Suppressing UTFException / Squashing Bad Codepoints?

Dec 23, 2013

John Carter

Dec 23, 2013

Brad Anderson

Dec 23, 2013

John Carter

Dec 24, 2013

Brad Anderson

Dec 24, 2013

Jonathan M Davis

This frustrated me in Ruby unicode too.... Typically i/o is the ultimate in "untrusted and untrustworthy" sources, coming usually from systems beyond my control. Likely to be corrupted, or maliciously crafted, or defective... Unfortunately not all sequences of bytes are valid UTF8. Thus inevitably in every collection of inputs there are always going to be around 1 in a million codepoints resulting in an UTFException thrown. Alas, I always have to do Regex matches on the other 999999 valid codepoints..... Is there a standard recipe in stdio for squashing bad codepoints to some default? These days memory is very much larger than most files I want to scan. So if I was doing this in C I would typically mmap the file PROT_READ | PROT_WRITE and MAP_PRIVATE then run down the file squashing bad codepoints and then run down it again matching patterns. In Ruby I have a horridly inefficient utility.... def IO.read_utf_8(file) read(file,:external_encoding=>'ASCII-8BIT').encode('UTF-8',:undef=>:replace) end What is the idiomatic D solution to this conundrum? -- John Carter Phone : (64)(3) 358 6639 Tait Electronics PO Box 1645 Christchurch New Zealand -- ------------------------------ This email, including any attachments, is only for the intended recipient. It is subject to copyright, is confidential and may be the subject of legal or other privilege, none of which is waived or lost by reason of this transmission. If you are not an intended recipient, you may not use, disseminate, distribute or reproduce such email, any attachments, or any part thereof. If you have received a message in error, please notify the sender immediately and erase all copies of the message and any attachments. Unfortunately, we cannot warrant that the email has not been altered or corrupted during transmission nor can we guarantee that any email or any attachments are free from computer viruses or other conditions which may damage or interfere with recipient data, hardware or software. The recipient relies upon its own procedures and assumes all risk of use and of opening any attachments. ------------------------------

On Monday, 23 December 2013 at 20:48:08 UTC, John Carter wrote: > This frustrated me in Ruby unicode too.... > > Typically i/o is the ultimate in "untrusted and untrustworthy" sources, > coming usually from systems beyond my control. > > Likely to be corrupted, or maliciously crafted, or defective... > > Unfortunately not all sequences of bytes are valid UTF8. > > Thus inevitably in every collection of inputs there are always going to be > around 1 in a million codepoints resulting in an UTFException thrown. > > Alas, I always have to do Regex matches on the other 999999 valid > codepoints..... > > Is there a standard recipe in stdio for squashing bad codepoints to some > default? > > These days memory is very much larger than most files I want to scan. > > So if I was doing this in C I would typically mmap the file PROT_READ | > PROT_WRITE and MAP_PRIVATE then run down the file squashing bad codepoints > and then run down it again matching patterns. > > In Ruby I have a horridly inefficient utility.... > def IO.read_utf_8(file) > > read(file,:external_encoding=>'ASCII-8BIT').encode('UTF-8',:undef=>:replace) > end > > What is the idiomatic D solution to this conundrum? The encoding schemes in std.encoding support cleaning up input using the sanitize function. http://dlang.org/phobos/std_encoding.html#.EncodingScheme.sanitize It'd be nicer if the API were range based but it seems to do the trick in my experience.