[WIP] Throw Exception if results directory cannot be created or file cannot be written

[tkuchida]

Fixes #2181.

Brief summary of changes

• Catch errno == ENOENT if results directory cannot be created.
• Throw Exception from Storage if file cannot be opened for writing.

Testing I've completed

Ran example setup file that attempted to write results to C:\Program Files:

InverseKinematicsTool Failed: Storage: Failed to open file 'C:\Program Files/ik_marker_errors.sto' for writing.
Verify that the destination directory is writable.
        Thrown at Storage.cpp:2746 in print().

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CHANGELOG.md (choose one)

• no need to update because... bug fix.
• updated...

The Doxygen for this PR can be viewed at http://myosin.sourceforge.net/?C=N;O=D; click the folder whose name is this PR's number.

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This change is 

[chrisdembia]

Would it make sense to put the check OPENSIM_THROW_IF(errno == ENOENT, UnableToCreateDirectory, aDir); inside IO::makeDir()?

[chrisdembia]

The line number in this exception from the AppVeyor log is suspicious:

Exception:
4466  Unable to create directory 'twoMusclesOnBlock_ResultsCMC'.
4467  Thrown at CMCTool.cpp:831 in run().
4468  line= 1978645904

I don't think any of our source code files have that many lines.

[tkuchida]

@aseth1 Do you want these exceptions thrown from IO.cpp instead , or are there scenarios in which a consumer would want to notify the user but proceed anyway ? (Edit: a caller could still try/catch the exception if it has a way of recovering from the error.)

[tkuchida]

The line number in this exception from the AppVeyor log is suspicious:

I added the UnableToCreateDirectory exception following the example of FileIsEmpty and AFAIK I'm calling it the same way, so if UnableToCreateDirectory is wrong then the other Exceptions in FileAdapter.h may be wrong as well. This is a separate issue and is not responsible for the tests failing.

[tkuchida]

Would it make sense to put the check OPENSIM_THROW_IF(errno == ENOENT, UnableToCreateDirectory, aDir); inside IO::makeDir()?

It depends what you mean by "would it make sense". The current interface of IO::makeDir() is the following:

opensim-core/OpenSim/Common/IO.cpp

Lines 467 to 470 in 671076b

	/**
	* Create a directory. Potentially platform dependent.
	* @return int 0 on success, EEXIST or other error condition
	*/

so it seems like the problem is that the callers are ignoring the return value/error condition, not that makeDir() has been implemented incorrectly.