Add Base64 Encode Decode in Zig (#4578)

Author: Kaamkiya

archive/z/zig/base64-encode-decode.zig

@@ -0,0 +1,60 @@
+const std = @import("std");
+const decoder = std.base64.standard.Decoder;
+const encoder = std.base64.standard.Encoder;
+const process = std.process;
+
+const stdout = std.io.getStdOut().writer();
+
+fn die() !void {
+    try stdout.writeAll("Usage: please provide a mode and a string to encode/decode\n");
+    process.exit(1);
+}
+
+pub fn main() !void {
+    var gpa = std.heap.GeneralPurposeAllocator(.{}){};
+    defer _ = gpa.deinit();
+    const allocator = gpa.allocator();
+
+    var args = process.args();
+
+    _ = args.next();
+    const mode_opt = args.next();
+    const src_opt = args.next();
+
+    if (mode_opt == null or src_opt == null) {
+        try die();
+    }
+
+    const mode = mode_opt.?;
+    const src = src_opt.?;
+
+    if (src.len == 0) {
+        try die();
+    }
+
+    if (std.mem.eql(u8, mode, "encode")) {
+        const buffer = try allocator.alloc(u8, encoder.calcSize(src.len));
+        defer allocator.free(buffer);
+
+        _ = encoder.encode(buffer, src);
+        try stdout.writeAll(buffer);
+        _ = try stdout.write("\n");
+    } else if (std.mem.eql(u8, mode, "decode")) {
+        errdefer {
+            die() catch unreachable;
+        }
+        const buflen = try decoder.calcSizeForSlice(src);
+
+        const buffer = try allocator.alloc(u8, buflen);
+        defer allocator.free(buffer);
+
+        decoder.decode(buffer, src) catch {
+            try die();
+        };
+
+        try stdout.writeAll(buffer);
+        _ = try stdout.write("\n");
+    } else {
+        try die();
+    }
+}