20060303a

1 files changed, 72 insertions, 0 deletions

diff --git a/appl/spree/lib/base64.b b/appl/spree/lib/base64.b
new file mode 100644
index 00000000..c8381467
--- /dev/null
+++ b/appl/spree/lib/base64.b
@@ -0,0 +1,72 @@
+implement Base64;
+include "base64.m";
+
+PADCH: con '=';
+encode(b: array of byte): string
+{
+	chmap := "ABCDEFGHIJKLMNOPQRSTUVWXYZ" +
+			"abcdefghijklmnopqrstuvwxyz0123456789+/";
+	r := "";
+	blen := len b;
+	full := (blen + 2)/ 3;
+	rplen := (4*blen + 2) / 3;
+	ip := 0;
+	rp := 0;
+	for (i:=0; i<full; i++) {
+		word := 0;
+		for (j:=2; j>=0; j--)
+			if (ip < blen)
+				word = word | int b[ip++] << 8*j;
+		for (l:=3; l>=0; l--)
+			if (rp < rplen)
+				r[rp++] = chmap[(word >> (6*l)) & 16r3f];
+			else
+				r[rp++] = PADCH;
+	}
+	return r;
+}
+
+# Decode a base 64 string to a byte stream
+# Must be a multiple of 4 characters in length
+decode(s: string): array of byte
+{
+
+	tch: int;
+	slen := len s;
+	rlen := (3*slen+3)/4;
+	if (slen >= 4 && s[slen-1] == PADCH)
+		rlen--;
+	if (slen >= 4 && s[slen-2] == PADCH)
+		rlen--;
+	r := array[rlen] of byte;
+	full := slen / 4;
+	sp := 0;
+	rp := 0;
+	for (i:=0; i<full; i++) {
+		word := 0; 
+		for (j:=0; j<4; j++) {
+			ch := s[sp++];
+			case ch {
+			'A' to 'Z' =>
+				tch = ch - 'A';
+			'a' to 'z' =>
+				tch = ch - 'a' + 26;
+			'0' to '9' =>
+				tch = ch - '0' + 52;
+			'+' =>
+				tch = 62;
+			'/' =>
+				tch = 63;
+			* =>
+				tch = 0;
+			}
+			word = (word << 6) | tch;
+		}
+		for (l:=2; l>=0; l--)
+			if (rp < rlen)
+				r[rp++] = byte( (word >> 8*l) & 16rff);
+
+	}
+	return r;
+}
+