lua/liolib.c
Roberto Ierusalimschy cc117253c8 new implementation for error handling: on error, function _ERRORMESSAGE
is called, which in turn calls _ALERT to write a message to stderr.
1998-08-21 14:43:44 -03:00

450 lines
9.8 KiB
C

/*
** $Id: liolib.c,v 1.21 1998/06/18 17:04:28 roberto Exp roberto $
** Standard I/O (and system) library
** See Copyright Notice in lua.h
*/
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>
#include "lauxlib.h"
#include "lua.h"
#include "luadebug.h"
#include "lualib.h"
#ifndef OLD_ANSI
#include <locale.h>
#else
#define setlocale(a,b) 0
#define LC_ALL 0
#define LC_COLLATE 0
#define LC_CTYPE 0
#define LC_MONETARY 0
#define LC_NUMERIC 0
#define LC_TIME 0
#define strerror(e) "(no error message provided by operating system)"
#endif
#define CLOSEDTAG 2
#define IOTAG 1
#define FIRSTARG 3 /* 1st and 2nd are upvalues */
#define FINPUT "_INPUT"
#define FOUTPUT "_OUTPUT"
#ifdef POPEN
FILE *popen();
int pclose();
#else
#define popen(x,y) NULL /* that is, popen always fails */
#define pclose(x) (-1)
#endif
static int gettag (int i)
{
return lua_getnumber(lua_getparam(i));
}
static void pushresult (int i)
{
if (i)
lua_pushuserdata(NULL);
else {
lua_pushnil();
lua_pushstring(strerror(errno));
}
}
static int ishandler (lua_Object f)
{
if (lua_isuserdata(f)) {
if (lua_tag(f) == gettag(CLOSEDTAG))
lua_error("cannot access a closed file");
return lua_tag(f) == gettag(IOTAG);
}
else return 0;
}
static FILE *getfile (char *name)
{
lua_Object f = lua_getglobal(name);
if (!ishandler(f))
luaL_verror("global variable `%.50s' is not a file handle", name);
return lua_getuserdata(f);
}
static FILE *getfileparam (char *name, int *arg)
{
lua_Object f = lua_getparam(*arg);
if (ishandler(f)) {
(*arg)++;
return lua_getuserdata(f);
}
else
return getfile(name);
}
static void closefile (char *name)
{
FILE *f = getfile(name);
if (f == stdin || f == stdout) return;
if (pclose(f) == -1)
fclose(f);
lua_pushobject(lua_getglobal(name));
lua_settag(gettag(CLOSEDTAG));
}
static void setfile (FILE *f, char *name, int tag)
{
lua_pushusertag(f, tag);
lua_setglobal(name);
}
static void setreturn (FILE *f, char *name)
{
int tag = gettag(IOTAG);
setfile(f, name, tag);
lua_pushusertag(f, tag);
}
static void io_readfrom (void)
{
FILE *current;
lua_Object f = lua_getparam(FIRSTARG);
if (f == LUA_NOOBJECT) {
closefile(FINPUT);
current = stdin;
}
else if (lua_tag(f) == gettag(IOTAG))
current = lua_getuserdata(f);
else {
char *s = luaL_check_string(FIRSTARG);
current = (*s == '|') ? popen(s+1, "r") : fopen(s, "r");
if (current == NULL) {
pushresult(0);
return;
}
}
setreturn(current, FINPUT);
}
static void io_writeto (void)
{
FILE *current;
lua_Object f = lua_getparam(FIRSTARG);
if (f == LUA_NOOBJECT) {
closefile(FOUTPUT);
current = stdout;
}
else if (lua_tag(f) == gettag(IOTAG))
current = lua_getuserdata(f);
else {
char *s = luaL_check_string(FIRSTARG);
current = (*s == '|') ? popen(s+1,"w") : fopen(s,"w");
if (current == NULL) {
pushresult(0);
return;
}
}
setreturn(current, FOUTPUT);
}
static void io_appendto (void)
{
char *s = luaL_check_string(FIRSTARG);
FILE *fp = fopen (s, "a");
if (fp != NULL)
setreturn(fp, FOUTPUT);
else
pushresult(0);
}
#define NEED_OTHER (EOF-1) /* just some flag different from EOF */
static void read_until (FILE *f, int lim) {
int l = 0;
int c;
for (c = getc(f); c != EOF && c != lim; c = getc(f)) {
luaL_addchar(c);
l++;
}
if (l > 0 || c == lim) /* read anything? */
lua_pushlstring(luaL_buffer(), l);
}
static void io_read (void) {
int arg = FIRSTARG;
FILE *f = getfileparam(FINPUT, &arg);
char *p = luaL_opt_string(arg, NULL);
luaL_resetbuffer();
if (p == NULL) /* default: read a line */
read_until(f, '\n');
else if (p[0] == '.' && p[1] == '*' && p[2] == 0) /* p = ".*" */
read_until(f, EOF);
else {
int l = 0; /* number of chars read in buffer */
int inskip = 0; /* to control {skips} */
int c = NEED_OTHER;
while (*p) {
switch (*p) {
case '{':
inskip++;
p++;
continue;
case '}':
if (inskip == 0)
lua_error("unbalanced braces in read pattern");
inskip--;
p++;
continue;
default: {
char *ep; /* get what is next */
int m; /* match result */
if (c == NEED_OTHER) c = getc(f);
if (c == EOF) {
luaI_singlematch(0, p, &ep); /* to set "ep" */
m = 0;
}
else {
m = luaI_singlematch(c, p, &ep);
if (m) {
if (inskip == 0) {
luaL_addchar(c);
l++;
}
c = NEED_OTHER;
}
}
switch (*ep) {
case '*': /* repetition */
if (!m) p = ep+1; /* else stay in (repeat) the same item */
continue;
case '?': /* optional */
p = ep+1; /* continues reading the pattern */
continue;
default:
if (m) p = ep; /* continues reading the pattern */
else
goto break_while; /* pattern fails */
}
}
}
} break_while:
if (c >= 0) /* not EOF nor NEED_OTHER? */
ungetc(c, f);
if (l > 0 || *p == 0) /* read something or did not fail? */
lua_pushlstring(luaL_buffer(), l);
}
}
static void io_write (void)
{
int arg = FIRSTARG;
FILE *f = getfileparam(FOUTPUT, &arg);
int status = 1;
char *s;
long l;
while ((s = luaL_opt_lstr(arg++, NULL, &l)) != NULL)
status = status && (fwrite(s, 1, l, f) == l);
pushresult(status);
}
static void io_execute (void)
{
lua_pushnumber(system(luaL_check_string(1)));
}
static void io_remove (void)
{
pushresult(remove(luaL_check_string(1)) == 0);
}
static void io_rename (void)
{
pushresult(rename(luaL_check_string(1),
luaL_check_string(2)) == 0);
}
static void io_tmpname (void)
{
lua_pushstring(tmpnam(NULL));
}
static void io_getenv (void)
{
lua_pushstring(getenv(luaL_check_string(1))); /* if NULL push nil */
}
static void io_clock (void) {
lua_pushnumber(((double)clock())/CLOCKS_PER_SEC);
}
static void io_date (void)
{
time_t t;
struct tm *tm;
char *s = luaL_opt_string(1, "%c");
char b[BUFSIZ];
time(&t); tm = localtime(&t);
if (strftime(b,sizeof(b),s,tm))
lua_pushstring(b);
else
lua_error("invalid `date' format");
}
static void setloc (void)
{
static int cat[] = {LC_ALL, LC_COLLATE, LC_CTYPE, LC_MONETARY, LC_NUMERIC,
LC_TIME};
static char *catnames[] = {"all", "collate", "ctype", "monetary",
"numeric", "time", NULL};
int op = luaL_findstring(luaL_opt_string(2, "all"), catnames);
luaL_arg_check(op != -1, 2, "invalid option");
lua_pushstring(setlocale(cat[op], luaL_check_string(1)));
}
static void io_exit (void)
{
lua_Object o = lua_getparam(1);
exit(lua_isnumber(o) ? (int)lua_getnumber(o) : 1);
}
static void io_debug (void)
{
while (1) {
char buffer[250];
fprintf(stderr, "lua_debug> ");
if (fgets(buffer, sizeof(buffer), stdin) == 0) return;
if (strcmp(buffer, "cont\n") == 0) return;
lua_dostring(buffer);
}
}
#define MESSAGESIZE 150
#define MAXMESSAGE (MESSAGESIZE*10)
static void errorfb (void) {
char buff[MAXMESSAGE];
int level = 1; /* skip level 0 (it's this function) */
lua_Object func;
sprintf(buff, "lua: %.200s\n", lua_getstring(lua_getparam(1)));
while ((func = lua_stackedfunction(level++)) != LUA_NOOBJECT) {
char *name;
int currentline;
char *chunkname;
int linedefined;
lua_funcinfo(func, &chunkname, &linedefined);
strcat(buff, (level==2) ? "Active Stack:\n\t" : "\t");
if (strlen(buff) > MAXMESSAGE-MESSAGESIZE) {
strcat(buff, "...\n");
break; /* buffer is full */
}
switch (*lua_getobjname(func, &name)) {
case 'g':
sprintf(buff+strlen(buff), "function %.50s", name);
break;
case 't':
sprintf(buff+strlen(buff), "`%.50s' tag method", name);
break;
default: {
if (linedefined == 0)
sprintf(buff+strlen(buff), "main of %.50s", chunkname);
else if (linedefined < 0)
sprintf(buff+strlen(buff), "%.50s", chunkname);
else
sprintf(buff+strlen(buff), "function (%.50s:%d)",
chunkname, linedefined);
chunkname = NULL;
}
}
if ((currentline = lua_currentline(func)) > 0)
sprintf(buff+strlen(buff), " at line %d", currentline);
if (chunkname)
sprintf(buff+strlen(buff), " [in chunk %.50s]", chunkname);
strcat(buff, "\n");
}
lua_pushstring(buff);
lua_call("_ALERT");
}
static struct luaL_reg iolib[] = {
{"setlocale", setloc},
{"execute", io_execute},
{"remove", io_remove},
{"rename", io_rename},
{"tmpname", io_tmpname},
{"getenv", io_getenv},
{"date", io_date},
{"clock", io_clock},
{"exit", io_exit},
{"debug", io_debug},
{"_ERRORMESSAGE", errorfb}
};
static struct luaL_reg iolibtag[] = {
{"readfrom", io_readfrom},
{"writeto", io_writeto},
{"appendto", io_appendto},
{"read", io_read},
{"write", io_write}
};
static void openwithtags (void)
{
int iotag = lua_newtag();
int closedtag = lua_newtag();
int i;
for (i=0; i<sizeof(iolibtag)/sizeof(iolibtag[0]); i++) {
/* put both tags as upvalues for these functions */
lua_pushnumber(iotag);
lua_pushnumber(closedtag);
lua_pushcclosure(iolibtag[i].func, 2);
lua_setglobal(iolibtag[i].name);
}
setfile(stdin, FINPUT, iotag);
setfile(stdout, FOUTPUT, iotag);
setfile(stdin, "_STDIN", iotag);
setfile(stdout, "_STDOUT", iotag);
setfile(stderr, "_STDERR", iotag);
}
void lua_iolibopen (void) {
luaL_openlib(iolib, (sizeof(iolib)/sizeof(iolib[0])));
openwithtags();
}