loslib.c revision 1.9 
1/*	$NetBSD: loslib.c,v 1.9 2017/04/26 12:49:34 mbalmer Exp $	*/
2
3/*
4** Id: loslib.c,v 1.65 2016/07/18 17:58:58 roberto Exp
5** Standard Operating System library
6** See Copyright Notice in lua.h
7*/
8
9#define loslib_c
10#define LUA_LIB
11
12#include "lprefix.h"
13
14
15#include <errno.h>
16#include <locale.h>
17#include <stdlib.h>
18#include <string.h>
19#include <time.h>
20
21#include "lua.h"
22
23#include "lauxlib.h"
24#include "lualib.h"
25
26
27/*
28** {==================================================================
29** List of valid conversion specifiers for the 'strftime' function;
30** options are grouped by length; group of length 2 start with '||'.
31** ===================================================================
32*/
33#if !defined(LUA_STRFTIMEOPTIONS)	/* { */
34
35/* options for ANSI C 89 (only 1-char options) */
36#define L_STRFTIMEC89		"aAbBcdHIjmMpSUwWxXyYZ%"
37
38/* options for ISO C 99 and POSIX */
39#define L_STRFTIMEC99 "aAbBcCdDeFgGhHIjmMnprRStTuUVwWxXyYzZ%" \
40    "||" "EcECExEXEyEY" "OdOeOHOIOmOMOSOuOUOVOwOWOy"  /* two-char options */
41
42/* options for Windows */
43#define L_STRFTIMEWIN "aAbBcdHIjmMpSUwWxXyYzZ%" \
44    "||" "#c#x#d#H#I#j#m#M#S#U#w#W#y#Y"  /* two-char options */
45
46#if defined(LUA_USE_WINDOWS)
47#define LUA_STRFTIMEOPTIONS	L_STRFTIMEWIN
48#elif defined(LUA_USE_C89)
49#define LUA_STRFTIMEOPTIONS	L_STRFTIMEC89
50#else  /* C99 specification */
51#define LUA_STRFTIMEOPTIONS	L_STRFTIMEC99
52#endif
53
54#endif					/* } */
55/* }================================================================== */
56
57
58/*
59** {==================================================================
60** Configuration for time-related stuff
61** ===================================================================
62*/
63
64#if !defined(l_time_t)		/* { */
65/*
66** type to represent time_t in Lua
67*/
68#define l_timet			lua_Integer
69#define l_pushtime(L,t)		lua_pushinteger(L,(lua_Integer)(t))
70
71static time_t l_checktime (lua_State *L, int arg) {
72  lua_Integer t = luaL_checkinteger(L, arg);
73  luaL_argcheck(L, (time_t)t == t, arg, "time out-of-bounds");
74  return (time_t)t;
75}
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
142
143static int os_execute (lua_State *L) {
144  const char *cmd = luaL_optstring(L, 1, NULL);
145  int stat = system(cmd);
146  if (cmd != NULL)
147    return luaL_execresult(L, stat);
148  else {
149    lua_pushboolean(L, stat);  /* true if there is a shell */
150    return 1;
151  }
152}
153
154
155static int os_remove (lua_State *L) {
156  const char *filename = luaL_checkstring(L, 1);
157  return luaL_fileresult(L, remove(filename) == 0, filename);
158}
159
160
161static int os_rename (lua_State *L) {
162  const char *fromname = luaL_checkstring(L, 1);
163  const char *toname = luaL_checkstring(L, 2);
164  return luaL_fileresult(L, rename(fromname, toname) == 0, NULL);
165}
166
167
168static int os_tmpname (lua_State *L) {
169  char buff[LUA_TMPNAMBUFSIZE];
170  int err;
171  lua_tmpnam(buff, err);
172  if (err)
173    return luaL_error(L, "unable to generate a unique filename");
174  lua_pushstring(L, buff);
175  return 1;
176}
177
178
179static int os_getenv (lua_State *L) {
180  lua_pushstring(L, getenv(luaL_checkstring(L, 1)));  /* if NULL push nil */
181  return 1;
182}
183
184
185static int os_clock (lua_State *L) {
186  lua_pushnumber(L, ((lua_Number)clock())/(lua_Number)CLOCKS_PER_SEC);
187  return 1;
188}
189
190
191/*
192** {======================================================
193** Time/Date operations
194** { year=%Y, month=%m, day=%d, hour=%H, min=%M, sec=%S,
195**   wday=%w+1, yday=%j, isdst=? }
196** =======================================================
197*/
198
199static void setfield (lua_State *L, const char *key, int value) {
200  lua_pushinteger(L, value);
201  lua_setfield(L, -2, key);
202}
203
204static void setboolfield (lua_State *L, const char *key, int value) {
205  if (value < 0)  /* undefined? */
206    return;  /* does not set field */
207  lua_pushboolean(L, value);
208  lua_setfield(L, -2, key);
209}
210
211
212/*
213** Set all fields from structure 'tm' in the table on top of the stack
214*/
215static void setallfields (lua_State *L, struct tm *stm) {
216  setfield(L, "sec", stm->tm_sec);
217  setfield(L, "min", stm->tm_min);
218  setfield(L, "hour", stm->tm_hour);
219  setfield(L, "day", stm->tm_mday);
220  setfield(L, "month", stm->tm_mon + 1);
221  setfield(L, "year", stm->tm_year + 1900);
222  setfield(L, "wday", stm->tm_wday + 1);
223  setfield(L, "yday", stm->tm_yday + 1);
224  setboolfield(L, "isdst", stm->tm_isdst);
225}
226
227
228static int getboolfield (lua_State *L, const char *key) {
229  int res;
230  res = (lua_getfield(L, -1, key) == LUA_TNIL) ? -1 : lua_toboolean(L, -1);
231  lua_pop(L, 1);
232  return res;
233}
234
235
236/* maximum value for date fields (to avoid arithmetic overflows with 'int') */
237#if !defined(L_MAXDATEFIELD)
238#define L_MAXDATEFIELD	(INT_MAX / 2)
239#endif
240
241static int getfield (lua_State *L, const char *key, int d, int delta) {
242  int isnum;
243  int t = lua_getfield(L, -1, key);  /* get field and its type */
244  lua_Integer res = lua_tointegerx(L, -1, &isnum);
245  if (!isnum) {  /* field is not an integer? */
246    if (t != LUA_TNIL)  /* some other value? */
247      return luaL_error(L, "field '%s' is not an integer", key);
248    else if (d < 0)  /* absent field; no default? */
249      return luaL_error(L, "field '%s' missing in date table", key);
250    res = d;
251  }
252  else {
253    if (!(-L_MAXDATEFIELD <= res && res <= L_MAXDATEFIELD))
254      return luaL_error(L, "field '%s' is out-of-bound", key);
255    res -= delta;
256  }
257  lua_pop(L, 1);
258  return (int)res;
259}
260
261
262static const char *checkoption (lua_State *L, const char *conv,
263                                ptrdiff_t convlen, char *buff) {
264  const char *option = LUA_STRFTIMEOPTIONS;
265  int oplen = 1;  /* length of options being checked */
266  for (; *option != '\0' && oplen <= convlen; option += oplen) {
267    if (*option == '|')  /* next block? */
268      oplen++;  /* will check options with next length (+1) */
269    else if (memcmp(conv, option, oplen) == 0) {  /* match? */
270      memcpy(buff, conv, oplen);  /* copy valid option to buffer */
271      buff[oplen] = '\0';
272      return conv + oplen;  /* return next item */
273    }
274  }
275  luaL_argerror(L, 1,
276    lua_pushfstring(L, "invalid conversion specifier '%%%s'", conv));
277  return conv;  /* to avoid warnings */
278}
279
280
281/* maximum size for an individual 'strftime' item */
282#define SIZETIMEFMT	250
283
284
285static int os_date (lua_State *L) {
286  size_t slen;
287  const char *s = luaL_optlstring(L, 1, "%c", &slen);
288  time_t t = luaL_opt(L, l_checktime, 2, time(NULL));
289  const char *se = s + slen;  /* 's' end */
290  struct tm tmr, *stm;
291  if (*s == '!') {  /* UTC? */
292    stm = l_gmtime(&t, &tmr);
293    s++;  /* skip '!' */
294  }
295  else
296    stm = l_localtime(&t, &tmr);
297  if (stm == NULL)  /* invalid date? */
298    luaL_error(L, "time result cannot be represented in this installation");
299  if (strcmp(s, "*t") == 0) {
300    lua_createtable(L, 0, 9);  /* 9 = number of fields */
301    setallfields(L, stm);
302  }
303  else {
304    char cc[4];  /* buffer for individual conversion specifiers */
305    luaL_Buffer b;
306    cc[0] = '%';
307    luaL_buffinit(L, &b);
308    while (s < se) {
309      if (*s != '%')  /* not a conversion specifier? */
310        luaL_addchar(&b, *s++);
311      else {
312        size_t reslen;
313        char *buff = luaL_prepbuffsize(&b, SIZETIMEFMT);
314        s++;  /* skip '%' */
315        s = checkoption(L, s, se - s, cc + 1);  /* copy specifier to 'cc' */
316        reslen = strftime(buff, SIZETIMEFMT, cc, stm);
317        luaL_addsize(&b, reslen);
318      }
319    }
320    luaL_pushresult(&b);
321  }
322  return 1;
323}
324
325
326static int os_time (lua_State *L) {
327  time_t t;
328  if (lua_isnoneornil(L, 1))  /* called without args? */
329    t = time(NULL);  /* get current time */
330  else {
331    struct tm ts;
332    luaL_checktype(L, 1, LUA_TTABLE);
333    lua_settop(L, 1);  /* make sure table is at the top */
334    ts.tm_sec = getfield(L, "sec", 0, 0);
335    ts.tm_min = getfield(L, "min", 0, 0);
336    ts.tm_hour = getfield(L, "hour", 12, 0);
337    ts.tm_mday = getfield(L, "day", -1, 0);
338    ts.tm_mon = getfield(L, "month", -1, 1);
339    ts.tm_year = getfield(L, "year", -1, 1900);
340    ts.tm_isdst = getboolfield(L, "isdst");
341    t = mktime(&ts);
342    setallfields(L, &ts);  /* update fields with normalized values */
343  }
344  if (t != (time_t)(l_timet)t || t == (time_t)(-1))
345    luaL_error(L, "time result cannot be represented in this installation");
346  l_pushtime(L, t);
347  return 1;
348}
349
350
351static int os_difftime (lua_State *L) {
352  time_t t1 = l_checktime(L, 1);
353  time_t t2 = l_checktime(L, 2);
354  lua_pushnumber(L, (lua_Number)difftime(t1, t2));
355  return 1;
356}
357
358/* }====================================================== */
359
360
361static int os_setlocale (lua_State *L) {
362  static const int cat[] = {LC_ALL, LC_COLLATE, LC_CTYPE, LC_MONETARY,
363                      LC_NUMERIC, LC_TIME};
364  static const char *const catnames[] = {"all", "collate", "ctype", "monetary",
365     "numeric", "time", NULL};
366  const char *l = luaL_optstring(L, 1, NULL);
367  int op = luaL_checkoption(L, 2, "all", catnames);
368  lua_pushstring(L, setlocale(cat[op], l));
369  return 1;
370}
371
372
373static int os_exit (lua_State *L) {
374  int status;
375  if (lua_isboolean(L, 1))
376    status = (lua_toboolean(L, 1) ? EXIT_SUCCESS : EXIT_FAILURE);
377  else
378    status = (int)luaL_optinteger(L, 1, EXIT_SUCCESS);
379  if (lua_toboolean(L, 2))
380    lua_close(L);
381  if (L) exit(status);  /* 'if' to avoid warnings for unreachable 'return' */
382  return 0;
383}
384
385
386static const luaL_Reg syslib[] = {
387  {"clock",     os_clock},
388  {"date",      os_date},
389  {"difftime",  os_difftime},
390  {"execute",   os_execute},
391  {"exit",      os_exit},
392  {"getenv",    os_getenv},
393  {"remove",    os_remove},
394  {"rename",    os_rename},
395  {"setlocale", os_setlocale},
396  {"time",      os_time},
397  {"tmpname",   os_tmpname},
398  {NULL, NULL}
399};
400
401/* }====================================================== */
402
403
404
405LUAMOD_API int luaopen_os (lua_State *L) {
406  luaL_newlib(L, syslib);
407  return 1;
408}
409
410