base fs scaffolding in place.

2 files changed, 347 insertions, 0 deletions

diff --git a/fs.c b/fs.c
new file mode 100644
index 0000000..65fa705
--- /dev/null
+++ b/fs.c
@@ -0,0 +1,336 @@
+#include <u.h>
+#include <libc.h>
+#include <auth.h>
+#include <thread.h>
+#include <draw.h>
+#include <memdraw.h>
+#include <fcall.h>
+#include <9p.h>
+
+typedef struct Dirtab Dirtab;
+
+struct Dirtab
+{
+	char *name;
+	uchar type;
+	uint qidpath;
+	uint perm;
+};
+
+enum {
+	Qroot,
+	Qctl,
+	Qframe,
+};
+
+char Ebotch[] = "9P protocol botch";
+char Enotfound[] = "file not found";
+char Enotdir[] = "not a directory";
+char Eperm[] = "permission denied";
+
+Dirtab dirtab[] = {
+	"/",		QTDIR,	Qroot,	0555|DMDIR,
+	"ctl",		QTFILE,	Qctl,	0600,
+	"frame",	QTFILE,	Qframe,	0444,
+};
+char *jefe = "Pablo R. Picasso";
+Memimage *fb;
+
+static int
+mode2perm(int m)
+{
+	static int perms[4] = {4, 2, 6, 1};
+
+	return perms[m&OMASK];
+}
+
+static void
+fillstat(Dir *dir, Dirtab *d)
+{
+	dir->name = estrdup9p(d->name);
+	dir->uid = estrdup9p(jefe);
+	dir->gid = estrdup9p(jefe);
+	dir->mode = d->perm;
+	dir->length = 0;
+	dir->qid = (Qid){d->qidpath, 0, d->type};
+	dir->atime = time(0);
+	dir->mtime = time(0);
+	dir->muid = estrdup9p("");
+}
+
+static int
+dirgen(int n, Dir *dir, void*)
+{
+	if(++n >= nelem(dirtab))
+		return -1;
+	fillstat(dir, &dirtab[n]);
+	return 0;
+}
+
+static int
+readimg(Memimage *i, char *t, Rectangle r, int offset, int n)
+{
+	int ww, oo, y, m;
+	uchar *tt;
+
+	ww = bytesperline(r, i->depth);
+	r.min.y += offset/ww;
+	if(r.min.y >= r.max.y)
+		return 0;
+
+	y = r.min.y + (n + ww-1)/ww;
+	if(y < r.max.y)
+		r.max.y = y;
+
+	m = ww * Dy(r);
+	oo = offset % ww;
+	if(oo == 0 && n >= m)
+		return unloadmemimage(i, r, (uchar*)t, n);
+
+	if((tt = malloc(m)) == nil)
+		return -1;
+
+	m = unloadmemimage(i, r, tt, m) - oo;
+	if(m > 0){
+		if(n < m) m = n;
+		memmove(t, tt + oo, m);
+	}
+
+	free(tt);
+	return m;
+}
+
+void
+fsattach(Req *r)
+{
+	if(r->ifcall.aname && r->ifcall.aname[0]){
+		respond(r, "invalid attach specifier");
+		return;
+	}
+
+	r->ofcall.qid = (Qid){Qroot, 0, QTDIR};
+	r->fid->qid = r->ofcall.qid;
+	r->fid->aux = nil;
+	respond(r, nil);
+}
+
+void
+fsopen(Req *r)
+{
+	int i, perm, want;
+
+	for(i = 0; i < nelem(dirtab); i++)
+		if(r->fid->qid.path == dirtab[i].qidpath)
+			break;
+
+	if(i < nelem(dirtab)){
+		if(strcmp(r->fid->uid, jefe) == 0)
+			perm = dirtab[i].perm>>6;
+		else
+			perm = dirtab[i].perm;
+	}else{
+		respond(r, Ebotch);
+		return;
+	};
+
+	if((r->ifcall.mode & (OTRUNC|OCEXEC|ORCLOSE)) != 0)
+		goto deny;
+	want = mode2perm(r->ifcall.mode);
+	if((want & perm) != want){
+deny:
+		respond(r, Eperm);
+		return;
+	}
+	respond(r, nil);
+}
+
+void
+fsread(Req *r)
+{
+	Memimage *i;
+	char buf[128], cbuf[30], *t;
+	ulong off, cnt;
+	int n;
+
+	off = r->ifcall.offset;
+	cnt = r->ifcall.count;
+
+	switch(r->fid->qid.path){
+	default:
+		respond(r, "bug in fsread");
+		break;
+	case Qroot:
+		dirread9p(r, dirgen, nil);
+		respond(r, nil);
+		break;
+	case Qctl:
+		respond(r, nil);
+		break;
+	case Qframe:
+		i = fb;
+		if(off < 5*12){
+			n = snprint(buf, sizeof buf, "%11s %11d %11d %11d %11d ",
+				chantostr(cbuf, i->chan),
+				i->r.min.x, i->r.min.y, i->r.max.x, i->r.max.y);
+			t = estrdup9p(buf);
+
+			if(off > n){
+				off = n;
+				cnt = 0;
+			}
+
+			if(off+cnt > n)
+				cnt = n-off;
+
+			r->ofcall.data = t+off;
+			r->ofcall.count = cnt;
+			respond(r, nil);
+			free(t);
+			break;
+		}
+
+		off -= 5*12;
+		n = -1;
+		t = malloc(cnt);
+		if(t != nil){
+			r->ofcall.data = t;
+			n = readimg(i, t, i->r, off, cnt);
+		}
+
+		if(n < 0){
+			buf[0] = 0;
+			errstr(buf, sizeof buf);
+			respond(r, buf);
+		}else{
+			r->ofcall.count = n;
+			respond(r, nil);
+		}
+		free(t);
+		break;
+	}
+}
+
+void
+fswrite(Req *r)
+{
+	char *msg, *f[10];
+	ulong cnt, nf;
+	int i;
+
+	cnt = r->ifcall.count;
+
+	switch(r->fid->qid.path){
+	default:
+		respond(r, "bug in fswrite");
+		break;
+	case Qctl:
+		msg = emalloc9p(cnt+1);
+		memmove(msg, r->ifcall.data, cnt);
+		msg[cnt] = 0;
+		nf = tokenize(msg, f, nelem(f));
+		for(i = 0; i < nf; i++)
+			fprint(2, "%s[%d]%s%s", i == 0? "": " ", i, f[i], i == nf-1? "\n": "");
+		free(msg);
+		r->ofcall.count = cnt;
+		respond(r, nil);
+		break;
+	}
+}
+
+void
+fsstat(Req *r)
+{
+	int i;
+
+	for(i = 0; i < nelem(dirtab); i++)
+		if(r->fid->qid.path == dirtab[i].qidpath){
+			fillstat(&r->d, &dirtab[i]);
+			respond(r, nil);
+			return;
+		}
+	respond(r, Enotfound);	
+}
+
+char *
+fswalk1(Fid *f, char *name, Qid *qid)
+{
+	int i;
+
+	switch(f->qid.path){
+	case Qroot:
+		if(strcmp(name, "..") == 0){
+			*qid = f->qid;
+			return nil;
+		}
+		for(i = 1; i < nelem(dirtab); i++)
+			if(strcmp(name, dirtab[i].name) == 0){
+				*qid = (Qid){dirtab[i].qidpath, 0, 0};
+				f->qid = *qid;
+				return nil;
+			}
+		return Enotfound;
+	default:
+		return Enotdir;
+	}
+}
+
+char *
+fsclone(Fid *old, Fid *new)
+{
+	USED(old, new);
+	return nil;
+}
+
+Srv fs = {
+	.attach	= fsattach,
+	.open	= fsopen,
+	.read	= fsread,
+	.write	= fswrite,
+	.stat	= fsstat,
+	.walk1	= fswalk1,
+	.clone	= fsclone,
+};
+
+void
+usage(void)
+{
+	fprint(2, "usage: %s [-D] [-s srvname] [-m mtpt]\n", argv0);
+	exits("usage");
+}
+
+void
+threadmain(int argc, char *argv[])
+{
+	char *srvname, *mtpt;
+	int fd;
+
+	srvname = "render";
+	mtpt = "/mnt/render";
+	ARGBEGIN{
+	case 'D':
+		chatty9p++;
+		break;
+	case 's':
+		srvname = EARGF(usage());
+		break;
+	case 'm':
+		mtpt = EARGF(usage());
+		break;
+	default: usage();
+	}ARGEND
+	if(argc != 0)
+		usage();
+
+	jefe = getuser();
+
+	fd = open("/dev/window", OREAD);
+	if(fd < 0)
+		sysfatal("open: %r");
+	fb = readmemimage(fd);
+	if(fb == nil)
+		sysfatal("readmemimage: %r");
+	close(fd);
+
+	threadpostmountsrv(&fs, srvname, mtpt, MREPL|MCREATE);
+	exits(nil);
+}
diff --git a/mkfile b/mkfile
new file mode 100644
index 0000000..7cc25cc
--- /dev/null
+++ b/mkfile
@@ -0,0 +1,11 @@
+</$objtype/mkfile
+
+BIN=/$objtype/bin
+TARG=renderfs
+OFILES=\
+	fs.$O\
+
+</sys/src/cmd/mkone
+
+uninstall:V:
+	rm -f $BIN/$TARG