csvParser

A CSV parser is one of those things that looks trivial until the first file with a comma inside a quoted field arrives. This one exists because strtok() and strsep() kept producing awkward behaviour: they are stateful, they do not know about quoting, and once a separator appears inside quotes the parse is already wrong.

So instead of splitting strings with a library tokeniser, the parser walks the input itself and tracks CSV quoting state as it goes. That single decision is what makes quoted separators, multi-line cells and ragged rows fall out naturally rather than needing special cases.

Data structure

Parsing produces a linked list of rows, each holding a linked list of cells, and then a lookup array of row pointers is built on top. The array gives fast row access; the linked cells allow every row to hold a different number of columns.

Row 0 -> Cell 0 -> Cell 1 -> Cell 2
  |
Row 1 -> Cell 0 -> Cell 1 -> Cell 2 -> Cell 3
  |
Row 2 -> Cell 0 -> Cell 1

Access is then getCell(row, column), with cell status available for the three cases that actually bite in practice: an empty cell, a row that does not exist, and a column that does not exist in a row that does.

What it handles

• Custom separators, not just commas.
• Quoted fields containing the separator.
• Multi-line quoted cells.
• Ragged files, where rows have different numbers of columns.
• Files produced by Excel, which are RFC 4180-ish rather than strictly RFC 4180.

Scope, honestly

It reads the whole file into memory, so the maximum file size is bounded by available RAM. That is a deliberate trade: it keeps the structure simple and the access direct, and it is the wrong choice for a multi-gigabyte export. It also is not trying to replace a large feature-rich CSV library — if you need strict RFC 4180 conformance in every edge case, use one of those.

The repository runs super-linter, a C/C++ build workflow and CodeQL on every push, which matters more than usual for a parser: most of the interesting bugs in C are in the boundary handling.

Using it

There is no GUI and no package to install. Clone the repository, build it with the included C/C++ workflow, and link the source into your project — there is nothing else to pull in.