lua/liolib.c
1999-04-14 17:40:32 -03:00

589 lines
13 KiB
C

/*
** $Id: liolib.c,v 1.37 1999/04/05 19:47:05 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
/* no support for locale and for strerror: fake them */
#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 IOTAG 1
#define FIRSTARG 2 /* 1st is upvalue */
#define CLOSEDTAG(tag) ((tag)-1) /* assume that CLOSEDTAG = iotag-1 */
#define FINPUT "_INPUT"
#define FOUTPUT "_OUTPUT"
#ifdef POPEN
FILE *popen();
int pclose();
#define CLOSEFILE(f) {if (pclose(f) == -1) fclose(f);}
#else
/* no support for popen */
#define popen(x,y) NULL /* that is, popen always fails */
#define CLOSEFILE(f) {fclose(f);}
#endif
static void pushresult (int i) {
if (i)
lua_pushuserdata(NULL);
else {
lua_pushnil();
lua_pushstring(strerror(errno));
lua_pushnumber(errno);
}
}
/*
** {======================================================
** FILE Operations
** =======================================================
*/
static int gettag (void) {
return (int)lua_getnumber(lua_getparam(IOTAG));
}
static int ishandle (lua_Object f) {
if (lua_isuserdata(f)) {
int tag = gettag();
if (lua_tag(f) == CLOSEDTAG(tag))
lua_error("cannot access a closed file");
return lua_tag(f) == tag;
}
else return 0;
}
static FILE *getfilebyname (char *name) {
lua_Object f = lua_getglobal(name);
if (!ishandle(f))
luaL_verror("global variable `%.50s' is not a file handle", name);
return lua_getuserdata(f);
}
static FILE *getfile (int arg) {
lua_Object f = lua_getparam(arg);
return (ishandle(f)) ? lua_getuserdata(f) : NULL;
}
static FILE *getnonullfile (int arg) {
FILE *f = getfile(arg);
luaL_arg_check(f, arg, "invalid file handle");
return f;
}
static FILE *getfileparam (char *name, int *arg) {
FILE *f = getfile(*arg);
if (f) {
(*arg)++;
return f;
}
else
return getfilebyname(name);
}
static void closefile (FILE *f) {
if (f != stdin && f != stdout) {
int tag = gettag();
CLOSEFILE(f);
lua_pushusertag(f, tag);
lua_settag(CLOSEDTAG(tag));
}
}
static void io_close (void) {
closefile(getnonullfile(FIRSTARG));
}
static void gc_close (void) {
FILE *f = getnonullfile(FIRSTARG);
if (f != stdin && f != stdout && f != stderr) {
CLOSEFILE(f);
}
}
static void io_open (void) {
FILE *f = fopen(luaL_check_string(FIRSTARG), luaL_check_string(FIRSTARG+1));
if (f) lua_pushusertag(f, gettag());
else pushresult(0);
}
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();
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(getfilebyname(FINPUT));
current = stdin;
}
else if (lua_tag(f) == gettag()) /* deprecated option */
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(getfilebyname(FOUTPUT));
current = stdout;
}
else if (lua_tag(f) == gettag()) /* deprecated option */
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) {
FILE *fp = fopen(luaL_check_string(FIRSTARG), "a");
if (fp != NULL)
setreturn(fp, FOUTPUT);
else
pushresult(0);
}
/*
** {======================================================
** READ
** =======================================================
*/
/*
** We cannot lookahead without need, because this can lock stdin.
** This flag signals when we need to read a next char.
*/
#define NEED_OTHER (EOF-1) /* just some flag different from EOF */
static int read_pattern (FILE *f, char *p) {
int inskip = 0; /* {skip} level */
int c = NEED_OTHER;
while (*p != '\0') {
switch (*p) {
case '{':
inskip++;
p++;
continue;
case '}':
if (!inskip) 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)
m = luaI_singlematch(c, p, &ep);
else {
luaI_singlematch(0, p, &ep); /* to set "ep" */
m = 0; /* EOF matches no pattern */
}
if (m) {
if (!inskip) luaL_addchar(c);
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) goto break_while; /* pattern fails? */
p = ep; /* else continues reading the pattern */
}
}
}
} break_while:
if (c != NEED_OTHER) ungetc(c, f);
return (*p == '\0');
}
static int read_number (FILE *f) {
double d;
if (fscanf(f, "%lf", &d) == 1) {
lua_pushnumber(d);
return 1;
}
else return 0; /* read fails */
}
#define HUNK_LINE 1024
#define HUNK_FILE BUFSIZ
static int read_line (FILE *f) {
/* equivalent to: return read_pattern(f, "[^\n]*{\n}"); */
int n;
char *b;
do {
b = luaL_openspace(HUNK_LINE);
if (!fgets(b, HUNK_LINE, f)) return 0; /* read fails */
n = strlen(b);
luaL_addsize(n);
} while (b[n-1] != '\n');
luaL_addsize(-1); /* remove '\n' */
return 1;
}
static void read_file (FILE *f) {
/* equivalent to: return read_pattern(f, ".*"); */
int n;
do {
char *b = luaL_openspace(HUNK_FILE);
n = fread(b, sizeof(char), HUNK_FILE, f);
luaL_addsize(n);
} while (n==HUNK_FILE);
}
static void io_read (void) {
static char *options[] = {"*n", "*l", "*a", ".*", "*w", NULL};
int arg = FIRSTARG;
FILE *f = getfileparam(FINPUT, &arg);
char *p = luaL_opt_string(arg++, "*l");
do { /* repeat for each part */
long l;
int success;
luaL_resetbuffer();
switch (luaL_findstring(p, options)) {
case 0: /* number */
if (!read_number(f)) return; /* read fails */
continue; /* number is already pushed; avoid the "pushstring" */
case 1: /* line */
success = read_line(f);
break;
case 2: case 3: /* file */
read_file(f);
success = 1; /* always success */
break;
case 4: /* word */
success = read_pattern(f, "{%s*}%S%S*");
break;
default:
success = read_pattern(f, p);
}
l = luaL_getsize();
if (!success && l==0) return; /* read fails */
lua_pushlstring(luaL_buffer(), l);
} while ((p = luaL_opt_string(arg++, NULL)) != NULL);
}
/* }====================================================== */
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 && ((long)fwrite(s, 1, l, f) == l);
pushresult(status);
}
static void io_seek (void) {
static int mode[] = {SEEK_SET, SEEK_CUR, SEEK_END};
static char *modenames[] = {"set", "cur", "end", NULL};
FILE *f = getnonullfile(FIRSTARG);
int op = luaL_findstring(luaL_opt_string(FIRSTARG+1, "cur"), modenames);
long offset = luaL_opt_long(FIRSTARG+2, 0);
luaL_arg_check(op != -1, FIRSTARG+1, "invalid mode");
op = fseek(f, offset, mode[op]);
if (op)
pushresult(0); /* error */
else
lua_pushnumber(ftell(f));
}
static void io_flush (void) {
FILE *f = getfile(FIRSTARG);
luaL_arg_check(f || lua_getparam(FIRSTARG) == LUA_NOOBJECT, FIRSTARG,
"invalid file handle");
pushresult(fflush(f) == 0);
}
/* }====================================================== */
/*
** {======================================================
** Other O.S. Operations
** =======================================================
*/
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) {
char b[256];
char *s = luaL_opt_string(1, "%c");
struct tm *tm;
time_t t;
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) {
for (;;) {
char buffer[250];
fprintf(stderr, "lua_debug> ");
if (fgets(buffer, sizeof(buffer), stdin) == 0 ||
strcmp(buffer, "cont\n") == 0)
return;
lua_dostring(buffer);
}
}
#define MESSAGESIZE 150
#define MAXMESSAGE (MESSAGESIZE*10)
#define MAXSRC 40
static void errorfb (void) {
char buff[MAXMESSAGE];
int level = 1; /* skip level 0 (it's this function) */
lua_Object func;
sprintf(buff, "lua error: %.200s\n", lua_getstring(lua_getparam(1)));
while ((func = lua_stackedfunction(level++)) != LUA_NOOBJECT) {
char *name;
int currentline;
char *chunkname;
char buffchunk[MAXSRC];
int linedefined;
lua_funcinfo(func, &chunkname, &linedefined);
luaL_chunkid(buffchunk, chunkname, sizeof(buffchunk));
if (level == 2) strcat(buff, "Active Stack:\n");
strcat(buff, "\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", buffchunk);
else if (linedefined < 0)
sprintf(buff+strlen(buff), "%.50s", buffchunk);
else
sprintf(buff+strlen(buff), "function <%d:%.50s>",
linedefined, buffchunk);
chunkname = NULL;
}
}
if ((currentline = lua_currentline(func)) > 0)
sprintf(buff+strlen(buff), " at line %d", currentline);
if (chunkname)
sprintf(buff+strlen(buff), " [%.50s]", buffchunk);
strcat(buff, "\n");
}
func = lua_rawgetglobal("_ALERT");
if (lua_isfunction(func)) { /* avoid error loop if _ALERT is not defined */
lua_pushstring(buff);
lua_callfunction(func);
}
}
static struct luaL_reg iolib[] = {
{"_ERRORMESSAGE", errorfb},
{"clock", io_clock},
{"date", io_date},
{"debug", io_debug},
{"execute", io_execute},
{"exit", io_exit},
{"getenv", io_getenv},
{"remove", io_remove},
{"rename", io_rename},
{"setlocale", setloc},
{"tmpname", io_tmpname}
};
static struct luaL_reg iolibtag[] = {
{"appendto", io_appendto},
{"closefile", io_close},
{"flush", io_flush},
{"openfile", io_open},
{"read", io_read},
{"readfrom", io_readfrom},
{"seek", io_seek},
{"write", io_write},
{"writeto", io_writeto}
};
static void openwithtags (void) {
int i;
int iotag = lua_newtag();
lua_newtag(); /* alloc CLOSEDTAG: assume that CLOSEDTAG = iotag-1 */
for (i=0; i<sizeof(iolibtag)/sizeof(iolibtag[0]); i++) {
/* put iotag as upvalue for these functions */
lua_pushnumber(iotag);
lua_pushcclosure(iolibtag[i].func, 1);
lua_setglobal(iolibtag[i].name);
}
/* predefined file handles */
setfile(stdin, FINPUT, iotag);
setfile(stdout, FOUTPUT, iotag);
setfile(stdin, "_STDIN", iotag);
setfile(stdout, "_STDOUT", iotag);
setfile(stderr, "_STDERR", iotag);
/* close file when collected */
lua_pushnumber(iotag);
lua_pushcclosure(gc_close, 1);
lua_settagmethod(iotag, "gc");
}
void lua_iolibopen (void) {
/* register lib functions */
luaL_openlib(iolib, (sizeof(iolib)/sizeof(iolib[0])));
openwithtags();
}