Move stdin processing to yield()
#32
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bxparks
reviewed
Jul 14, 2021
| @@ -22,6 +22,11 @@ | |||
| // ----------------------------------------------------------------------- | |||
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| void yield() { | |||
| char c = '\0'; | |||
| if (read(STDIN_FILENO, &c, 1) == 1) { | |||
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Thanks for the fix. Just out of curiosity, how did you hit this bug? Sending a NUL character into the Serial port seems like a rare thing.. unless you were sending binary data?
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I didn't actually run into that bug. I was fixing the unused result compiler warning and noticed that it would also fix the NUL issue.
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The strange thing is that I have both -Wall and -Wextra enabled by default. According to the documentations I see online, those imply -Wunused-result which should warn me about this. But neither g++ nor clang++ on Linux (Ubuntu 20.04) will trigger a warning for me.
Anyway, I will merge this.
Before this patch, stdin is only read between calls to loop(). This causes problems when a program waits for serial input while calling yield() in a loop. Moving the stdin handling code to yield() fixes this problem and more closely matches real hardware behavior. Also, this patch checks the return value from read(), which fixes a compiler warning and allows null bytes to be read correctly.
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Before this patch, stdin is only read between calls to
loop(). This causes problems when a program waits for serial input while callingyield()in a loop. Moving the stdin handling code toyield()fixes this problem and more closely matches real hardware behavior.Also, this patch checks the return value from
read(), which fixes a compiler warning and allows null bytes to be read correctly.