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/* Operating system and traps for mvme187bug, the motorolola BUG
monitor for m88k */
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/times.h>
#include <errno.h>
#include "sys/systraps.h"
static void writechar(int c) {
register int n asm ("r2");
n = c;
SYSTRAP(OUTCHR);
return;
}
static int readchar(void) {
register int n asm ("r2");
SYSTRAP(INCHR);
return(n);
}
int read(int file, char *ptr, int len) {
int todo;
for (todo = len; todo; --todo) {
*ptr++ = readchar();
}
return(len);
}
int lseek(int file, int ptr, int dir) {
return 0;
}
int write(int file, char *ptr, int len) {
int todo;
for (todo = len; todo; --todo) {
writechar(*ptr++);
}
return(len);
}
int close(int file) {
return(-1);
}
caddr_t sbrk(int incr) {
extern char end; /* Defined by the linker */
static char *heap_end;
char *prev_heap_end;
if (heap_end == 0)
{
heap_end = &end;
}
prev_heap_end = heap_end;
if (heap_end + incr > stack_ptr)
{
_write (1, "Heap and stack collision\n", 25);
abort ();
}
heap_end += incr;
return((caddr_t) prev_heap_end);
}
int isatty(int file) {
return(1);
}
int fstat(int file, struct stat *st) {
st->st_mode = S_IFCHR;
return(0);
}
int stat(char *filename, struct stat *st) {
st->st_mode = S_IFCHR;
return(0);
}
int open(const char *path, int flags) {
return(0);
}
int _exit() {
SYSTRAP(RETURN);
}
int execve(char *name, char **argv, char **env) {
errno = ENOMEM;
return(-1);
}
int fork() {
errno = EAGAIN;
return(-1);
}
int getpid() {
return(1);
}
int kill(int pid, int sig) {
errno = EINVAL;
return(-1);
}
int link(char *old, char *new) {
errno = EMLINK;
return(-1);
}
clock_t times(struct tms *buf) {
return(-1);
}
int unlink(char *name) {
errno = ENOENT;
return(-1);
}
int wait(int *status) {
errno = ECHILD;
return(-1);
}
/* end of syscalls.c */
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