Clear the open minors: lost marking and overrun logging, form teardown guard, line breaks and ERANGE in config, probe strength

The E-1608 source marks every restart as lost and logs each overrun; its form stops touching
siblings after the chooser destroys them; the link skips command id 0, retries a full-buffer
discover send and ignores a zero-length scan read. Session files escape \n and \r; get_int and
get_double reject out-of-range values; the UDPS port spin reports changes; a skipped source panel
says why on stderr. The E-1608 probe now checks the signal names and the reconnect itself.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

docs/claude/probe-readings.md

@@ -1890,7 +1890,8 @@ the one `[e1608] handshake with ...: Connection refused` line, `stream: ... sign
   did not run.
 - `stream: signals=4 expect=4 rate=1000.000 ok=1`: the enabled channels plus the plotted digital lines plus the
   counter, at the scan rate. `signals` below `expect` is a signal the source did not declare; `rate` off by a
-  factor is the pacer computed from the wrong aggregate.
+  factor is the pacer computed from the wrong aggregate. `ok` also requires `names=` to be the enabled analog
+  inputs, then the plotted digital lines, then `Counter`, in that order: swapped channels read `ok=0`.
 - `calibration: ai0_mean=0.50xx ok=1`: the mock's AI0 is 0.5 V under a 5 Hz sine of 0.1 V, read through
   non-trivial factory coefficients; the mean over two periods lands on 0.5 V only when `decode()` applies them.
   About `0.2043` is the **uncalibrated** reading (the calibration read failed, or `calibrate=0`); `nan` is a
@@ -1902,7 +1903,9 @@ the one `[e1608] handshake with ...: Connection refused` line, `stream: ... sign
   clamp at both ends). It needs no board; `ok=0` is a change to the calibration arithmetic.
 - `reconnect: connects=2 connected=1`, `resumed: ok=1`: the mock dropped both links at about 3 s; the source
   reported it, retried after 2 s and the frame count moved on. `connects=1` is a source that never noticed the
-  drop (neither the scan read nor the status check raised it), `resumed: ok=0` is a reconnect that did not restart the scan.
+  drop (neither the scan read nor the status check raised it), `resumed: ok=0` is a reconnect that did not restart
+  the scan (it also reads 0 when `connects` is still 1, since a frame count that grows on a link that never dropped
+  proves nothing).
 
 ## `[prefs-probe]`
 

src/layout_store.cpp

@@ -55,12 +55,23 @@ namespace {
 std::string toml_escape(const std::string& s) {
   std::string out = "\"";
   for (char c : s) {
+    // The file is read line by line, so a raw newline in a value would end the line early.
+    if (c == '\n') {
+      out += "\\n";
+    } else if (c == '\r') {
+      out += "\\r";
+    } else {
       if (c == '"' || c == '\\') out.push_back('\\');
       out.push_back(c);
     }
+  }
   return out + "\"";
 }
 
+/// The character an escape `\x` stands for: `\n` and `\r` are the two line breaks, anything else
+/// (the quote, the backslash) stands for itself.
+char unescaped(char c) { return c == 'n' ? '\n' : c == 'r' ? '\r' : c; }
+
 bool unescape(std::string& s) {
   std::string out;
   for (std::size_t i = 0; i < s.size(); ++i) {
@@ -69,8 +80,8 @@ bool unescape(std::string& s) {
       continue;
     }
     if (++i >= s.size()) return false;
-    if (s[i] == '"' || s[i] == '\\') {
-      out.push_back(s[i]);
+    if (s[i] == '"' || s[i] == '\\' || s[i] == 'n' || s[i] == 'r') {
+      out.push_back(unescaped(s[i]));
     } else {
       return false;
     }
@@ -472,9 +483,12 @@ bool load_layout(const std::string& path, LayoutState& out) {
         std::string s = v.substr(1, v.size() - 2);
         std::string out;
         for (std::size_t i = 0; i < s.size(); ++i) {
-          if (s[i] == '\\' && i + 1 < s.size()) ++i;
+          if (s[i] == '\\' && i + 1 < s.size()) {
+            out.push_back(unescaped(s[++i]));
+          } else {
             out.push_back(s[i]);
           }
+        }
         return out;
       }
       return v;

src/source/e1608/e1608_kind.cpp

@@ -81,6 +81,7 @@ struct Form {
   GtkWidget *dir[8], *do_init, *plot_counter, *ao_init[2];
   ChangeCb changed = std::make_shared<std::function<void()>>();
   bool updating = false;
+  bool alive = true;  ///< cleared when the chooser destroys the rows; handlers then touch nothing
 
   bool diff() const { return sel_of(mode) == 1; }
   int enabled_ai() const {
@@ -170,17 +171,27 @@ using FormPtr = std::shared_ptr<Form>;
 
 void on_notify(GObject*, GParamSpec*, gpointer user) {
   Form& f = **static_cast<FormPtr*>(user);
+  if (!f.alive) return;
   f.refresh();
   if (!f.updating && f.changed && *f.changed) (*f.changed)();
 }
 
 void on_edited(GtkEditable*, gpointer user) {
   Form& f = **static_cast<FormPtr*>(user);
+  if (!f.alive) return;
   if (!f.updating && f.changed && *f.changed) (*f.changed)();
 }
 
 void free_form(gpointer d, GClosure*) { delete static_cast<FormPtr*>(d); }
 
+/// "destroy" on a row group: the siblings the handlers reach by raw pointer may already be gone.
+void on_form_destroy(GtkWidget*, gpointer user) { (**static_cast<FormPtr*>(user)).alive = false; }
+
+void hook_destroy(GtkWidget* w, const FormPtr& f) {
+  g_signal_connect_data(w, "destroy", G_CALLBACK(on_form_destroy), new FormPtr(f), free_form,
+                        static_cast<GConnectFlags>(0));
+}
+
 void hook_notify(GtkWidget* w, const char* signal, const FormPtr& f) {
   g_signal_connect_data(w, signal, G_CALLBACK(on_notify), new FormPtr(f), free_form,
                         static_cast<GConnectFlags>(0));
@@ -254,6 +265,7 @@ class E1608Kind final : public SourceKind {
     f->ai_group = ai;
     adw_expander_row_set_expanded(ADW_EXPANDER_ROW(conn), TRUE);
 
+    for (GtkWidget* w : {conn, acq, ai, dio}) hook_destroy(w, f);
     for (GtkWidget* w : {f->address, f->mac, f->subnet}) hook_entry(w, f);
     for (GtkWidget* w : {f->port, f->code, f->timeout, f->rate, f->poll_rate, f->do_init,
                          f->ao_init[0], f->ao_init[1]})

src/source/e1608/e1608_link.cpp

@@ -199,9 +199,16 @@ std::vector<DeviceInfo> discover(const std::vector<std::string>& targets, int po
     } catch (const LinkError&) {
       continue;
     }
-    // A sweep may hit unreachable hosts; those sends fail and are simply skipped.
-    (void)::sendto(u.get(), &probe, 1, MSG_NOSIGNAL, reinterpret_cast<const sockaddr*>(&a),
+    // A sweep may hit unreachable hosts; those sends fail and are simply skipped. A full send
+    // buffer is not that: wait for room once and retry, so a large sweep does not lose probes.
+    const auto send_probe = [&] {
+      return ::sendto(u.get(), &probe, 1, MSG_NOSIGNAL, reinterpret_cast<const sockaddr*>(&a),
                       sizeof a);
+    };
+    if (send_probe() < 0 && (errno == EAGAIN || errno == ENOBUFS)) {
+      wait_fd(u.get(), POLLOUT, 20);
+      (void)send_probe();
+    }
   }
   const auto deadline = Clock::now() + std::chrono::milliseconds(wait_ms);
   for (;;) {
@@ -288,7 +295,8 @@ std::vector<std::uint8_t> Link::command(std::uint8_t cmd, const std::vector<std:
     while (::recv(cmd_.get(), junk, sizeof junk, MSG_DONTWAIT) > 0) {
     }
   }
-  const std::uint8_t id = ++next_id_;
+  if (++next_id_ == 0) next_id_ = 1;  // id 0 is never used, in case a board treats it specially
+  const std::uint8_t id = next_id_;
   std::vector<std::uint8_t> f;
   f.reserve(7 + payload.size());
   f.push_back(0xDB);
@@ -349,6 +357,7 @@ void Link::send_filler() {
 
 std::size_t Link::read_scan(std::uint8_t* buf, std::size_t cap, int timeout_ms) {
   if (!scan_.valid()) throw LinkError(Kind::Io, "the scan socket is not open");
+  if (cap == 0) return 0;  // recv would return 0 and read as a close
   if (!wait_fd(scan_.get(), POLLIN, timeout_ms)) return 0;
   const ssize_t n = ::recv(scan_.get(), buf, cap, MSG_DONTWAIT);
   if (n > 0) return static_cast<std::size_t>(n);

src/source/e1608/e1608_source.cpp

@@ -430,10 +430,12 @@ void E1608Source::check_status() {
     sink_->on_event(SourceEvent::Error, "scan overrun; restarting");
     restart_scan();
     pending_lost_ = 1;
+    last_logged_.clear();  // a later overrun on this connection is news again, not a retry echo
   } else if (!(st & 2) && cfg_.auto_restart && cfg_.trigger == Trigger::None) {
     // With a hardware trigger the board may report "not running" while it waits for the edge;
     // restarting then would reset the wait forever, so only the overrun bit restarts the scan.
     restart_scan();
+    pending_lost_ = 1;  // the samples between the stop and the restart are gone either way
   }
 }
 

src/source/source_config.cpp

@@ -5,6 +5,8 @@
 
 #include <algorithm>
 #include <cctype>
+#include <cerrno>
+#include <cmath>
 #include <cstdlib>
 
 namespace udpscope {
@@ -35,16 +37,18 @@ long SourceConfig::get_int(const std::string& key, long def) const {
   if (!has(key)) return def;
   const std::string v = get(key);
   char* end = nullptr;
+  errno = 0;
   const long n = std::strtol(v.c_str(), &end, 10);
-  return (end == v.c_str() || *end != '\0') ? def : n;
+  return (end == v.c_str() || *end != '\0' || errno == ERANGE) ? def : n;
 }
 
 double SourceConfig::get_double(const std::string& key, double def) const {
   if (!has(key)) return def;
   const std::string v = get(key);
   char* end = nullptr;
+  errno = 0;
   const double d = std::strtod(v.c_str(), &end);
-  return (end == v.c_str() || *end != '\0') ? def : d;
+  return (end == v.c_str() || *end != '\0' || std::isinf(d)) ? def : d;
 }
 
 bool SourceConfig::get_bool(const std::string& key, bool def) const {

src/source/udps_kind.cpp

@@ -25,6 +25,17 @@ void on_edited(GtkEditable*, gpointer user) {
   if (cb && *cb) (*cb)();
 }
 
+void on_value(GObject*, GParamSpec*, gpointer user) {
+  const auto& cb = *static_cast<ChangeCb*>(user);
+  if (cb && *cb) (*cb)();
+}
+
+void hook_value(GtkWidget* spin, const ChangeCb& cb) {
+  g_signal_connect_data(spin, "notify::value", G_CALLBACK(on_value), new ChangeCb(cb),
+                        +[](gpointer d, GClosure*) { delete static_cast<ChangeCb*>(d); },
+                        static_cast<GConnectFlags>(0));
+}
+
 void hook(GtkWidget* entry, const ChangeCb& cb) {
   g_signal_connect_data(entry, "changed", G_CALLBACK(on_edited), new ChangeCb(cb),
                         +[](gpointer d, GClosure*) { delete static_cast<ChangeCb*>(d); },
@@ -58,6 +69,7 @@ class UdpsKind final : public SourceKind {
 
     ChangeCb cb = std::make_shared<std::function<void()>>();
     hook(server, cb);
+    hook_value(port, cb);
     hook(group, cb);
     hook(iface, cb);
 

src/ui_probe.cpp

@@ -2058,8 +2058,19 @@ gboolean e1608_probe_report(gpointer user) {
   for (const SignalInfo& si : sigs) names += (names.empty() ? "" : ",") + si.name;
   const double rate = sigs.empty() ? 0.0 : sigs.front().sampling_rate;
   const std::uint64_t frames = a->model->stats().frames.load(std::memory_order_relaxed);
-  const bool stream_ok = up && sigs.size() == expect && std::fabs(rate - s.scan_rate) < 1e-6 &&
-                         frames > 0;
+  // The signals' order is part of the contract: the enabled analog inputs, then the plotted DI
+  // lines, then the counter. Swapped channels must not read ok.
+  std::string expect_names;
+  const auto add_name = [&](const std::string& n) { expect_names += (expect_names.empty() ? "" : ",") + n; };
+  for (int i = 0; i < 8; ++i) {
+    if (s.ai_on[i]) add_name("AI" + std::to_string(i));
+  }
+  for (int i = 0; i < 8; ++i) {
+    if (s.plot[i]) add_name("DI" + std::to_string(i));
+  }
+  if (s.plot_counter) add_name("Counter");
+  const bool stream_ok = up && sigs.size() == expect && names == expect_names &&
+                         std::fabs(rate - s.scan_rate) < 1e-6 && frames > 0;
   std::fprintf(stderr,
                "[e1608] stream: connected=%d signals=%zu expect=%zu names=%s frames=%" G_GUINT64_FORMAT
                " rate=%.3f ok=%d\n",
@@ -2146,13 +2157,17 @@ gboolean e1608_probe_resumed(gpointer user) {
   App* a = static_cast<App*>(user);
   if (a->window == nullptr) return G_SOURCE_REMOVE;
   const std::uint64_t after = a->model->stats().frames.load(std::memory_order_relaxed);
+  // Frames alone also grow on a link that never dropped: the reconnect must have happened too.
+  e1608::E1608Source* src = e1608_source(a);
+  const bool reconnected = src != nullptr && src->connects() >= 2;
   std::fprintf(stderr, "[e1608] resumed: frames_before=%" G_GUINT64_FORMAT " frames_after=%" G_GUINT64_FORMAT
                        " ok=%d\n",
-               g_e1608_frames_before, after, after > g_e1608_frames_before ? 1 : 0);
+               g_e1608_frames_before, after, reconnected && after > g_e1608_frames_before ? 1 : 0);
   std::fflush(stderr);
   return G_SOURCE_REMOVE;
 }
 
+/// After the mock dropped the link: the source's connect count, then (500 ms later) whether the stream moves.
 gboolean e1608_probe_reconnect(gpointer user) {
   App* a = static_cast<App*>(user);
   if (a->window == nullptr) return G_SOURCE_REMOVE;

src/ui_source.cpp

@@ -6,6 +6,8 @@
 
 #include <adwaita.h>
 
+#include <cstdio>
+
 namespace udpscope {
 namespace ui_impl {
 
@@ -14,7 +16,11 @@ void build_source_panels(App& app) {
   SourceKind* kind = find_kind(app.source_kind);
   if (kind == nullptr) return;
   for (const SourcePanel& p : kind->make_panels(*app.acq->source())) {
-    if (p.widget == nullptr || p.id.empty()) continue;
+    if (p.widget == nullptr || p.id.empty()) {
+      std::fprintf(stderr, "[source] a '%s' panel was skipped: it has %s\n", app.source_kind.c_str(),
+                   p.widget == nullptr ? "no widget" : "an empty id");
+      continue;
+    }
     // Each page scrolls on its own, like Measure and Signals: panels differ in height.
     GtkWidget* scroller = gtk_scrolled_window_new();
     gtk_scrolled_window_set_policy(GTK_SCROLLED_WINDOW(scroller), GTK_POLICY_NEVER,