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os.getcwd() was called eagerly as the default= value of the -out argument, which is evaluated when add_argument() is called, not when the argument is actually absent from the command line. If the process CWD has been deleted (e.g. during pytest runs inside a package manager sandbox), this raises FileNotFoundError before any test body runs. Move the os.getcwd() call to the assignment site (results_directory), where it is only reached after parse_args() succeeds and only when -out was not supplied by the caller.
The binwalk scan helper does os.chdir(tmpdirname) to work around binwalk's lack of an output-directory option. It saves and restores the CWD using os.getcwd() / os.chdir(saved_dir). Two problems with this approach: 1. os.getcwd() raises FileNotFoundError if a previous test left the process in a since-deleted temp directory. 2. binwalk uses multiprocessing internally; the spawned child process inherits the parent's CWD (tmpdirname). On some platforms/configs Python's multiprocessing.spawn serialises the CWD and tries to restore it in the child. If tmpdirname is deleted between the spawn and the child starting, spawn.py raises FileNotFoundError. Fix: open the current directory as an O_RDONLY fd before chdir'ing, then restore with os.fchdir(). An open fd keeps the inode alive even if the path is later removed, and fchdir never has to resolve a path. If the initial open fails (CWD already gone), fall back to self.results_directory which is always a valid path at this point.
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Problems
Two separate
FileNotFoundErrorcrash sites were found while packaging stegoveritas for Pentoo Linux:pentoo/pentoo-overlay#2923
1.
add_argumentdefault evaluated eagerly (line 179)Python evaluates
default=whenadd_argument()is called, not when-outis absent. If the process CWD has been deleted at that point,os.getcwd()raisesFileNotFoundErrorbefore any test body runs.Fix: use
default=Noneand resolve lazily at theresults_directoryassignment site.2.
os.getcwd()/os.chdir()in binwalk scan path (line 98)Two issues here:
os.getcwd()fails immediately.multiprocessinginternally. On some platforms Python'smultiprocessing.spawnserialises the parent CWD and tries to restore it in the child. Iftmpdirnameis removed between spawn and child startup,spawn.pyraisesFileNotFoundError.Fix: save the current directory as an
O_RDONLYfd withos.open('.')and restore withos.fchdir(). An open fd keeps the inode alive even if the path is later unlinked, andfchdirnever has to resolve a path. Fall back toself.results_directoryif the initialopenfails (CWD already gone).Note: a separate failure (
AttributeError: module 'capstone' has no attribute 'CS_ARCH_ARM64') is caused by a capstone 5.x API change inbinwalk/modules/disasm.pyand is outside the scope of this PR.