From 0d830bad59c0d2d9d105c0ac3a2cec616aebef17 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Fredrik=20=C3=96hrstr=C3=B6m?= <oehrstroem@gmail.com>
Date: Sun, 8 Aug 2021 23:07:34 +0200
Subject: [PATCH] Fix bug that caused crash when dongle was reset.

---
 Makefile             |  4 ++--
 src/serial.cc        |  8 ++++++--
 src/serial.h         |  1 +
 src/util.cc          |  2 +-
 src/wmbus_amb8465.cc | 12 +++++++++++-
 5 files changed, 21 insertions(+), 6 deletions(-)

diff --git a/Makefile b/Makefile
index fc4b23f..216ea97 100644
--- a/Makefile
+++ b/Makefile
@@ -47,8 +47,8 @@ ifeq "$(DEBUG)" "true"
         GCOV?=gcov
     endif
 else
-    DEBUG_FLAGS=-Os
-    STRIP_BINARY=$(STRIP) $(BUILD)/wmbusmeters
+    DEBUG_FLAGS=-Os -g
+    STRIP_BINARY=echo FOO
     GCOV=To_run_gcov_add_DEBUG=true
 endif
 
diff --git a/src/serial.cc b/src/serial.cc
index c57d293..adbead7 100644
--- a/src/serial.cc
+++ b/src/serial.cc
@@ -146,6 +146,7 @@ struct SerialDeviceImp : public SerialDevice
     int receive(vector<uchar> *data);
     bool waitFor(uchar c);
     bool working() { return resetting_ || fd_ != -1; }
+    bool resetting() { return resetting_; }
     bool opened() { return resetting_ || fd_ != -2; }
     bool isClosed() { return fd_ == -1 && !resetting_; }
     bool readonly() { return is_stdin_ || is_file_; }
@@ -958,8 +959,11 @@ void *SerialCommunicationManagerImp::eventLoop()
             {
                 if (sd->opened() && sd->working() && !sd->skippingCallbacks())
                 {
-                    trace("[SERIAL] select read on fd %d\n", sd->fd());
-                    FD_SET(sd->fd(), &readfds);
+                    if (!sd->resetting() && sd->fd() >= 0)
+                    {
+                        trace("[SERIAL] select read on fd %d\n", sd->fd());
+                        FD_SET(sd->fd(), &readfds);
+                    }
                 }
                 if (sd->opened() && !sd->working()) all_working = false;
             }
diff --git a/src/serial.h b/src/serial.h
index ba66172..cd5c7da 100644
--- a/src/serial.h
+++ b/src/serial.h
@@ -53,6 +53,7 @@ struct SerialDevice
     virtual int fd() = 0;
     virtual bool opened() = 0;
     virtual bool working() = 0;
+    virtual bool resetting() = 0; // The serial device is working but can lack a valid file descriptor.
     // Used when connecting stdin to a tty driver for testing.
     virtual bool readonly() = 0;
     // Mark this device so that it is ignored by the select/callback event loop.
diff --git a/src/util.cc b/src/util.cc
index a26c80c..1dd35e6 100644
--- a/src/util.cc
+++ b/src/util.cc
@@ -1952,5 +1952,5 @@ size_t findBytes(vector<uchar> &v, uchar a, uchar b, uchar c)
         }
         p++;
     }
-    return 0;
+    return (size_t)-1;
 }
diff --git a/src/wmbus_amb8465.cc b/src/wmbus_amb8465.cc
index c1e964f..795d6c4 100644
--- a/src/wmbus_amb8465.cc
+++ b/src/wmbus_amb8465.cc
@@ -55,6 +55,11 @@ struct ConfigAMB8465
         return ids;
     }
 
+    bool enoughBytes(vector<uchar> &bytes, size_t offset)
+    {
+        return false;
+    }
+
     bool decode(vector<uchar> &bytes)
     {
         size_t o = 5;
@@ -612,6 +617,11 @@ AccessCheck detectAMB8465(Detected *detected, shared_ptr<SerialCommunicationMana
             continue;
         }
         response.insert(response.end(), data.begin(), data.end());
+        //size_t skip = findBytes(response, 0xff, 0x8A, 0x7A);
+        /*if (skip == ((size_t)-1) || (response.size()-skip)
+        {
+
+        }*/
     }
 
     serial->close();
@@ -620,7 +630,7 @@ AccessCheck detectAMB8465(Detected *detected, shared_ptr<SerialCommunicationMana
 
     size_t skip = findBytes(response, 0xff, 0x8A, 0x7A);
     debug("(amb8465) skipping %zu bytes\n", skip);
-    while (skip > 0)
+    while (skip > 0 && skip != ((size_t)-1))
     {
         // Sometimes there seems to be a leading 00 noise byte. Skip those.
         response.erase(response.begin());