INI Config Reader

Project roadmap

1. 01

   Set up the project

   ~1h

   Create src/main.c and a Makefile that compiles with -Wall -Wextra -std=c11 and has build, clean and test targets. Add example files to examples/: a valid config with two sections and several keys, and one with mistakes. The program prints usage when started with no arguments. Done when: make builds the program and running it without arguments prints the usage.

2. 02

   Read the file line by line

   ~1.5h

   Open the file with fopen and read it line by line with fgets into a buffer (lines up to 512 characters). Write a trim function that removes leading and trailing spaces and the newline. Skip empty lines and comment lines starting with ; or #. Print an error and exit with code 1 if the file can't be opened. Done when: the program prints every meaningful line of the example file, trimmed.

3. 03

   Parse sections and keys

   ~2h

   Recognize [section] lines and key = value lines, trimming spaces around the key and value. Store entries in an array of structs with section, key and value fields (fixed-size char arrays are fine), growing the array with realloc when needed. Done when: after parsing the valid example, the program holds every entry with the right section.

4. 04

   Report errors with line numbers

   ~1.5h

   Report problems as file:line: message: a line that is neither a section nor key = value, a key before any section, an empty key, a section header without the closing ], and a duplicate key within the same section. Collect all errors instead of stopping at the first, and exit with code 1 when any are found. Done when: the broken example prints each mistake with its correct line number.

5. 05

   Add the commands

   ~1.5h

   Support three commands: iniread FILE SECTION KEY prints the value (exit code 2 if it isn't found), iniread FILE --list prints every entry as section.key = value, and iniread FILE --check prints OK or the errors. Section and key names are compared without regard to upper or lower case. Done when: all three commands work on the example files.

6. 06

   Test it

   ~1.5h

   Write tests/run.sh, called by make test, that runs the program on the example files and compares its output and exit codes with expected results. Cover: getting a value, a missing key, listing, and each kind of error. Done when: make test passes.

Resources

• ArticleINI file format (Wikipedia)
• DocsC reference (cppreference)
• Docsfgets reference
• DocsGNU Make manual