Agent will not run on Linux if profiler log path contains non-existing intermediate paths

[nr-ahemsath]

Description

By default, the native profiler component of the agent logs to $NEW_RELIC_HOME/Logs (or $NEW_RELIC_HOME/logs on Linux). This location can be overridden with the environment variable NEWRELIC_PROFILER_LOG_DIRECTORY. On Windows, any non-existing components of the path supplied in this variable will be created (assuming the process being instrumented is running with sufficient permissions to do so). For example:

C:\existingDir <- exists
C:\existingDir\nonExistingDir <- doesn't exist
NEWRELIC_PROFILER_LOG_DIRECTORY=C:\existingDir\nonExistingDir\profilerLogs

then C:\existingDir\nonExistingDir will be created as part of the process of creating the profiler log directory.

On Linux, this doesn't work. Only the final component of the path can be automatically created.

NEWRELIC_PROFILER_LOG_DIRECTORY=/home/user/existingDir/profilerLogs <- works
NEWRELIC_PROFILER_LOG_DIRECTORY=/home/user/nonExistingDir/profilerLogs <- doesn't work

NOTE: this problem blocks the profiler from initializing, which means that the agent will not run.

The cause appears to be that on Windows, the system call used to create the profiler log directory is SHCreateDirectoryExW, which automatically creates intermediate path components: https://docs.microsoft.com/en-us/windows/win32/api/shlobj_core/nf-shlobj_core-shcreatedirectoryexw

whereas on Linux, the system call used is mkdir, which doesn't: https://man7.org/linux/man-pages/man2/mkdir.2.html (under errors, see "ENOENT: A directory component in pathname does not exist")

Expected Behavior
The behavior of the agent should be consistent between Windows and Linux.

See this Stack Overflow discussion on how to make a version of mkdir that automatically creates intermediate path components: https://stackoverflow.com/questions/2336242/recursive-mkdir-system-call-on-unix

[angelatan2]

Size = S