Input parsing and shell language

[jwoos]

• [x] space delimited
• [x] single and double quotations
• [x] proper argument delimiting
• [ ] redirection
• [ ] piping
• [ ] surrounding parentheses
• [ ] || and &&
• [ ] background jobs &
• [ ] Subset of shell language

[jwoos]

Structs were set up with #8 but it needs serious refactoring

[jwoos]

https://www.ibm.com/developerworks/library/l-lexyac/index.html

[jwoos]

~Flex for lexical analyzer and Bison for parser generator~

[jwoos]

Parse into AST for redirection, pipes, etc

Top down parser (LL1) for the actual shell language

• parse the grammar rules and store a table in memory on shell initialization