fuzzer web UI: receive coverage information

* libfuzzer: track unique runs instead of deduplicated runs - easier for consumers to notice when to recheck the covered bits. * move common definitions to `std.Build.Fuzz.abi`. build runner sends all the information needed to fuzzer web interface client needed in order to display inline coverage information along with source code.
author: Andrew Kelley <andrew@ziglang.org> 2024-08-04 15:27:13 -0700
committer: Andrew Kelley <andrew@ziglang.org> 2024-08-07 00:48:32 -0700
commit: dec7e45f7c7e61a3778767bbc7f8e1e9a33b01fa (patch)
tree: 8039451139cd95214974c5056538aca823f526d2 /lib/fuzzer
parent: 22925636f7afc0f334f1d44257c007a1d2ccd63f (diff)
download: zig-dec7e45f7c7e61a3778767bbc7f8e1e9a33b01fa.tar.gz
zig-dec7e45f7c7e61a3778767bbc7f8e1e9a33b01fa.zip
3 files changed, 224 insertions, 93 deletions
diff --git a/lib/fuzzer/index.html b/lib/fuzzer/index.html
index dadc2f91d3..0753bcae67 100644
--- a/lib/fuzzer/index.html
+++ b/lib/fuzzer/index.html
@@ -124,6 +124,7 @@
     </style>
   </head>
   <body>
+    <p id="status">Loading JavaScript...</p>
     <div id="sectSource" class="hidden">
       <h2>Source Code</h2>
       <pre><code id="sourceText"></code></pre>
diff --git a/lib/fuzzer/main.js b/lib/fuzzer/main.js
index 872ac3d4b5..6fed056a5e 100644
--- a/lib/fuzzer/main.js
+++ b/lib/fuzzer/main.js
@@ -1,95 +1,148 @@
 (function() {
-    const domSectSource = document.getElementById("sectSource");
-    const domSourceText = document.getElementById("sourceText");
-
-    let wasm_promise = fetch("main.wasm");
-    let sources_promise = fetch("sources.tar").then(function(response) {
-      if (!response.ok) throw new Error("unable to download sources");
-      return response.arrayBuffer();
-    });
-    var wasm_exports = null;
-
-    const text_decoder = new TextDecoder();
-    const text_encoder = new TextEncoder();
-
-    const eventSource = new EventSource("events");
-    eventSource.addEventListener('message', onMessage, false);
-
-    WebAssembly.instantiateStreaming(wasm_promise, {
-      js: {
-        log: function(ptr, len) {
+  const domStatus = document.getElementById("status");
+  const domSectSource = document.getElementById("sectSource");
+  const domSourceText = document.getElementById("sourceText");
+
+  let wasm_promise = fetch("main.wasm");
+  let sources_promise = fetch("sources.tar").then(function(response) {
+    if (!response.ok) throw new Error("unable to download sources");
+    return response.arrayBuffer();
+  });
+  var wasm_exports = null;
+
+  const text_decoder = new TextDecoder();
+  const text_encoder = new TextEncoder();
+
+  domStatus.textContent = "Loading WebAssembly...";
+  WebAssembly.instantiateStreaming(wasm_promise, {
+    js: {
+      log: function(ptr, len) {
+        const msg = decodeString(ptr, len);
+        console.log(msg);
+      },
+      panic: function (ptr, len) {
           const msg = decodeString(ptr, len);
-          console.log(msg);
-        },
-        panic: function (ptr, len) {
-            const msg = decodeString(ptr, len);
-            throw new Error("panic: " + msg);
-        },
+          throw new Error("panic: " + msg);
       },
-    }).then(function(obj) {
-      wasm_exports = obj.instance.exports;
-      window.wasm = obj; // for debugging
-
-      sources_promise.then(function(buffer) {
-        const js_array = new Uint8Array(buffer);
-        const ptr = wasm_exports.alloc(js_array.length);
-        const wasm_array = new Uint8Array(wasm_exports.memory.buffer, ptr, js_array.length);
-        wasm_array.set(js_array);
-        wasm_exports.unpack(ptr, js_array.length);
-
-        render();
-      });
+      emitSourceIndexChange: onSourceIndexChange,
+      emitCoverageUpdate: onCoverageUpdate,
+    },
+  }).then(function(obj) {
+    wasm_exports = obj.instance.exports;
+    window.wasm = obj; // for debugging
+    domStatus.textContent = "Loading sources tarball...";
+
+    sources_promise.then(function(buffer) {
+      domStatus.textContent = "Parsing sources...";
+      const js_array = new Uint8Array(buffer);
+      const ptr = wasm_exports.alloc(js_array.length);
+      const wasm_array = new Uint8Array(wasm_exports.memory.buffer, ptr, js_array.length);
+      wasm_array.set(js_array);
+      wasm_exports.unpack(ptr, js_array.length);
+
+      domStatus.textContent = "Waiting for server to send source location metadata...";
+      connectWebSocket();
     });
-
-    function onMessage(e) {
-      console.log("Message", e.data);
-    }
-
-    function render() {
-      domSectSource.classList.add("hidden");
-
-      // TODO this is temporary debugging data
-      renderSource("/home/andy/dev/zig/lib/std/zig/tokenizer.zig");
-    }
-
-    function renderSource(path) {
-      const decl_index = findFileRoot(path);
-      if (decl_index == null) throw new Error("file not found: " + path);
-
-      const h2 = domSectSource.children[0];
-      h2.innerText = path;
-      domSourceText.innerHTML = declSourceHtml(decl_index);
-
-      domSectSource.classList.remove("hidden");
-    }
-
-    function findFileRoot(path) {
-      setInputString(path);
-      const result = wasm_exports.find_file_root();
-      if (result === -1) return null;
-      return result;
-    }
-
-    function decodeString(ptr, len) {
-      if (len === 0) return "";
-      return text_decoder.decode(new Uint8Array(wasm_exports.memory.buffer, ptr, len));
-    }
-
-    function setInputString(s) {
-      const jsArray = text_encoder.encode(s);
-      const len = jsArray.length;
-      const ptr = wasm_exports.set_input_string(len);
-      const wasmArray = new Uint8Array(wasm_exports.memory.buffer, ptr, len);
-      wasmArray.set(jsArray);
-    }
-
-    function declSourceHtml(decl_index) {
-      return unwrapString(wasm_exports.decl_source_html(decl_index));
-    }
-
-    function unwrapString(bigint) {
-      const ptr = Number(bigint & 0xffffffffn);
-      const len = Number(bigint >> 32n);
-      return decodeString(ptr, len);
-    }
+  });
+
+  function connectWebSocket() {
+    const host = window.document.location.host;
+    const pathname = window.document.location.pathname;
+    const isHttps = window.document.location.protocol === 'https:';
+    const match = host.match(/^(.+):(\d+)$/);
+    const defaultPort = isHttps ? 443 : 80;
+    const port = match ? parseInt(match[2], 10) : defaultPort;
+    const hostName = match ? match[1] : host;
+    const wsProto = isHttps ? "wss:" : "ws:";
+    const wsUrl = wsProto + '//' + hostName + ':' + port + pathname;
+    ws = new WebSocket(wsUrl);
+    ws.binaryType = "arraybuffer";
+    ws.addEventListener('message', onWebSocketMessage, false);
+    ws.addEventListener('error', timeoutThenCreateNew, false);
+    ws.addEventListener('close', timeoutThenCreateNew, false);
+    ws.addEventListener('open', onWebSocketOpen, false);
+  }
+
+  function onWebSocketOpen() {
+    console.log("web socket opened");
+  }
+
+  function onWebSocketMessage(ev) {
+    wasmOnMessage(ev.data);
+  }
+
+  function timeoutThenCreateNew() {
+    ws.removeEventListener('message', onWebSocketMessage, false);
+    ws.removeEventListener('error', timeoutThenCreateNew, false);
+    ws.removeEventListener('close', timeoutThenCreateNew, false);
+    ws.removeEventListener('open', onWebSocketOpen, false);
+    ws = null;
+    setTimeout(connectWebSocket, 1000);
+  }
+
+  function wasmOnMessage(data) {
+    const jsArray = new Uint8Array(data);
+    const ptr = wasm_exports.message_begin(jsArray.length);
+    const wasmArray = new Uint8Array(wasm_exports.memory.buffer, ptr, jsArray.length);
+    wasmArray.set(jsArray);
+    wasm_exports.message_end();
+  }
+
+  function onSourceIndexChange() {
+    console.log("source location index metadata updated");
+    render();
+  }
+
+  function onCoverageUpdate() {
+    console.log("coverage update");
+  }
+
+  function render() {
+    domStatus.classList.add("hidden");
+    domSectSource.classList.add("hidden");
+
+    // TODO this is temporary debugging data
+    renderSource("/home/andy/dev/zig/lib/std/zig/tokenizer.zig");
+  }
+
+  function renderSource(path) {
+    const decl_index = findFileRoot(path);
+    if (decl_index == null) throw new Error("file not found: " + path);
+
+    const h2 = domSectSource.children[0];
+    h2.innerText = path;
+    domSourceText.innerHTML = declSourceHtml(decl_index);
+
+    domSectSource.classList.remove("hidden");
+  }
+
+  function findFileRoot(path) {
+    setInputString(path);
+    const result = wasm_exports.find_file_root();
+    if (result === -1) return null;
+    return result;
+  }
+
+  function decodeString(ptr, len) {
+    if (len === 0) return "";
+    return text_decoder.decode(new Uint8Array(wasm_exports.memory.buffer, ptr, len));
+  }
+
+  function setInputString(s) {
+    const jsArray = text_encoder.encode(s);
+    const len = jsArray.length;
+    const ptr = wasm_exports.set_input_string(len);
+    const wasmArray = new Uint8Array(wasm_exports.memory.buffer, ptr, len);
+    wasmArray.set(jsArray);
+  }
+
+  function declSourceHtml(decl_index) {
+    return unwrapString(wasm_exports.decl_source_html(decl_index));
+  }
+
+  function unwrapString(bigint) {
+    const ptr = Number(bigint & 0xffffffffn);
+    const len = Number(bigint >> 32n);
+    return decodeString(ptr, len);
+  }
 })();
diff --git a/lib/fuzzer/wasm/main.zig b/lib/fuzzer/wasm/main.zig
index 5045f784cc..fd785d5723 100644
--- a/lib/fuzzer/wasm/main.zig
+++ b/lib/fuzzer/wasm/main.zig
@@ -1,16 +1,19 @@
 const std = @import("std");
 const assert = std.debug.assert;
+const abi = std.Build.Fuzz.abi;
+const gpa = std.heap.wasm_allocator;
+const log = std.log;
+const Coverage = std.debug.Coverage;
 
 const Walk = @import("Walk");
 const Decl = Walk.Decl;
 const html_render = @import("html_render");
 
-const gpa = std.heap.wasm_allocator;
-const log = std.log;
-
 const js = struct {
     extern "js" fn log(ptr: [*]const u8, len: usize) void;
     extern "js" fn panic(ptr: [*]const u8, len: usize) noreturn;
+    extern "js" fn emitSourceIndexChange() void;
+    extern "js" fn emitCoverageUpdate() void;
 };
 
 pub const std_options: std.Options = .{
@@ -45,6 +48,26 @@ export fn alloc(n: usize) [*]u8 {
     return slice.ptr;
 }
 
+var message_buffer: std.ArrayListAlignedUnmanaged(u8, @alignOf(u64)) = .{};
+
+/// Resizes the message buffer to be the correct length; returns the pointer to
+/// the query string.
+export fn message_begin(len: usize) [*]u8 {
+    message_buffer.resize(gpa, len) catch @panic("OOM");
+    return message_buffer.items.ptr;
+}
+
+export fn message_end() void {
+    const msg_bytes = message_buffer.items;
+
+    const tag: abi.ToClientTag = @enumFromInt(msg_bytes[0]);
+    switch (tag) {
+        .source_index => return sourceIndexMessage(msg_bytes) catch @panic("OOM"),
+        .coverage_update => return coverageUpdateMessage(msg_bytes) catch @panic("OOM"),
+        _ => unreachable,
+    }
+}
+
 export fn unpack(tar_ptr: [*]u8, tar_len: usize) void {
     const tar_bytes = tar_ptr[0..tar_len];
     log.debug("received {d} bytes of tar file", .{tar_bytes.len});
@@ -141,3 +164,57 @@ fn fatal(comptime format: []const u8, args: anytype) noreturn {
     };
     js.panic(line.ptr, line.len);
 }
+
+fn sourceIndexMessage(msg_bytes: []u8) error{OutOfMemory}!void {
+    const Header = abi.SourceIndexHeader;
+    const header: Header = @bitCast(msg_bytes[0..@sizeOf(Header)].*);
+
+    const directories_start = @sizeOf(Header);
+    const directories_end = directories_start + header.directories_len * @sizeOf(Coverage.String);
+    const files_start = directories_end;
+    const files_end = files_start + header.files_len * @sizeOf(Coverage.File);
+    const source_locations_start = files_end;
+    const source_locations_end = source_locations_start + header.source_locations_len * @sizeOf(Coverage.SourceLocation);
+    const string_bytes = msg_bytes[source_locations_end..][0..header.string_bytes_len];
+
+    const directories: []const Coverage.String = @alignCast(std.mem.bytesAsSlice(Coverage.String, msg_bytes[directories_start..directories_end]));
+    const files: []const Coverage.File = @alignCast(std.mem.bytesAsSlice(Coverage.File, msg_bytes[files_start..files_end]));
+    const source_locations: []const Coverage.SourceLocation = @alignCast(std.mem.bytesAsSlice(Coverage.SourceLocation, msg_bytes[source_locations_start..source_locations_end]));
+
+    try updateCoverage(directories, files, source_locations, string_bytes);
+    js.emitSourceIndexChange();
+}
+
+fn coverageUpdateMessage(msg_bytes: []u8) error{OutOfMemory}!void {
+    recent_coverage_update.clearRetainingCapacity();
+    recent_coverage_update.appendSlice(gpa, msg_bytes) catch @panic("OOM");
+    js.emitCoverageUpdate();
+}
+
+var coverage = Coverage.init;
+var coverage_source_locations: std.ArrayListUnmanaged(Coverage.SourceLocation) = .{};
+/// Contains the most recent coverage update message, unmodified.
+var recent_coverage_update: std.ArrayListUnmanaged(u8) = .{};
+
+fn updateCoverage(
+    directories: []const Coverage.String,
+    files: []const Coverage.File,
+    source_locations: []const Coverage.SourceLocation,
+    string_bytes: []const u8,
+) !void {
+    coverage.directories.clearRetainingCapacity();
+    coverage.files.clearRetainingCapacity();
+    coverage.string_bytes.clearRetainingCapacity();
+    coverage_source_locations.clearRetainingCapacity();
+
+    try coverage_source_locations.appendSlice(gpa, source_locations);
+    try coverage.string_bytes.appendSlice(gpa, string_bytes);
+
+    try coverage.files.entries.resize(gpa, files.len);
+    @memcpy(coverage.files.entries.items(.key), files);
+    try coverage.files.reIndexContext(gpa, .{ .string_bytes = coverage.string_bytes.items });
+
+    try coverage.directories.entries.resize(gpa, directories.len);
+    @memcpy(coverage.directories.entries.items(.key), directories);
+    try coverage.directories.reIndexContext(gpa, .{ .string_bytes = coverage.string_bytes.items });
+}
author	Andrew Kelley <andrew@ziglang.org>	2024-08-04 15:27:13 -0700
committer	Andrew Kelley <andrew@ziglang.org>	2024-08-07 00:48:32 -0700
commit	dec7e45f7c7e61a3778767bbc7f8e1e9a33b01fa (patch)
tree	8039451139cd95214974c5056538aca823f526d2 /lib/fuzzer
parent	22925636f7afc0f334f1d44257c007a1d2ccd63f (diff)
download	zig-dec7e45f7c7e61a3778767bbc7f8e1e9a33b01fa.tar.gz zig-dec7e45f7c7e61a3778767bbc7f8e1e9a33b01fa.zip