v1.7.1: accept EOFError as clean end-of-stream (newer libsigrokdecode)

Newer libsigrokdecode signals end-of-capture from wait() by raising
EOFError("samples exhausted"); Linux 0.5.3 instead returns None / raises
SystemError, so this only reproduced on Windows.  The framework explicitly
accepts EOFError out of decode() as normal termination, but decode() caught
it in the generic except Exception handler -- printing a traceback, logging
DECODE ERROR, and resyncing up to 50 times, which flooded the log at the end
of every capture.

- decode() and the five "except SystemError: raise" guards now use
  "except (SystemError, EOFError): raise", letting the end-of-stream signal
  propagate for a clean exit.  The critical guard is
  _measure_clock_period(), whose try wraps a wait() loop.
- 2 new unit tests assert decode() re-raises EOFError and SystemError.
- 67/67 unit tests; test_8/test_7/xiaomi_phone unchanged (Linux path).
  VERSION -> 1.7.1.

AGENTS.md

@@ -304,6 +304,29 @@ Known limitation: no on-disk fixture reproduces the exact live failure (all
 real captures contain a 372 ATR), so end-to-end proof needs a re-captured
 `.sr` from the failing phone; the unit tests cover the loop-escape logic.
 
+### v1.7.1: accept EOFError as clean end-of-stream (newer libsigrokdecode)
+
+Newer libsigrokdecode signals end-of-capture from `wait()` by raising
+`EOFError("samples exhausted")`; the 0.5.3 build on the Linux dev box instead
+returns `None` / raises `SystemError`, so this only showed up on Windows (a
+newer libsigrokdecode).  The framework explicitly accepts `EOFError` out of
+`decode()` as normal termination (`instance.c`: "Termination with an
+EOFError exception is accepted"), but our `decode()` caught it in the generic
+`except Exception` handler, printing a traceback, logging `DECODE ERROR`, and
+resyncing -- retrying up to 50 times and flooding the log (looked like a
+crash) at the end of every capture.
+
+- `decode()` and the five `except SystemError: raise` guards now use
+  `except (SystemError, EOFError): raise`, so the end-of-stream signal
+  propagates and libsigrokdecode terminates cleanly.  The critical guard is
+  `_measure_clock_period()`, whose `try` wraps a `wait()` loop.
+- 2 new unit tests assert `decode()` re-raises `EOFError` and `SystemError`.
+- 67/67 unit tests.  VERSION -> 1.7.1.
+
+Deployment note: the Windows decoder is a git clone, so `git pull` there
+(and deleting `__pycache__`) picks this up; the EOF error cannot be
+reproduced against Linux 0.5.3.
+
 ### v1.7.0: spurious end-of-decode hardening + start.sh session resilience
 
 A live capture could end without Ctrl+C (the session simply stopped).  The
@@ -607,7 +630,7 @@ official gsmtap.h reserves — a simtrace2-sniff convention.
 
 ### Versioning
 
-The decoder version is defined in `pd.py` as `VERSION = '1.7.0'`.
+The decoder version is defined in `pd.py` as `VERSION = '1.7.1'`.
 The version is printed to the log on decoder startup.
 
 ### Testing after decoder changes

pd.py

@@ -28,7 +28,7 @@ from .gsmtap_stream import (GsmtapStreamSender,
     GSMTAP_SIM_RST_EVENT, GSMTAP_SIM_VCC_EVENT,
     GSMTAP_FLAG_BAD_FCS)
 
-VERSION = '1.7.0'
+VERSION = '1.7.1'
 
 
 
@@ -807,7 +807,7 @@ class Decoder(srd.Decoder):
                 wes = max(self.es, wss + 1)
                 self.put(wss, wes, self.out_ann,
                          [Ann.ANN_WARN, ["noisy signal"]])
-            except SystemError:
+            except (SystemError, EOFError):
                 raise
             except Exception:
                 pass
@@ -856,7 +856,7 @@ class Decoder(srd.Decoder):
                 self._samples_per_clock = period
                 self.log("clock period (samples):", period)
                 return True
-        except SystemError:
+        except (SystemError, EOFError):
             raise
         except Exception:
             pass
@@ -1235,7 +1235,7 @@ class Decoder(srd.Decoder):
                 try:
                     self.put(self.ss, self.samplenum, self.out_ann,
                              [Ann.ANN_WARN, ["I/O stuck low?"]])
-                except SystemError:
+                except (SystemError, EOFError):
                     raise
                 except Exception:
                     pass
@@ -1346,7 +1346,7 @@ class Decoder(srd.Decoder):
                 try:
                     self.put(self.ss, self.samplenum, self.out_ann,
                              [Ann.ANN_WARN, ["I/O stuck low?"]])
-                except SystemError:
+                except (SystemError, EOFError):
                     raise
                 except Exception:
                     pass
@@ -1520,7 +1520,7 @@ class Decoder(srd.Decoder):
                     try:
                         self.put(self.ss, self.samplenum, self.out_ann,
                                  [Ann.ANN_WARN, ["I/O stuck low?"]])
-                    except SystemError:
+                    except (SystemError, EOFError):
                         raise
                     except Exception:
                         pass
@@ -2586,14 +2586,17 @@ class Decoder(srd.Decoder):
             while True:
                 # Crash protection: garbage from a noisy live signal must
                 # never kill the whole sigrok-cli process.  Log, warn and
-                # resync.  SystemError from wait() is the end-of-sample-
-                # stream signal and must propagate for a clean exit;
-                # KeyboardInterrupt (Ctrl+C) likewise passes through.
+                # resync.  End-of-sample-stream must propagate for a clean
+                # exit: older libsigrokdecode raises SystemError from
+                # put()/wait(), newer versions raise EOFError('samples
+                # exhausted') from wait() -- libsigrokdecode accepts either
+                # as normal decode() termination.  KeyboardInterrupt
+                # (Ctrl+C) likewise passes through.
                 try:
                     if (not self.decode_step()):
                         break
                     failures = 0
-                except SystemError:
+                except (SystemError, EOFError):
                     raise
                 except Exception as e:
                     traceback.print_exc(file=sys.stderr)
@@ -2603,7 +2606,7 @@ class Decoder(srd.Decoder):
                         wes = max(self.es, wss + 1)
                         self.put(wss, wes, self.out_ann,
                                  [Ann.ANN_WARN, ["decode error, resynced"]])
-                    except SystemError:
+                    except (SystemError, EOFError):
                         raise
                     except Exception:
                         pass

tests/test_gsmtap.py

@@ -530,5 +530,37 @@ class TestAtEof(unittest.TestCase):
         self.assertTrue(self.inst._at_eof())
 
 
+class TestEndOfStream(unittest.TestCase):
+    """decode() must let end-of-stream exceptions propagate.
+
+    Newer libsigrokdecode signals end-of-capture from wait() with
+    EOFError('samples exhausted') (older versions use SystemError).
+    libsigrokdecode accepts either as normal decode() termination, so
+    swallowing them turns a clean end into a flood of DECODE ERROR retries.
+    """
+
+    def setUp(self):
+        _, pd = _load_iso7816()
+        self.pd = pd
+
+    def _decode_raising(self, exc_cls):
+        inst = object.__new__(self.pd.Decoder)
+        inst.write_pcap_header = lambda: None
+        inst.finish = lambda: None
+
+        def step():
+            raise exc_cls('samples exhausted')
+        inst.decode_step = step
+        return inst
+
+    def test_eoferror_propagates(self):
+        with self.assertRaises(EOFError):
+            self._decode_raising(EOFError).decode()
+
+    def test_systemerror_propagates(self):
+        with self.assertRaises(SystemError):
+            self._decode_raising(SystemError).decode()
+
+
 if __name__ == '__main__':
     unittest.main()