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#if defined(LUA_USE_WINDOWS)
34#define LUA_STRFTIMEOPTIONS  "aAbBcdHIjmMpSUwWxXyYzZ%" \
35    "||" "#c#x#d#H#I#j#m#M#S#U#w#W#y#Y"  /* two-char options */
36#elif defined(LUA_USE_C89)  /* ANSI C 89 (only 1-char options) */
37#define LUA_STRFTIMEOPTIONS  "aAbBcdHIjmMpSUwWxXyYZ%"
38#else  /* C99 specification */
39#define LUA_STRFTIMEOPTIONS  "aAbBcCdDeFgGhHIjmMnprRStTuUVwWxXyYzZ%" \
40    "||" "EcECExEXEyEY" "OdOeOHOIOmOMOSOuOUOVOwOWOy"  /* two-char options */
41#endif
42
43#endif					/* } */
44/* }================================================================== */
45
46
47/*
48** {==================================================================
49** Configuration for time-related stuff
50** ===================================================================
51*/
52
53/*
54** type to represent time_t in Lua
55*/
56#if !defined(LUA_NUMTIME)	/* { */
57
58#define l_timet			lua_Integer
59#define l_pushtime(L,t)		lua_pushinteger(L,(lua_Integer)(t))
60#define l_gettime(L,arg)	luaL_checkinteger(L, arg)
61
62#else				/* }{ */
63
64#define l_timet			lua_Number
65#define l_pushtime(L,t)		lua_pushnumber(L,(lua_Number)(t))
66#define l_gettime(L,arg)	luaL_checknumber(L, arg)
67
68#endif				/* } */
69
70
71#if !defined(l_gmtime)		/* { */
72/*
73** By default, Lua uses gmtime/localtime, except when POSIX is available,
74** where it uses gmtime_r/localtime_r
75*/
76
77#if defined(LUA_USE_POSIX)	/* { */
78
79#define l_gmtime(t,r)		gmtime_r(t,r)
80#define l_localtime(t,r)	localtime_r(t,r)
81
82#else				/* }{ */
83
84/* ISO C definitions */
85#define l_gmtime(t,r)		((void)(r)->tm_sec, gmtime(t))
86#define l_localtime(t,r)	((void)(r)->tm_sec, localtime(t))
87
88#endif				/* } */
89
90#endif				/* } */
91
92/* }================================================================== */
93
94
95/*
96** {==================================================================
97** Configuration for 'tmpnam':
98** By default, Lua uses tmpnam except when POSIX is available, where
99** it uses mkstemp.
100** ===================================================================
101*/
102#if !defined(lua_tmpnam)	/* { */
103
104#if defined(LUA_USE_POSIX)	/* { */
105
106#include <unistd.h>
107
108#define LUA_TMPNAMBUFSIZE	32
109
110#if !defined(LUA_TMPNAMTEMPLATE)
111#define LUA_TMPNAMTEMPLATE	"/tmp/lua_XXXXXX"
112#endif
113
114#define lua_tmpnam(b,e) { \
115        strcpy(b, LUA_TMPNAMTEMPLATE); \
116        e = mkstemp(b); \
117        if (e != -1) close(e); \
118        e = (e == -1); }
119
120#else				/* }{ */
121
122/* ISO C definitions */
123#define LUA_TMPNAMBUFSIZE	L_tmpnam
124#define lua_tmpnam(b,e)		{ e = (tmpnam(b) == NULL); }
125
126#endif				/* } */
127
128#endif				/* } */
129/* }================================================================== */
130
131
132#if !defined(l_system)
133#if defined(LUA_USE_IOS)
134/* Despite claiming to be ISO C, iOS does not implement 'system'. */
135#define l_system(cmd) ((cmd) == NULL ? 0 : -1)
136#else
137#define l_system(cmd)	system(cmd)  /* default definition */
138#endif
139#endif
140
141
142static int os_execute (lua_State *L) {
143  const char *cmd = luaL_optstring(L, 1, NULL);
144  int stat;
145  errno = 0;
146  stat = l_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
156static 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
162static 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
169static 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
180static 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
186static 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*/
209static 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
219static 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*/
230static 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
243static 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
251static 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    if (!(res >= 0 ? res - delta <= INT_MAX : INT_MIN + delta <= res))
264      return luaL_error(L, "field '%s' is out-of-bound", key);
265    res -= delta;
266  }
267  lua_pop(L, 1);
268  return (int)res;
269}
270
271
272static const char *checkoption (lua_State *L, const char *conv,
273                                ptrdiff_t convlen, char *buff) {
274  const char *option = LUA_STRFTIMEOPTIONS;
275  int oplen = 1;  /* length of options being checked */
276  for (; *option != '\0' && oplen <= convlen; option += oplen) {
277    if (*option == '|')  /* next block? */
278      oplen++;  /* will check options with next length (+1) */
279    else if (memcmp(conv, option, oplen) == 0) {  /* match? */
280      memcpy(buff, conv, oplen);  /* copy valid option to buffer */
281      buff[oplen] = '\0';
282      return conv + oplen;  /* return next item */
283    }
284  }
285  luaL_argerror(L, 1,
286    lua_pushfstring(L, "invalid conversion specifier '%%%s'", conv));
287  return conv;  /* to avoid warnings */
288}
289
290
291static time_t l_checktime (lua_State *L, int arg) {
292  l_timet t = l_gettime(L, arg);
293  luaL_argcheck(L, (time_t)t == t, arg, "time out-of-bounds");
294  return (time_t)t;
295}
296
297
298/* maximum size for an individual 'strftime' item */
299#define SIZETIMEFMT	250
300
301
302static int os_date (lua_State *L) {
303  size_t slen;
304  const char *s = luaL_optlstring(L, 1, "%c", &slen);
305  time_t t = luaL_opt(L, l_checktime, 2, time(NULL));
306  const char *se = s + slen;  /* 's' end */
307  struct tm tmr, *stm;
308  if (*s == '!') {  /* UTC? */
309    stm = l_gmtime(&t, &tmr);
310    s++;  /* skip '!' */
311  }
312  else
313    stm = l_localtime(&t, &tmr);
314  if (stm == NULL)  /* invalid date? */
315    return luaL_error(L,
316                 "date result cannot be represented in this installation");
317  if (strcmp(s, "*t") == 0) {
318    lua_createtable(L, 0, 9);  /* 9 = number of fields */
319    setallfields(L, stm);
320  }
321  else {
322    char cc[4];  /* buffer for individual conversion specifiers */
323    luaL_Buffer b;
324    cc[0] = '%';
325    luaL_buffinit(L, &b);
326    while (s < se) {
327      if (*s != '%')  /* not a conversion specifier? */
328        luaL_addchar(&b, *s++);
329      else {
330        size_t reslen;
331        char *buff = luaL_prepbuffsize(&b, SIZETIMEFMT);
332        s++;  /* skip '%' */
333        s = checkoption(L, s, se - s, cc + 1);  /* copy specifier to 'cc' */
334        reslen = strftime(buff, SIZETIMEFMT, cc, stm);
335        luaL_addsize(&b, reslen);
336      }
337    }
338    luaL_pushresult(&b);
339  }
340  return 1;
341}
342
343
344static int os_time (lua_State *L) {
345  time_t t;
346  if (lua_isnoneornil(L, 1))  /* called without args? */
347    t = time(NULL);  /* get current time */
348  else {
349    struct tm ts;
350    luaL_checktype(L, 1, LUA_TTABLE);
351    lua_settop(L, 1);  /* make sure table is at the top */
352    ts.tm_year = getfield(L, "year", -1, 1900);
353    ts.tm_mon = getfield(L, "month", -1, 1);
354    ts.tm_mday = getfield(L, "day", -1, 0);
355    ts.tm_hour = getfield(L, "hour", 12, 0);
356    ts.tm_min = getfield(L, "min", 0, 0);
357    ts.tm_sec = getfield(L, "sec", 0, 0);
358    ts.tm_isdst = getboolfield(L, "isdst");
359    t = mktime(&ts);
360    setallfields(L, &ts);  /* update fields with normalized values */
361  }
362  if (t != (time_t)(l_timet)t || t == (time_t)(-1))
363    return luaL_error(L,
364                  "time result cannot be represented in this installation");
365  l_pushtime(L, t);
366  return 1;
367}
368
369
370static int os_difftime (lua_State *L) {
371  time_t t1 = l_checktime(L, 1);
372  time_t t2 = l_checktime(L, 2);
373  lua_pushnumber(L, (lua_Number)difftime(t1, t2));
374  return 1;
375}
376
377/* }====================================================== */
378
379
380static int os_setlocale (lua_State *L) {
381  static const int cat[] = {LC_ALL, LC_COLLATE, LC_CTYPE, LC_MONETARY,
382                      LC_NUMERIC, LC_TIME};
383  static const char *const catnames[] = {"all", "collate", "ctype", "monetary",
384     "numeric", "time", NULL};
385  const char *l = luaL_optstring(L, 1, NULL);
386  int op = luaL_checkoption(L, 2, "all", catnames);
387  lua_pushstring(L, setlocale(cat[op], l));
388  return 1;
389}
390
391
392static int os_exit (lua_State *L) {
393  int status;
394  if (lua_isboolean(L, 1))
395    status = (lua_toboolean(L, 1) ? EXIT_SUCCESS : EXIT_FAILURE);
396  else
397    status = (int)luaL_optinteger(L, 1, EXIT_SUCCESS);
398  if (lua_toboolean(L, 2))
399    lua_close(L);
400  if (L) exit(status);  /* 'if' to avoid warnings for unreachable 'return' */
401  return 0;
402}
403
404
405static const luaL_Reg syslib[] = {
406  {"clock",     os_clock},
407  {"date",      os_date},
408  {"difftime",  os_difftime},
409  {"execute",   os_execute},
410  {"exit",      os_exit},
411  {"getenv",    os_getenv},
412  {"remove",    os_remove},
413  {"rename",    os_rename},
414  {"setlocale", os_setlocale},
415  {"time",      os_time},
416  {"tmpname",   os_tmpname},
417  {NULL, NULL}
418};
419
420/* }====================================================== */
421
422
423
424LUAMOD_API int luaopen_os (lua_State *L) {
425  luaL_newlib(L, syslib);
426  return 1;
427}
428
429