add hgfs, a mercurial filesystem

1 files changed, 69 insertions, 0 deletions

diff --git a/sys/src/cmd/hgfs/hash.c b/sys/src/cmd/hgfs/hash.c
new file mode 100644
index 000000000..768e35759
--- /dev/null
+++ b/sys/src/cmd/hgfs/hash.c
@@ -0,0 +1,69 @@
+#include <u.h>
+#include <libc.h>
+#include <thread.h>
+#include "dat.h"
+#include "fns.h"
+
+#include <mp.h>
+#include <libsec.h>
+
+int
+Hfmt(Fmt *f)
+{
+	uchar *p;
+
+	p = va_arg(f->args, uchar*);
+	return fmtprint(f, 
+		"%.2x%.2x%.2x%.2x%.2x%.2x",
+		p[0], p[1], p[2], p[3], p[4], p[5]);
+}
+
+int
+fhash(int fd, uchar p1[], uchar p2[], uchar h[])
+{
+	DigestState *ds;
+	uchar buf[BUFSZ];
+	int n;
+
+	ds = nil;
+	memset(h, 0, HASHSZ);
+	if(memcmp(p1, p2, HASHSZ) > 0){
+		ds = sha1(p2, HASHSZ, nil, ds);
+		sha1(p1, HASHSZ, nil, ds);
+	} else {
+		ds = sha1(p1, HASHSZ, nil, ds);
+		sha1(p2, HASHSZ, nil, ds);
+	}
+	while((n = read(fd, buf, BUFSZ)) > 0)
+		sha1(buf, n, nil, ds);
+	sha1(buf, 0, h, ds);
+
+	return 0;
+}
+
+int
+strhash(char *s, uchar *h)
+{
+	uchar *b;
+	int n;
+
+	b = h;
+	memset(h, 0, HASHSZ);
+	n = HASHSZ*2;
+	while(*s && n > 0){
+		if(*s >= '0' && *s <= '9')
+			*h |= *s - '0';
+		else if(*s >= 'a' && *s <= 'f')
+			*h |= 10 + *s - 'a';
+		else if(*s >= 'A' && *s <= 'F')
+			*h |= 10 + *s - 'A';
+		else
+			break;
+		if(n-- & 1)
+			h++;
+		else
+			*h <<= 4;
+		s++;
+	}
+	return h - b;
+}