Buffered file stream doesn't flush data right

[emayevski]

Description

In BufferedFileStreamStrategy.cs, the Flush(bool flushToDisk) method does not perform flushing to disk when flushToDisk == true and there is data in the read or write buffer. I.e., both conditional blocks marked as "// Has write data ..." and "// Has read data ... " return without calling the underlying strategy's flush(flushToDisk).

Reproduction Steps

No simple reproduction is available but the problem is obvious from the method itself.

Expected behavior

The underlying strategy's flush(flushToDisk) must be called in all cases.

Actual behavior

As described above.

Regression?

No response

Known Workarounds

Setting the buffer size to 0 causes no buffering and correct flushing. But this is not really a workaround since it requires disabling of buffering.

Configuration

.NET 6.

Other information

No response

[dotnet-issue-labeler]

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[emayevski]

This belongs to area-System.IO

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Issue Details

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Description

In BufferedFileStreamStrategy.cs, the Flush(bool flushToDisk) method does not perform flushing to disk when flushToDisk == true and there is data in the read or write buffer. I.e., both conditional blocks marked as "// Has write data ..." and "// Has read data ... " return without calling the underlying strategy's flush(flushToDisk).

Reproduction Steps

No simple reproduction is available but the problem is obvious from the method itself.

Expected behavior

The underlying strategy's flush(flushToDisk) must be called in all cases.

Actual behavior

As described above.

Regression?

No response

Known Workarounds

Setting the buffer size to 0 causes no buffering and correct flushing. But this is not really a workaround since it requires disabling of buffering.

Configuration

.NET 6.

Other information

No response

Author:	emayevski
Assignees:	-
Labels:	area-System.IO, untriaged
Milestone:	-

[adamsitnik]

Hi @emayevski

Big thanks for a detailed bug report! I've sent a fix: #77384

Setting the buffer size to 0 causes no buffering and correct flushing. But this is not really a workaround since it requires disabling of buffering.

Another workaround is to call this this method twice (I know it's dirty).

[emayevski]

Thank you!

The workaround is good too :).