lxdream 0.9.1| filename | src/dcload.c |
| changeset | 209:ff67a7b9aa17 |
| prev | 183:5938ecc01dc8 |
| next | 422:61a0598e07ff |
| author | nkeynes |
| date | Sun Sep 16 07:03:23 2007 +0000 (16 years ago) |
| permissions | -rw-r--r-- |
| last change | Implement MAC.W, MAC.L and DIV1 Correct SHAD/SHLD Fix privilege and slot illegal checks on LDC/STC opcodes Fix various other small bugs |
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1 /**
2 * $Id: dcload.c,v 1.6 2006-08-07 13:18:16 nkeynes Exp $
3 *
4 * DC-load syscall implementation.
5 *
6 * Copyright (c) 2005 Nathan Keynes.
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation; either version 2 of the License, or
11 * (at your option) any later version.
12 *
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
17 */
19 #include <stdio.h>
20 #include "dream.h"
21 #include "dreamcast.h"
22 #include "mem.h"
23 #include "syscall.h"
24 #include "sh4/sh4core.h"
26 #define SYS_READ 0
27 #define SYS_WRITE 1
28 #define SYS_OPEN 2
29 #define SYS_CLOSE 3
30 #define SYS_CREAT 4
31 #define SYS_LINK 5
32 #define SYS_UNLINK 6
33 #define SYS_CHDIR 7
34 #define SYS_CHMOD 8
35 #define SYS_LSEEK 9
36 #define SYS_FSTAT 10
37 #define SYS_TIME 11
38 #define SYS_STAT 12
39 #define SYS_UTIME 13
40 #define SYS_ASSIGNWRKMEM 14
41 #define SYS_EXIT 15
42 #define SYS_OPENDIR 16
43 #define SYS_CLOSEDIR 17
44 #define SYS_READDIR 18
45 #define SYS_GETHOSTINFO 19
47 #define SYS_MAGIC 0xDEADBEEF
48 #define SYS_MAGIC_ADDR 0x8c004004
49 #define SYSCALL_ADDR 0x8c004008
51 static gboolean dcload_allow_unsafe = FALSE;
53 void dcload_set_allow_unsafe( gboolean allow )
54 {
55 dcload_allow_unsafe = allow;
56 }
58 #define MAX_OPEN_FDS 16
59 /**
60 * Mapping from emulator fd to real fd (so we can limit read/write
61 * to only fds we've explicitly granted access to).
62 */
63 int open_fds[MAX_OPEN_FDS];
65 int dcload_alloc_fd()
66 {
67 int i;
68 for( i=0; i<MAX_OPEN_FDS; i++ ) {
69 if( open_fds[i] == -1 ) {
70 return i;
71 }
72 }
73 return -1;
74 }
76 void dcload_syscall( uint32_t syscall_id )
77 {
78 uint32_t syscall = sh4r.r[4];
79 int fd;
80 switch( sh4r.r[4] ) {
81 case SYS_READ:
82 fd = sh4r.r[5];
83 if( fd < 0 || fd >= MAX_OPEN_FDS || open_fds[fd] == -1 ) {
84 sh4r.r[0] = -1;
85 } else {
86 char *buf = mem_get_region( sh4r.r[6] );
87 int length = sh4r.r[7];
88 sh4r.r[0] = read( open_fds[fd], buf, length );
89 }
90 break;
91 case SYS_WRITE:
92 fd = sh4r.r[5];
93 if( fd < 0 || fd >= MAX_OPEN_FDS || open_fds[fd] == -1 ) {
94 sh4r.r[0] = -1;
95 } else {
96 char *buf = mem_get_region( sh4r.r[6] );
97 int length = sh4r.r[7];
98 sh4r.r[0] = write( open_fds[fd], buf, length );
99 }
100 break;
101 case SYS_LSEEK:
102 fd = sh4r.r[5];
103 if( fd < 0 || fd >= MAX_OPEN_FDS || open_fds[fd] == -1 ) {
104 sh4r.r[0] = -1;
105 } else {
106 sh4r.r[0] = lseek( open_fds[fd], sh4r.r[6], sh4r.r[7] );
107 }
108 break;
110 /* Secure access only */
111 case SYS_OPEN:
112 if( dcload_allow_unsafe ) {
113 fd = dcload_alloc_fd();
114 if( fd == -1 ) {
115 sh4r.r[0] = -1;
116 } else {
117 char *filename = mem_get_region( sh4r.r[5] );
118 int realfd = open( filename, sh4r.r[6] );
119 open_fds[fd] = realfd;
120 sh4r.r[0] = realfd;
121 }
122 } else {
123 ERROR( "Denying access to local filesystem" );
124 sh4r.r[0] = -1;
125 }
126 break;
127 case SYS_CLOSE:
128 if( dcload_allow_unsafe ) {
129 fd = sh4r.r[5];
130 if( fd < 0 || fd >= MAX_OPEN_FDS || open_fds[fd] == -1 ) {
131 sh4r.r[0] = -1;
132 } else {
133 if( open_fds[fd] > 2 ) {
134 sh4r.r[0] = close( open_fds[fd] );
135 } else {
136 /* Don't actually close real fds 0-2 */
137 sh4r.r[0] = 0;
138 }
139 open_fds[fd] = -1;
140 }
141 }
142 break;
143 case SYS_EXIT:
144 if( dcload_allow_unsafe ) {
145 exit( sh4r.r[5] );
146 } else {
147 dreamcast_stop();
148 }
149 default:
150 sh4r.r[0] = -1;
151 }
153 }
155 void dcload_install()
156 {
157 memset( &open_fds, -1, sizeof(open_fds) );
158 open_fds[0] = 0;
159 open_fds[1] = 1;
160 open_fds[2] = 2;
161 syscall_add_hook_vector( 0xF0, SYSCALL_ADDR, dcload_syscall );
162 sh4_write_long( SYS_MAGIC_ADDR, SYS_MAGIC );
163 }
.