csv_parser

A simple C library for parsing CSV.

License: MIT

Overview

csv.c: Parse a single line of CSV (a string with no unescaped linebreaks)

split.c: Split a string of CSV (with unescaped linebreaks) into single lines of CSV

fread_csv_line.c: Extract a single line of CSV from a file

Documentation (csv.c)

char **parse_csv( const char *line );

Returns a NULL-terminated array of strings encoded in the indicated line of CSV.

Returns NULL if there was insufficient RAM or if the line is not property encoded CSV.

The return value of parse_csv is malloc'd. Each string in the array is also malloc'd.

void free_csv_line( char **parsed );

Convenience function to free the parse_csv output. Frees each string in the array and then frees the array.

Documentation (split.c)

char **split_on_unescaped_newlines(const char *txt);

Given a string, which might contain unescaped linebreaks, get a NULL-terminated array of strings, each of which does not contain unescaped linebreaks.

Both the array and the strings in the array are malloc'd.

Documentation (fread_csv_line.c)

char *fread_csv_line(FILE *fp, int max_line_size, int *done, int *err)

Extract a line of CSV from a file.

max_line_size: Lines longer than this will cause fread_csv_line to return NULL.

done: Pointer to an int. The int is set to 1 when the end of fp is reached.

err: Pointer to an int. On error, an error code will be written to this int. Error codes are defined in csv.h: CSV_ERR_LONGLINE and CSV_ERR_NO_MEMORY.

Caveats

fread_csv_line is optimized for repeating until the file is exhausted. It mutates/depends on file position (in the fseek sense), in an unpredictable way.

fread_csv_line shouldn't be called on different files in parallel. (Hopefully sometime in the future we'll add a proper init system to deal with this).

Calling fread_csv_line on fp after a previous call exhausted the file (indicated by *done) is undefined behavior.

TODO

In split.c and fread_csv_line.c: Deal with carriage returns when "linebreak" doesn't mean "\n"