size: 2 KiB


  

1const std = @import("std");
2const t = std.testing;
3const Io = std.Io;
4
5pub fn escapeAlloc(arena: std.mem.Allocator, text: []const u8) ![]const u8 {
6    var w = std.Io.Writer.Allocating.init(arena);
7    try escape(&w.writer, text);
8    return w.written();
9}
10
11pub fn escape(out: *std.Io.Writer, text: []const u8) !void {
12    for (text) |char| {
13        switch (char) {
14            '&' => try out.writeAll("&"),
15            '"' => try out.writeAll("""),
16            '\'' => try out.writeAll("'"),
17            '<' => try out.writeAll("&lt;"),
18            '>' => try out.writeAll("&gt;"),
19            else => try out.writeByte(char),
20        }
21    }
22}
23
24test "escape" {
25    var buf: [4096]u8 = undefined;
26    inline for (.{
27        .{
28            "<script>alert(\"jello\")</script>",
29            "&lt;script&gt;alert(&quot;jello&quot;)&lt;/script&gt;",
30        },
31        .{
32            "&\"'<>",
33            "&amp;&quot;&#39;&lt;&gt;",
34        },
35    }) |case| {
36        const input = case[0];
37        const expected = case[1];
38        var w = std.Io.Writer.fixed(&buf);
39        try escape(&w, input);
40        try t.expectEqualStrings(expected, w.buffered());
41    }
42}
43
44pub fn percentEncode(out: *std.Io.Writer, text: []const u8) !void {
45    for (text) |char| {
46        switch (char) {
47            ':' => try out.writeAll("%3A"),
48            '/' => try out.writeAll("%2F"),
49            '?' => try out.writeAll("%3F"),
50            '#' => try out.writeAll("%23"),
51            '[' => try out.writeAll("%5B"),
52            ']' => try out.writeAll("%5D"),
53            '@' => try out.writeAll("%40"),
54            '!' => try out.writeAll("%21"),
55            '$' => try out.writeAll("%24"),
56            '&' => try out.writeAll("%26"),
57            '\'' => try out.writeAll("%27"),
58            '(' => try out.writeAll("%28"),
59            ')' => try out.writeAll("%29"),
60            '*' => try out.writeAll("%2A"),
61            '+' => try out.writeAll("%2B"),
62            ',' => try out.writeAll("%2C"),
63            ';' => try out.writeAll("%3B"),
64            '=' => try out.writeAll("%3D"),
65            '%' => try out.writeAll("%25"),
66            ' ' => try out.writeAll("%20"),
67            else => try out.writeByte(char),
68        }
69    }
70}
71
72pub fn percentEncodeAlloc(arena: std.mem.Allocator, text: []const u8) ![]const u8 {
73    var w = std.Io.Writer.Allocating.init(arena);
74    try percentEncode(&w.writer, text);
75    return w.written();
76}
77
78pub fn tag(w: *Io.Writer, tag_name: []const u8, text: []const u8) !void {
79    try w.print("<{s}>", .{tag_name});
80    try escape(w, text);
81    try w.print("</{s}>\n", .{tag_name});
82}