lua/liolib.c
1999-11-09 15:59:35 -02:00

638 lines
15 KiB
C

/*
** $Id: liolib.c,v 1.49 1999/10/26 11:00:12 roberto Exp roberto $
** Standard I/O (and system) library
** See Copyright Notice in lua.h
*/
#include <ctype.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) ((pclose(f) == -1) ? fclose(f) : 0)
#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 (const char *name) {
lua_Object f = lua_rawgetglobal(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 (const char *name, int *arg) {
FILE *f = getfile(*arg);
if (f) {
(*arg)++;
return f;
}
else
return getfilebyname(name);
}
static int closefile (FILE *f) {
if (f == stdin || f == stdout)
return 1;
else {
int tag = gettag();
lua_pushusertag(f, tag);
lua_settag(CLOSEDTAG(tag));
return (CLOSEFILE(f) == 0);
}
}
static void io_close (void) {
pushresult(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, const char *name, int tag) {
lua_pushusertag(f, tag);
lua_setglobal(name);
}
static void setreturn (FILE *f, const char *name) {
if (f == NULL)
pushresult(0);
else {
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) {
if (closefile(getfilebyname(FINPUT)))
current = stdin;
else
current = NULL; /* to signal error */
}
else if (lua_tag(f) == gettag()) /* deprecated option */
current = lua_getuserdata(f);
else {
const char *s = luaL_check_string(FIRSTARG);
current = (*s == '|') ? popen(s+1, "r") : fopen(s, "r");
}
setreturn(current, FINPUT);
}
static void io_writeto (void) {
FILE *current;
lua_Object f = lua_getparam(FIRSTARG);
if (f == LUA_NOOBJECT) {
if (closefile(getfilebyname(FOUTPUT)))
current = stdout;
else
current = NULL; /* to signal error */
}
else if (lua_tag(f) == gettag()) /* deprecated option */
current = lua_getuserdata(f);
else {
const char *s = luaL_check_string(FIRSTARG);
current = (*s == '|') ? popen(s+1,"w") : fopen(s, "w");
}
setreturn(current, FOUTPUT);
}
static void io_appendto (void) {
FILE *current = fopen(luaL_check_string(FIRSTARG), "a");
setreturn(current, FOUTPUT);
}
/*
** {======================================================
** READ
** =======================================================
*/
#ifdef COMPAT_READPATTERN
/*
** 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, const 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: {
const char *ep = luaI_classend(p); /* get what is next */
int m; /* match result */
if (c == NEED_OTHER) c = getc(f);
m = (c==EOF) ? 0 : luaI_singlematch(c, p, ep);
if (m) {
if (!inskip) luaL_addchar(c);
c = NEED_OTHER;
}
switch (*ep) {
case '+': /* repetition (1 or more) */
if (!m) goto break_while; /* pattern fails? */
/* else go through */
case '*': /* repetition (0 or more) */
while (m) { /* reads the same item until it fails */
c = getc(f);
m = (c==EOF) ? 0 : luaI_singlematch(c, p, ep);
if (m && !inskip) luaL_addchar(c);
}
/* go through to continue reading the pattern */
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');
}
#else
#define read_pattern(f,p) (lua_error("read patterns are deprecated"), 0)
#endif
static int read_number (FILE *f) {
double d;
if (fscanf(f, "%lf", &d) == 1) {
lua_pushnumber(d);
return 1;
}
else return 0; /* read fails */
}
static void read_word (FILE *f) {
int c;
do { c = fgetc(f); } while isspace(c); /* skip spaces */
while (c != EOF && !isspace(c)) {
luaL_addchar(c);
c = fgetc(f);
}
ungetc(c, f);
}
#define HUNK_LINE 256
#define HUNK_FILE BUFSIZ
static int read_line (FILE *f) {
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) {
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 int read_chars (FILE *f, int n) {
char *b = luaL_openspace(n);
int n1 = fread(b, sizeof(char), n, f);
luaL_addsize(n1);
return (n == n1);
}
static void io_read (void) {
int arg = FIRSTARG;
FILE *f = getfileparam(FINPUT, &arg);
lua_Object op = lua_getparam(arg);
do { /* repeat for each part */
long l;
int success;
luaL_resetbuffer();
if (lua_isnumber(op))
success = read_chars(f, (int)lua_getnumber(op));
else {
const char *p = luaL_opt_string(arg, "*l");
if (p[0] != '*')
success = read_pattern(f, p); /* deprecated! */
else {
switch (p[1]) {
case 'n': /* number */
if (!read_number(f)) return; /* read fails */
continue; /* number is already pushed; avoid the "pushstring" */
case 'l': /* line */
success = read_line(f);
break;
case 'a': /* file */
read_file(f);
success = 1; /* always success */
break;
case 'w': /* word */
read_word(f);
success = 0; /* must read something to succeed */
break;
default:
luaL_argerror(arg, "invalid format");
success = 0; /* to avoid warnings */
}
}
}
l = luaL_getsize();
if (!success && l==0) return; /* read fails */
lua_pushlstring(luaL_buffer(), l);
} while ((op = lua_getparam(++arg)) != LUA_NOOBJECT);
}
/* }====================================================== */
static void io_write (void) {
int arg = FIRSTARG;
FILE *f = getfileparam(FOUTPUT, &arg);
int status = 1;
lua_Object o;
while ((o = lua_getparam(arg++)) != LUA_NOOBJECT) {
switch (lua_type(o)[2]) {
case 'r': { /* stRing? */
long l = lua_strlen(o);
status = status &&
((long)fwrite(lua_getstring(o), sizeof(char), l, f) == l);
break;
}
case 'm': /* nuMber? */ /* LUA_NUMBER */
/* optimization: could be done exactly as for strings */
status = status && fprintf(f, "%.16g", lua_getnumber(o)) > 0;
break;
default: luaL_argerror(arg-1, "string expected");
}
}
pushresult(status);
}
static void io_seek (void) {
static const int mode[] = {SEEK_SET, SEEK_CUR, SEEK_END};
static const char *const 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];
const 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 const int cat[] = {LC_ALL, LC_COLLATE, LC_CTYPE, LC_MONETARY,
LC_NUMERIC, LC_TIME};
static const char *const 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) {
exit(luaL_opt_int(1, EXIT_SUCCESS));
}
/* }====================================================== */
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 60
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) {
const char *name;
int currentline;
const 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, " ");
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 %.70s", buffchunk);
else if (linedefined < 0)
sprintf(buff+strlen(buff), "%.70s", buffchunk);
else
sprintf(buff+strlen(buff), "function <%d:%.70s>",
linedefined, buffchunk);
chunkname = NULL;
}
}
if ((currentline = lua_currentline(func)) > 0)
sprintf(buff+strlen(buff), " at line %d", currentline);
if (chunkname)
sprintf(buff+strlen(buff), " [%.70s]", 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 const 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 const 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) {
unsigned 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();
}