1/*	$NetBSD: loslib.c,v 1.13 2023/06/08 21:12:08 nikita Exp $	*/
2
3/*
4** Id: loslib.c
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#if defined(LUA_USE_WINDOWS)
36#define LUA_STRFTIMEOPTIONS  "aAbBcdHIjmMpSUwWxXyYzZ%" \
37    "||" "#c#x#d#H#I#j#m#M#S#U#w#W#y#Y"  /* two-char options */
38#elif defined(LUA_USE_C89)  /* ANSI C 89 (only 1-char options) */
39#define LUA_STRFTIMEOPTIONS  "aAbBcdHIjmMpSUwWxXyYZ%"
40#else  /* C99 specification */
41#define LUA_STRFTIMEOPTIONS  "aAbBcCdDeFgGhHIjmMnprRStTuUVwWxXyYzZ%" \
42    "||" "EcECExEXEyEY" "OdOeOHOIOmOMOSOuOUOVOwOWOy"  /* two-char options */
43#endif
44
45#endif					/* } */
46/* }================================================================== */
47
48
49/*
50** {==================================================================
51** Configuration for time-related stuff
52** ===================================================================
53*/
54
55/*
56** type to represent time_t in Lua
57*/
58#if !defined(LUA_NUMTIME)	/* { */
59
60#define l_timet			lua_Integer
61#define l_pushtime(L,t)		lua_pushinteger(L,(lua_Integer)(t))
62#define l_gettime(L,arg)	luaL_checkinteger(L, arg)
63
64#else				/* }{ */
65
66#define l_timet			lua_Number
67#define l_pushtime(L,t)		lua_pushnumber(L,(lua_Number)(t))
68#define l_gettime(L,arg)	luaL_checknumber(L, arg)
69
70#endif				/* } */
71
72
73#if !defined(l_gmtime)		/* { */
74/*
75** By default, Lua uses gmtime/localtime, except when POSIX is available,
76** where it uses gmtime_r/localtime_r
77*/
78
79#if defined(LUA_USE_POSIX)	/* { */
80
81#define l_gmtime(t,r)		gmtime_r(t,r)
82#define l_localtime(t,r)	localtime_r(t,r)
83
84#else				/* }{ */
85
86/* ISO C definitions */
87#define l_gmtime(t,r)		((void)(r)->tm_sec, gmtime(t))
88#define l_localtime(t,r)	((void)(r)->tm_sec, localtime(t))
89
90#endif				/* } */
91
92#endif				/* } */
93
94/* }================================================================== */
95
96
97/*
98** {==================================================================
99** Configuration for 'tmpnam':
100** By default, Lua uses tmpnam except when POSIX is available, where
101** it uses mkstemp.
102** ===================================================================
103*/
104#if !defined(lua_tmpnam)	/* { */
105
106#if defined(LUA_USE_POSIX)	/* { */
107
108#include <unistd.h>
109
110#define LUA_TMPNAMBUFSIZE	32
111
112#if !defined(LUA_TMPNAMTEMPLATE)
113#define LUA_TMPNAMTEMPLATE	"/tmp/lua_XXXXXX"
114#endif
115
116#define lua_tmpnam(b,e) { \
117        strcpy(b, LUA_TMPNAMTEMPLATE); \
118        e = mkstemp(b); \
119        if (e != -1) close(e); \
120        e = (e == -1); }
121
122#else				/* }{ */
123
124/* ISO C definitions */
125#define LUA_TMPNAMBUFSIZE	L_tmpnam
126#define lua_tmpnam(b,e)		{ e = (tmpnam(b) == NULL); }
127
128#endif				/* } */
129
130#endif				/* } */
131/* }================================================================== */
132
133
134#if !defined(l_system)
135#if defined(LUA_USE_IOS)
136/* Despite claiming to be ISO C, iOS does not implement 'system'. */
137#define l_system(cmd) ((cmd) == NULL ? 0 : -1)
138#else
139#define l_system(cmd)	system(cmd)  /* default definition */
140#endif
141#endif
142
143
144static int os_execute (lua_State *L) {
145  const char *cmd = luaL_optstring(L, 1, NULL);
146  int stat;
147  errno = 0;
148  stat = l_system(cmd);
149  if (cmd != NULL)
150    return luaL_execresult(L, stat);
151  else {
152    lua_pushboolean(L, stat);  /* true if there is a shell */
153    return 1;
154  }
155}
156
157
158static int os_remove (lua_State *L) {
159  const char *filename = luaL_checkstring(L, 1);
160  return luaL_fileresult(L, remove(filename) == 0, filename);
161}
162
163
164static int os_rename (lua_State *L) {
165  const char *fromname = luaL_checkstring(L, 1);
166  const char *toname = luaL_checkstring(L, 2);
167  return luaL_fileresult(L, rename(fromname, toname) == 0, NULL);
168}
169
170
171static int os_tmpname (lua_State *L) {
172  char buff[LUA_TMPNAMBUFSIZE];
173  int err;
174  lua_tmpnam(buff, err);
175  if (l_unlikely(err))
176    return luaL_error(L, "unable to generate a unique filename");
177  lua_pushstring(L, buff);
178  return 1;
179}
180
181
182static int os_getenv (lua_State *L) {
183  lua_pushstring(L, getenv(luaL_checkstring(L, 1)));  /* if NULL push nil */
184  return 1;
185}
186
187
188static int os_clock (lua_State *L) {
189  lua_pushnumber(L, ((lua_Number)clock())/(lua_Number)CLOCKS_PER_SEC);
190  return 1;
191}
192
193
194/*
195** {======================================================
196** Time/Date operations
197** { year=%Y, month=%m, day=%d, hour=%H, min=%M, sec=%S,
198**   wday=%w+1, yday=%j, isdst=? }
199** =======================================================
200*/
201
202/*
203** About the overflow check: an overflow cannot occur when time
204** is represented by a lua_Integer, because either lua_Integer is
205** large enough to represent all int fields or it is not large enough
206** to represent a time that cause a field to overflow.  However, if
207** times are represented as doubles and lua_Integer is int, then the
208** time 0x1.e1853b0d184f6p+55 would cause an overflow when adding 1900
209** to compute the year.
210*/
211static void setfield (lua_State *L, const char *key, int value, int delta) {
212  #if (defined(LUA_NUMTIME) && LUA_MAXINTEGER <= INT_MAX)
213    if (l_unlikely(value > LUA_MAXINTEGER - delta))
214      luaL_error(L, "field '%s' is out-of-bound", key);
215  #endif
216  lua_pushinteger(L, (lua_Integer)value + delta);
217  lua_setfield(L, -2, key);
218}
219
220
221static void setboolfield (lua_State *L, const char *key, int value) {
222  if (value < 0)  /* undefined? */
223    return;  /* does not set field */
224  lua_pushboolean(L, value);
225  lua_setfield(L, -2, key);
226}
227
228
229/*
230** Set all fields from structure 'tm' in the table on top of the stack
231*/
232static void setallfields (lua_State *L, struct tm *stm) {
233  setfield(L, "year", stm->tm_year, 1900);
234  setfield(L, "month", stm->tm_mon, 1);
235  setfield(L, "day", stm->tm_mday, 0);
236  setfield(L, "hour", stm->tm_hour, 0);
237  setfield(L, "min", stm->tm_min, 0);
238  setfield(L, "sec", stm->tm_sec, 0);
239  setfield(L, "yday", stm->tm_yday, 1);
240  setfield(L, "wday", stm->tm_wday, 1);
241  setboolfield(L, "isdst", stm->tm_isdst);
242}
243
244
245static int getboolfield (lua_State *L, const char *key) {
246  int res;
247  res = (lua_getfield(L, -1, key) == LUA_TNIL) ? -1 : lua_toboolean(L, -1);
248  lua_pop(L, 1);
249  return res;
250}
251
252
253static int getfield (lua_State *L, const char *key, int d, int delta) {
254  int isnum;
255  int t = lua_getfield(L, -1, key);  /* get field and its type */
256  lua_Integer res = lua_tointegerx(L, -1, &isnum);
257  if (!isnum) {  /* field is not an integer? */
258    if (l_unlikely(t != LUA_TNIL))  /* some other value? */
259      return luaL_error(L, "field '%s' is not an integer", key);
260    else if (l_unlikely(d < 0))  /* absent field; no default? */
261      return luaL_error(L, "field '%s' missing in date table", key);
262    res = d;
263  }
264  else {
265    if (!(res >= 0 ? res - delta <= INT_MAX : 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
274static 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
293static 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
304static 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
346static 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
372static 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
382static 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
394static 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
407static 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
426LUAMOD_API int luaopen_os (lua_State *L) {
427  luaL_newlib(L, syslib);
428  return 1;
429}
430
431