add hgfs, a mercurial filesystem

1 files changed, 97 insertions, 0 deletions

diff --git a/sys/src/cmd/hgfs/zip.c b/sys/src/cmd/hgfs/zip.c
new file mode 100644
index 000000000..31ab65f64
--- /dev/null
+++ b/sys/src/cmd/hgfs/zip.c
@@ -0,0 +1,97 @@
+#include <u.h>
+#include <libc.h>
+#include <thread.h>
+#include "dat.h"
+#include "fns.h"
+
+#include <flate.h>
+
+struct zbuf {
+	int	fd;
+	int	len;
+
+	uchar	*b, *p, *e;
+};
+
+static int
+zwrite(void *a, void *p, int n)
+{
+	int *ofd = a;
+
+	if(write(*ofd, p, n) != n)
+		return -1;
+	return n;
+}
+
+static int
+zgetc(void *a)
+{
+	struct zbuf *z = a;
+	int n;
+
+	for(;;){
+		if(z->p < z->e)
+			return *z->p++;
+		if(z->len <= 0)
+			return -1;
+		if((n = BUFSZ) > z->len)
+			n = z->len;
+		if((n = read(z->fd, z->p = z->b, n)) <= 0)
+			return -1;
+		z->len -= n;
+		z->e = z->p + n;
+	}
+}
+
+int
+funzip(int ofd, int zfd, int len)
+{
+	uchar buf[BUFSZ];
+	struct zbuf z;
+	int wlen, n;
+	uchar *p;
+
+	if(len == 0)
+		return 0;
+
+	wlen = 0;
+	if((n = BUFSZ) > len)
+		n = len;
+	if((n = read(zfd, p = buf, n)) <= 0)
+		return -1;
+	len -= n;
+	switch(*p){
+	default:
+		return -1;
+	case 'u':
+		p++;
+		n--;
+		/* no break */
+	case '\0':
+		while((n > 0) && (write(ofd, p, n) == n)){
+			wlen += n;
+			if(len <= 0)
+				break;
+			if((n = BUFSZ) > len)
+				n = len;
+			if((n = read(zfd, p = buf, n)) <= 0)
+				break;
+			len -= n;
+		}
+		break;
+	case 'x':
+		if(n < 2)
+			return -1;
+		z.fd = zfd;
+		z.len = len;
+		z.b = buf;
+		z.p = p + 2;
+		z.e = p + n;
+		if((wlen = inflate(&ofd, zwrite, &z, zgetc)) < 0){
+			werrstr("%s", flateerr(wlen));
+			return -1;
+		}
+		break;
+	}
+	return wlen;
+}