20060303a

1 files changed, 186 insertions, 0 deletions

diff --git a/appl/cmd/fs/mergewrite.b b/appl/cmd/fs/mergewrite.b
new file mode 100644
index 00000000..3ff1b1f1
--- /dev/null
+++ b/appl/cmd/fs/mergewrite.b
@@ -0,0 +1,186 @@
+implement Fsmodule;
+include "sys.m";
+	sys: Sys;
+include "draw.m";
+include "sh.m";
+include "readdir.m";
+	readdir: Readdir;
+include "fslib.m";
+	fslib: Fslib;
+	Report, Value, quit, report: import fslib;
+	Fschan, Fsdata, Entrychan, Entry,
+	Cmpchan, Option,
+	Next, Down, Skip, Quit: import Fslib;
+
+types(): string
+{
+	return "vmsx";			# XXX bad argument ordering...
+}
+
+init()
+{
+	sys = load Sys Sys->PATH;
+	readdir = load Readdir Readdir->PATH;
+	if(readdir == nil){
+		sys->fprint(sys->fildes(2), "fs: mergewrite: cannot load %s: %r\n", Readdir->PATH);
+		raise "fail:bad module";
+	}
+	readdir->init(nil, 0);
+
+	fslib = load Fslib Fslib->PATH;
+	if(fslib == nil){
+		sys->fprint(sys->fildes(2), "fs: mergewrite: cannot load %s: %r\n", Fslib->PATH);
+		raise "fail:bad module";
+	}
+}
+
+run(nil: ref Draw->Context, report: ref Report,
+			nil: list of Option, args: list of ref Value): ref Value
+{
+	sync := chan of int;
+	spawn  fswriteproc(sync, (hd args).m().i, (hd tl args).s().i, (hd tl tl args).x().i, report.start("mergewrite"));
+	<-sync;
+	return ref Value.V(sync);
+}
+
+fswriteproc(sync: chan of int, cmp: Cmpchan, root: string, c: Fschan, errorc: chan of string)
+{
+	sys->pctl(Sys->FORKNS, nil);
+	sync <-= 1;
+	if(<-sync == 0){
+		(<-c).t1 <-= Quit;
+		quit(errorc);
+	}
+		
+	((d, nil), reply) := <-c;
+	if(root != nil){
+		d = ref *d;
+		d.name = root;
+	}
+	fswritedir(d.name, cmp, d, reply, c, errorc);
+	quit(errorc);
+}
+
+fswritedir(path: string, cmp: Cmpchan, dir: ref Sys->Dir, dreply: chan of int, c: Fschan, errorc: chan of string)
+{
+	fd: ref Sys->FD;
+	if(dir.mode & Sys->DMDIR){
+		fd = sys->create(dir.name, Sys->OREAD, dir.mode|8r300);
+		made := fd != nil;
+		if(fd == nil && (fd = sys->open(dir.name, Sys->OREAD)) == nil){
+			dreply <-= Next;
+			report(errorc, sys->sprint("cannot create %q, mode %uo: %r", path, dir.mode|8r300));
+			return;
+		}
+		# XXX if we haven't just made it, we should chmod the old entry u+w to enable writing.
+		if(sys->chdir(dir.name) == -1){		# XXX beware of names starting with '#'
+			dreply <-= Next;
+			report(errorc, sys->sprint("cannot cd to %q: %r", path));
+			fd = nil;
+			sys->remove(dir.name);
+			return;
+		}
+		dreply <-= Down;
+		entries: array of ref Sys->Dir;
+		if(made == 0)
+			entries = readdir->readall(fd, Readdir->NAME|Readdir->COMPACT).t0;
+		i := 0;
+		eod := 0;
+		d0, d1: ref Sys->Dir;
+		reply: chan of int;
+		path[len path] = '/';
+		for(;;){
+			if(!eod && d0 == nil){
+				((d0, nil), reply) = <-c;
+				if(d0 == nil){
+					reply <-= Next;
+					eod = 1;
+				}
+			}
+			if(d1 == nil && i < len entries)
+				d1 = entries[i++];
+			if(d0 == nil && d1 == nil)
+				break;
+
+			(wd0, wd1) := (d0, d1);
+			if(d0 != nil && d1 != nil && d0.name != d1.name){
+				if(d0.name < d1.name)
+					wd1 = nil;
+				else
+					wd0 = nil;
+			}
+			r := compare(cmp, wd0, wd1);
+			if(wd1 != nil && (r & 2r10) == 0){
+				if(wd1.mode & Sys->DMDIR)
+					rmdir(wd1.name);
+				else
+					remove(wd1.name);
+				d1 = nil;
+			}
+			if(wd0 != nil){
+				if((r & 2r01) == 0)
+					reply <-= Next;
+				else
+					fswritedir(path + wd0.name, cmp, d0, reply, c, errorc);
+				d0 = nil;
+			}
+		}
+		sys->chdir("..");
+		if((dir.mode & 8r300) != 8r300){
+			ws := Sys->nulldir;
+			ws.mode = dir.mode;
+			if(sys->fwstat(fd, ws) == -1)
+				report(errorc, sys->sprint("cannot wstat %q: %r", path));
+		}
+	}else{
+		fd = sys->create(dir.name, Sys->OWRITE, dir.mode);
+		if(fd == nil){
+			dreply <-= Next;
+			report(errorc, sys->sprint("cannot create %q, mode %uo: %r", path, dir.mode|8r300));
+			return;
+		}
+		dreply <-= Down;
+		while((((nil, buf), reply) := <-c).t0.data != nil){
+			nw := sys->write(fd, buf, len buf);
+			if(nw < len buf){
+				if(nw == -1)
+					errorc <-= sys->sprint("error writing %q: %r", path);
+				else
+					errorc <-= sys->sprint("short write");
+				reply <-= Skip;
+				break;
+			}
+			reply <-= Next;
+		}
+		reply <-= Next;
+	}
+}
+
+rmdir(name: string)
+{
+	(d, n) := readdir->init(name, Readdir->NONE|Readdir->COMPACT);
+	for(i := 0; i < n; i++){
+		path := name+"/"+d[i].name;
+		if(d[i].mode & Sys->DMDIR)
+			rmdir(path);
+		else
+			remove(path);
+	}
+	remove(name);
+}
+
+remove(name: string)
+{
+	if(sys->remove(name) < 0)
+		sys->fprint(sys->fildes(2), "mergewrite: cannot remove %q: %r\n", name);
+}
+
+compare(cmp: Cmpchan, d0, d1: ref Sys->Dir): int
+{
+	mask := (d0 != nil) | (d1 != nil) << 1;
+	if(cmp == nil)
+		return mask;
+	reply := chan of int;
+	cmp <-= (d0, d1, reply);
+	return <-reply & mask;
+}