git: got git?

Add a snapshot of git9 to 9front.

1 files changed, 67 insertions, 0 deletions

diff --git a/sys/src/cmd/git/objset.c b/sys/src/cmd/git/objset.c
new file mode 100644
index 000000000..d0c656c53
--- /dev/null
+++ b/sys/src/cmd/git/objset.c
@@ -0,0 +1,67 @@
+#include <u.h>
+#include <libc.h>
+
+#include "git.h"
+
+void
+osinit(Objset *s)
+{
+	s->sz = 16;
+	s->nobj = 0;
+	s->obj = eamalloc(s->sz, sizeof(Hash));
+}
+
+void
+osclear(Objset *s)
+{
+	free(s->obj);
+}
+
+void
+osadd(Objset *s, Object *o)
+{
+	u32int probe;
+	Object **obj;
+	int i, sz;
+
+	probe = GETBE32(o->hash.h) % s->sz;
+	while(s->obj[probe]){
+		if(hasheq(&s->obj[probe]->hash, &o->hash)){
+			s->obj[probe] = o;
+			return;
+		}
+		probe = (probe + 1) % s->sz;
+	}
+	assert(s->obj[probe] == nil);
+	s->obj[probe] = o;
+	s->nobj++;
+	if(s->sz < 2*s->nobj){
+		sz = s->sz;
+		obj = s->obj;
+
+		s->sz *= 2;
+		s->nobj = 0;
+		s->obj = eamalloc(s->sz, sizeof(Hash));
+		for(i = 0; i < sz; i++)
+			if(obj[i])
+				osadd(s, obj[i]);
+		free(obj);
+	}
+}
+
+Object*
+osfind(Objset *s, Hash h)
+{
+	u32int probe;
+
+	for(probe = GETBE32(h.h) % s->sz; s->obj[probe]; probe = (probe + 1) % s->sz)
+		if(hasheq(&s->obj[probe]->hash, &h))
+			return s->obj[probe]; 
+	return 0;
+}
+
+int
+oshas(Objset *s, Hash h)
+{
+	return osfind(s, h) != nil;
+}