Fix file descriptor leak in FileIO instrumentation

[ntoskrnl]

📜 Description

There is a bug in FileIO tracing that causes leak in file descriptors.
The bug affects Android and Java.

💡 Motivation and Context

The context and all the information is here.

When we create new SentryFileInputStream(file) or new SentryFileOutputStream(file), 2 file descriptors are opened. But when we close the stream, only one is closed. The cause is in this comment.

💚 How did you test it?

Run the code below in the sample app. Before fix I see lsof still shows 10 open files even though they are closed. After fix - nothing shows up.

// write into several files with SentryFileOutputStream, close and delete them.
ExecutorService executor = Executors.newSingleThreadExecutor();
for (int i = 0; i < 10; i++) {
  final String name = "my-test-file-" + i + ".bin";
  executor.submit(
    () -> {
      File file = new File(name);
      try (FileOutputStream out = new SentryFileOutputStream(file, false)) {
        out.write("Hello world!".getBytes(StandardCharsets.UTF_8));
        out.flush();
        Thread.sleep(50);
      } catch (Exception error) {
        // ignore
      }
      file.delete();
    }
  );
}

// run "lsof" and check if they are still open
executor.submit(
  () -> {
    try {
      StringBuilder output = new StringBuilder();
      Process process = Runtime.getRuntime().exec("lsof");
      BufferedReader reader = new BufferedReader(new InputStreamReader(process.getInputStream()));
      while (true) {
        String line = reader.readLine();
        if (line == null) break;
        if (line.contains("my-test-file-")) {
          output.append(line);
          output.append("\n");
        }
      }
      System.out.println("> slof \n" + output);
      process.destroy();
    } catch (IOException e) {
      // ignore
    }
  }
);

executor.shutdown();

📝 Checklist

• I reviewed the submitted code
• I added tests to verify the changes
• I updated the docs if needed
• No breaking changes

[adinauer]

LGTM. Thank you very much for fixing this bug!

[codecov-commenter]

Codecov Report

Base: 80.64% // Head: 80.62% // Decreases project coverage by -0.02% ⚠️

Coverage data is based on head (5986588) compared to base (429f878).
Patch coverage: 50.00% of modified lines in pull request are covered.

❗ Current head 5986588 differs from pull request most recent head d1a390b. Consider uploading reports for the commit d1a390b to get more accurate results

Additional details and impacted files

@@             Coverage Diff              @@
##               main    #2248      +/-   ##
============================================
- Coverage     80.64%   80.62%   -0.03%     
- Complexity     3366     3368       +2     
============================================
  Files           240      240              
  Lines         12382    12388       +6     
  Branches       1646     1646              
============================================
+ Hits           9986     9988       +2     
- Misses         1787     1791       +4     
  Partials        609      609              

Impacted Files	Coverage Δ
...ry/instrumentation/file/SentryFileInputStream.java	65.95% <50.00%> (-2.23%)	⬇️
...y/instrumentation/file/SentryFileOutputStream.java	45.45% <50.00%> (-0.70%)	⬇️

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