Files
browser/src/url.zig
2025-09-30 22:13:25 -07:00

556 lines
18 KiB
Zig

const std = @import("std");
const Uri = std.Uri;
const Allocator = std.mem.Allocator;
const WebApiURL = @import("browser/url/url.zig").URL;
pub const stitch = URL.stitch;
pub const URL = struct {
uri: Uri,
raw: []const u8,
pub const empty = URL{ .uri = .{ .scheme = "" }, .raw = "" };
pub const about_blank = URL{ .uri = .{ .scheme = "" }, .raw = "about:blank" };
// We assume str will last as long as the URL
// In some cases, this is safe to do, because we know the URL is short lived.
// In most cases though, we assume the caller will just dupe the string URL
// into an arena
pub fn parse(str: []const u8, default_scheme: ?[]const u8) !URL {
var uri = Uri.parse(str) catch try Uri.parseAfterScheme(default_scheme orelse "https", str);
// special case, url scheme is about, like about:blank.
// Use an empty string as host.
if (std.mem.eql(u8, uri.scheme, "about")) {
uri.host = .{ .percent_encoded = "" };
}
if (uri.host == null) {
return error.MissingHost;
}
std.debug.assert(uri.host.? == .percent_encoded);
return .{
.uri = uri,
.raw = str,
};
}
pub fn fromURI(arena: Allocator, uri: *const Uri) !URL {
// This is embarrassing.
var buf: std.ArrayListUnmanaged(u8) = .{};
try uri.writeToStream(.{
.scheme = true,
.authentication = true,
.authority = true,
.path = true,
.query = true,
.fragment = true,
}, buf.writer(arena));
return parse(buf.items, null);
}
// Above, in `parse`, we error if a host doesn't exist
// In other words, we can't have a URL with a null host.
pub fn host(self: *const URL) []const u8 {
return self.uri.host.?.percent_encoded;
}
pub fn port(self: *const URL) ?u16 {
return self.uri.port;
}
pub fn scheme(self: *const URL) []const u8 {
return self.uri.scheme;
}
pub fn origin(self: *const URL, writer: *std.Io.Writer) !void {
return self.uri.writeToStream(writer, .{ .scheme = true, .authority = true });
}
pub fn format(self: *const URL, writer: *std.Io.Writer) !void {
return writer.writeAll(self.raw);
}
pub fn toWebApi(self: *const URL, allocator: Allocator) !WebApiURL {
return WebApiURL.init(allocator, self.uri);
}
/// Properly stitches two URL fragments together.
///
/// For URLs with a path, it will replace the last entry with the src.
/// For URLs without a path, it will add src as the path.
pub fn stitch(
allocator: Allocator,
path: []const u8,
base: []const u8,
comptime opts: StitchOpts,
) !StitchReturn(opts) {
if (base.len == 0 or isCompleteHTTPUrl(path)) {
return simpleStitch(allocator, path, opts);
}
if (path.len == 0) {
return simpleStitch(allocator, base, opts);
}
if (std.mem.startsWith(u8, path, "//")) {
// network-path reference
const index = std.mem.indexOfScalar(u8, base, ':') orelse {
return simpleStitch(allocator, path, opts);
};
const protocol = base[0..index];
if (comptime opts.null_terminated) {
return std.fmt.allocPrintSentinel(allocator, "{s}:{s}", .{ protocol, path }, 0);
}
return std.fmt.allocPrint(allocator, "{s}:{s}", .{ protocol, path });
}
// Quick hack because domains have to be at least 3 characters.
// Given https://a.b this will point to 'a'
// Given http://a.b this will point '.'
// Either way, we just care about this value to find the start of the path
const protocol_end: usize = if (isCompleteHTTPUrl(base)) 8 else 0;
var root = base;
if (std.mem.indexOfScalar(u8, base[protocol_end..], '/')) |pos| {
root = base[0 .. pos + protocol_end];
}
if (path[0] == '/') {
if (comptime opts.null_terminated) {
return std.fmt.allocPrintSentinel(allocator, "{s}{s}", .{ root, path }, 0);
}
return std.fmt.allocPrint(allocator, "{s}{s}", .{ root, path });
}
var old_path = std.mem.trimStart(u8, base[root.len..], "/");
if (std.mem.lastIndexOfScalar(u8, old_path, '/')) |pos| {
old_path = old_path[0..pos];
} else {
old_path = "";
}
// We preallocate all of the space possibly needed.
// This is the root, old_path, new path, 3 slashes and perhaps a null terminated slot.
var out = try allocator.alloc(u8, root.len + old_path.len + path.len + 3 + if (comptime opts.null_terminated) 1 else 0);
var end: usize = 0;
@memmove(out[0..root.len], root);
end += root.len;
out[root.len] = '/';
end += 1;
// If we don't have an old path, do nothing here.
if (old_path.len > 0) {
@memmove(out[end .. end + old_path.len], old_path);
end += old_path.len;
out[end] = '/';
end += 1;
}
@memmove(out[end .. end + path.len], path);
end += path.len;
var read: usize = root.len;
var write: usize = root.len;
// Strip out ./ and ../. This is done in-place, because doing so can
// only ever make `out` smaller. After this, `out` cannot be freed by
// an allocator, which is ok, because we expect allocator to be an arena.
while (read < end) {
if (std.mem.startsWith(u8, out[read..], "./")) {
read += 2;
continue;
}
if (std.mem.startsWith(u8, out[read..], "../")) {
if (write > root.len + 1) {
const search_range = out[root.len .. write - 1];
if (std.mem.lastIndexOfScalar(u8, search_range, '/')) |pos| {
write = root.len + pos + 1;
} else {
write = root.len + 1;
}
}
read += 3;
continue;
}
out[write] = out[read];
write += 1;
read += 1;
}
if (comptime opts.null_terminated) {
// we always have an extra space
out[write] = 0;
return out[0..write :0];
}
return out[0..write];
}
pub fn concatQueryString(arena: Allocator, url: []const u8, query_string: []const u8) ![]const u8 {
std.debug.assert(url.len != 0);
if (query_string.len == 0) {
return url;
}
var buf: std.ArrayListUnmanaged(u8) = .empty;
// the most space well need is the url + ('?' or '&') + the query_string
try buf.ensureTotalCapacity(arena, url.len + 1 + query_string.len);
buf.appendSliceAssumeCapacity(url);
if (std.mem.indexOfScalar(u8, url, '?')) |index| {
const last_index = url.len - 1;
if (index != last_index and url[last_index] != '&') {
buf.appendAssumeCapacity('&');
}
} else {
buf.appendAssumeCapacity('?');
}
buf.appendSliceAssumeCapacity(query_string);
return buf.items;
}
};
const StitchOpts = struct {
alloc: AllocWhen = .always,
null_terminated: bool = false,
const AllocWhen = enum {
always,
if_needed,
};
};
fn StitchReturn(comptime opts: StitchOpts) type {
return if (opts.null_terminated) [:0]const u8 else []const u8;
}
fn simpleStitch(allocator: Allocator, url: []const u8, comptime opts: StitchOpts) !StitchReturn(opts) {
if (comptime opts.null_terminated) {
return allocator.dupeZ(u8, url);
}
if (comptime opts.alloc == .always) {
return allocator.dupe(u8, url);
}
return url;
}
fn isCompleteHTTPUrl(url: []const u8) bool {
if (url.len < 8) {
return false;
}
if (!std.ascii.startsWithIgnoreCase(url, "http")) {
return false;
}
var pos: usize = 4;
if (url[4] == 's' or url[4] == 'S') {
pos = 5;
}
return std.mem.startsWith(u8, url[pos..], "://");
}
const testing = @import("testing.zig");
test "URL: isCompleteHTTPUrl" {
try testing.expectEqual(true, isCompleteHTTPUrl("http://lightpanda.io/about"));
try testing.expectEqual(true, isCompleteHTTPUrl("HttP://lightpanda.io/about"));
try testing.expectEqual(true, isCompleteHTTPUrl("httpS://lightpanda.io/about"));
try testing.expectEqual(true, isCompleteHTTPUrl("HTTPs://lightpanda.io/about"));
try testing.expectEqual(false, isCompleteHTTPUrl("/lightpanda.io"));
try testing.expectEqual(false, isCompleteHTTPUrl("../../about"));
try testing.expectEqual(false, isCompleteHTTPUrl("about"));
try testing.expectEqual(false, isCompleteHTTPUrl("//lightpanda.io"));
try testing.expectEqual(false, isCompleteHTTPUrl("//lightpanda.io/about"));
}
test "URL: stitch" {
defer testing.reset();
const Case = struct {
base: []const u8,
path: []const u8,
expected: []const u8,
};
const cases = [_]Case{
.{
.base = "https://lightpanda.io/xyz/abc/123",
.path = "something1.js",
.expected = "https://lightpanda.io/xyz/abc/something1.js",
},
.{
.base = "https://lightpanda.io/xyz/abc/123",
.path = "/something2.js",
.expected = "https://lightpanda.io/something2.js",
},
.{
.base = "https://lightpanda.io/",
.path = "something3.js",
.expected = "https://lightpanda.io/something3.js",
},
.{
.base = "https://lightpanda.io/",
.path = "/something4.js",
.expected = "https://lightpanda.io/something4.js",
},
.{
.base = "https://lightpanda.io",
.path = "something5.js",
.expected = "https://lightpanda.io/something5.js",
},
.{
.base = "https://lightpanda.io",
.path = "abc/something6.js",
.expected = "https://lightpanda.io/abc/something6.js",
},
.{
.base = "https://lightpanda.io/nested",
.path = "abc/something7.js",
.expected = "https://lightpanda.io/abc/something7.js",
},
.{
.base = "https://lightpanda.io/nested/",
.path = "abc/something8.js",
.expected = "https://lightpanda.io/nested/abc/something8.js",
},
.{
.base = "https://lightpanda.io/nested/",
.path = "/abc/something9.js",
.expected = "https://lightpanda.io/abc/something9.js",
},
.{
.base = "https://lightpanda.io/nested/",
.path = "http://www.github.com/lightpanda-io/",
.expected = "http://www.github.com/lightpanda-io/",
},
.{
.base = "https://lightpanda.io/nested/",
.path = "",
.expected = "https://lightpanda.io/nested/",
},
.{
.base = "https://lightpanda.io/abc/aaa",
.path = "./hello/./world",
.expected = "https://lightpanda.io/abc/hello/world",
},
.{
.base = "https://lightpanda.io/abc/aaa/",
.path = "../hello",
.expected = "https://lightpanda.io/abc/hello",
},
.{
.base = "https://lightpanda.io/abc/aaa",
.path = "../hello",
.expected = "https://lightpanda.io/hello",
},
.{
.base = "https://lightpanda.io/abc/aaa/",
.path = "./.././.././hello",
.expected = "https://lightpanda.io/hello",
},
.{
.base = "some/page",
.path = "hello",
.expected = "some/hello",
},
.{
.base = "some/page/",
.path = "hello",
.expected = "some/page/hello",
},
.{
.base = "some/page/other",
.path = ".././hello",
.expected = "some/hello",
},
.{
.path = "//static.lightpanda.io/hello.js",
.base = "https://lightpanda.io/about/",
.expected = "https://static.lightpanda.io/hello.js",
},
};
for (cases) |case| {
const result = try stitch(testing.arena_allocator, case.path, case.base, .{});
try testing.expectString(case.expected, result);
}
}
test "URL: stitch regression (#1093)" {
defer testing.reset();
const Case = struct {
base: []const u8,
path: []const u8,
expected: []const u8,
};
const cases = [_]Case{
.{
.base = "https://alas.aws.amazon.com/alas2.html",
.path = "../static/bootstrap.min.css",
.expected = "https://alas.aws.amazon.com/static/bootstrap.min.css",
},
};
for (cases) |case| {
const result = try stitch(testing.arena_allocator, case.path, case.base, .{});
try testing.expectString(case.expected, result);
}
}
test "URL: stitch null terminated" {
defer testing.reset();
const Case = struct {
base: []const u8,
path: []const u8,
expected: []const u8,
};
const cases = [_]Case{
.{
.base = "https://lightpanda.io/xyz/abc/123",
.path = "something1.js",
.expected = "https://lightpanda.io/xyz/abc/something1.js",
},
.{
.base = "https://lightpanda.io/xyz/abc/123",
.path = "/something2.js",
.expected = "https://lightpanda.io/something2.js",
},
.{
.base = "https://lightpanda.io/",
.path = "something3.js",
.expected = "https://lightpanda.io/something3.js",
},
.{
.base = "https://lightpanda.io/",
.path = "/something4.js",
.expected = "https://lightpanda.io/something4.js",
},
.{
.base = "https://lightpanda.io",
.path = "something5.js",
.expected = "https://lightpanda.io/something5.js",
},
.{
.base = "https://lightpanda.io",
.path = "abc/something6.js",
.expected = "https://lightpanda.io/abc/something6.js",
},
.{
.base = "https://lightpanda.io/nested",
.path = "abc/something7.js",
.expected = "https://lightpanda.io/abc/something7.js",
},
.{
.base = "https://lightpanda.io/nested/",
.path = "abc/something8.js",
.expected = "https://lightpanda.io/nested/abc/something8.js",
},
.{
.base = "https://lightpanda.io/nested/",
.path = "/abc/something9.js",
.expected = "https://lightpanda.io/abc/something9.js",
},
.{
.base = "https://lightpanda.io/nested/",
.path = "http://www.github.com/lightpanda-io/",
.expected = "http://www.github.com/lightpanda-io/",
},
.{
.base = "https://lightpanda.io/nested/",
.path = "",
.expected = "https://lightpanda.io/nested/",
},
.{
.base = "https://lightpanda.io/abc/aaa",
.path = "./hello/./world",
.expected = "https://lightpanda.io/abc/hello/world",
},
.{
.base = "https://lightpanda.io/abc/aaa/",
.path = "../hello",
.expected = "https://lightpanda.io/abc/hello",
},
.{
.base = "https://lightpanda.io/abc/aaa",
.path = "../hello",
.expected = "https://lightpanda.io/hello",
},
.{
.base = "https://lightpanda.io/abc/aaa/",
.path = "./.././.././hello",
.expected = "https://lightpanda.io/hello",
},
.{
.base = "some/page",
.path = "hello",
.expected = "some/hello",
},
.{
.base = "some/page/",
.path = "hello",
.expected = "some/page/hello",
},
.{
.base = "some/page/other",
.path = ".././hello",
.expected = "some/hello",
},
.{
.path = "//static.lightpanda.io/hello.js",
.base = "https://lightpanda.io/about/",
.expected = "https://static.lightpanda.io/hello.js",
},
};
for (cases) |case| {
const result = try stitch(testing.arena_allocator, case.path, case.base, .{ .null_terminated = true });
try testing.expectString(case.expected, result);
}
}
test "URL: concatQueryString" {
defer testing.reset();
const arena = testing.arena_allocator;
{
const url = try URL.concatQueryString(arena, "https://www.lightpanda.io/", "");
try testing.expectEqual("https://www.lightpanda.io/", url);
}
{
const url = try URL.concatQueryString(arena, "https://www.lightpanda.io/index?", "");
try testing.expectEqual("https://www.lightpanda.io/index?", url);
}
{
const url = try URL.concatQueryString(arena, "https://www.lightpanda.io/index?", "a=b");
try testing.expectEqual("https://www.lightpanda.io/index?a=b", url);
}
{
const url = try URL.concatQueryString(arena, "https://www.lightpanda.io/index?1=2", "a=b");
try testing.expectEqual("https://www.lightpanda.io/index?1=2&a=b", url);
}
{
const url = try URL.concatQueryString(arena, "https://www.lightpanda.io/index?1=2&", "a=b");
try testing.expectEqual("https://www.lightpanda.io/index?1=2&a=b", url);
}
}