DataFlash: create a WritesOK method for WritePrioritisedBlock

libraries/DataFlash/DataFlash_Backend.cpp

@@ -259,3 +259,11 @@ bool DataFlash_Backend::Log_Write(const uint8_t msg_type, va_list arg_list, bool
 
     return WritePrioritisedBlock(buffer, msg_len, is_critical);
 }
+
+bool DataFlash_Backend::WritesOK() const
+{
+    if (!_writes_enabled) {
+        return false;
+    }
+    return true;
+}

libraries/DataFlash/DataFlash_Backend.h

@@ -140,6 +140,8 @@ protected:
                           print_mode_fn print_mode,
                           AP_HAL::BetterStream *port);
 
+    virtual bool WritesOK() const;
+
     bool _writes_enabled = false;
 
     /*

libraries/DataFlash/DataFlash_Block.cpp

@@ -42,13 +42,27 @@ void DataFlash_Block::FinishWrite(void)
     df_BufferIdx = 0;
 }
 
+bool DataFlash_Block::WritesOK() const
+{
+    if (!DataFlash_Backend::WritesOK()) {
+        return false;
+    }
+    if (!CardInserted()) {
+        return false;
+    }
+    if (!log_write_started) {
+        return false;
+    }
+    return true;
+}
+
 bool DataFlash_Block::WritePrioritisedBlock(const void *pBuffer, uint16_t size,
     bool is_critical)
 {
     // is_critical is ignored - we're a ring buffer and never run out
     // of space.  possibly if we do more complicated bandwidth
     // limiting we can reservice bandwidth based on is_critical
-    if (!CardInserted() || !log_write_started || !_writes_enabled) {
+    if (!WritesOK()) {
         return false;
     }
 

libraries/DataFlash/DataFlash_Block.h

@@ -13,7 +13,7 @@ public:
     DataFlash_Block(DataFlash_Class &front, DFMessageWriter_DFLogStart *writer) :
         DataFlash_Backend(front, writer) { }
 
-    virtual bool CardInserted(void) = 0;
+    virtual bool CardInserted(void) const = 0;
 
     // erase handling
     void EraseAll();
@@ -115,6 +115,8 @@ protected:
     uint16_t df_NumPages;
 
     virtual void ReadManufacturerID() = 0;
+
+    bool WritesOK() const override;
 };
 
 

libraries/DataFlash/DataFlash_File.cpp

@@ -509,10 +509,27 @@ void DataFlash_File::EraseAll()
     }
 }
 
+bool DataFlash_File::WritesOK() const
+{
+    if (!DataFlash_Backend::WritesOK()) {
+        return false;
+    }
+    if (_write_fd == -1) {
+        return false;
+    }
+    if (!_initialised) {
+        return false;
+    }
+    if (_open_error) {
+        return false;
+    }
+    return true;
+}
+
 /* Write a block of data at current offset */
 bool DataFlash_File::WritePrioritisedBlock(const void *pBuffer, uint16_t size, bool is_critical)
 {
-    if (_write_fd == -1 || !_initialised || _open_error || !_writes_enabled) {
+    if (!WritesOK()) {
         return false;
     }
 

libraries/DataFlash/DataFlash_File.h

@@ -73,6 +73,10 @@ public:
 
     void vehicle_was_disarmed() override;
 
+protected:
+
+    bool WritesOK() const override;
+
 private:
     int _write_fd;
     int _read_fd;

libraries/DataFlash/DataFlash_MAVLink.cpp

@@ -118,12 +118,27 @@ bool DataFlash_MAVLink::free_seqno_from_queue(uint32_t seqno, dm_block_queue_t &
     return false;
 }
     
+
+bool DataFlash_MAVLink::WritesOK() const
+{
+    if (!DataFlash_Backend::WritesOK()) {
+        return false;
+    }
+    if (!_initialised) {
+        return false;
+    }
+    if (!_sending_to_client) {
+        return false;
+    }
+    return true;
+}
+
 /* Write a block of data at current offset */
 
 // DM_write: 70734 events, 0 overruns, 167806us elapsed, 2us avg, min 1us max 34us 0.620us rms
 bool DataFlash_MAVLink::WritePrioritisedBlock(const void *pBuffer, uint16_t size, bool is_critical)
 {
-    if (!_initialised || !_sending_to_client || !_writes_enabled) {
+    if (!WritesOK()) {
         return false;
     }
 

libraries/DataFlash/DataFlash_MAVLink.h

@@ -67,6 +67,10 @@ public:
 
     void remote_log_block_status_msg(mavlink_channel_t chan, mavlink_message_t* msg) override;
 
+protected:
+
+    bool WritesOK() const override;
+
 private:
 
     struct dm_block {

libraries/DataFlash/DataFlash_SITL.cpp

@@ -55,7 +55,7 @@ void DataFlash_SITL::ReadManufacturerID()
 	df_device = 0x0203;
 }
 
-bool DataFlash_SITL::CardInserted(void)
+bool DataFlash_SITL::CardInserted(void) const
 {
     return true;
 }

libraries/DataFlash/DataFlash_SITL.h

@@ -42,7 +42,7 @@ public:
         DataFlash_Block(front, writer) { }
     void        Init() override;
     void        ReadManufacturerID();
-    bool        CardInserted();
+    bool        CardInserted() const;
 };
 
 #endif // CONFIG_HAL_BOARD == HAL_BOARD_SITL