ext/fastcsv/fastcsv.rl
#include <ruby.h>
#include <ruby/encoding.h>
// CSV specifications.
// http://tools.ietf.org/html/rfc4180
// http://w3c.github.io/csvw/syntax/#ebnf
// CSV implementation.
// https://github.com/ruby/ruby/blob/trunk/lib/csv.rb
// Ruby C extensions help.
// https://github.com/ruby/ruby/blob/trunk/README.EXT
// http://rxr.whitequark.org/mri/source
// Ragel help.
// https://www.mail-archive.com/ragel-users@complang.org/
#define ENCODE \
if (enc2 != NULL) { \
field = rb_str_encode(field, rb_enc_from_encoding(enc), 0, Qnil); \
}
#define FREE \
if (buf != NULL) { \
free(buf); \
} \
if (row_sep != NULL) { \
free(row_sep); \
}
static VALUE cClass, cParser, eError;
static ID s_read, s_row;
// @see https://github.com/nofxx/georuby_c/blob/b3b91fd90980d7c295ac8f6012d89878ea7cd569/ext/types.h#L22
typedef struct {
char *start;
} Data;
%%{
machine raw_parse;
action open_quote {
unclosed_line = curline;
}
action close_quote {
unclosed_line = 0;
}
action read_unquoted {
if (p == ts) {
// Unquoted empty fields are nil, not "", in Ruby.
field = Qnil;
}
else if (p > ts) {
field = rb_enc_str_new(ts, p - ts, encoding);
ENCODE;
}
}
action read_quoted {
if (p == ts) {
field = rb_enc_str_new("", 0, encoding);
ENCODE;
}
// @note If we add an action on '""', we can skip some steps if no '""' is found.
else if (p > ts) {
// Operating on ts in-place produces odd behavior, FYI.
char *copy = ALLOC_N(char, p - ts);
memcpy(copy, ts, p - ts);
char *reader = ts, *writer = copy;
int escaped = 0;
while (p > reader) {
if (*reader == quote_char && !escaped) {
// Skip the escaping character.
escaped = 1;
}
else {
escaped = 0;
*writer++ = *reader;
}
reader++;
}
field = rb_enc_str_new(copy, writer - copy, encoding);
ENCODE;
if (copy != NULL) {
free(copy);
}
}
}
action new_field {
rb_ary_push(row, field);
field = Qnil;
}
action mark_row {
d->start = p;
if (len_row_sep) {
if (p - mark_row_sep != len_row_sep || row_sep[0] != *mark_row_sep || (len_row_sep == 2 && row_sep[1] != *(mark_row_sep + 1))) {
FREE;
rb_raise(eError, "Unquoted fields do not allow \\r or \\n (line %d).", curline);
}
}
else {
len_row_sep = p - mark_row_sep;
row_sep = ALLOC_N(char, len_row_sep);
memcpy(row_sep, mark_row_sep, len_row_sep);
}
curline++;
}
action new_row {
mark_row_sep = p;
if (d->start == 0 || p == d->start) {
rb_ivar_set(self, s_row, rb_str_new2(""));
}
else if (p > d->start) {
rb_ivar_set(self, s_row, rb_str_new(d->start, p - d->start));
}
if (!NIL_P(field) || RARRAY_LEN(row)) { // same as new_field
rb_ary_push(row, field);
field = Qnil;
}
rb_yield(row);
row = rb_ary_new();
}
action last_row {
if (d->start == 0 || p == d->start) { // same as new_row
rb_ivar_set(self, s_row, rb_str_new2(""));
}
else if (p > d->start) {
rb_ivar_set(self, s_row, rb_str_new(d->start, p - d->start));
}
if (!NIL_P(field) || RARRAY_LEN(row)) {
rb_ary_push(row, field);
}
if (RARRAY_LEN(row)) {
rb_yield(row);
}
}
EOF = 0;
quote_char = any when { fc == quote_char };
col_sep = any when { fc == col_sep } >new_field;
row_sep = '\r' '\n'? | '\n';
unquoted = (any* -- quote_char -- col_sep -- row_sep -- '\r' -- '\n' - EOF) %read_unquoted;
quoted = quote_char >open_quote (any - quote_char - EOF | quote_char quote_char)* %read_quoted quote_char >close_quote;
field = unquoted | quoted;
# @see Ragel Guide: 6.3 Scanners
# > Entering
# % Leaving
# An unquoted field can be zero-length.
main := |*
field col_sep;
field row_sep >new_row %mark_row;
field EOF >last_row;
*|;
}%%
%% write data;
// 16 kB
#define BUFSIZE 16384
// @see http://rxr.whitequark.org/mri/source/io.c#4845
static void rb_io_ext_int_to_encs(rb_encoding *ext, rb_encoding *intern, rb_encoding **enc, rb_encoding **enc2, int fmode) {
int default_ext = 0;
if (ext == NULL) {
ext = rb_default_external_encoding();
default_ext = 1;
}
if (ext == rb_ascii8bit_encoding()) {
/* If external is ASCII-8BIT, no transcoding */
intern = NULL;
}
else if (intern == NULL) {
intern = rb_default_internal_encoding();
}
if (intern == NULL || intern == (rb_encoding *)Qnil || intern == ext) {
/* No internal encoding => use external + no transcoding */
*enc = (default_ext && intern != ext) ? NULL : ext;
*enc2 = NULL;
}
else {
*enc = intern;
*enc2 = ext;
}
}
static VALUE raw_parse(int argc, VALUE *argv, VALUE self) {
int cs, act, have = 0, curline = 1, io = 0;
char *ts = 0, *te = 0, *buf = 0, *eof = 0, *mark_row_sep = 0, *row_sep = 0;
VALUE port, opts, r_encoding;
VALUE row = rb_ary_new(), field = Qnil, bufsize = Qnil;
int done = 0, unclosed_line = 0, buffer_size = 0, taint = 0, len_row_sep = 0;
rb_encoding *enc = NULL, *enc2 = NULL, *encoding = NULL;
Data *d;
Data_Get_Struct(self, Data, d);
VALUE option;
char quote_char = '"', col_sep = ',';
rb_scan_args(argc, argv, "11", &port, &opts);
taint = OBJ_TAINTED(port);
io = rb_respond_to(port, s_read);
if (!io) {
if (rb_respond_to(port, rb_intern("to_str"))) {
port = rb_funcall(port, rb_intern("to_str"), 0);
StringValue(port);
}
else {
rb_raise(rb_eArgError, "data has to respond to #read or #to_str");
}
}
if (NIL_P(opts)) {
opts = rb_hash_new();
}
else if (TYPE(opts) != T_HASH) {
rb_raise(rb_eArgError, "options has to be a Hash or nil");
}
option = rb_hash_aref(opts, ID2SYM(rb_intern("quote_char")));
if (TYPE(option) == T_STRING && RSTRING_LEN(option) == 1) {
quote_char = *StringValueCStr(option);
}
else if (!NIL_P(option)) {
rb_raise(rb_eArgError, ":quote_char has to be a single character String");
}
option = rb_hash_aref(opts, ID2SYM(rb_intern("col_sep")));
if (TYPE(option) == T_STRING && RSTRING_LEN(option) == 1) {
col_sep = *StringValueCStr(option);
}
else if (!NIL_P(option)) {
rb_raise(rb_eArgError, ":col_sep has to be a single character String");
}
// @see rb_io_extract_modeenc parse_mode_enc
/* Set to defaults */
rb_io_ext_int_to_encs(NULL, NULL, &enc, &enc2, 0);
// "enc" (internal) or "enc2:enc" (external:internal) or "enc:-" (external).
// We don't support binmode, which would force "ASCII-8BIT", or "BOM|UTF-*".
// @see http://ruby-doc.org/core-2.1.1/IO.html#method-c-new-label-Open+Mode
option = rb_hash_aref(opts, ID2SYM(rb_intern("encoding")));
if (TYPE(option) == T_STRING) {
// `parse_mode_enc` is not in header file.
const char *estr = StringValueCStr(option), *ptr;
char encname[ENCODING_MAXNAMELEN+1];
int idx, idx2;
rb_encoding *ext_enc, *int_enc;
/* parse estr as "enc" or "enc2:enc" or "enc:-" */
ptr = strrchr(estr, ':');
if (ptr) {
long len = (ptr++) - estr;
if (len == 0 || len > ENCODING_MAXNAMELEN) { // ":enc"
idx = -1;
}
else { // "enc2:enc" or "enc:-"
memcpy(encname, estr, len);
encname[len] = '\0';
estr = encname;
idx = rb_enc_find_index(encname);
}
}
else { // "enc"
idx = rb_enc_find_index(estr);
}
if (idx >= 0) {
ext_enc = rb_enc_from_index(idx);
}
else {
if (idx != -2) { // ":enc"
// `unsupported_encoding` is not in header file.
rb_warn("Unsupported encoding %s ignored", estr);
}
ext_enc = NULL;
}
int_enc = NULL;
if (ptr) {
if (*ptr == '-' && *(ptr+1) == '\0') { // "enc:-"
/* Special case - "-" => no transcoding */
int_enc = (rb_encoding *)Qnil;
}
else { // "enc2:enc"
idx2 = rb_enc_find_index(ptr);
if (idx2 < 0) {
// `unsupported_encoding` is not in header file.
rb_warn("Unsupported encoding %s ignored", ptr);
}
else if (idx2 == idx) {
int_enc = (rb_encoding *)Qnil;
}
else {
int_enc = rb_enc_from_index(idx2);
}
}
}
rb_io_ext_int_to_encs(ext_enc, int_enc, &enc, &enc2, 0);
}
else if (!NIL_P(option)) {
rb_raise(rb_eArgError, ":encoding has to be a String");
}
// @see CSV#raw_encoding
// @see https://github.com/ruby/ruby/blob/ab337e61ecb5f42384ba7d710c36faf96a454e5c/lib/csv.rb#L2290
if (rb_respond_to(port, rb_intern("internal_encoding"))) {
r_encoding = rb_funcall(port, rb_intern("internal_encoding"), 0);
if (NIL_P(r_encoding)) {
r_encoding = rb_funcall(port, rb_intern("external_encoding"), 0);
}
}
else if (rb_respond_to(port, rb_intern("string"))) {
r_encoding = rb_funcall(rb_funcall(port, rb_intern("string"), 0), rb_intern("encoding"), 0);
}
else if (rb_respond_to(port, rb_intern("encoding"))) {
r_encoding = rb_funcall(port, rb_intern("encoding"), 0);
}
else {
r_encoding = rb_enc_from_encoding(rb_ascii8bit_encoding());
}
// @see CSV#initialize
// @see https://github.com/ruby/ruby/blob/ab337e61ecb5f42384ba7d710c36faf96a454e5c/lib/csv.rb#L1510
if (NIL_P(r_encoding)) {
r_encoding = rb_enc_from_encoding(rb_default_internal_encoding());
}
if (NIL_P(r_encoding)) {
r_encoding = rb_enc_from_encoding(rb_default_external_encoding());
}
if (enc2 != NULL) {
encoding = enc2;
}
else if (enc != NULL) {
encoding = enc;
}
else if (!NIL_P(r_encoding)) {
encoding = rb_enc_get(r_encoding);
}
// In case #raw_parse is called multiple times on the same parser. Note that
// using IO methods on a re-used parser can cause segmentation faults.
rb_ivar_set(self, s_row, Qnil);
buffer_size = BUFSIZE;
if (rb_ivar_defined(self, rb_intern("@buffer_size")) == Qtrue) {
bufsize = rb_ivar_get(self, rb_intern("@buffer_size"));
if (!NIL_P(bufsize)) {
buffer_size = NUM2INT(bufsize);
// buffer_size = 0 can cause segmentation faults.
if (buffer_size == 0) {
buffer_size = BUFSIZE;
}
}
}
if (io) {
buf = ALLOC_N(char, buffer_size);
}
%% write init;
while (!done) {
VALUE str;
char *p, *pe;
int len, space = buffer_size - have, tokstart_diff, tokend_diff, start_diff, mark_row_sep_diff;
if (io) {
if (space == 0) {
// Not moving d->start will cause intermittent segmentation faults.
tokstart_diff = ts - buf;
tokend_diff = te - buf;
start_diff = d->start - buf;
mark_row_sep_diff = mark_row_sep - buf;
buffer_size += BUFSIZE;
REALLOC_N(buf, char, buffer_size);
space = buffer_size - have;
ts = buf + tokstart_diff;
te = buf + tokend_diff;
d->start = buf + start_diff;
mark_row_sep = buf + mark_row_sep_diff;
}
p = buf + have;
// Reads "`length` bytes without any conversion (binary mode)."
// "The resulted string is always ASCII-8BIT encoding."
// @see http://www.ruby-doc.org/core-2.1.4/IO.html#method-i-read
str = rb_funcall(port, s_read, 1, INT2FIX(space));
if (NIL_P(str)) {
// "`nil` means it met EOF at beginning," e.g. for `StringIO.new("")`.
len = 0;
}
else {
len = RSTRING_LEN(str);
memcpy(p, StringValuePtr(str), len);
}
// "The 1 to `length`-1 bytes string means it met EOF after reading the result."
if (len < space) {
// EOF actions don't work in scanners, so we add a sentinel value.
// @see http://www.complang.org/pipermail/ragel-users/2007-May/001516.html
// @see https://github.com/leeonix/lua-csv-ragel/blob/master/src/csv.rl
p[len++] = 0;
done = 1;
}
}
else {
p = RSTRING_PTR(port);
len = RSTRING_LEN(port);
p[len++] = 0;
done = 1;
}
if (d->start == 0) {
d->start = p;
}
pe = p + len;
%% write exec;
if (done && cs < raw_parse_first_final) {
if (d->start == 0 || p == d->start) { // same as new_row
rb_ivar_set(self, s_row, rb_str_new2(""));
}
else if (p > d->start) {
rb_ivar_set(self, s_row, rb_str_new(d->start, p - d->start));
}
FREE;
if (unclosed_line) {
rb_raise(eError, "Unclosed quoted field on line %d.", unclosed_line);
}
else {
rb_raise(eError, "Illegal quoting in line %d.", curline);
}
}
if (ts == 0) {
have = 0;
}
else if (io) {
have = pe - ts;
memmove(buf, ts, have);
// @see https://github.com/hpricot/hpricot/blob/master/ext/hpricot_scan/hpricot_scan.rl#L92
if (d->start > ts) {
d->start = buf + (d->start - ts);
}
if (mark_row_sep >= ts) {
mark_row_sep = buf + (mark_row_sep - ts);
}
te = buf + (te - ts);
ts = buf;
}
}
FREE;
return Qnil;
}
// @see https://github.com/ruby/ruby/blob/trunk/README.EXT#L616
static VALUE allocate(VALUE class) {
// @see https://github.com/nofxx/georuby_c/blob/b3b91fd90980d7c295ac8f6012d89878ea7cd569/ext/line.c#L66
Data *d = ALLOC(Data);
d->start = 0;
// @see https://github.com/nofxx/georuby_c/blob/b3b91fd90980d7c295ac8f6012d89878ea7cd569/ext/point.h#L26
// rb_gc_mark(d->start) or rb_gc_mark(d) cause warning "passing argument 1 of ‘rb_gc_mark’ makes integer from pointer without a cast"
// free(d->start) causes error "pointer being freed was not allocated"
return Data_Wrap_Struct(class, NULL, free, d);
}
// @see http://tenderlovemaking.com/2009/12/18/writing-ruby-c-extensions-part-1.html
// @see http://tenderlovemaking.com/2010/12/11/writing-ruby-c-extensions-part-2.html
void Init_fastcsv() {
s_read = rb_intern("read");
s_row = rb_intern("@row");
cClass = rb_define_class("FastCSV", rb_const_get(rb_cObject, rb_intern("CSV"))); // class FastCSV < CSV
cParser = rb_define_class_under(cClass, "Parser", rb_cObject); // class Parser
rb_define_alloc_func(cParser, allocate); //
rb_define_method(cParser, "raw_parse", raw_parse, -1); // def raw_parse(port, opts = nil); end
rb_define_attr(cParser, "row", 1, 0); // attr_reader :row
rb_define_attr(cParser, "buffer_size", 1, 1); // attr_accessor :buffer_size
// end
eError = rb_define_class_under(cClass, "MalformedCSVError", rb_eRuntimeError); // class MalformedCSVError < RuntimeError
// end
}