loslib.c revision 1.5 
1/*	$NetBSD: loslib.c,v 1.5 2016/01/28 14:41:39 lneto Exp $	*/
2
3/*
4** Id: loslib.c,v 1.60 2015/11/19 19:16:22 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** ===================================================================
31*/
32#if !defined(LUA_STRFTIMEOPTIONS)	/* { */
33
34#if defined(LUA_USE_C89)
35#define LUA_STRFTIMEOPTIONS	{ "aAbBcdHIjmMpSUwWxXyYz%", "" }
36#else  /* C99 specification */
37#define LUA_STRFTIMEOPTIONS \
38	{ "aAbBcCdDeFgGhHIjmMnprRStTuUVwWxXyYzZ%", "", \
39	  "E", "cCxXyY",  \
40	  "O", "deHImMSuUVwWy" }
41#endif
42
43#endif					/* } */
44/* }================================================================== */
45
46
47/*
48** {==================================================================
49** Configuration for time-related stuff
50** ===================================================================
51*/
52
53#if !defined(l_time_t)		/* { */
54/*
55** type to represent time_t in Lua
56*/
57#define l_timet			lua_Integer
58#define l_pushtime(L,t)		lua_pushinteger(L,(lua_Integer)(t))
59
60static time_t l_checktime (lua_State *L, int arg) {
61  lua_Integer t = luaL_checkinteger(L, arg);
62  luaL_argcheck(L, (time_t)t == t, arg, "time out-of-bounds");
63  return (time_t)t;
64}
65
66#endif				/* } */
67
68
69#if !defined(l_gmtime)		/* { */
70/*
71** By default, Lua uses gmtime/localtime, except when POSIX is available,
72** where it uses gmtime_r/localtime_r
73*/
74
75#if defined(LUA_USE_POSIX)	/* { */
76
77#define l_gmtime(t,r)		gmtime_r(t,r)
78#define l_localtime(t,r)	localtime_r(t,r)
79
80#else				/* }{ */
81
82/* ISO C definitions */
83#define l_gmtime(t,r)		((void)(r)->tm_sec, gmtime(t))
84#define l_localtime(t,r)  	((void)(r)->tm_sec, localtime(t))
85
86#endif				/* } */
87
88#endif				/* } */
89
90/* }================================================================== */
91
92
93/*
94** {==================================================================
95** Configuration for 'tmpnam':
96** By default, Lua uses tmpnam except when POSIX is available, where
97** it uses mkstemp.
98** ===================================================================
99*/
100#if !defined(lua_tmpnam)	/* { */
101
102#if defined(LUA_USE_POSIX)	/* { */
103
104#include <unistd.h>
105
106#define LUA_TMPNAMBUFSIZE	32
107
108#if !defined(LUA_TMPNAMTEMPLATE)
109#define LUA_TMPNAMTEMPLATE	"/tmp/lua_XXXXXX"
110#endif
111
112#define lua_tmpnam(b,e) { \
113        strcpy(b, LUA_TMPNAMTEMPLATE); \
114        e = mkstemp(b); \
115        if (e != -1) close(e); \
116        e = (e == -1); }
117
118#else				/* }{ */
119
120/* ISO C definitions */
121#define LUA_TMPNAMBUFSIZE	L_tmpnam
122#define lua_tmpnam(b,e)		{ e = (tmpnam(b) == NULL); }
123
124#endif				/* } */
125
126#endif				/* } */
127/* }================================================================== */
128
129
130
131
132static int os_execute (lua_State *L) {
133  const char *cmd = luaL_optstring(L, 1, NULL);
134  int stat = system(cmd);
135  if (cmd != NULL)
136    return luaL_execresult(L, stat);
137  else {
138    lua_pushboolean(L, stat);  /* true if there is a shell */
139    return 1;
140  }
141}
142
143
144static int os_remove (lua_State *L) {
145  const char *filename = luaL_checkstring(L, 1);
146  return luaL_fileresult(L, remove(filename) == 0, filename);
147}
148
149
150static int os_rename (lua_State *L) {
151  const char *fromname = luaL_checkstring(L, 1);
152  const char *toname = luaL_checkstring(L, 2);
153  return luaL_fileresult(L, rename(fromname, toname) == 0, NULL);
154}
155
156
157static int os_tmpname (lua_State *L) {
158  char buff[LUA_TMPNAMBUFSIZE];
159  int err;
160  lua_tmpnam(buff, err);
161  if (err)
162    return luaL_error(L, "unable to generate a unique filename");
163  lua_pushstring(L, buff);
164  return 1;
165}
166
167
168static int os_getenv (lua_State *L) {
169  lua_pushstring(L, getenv(luaL_checkstring(L, 1)));  /* if NULL push nil */
170  return 1;
171}
172
173
174static int os_clock (lua_State *L) {
175  lua_pushnumber(L, ((lua_Number)clock())/(lua_Number)CLOCKS_PER_SEC);
176  return 1;
177}
178
179
180/*
181** {======================================================
182** Time/Date operations
183** { year=%Y, month=%m, day=%d, hour=%H, min=%M, sec=%S,
184**   wday=%w+1, yday=%j, isdst=? }
185** =======================================================
186*/
187
188static void setfield (lua_State *L, const char *key, int value) {
189  lua_pushinteger(L, value);
190  lua_setfield(L, -2, key);
191}
192
193static void setboolfield (lua_State *L, const char *key, int value) {
194  if (value < 0)  /* undefined? */
195    return;  /* does not set field */
196  lua_pushboolean(L, value);
197  lua_setfield(L, -2, key);
198}
199
200static int getboolfield (lua_State *L, const char *key) {
201  int res;
202  res = (lua_getfield(L, -1, key) == LUA_TNIL) ? -1 : lua_toboolean(L, -1);
203  lua_pop(L, 1);
204  return res;
205}
206
207
208/* maximum value for date fields (to avoid arithmetic overflows with 'int') */
209#if !defined(L_MAXDATEFIELD)
210#define L_MAXDATEFIELD	(INT_MAX / 2)
211#endif
212
213static int getfield (lua_State *L, const char *key, int d, int delta) {
214  int isnum;
215  int t = lua_getfield(L, -1, key);
216  lua_Integer res = lua_tointegerx(L, -1, &isnum);
217  if (!isnum) {  /* field is not a number? */
218    if (t != LUA_TNIL)  /* some other value? */
219      return luaL_error(L, "field '%s' not an integer", key);
220    else if (d < 0)  /* absent field; no default? */
221      return luaL_error(L, "field '%s' missing in date table", key);
222    res = d;
223  }
224  else {
225    if (!(-L_MAXDATEFIELD <= res && res <= L_MAXDATEFIELD))
226      return luaL_error(L, "field '%s' out-of-bounds", key);
227    res -= delta;
228  }
229  lua_pop(L, 1);
230  return (int)res;
231}
232
233
234static const char *checkoption (lua_State *L, const char *conv, char *buff) {
235  static const char *const options[] = LUA_STRFTIMEOPTIONS;
236  unsigned int i;
237  for (i = 0; i < sizeof(options)/sizeof(options[0]); i += 2) {
238    if (*conv != '\0' && strchr(options[i], *conv) != NULL) {
239      buff[1] = *conv;
240      if (*options[i + 1] == '\0') {  /* one-char conversion specifier? */
241        buff[2] = '\0';  /* end buffer */
242        return conv + 1;
243      }
244      else if (*(conv + 1) != '\0' &&
245               strchr(options[i + 1], *(conv + 1)) != NULL) {
246        buff[2] = *(conv + 1);  /* valid two-char conversion specifier */
247        buff[3] = '\0';  /* end buffer */
248        return conv + 2;
249      }
250    }
251  }
252  luaL_argerror(L, 1,
253    lua_pushfstring(L, "invalid conversion specifier '%%%s'", conv));
254  return conv;  /* to avoid warnings */
255}
256
257
258/* maximum size for an individual 'strftime' item */
259#define SIZETIMEFMT	250
260
261
262static int os_date (lua_State *L) {
263  const char *s = luaL_optstring(L, 1, "%c");
264  time_t t = luaL_opt(L, l_checktime, 2, time(NULL));
265  struct tm tmr, *stm;
266  if (*s == '!') {  /* UTC? */
267    stm = l_gmtime(&t, &tmr);
268    s++;  /* skip '!' */
269  }
270  else
271    stm = l_localtime(&t, &tmr);
272  if (stm == NULL)  /* invalid date? */
273    luaL_error(L, "time result cannot be represented in this installation");
274  if (strcmp(s, "*t") == 0) {
275    lua_createtable(L, 0, 9);  /* 9 = number of fields */
276    setfield(L, "sec", stm->tm_sec);
277    setfield(L, "min", stm->tm_min);
278    setfield(L, "hour", stm->tm_hour);
279    setfield(L, "day", stm->tm_mday);
280    setfield(L, "month", stm->tm_mon+1);
281    setfield(L, "year", stm->tm_year+1900);
282    setfield(L, "wday", stm->tm_wday+1);
283    setfield(L, "yday", stm->tm_yday+1);
284    setboolfield(L, "isdst", stm->tm_isdst);
285  }
286  else {
287    char cc[4];
288    luaL_Buffer b;
289    cc[0] = '%';
290    luaL_buffinit(L, &b);
291    while (*s) {
292      if (*s != '%')  /* not a conversion specifier? */
293        luaL_addchar(&b, *s++);
294      else {
295        size_t reslen;
296        char *buff = luaL_prepbuffsize(&b, SIZETIMEFMT);
297        s = checkoption(L, s + 1, cc);
298        reslen = strftime(buff, SIZETIMEFMT, cc, stm);
299        luaL_addsize(&b, reslen);
300      }
301    }
302    luaL_pushresult(&b);
303  }
304  return 1;
305}
306
307
308static int os_time (lua_State *L) {
309  time_t t;
310  if (lua_isnoneornil(L, 1))  /* called without args? */
311    t = time(NULL);  /* get current time */
312  else {
313    struct tm ts;
314    luaL_checktype(L, 1, LUA_TTABLE);
315    lua_settop(L, 1);  /* make sure table is at the top */
316    ts.tm_sec = getfield(L, "sec", 0, 0);
317    ts.tm_min = getfield(L, "min", 0, 0);
318    ts.tm_hour = getfield(L, "hour", 12, 0);
319    ts.tm_mday = getfield(L, "day", -1, 0);
320    ts.tm_mon = getfield(L, "month", -1, 1);
321    ts.tm_year = getfield(L, "year", -1, 1900);
322    ts.tm_isdst = getboolfield(L, "isdst");
323    t = mktime(&ts);
324  }
325  if (t != (time_t)(l_timet)t || t == (time_t)(-1))
326    luaL_error(L, "time result cannot be represented in this installation");
327  l_pushtime(L, t);
328  return 1;
329}
330
331
332static int os_difftime (lua_State *L) {
333  time_t t1 = l_checktime(L, 1);
334  time_t t2 = l_checktime(L, 2);
335  lua_pushnumber(L, (lua_Number)difftime(t1, t2));
336  return 1;
337}
338
339/* }====================================================== */
340
341
342static int os_setlocale (lua_State *L) {
343  static const int cat[] = {LC_ALL, LC_COLLATE, LC_CTYPE, LC_MONETARY,
344                      LC_NUMERIC, LC_TIME};
345  static const char *const catnames[] = {"all", "collate", "ctype", "monetary",
346     "numeric", "time", NULL};
347  const char *l = luaL_optstring(L, 1, NULL);
348  int op = luaL_checkoption(L, 2, "all", catnames);
349  lua_pushstring(L, setlocale(cat[op], l));
350  return 1;
351}
352
353
354static int os_exit (lua_State *L) {
355  int status;
356  if (lua_isboolean(L, 1))
357    status = (lua_toboolean(L, 1) ? EXIT_SUCCESS : EXIT_FAILURE);
358  else
359    status = (int)luaL_optinteger(L, 1, EXIT_SUCCESS);
360  if (lua_toboolean(L, 2))
361    lua_close(L);
362  if (L) exit(status);  /* 'if' to avoid warnings for unreachable 'return' */
363  return 0;
364}
365
366
367static const luaL_Reg syslib[] = {
368  {"clock",     os_clock},
369  {"date",      os_date},
370  {"difftime",  os_difftime},
371  {"execute",   os_execute},
372  {"exit",      os_exit},
373  {"getenv",    os_getenv},
374  {"remove",    os_remove},
375  {"rename",    os_rename},
376  {"setlocale", os_setlocale},
377  {"time",      os_time},
378  {"tmpname",   os_tmpname},
379  {NULL, NULL}
380};
381
382/* }====================================================== */
383
384
385
386LUAMOD_API int luaopen_os (lua_State *L) {
387  luaL_newlib(L, syslib);
388  return 1;
389}
390
391