[gyf304]

* Memory allocation NULL check: this is a bona-fide bug introduced by my refactoring

* MAX_FILE_SIZE: I don't think this is true.

* skip_until_charset, skip_charset bound check bug: I don't think this is true

* Uninitialized value_end: I don't think this is true - and if true should be caught by -Wall -Werror flags.

* argc < 1 check not being necessary: This is not true, you can make argc == 0 by using the exec family of libc functions.

* Error Handling: Currently all parsing errors should cause the program to exit, which I think is the desired behavior.

* Unsanitized input for .env: Intended behavior.

* Unsanitized input for execvp: Intended behavior.