Small tweaks

Lots of new code imported.

src/lib9p/ramfs.c

@@ -0,0 +1,163 @@
+#include <u.h>
+#include <libc.h>
+#include <auth.h>
+#include <fcall.h>
+#include <thread.h>
+#include <9p.h>
+
+static char Ebad[] = "something bad happened";
+static char Enomem[] = "no memory";
+
+typedef struct Ramfile	Ramfile;
+struct Ramfile {
+	char *data;
+	int ndata;
+};
+
+void
+fsread(Req *r)
+{
+	Ramfile *rf;
+	vlong offset;
+	long count;
+
+	rf = r->fid->file->aux;
+	offset = r->ifcall.offset;
+	count = r->ifcall.count;
+
+//print("read %ld %lld\n", *count, offset);
+	if(offset >= rf->ndata){
+		r->ofcall.count = 0;
+		respond(r, nil);
+		return;
+	}
+
+	if(offset+count >= rf->ndata)
+		count = rf->ndata - offset;
+
+	memmove(r->ofcall.data, rf->data+offset, count);
+	r->ofcall.count = count;
+	respond(r, nil);
+}
+
+void
+fswrite(Req *r)
+{
+	void *v;
+	Ramfile *rf;
+	vlong offset;
+	long count;
+
+	rf = r->fid->file->aux;
+	offset = r->ifcall.offset;
+	count = r->ifcall.count;
+
+	if(offset+count >= rf->ndata){
+		v = realloc(rf->data, offset+count);
+		if(v == nil){
+			respond(r, Enomem);
+			return;
+		}
+		rf->data = v;
+		rf->ndata = offset+count;
+		r->fid->file->length = rf->ndata;
+	}
+	memmove(rf->data+offset, r->ifcall.data, count);
+	r->ofcall.count = count;
+	respond(r, nil);
+}
+
+void
+fscreate(Req *r)
+{
+	Ramfile *rf;
+	File *f;
+
+	if(f = createfile(r->fid->file, r->ifcall.name, r->fid->uid, r->ifcall.perm, nil)){
+		rf = emalloc9p(sizeof *rf);
+		f->aux = rf;
+		r->fid->file = f;
+		r->ofcall.qid = f->qid;
+		respond(r, nil);
+		return;
+	}
+	respond(r, Ebad);
+}
+
+void
+fsopen(Req *r)
+{
+	Ramfile *rf;
+
+	rf = r->fid->file->aux;
+
+	if(rf && (r->ifcall.mode&OTRUNC)){
+		rf->ndata = 0;
+		r->fid->file->length = 0;
+	}
+
+	respond(r, nil);
+}
+
+void
+fsdestroyfile(File *f)
+{
+	Ramfile *rf;
+
+//fprint(2, "clunk\n");
+	rf = f->aux;
+	if(rf){
+		free(rf->data);
+		free(rf);
+	}
+}
+
+Srv fs = {
+	.open=	fsopen,
+	.read=	fsread,
+	.write=	fswrite,
+	.create=	fscreate,
+};
+
+void
+usage(void)
+{
+	fprint(2, "usage: ramfs [-D] [-s srvname] [-m mtpt]\n");
+	exits("usage");
+}
+
+void
+main(int argc, char **argv)
+{
+	char *srvname = nil;
+	char *mtpt = nil;
+	Qid q;
+
+	fs.tree = alloctree(nil, nil, DMDIR|0777, fsdestroyfile);
+	q = fs.tree->root->qid;
+
+	ARGBEGIN{
+	case 'D':
+		chatty9p++;
+		break;
+	case 's':
+		srvname = EARGF(usage());
+		break;
+	case 'm':
+		mtpt = EARGF(usage());
+		break;
+	default:
+		usage();
+	}ARGEND;
+
+	if(argc)
+		usage();
+
+	if(chatty9p)
+		fprint(2, "ramsrv.nopipe %d srvname %s mtpt %s\n", fs.nopipe, srvname, mtpt);
+	if(srvname == nil && mtpt == nil)
+		sysfatal("you should at least specify a -s or -m option");
+
+	postmountsrv(&fs, srvname, mtpt, MREPL|MCREATE);
+	exits(0);
+}