rdb.c

著名操作系统Plan 9的第三版的部分核心源代码。现在很难找到了。Plan 9是bell实验室开发的Unix后继者。

#include "u.h"
#include "../port/lib.h"
#include "mem.h"
#include "dat.h"
#include "fns.h"
#include "io.h"
#include "ureg.h"

extern Queue *printq;

#define DBG	if(0)scrprint
#pragma varargck argpos scrprint 1
static Ureg ureg;

static void
scrprint(char *fmt, ...)
{
	char buf[128];
	va_list va;
	int n;

	va_start(va, fmt);
	n = doprint(buf, buf+sizeof buf, fmt, va)-buf;
	va_end(va);
	putstrn(buf, n);
}

static char*
getline(void)
{
	static char buf[128];
	int i, c;

	for(;;){
		for(i=0; i<nelem(buf) && (c=serialgetc()) != '\n'; i++){
			DBG("%c...", c);
			buf[i] = c;
		}

		if(i < nelem(buf)){
			buf[i] = 0;
			return buf;
		}
	}
}

static void*
addr(char *s, Ureg *ureg)
{
	ulong a;

	a = strtoul(s, 0, 16);
	if(a < sizeof(Ureg))
		return ((uchar*)ureg)+a;
	return (void*)a;
}

static void
talkrdb(Ureg *ureg)
{
	uchar *a;
	char *req;

	printq = nil;	// turn off serial console
//	scrprint("Plan 9 debugger\n");
	iprint("Edebugger reset\n");
	for(;;){
		req = getline();
		switch(*req){
		case 'r':
			a = addr(req+1, ureg);
			DBG("read %p\n", a);
			iprint("R%.8lux %.2ux %.2ux %.2ux %.2ux\n", strtoul(req+1, 0, 16), a[0], a[1], a[2], a[3]);
			break;
/*
 *		case Tmput:
			n = min[4];
			if(n > 4){
				mesg(Rerr, Ecount);
				break;
			}
			a = addr(min+0);
			scrprint("mput %.8lux\n", a);
			memmove(a, min+5, n);
			mesg(Rmput, mout);
			break;
 *
 */
		default:
			DBG("unknown %c\n", *req);
			iprint("Eunknown message\n");
			break;
		}
	}
}

void
rdb(void)
{
	splhi();
	iprint("rdb...");
	callwithureg(talkrdb);
}