╭─────────────╮ │scroll to top│ ╰─────────────╯ ╭ web.zig ──────────────────────────────────────────────────────╮ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ ╰───────────────────────────────────────────────────────────────╯
🬐 🬠 🬞🬂🬏 🬟 🬑 🬟 🬑 ╭89200f97..╮ 89200f97.. see-em: 🬋🬋🬋 🬋🬋🬋 🬋 🬋 │files │ commits refs discuss issues new login 🬐 🬠 🬐 🬠 🬑 🬟 🬰 ╰──────────╯ (623) user
╭────╮ ╭ clone ─ ─ ─ ─ ─ ─ ─ ─ ─ ─ ─ ─ ─ ─ ╮ │http│ ssh │ │ ╰────╯ ╰ ─ ─ ─ ─ ─ ─ ─ ─ ─ ─ ─ ─ ─ ─ ─ ─ ─ ╯
.. embed/ event/ test/ ui/ command.zig diff3.zig event.zig find.zig fork.zig lib.zig main.zig main_wasm.zig markdown.zig patch.zig progress.zig push.zig search.zig search_commit.zig search_thread.zig serve.zig serve_common.zig serve_http.zig serve_ssh.zig serve_ssh_protocol.zig test.zig testnet.zig try.zig ui.zig ╭─────────────────────────────────╮ │web.zig │ ╰─────────────────────────────────╯
2178 // a double-width rune is pinned inside a 2ch span so the 2179 // fallback glyph's advance width can't shift the rest of the row 2180 const wide = x + 1 < grid.size.width and (try grid.cell(x + 1, y)).continuation; 2181 if (wide) { 2182 try output.appendSlice(allocator, "<span class=\"w2\">"); 2183 try appendEscapedHtml(allocator, output, rune_text); 2184 try output.appendSlice(allocator, "</span>"); 2185 } else { 2186 try appendEscapedHtml(allocator, output, rune_text); 2187 } 2188 } else { 2189 try appendEscapedHtml(allocator, output, " "); 2190 } 2191 } 2192 if (open_link != null) try output.appendSlice(allocator, "</a>"); 2193 if (open_tag) |t| try output.appendSlice(allocator, t.closeTag()); 2194 try output.append(allocator, '\n'); 2195 } 2196 try output.appendSlice(allocator, "</div>"); 2197 2198 // native controls live in their panel, beside the replaceable cells. their 2199 // stable keys let JS update layout without recreating their DOM nodes, and 2200 // being actual descendants of a scroll gives them native movement/clipping. 2201 try renderPanelControls(allocator, output, focus, session, root_focus, &excluded); 2202 2203 // each child scroll becomes a natively-scrollable div positioned over its 2204 // viewport, holding its full content rendered recursively. 2205 for (direct.items) |id| { 2206 const child = focus.children.get(id) orelse continue; 2207 const info = child.focus.scroll orelse continue; 2208 const r = child.rect; 2209 // overflow only on the axes the widget scrolls; `auto` shows a bar only 2210 // when that axis actually overflows. the other axis is clipped (hidden), 2211 // matching how the terminal Scroll handles its non-scrolling axis. 2212 const overflow = switch (info.direction) { 2213 .vert => "overflow-x:hidden;overflow-y:auto", 2214 .horiz => "overflow-x:auto;overflow-y:hidden", 2215 .both => "overflow:auto", 2216 }; 2217 // the id carries a content version so JS preserves the native scroll 2218 // position across re-renders of the same content but resets it when the 2219 // content is replaced — e.g. selecting a different commit. the widget's 2220 // scroll offset (in cells) rides along so JS can apply it when it has no 2221 // preserved position, letting a wasm-side scrollToRect (the files list 2222 // scrolling to its selected row on page load) reach the browser. 2223 var buf: [256]u8 = undefined; 2224 try output.appendSlice(allocator, try std.fmt.bufPrint(&buf, "<div class=\"scroll\" data-key=\"scroll:{d}\" data-scroll-id=\"{d}-{d}\" data-scroll-direction=\"{s}\" data-scroll-x=\"{d}\" data-scroll-y=\"{d}\" style=\"left:{d}ch;top:{d}em;width:{d}ch;height:{d}em;{s}\">", .{ id, id, child.focus.version, @tagName(info.direction), info.offset_x, info.offset_y, r.x, r.y, r.size.width, r.size.height, overflow })); 2225 try renderPanel(allocator, output, child.focus, info.content, session, root_focus); 2226 try output.appendSlice(allocator, "</div>"); 2227 } 2228 } 2229 2230 const form_prefix = "form:"; 2231 const form_id_prefix = "haxy-form-"; 2232 2233 fn formAction(focus: *const Focus) ?[]const u8 { 2234 return switch (focus.kind) { 2235 .custom => |custom| if (std.mem.startsWith(u8, custom, form_prefix)) custom[form_prefix.len..] else null, 2236 else => null, 2237 }; 2238 } 2239 2240 // find the form ancestor of a flattened focus-tree child. html's `form` 2241 // attribute then associates the control with that form without requiring the 2242 // form and control to share a DOM parent. 2243 fn formOwner(root_focus: *Focus, focus_id: usize) ?usize { 2244 var id = focus_id; 2245 while (root_focus.children.get(id)) |child| { 2246 const parent_id = child.parent_id; 2247 if (parent_id == root_focus.id) return if (formAction(root_focus) != null) root_focus.id else null; 2248 const parent = root_focus.children.get(parent_id) orelse return null; 2249 if (formAction(parent.focus) != null) return parent_id; 2250 id = parent_id; 2251 } 2252 return null; 2253 } 2254 2255 fn appendFormAttribute(allocator: std.mem.Allocator, output: *std.ArrayList(u8), root_focus: *Focus, focus_id: usize) !void { 2256 const form_id = formOwner(root_focus, focus_id) orelse return; 2257 var buf: [64]u8 = undefined; 2258 try output.appendSlice(allocator, try std.fmt.bufPrint(&buf, " form=\"" ++ form_id_prefix ++ "{d}\"", .{form_id})); 2259 } 2260 2261 fn renderPanelControls( 2262 allocator: std.mem.Allocator, 2263 output: *std.ArrayList(u8), 2264 focus: *Focus, 2265 session: *ui.Session, 2266 root_focus: *Focus, 2267 excluded: *const std.AutoHashMapUnmanaged(usize, void), 2268 ) !void { 2269 var iter = focus.children.iterator(); 2270 while (iter.next()) |entry| { 2271 const id = entry.key_ptr.*; 2272 if (excluded.contains(id)) continue; 2273 const child = entry.value_ptr.*; 2274 const r = child.rect; 2275 2276 if (r.size.width == 0 or r.size.height == 0) continue; // not laid out, rather than merely off-screen 2277 2278 switch (child.focus.kind) { 2279 .text_input, .text_input_password, .text_area => { 2280 const ti = session.text_inputs.get(id) orelse continue; 2281 2282 const inner_left = r.x + 1; 2283 const inner_top = r.y + 1; 2284 const inner_width = if (r.size.width > 2) r.size.width - 2 else 0; 2285 const preserve = !ti.options.read_only; 2286 2287 if (child.focus.kind == .text_area) { 2288 const value = try ti.text(allocator); 2289 defer allocator.free(value); 2290 var id_buf: [128]u8 = undefined; 2291 try output.appendSlice(allocator, try std.fmt.bufPrint(&id_buf, "<textarea data-key=\"control:{d}\" data-focus-id=\"{d}\"", .{ id, id })); 2292 if (preserve) try output.appendSlice(allocator, " data-preserve-value") else try output.appendSlice(allocator, " readonly"); 2293 try appendFormAttribute(allocator, output, root_focus, id); 2294 if (ti.options.name.len > 0) { 2295 try output.appendSlice(allocator, " name=\""); 2296 try appendEscapedHtml(allocator, output, ti.options.name); 2297 try output.append(allocator, '"'); 2298 } 2299 const inner_height = if (r.size.height > 2) r.size.height - 2 else 0; 2300 var pos_buf: [128]u8 = undefined; 2301 try output.appendSlice(allocator, try std.fmt.bufPrint(&pos_buf, " style=\"left:{d}ch;top:{d}em;width:{d}ch;height:{d}em\">\n", .{ inner_left, inner_top, inner_width, inner_height })); 2302 try appendEscapedHtml(allocator, output, value); 2303 try output.appendSlice(allocator, "</textarea>"); 2304 continue; 2305 } 2306 2307 var id_buf: [160]u8 = undefined; 2308 try output.appendSlice(allocator, try std.fmt.bufPrint(&id_buf, "<input type=\"{s}\" data-key=\"control:{d}\" data-focus-id=\"{d}\"", .{ if (child.focus.kind == .text_input_password) "password" else "text", id, id })); 2309 if (preserve) try output.appendSlice(allocator, " data-preserve-value") else try output.appendSlice(allocator, " readonly"); 2310 try appendFormAttribute(allocator, output, root_focus, id); 2311 if (ti.options.name.len > 0) { 2312 try output.appendSlice(allocator, " name=\""); 2313 try appendEscapedHtml(allocator, output, ti.options.name); 2314 try output.append(allocator, '"'); 2315 } 2316 if (child.focus.kind != .text_input_password) { 2317 const value = try ti.text(allocator); 2318 defer allocator.free(value); 2319 try output.appendSlice(allocator, " value=\""); 2320 try appendEscapedHtml(allocator, output, value); 2321 try output.append(allocator, '"'); 2322 } 2323 var pos_buf: [96]u8 = undefined; 2324 try output.appendSlice(allocator, try std.fmt.bufPrint(&pos_buf, " style=\"left:{d}ch;top:{d}em;width:{d}ch;height:1em\">", .{ inner_left, inner_top, inner_width })); 2325 }, 2326 .custom => |custom| { 2327 if (std.mem.eql(u8, custom, "submit") or std.mem.startsWith(u8, custom, ui.submit_action_prefix)) { 2328 if (formOwner(root_focus, id) == null) continue; 2329 var id_buf: [128]u8 = undefined; 2330 try output.appendSlice(allocator, try std.fmt.bufPrint(&id_buf, "<button type=\"submit\" data-key=\"control:{d}\" data-focus-id=\"{d}\"", .{ id, id })); 2331 try appendFormAttribute(allocator, output, root_focus, id); 2332 if (std.mem.startsWith(u8, custom, ui.submit_action_prefix)) { 2333 try output.appendSlice(allocator, " formaction=\""); 2334 try appendEscapedHtml(allocator, output, custom[ui.submit_action_prefix.len..]); 2335 try output.append(allocator, '"'); 2336 } 2337 var pos_buf: [128]u8 = undefined; 2338 try output.appendSlice(allocator, try std.fmt.bufPrint(&pos_buf, " style=\"left:{d}ch;top:{d}em;width:{d}ch;height:{d}em\"></button>", .{ r.x, r.y, r.size.width, r.size.height })); 2339 } else if (std.mem.startsWith(u8, custom, ui.radio_prefix)) { 2340 // an invisible native radio over the option, checked when the option is its row's selection 2341 const field = custom[ui.radio_prefix.len..]; 2342 const separator = std.mem.indexOfScalar(u8, field, '=') orelse continue; 2343 const row = root_focus.children.get(child.parent_id) orelse continue; 2344 var id_buf: [128]u8 = undefined; 2345 try output.appendSlice(allocator, try std.fmt.bufPrint(&id_buf, "<input type=\"radio\" data-key=\"control:{d}\" data-focus-id=\"{d}\"", .{ id, id })); 2346 try appendFormAttribute(allocator, output, root_focus, id); 2347 try output.appendSlice(allocator, " name=\""); 2348 try appendEscapedHtml(allocator, output, field[0..separator]); 2349 try output.appendSlice(allocator, "\" value=\""); 2350 try appendEscapedHtml(allocator, output, field[separator + 1 ..]); 2351 try output.append(allocator, '"'); 2352 if (row.focus.child_id == id) try output.appendSlice(allocator, " checked"); 2353 var pos_buf: [128]u8 = undefined; 2354 try output.appendSlice(allocator, try std.fmt.bufPrint(&pos_buf, " style=\"opacity:0;left:{d}ch;top:{d}em;width:{d}ch;height:{d}em\">", .{ r.x, r.y, r.size.width, r.size.height })); 2355 } else if (std.mem.startsWith(u8, custom, ui.file_input_prefix)) { 2356 try output.appendSlice(allocator, "<input type=\"file\" data-preserve-value data-action=\""); 2357 try appendEscapedHtml(allocator, output, custom[ui.file_input_prefix.len..]); 2358 var id_buf: [128]u8 = undefined; 2359 try output.appendSlice(allocator, try std.fmt.bufPrint(&id_buf, "\" data-key=\"control:{d}\" data-focus-id=\"{d}\" style=\"opacity:0;left:{d}ch;top:{d}em;width:{d}ch;height:{d}em\">", .{ id, id, r.x, r.y, r.size.width, r.size.height })); 2360 } 2361 }, 2362 else => {}, 2363 } 2364 } 2365 } 2366 2367 // emit hidden form owners beside the rendered panels. their controls point 2368 // back here with the standard HTML `form` attribute. 2369 fn renderForms(allocator: std.mem.Allocator, output: *std.ArrayList(u8), root_focus: *Focus) !void { 2370 // the focus child map preserves insertion order, which matches the order 2371 // widgets were added in code 2372 var iter = root_focus.children.iterator(); 2373 while (iter.next()) |entry| { 2374 const child = entry.value_ptr.*; 2375 const action_url = formAction(child.focus) orelse continue; 2376 2377 try output.appendSlice(allocator, "<form hidden data-key=\"form:"); 2378 var id_buf: [96]u8 = undefined; 2379 try output.appendSlice(allocator, try std.fmt.bufPrint(&id_buf, "{d}\" id=\"" ++ form_id_prefix ++ "{d}\" action=\"", .{ entry.key_ptr.*, entry.key_ptr.* })); 2380 try appendEscapedHtml(allocator, output, action_url); 2381 try output.appendSlice(allocator, "\" method=\"post\"></form>"); 2382 } 2383 } 2384 2385 // the 16 ansi colors as the browser shows them (xterm's defaults) 2386 const ansi_palette = [16]Grid.Color.Rgb{ 2387 .{ .r = 0x00, .g = 0x00, .b = 0x00 }, .{ .r = 0xcd, .g = 0x00, .b = 0x00 }, .{ .r = 0x00, .g = 0xcd, .b = 0x00 }, .{ .r = 0xcd, .g = 0xcd, .b = 0x00 }, 2388 .{ .r = 0x00, .g = 0x00, .b = 0xee }, .{ .r = 0xcd, .g = 0x00, .b = 0xcd }, .{ .r = 0x00, .g = 0xcd, .b = 0xcd }, .{ .r = 0xe5, .g = 0xe5, .b = 0xe5 }, 2389 .{ .r = 0x7f, .g = 0x7f, .b = 0x7f }, .{ .r = 0xff, .g = 0x00, .b = 0x00 }, .{ .r = 0x00, .g = 0xff, .b = 0x00 }, .{ .r = 0xff, .g = 0xff, .b = 0x00 }, 2390 .{ .r = 0x5c, .g = 0x5c, .b = 0xff }, .{ .r = 0xff, .g = 0x00, .b = 0xff }, .{ .r = 0x00, .g = 0xff, .b = 0xff }, .{ .r = 0xff, .g = 0xff, .b = 0xff }, 2391 }; 2392 2393 // resolve any color to rgb: palette colors through the ansi table and the 2394 // xterm 256-color layout (16 ansi, a 6x6x6 cube, then 24 grays) 2395 fn colorRgb(color: Grid.Color) Grid.Color.Rgb { 2396 return switch (color) { 2397 .rgb => |c| c, 2398 .ansi => |a| ansi_palette[@intFromEnum(a)], 2399 .indexed => |n| if (n < 16) 2400 ansi_palette[n] 2401 else if (n < 232) blk: { 2402 const levels = [6]u8{ 0, 0x5f, 0x87, 0xaf, 0xd7, 0xff }; 2403 const i = n - 16; 2404 break :blk .{ .r = levels[i / 36], .g = levels[(i / 6) % 6], .b = levels[i % 6] }; 2405 } else blk: { 2406 const v: u8 = 8 + (n - 232) * 10; 2407 break :blk .{ .r = v, .g = v, .b = v }; 2408 }, 2409 }; 2410 } 2411 2412 // builds an HTML ` style="color:…;background-color:…"` attribute from a 2413 // cell's style into `buf`, omitting whichever color is unset. an inverted 2414 // cell swaps the two, falling back to the page's --fg/--bg variables for 2415 // whichever side is unset. text attributes follow the colors. returns an 2416 // empty slice when nothing is set. 2417 fn styleAttr(buf: []u8, style: Grid.Style) []const u8 { 2418 if (style.eql(.{})) return buf[0..0]; 2419 const prefix = " style=\""; 2420 @memcpy(buf[0..prefix.len], prefix); 2421 var i: usize = prefix.len; 2422 const inverted = style.inverted; 2423 i = cssColor(buf, i, "color", if (inverted) style.bg else style.fg, if (inverted) "var(--bg)" else null) orelse return buf[0..0]; 2424 i = cssColor(buf, i, "background-color", if (inverted) style.fg else style.bg, if (inverted) "var(--fg)" else null) orelse return buf[0..0]; 2425 const decoration: []const u8 = if (style.underline and style.strikethrough) 2426 "text-decoration:underline line-through;" 2427 else if (style.underline) 2428 "text-decoration:underline;" 2429 else if (style.strikethrough) 2430 "text-decoration:line-through;" 2431 else 2432 ""; 2433 const attributes = std.fmt.bufPrint(buf[i..], "{s}{s}{s}{s}", .{ 2434 if (style.bold) "font-weight:bold;" else "", 2435 if (style.italic) "font-style:italic;" else "", 2436 decoration, 2437 if (style.dim) "opacity:.6;" else "", 2438 }) catch return buf[0..0]; 2439 i += attributes.len; 2440 if (i >= buf.len) return buf[0..0]; 2441 buf[i] = '"'; 2442 return buf[0 .. i + 1]; 2443 } 2444 2445 // append `prop:value;` at buf[i..] for the color, or for the fallback when 2446 // the color is unset (nothing when both are). returns the new end, or null 2447 // when it doesn't fit. 2448 fn cssColor(buf: []u8, i: usize, prop: []const u8, color: ?Grid.Color, fallback: ?[]const u8) ?usize { 2449 const s = if (color) |c| blk: { 2450 const v = colorRgb(c); 2451 break :blk std.fmt.bufPrint(buf[i..], "{s}:#{x:0>2}{x:0>2}{x:0>2};", .{ prop, v.r, v.g, v.b }) catch return null; 2452 } else if (fallback) |f| 2453 std.fmt.bufPrint(buf[i..], "{s}:{s};", .{ prop, f }) catch return null 2454 else 2455 return i; 2456 return i + s.len; 2457 } 2458 2459 // a cell's link as an href, when it's a web or mail url 2460 fn webLink(link: ?[]const u8) ?[]const u8 { 2461 const url = link orelse return null; 2462 for ([_][]const u8{ "http://", "https://", "mailto:" }) |scheme| { 2463 if (std.ascii.startsWithIgnoreCase(url, scheme)) return url; 2464 } 2465 return null; 2466 } 2467 2468 fn sameLink(a: ?[]const u8, b: ?[]const u8) bool { 2469 if (a) |x| return if (b) |y| std.mem.eql(u8, x, y) else false; 2470 return b == null; 2471 } 2472 2473 fn appendEscapedHtml(allocator: std.mem.Allocator, out: *std.ArrayList(u8), input: []const u8) !void { 2474 for (input) |ch| { 2475 switch (ch) { 2476 '&' => try out.appendSlice(allocator, "&amp;"), 2477 '<' => try out.appendSlice(allocator, "&lt;"), 2478 '>' => try out.appendSlice(allocator, "&gt;"), 2479 '"' => try out.appendSlice(allocator, "&quot;"), 2480 '\'' => try out.appendSlice(allocator, "&#39;"), 2481 else => try out.append(allocator, ch), 2482 } 2483 } 2484 } 2485 2486 // --- helpers -------------------------------------------------------------- 2487 2488 fn getCookieValue(request: *std.http.Server.Request, name: []const u8) ?[]const u8 { 2489 var iter = request.iterateHeaders(); 2490 while (iter.next()) |header| { 2491 if (!std.ascii.eqlIgnoreCase(header.name, "cookie")) continue; 2492 var pairs = std.mem.splitScalar(u8, header.value, ';'); 2493 while (pairs.next()) |pair| { 2494 const trimmed = std.mem.trim(u8, pair, " \t"); 2495 const eq = std.mem.indexOfScalar(u8, trimmed, '=') orelse continue; 2496 if (std.mem.eql(u8, trimmed[0..eq], name)) { 2497 return trimmed[eq + 1 ..]; 2498 } 2499 } 2500 } 2501 return null; 2502 } 2503 2504 fn parseFormField(allocator: std.mem.Allocator, body: []const u8, key: []const u8) !?[]u8 { 2505 var iter = std.mem.splitScalar(u8, body, '&'); 2506 while (iter.next()) |pair| { 2507 const eq = std.mem.indexOfScalar(u8, pair, '=') orelse continue; 2508 if (std.mem.eql(u8, pair[0..eq], key)) { 2509 return try decodeFormValue(allocator, pair[eq + 1 ..]); 2510 } 2511 } 2512 return null; 2513 } 2514 2515 fn readFormBody(request: *std.http.Server.Request, allocator: std.mem.Allocator) ![]u8 { 2516 var buffer: [256]u8 = undefined; 2517 return request.readerExpectNone(&buffer).allocRemaining(allocator, .limited(65536)); 2518 } 2519 2520 fn decodeFormValue(allocator: std.mem.Allocator, encoded: []const u8) ![]u8 { 2521 var out: std.ArrayList(u8) = .empty; 2522 errdefer out.deinit(allocator); 2523 var i: usize = 0; 2524 while (i < encoded.len) : (i += 1) { 2525 switch (encoded[i]) { 2526 '+' => try out.append(allocator, ' '), 2527 '%' => { 2528 if (i + 2 >= encoded.len) return error.InvalidPercentEncoding; 2529 const hi = std.fmt.charToDigit(encoded[i + 1], 16) catch return error.InvalidPercentEncoding; 2530 const lo = std.fmt.charToDigit(encoded[i + 2], 16) catch return error.InvalidPercentEncoding; 2531 try out.append(allocator, hi * 16 + lo); 2532 i += 2; 2533 }, 2534 else => try out.append(allocator, encoded[i]), 2535 } 2536 } 2537 return try out.toOwnedSlice(allocator); 2538 } 2539 2540 // disk-backed web session store. each login mints a random, opaque token 2541 // (not the user's id) that is stored as a file named by the token hex, whose 2542 // contents are the raw user_id bytes. authenticating a request is a lookup of 2543 // the cookie's token; logout deletes the file, revoking the session. there is 2544 // deliberately no expiry — a session lives until logout. form failures use 2545 // files in the flash subdirectory that the redirected GET consumes. the 2546 // directory is cleared whenever the server starts. 2547 pub const SessionStore = struct { 2548 io: std.Io, 2549 dir: std.Io.Dir, 2550 flash_dir: std.Io.Dir, 2551 auto_login: ?[token_hex_len]u8, 2552 2553 pub const token_hex_len = evt.event_id_size * 2; 2554 2555 pub fn init(io: std.Io, data_dir: std.Io.Dir) !SessionStore { 2556 try data_dir.createDirPath(io, "sessions"); 2557 const dir = try data_dir.openDir(io, "sessions", .{}); 2558 errdefer dir.close(io); 2559 try dir.deleteTree(io, "flash"); 2560 try dir.createDirPath(io, "flash"); 2561 const flash_dir = try dir.openDir(io, "flash", .{}); 2562 errdefer flash_dir.close(io); 2563 const auto_login = blk: { 2564 const file = dir.openFile(io, auto_login_name, .{ .mode = .read_only }) catch break :blk null; 2565 defer file.close(io); 2566 var token: [token_hex_len]u8 = undefined; 2567 var storage: [token_hex_len]u8 = undefined; 2568 var reader = file.reader(io, &storage); 2569 reader.interface.readSliceAll(&token) catch break :blk null; 2570 break :blk token; 2571 }; 2572 return .{ .io = io, .dir = dir, .flash_dir = flash_dir, .auto_login = auto_login }; 2573 } 2574 2575 pub fn deinit(self: SessionStore) void { 2576 self.flash_dir.close(self.io); 2577 self.dir.close(self.io); 2578 } 2579 2580 // mint a new session for user_id, returning the token hex to set as the 2581 // cookie value. 2582 pub fn create(self: SessionStore, user_id: *const [evt.event_id_size]u8) ![token_hex_len]u8 { 2583 var token: [evt.event_id_size]u8 = undefined; 2584 self.io.random(&token); 2585 const token_hex = std.fmt.bytesToHex(token, .lower); 2586 const file = try self.dir.createFile(self.io, &token_hex, .{}); 2587 defer file.close(self.io); 2588 try file.writeStreamingAll(self.io, user_id); 2589 return token_hex; 2590 } 2591 2592 fn createFlash(self: SessionStore, allocator: std.mem.Allocator, value: ui.Session.FormFeedback) ![token_hex_len]u8 { 2593 var token: [evt.event_id_size]u8 = undefined; 2594 self.io.random(&token); 2595 const token_hex = std.fmt.bytesToHex(token, .lower); 2596 const file = try self.flash_dir.createFile(self.io, &token_hex, .{}); 2597 errdefer self.flash_dir.deleteFile(self.io, &token_hex) catch {}; 2598 defer file.close(self.io); 2599 2600 var json: std.Io.Writer.Allocating = .init(allocator); 2601 defer json.deinit(); 2602 try std.json.Stringify.value(value, .{}, &json.writer); 2603 try file.writeStreamingAll(self.io, json.written()); 2604 return token_hex; 2605 } 2606 2607 fn takeFlash(self: SessionStore, allocator: std.mem.Allocator, token_hex: []const u8) ?ui.Session.FormFeedback { 2608 if (!isToken(token_hex)) return null; 2609 const file = self.flash_dir.openFile(self.io, token_hex, .{ .mode = .read_only }) catch return null; 2610 defer self.flash_dir.deleteFile(self.io, token_hex) catch {}; 2611 defer file.close(self.io); 2612 2613 var storage: [4096]u8 = undefined; 2614 var reader = file.reader(self.io, &storage); 2615 const bytes = reader.interface.allocRemaining(allocator, .limited(512 * 1024)) catch return null; 2616 return std.json.parseFromSliceLeaky(ui.Session.FormFeedback, allocator, bytes, .{}) catch null; 2617 } 2618 2619 // resolve a cookie's token to its user_id. returns false (logged out) for a 2620 // missing, malformed, or unknown token. 2621 pub fn lookup(self: SessionStore, token_hex: []const u8, out: *[evt.event_id_size]u8) bool { 2622 if (!isToken(token_hex)) return false; 2623 const file = self.dir.openFile(self.io, token_hex, .{ .mode = .read_only }) catch return false; 2624 defer file.close(self.io); 2625 var storage: [evt.event_id_size]u8 = undefined; 2626 var file_reader = file.reader(self.io, &storage); 2627 file_reader.interface.readSliceAll(out) catch return false; 2628 return true; 2629 } 2630 2631 // revoke a session. a no-op for a missing or malformed token. 2632 pub fn remove(self: SessionStore, token_hex: []const u8) void { 2633 if (!isToken(token_hex)) return; 2634 self.dir.deleteFile(self.io, token_hex) catch {}; 2635 } 2636 2637 // leave `token_hex`'s session for visitors arriving without one. only the 2638 // `try` fixture writes one. the name can't collide with a session token. 2639 pub fn offerAutoLogin(self: SessionStore, token_hex: *const [token_hex_len]u8) !void { 2640 const file = try self.dir.createFile(self.io, auto_login_name, .{}); 2641 defer file.close(self.io); 2642 try file.writeStreamingAll(self.io, token_hex); 2643 } 2644 2645 pub fn autoLogin(self: SessionStore, out: *[token_hex_len]u8) bool { 2646 out.* = self.auto_login orelse return false; 2647 return true; 2648 } 2649 2650 const auto_login_name = "auto-login"; 2651 2652 // a token is exactly token_hex_len hex chars. validating before using the 2653 // value as a path keeps attacker-supplied cookies from escaping the 2654 // sessions dir (e.g. via "/" or ".." bytes). 2655 fn isToken(token_hex: []const u8) bool { 2656 if (token_hex.len != token_hex_len) return false; 2657 for (token_hex) |c| if (!std.ascii.isHex(c)) return false; 2658 return true; 2659 } 2660 }; 2661