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/*
* Copyright (C) Paul Mackerras 1997.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*/
#include <stdarg.h>
int (*prom)();
void *chosen_handle;
void *stdin;
void *stdout;
void *stderr;
void exit(void);
void *finddevice(const char *name);
int getprop(void *phandle, const char *name, void *buf, int buflen);
void printk(char *fmt, ...);
void
start(int a1, int a2, void *promptr)
{
prom = (int (*)()) promptr;
chosen_handle = finddevice("/chosen");
if (chosen_handle == (void *) -1)
exit();
if (getprop(chosen_handle, "stdout", &stdout, sizeof(stdout)) != 4)
exit();
stderr = stdout;
if (getprop(chosen_handle, "stdin", &stdin, sizeof(stdin)) != 4)
exit();
boot(a1, a2, promptr);
for (;;)
exit();
}
int
write(void *handle, void *ptr, int nb)
{
struct prom_args {
char *service;
int nargs;
int nret;
void *ihandle;
void *addr;
int len;
int actual;
} args;
args.service = "write";
args.nargs = 3;
args.nret = 1;
args.ihandle = handle;
args.addr = ptr;
args.len = nb;
args.actual = -1;
(*prom)(&args);
return args.actual;
}
int writestring(void *f, char *ptr, int nb)
{
int w = 0, i;
char *ret = "\r";
for (i = 0; i < nb; ++i) {
if (ptr[i] == '\n') {
if (i > w) {
write(f, ptr + w, i - w);
w = i;
}
write(f, ret, 1);
}
}
if (w < nb)
write(f, ptr + w, nb - w);
return nb;
}
int
read(void *handle, void *ptr, int nb)
{
struct prom_args {
char *service;
int nargs;
int nret;
void *ihandle;
void *addr;
int len;
int actual;
} args;
args.service = "read";
args.nargs = 3;
args.nret = 1;
args.ihandle = handle;
args.addr = ptr;
args.len = nb;
args.actual = -1;
(*prom)(&args);
return args.actual;
}
void
exit()
{
struct prom_args {
char *service;
} args;
for (;;) {
args.service = "exit";
(*prom)(&args);
}
}
void
pause()
{
struct prom_args {
char *service;
} args;
args.service = "enter";
(*prom)(&args);
}
void *
finddevice(const char *name)
{
struct prom_args {
char *service;
int nargs;
int nret;
const char *devspec;
void *phandle;
} args;
args.service = "finddevice";
args.nargs = 1;
args.nret = 1;
args.devspec = name;
args.phandle = (void *) -1;
(*prom)(&args);
return args.phandle;
}
void *
claim(unsigned int virt, unsigned int size, unsigned int align)
{
struct prom_args {
char *service;
int nargs;
int nret;
unsigned int virt;
unsigned int size;
unsigned int align;
void *ret;
} args;
args.service = "claim";
args.nargs = 3;
args.nret = 1;
args.virt = virt;
args.size = size;
args.align = align;
(*prom)(&args);
return args.ret;
}
int
getprop(void *phandle, const char *name, void *buf, int buflen)
{
struct prom_args {
char *service;
int nargs;
int nret;
void *phandle;
const char *name;
void *buf;
int buflen;
int size;
} args;
args.service = "getprop";
args.nargs = 4;
args.nret = 1;
args.phandle = phandle;
args.name = name;
args.buf = buf;
args.buflen = buflen;
args.size = -1;
(*prom)(&args);
return args.size;
}
int
putc(int c, void *f)
{
char ch = c;
return writestring(f, &ch, 1) == 1? c: -1;
}
int
putchar(int c)
{
return putc(c, stdout);
}
int
fputs(char *str, void *f)
{
int n = strlen(str);
return writestring(f, str, n) == n? 0: -1;
}
int
readchar()
{
char ch;
for (;;) {
switch (read(stdin, &ch, 1)) {
case 1:
return ch;
case -1:
printk("read(stdin) returned -1\n");
return -1;
}
}
}
static char line[256];
static char *lineptr;
static int lineleft;
int
getchar()
{
int c;
if (lineleft == 0) {
lineptr = line;
for (;;) {
c = readchar();
if (c == -1 || c == 4)
break;
if (c == '\r' || c == '\n') {
*lineptr++ = '\n';
putchar('\n');
break;
}
switch (c) {
case 0177:
case '\b':
if (lineptr > line) {
putchar('\b');
putchar(' ');
putchar('\b');
--lineptr;
}
break;
case 'U' & 0x1F:
while (lineptr > line) {
putchar('\b');
putchar(' ');
putchar('\b');
--lineptr;
}
break;
default:
if (lineptr >= &line[sizeof(line) - 1])
putchar('\a');
else {
putchar(c);
*lineptr++ = c;
}
}
}
lineleft = lineptr - line;
lineptr = line;
}
if (lineleft == 0)
return -1;
--lineleft;
return *lineptr++;
}
extern int vsprintf(char *buf, const char *fmt, va_list args);
static char sprint_buf[1024];
void
printk(char *fmt, ...)
{
va_list args;
int n;
va_start(args, fmt);
n = vsprintf(sprint_buf, fmt, args);
va_end(args);
writestring(stdout, sprint_buf, n);
}
int
printf(char *fmt, ...)
{
va_list args;
int n;
va_start(args, fmt);
n = vsprintf(sprint_buf, fmt, args);
va_end(args);
writestring(stdout, sprint_buf, n);
return n;
}
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