2 files changed, 111 insertions(+), 1 deletions(-)

A fs.c
M lc3.c

@@ 0,0 1,94 @@
+#include <fcall.h>
+#include <9p.h>
+
+char *mtpt = nil;
+Channel* clk;
+
+enum {
+	Lclk,
+	Lpc,
+};
+
+typedef struct Lfid Lfid;
+struct Lfid {
+	int type;
+};
+
+Lfid
+*lfidgen(int type)
+{
+	struct Lfid *lfid;
+	lfid = emalloc9p(sizeof *lfid);
+	lfid->type = type;
+	return lfid;
+}
+
+static void
+fsstart(Srv*)
+{
+	if(mtpt != nil) unmount(nil, mtpt);
+}
+
+static void
+fsend(Srv*)
+{
+	postnote(PNGROUP, getpid(), "shutdown");
+	exits(nil);
+}
+
+static void
+fsopen(Req *r)
+{
+	respond(r, nil);
+	return;
+}
+
+static void
+fsread(Req *r)
+{
+	Lfid *l = r->fid->file->aux;
+	switch(l->type){
+	case Lclk:
+		sendul(clk, (ulong) 1);
+		readstr(r, "");
+		break;
+	case Lpc:
+		readstr(r, smprint("%x\n",reg[R_PC]));
+		break;
+	}
+	respond(r, nil);
+	return;
+}
+
+static void
+fswrite(Req *r)
+{
+	int n;
+	char *argv;
+	n = r->ofcall.count = r->ifcall.count;
+	argv = emalloc9p(n+1);
+	memmove(argv, r->ifcall.data, n);
+	sendul(clk, strtoul(argv, 0, 10));
+	respond(r, nil);
+	return;
+}
+
+Srv fs = {
+	.start = fsstart,
+	.end = fsend,
+	.read = fsread,
+	.open = fsopen,
+	.write = fswrite,
+};
+
+void
+newfs(void)
+{
+	Tree *tree;
+	clk = chancreate(sizeof(ulong), 20);
+	tree = alloctree(nil, nil, DMDIR|0555, nil);
+	fs.tree = tree;
+	createfile(tree->root, "clk", nil, 0644, lfidgen(Lclk));
+	createfile(tree->root, "pc", nil, 0644, lfidgen(Lpc));
+	threadpostmountsrv(&fs, "lc3fs", mtpt, MREPL | MCREATE);
+}

@@ 2,8 2,10 @@
 #include <u.h>
 #include <libc.h>
 #include <stdio.h>
+#include <thread.h>
 #include "lc3.h"
 #include "util.c"
+#include "fs.c"
 
 int debug = 0;
 int consctl;


@@ 219,8 221,9 @@ op_trap(u16int in)
 }
 
 void
-main(int argc, char* argv[])
+threadmain(int argc, char* argv[])
 {
+	ulong steps = 0;
 	char *imagefile;
 	ARGBEGIN {
 	case 'd':


@@ 231,8 234,16 @@ main(int argc, char* argv[])
 		if(!readimage(imagefile)) {
 			exits("Could not read image file");
 		}
+		break;
+	case 'm':
+		mtpt = EARGF(usage());
+		break;
 	} ARGEND;
 
+	if(mtpt){
+		newfs();
+	}
+
 	consctl = open("/dev/consctl", OWRITE);
 	if(consctl == -1) exits("can't open /dev/consctl: %r\n");	// exactly one cond flag should be set at all times
 	reg[R_COND] = FL_ZRO;


@@ 241,6 252,9 @@ main(int argc, char* argv[])
 	int running = 1;
 	while (running)
 	{
+		print("%d\n", (int) steps);
+		if(mtpt && steps == 0)
+			steps += recvul(clk);
 		// fetch instruction
 		u16int instr = memread(reg[R_PC]++);
 		u16int op = instr >> 12;


@@ 307,6 321,8 @@ main(int argc, char* argv[])
 				print("%04x ", memory[i]);
 			print("\n");
 		}
+		if(mtpt && steps > 0)
+			steps--;
 	}
 	exits(nil);
 }