echo -eを追加

echo.zig

@@ -13,12 +13,66 @@ fn help() !void {
     try stdout.print("使用法: echo\n", .{});
     try stdout.print("文章を表示\n\n", .{});
     try stdout.print("-n ニューラインを見逃す\n", .{});
+    try stdout.print("-e バックスラッシュエスケープ\n", .{});
     try stdout.print("-h ヘルプを表示\n", .{});
     try stdout.print("-v バージョンを表示\n", .{});
 
     try bw.flush();
 }
 
+fn parseEscape(text: [1024]u8) [1024]u8 {
+    var i: usize = 0;
+    var output: [1024]u8 = undefined;
+    var output_len: usize = 0;
+
+    while (i < text.len) {
+        if (text[i] == '\\') {
+            i += 1;
+            if (i < text.len) {
+                if (text[i] == 'n') {
+                    output[output_len] = '\n';
+                    output_len += 1;
+                } else if (text[i] == 't') {
+                    output[output_len] = '\t';
+                    output_len += 1;
+                } else if (text[i] == 'r') {
+                    output[output_len] = '\r';
+                    output_len += 1;
+                } else if (text[i] == 'e') {
+                    if (i + 1 < text.len and text[i + 1] == '[') {
+                        output[output_len] = '\x1B';
+                        output_len += 1;
+                        i += 1;
+                        while (i < text.len and text[i] != 'm') {
+                            output[output_len] = text[i];
+                            output_len += 1;
+                            i += 1;
+                        }
+                        if (i < text.len) {
+                            output[output_len] = text[i];
+                            output_len += 1;
+                        }
+                    }
+                } else {
+                    output[output_len] = '\\';
+                    output_len += 1;
+                    output[output_len] = text[i];
+                    output_len += 1;
+                }
+
+                output_len += 1;
+            }
+        } else {
+            output[output_len] = text[i];
+            output_len += 1;
+        }
+
+        i += 1;
+    }
+
+    return output;
+}
+
 pub fn main() !void {
     var gpa = std.heap.GeneralPurposeAllocator(.{}){};
     defer _ = gpa.deinit();
@@ -48,6 +102,7 @@ pub fn main() !void {
     }
 
     var isnonl = false;
+    var isescp = false;
     for (option.items) |i| {
         if (i == 'h') {
             try help();
@@ -60,12 +115,19 @@ pub fn main() !void {
         if (i == 'n') {
             isnonl = true;
         }
+        if (i == 'e') {
+            isescp = true;
+        }
     }
 
     const stdof = io.getStdOut().writer();
     var bw = io.bufferedWriter(stdof);
     const stdout = bw.writer();
 
+    if (isescp) {
+        text = parseEscape(text);
+    }
+
     if (isnonl) {
         try stdout.print("{s}", .{text[0..text_len]});
     } else {