     lua_settop(L, 1);  /* make sure table is at the top */
354     ts.tm_year = getfield(L, "year", -1, 1900);
355     ts.tm_mon = getfield(L, "month", -1, 1);
356     ts.tm_mday = getfield(L, "day", -1, 0);
357     ts.tm_hour = getfield(L, "hour", 12, 0);
358     ts.tm_min = getfield(L, "min", 0, 0);
359     ts.tm_sec = getfield(L, "sec", 0, 0);
360     ts.tm_isdst = getboolfield(L, "isdst");
361     t = mktime(&ts);
362     setallfields(L, &ts);  /* update fields with normalized values */
363   }
364   if (t != (time_t)(l_timet)t || t == (time_t)(-1))
365     return luaL_error(L,
366                   "time result cannot be represented in this installation");
367   l_pushtime(L, t);
368   return 1;
369 }
370 
371 
os_difftime(lua_State * L)372 static int os_difftime (lua_State *L) {
373   time_t t1 = l_checktime(L, 1);
374   time_t t2 = l_checktime(L, 2);
375   lua_pushnumber(L, (lua_Number)difftime(t1, t2));
376   return 1;
377 }
378 
379 /* }====================================================== */
380 
381 
os_setlocale(lua_State * L)382 static int os_setlocale (lua_State *L) {
383   static const int cat[] = {LC_ALL, LC_COLLATE, LC_CTYPE, LC_MONETARY,
384                       LC_NUMERIC, LC_TIME};
385   static const char *const catnames[] = {"all", "collate", "ctype", "monetary",
386      "numeric", "time", NULL};
387   const char *l = luaL_optstring(L, 1, NULL);
388   int op = luaL_checkoption(L, 2, "all", catnames);
389   lua_pushstring(L, setlocale(cat[op], l));
390   return 1;
391 }
392 
393 
os_exit(lua_State * L)394 static int os_exit (lua_State *L) {
395   int status;
396   if (lua_isboolean(L, 1))
397     status = (lua_toboolean(L, 1) ? EXIT_SUCCESS : EXIT_FAILURE);
398   else
399     status = (int)luaL_optinteger(L, 1, EXIT_SUCCESS);
400   if (lua_toboolean(L, 2))
401     lua_close(L);
402   if (L) exit(status);  /* 'if' to avoid warnings for unreachable 'return' */
403   return 0;
404 }
405 
406 
407 static const luaL_Reg syslib[] = {
408   {"clock",     os_clock},
409   {"date",      os_date},
410   {"difftime",  os_difftime},
411   {"execute",   os_execute},
412   {"exit",      os_exit},
413   {"getenv",    os_getenv},
414   {"remove",    os_remove},
415   {"rename",    os_rename},
416   {"setlocale", os_setlocale},
417   {"time",      os_time},
418   {"tmpname",   os_tmpname},
419   {NULL, NULL}
420 };
421 
422 /* }====================================================== */
423 
424 
425 
luaopen_os(lua_State * L)426 LUAMOD_API int luaopen_os (lua_State *L) {
427   luaL_newlib(L, syslib);
428   return 1;
429 }
430 
431