Minimake

Project Overview

Minimake is a simplified but fully functional version of the iconic UNIX tool GNU Make. The objective was to interpret a Makefile, construct a dependency graph, and execute the necessary commands to build a target.
Grade achieved: 90% (Excellent handling of recursion and parsing logic).

Technical Challenges

The heart of Minimake lies in its ability to determine what needs to be rebuilt and when. This involved:

• DAG Resolution: Dependencies form a Directed Acyclic Graph. I implemented a recursive algorithm to traverse the tree and build prerequisites first.
• Timestamp Logic: Using system calls (stat) to compare modification times between targets and dependencies, ensuring optimal builds (only rebuilding outdated files).
• Parsing Engine: Reading Makefiles line by line, identifying rules, variable assignments (recursive and simple expansion), and comments.

Implemented Features

Feature	Implementation Detail
Variables	Support for variable expansion ($(VAR)) and environment variables lookup.
Rules & Recipes	Execution of shell commands using fork and exec, handling return codes to stop execution on error.
Advanced Rules	Support for Phony targets (.PHONY) and Pattern rules (e.g., %.o: %.c) using wildcard matching.
Logic	Handling "Up to date" and "Nothing to be done" states correctly to avoid redundant compilations.

Conclusion

Scoring 90% on this project validated my understanding of graph theory applied to system programming. Minimake is now capable of building its own project, a "self-hosting" capability that demonstrates its robustness.