hexdump library

zig-impl/src/hexdump.zig

@@ -0,0 +1,79 @@
+const std = @import("std");
+const print = std.debug.print;
+
+pub fn hexdump(stream: anytype, header: [] const u8, buffer: [] const u8) std.os.WriteError!void {
+// pub fn hexdump(_: anytype, _: [] const u8, _: [] const u8) !void {
+    try stream.writeAll("\n");
+
+    if (header.len > 0) {
+        var hdr: [64] u8 = undefined;
+        var offset: usize = (hdr.len / 2) - ((header.len / 2) - 1);
+
+        std.mem.set(u8, hdr[0..hdr.len], ' ');
+        std.mem.copy(u8, hdr[offset..hdr.len], header);
+
+        try stream.writeAll(hdr[0..hdr.len]);
+        try stream.writeAll("\n");
+    }
+
+    var hexb: u32 = 0;
+    var ascii: [16] u8 = undefined;
+    try stream.print("\n  {d:0>4}:  ", .{ hexb });
+
+    var i: u32 = 0;
+    while (i < buffer.len) : (i += 1) {
+        try stream.print("{X:0>2} ", .{ buffer[i] });
+
+        if (buffer[i] >= ' ' and buffer[i] <= '~') {
+            ascii[(i % 16)] = buffer[i];
+        } else {
+            ascii[(i % 16)] = '.';
+        }
+
+        if ((i + 1) % 8 == 0 or (i + 1) == buffer.len) {
+            try stream.writeAll(" ");
+
+            if ((i + 1) % 16 == 0) {
+                hexb += 16;
+
+                if ((i + 1) != buffer.len) {
+                    try stream.print("{s}\n  {d:0>4}:  ", .{ ascii[0..ascii.len], hexb });
+                } else {
+                    try stream.print("{s}\n", .{ ascii[0..ascii.len] });
+                }
+            } else if ((i + 1) == buffer.len) {
+                var x: u32 = (i + 1) % 16;
+
+                while (x < 16) : (x += 1) {
+                    try stream.writeAll("   ");
+                }
+
+                try stream.print("{s}\n", .{ ascii[0..(i % 16)] });
+            }
+        }
+    }
+
+    try stream.writeAll("\n");
+}
+
+// test "simple hexdump test" {
+//     var buffer: [5]u8 = undefined;
+//     buffer[0] = 1;
+//     buffer[1] = 2;
+//     buffer[2] = 4;
+//     buffer[3] = 8;
+//     buffer[4] = 16;
+// 
+//     print("\n\nLet's print the full hexdump\n\n", .{});
+//     var hexbuf: [2000]u8 = undefined;
+//     var hexfbs = std.io.fixedBufferStream(&hexbuf);
+//     var hexwriter = hexfbs.writer();
+// 
+//     // try hexdump(hexfbs.writer(), "this is the header", buffer);
+//     // try hexdump(std.io.getStdOut().writer()
+//     //            , "Hello World", &buffer);
+//     try hexdump(hexwriter, "Hello World", &buffer);
+// 
+//     print("\nPRINTING\n", .{});
+//     print("{s}\n", .{hexfbs.getWritten()});
+// }