╭─────────────╮ │scroll to top│ ╰─────────────╯ ╭ web.zig ──────────────────────────────────────────────────────╮ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ ╰───────────────────────────────────────────────────────────────╯
🬐 🬠 🬞🬂🬏 🬟 🬑 🬟 🬑 ╭337df9ae..╮ 337df9ae.. see-em: 🬋🬋🬋 🬋🬋🬋 🬋 🬋 │files │ commits refs discuss issues new login 🬐 🬠 🬐 🬠 🬑 🬟 🬰 ╰──────────╯ (591) 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 │ ╰─────────────────────────────────╯
2128 if (open_tag) |t| try output.appendSlice(allocator, t.closeTag()); 2129 try output.append(allocator, '\n'); 2130 } 2131 try output.appendSlice(allocator, "</div>"); 2132 2133 // native controls live in their panel, beside the replaceable cells. their 2134 // stable keys let JS update layout without recreating their DOM nodes, and 2135 // being actual descendants of a scroll gives them native movement/clipping. 2136 try renderPanelControls(allocator, output, focus, session, root_focus, &excluded); 2137 2138 // each child scroll becomes a natively-scrollable div positioned over its 2139 // viewport, holding its full content rendered recursively. 2140 for (direct.items) |id| { 2141 const child = focus.children.get(id) orelse continue; 2142 const info = child.focus.scroll orelse continue; 2143 const r = child.rect; 2144 // overflow only on the axes the widget scrolls; `auto` shows a bar only 2145 // when that axis actually overflows. the other axis is clipped (hidden), 2146 // matching how the terminal Scroll handles its non-scrolling axis. 2147 const overflow = switch (info.direction) { 2148 .vert => "overflow-x:hidden;overflow-y:auto", 2149 .horiz => "overflow-x:auto;overflow-y:hidden", 2150 .both => "overflow:auto", 2151 }; 2152 // the id carries a content version so JS preserves the native scroll 2153 // position across re-renders of the same content but resets it when the 2154 // content is replaced — e.g. selecting a different commit. the widget's 2155 // scroll offset (in cells) rides along so JS can apply it when it has no 2156 // preserved position, letting a wasm-side scrollToRect (the files list 2157 // scrolling to its selected row on page load) reach the browser. 2158 var buf: [256]u8 = undefined; 2159 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 })); 2160 try renderPanel(allocator, output, child.focus, info.content, session, root_focus); 2161 try output.appendSlice(allocator, "</div>"); 2162 } 2163 } 2164 2165 const form_prefix = "form:"; 2166 const form_id_prefix = "haxy-form-"; 2167 2168 fn formAction(focus: *const Focus) ?[]const u8 { 2169 return switch (focus.kind) { 2170 .custom => |custom| if (std.mem.startsWith(u8, custom, form_prefix)) custom[form_prefix.len..] else null, 2171 else => null, 2172 }; 2173 } 2174 2175 // find the form ancestor of a flattened focus-tree child. html's `form` 2176 // attribute then associates the control with that form without requiring the 2177 // form and control to share a DOM parent. 2178 fn formOwner(root_focus: *Focus, focus_id: usize) ?usize { 2179 var id = focus_id; 2180 while (root_focus.children.get(id)) |child| { 2181 const parent_id = child.parent_id; 2182 if (parent_id == root_focus.id) return if (formAction(root_focus) != null) root_focus.id else null; 2183 const parent = root_focus.children.get(parent_id) orelse return null; 2184 if (formAction(parent.focus) != null) return parent_id; 2185 id = parent_id; 2186 } 2187 return null; 2188 } 2189 2190 fn appendFormAttribute(allocator: std.mem.Allocator, output: *std.ArrayList(u8), root_focus: *Focus, focus_id: usize) !void { 2191 const form_id = formOwner(root_focus, focus_id) orelse return; 2192 var buf: [64]u8 = undefined; 2193 try output.appendSlice(allocator, try std.fmt.bufPrint(&buf, " form=\"" ++ form_id_prefix ++ "{d}\"", .{form_id})); 2194 } 2195 2196 fn renderPanelControls( 2197 allocator: std.mem.Allocator, 2198 output: *std.ArrayList(u8), 2199 focus: *Focus, 2200 session: *ui.Session, 2201 root_focus: *Focus, 2202 excluded: *const std.AutoHashMapUnmanaged(usize, void), 2203 ) !void { 2204 var iter = focus.children.iterator(); 2205 while (iter.next()) |entry| { 2206 const id = entry.key_ptr.*; 2207 if (excluded.contains(id)) continue; 2208 const child = entry.value_ptr.*; 2209 const r = child.rect; 2210 2211 if (r.size.width == 0 or r.size.height == 0) continue; // not laid out, rather than merely off-screen 2212 2213 switch (child.focus.kind) { 2214 .text_input, .text_input_password, .text_area => { 2215 const ti = session.text_inputs.get(id) orelse continue; 2216 2217 const inner_left = r.x + 1; 2218 const inner_top = r.y + 1; 2219 const inner_width = if (r.size.width > 2) r.size.width - 2 else 0; 2220 const preserve = !ti.options.read_only; 2221 2222 if (child.focus.kind == .text_area) { 2223 const value = try ti.text(allocator); 2224 defer allocator.free(value); 2225 var id_buf: [128]u8 = undefined; 2226 try output.appendSlice(allocator, try std.fmt.bufPrint(&id_buf, "<textarea data-key=\"control:{d}\" data-focus-id=\"{d}\"", .{ id, id })); 2227 if (preserve) try output.appendSlice(allocator, " data-preserve-value") else try output.appendSlice(allocator, " readonly"); 2228 try appendFormAttribute(allocator, output, root_focus, id); 2229 if (ti.options.name.len > 0) { 2230 try output.appendSlice(allocator, " name=\""); 2231 try appendEscapedHtml(allocator, output, ti.options.name); 2232 try output.append(allocator, '"'); 2233 } 2234 const inner_height = if (r.size.height > 2) r.size.height - 2 else 0; 2235 var pos_buf: [128]u8 = undefined; 2236 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 })); 2237 try appendEscapedHtml(allocator, output, value); 2238 try output.appendSlice(allocator, "</textarea>"); 2239 continue; 2240 } 2241 2242 var id_buf: [160]u8 = undefined; 2243 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 })); 2244 if (preserve) try output.appendSlice(allocator, " data-preserve-value") else try output.appendSlice(allocator, " readonly"); 2245 try appendFormAttribute(allocator, output, root_focus, id); 2246 if (ti.options.name.len > 0) { 2247 try output.appendSlice(allocator, " name=\""); 2248 try appendEscapedHtml(allocator, output, ti.options.name); 2249 try output.append(allocator, '"'); 2250 } 2251 if (child.focus.kind != .text_input_password) { 2252 const value = try ti.text(allocator); 2253 defer allocator.free(value); 2254 try output.appendSlice(allocator, " value=\""); 2255 try appendEscapedHtml(allocator, output, value); 2256 try output.append(allocator, '"'); 2257 } 2258 var pos_buf: [96]u8 = undefined; 2259 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 })); 2260 }, 2261 .custom => |custom| { 2262 if (std.mem.eql(u8, custom, "submit") or std.mem.startsWith(u8, custom, ui.submit_action_prefix)) { 2263 if (formOwner(root_focus, id) == null) continue; 2264 var id_buf: [128]u8 = undefined; 2265 try output.appendSlice(allocator, try std.fmt.bufPrint(&id_buf, "<button type=\"submit\" data-key=\"control:{d}\" data-focus-id=\"{d}\"", .{ id, id })); 2266 try appendFormAttribute(allocator, output, root_focus, id); 2267 if (std.mem.startsWith(u8, custom, ui.submit_action_prefix)) { 2268 try output.appendSlice(allocator, " formaction=\""); 2269 try appendEscapedHtml(allocator, output, custom[ui.submit_action_prefix.len..]); 2270 try output.append(allocator, '"'); 2271 } 2272 var pos_buf: [128]u8 = undefined; 2273 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 })); 2274 } else if (std.mem.startsWith(u8, custom, ui.file_input_prefix)) { 2275 try output.appendSlice(allocator, "<input type=\"file\" data-preserve-value data-action=\""); 2276 try appendEscapedHtml(allocator, output, custom[ui.file_input_prefix.len..]); 2277 var id_buf: [128]u8 = undefined; 2278 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 })); 2279 } 2280 }, 2281 else => {}, 2282 } 2283 } 2284 } 2285 2286 // emit hidden form owners beside the rendered panels. their controls point 2287 // back here with the standard HTML `form` attribute. 2288 fn renderForms(allocator: std.mem.Allocator, output: *std.ArrayList(u8), root_focus: *Focus) !void { 2289 // the focus child map preserves insertion order, which matches the order 2290 // widgets were added in code 2291 var iter = root_focus.children.iterator(); 2292 while (iter.next()) |entry| { 2293 const child = entry.value_ptr.*; 2294 const action_url = formAction(child.focus) orelse continue; 2295 2296 try output.appendSlice(allocator, "<form hidden data-key=\"form:"); 2297 var id_buf: [96]u8 = undefined; 2298 try output.appendSlice(allocator, try std.fmt.bufPrint(&id_buf, "{d}\" id=\"" ++ form_id_prefix ++ "{d}\" action=\"", .{ entry.key_ptr.*, entry.key_ptr.* })); 2299 try appendEscapedHtml(allocator, output, action_url); 2300 try output.appendSlice(allocator, "\" method=\"post\"></form>"); 2301 } 2302 } 2303 2304 // the 16 ansi colors as the browser shows them (xterm's defaults) 2305 const ansi_palette = [16]Grid.Color.Rgb{ 2306 .{ .r = 0x00, .g = 0x00, .b = 0x00 }, .{ .r = 0xcd, .g = 0x00, .b = 0x00 }, .{ .r = 0x00, .g = 0xcd, .b = 0x00 }, .{ .r = 0xcd, .g = 0xcd, .b = 0x00 }, 2307 .{ .r = 0x00, .g = 0x00, .b = 0xee }, .{ .r = 0xcd, .g = 0x00, .b = 0xcd }, .{ .r = 0x00, .g = 0xcd, .b = 0xcd }, .{ .r = 0xe5, .g = 0xe5, .b = 0xe5 }, 2308 .{ .r = 0x7f, .g = 0x7f, .b = 0x7f }, .{ .r = 0xff, .g = 0x00, .b = 0x00 }, .{ .r = 0x00, .g = 0xff, .b = 0x00 }, .{ .r = 0xff, .g = 0xff, .b = 0x00 }, 2309 .{ .r = 0x5c, .g = 0x5c, .b = 0xff }, .{ .r = 0xff, .g = 0x00, .b = 0xff }, .{ .r = 0x00, .g = 0xff, .b = 0xff }, .{ .r = 0xff, .g = 0xff, .b = 0xff }, 2310 }; 2311 2312 // resolve any color to rgb: palette colors through the ansi table and the 2313 // xterm 256-color layout (16 ansi, a 6x6x6 cube, then 24 grays) 2314 fn colorRgb(color: Grid.Color) Grid.Color.Rgb { 2315 return switch (color) { 2316 .rgb => |c| c, 2317 .ansi => |a| ansi_palette[@intFromEnum(a)], 2318 .indexed => |n| if (n < 16) 2319 ansi_palette[n] 2320 else if (n < 232) blk: { 2321 const levels = [6]u8{ 0, 0x5f, 0x87, 0xaf, 0xd7, 0xff }; 2322 const i = n - 16; 2323 break :blk .{ .r = levels[i / 36], .g = levels[(i / 6) % 6], .b = levels[i % 6] }; 2324 } else blk: { 2325 const v: u8 = 8 + (n - 232) * 10; 2326 break :blk .{ .r = v, .g = v, .b = v }; 2327 }, 2328 }; 2329 } 2330 2331 // builds an HTML ` style="color:…;background-color:…"` attribute from a 2332 // cell's style into `buf`, omitting whichever color is unset. an inverted 2333 // cell swaps the two, falling back to the page's --fg/--bg variables for 2334 // whichever side is unset. text attributes follow the colors. returns an 2335 // empty slice when nothing is set. 2336 fn styleAttr(buf: []u8, style: Grid.Style) []const u8 { 2337 if (style.eql(.{})) return buf[0..0]; 2338 const prefix = " style=\""; 2339 @memcpy(buf[0..prefix.len], prefix); 2340 var i: usize = prefix.len; 2341 const inverted = style.inverted; 2342 i = cssColor(buf, i, "color", if (inverted) style.bg else style.fg, if (inverted) "var(--bg)" else null) orelse return buf[0..0]; 2343 i = cssColor(buf, i, "background-color", if (inverted) style.fg else style.bg, if (inverted) "var(--fg)" else null) orelse return buf[0..0]; 2344 const decoration: []const u8 = if (style.underline and style.strikethrough) 2345 "text-decoration:underline line-through;" 2346 else if (style.underline) 2347 "text-decoration:underline;" 2348 else if (style.strikethrough) 2349 "text-decoration:line-through;" 2350 else 2351 ""; 2352 const attributes = std.fmt.bufPrint(buf[i..], "{s}{s}{s}{s}", .{ 2353 if (style.bold) "font-weight:bold;" else "", 2354 if (style.italic) "font-style:italic;" else "", 2355 decoration, 2356 if (style.dim) "opacity:.6;" else "", 2357 }) catch return buf[0..0]; 2358 i += attributes.len; 2359 if (i >= buf.len) return buf[0..0]; 2360 buf[i] = '"'; 2361 return buf[0 .. i + 1]; 2362 } 2363 2364 // append `prop:value;` at buf[i..] for the color, or for the fallback when 2365 // the color is unset (nothing when both are). returns the new end, or null 2366 // when it doesn't fit. 2367 fn cssColor(buf: []u8, i: usize, prop: []const u8, color: ?Grid.Color, fallback: ?[]const u8) ?usize { 2368 const s = if (color) |c| blk: { 2369 const v = colorRgb(c); 2370 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; 2371 } else if (fallback) |f| 2372 std.fmt.bufPrint(buf[i..], "{s}:{s};", .{ prop, f }) catch return null 2373 else 2374 return i; 2375 return i + s.len; 2376 } 2377 2378 // a cell's link as an href, when it's a web or mail url 2379 fn webLink(link: ?[]const u8) ?[]const u8 { 2380 const url = link orelse return null; 2381 for ([_][]const u8{ "http://", "https://", "mailto:" }) |scheme| { 2382 if (std.ascii.startsWithIgnoreCase(url, scheme)) return url; 2383 } 2384 return null; 2385 } 2386 2387 fn sameLink(a: ?[]const u8, b: ?[]const u8) bool { 2388 if (a) |x| return if (b) |y| std.mem.eql(u8, x, y) else false; 2389 return b == null; 2390 } 2391 2392 fn appendEscapedHtml(allocator: std.mem.Allocator, out: *std.ArrayList(u8), input: []const u8) !void { 2393 for (input) |ch| { 2394 switch (ch) { 2395 '&' => try out.appendSlice(allocator, "&amp;"), 2396 '<' => try out.appendSlice(allocator, "&lt;"), 2397 '>' => try out.appendSlice(allocator, "&gt;"), 2398 '"' => try out.appendSlice(allocator, "&quot;"), 2399 '\'' => try out.appendSlice(allocator, "&#39;"), 2400 else => try out.append(allocator, ch), 2401 } 2402 } 2403 } 2404 2405 // --- helpers -------------------------------------------------------------- 2406 2407 fn getCookieValue(request: *std.http.Server.Request, name: []const u8) ?[]const u8 { 2408 var iter = request.iterateHeaders(); 2409 while (iter.next()) |header| { 2410 if (!std.ascii.eqlIgnoreCase(header.name, "cookie")) continue; 2411 var pairs = std.mem.splitScalar(u8, header.value, ';'); 2412 while (pairs.next()) |pair| { 2413 const trimmed = std.mem.trim(u8, pair, " \t"); 2414 const eq = std.mem.indexOfScalar(u8, trimmed, '=') orelse continue; 2415 if (std.mem.eql(u8, trimmed[0..eq], name)) { 2416 return trimmed[eq + 1 ..]; 2417 } 2418 } 2419 } 2420 return null; 2421 } 2422 2423 fn parseFormField(allocator: std.mem.Allocator, body: []const u8, key: []const u8) !?[]u8 { 2424 var iter = std.mem.splitScalar(u8, body, '&'); 2425 while (iter.next()) |pair| { 2426 const eq = std.mem.indexOfScalar(u8, pair, '=') orelse continue; 2427 if (std.mem.eql(u8, pair[0..eq], key)) { 2428 return try decodeFormValue(allocator, pair[eq + 1 ..]); 2429 } 2430 } 2431 return null; 2432 } 2433 2434 fn readFormBody(request: *std.http.Server.Request, allocator: std.mem.Allocator) ![]u8 { 2435 var buffer: [256]u8 = undefined; 2436 return request.readerExpectNone(&buffer).allocRemaining(allocator, .limited(65536)); 2437 } 2438 2439 fn decodeFormValue(allocator: std.mem.Allocator, encoded: []const u8) ![]u8 { 2440 var out: std.ArrayList(u8) = .empty; 2441 errdefer out.deinit(allocator); 2442 var i: usize = 0; 2443 while (i < encoded.len) : (i += 1) { 2444 switch (encoded[i]) { 2445 '+' => try out.append(allocator, ' '), 2446 '%' => { 2447 if (i + 2 >= encoded.len) return error.InvalidPercentEncoding; 2448 const hi = std.fmt.charToDigit(encoded[i + 1], 16) catch return error.InvalidPercentEncoding; 2449 const lo = std.fmt.charToDigit(encoded[i + 2], 16) catch return error.InvalidPercentEncoding; 2450 try out.append(allocator, hi * 16 + lo); 2451 i += 2; 2452 }, 2453 else => try out.append(allocator, encoded[i]), 2454 } 2455 } 2456 return try out.toOwnedSlice(allocator); 2457 } 2458 2459 // disk-backed web session store. each login mints a random, opaque token 2460 // (not the user's id) that is stored as a file named by the token hex, whose 2461 // contents are the raw user_id bytes. authenticating a request is a lookup of 2462 // the cookie's token; logout deletes the file, revoking the session. there is 2463 // deliberately no expiry — a session lives until logout. form failures use 2464 // files in the flash subdirectory that the redirected GET consumes. the 2465 // directory is cleared whenever the server starts. 2466 pub const SessionStore = struct { 2467 io: std.Io, 2468 dir: std.Io.Dir, 2469 flash_dir: std.Io.Dir, 2470 auto_login: ?[token_hex_len]u8, 2471 2472 pub const token_hex_len = evt.event_id_size * 2; 2473 2474 pub fn init(io: std.Io, data_dir: std.Io.Dir) !SessionStore { 2475 try data_dir.createDirPath(io, "sessions"); 2476 const dir = try data_dir.openDir(io, "sessions", .{}); 2477 errdefer dir.close(io); 2478 try dir.deleteTree(io, "flash"); 2479 try dir.createDirPath(io, "flash"); 2480 const flash_dir = try dir.openDir(io, "flash", .{}); 2481 errdefer flash_dir.close(io); 2482 const auto_login = blk: { 2483 const file = dir.openFile(io, auto_login_name, .{ .mode = .read_only }) catch break :blk null; 2484 defer file.close(io); 2485 var token: [token_hex_len]u8 = undefined; 2486 var storage: [token_hex_len]u8 = undefined; 2487 var reader = file.reader(io, &storage); 2488 reader.interface.readSliceAll(&token) catch break :blk null; 2489 break :blk token; 2490 }; 2491 return .{ .io = io, .dir = dir, .flash_dir = flash_dir, .auto_login = auto_login }; 2492 } 2493 2494 pub fn deinit(self: SessionStore) void { 2495 self.flash_dir.close(self.io); 2496 self.dir.close(self.io); 2497 } 2498 2499 // mint a new session for user_id, returning the token hex to set as the 2500 // cookie value. 2501 pub fn create(self: SessionStore, user_id: *const [evt.event_id_size]u8) ![token_hex_len]u8 { 2502 var token: [evt.event_id_size]u8 = undefined; 2503 self.io.random(&token); 2504 const token_hex = std.fmt.bytesToHex(token, .lower); 2505 const file = try self.dir.createFile(self.io, &token_hex, .{}); 2506 defer file.close(self.io); 2507 try file.writeStreamingAll(self.io, user_id); 2508 return token_hex; 2509 } 2510 2511 fn createFlash(self: SessionStore, allocator: std.mem.Allocator, value: ui.Session.FormFeedback) ![token_hex_len]u8 { 2512 var token: [evt.event_id_size]u8 = undefined; 2513 self.io.random(&token); 2514 const token_hex = std.fmt.bytesToHex(token, .lower); 2515 const file = try self.flash_dir.createFile(self.io, &token_hex, .{}); 2516 errdefer self.flash_dir.deleteFile(self.io, &token_hex) catch {}; 2517 defer file.close(self.io); 2518 2519 var json: std.Io.Writer.Allocating = .init(allocator); 2520 defer json.deinit(); 2521 try std.json.Stringify.value(value, .{}, &json.writer); 2522 try file.writeStreamingAll(self.io, json.written()); 2523 return token_hex; 2524 } 2525 2526 fn takeFlash(self: SessionStore, allocator: std.mem.Allocator, token_hex: []const u8) ?ui.Session.FormFeedback { 2527 if (!isToken(token_hex)) return null; 2528 const file = self.flash_dir.openFile(self.io, token_hex, .{ .mode = .read_only }) catch return null; 2529 defer self.flash_dir.deleteFile(self.io, token_hex) catch {}; 2530 defer file.close(self.io); 2531 2532 var storage: [4096]u8 = undefined; 2533 var reader = file.reader(self.io, &storage); 2534 const bytes = reader.interface.allocRemaining(allocator, .limited(512 * 1024)) catch return null; 2535 return std.json.parseFromSliceLeaky(ui.Session.FormFeedback, allocator, bytes, .{}) catch null; 2536 } 2537 2538 // resolve a cookie's token to its user_id. returns false (logged out) for a 2539 // missing, malformed, or unknown token. 2540 pub fn lookup(self: SessionStore, token_hex: []const u8, out: *[evt.event_id_size]u8) bool { 2541 if (!isToken(token_hex)) return false; 2542 const file = self.dir.openFile(self.io, token_hex, .{ .mode = .read_only }) catch return false; 2543 defer file.close(self.io); 2544 var storage: [evt.event_id_size]u8 = undefined; 2545 var file_reader = file.reader(self.io, &storage); 2546 file_reader.interface.readSliceAll(out) catch return false; 2547 return true; 2548 } 2549 2550 // revoke a session. a no-op for a missing or malformed token. 2551 pub fn remove(self: SessionStore, token_hex: []const u8) void { 2552 if (!isToken(token_hex)) return; 2553 self.dir.deleteFile(self.io, token_hex) catch {}; 2554 } 2555 2556 // leave `token_hex`'s session for visitors arriving without one. only the 2557 // `try` fixture writes one. the name can't collide with a session token. 2558 pub fn offerAutoLogin(self: SessionStore, token_hex: *const [token_hex_len]u8) !void { 2559 const file = try self.dir.createFile(self.io, auto_login_name, .{}); 2560 defer file.close(self.io); 2561 try file.writeStreamingAll(self.io, token_hex); 2562 } 2563 2564 pub fn autoLogin(self: SessionStore, out: *[token_hex_len]u8) bool { 2565 out.* = self.auto_login orelse return false; 2566 return true; 2567 } 2568 2569 const auto_login_name = "auto-login"; 2570 2571 // a token is exactly token_hex_len hex chars. validating before using the 2572 // value as a path keeps attacker-supplied cookies from escaping the 2573 // sessions dir (e.g. via "/" or ".." bytes). 2574 fn isToken(token_hex: []const u8) bool { 2575 if (token_hex.len != token_hex_len) return false; 2576 for (token_hex) |c| if (!std.ascii.isHex(c)) return false; 2577 return true; 2578 } 2579 }; 2580