csv-core

A fast CSV reader and write for use in a no_std context. This crate will never use the Rust standard library.

Dual-licensed under MIT or the UNLICENSE.

Documentation

https://docs.rs/csv-core

Usage

Add this to your Cargo.toml:

toml [dependencies] csv-core = "0.1.6"

Build features

This crate by default links with libc, which is done via the libc feature. Disabling this feature will drop csv-core's dependency on libc.

Example: reading CSV

This example shows how to count the number of fields and records in CSV data.

```rust use csv_core::{Reader, ReadFieldResult};

let data = " foo,bar,baz a,b,c xxx,yyy,zzz ";

let mut rdr = Reader::new(); let mut bytes = data.asbytes(); let mut countfields = 0; let mut countrecords = 0; loop { // We skip handling the output since we don't need it for counting. let (result, nin, _) = rdr.readfield(bytes, &mut [0; 1024]); bytes = &bytes[nin..]; match result { ReadFieldResult::InputEmpty => {}, ReadFieldResult::OutputFull => panic!("field too large"), ReadFieldResult::Field { recordend } => { countfields += 1; if recordend { countrecords += 1; } } ReadFieldResult::End => break, } } asserteq!(3, countrecords); asserteq!(9, countfields); ```

Example: writing CSV

This example shows how to use the Writer API to write valid CSV data. Proper quoting is handled automatically.

```rust use csv_core::Writer;

// This is where we'll write out CSV data. let mut out = &mut [0; 1024]; // The number of bytes we've written to out. let mut nout = 0; // Create a CSV writer with a default configuration. let mut wtr = Writer::new();

// Write a single field. Note that we ignore the WriteResult and the number // of input bytes consumed since we're doing this by hand. let (_, _, n) = wtr.field(&b"foo"[..], &mut out[nout..]); nout += n;

// Write a delimiter and then another field that requires quotes. let (, n) = wtr.delimiter(&mut out[nout..]); nout += n; let (, , n) = wtr.field(&b"bar,baz"[..], &mut out[nout..]); nout += n; let (, n) = wtr.terminator(&mut out[nout..]); nout += n;

// Now write another record. let (, _, n) = wtr.field(&b"a \"b\" c"[..], &mut out[nout..]); nout += n; let (, n) = wtr.delimiter(&mut out[nout..]); nout += n; let (_, _, n) = wtr.field(&b"quux"[..], &mut out[nout..]); nout += n;

// We must always call finish once done writing. // This ensures that any closing quotes are written. let (_, n) = wtr.finish(&mut out[nout..]); nout += n;

assert_eq!(&out[..nout], &b"\ foo,\"bar,baz\" \"a \"\"b\"\" c\",quux"[..]); ```