Prevent endless loop in except2.
[wine] / msdos / int13.c
1 /*
2  * BIOS interrupt 13h handler
3  */
4
5 #include <stdlib.h>
6 #include <unistd.h>
7 #include <sys/types.h>
8 #include <sys/stat.h>
9 #include <sys/ioctl.h>
10 #include <fcntl.h>
11 #ifdef linux
12 #include <linux/fd.h>
13 #endif
14 #include "miscemu.h"
15 /* #define DEBUG_INT */
16 #include "debugtools.h"
17 #include "drive.h"
18
19 DEFAULT_DEBUG_CHANNEL(int)
20
21 /**********************************************************************
22  *          INT_Int13Handler
23  *
24  * Handler for int 13h (disk I/O).
25  */
26 void WINAPI INT_Int13Handler( CONTEXT86 *context )
27 {
28     switch(AH_reg(context))
29     {
30         case 0x00:                            /* RESET DISK SYSTEM     */
31                 break; /* no return ? */
32         case 0x01:                            /* STATUS OF DISK SYSTEM */
33                 AL_reg(context) = 0; /* successful completion */
34                 break;
35         case 0x02:                            /* READ SECTORS INTO MEMORY */
36                 AL_reg(context) = 0; /* number of sectors read */
37                 AH_reg(context) = 0; /* status */
38                 break;
39         case 0x03:                            /* WRITE SECTORS FROM MEMORY */
40                 break; /* no return ? */
41         case 0x04:                            /* VERIFY DISK SECTOR(S) */
42                 AL_reg(context) = 0; /* number of sectors verified */
43                 AH_reg(context) = 0;
44                 break;
45                
46         case 0x05:                                     /* FORMAT TRACK */
47         case 0x06:             /* FORMAT TRACK AND SET BAD SECTOR FLAGS */
48         case 0x07:             /* FORMAT DRIVE STARTING AT GIVEN TRACK  */
49             /* despite what Ralf Brown says, 0x06 and 0x07 seem to
50              * set CFLAG, too (at least my BIOS does that) */
51             AH_reg(context) = 0x0c;
52             SET_CFLAG(context);
53             break;
54
55         case 0x08:                              /* GET DRIVE PARAMETERS  */
56                 if (DL_reg(context) & 0x80) { /* hard disk ? */
57                         AH_reg(context) = 0x07;
58                         SET_CFLAG(context);
59                 }
60                 else { /* floppy disk */
61 #ifdef linux
62                         unsigned int i, nr_of_drives = 0;                       
63                         BYTE drive_nr = DL_reg(context);
64                         int floppy_fd;
65                         struct floppy_drive_params floppy_parm;
66
67                         AH_reg(context) = 0x00; /* success */
68
69                         for (i = 0; i < MAX_DOS_DRIVES; i++)
70                         if (DRIVE_GetType(i) == TYPE_FLOPPY) nr_of_drives++;
71                         DL_reg(context) = nr_of_drives;
72
73                         if (drive_nr > 1) { /* invalid drive ? */
74                                 BX_reg(context) = 0;
75                                 CX_reg(context) = 0;
76                                 DH_reg(context) = 0;
77                                 break;
78                         }
79
80                         if ( (floppy_fd = DRIVE_OpenDevice( drive_nr, O_NONBLOCK)) == -1)
81                         {
82                                 WARN("(GET DRIVE PARAMETERS): Can't determine floppy geometry !\n");
83                                 BX_reg(context) = 0;
84                                 CX_reg(context) = 0;
85                                 DH_reg(context) = 0;
86                                 break;
87                         }
88                         ioctl(floppy_fd, FDGETDRVPRM, &floppy_parm);
89                         close(floppy_fd);
90
91                         BL_reg(context) = floppy_parm.cmos;
92
93                         /* CH = low eight bits of max cyl
94                            CL = max sec nr (bits 5-0),
95                            hi two bits of max cyl (bits 7-6)
96                            DH = max head nr */ 
97                         DH_reg(context) = 0x01;
98                         switch (BL_reg(context))
99                         {
100                             case 0: /* no drive */
101                                 CX_reg(context) = 0x0;
102                                 DX_reg(context) = 0x0;
103                                 break;
104                             case 1: /* 360 K */
105                                 CX_reg(context) = 0x2709;
106                                 break;
107                             case 2: /* 1.2 M */
108                                 CX_reg(context) = 0x4f0f;
109                                 break;
110                             case 3: /* 720 K */
111                                 CX_reg(context) = 0x4f09;
112                                 break;
113                             case 4: /* 1.44 M */
114                                 CX_reg(context) = 0x4f12;
115                                 break;
116                             case 5:
117                             case 6: /* 2.88 M */
118                                 CX_reg(context) = 0x4f24;
119                                 break;
120                         }
121                         ES_reg(context) = 0x0000; /* FIXME: drive parameter table */
122                         DI_reg(context) = 0x0000;
123 #else
124                         AH_reg(context) = 0x01;
125                         SET_CFLAG(context);
126                         break;
127 #endif
128                 }
129                 break;
130
131         case 0x09:         /* INITIALIZE CONTROLLER WITH DRIVE PARAMETERS */
132         case 0x0a:         /* FIXED DISK - READ LONG (XT,AT,XT286,PS)     */
133         case 0x0b:         /* FIXED DISK - WRITE LONG (XT,AT,XT286,PS)    */
134         case 0x0c:         /* SEEK TO CYLINDER                            */
135         case 0x0d:         /* ALTERNATE RESET HARD DISKS                  */
136         case 0x10:         /* CHECK IF DRIVE READY                        */
137         case 0x11:         /* RECALIBRATE DRIVE                           */
138         case 0x14:         /* CONTROLLER INTERNAL DIAGNOSTIC              */
139                 AH_reg(context) = 0;
140                 break;
141
142         case 0x15:         /* GET DISK TYPE (AT,XT2,XT286,CONV,PS) */
143                 if (DL_reg(context) & 0x80) { /* hard disk ? */
144                         AH_reg(context) = 3; /* fixed disk */
145                         SET_CFLAG(context);
146                 }
147                 else { /* floppy disk ? */
148                         AH_reg(context) = 2; /* floppy with change detection */
149                         SET_CFLAG(context);
150                 }
151                 break;
152         case 0x0e:                    /* READ SECTOR BUFFER (XT only)      */
153         case 0x0f:                    /* WRITE SECTOR BUFFER (XT only)     */
154         case 0x12:                    /* CONTROLLER RAM DIAGNOSTIC (XT,PS) */
155         case 0x13:                    /* DRIVE DIAGNOSTIC (XT,PS)          */
156                 AH_reg(context) = 0x01;
157                 SET_CFLAG(context);
158                 break;
159
160         case 0x16:         /* FLOPPY - CHANGE OF DISK STATUS */
161                 AH_reg(context) = 0; /* FIXME - no change */
162                 break;
163         case 0x17:         /* SET DISK TYPE FOR FORMAT */
164                 if (DL_reg(context) < 4)
165                     AH_reg(context) = 0x00; /* successful completion */
166                 else
167                     AH_reg(context) = 0x01; /* error */
168                 break;
169         case 0x18:         /* SET MEDIA TYPE FOR FORMAT */
170                 if (DL_reg(context) < 4)
171                     AH_reg(context) = 0x00; /* successful completion */
172                 else
173                     AH_reg(context) = 0x01; /* error */
174                 break;
175         case 0x19:         /* FIXED DISK - PARK HEADS */
176         default:
177                 INT_BARF( context, 0x13 );
178     }
179 }