int21.c

freedos32的源代码

	}
	fd32_close(fd);
	res2dos(res, r);
}


/* Sub-handler for LFN service "Extended get/set attributes"
 * INT 21h AX=7143h (DS:DX->ASCIZ file name, BL=action).
 */
static inline void lfn_get_and_set_attributes(union rmregs *r)
{
	char fn[FD32_LFNPMAX];
	fd32_fs_attr_t a;
	int fd;
	int res = fix_path(fn, (const char *) FAR2ADDR(r->x.ds, r->x.dx), sizeof(fn));
	if (res < 0)
	{
		res2dos(res, r);
		return;
	}
	fd = fd32_open(fn, O_RDWR, FD32_ANONE, 0, NULL);
	if (fd < 0) /* It could be a directory... */
		fd = fd32_open(fn, O_RDWR | O_DIRECTORY, FD32_ANONE, 0, NULL);
	if (fd < 0)
	{
		res2dos(res, r);
		return;
	}
	a.Size = sizeof(fd32_fs_attr_t);
	switch (r->h.bl)
	{
		/* Get file attributes */
		case 0x00:
			res = fd32_get_attributes(fd, &a);
			if (res >= 0) r->x.cx = a.Attr;
			break;
		/* Set file attributes */
		case 0x01:
			res = fd32_get_attributes(fd, &a);
			if (res >= 0)
			{
				a.Attr = r->x.cx;
				res = fd32_set_attributes(fd, &a);
			}
			break;
		/* Get physical size of compressed file */
		/* case 0x02: Not implemented */

		/* Set last modification date and time */
		case 0x03:
			res = fd32_get_attributes(fd, &a);
			if (res >= 0)
			{
				a.MDate = r->x.di;
				a.MTime = r->x.cx;
				res = fd32_set_attributes(fd, &a);
			}
			break;
		/* Get last modification date and time */
		case 0x04:
			res = fd32_get_attributes(fd, &a);
			if (res >= 0)
			{
				r->x.di = a.MDate;
				r->x.cx = a.MTime;
			}
			break;
		/* Set last access date */
		case 0x05:
			/* DI new date in DOS format */
			res = fd32_get_attributes(fd, &a);
			if (res >= 0)
			{
				a.ADate = r->x.di;
				res = fd32_set_attributes(fd, &a);
			}
			break;
		/* Get last access date */
		case 0x06:
			res = fd32_get_attributes(fd, &a);
			if (res >= 0) r->x.di = a.ADate;
			break;
		/* Set creation date and time */
		case 0x07:
			res = fd32_get_attributes(fd, &a);
			if (res >= 0)
			{
				a.CDate = r->x.di;
				a.CTime = r->x.cx;
				a.CHund = r->x.si;
				res = fd32_set_attributes(fd, &a);
			}
			break;
		/* Get creation date and time */
		case 0x08:
			res = fd32_get_attributes(fd, &a);
			if (res >= 0)
			{
				r->x.di = a.CDate;
				r->x.cx = a.CTime;
				r->x.si = a.CHund;
			}
			break;
		/* Unsupported or invalid actions */
		default:
			fd32_close(fd);
			r->x.ax = 0x7100; /* Yet another convention */
			RMREGS_SET_CARRY;
			return;
	}
	fd32_close(fd);
	res2dos(res, r);
}


/* Sub-handler for Long File Names services
 * INT 21h AH=71h (AL=function)
 */
static inline void lfn_functions(union rmregs *r)
{
	char fn[FD32_LFNPMAX];
	int res;
	switch (r->h.al)
	{
		/* Make directory (DS:DX->ASCIZ directory name) */
		case 0x39:
			res = fix_path(fn, (const char *) FAR2ADDR(r->x.ds, r->x.dx), sizeof(fn));
			if (res >= 0) res = fd32_mkdir(fn);
			break;
		/* Remove directory (DS:DX->ASCIZ directory name) */
		case 0x3A:
			res = fix_path(fn, (const char *) FAR2ADDR(r->x.ds, r->x.dx), sizeof(fn));
			if (res >= 0) res = fd32_rmdir(fn);
			break;
		/* Change directory (DS:DX->ASCIZ directory name) */
		case 0x3B:
			res = fix_path(fn, (const char *) FAR2ADDR(r->x.ds, r->x.dx), sizeof(fn));
			if (res >= 0) res = fd32_chdir(fn);
			break;
		/* Delete file (DS:DX->ASCIZ file name, CL=search attributes,
		 * CL=must-match attributes, SI=use wildcards and attributes [0=no,1=yes]).
		 * FIXME: Parameter in SI not used.
		 */
		case 0x41:
			res = fix_path(fn, (const char *) FAR2ADDR(r->x.ds, r->x.dx), sizeof(fn));
			if (res >= 0) res = fd32_unlink(fn, ((DWORD) r->h.ch << 8) + (DWORD) r->h.cl);
			break;
		/* Extended get/set file attributes */
		case 0x43:
			lfn_get_and_set_attributes(r);
			return;
		/* Get current directory (DL=drive number [0=default, 1=A, etc.],
		 * DS:SI->260-bytes buffer for ASCIZ pathname).
		 * Same as INT 21h AH=47h, but we don't convert to 8.3 the resulting path
		 */
		case 0x47:
		{
			char  drive[2] = "A";
			char *dest = (char *) FAR2ADDR(r->x.ds, r->x.si);
			drive[0] = fd32_get_default_drive();
			if (r->h.dl) drive[0] = r->h.dl + 'A' - 1;
			res = fd32_getcwd(drive, fn);
			if (res >= 0)
			{
				strcpy(dest, fn + 1); /* Skip leading backslash */
				/* FIXME: Convert from UTF-8 to OEM */
			}
			break;
		}
		/* Find first matching file (DS:DX->ASCIZ file spec, ES:DI->find data record,
		 * CL=allowable attributes, CH=required attributes, SI=date/time format
		 * [0=Windows time, 1=DOS time]).
		 * FIXME: Parameter in SI not used.
		 */
		case 0x4E:
			res = fix_path(fn, (const char *) FAR2ADDR(r->x.ds, r->x.dx), sizeof(fn));
			if (res < 0) break;
			res = fd32_lfn_findfirst(fn, ((DWORD) r->h.ch << 8) + (DWORD) r->h.cl,
			                         (fd32_fs_lfnfind_t *) FAR2ADDR(r->x.es, r->x.di));
			res2dos(res, r);
			if (res >= 0)
			{
				r->x.ax = (WORD) res; /* The directory handle to continue the search */
				/* FIXME: Unicode conversion flags in CX not implemented
				 * bit 0 set if the returned long name contains
				 *  underscores for unconvertable Unicode characters
				 * bit 1 set if the returned short name contains
				 *  underscores for unconvertable Unicode characters
				 */
				r->x.cx = 0; 
			}
			else if (res == -ENOENT) r->x.ax = DOS_ENOMOREF;
			return;
		/* Find next matching file (ES:DI->find data record, BX=directory handle,
		 * SI=date/time format [0=Windows time, 1=DOS time]).
		 * FIXME: Same FIXMEs as case 0x4E.
		 */
		case 0x4F:
			res = fd32_lfn_findnext(r->x.bx, 0, (fd32_fs_lfnfind_t *) FAR2ADDR(r->x.es, r->x.di));
			res2dos(res, r);
			if (res >= 0) r->x.cx = 0;
			else if (res == -ENOENT) r->x.ax = DOS_ENOMOREF;
			return;
		/* Rename of move file (DS:DX->ASCIZ old name, ES:DI->ASCIZ new name) */
		case 0x56:
		{
			char newfn[FD32_LFNPMAX];
			res = fix_path(fn, (const char *) FAR2ADDR(r->x.ds, r->x.dx), sizeof(fn));
			if (res < 0) break;
			res = fix_path(newfn, (const char *) FAR2ADDR(r->x.es, r->x.di), sizeof(newfn));
			if (res >= 0) res = fd32_rename(fn, newfn);
			break;
		}
		/* Truename (CL=subfunction) */
		case 0x60:
			/* FIXME: Only subservice 01h "Get short (8.3) filename for file" is implemented */
			if (r->h.cl != 0x01)
			{
				res = -ENOTSUP;
				break;
			}
			/* CH=SUBST expansion flag (ignored), 80h to not resolve SUBST
			 * DS:SI->ASCIZ long file name or path
			 * ES:DI->64-bytes buffer for short path name
			 */
			res = fix_path(fn, (const char *) FAR2ADDR(r->x.ds, r->x.si), sizeof(fn));
			if (res >= 0) res = fd32_sfn_truename((char *) FAR2ADDR(r->x.es, r->x.di), fn);
			break;
		/* Create or open file (BX=access mode and sharing flags, CX=attributes
		 * for creation, DX=action, DS:SI->ASCIZ file name, DI=numeric tail hint).
		 */
		case 0x6C:
		{
			int action;
			res = parse_open_action(r->x.dx);
			if (res < 0) break;
			action = res;
			res = fix_path(fn, (const char *) FAR2ADDR(r->x.ds, r->x.si), sizeof(fn));
			if (res < 0) break;
			res = fd32_open(fn, action | (DWORD) r->x.bx, r->x.cx, r->x.di, &action);
			res2dos(res, r);
			if (res >= 0)
			{
				r->x.ax = (WORD) res; /* Returned handle */
				r->x.cx = (WORD) action; /* Action taken */
			}
			return;
		}
		/* Get volume informations (DS:DX->ASCIZ root directory name,
		 * ES:DI->buffer to store the file system name, CX=size of the
		 * buffer pointed by ES:DI).
		 */
		case 0xA0:
		{
			fd32_fs_info_t fsi;
			res = fix_path(fn, (const char *) FAR2ADDR(r->x.ds, r->x.dx), sizeof(fn));
			if (res < 0) break;
			fsi.Size       = sizeof(fd32_fs_info_t);
			fsi.FSNameSize = r->x.cx;
			fsi.FSName     = (char *) FAR2ADDR(r->x.es, r->x.di);
			res = fd32_get_fsinfo(fn, &fsi);
			if (res >= 0)
			{
				r->x.bx = fsi.Flags;
				r->x.cx = fsi.NameMax;
				r->x.dx = fsi.PathMax;
			}
			break;
		}
		/* "FindClose" - Terminate directory search (BX=directory handle) */
		case 0xA1:
			res = fd32_lfn_findclose(r->x.bx);
			break;
		/* Unsupported or invalid actions */
		default:
			r->x.ax = 0x7100; /* Yet another convention */
			RMREGS_SET_CARRY;
			return;
	}
	res2dos(res, r);
}


/* INT 21h handler for DOS file system services (AH=function) */
void int21_handler(union rmregs *r)
{
	int res;
	long long int res64;
	char fn[FD32_LFNPMAX];
	switch (r->h.ah)
	{
		/* DOS 1+ - Direct character input, without echo */
		case 0x07:
		{
			int tmp;
			/* Perform 1-byte read from the stdin, file handle 0.
			   1. Save the old mode of stdin
			   2. Set the stdin to the raw mode without echo
			   3. Read 1 byte from stdin and restore the old mode
			   This procedure is very alike when doing on the Win32 platform
			 */
			/* This call doesn't check for Ctrl-C or Ctrl-Break.  */
			fd32_get_attributes(0, &tmp);
			res = 0; /* Res used to set the attributes only once */
			fd32_set_attributes(0, &res);
			res = fd32_read(0, &(r->h.al), 1);
			fd32_set_attributes(0, &tmp);
			/* Return the character in AL */
			/* TODO:
			   1. Get rid of the warning: passing arg 2 of `fd32_get_attributes'
			   from incompatible pointer type, maybe using another system call?
			   2. from RBIL: if the interim console flag is set (see AX=6301h),
			   partially-formed double-byte characters may be returned
			*/
			return;
		}
		/* DOS 1+ - Set default drive (DL=drive, 0=A, etc.) */
		case 0x0E:
			LOG_PRINTF(("INT 21h - Set default drive to %02x\n", r->h.dl));
			res = fd32_set_default_drive(r->h.dl + 'A');
			if (res >= 0) return; 
			{
				/* Return the number of potentially valid drive letters in AL */
				r->h.al = (BYTE) res;
				RMREGS_CLEAR_CARRY;
			}
			/* No error code is documented. Check this. */
			return;
		/* DOS 1+ - Get default drive (in AL, 0=A, etc.) */
		case 0x19:
			r->h.al = fd32_get_default_drive() - 'A';
			LOG_PRINTF(("INT 21h - Get default drive: %02x\n", r->h.al));
			RMREGS_CLEAR_CARRY;
			return;
		/* DOS 1+ - Set Disk Transfer Area address (DS:DX->new DTA) */
		case 0x1A:
			LOG_PRINTF(("INT 21h - Set Disk Transfer Area Address: %04x:%04x\n", r->x.ds, r->x.dx));
			current_psp->dta = (void *) FAR2ADDR(r->x.ds, r->x.dx);
			return;
		/* DOS 1+ - GET SYSTEM DATE */
		case 0x2A:
		{
			fd32_date_t d;
			fd32_get_date(&d);
			r->x.cx = d.Year;
			r->h.dh = d.Mon;
			r->h.dl = d.Day;
			r->h.al = d.weekday;
			RMREGS_CLEAR_CARRY;
			return;
		}
		/* DOS 1+ - GET SYSTEM TIME */
		case 0x2C:
		{
			fd32_time_t t;
			fd32_get_time(&t);
			r->h.ch = t.Hour;
			r->h.cl = t.Min;
			r->h.dh = t.Sec;
			r->h.dl = t.Hund;
			RMREGS_CLEAR_CARRY;
			return;
		}
		/* DOS 2+ - Get Disk Transfer Area address (ES:BX <- current DTA) */
		case 0x2F:
			r->x.es = (DWORD) current_psp->dta >> 4;
			r->x.bx = (DWORD) current_psp->dta & 0xF;
			LOG_PRINTF(("INT 21h - Get Disk Transfer Area Address: %04x:%04x\n", r->x.es, r->x.bx));
			return;

		/* DOS 2+ - Get DOS version, subject to modification by SETVER
		 * (AL=what to return in BH: 0=OEM number, 1=version flag).
		 */
		case 0x30:
			LOG_PRINTF(("INT 21h - Get DOS version\n"));
			if (r->h.al) r->h.bh = 0x00; /* DOS is not in ROM (bit 3) */
			        else r->h.bh = 0xFD; /* We claim to be FreeDOS */
			/* Set the 24-bit User Serial Number to zero as we don't use it */
			r->h.bl = 0;
			r->x.cx = 0;
			r->x.ax = 0x0A07; /* We claim to be 7.10 */
			RMREGS_CLEAR_CARRY;
			return;
		/* DOS 2+ AL=06h - Get ture DOS version */
		case 0x33:
			LOG_PRINTF(("INT 21h - Get true DOS version\n"));
			if (r->h.al == 0x06)
			{
				r->x.bx = 0x0A07; /* We claim to be 7.10 */