const std = @import("std"); pub fn hexdump(stream: anytype, header: [] const u8, buffer: [] const u8) std.os.WriteError!void { // Print a header. 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; // First line, first left side (simple number). try stream.print("\n {d:0>4}: ", .{ hexb }); // Loop on all values in the buffer (i from 0 to buffer.len). var i: u32 = 0; while (i < buffer.len) : (i += 1) { // Print actual hexadecimal value. try stream.print("{X:0>2} ", .{ buffer[i] }); // What to print (simple ascii text, right side). if (buffer[i] >= ' ' and buffer[i] <= '~') { ascii[(i % 16)] = buffer[i]; } else { ascii[(i % 16)] = '.'; } // Next input is a multiple of 8 = extra space. if ((i + 1) % 8 == 0) { try stream.writeAll(" "); } // No next input: print the right amount of spaces. if ((i + 1) == buffer.len) { // Each line is 16 bytes to print, each byte takes 3 characters. var missing_spaces = 3 * (15 - (i%16)); // Missing an extra space if the current index % 16 is less than 7. if ((i%16) < 7) { missing_spaces += 1; } while (missing_spaces > 0) : (missing_spaces -= 1) { try stream.writeAll(" "); } } // Every 16 bytes: print ascii text and line return. // Case 1: it's been 16 bytes AND it's the last byte to print. if ((i + 1) % 16 == 0 and (i + 1) == buffer.len) { try stream.print("{s}\n", .{ ascii[0..ascii.len] }); } // Case 2: it's been 16 bytes but it's not the end of the buffer. else if ((i + 1) % 16 == 0 and (i + 1) != buffer.len) { try stream.print("{s}\n", .{ ascii[0..ascii.len] }); hexb += 16; try stream.print(" {d:0>4}: ", .{ hexb }); } // Case 3: not the end of the 16 bytes row but it's the end of the buffer. else if ((i + 1) % 16 != 0 and (i + 1) == buffer.len) { try stream.print(" {s}\n", .{ ascii[0..((i+1) % 16)] }); } // Case 4: not the end of the 16 bytes row and not the end of the buffer. // Do nothing. } try stream.writeAll("\n"); } const print = std.debug.print; test "36-byte hexdump test" { print("\nPrint hexdump, NO AUTOMATIC VERIFICATION, READ SOURCE CODE\n", .{}); var buffer = "hello this is a simple text to print"; var hexbuf: [2000]u8 = undefined; var hexfbs = std.io.fixedBufferStream(&hexbuf); var hexwriter = hexfbs.writer(); try hexdump(hexwriter, "Hello World", buffer); print("{s}\n", .{hexfbs.getWritten()}); } test "32-byte hexdump test" { print("\nPrint hexdump, NO AUTOMATIC VERIFICATION, READ SOURCE CODE\n", .{}); var buffer = "THIS IS THE END, MY ONLY... END"; var hexbuf: [2000]u8 = undefined; var hexfbs = std.io.fixedBufferStream(&hexbuf); var hexwriter = hexfbs.writer(); try hexdump(hexwriter, "Hello World", buffer); print("{s}\n", .{hexfbs.getWritten()}); } test "26-byte hexdump test" { print("\nPrint hexdump, NO AUTOMATIC VERIFICATION, READ SOURCE CODE\n", .{}); var buffer = "hello this is another text"; var hexbuf: [2000]u8 = undefined; var hexfbs = std.io.fixedBufferStream(&hexbuf); var hexwriter = hexfbs.writer(); try hexdump(hexwriter, "Hello World", buffer); print("{s}\n", .{hexfbs.getWritten()}); } test "1-byte hexdump test" { print("\nPrint hexdump, NO AUTOMATIC VERIFICATION, READ SOURCE CODE\n", .{}); var buffer = "h"; var hexbuf: [2000]u8 = undefined; var hexfbs = std.io.fixedBufferStream(&hexbuf); var hexwriter = hexfbs.writer(); try hexdump(hexwriter, "Hello World", buffer); print("{s}\n", .{hexfbs.getWritten()}); } test "0-byte hexdump test" { print("\nPrint hexdump, NO AUTOMATIC VERIFICATION, READ SOURCE CODE\n", .{}); var buffer = ""; var hexbuf: [2000]u8 = undefined; var hexfbs = std.io.fixedBufferStream(&hexbuf); var hexwriter = hexfbs.writer(); try hexdump(hexwriter, "Hello World", buffer); print("{s}\n", .{hexfbs.getWritten()}); }