Import sources from 2011-03-30 iso image

1 files changed, 357 insertions, 0 deletions

diff --git a/sys/src/9/port/devsrv.c b/sys/src/9/port/devsrv.c
new file mode 100755
index 000000000..161e77eed
--- /dev/null
+++ b/sys/src/9/port/devsrv.c
@@ -0,0 +1,357 @@
+#include	"u.h"
+#include	"../port/lib.h"
+#include	"mem.h"
+#include	"dat.h"
+#include	"fns.h"
+#include	"../port/error.h"
+
+
+typedef struct Srv Srv;
+struct Srv
+{
+	char	*name;
+	char	*owner;
+	ulong	perm;
+	Chan	*chan;
+	Srv	*link;
+	ulong	path;
+};
+
+static QLock	srvlk;
+static Srv	*srv;
+static int	qidpath;
+
+static int
+srvgen(Chan *c, char*, Dirtab*, int, int s, Dir *dp)
+{
+	Srv *sp;
+	Qid q;
+
+	if(s == DEVDOTDOT){
+		devdir(c, c->qid, "#s", 0, eve, 0555, dp);
+		return 1;
+	}
+
+	qlock(&srvlk);
+	for(sp = srv; sp && s; sp = sp->link)
+		s--;
+
+	if(sp == 0) {
+		qunlock(&srvlk);
+		return -1;
+	}
+
+	mkqid(&q, sp->path, 0, QTFILE);
+	/* make sure name string continues to exist after we release lock */
+	kstrcpy(up->genbuf, sp->name, sizeof up->genbuf);
+	devdir(c, q, up->genbuf, 0, sp->owner, sp->perm, dp);
+	qunlock(&srvlk);
+	return 1;
+}
+
+static void
+srvinit(void)
+{
+	qidpath = 1;
+}
+
+static Chan*
+srvattach(char *spec)
+{
+	return devattach('s', spec);
+}
+
+static Walkqid*
+srvwalk(Chan *c, Chan *nc, char **name, int nname)
+{
+	return devwalk(c, nc, name, nname, 0, 0, srvgen);
+}
+
+static Srv*
+srvlookup(char *name, ulong qidpath)
+{
+	Srv *sp;
+	for(sp = srv; sp; sp = sp->link)
+		if(sp->path == qidpath || (name && strcmp(sp->name, name) == 0))
+			return sp;
+	return nil;
+}
+
+static int
+srvstat(Chan *c, uchar *db, int n)
+{
+	return devstat(c, db, n, 0, 0, srvgen);
+}
+
+char*
+srvname(Chan *c)
+{
+	Srv *sp;
+	char *s;
+
+	for(sp = srv; sp; sp = sp->link)
+		if(sp->chan == c){
+			s = smalloc(3+strlen(sp->name)+1);
+			sprint(s, "#s/%s", sp->name);
+			return s;
+		}
+	return nil;
+}
+
+static Chan*
+srvopen(Chan *c, int omode)
+{
+	Srv *sp;
+
+	if(c->qid.type == QTDIR){
+		if(omode & ORCLOSE)
+			error(Eperm);
+		if(omode != OREAD)
+			error(Eisdir);
+		c->mode = omode;
+		c->flag |= COPEN;
+		c->offset = 0;
+		return c;
+	}
+	qlock(&srvlk);
+	if(waserror()){
+		qunlock(&srvlk);
+		nexterror();
+	}
+
+	sp = srvlookup(nil, c->qid.path);
+	if(sp == 0 || sp->chan == 0)
+		error(Eshutdown);
+
+	if(omode&OTRUNC)
+		error("srv file already exists");
+	if(openmode(omode)!=sp->chan->mode && sp->chan->mode!=ORDWR)
+		error(Eperm);
+	devpermcheck(sp->owner, sp->perm, omode);
+
+	cclose(c);
+	incref(sp->chan);
+	qunlock(&srvlk);
+	poperror();
+	return sp->chan;
+}
+
+static void
+srvcreate(Chan *c, char *name, int omode, ulong perm)
+{
+	char *sname;
+	Srv *sp;
+
+	if(openmode(omode) != OWRITE)
+		error(Eperm);
+
+	if(omode & OCEXEC)	/* can't happen */
+		panic("someone broke namec");
+
+	sp = smalloc(sizeof *sp);
+	sname = smalloc(strlen(name)+1);
+
+	qlock(&srvlk);
+	if(waserror()){
+		free(sp);
+		free(sname);
+		qunlock(&srvlk);
+		nexterror();
+	}
+	if(sp == nil || sname == nil)
+		error(Enomem);
+	if(srvlookup(name, -1))
+		error(Eexist);
+
+	sp->path = qidpath++;
+	sp->link = srv;
+	strcpy(sname, name);
+	sp->name = sname;
+	c->qid.type = QTFILE;
+	c->qid.path = sp->path;
+	srv = sp;
+	qunlock(&srvlk);
+	poperror();
+
+	kstrdup(&sp->owner, up->user);
+	sp->perm = perm&0777;
+
+	c->flag |= COPEN;
+	c->mode = OWRITE;
+}
+
+static void
+srvremove(Chan *c)
+{
+	Srv *sp, **l;
+
+	if(c->qid.type == QTDIR)
+		error(Eperm);
+
+	qlock(&srvlk);
+	if(waserror()){
+		qunlock(&srvlk);
+		nexterror();
+	}
+	l = &srv;
+	for(sp = *l; sp; sp = sp->link) {
+		if(sp->path == c->qid.path)
+			break;
+
+		l = &sp->link;
+	}
+	if(sp == 0)
+		error(Enonexist);
+
+	/*
+	 * Only eve can remove system services.
+	 * No one can remove #s/boot.
+	 */
+	if(strcmp(sp->owner, eve) == 0 && !iseve())
+		error(Eperm);
+	if(strcmp(sp->name, "boot") == 0)
+		error(Eperm);
+
+	/*
+	 * No removing personal services.
+	 */
+	if((sp->perm&7) != 7 && strcmp(sp->owner, up->user) && !iseve())
+		error(Eperm);
+
+	*l = sp->link;
+	qunlock(&srvlk);
+	poperror();
+
+	if(sp->chan)
+		cclose(sp->chan);
+	free(sp->owner);
+	free(sp->name);
+	free(sp);
+}
+
+static int
+srvwstat(Chan *c, uchar *dp, int n)
+{
+	char *strs;
+	Dir d;
+	Srv *sp;
+
+	if(c->qid.type & QTDIR)
+		error(Eperm);
+
+	strs = nil;
+	qlock(&srvlk);
+	if(waserror()){
+		qunlock(&srvlk);
+		free(strs);
+		nexterror();
+	}
+
+	sp = srvlookup(nil, c->qid.path);
+	if(sp == 0)
+		error(Enonexist);
+
+	if(strcmp(sp->owner, up->user) != 0 && !iseve())
+		error(Eperm);
+
+	strs = smalloc(n);
+	n = convM2D(dp, n, &d, strs);
+	if(n == 0)
+		error(Eshortstat);
+	if(d.mode != ~0UL)
+		sp->perm = d.mode & 0777;
+	if(d.uid && *d.uid)
+		kstrdup(&sp->owner, d.uid);
+	if(d.name && *d.name && strcmp(sp->name, d.name) != 0) {
+		if(strchr(d.name, '/') != nil)
+			error(Ebadchar);
+		kstrdup(&sp->name, d.name);
+	}
+	qunlock(&srvlk);
+	free(strs);
+	poperror();
+	return n;
+}
+
+static void
+srvclose(Chan *c)
+{
+	/*
+	 * in theory we need to override any changes in removability
+	 * since open, but since all that's checked is the owner,
+	 * which is immutable, all is well.
+	 */
+	if(c->flag & CRCLOSE){
+		if(waserror())
+			return;
+		srvremove(c);
+		poperror();
+	}
+}
+
+static long
+srvread(Chan *c, void *va, long n, vlong)
+{
+	isdir(c);
+	return devdirread(c, va, n, 0, 0, srvgen);
+}
+
+static long
+srvwrite(Chan *c, void *va, long n, vlong)
+{
+	Srv *sp;
+	Chan *c1;
+	int fd;
+	char buf[32];
+
+	if(n >= sizeof buf)
+		error(Egreg);
+	memmove(buf, va, n);	/* so we can NUL-terminate */
+	buf[n] = 0;
+	fd = strtoul(buf, 0, 0);
+
+	c1 = fdtochan(fd, -1, 0, 1);	/* error check and inc ref */
+
+	qlock(&srvlk);
+	if(waserror()) {
+		qunlock(&srvlk);
+		cclose(c1);
+		nexterror();
+	}
+	if(c1->flag & (CCEXEC|CRCLOSE))
+		error("posted fd has remove-on-close or close-on-exec");
+	if(c1->qid.type & QTAUTH)
+		error("cannot post auth file in srv");
+	sp = srvlookup(nil, c->qid.path);
+	if(sp == 0)
+		error(Enonexist);
+
+	if(sp->chan)
+		error(Ebadusefd);
+
+	sp->chan = c1;
+	qunlock(&srvlk);
+	poperror();
+	return n;
+}
+
+Dev srvdevtab = {
+	's',
+	"srv",
+
+	devreset,
+	srvinit,	
+	devshutdown,
+	srvattach,
+	srvwalk,
+	srvstat,
+	srvopen,
+	srvcreate,
+	srvclose,
+	srvread,
+	devbread,
+	srvwrite,
+	devbwrite,
+	srvremove,
+	srvwstat,
+};