From 3efd7d9cfbd330ebb45f39648ee96a3e429a06f9 Mon Sep 17 00:00:00 2001
From: Bruce Hill <bruce@bruce-hill.com>
Date: Mon, 7 Apr 2025 18:14:20 -0400
Subject: Move core libraries into their own folder

---
 lib/base64/README.md |  3 ++
 lib/base64/base64.tm | 96 ++++++++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 99 insertions(+)
 create mode 100644 lib/base64/README.md
 create mode 100644 lib/base64/base64.tm

(limited to 'lib/base64')

diff --git a/lib/base64/README.md b/lib/base64/README.md
new file mode 100644
index 00000000..8db0f8ec
--- /dev/null
+++ b/lib/base64/README.md
@@ -0,0 +1,3 @@
+# Base64
+
+This is a library for encoding/decoding Base64 values.
diff --git a/lib/base64/base64.tm b/lib/base64/base64.tm
new file mode 100644
index 00000000..bf512a83
--- /dev/null
+++ b/lib/base64/base64.tm
@@ -0,0 +1,96 @@
+# Base 64 encoding and decoding
+
+_enc := "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/".bytes()
+
+_EQUAL_BYTE := Byte(0x3D)
+
+_dec : [Byte] = [
+    255, 255, 255, 255, 255, 255, 255, 255,
+    255, 255, 255, 255, 255, 255, 255, 255,
+    255, 255, 255, 255, 255, 255, 255, 255,
+    255, 255, 255, 255, 255, 255, 255, 255,
+    255, 255, 255, 255, 255, 255, 255, 255,
+    255, 255, 255, 62,  255, 255, 255, 63,
+    52,  53,  54,  55,  56,  57,  58,  59,
+    60,  61,  255, 255, 255, 255, 255, 255,
+    255, 0,   1,   2,   3,   4,   5,   6,
+    7,   8,   9,   10,  11,  12,  13,  14,
+    15,  16,  17,  18,  19,  20,  21,  22,
+    23,  24,  25,  255, 255, 255, 255, 255,
+    255, 26,  27,  28,  29,  30,  31,  32,
+    33,  34,  35,  36,  37,  38,  39,  40,
+    41,  42,  43,  44,  45,  46,  47,  48,
+    49,  50,  51,  255, 255, 255, 255, 255,
+]
+
+lang Base64
+    func parse(text:Text -> Base64?)
+        return Base64.from_bytes(text.bytes())
+
+    func from_bytes(bytes:[Byte] -> Base64?)
+        output := &[Byte(0) for _ in bytes.length * 4 / 3 + 4]
+        src := Int64(1)
+        dest := Int64(1)
+        while src + 2 <= Int64(bytes.length)
+            chunk24 := (
+                (Int32(bytes[src]) <<< 16) or (Int32(bytes[src+1]) <<< 8) or Int32(bytes[src+2])
+            )
+            src += 3
+
+            output[dest]   = _enc[1 + ((chunk24 >>> 18) and 0b111111)]
+            output[dest+1] = _enc[1 + ((chunk24 >>> 12) and 0b111111)]
+            output[dest+2] = _enc[1 + ((chunk24 >>> 6) and 0b111111)]
+            output[dest+3] = _enc[1 + (chunk24 and 0b111111)]
+            dest += 4
+
+        if src + 1 == bytes.length
+            chunk16 := (
+                (Int32(bytes[src]) <<< 8) or Int32(bytes[src+1])
+            )
+            output[dest]   = _enc[1 + ((chunk16 >>> 10) and 0b11111)]
+            output[dest+1] = _enc[1 + ((chunk16 >>> 4) and 0b111111)]
+            output[dest+2] = _enc[1 + ((chunk16 <<< 2)and 0b111111)]
+            output[dest+3] = _EQUAL_BYTE
+        else if src == bytes.length
+            chunk8 := Int32(bytes[src])
+            output[dest]   = _enc[1 + ((chunk8 >>> 2) and 0b111111)]
+            output[dest+1] = _enc[1 + ((chunk8 <<< 4) and 0b111111)]
+            output[dest+2] = _EQUAL_BYTE
+            output[dest+3] = _EQUAL_BYTE
+
+        return Base64.from_text(Text.from_bytes(output[]) or return none)
+
+    func decode_text(b64:Base64 -> Text?)
+        return Text.from_bytes(b64.decode_bytes() or return none)
+
+    func decode_bytes(b64:Base64 -> [Byte]?)
+        bytes := b64.text.bytes()
+        output := &[Byte(0) for _ in bytes.length/4 * 3]
+        src := Int64(1)
+        dest := Int64(1)
+        while src + 3 <= Int64(bytes.length)
+            chunk24 := (
+                (Int32(_dec[1+bytes[src]]) <<< 18) or
+                (Int32(_dec[1+bytes[src+1]]) <<< 12) or
+                (Int32(_dec[1+bytes[src+2]]) <<< 6) or
+                Int32(_dec[1+bytes[src+3]])
+            )
+            src += 4
+
+            output[dest]   = Byte((chunk24 >>> 16) and 0xFF)
+            output[dest+1] = Byte((chunk24 >>> 8) and 0xFF)
+            output[dest+2] = Byte(chunk24 and 0xFF)
+            dest += 3
+
+        while output[-1] == 0xFF
+            output[] = output.to(-2)
+
+        return output[]
+
+func main(input=(/dev/stdin), decode=no)
+    if decode
+        b := Base64.from_text(input.read()!)
+        say(b.decode_text()!)
+    else
+        text := input.read()!
+        say(Base64.parse(text)!.text)
-- 
cgit v1.2.3