4 * Copyright 1998 Ove Kåven
7 #if defined(linux) && defined(__i386__)
9 /* apparently ELF images are usually loaded high anyway */
11 /* if not, force dosmod at high addresses */
26 #include <sys/types.h>
27 #include <sys/ptrace.h>
31 /* FIXME: hack because libc vm86 may be the old syscall version */
35 static inline int vm86plus( int func, struct vm86plus_struct *ptr )
39 __asm__ __volatile__( "pushl %%ebx\n\t"
48 __asm__ __volatile__("int $0x80"
54 if (res >= 0) return res;
59 int XREAD(int fd,void*buf,int size) {
63 res = read(fd, buf, size);
69 perror("dosmod read");
72 if (res) /* don't print the EOF condition */
73 fprintf(stderr,"dosmod read only %d of %d bytes.\n",res,size);
77 int XWRITE(int fd,void*buf,int size) {
81 res = write(fd, buf, size);
87 perror("dosmod write");
90 fprintf(stderr,"dosmod write only %d of %d bytes.\n",res,size);
95 void set_timer(struct timeval*tim)
101 setitimer(ITIMER_REAL,&cur,NULL);
104 void get_timer(struct timeval*tim)
106 struct itimerval cur;
108 getitimer(ITIMER_REAL,&cur);
112 volatile int sig_pend,sig_fatal=0,sig_alrm=0,sig_cb=0;
114 struct vm86plus_struct VM86;
116 void sig_handler(int sig)
118 if (sig_pend) fprintf(stderr,"DOSMOD previous signal %d lost\n",sig_pend);
120 signal(sig,sig_handler);
123 void bad_handler(int sig)
126 fprintf(stderr,"DOSMOD caught fatal signal %d\n",sig);
127 fprintf(stderr,"(Last known VM86 CS:IP was %04x:%04lx)\n",VM86.regs.cs,VM86.regs.eip);
129 sig_pend=sig; sig_fatal++;
130 signal(sig,bad_handler);
133 void alarm_handler(int sig)
136 signal(sig,alarm_handler);
139 void cb_handler(int sig)
142 signal(sig,cb_handler);
145 int main(int argc,char**argv)
147 int mfd=open(argv[0],O_RDWR);
151 pid_t ppid=getppid();
153 /* fprintf(stderr,"main is at %08lx, file is %s, fd=%d\n",(unsigned long)&main,argv[0],mfd); */
155 /* Map in our DOS image at the start of the process address space */
157 /* Ulrich Weigand suggested mapping in the DOS image directly from the Wine
160 /* linux currently only allows mapping a process memory if it's being ptraced */
161 /* Linus doesn't like it, so this probably won't work in the future */
162 /* it doesn't even work for me right now */
164 ptrace(PTRACE_ATTACH,ppid,0,0);
165 waitpid(ppid,NULL,0);
167 img=mmap(NULL,0x110000,PROT_EXEC|PROT_READ|PROT_WRITE,MAP_FIXED|MAP_SHARED,mfd,fofs);
169 ptrace(PTRACE_DETACH,ppid,0,0);
172 if (img==(void*)-1) {
173 fprintf(stderr,"DOS memory map failed, error=%s\n",strerror(errno));
174 fprintf(stderr,"in attempt to map %s, offset %08lX, length 110000, to offset 0\n",argv[0],fofs);
177 /* initialize signals and system timer */
178 signal(SIGHUP,sig_handler);
179 signal(SIGINT,sig_handler);
180 signal(SIGUSR1,sig_handler);
181 signal(SIGUSR2,cb_handler);
182 signal(SIGALRM,alarm_handler);
184 signal(SIGQUIT,bad_handler);
185 signal(SIGILL,bad_handler);
186 signal(SIGBUS,bad_handler);
187 signal(SIGFPE,bad_handler);
188 signal(SIGSEGV,bad_handler);
189 signal(SIGTERM,bad_handler);
191 tim.tv_sec=0; tim.tv_usec=54925;
194 /* report back to the main program that we're ready */
195 ret=2; /* dosmod protocol revision */
196 XWRITE(1,&ret,sizeof(ret));
197 /* context exchange loop */
199 if (XREAD(0,&func,sizeof(func))!=sizeof(func)) return 1;
202 case DOSMOD_SET_TIMER:
203 if (XREAD(0,&tim,sizeof(tim))!=sizeof(tim)) return 1;
207 case DOSMOD_GET_TIMER:
209 if (XWRITE(1,&tim,sizeof(tim))!=sizeof(tim)) return 1;
213 if (XREAD(0,&VM86,sizeof(VM86))!=sizeof(VM86)) return 1;
214 if (sig_pend||sig_alrm||sig_cb) ret=DOSMOD_SIGNAL; else
215 ret=vm86plus(func,&VM86);
216 if (XWRITE(1,&ret,sizeof(ret))!=sizeof(ret)) return 1;
217 if (XWRITE(1,&VM86,sizeof(VM86))!=sizeof(VM86)) return 1;
220 ret=sig_pend; sig_pend=0;
223 ret=SIGALRM; sig_alrm--;
225 ret=SIGUSR2; sig_cb--;
228 if (XWRITE(1,&ret,sizeof(ret))!=sizeof(ret)) return 1;
229 if (sig_fatal) return 1;
237 #else /* !linux-i386 */
238 int main(void) {return 1;}