#
#
# Nimrod's Runtime Library
# (c) Copyright 2011 Andreas Rumpf
#
# See the file "copying.txt", included in this
# distribution, for details about the copyright.
#
## Converts between different character encodings. On UNIX, this uses
## the `iconv`:idx: library, on Windows the Windows API.
import os, parseutils, strutils
when not defined(windows):
type
TConverter = object {.pure, final.}
PConverter* = ptr TConverter ## can convert between two character sets
else:
type
TCodePage = distinct int32
PConverter* = object {.pure.}
dest, src: TCodePage
type
EInvalidEncoding* = object of EInvalidValue ## exception that is raised
## for encoding errors
when defined(windows):
proc EqEncodingNames(a, b: string): bool =
var i = 0
var j = 0
while i < a.len and j < b.len:
if a[i] in {'-', '_'}: inc i
if b[j] in {'-', '_'}: inc j
if a[i].tolower != b[j].tolower: return false
inc i
inc j
result = i == a.len and j == b.len
const
winEncodings = [
(037, "IBM037"), # IBM EBCDIC US-Canada
(437, "IBM437"), # OEM United States
(500, "IBM500"), # IBM EBCDIC International
(708, "ASMO-708"), # Arabic (ASMO 708)
(709, "ASMO_449"), # Arabic (ASMO-449+, BCON V4)
(710, ""), # Arabic - Transparent Arabic
(720, "DOS-720"), # Arabic (Transparent ASMO); Arabic (DOS)
(737, "ibm737"), # OEM Greek (formerly 437G); Greek (DOS)
(775, "ibm775"), # OEM Baltic; Baltic (DOS)
(850, "ibm850"), # OEM Multilingual Latin 1; Western European (DOS)
(852, "ibm852"), # OEM Latin 2; Central European (DOS)
(855, "IBM855"), # OEM Cyrillic (primarily Russian)
(857, "ibm857"), # OEM Turkish; Turkish (DOS)
(858, "IBM00858"), # OEM Multilingual Latin 1 + Euro symbol
(860, "IBM860"), # OEM Portuguese; Portuguese (DOS)
(861, "ibm861"), # OEM Icelandic; Icelandic (DOS)
(862, "DOS-862"), # OEM Hebrew; Hebrew (DOS)
(863, "IBM863"), # OEM French Canadian; French Canadian (DOS)
(864, "IBM864"), # OEM Arabic; Arabic (864)
(865, "IBM865"), # OEM Nordic; Nordic (DOS)
(866, "cp866"), # OEM Russian; Cyrillic (DOS)
(869, "ibm869"), # OEM Modern Greek; Greek, Modern (DOS)
(870, "IBM870"), # IBM EBCDIC Multilingual/ROECE (Latin 2); IBM EBCDIC Multilingual Latin 2
(874, "windows-874"), # ANSI/OEM Thai (same as 28605, ISO 8859-15); Thai (Windows)
(875, "cp875"), # IBM EBCDIC Greek Modern
(932, "shift_jis"), # ANSI/OEM Japanese; Japanese (Shift-JIS)
(936, "gb2312"), # ANSI/OEM Simplified Chinese (PRC, Singapore); Chinese Simplified (GB2312)
(949, "ks_c_5601-1987"), # ANSI/OEM Korean (Unified Hangul Code)
(950, "big5"), # ANSI/OEM Traditional Chinese (Taiwan; Hong Kong SAR, PRC); Chinese Traditional (Big5)
(1026, "IBM1026"), # IBM EBCDIC Turkish (Latin 5)
(1047, "IBM01047"), # IBM EBCDIC Latin 1/Open System
(1140, "IBM01140"), # IBM EBCDIC US-Canada (037 + Euro symbol); IBM EBCDIC (US-Canada-Euro)
(1141, "IBM01141"), # IBM EBCDIC Germany (20273 + Euro symbol); IBM EBCDIC (Germany-Euro)
(1142, "IBM01142"), # IBM EBCDIC Denmark-Norway (20277 + Euro symbol); IBM EBCDIC (Denmark-Norway-Euro)
(1143, "IBM01143"), # IBM EBCDIC Finland-Sweden (20278 + Euro symbol); IBM EBCDIC (Finland-Sweden-Euro)
(1144, "IBM01144"), # IBM EBCDIC Italy (20280 + Euro symbol); IBM EBCDIC (Italy-Euro)
(1145, "IBM01145"), # IBM EBCDIC Latin America-Spain (20284 + Euro symbol); IBM EBCDIC (Spain-Euro)
(1146, "IBM01146"), # IBM EBCDIC United Kingdom (20285 + Euro symbol); IBM EBCDIC (UK-Euro)
(1147, "IBM01147"), # IBM EBCDIC France (20297 + Euro symbol); IBM EBCDIC (France-Euro)
(1148, "IBM01148"), # IBM EBCDIC International (500 + Euro symbol); IBM EBCDIC (International-Euro)
(1149, "IBM01149"), # IBM EBCDIC Icelandic (20871 + Euro symbol); IBM EBCDIC (Icelandic-Euro)
(1200, "utf-16"), # Unicode UTF-16, little endian byte order (BMP of ISO 10646); available only to managed applications
(1201, "unicodeFFFE"), # Unicode UTF-16, big endian byte order; available only to managed applications
(1250, "windows-1250"), # ANSI Central European; Central European (Windows)
(1251, "windows-1251"), # ANSI Cyrillic; Cyrillic (Windows)
(1252, "windows-1252"), # ANSI Latin 1; Western European (Windows)
(1253, "windows-1253"), # ANSI Greek; Greek (Windows)
(1254, "windows-1254"), # ANSI Turkish; Turkish (Windows)
(1255, "windows-1255"), # ANSI Hebrew; Hebrew (Windows)
(1256, "windows-1256"), # ANSI Arabic; Arabic (Windows)
(1257, "windows-1257"), # ANSI Baltic; Baltic (Windows)
(1258, "windows-1258"), # ANSI/OEM Vietnamese; Vietnamese (Windows)
(1250, "cp-1250"), # ANSI Central European; Central European (Windows)
(1251, "cp-1251"), # ANSI Cyrillic; Cyrillic (Windows)
(1252, "cp-1252"), # ANSI Latin 1; Western European (Windows)
(1253, "cp-1253"), # ANSI Greek; Greek (Windows)
(1254, "cp-1254"), # ANSI Turkish; Turkish (Windows)
(1255, "cp-1255"), # ANSI Hebrew; Hebrew (Windows)
(1256, "cp-1256"), # ANSI Arabic; Arabic (Windows)
(1257, "cp-1257"), # ANSI Baltic; Baltic (Windows)
(1258, "cp-1258"), # ANSI/OEM Vietnamese; Vietnamese (Windows)
(1361, "Johab"), # Korean (Johab)
(10000, "macintosh"), # MAC Roman; Western European (Mac)
(10001, "x-mac-japanese"), # Japanese (Mac)
(10002, "x-mac-chinesetrad"), # MAC Traditional Chinese (Big5); Chinese Traditional (Mac)
(10003, "x-mac-korean"), # Korean (Mac)
(10004, "x-mac-arabic"), # Arabic (Mac)
(10005, "x-mac-hebrew"), # Hebrew (Mac)
(10006, "x-mac-greek"), # Greek (Mac)
(10007, "x-mac-cyrillic"), # Cyrillic (Mac)
(10008, "x-mac-chinesesimp"), # MAC Simplified Chinese (GB 2312); Chinese Simplified (Mac)
(10010, "x-mac-romanian"), # Romanian (Mac)
(10017, "x-mac-ukrainian"), # Ukrainian (Mac)
(10021, "x-mac-thai"), # Thai (Mac)
(10029, "x-mac-ce"), # MAC Latin 2; Central European (Mac)
(10079, "x-mac-icelandic"), # Icelandic (Mac)
(10081, "x-mac-turkish"), # Turkish (Mac)
(10082, "x-mac-croatian"), # Croatian (Mac)
(12000, "utf-32"), # Unicode UTF-32, little endian byte order; available only to managed applications
(12001, "utf-32BE"), # Unicode UTF-32, big endian byte order; available only to managed applications
(20000, "x-Chinese_CNS"), # CNS Taiwan; Chinese Traditional (CNS)
(20001, "x-cp20001"), # TCA Taiwan
(20002, "x_Chinese-Eten"), # Eten Taiwan; Chinese Traditional (Eten)
(20003, "x-cp20003"), # IBM5550 Taiwan
(20004, "x-cp20004"), # TeleText Taiwan
(20005, "x-cp20005"), # Wang Taiwan
(20105, "x-IA5"), # IA5 (IRV International Alphabet No. 5, 7-bit); Western European (IA5)
(20106, "x-IA5-German"), # IA5 German (7-bit)
(20107, "x-IA5-Swedish"), # IA5 Swedish (7-bit)
(20108, "x-IA5-Norwegian"), # IA5 Norwegian (7-bit)
(20127, "us-ascii"), # US-ASCII (7-bit)
(20261, "x-cp20261"), # T.61
(20269, "x-cp20269"), # ISO 6937 Non-Spacing Accent
(20273, "IBM273"), # IBM EBCDIC Germany
(20277, "IBM277"), # IBM EBCDIC Denmark-Norway
(20278, "IBM278"), # IBM EBCDIC Finland-Sweden
(20280, "IBM280"), # IBM EBCDIC Italy
(20284, "IBM284"), # IBM EBCDIC Latin America-Spain
(20285, "IBM285"), # IBM EBCDIC United Kingdom
(20290, "IBM290"), # IBM EBCDIC Japanese Katakana Extended
(20297, "IBM297"), # IBM EBCDIC France
(20420, "IBM420"), # IBM EBCDIC Arabic
(20423, "IBM423"), # IBM EBCDIC Greek
(20424, "IBM424"), # IBM EBCDIC Hebrew
(20833, "x-EBCDIC-KoreanExtended"), # IBM EBCDIC Korean Extended
(20838, "IBM-Thai"), # IBM EBCDIC Thai
(20866, "koi8-r"), # Russian (KOI8-R); Cyrillic (KOI8-R)
(20871, "IBM871"), # IBM EBCDIC Icelandic
(20880, "IBM880"), # IBM EBCDIC Cyrillic Russian
(20905, "IBM905"), # IBM EBCDIC Turkish
(20924, "IBM00924"), # IBM EBCDIC Latin 1/Open System (1047 + Euro symbol)
(20932, "EUC-JP"), # Japanese (JIS 0208-1990 and 0121-1990)
(20936, "x-cp20936"), # Simplified Chinese (GB2312); Chinese Simplified (GB2312-80)
(20949, "x-cp20949"), # Korean Wansung
(21025, "cp1025"), # IBM EBCDIC Cyrillic Serbian-Bulgarian
(21027, ""), # (deprecated)
(21866, "koi8-u"), # Ukrainian (KOI8-U); Cyrillic (KOI8-U)
(28591, "iso-8859-1"), # ISO 8859-1 Latin 1; Western European (ISO)
(28592, "iso-8859-2"), # ISO 8859-2 Central European; Central European (ISO)
(28593, "iso-8859-3"), # ISO 8859-3 Latin 3
(28594, "iso-8859-4"), # ISO 8859-4 Baltic
(28595, "iso-8859-5"), # ISO 8859-5 Cyrillic
(28596, "iso-8859-6"), # ISO 8859-6 Arabic
(28597, "iso-8859-7"), # ISO 8859-7 Greek
(28598, "iso-8859-8"), # ISO 8859-8 Hebrew; Hebrew (ISO-Visual)
(28599, "iso-8859-9"), # ISO 8859-9 Turkish
(28603, "iso-8859-13"), # ISO 8859-13 Estonian
(28605, "iso-8859-15"), # ISO 8859-15 Latin 9
(29001, "x-Europa"), # Europa 3
(38598, "iso-8859-8-i"), # ISO 8859-8 Hebrew; Hebrew (ISO-Logical)
(50220, "iso-2022-jp"), # ISO 2022 Japanese with no halfwidth Katakana; Japanese (JIS)
(50221, "csISO2022JP"), # ISO 2022 Japanese with halfwidth Katakana; Japanese (JIS-Allow 1 byte Kana)
(50222, "iso-2022-jp"), # ISO 2022 Japanese JIS X 0201-1989; Japanese (JIS-Allow 1 byte Kana - SO/SI)
(50225, "iso-2022-kr"), # ISO 2022 Korean
(50227, "x-cp50227"), # ISO 2022 Simplified Chinese; Chinese Simplified (ISO 2022)
(50229, ""), # ISO 2022 Traditional Chinese
(50930, ""), # EBCDIC Japanese (Katakana) Extended
(50931, ""), # EBCDIC US-Canada and Japanese
(50933, ""), # EBCDIC Korean Extended and Korean
(50935, ""), # EBCDIC Simplified Chinese Extended and Simplified Chinese
(50936, ""), # EBCDIC Simplified Chinese
(50937, ""), # EBCDIC US-Canada and Traditional Chinese
(50939, ""), # EBCDIC Japanese (Latin) Extended and Japanese
(51932, "euc-jp"), # EUC Japanese
(51936, "EUC-CN"), # EUC Simplified Chinese; Chinese Simplified (EUC)
(51949, "euc-kr"), # EUC Korean
(51950, ""), # EUC Traditional Chinese
(52936, "hz-gb-2312"), # HZ-GB2312 Simplified Chinese; Chinese Simplified (HZ)
(54936, "GB18030"), # Windows XP and later: GB18030 Simplified Chinese (4 byte); Chinese Simplified (GB18030)
(57002, "x-iscii-de"), # ISCII Devanagari
(57003, "x-iscii-be"), # ISCII Bengali
(57004, "x-iscii-ta"), # ISCII Tamil
(57005, "x-iscii-te"), # ISCII Telugu
(57006, "x-iscii-as"), # ISCII Assamese
(57007, "x-iscii-or"), # ISCII Oriya
(57008, "x-iscii-ka"), # ISCII Kannada
(57009, "x-iscii-ma"), # ISCII Malayalam
(57010, "x-iscii-gu"), # ISCII Gujarati
(57011, "x-iscii-pa"), # ISCII Punjabi
(65000, "utf-7"), # Unicode (UTF-7)
(65001, "utf-8")] # Unicode (UTF-8)
when false:
# not needed yet:
type
TCpInfo = object {.pure.}
MaxCharSize: int32
DefaultChar: array[0..1, char]
LeadByte: array[0..12-1, char]
proc GetCPInfo(CodePage: TCodePage, lpCPInfo: var TCpInfo): int32 {.
stdcall, importc: "GetCPInfo", dynlib: "kernel32".}
proc nameToCodePage(name: string): TCodePage =
var nameAsInt: int
if parseInt(name, nameAsInt) == 0: nameAsInt = -1
for no, na in items(winEncodings):
if no == nameAsInt or EqEncodingNames(na, name): return TCodePage(no)
result = TCodePage(-1)
proc codePageToName(c: TCodePage): string =
for no, na in items(winEncodings):
if no == int(c):
return if na.len != 0: na else: $no
result = ""
proc GetACP(): TCodePage {.stdcall, importc: "GetACP", dynlib: "kernel32".}
proc MultiByteToWideChar(
CodePage: TCodePage,
dwFlags: int32,
lpMultiByteStr: cstring,
cbMultiByte: cint,
lpWideCharStr: cstring,
cchWideChar: cint): cint {.
stdcall, importc: "MultiByteToWideChar", dynlib: "kernel32".}
proc WideCharToMultiByte(
CodePage: TCodePage,
dwFlags: int32,
lpWideCharStr: cstring,
cchWideChar: cint,
lpMultiByteStr: cstring,
cbMultiByte: cint,
lpDefaultChar: cstring=nil,
lpUsedDefaultChar: pointer=nil): cint {.
stdcall, importc: "WideCharToMultiByte", dynlib: "kernel32".}
else:
when defined(haiku):
const iconvDll = "(libc.so.6|libiconv.so|libtextencoding.so)"
else:
const iconvDll = "(libc.so.6|libiconv.so)"
when defined(macosx) and defined(powerpc32):
const prefix = "lib"
else:
const prefix = ""
const
E2BIG = 7.cint
EINVAL = 22.cint
when defined(linux):
const EILSEQ = 84.cint
elif defined(macosx):
const EILSEQ = 92.cint
elif defined(bsd):
const EILSEQ = 86.cint
elif defined(solaris):
const EILSEQ = 88.cint
var errno {.importc, header: "<errno.h>".}: cint
proc iconvOpen(tocode, fromcode: cstring): PConverter {.
importc: prefix & "iconv_open", cdecl, dynlib: iconvDll.}
proc iconvClose(c: PConverter) {.
importc: prefix & "iconv_close", cdecl, dynlib: iconvDll.}
proc iconv(c: PConverter, inbuf: var cstring, inbytesLeft: var int,
outbuf: var cstring, outbytesLeft: var int): int {.
importc: prefix & "iconv", cdecl, dynlib: iconvDll.}
proc iconv(c: PConverter, inbuf: pointer, inbytesLeft: pointer,
outbuf: var cstring, outbytesLeft: var int): int {.
importc: prefix & "iconv", cdecl, dynlib: iconvDll.}
proc getCurrentEncoding*(): string =
## retrieves the current encoding. On Unix, always "UTF-8" is returned.
when defined(windows):
result = codePageToName(GetACP())
else:
result = "UTF-8"
proc open*(destEncoding = "UTF-8", srcEncoding = "CP1252"): PConverter =
## opens a converter that can convert from `srcEncoding` to `destEncoding`.
## Raises `EIO` if it cannot fullfill the request.
when not defined(windows):
result = iconvOpen(srcEncoding, destEncoding)
if result == nil:
raise newException(EInvalidEncoding,
"cannot create encoding converter from " &
srcEncoding & " to " & destEncoding)
else:
result.dest = nameToCodePage(destEncoding)
result.src = nameToCodePage(srcEncoding)
if int(result.dest) == -1:
raise newException(EInvalidEncoding,
"cannot find encoding " & destEncoding)
if int(result.src) == -1:
raise newException(EInvalidEncoding,
"cannot find encoding " & srcEncoding)
proc close*(c: PConverter) =
## frees the resources the converter `c` holds.
when not defined(windows):
iconvClose(c)
when defined(windows):
proc convert*(c: PConverter, s: string): string =
## converts `s` to `destEncoding` that was given to the converter `c`. It
## assumed that `s` is in `srcEncoding`.
# special case: empty string: needed because MultiByteToWideChar
# return 0 in case of error:
if s.len == 0: return ""
# educated guess of capacity:
var cap = s.len + s.len shr 2
result = newStringOfCap(cap*2)
# convert to utf-16 LE
var m = MultiByteToWideChar(CodePage = c.src, dwFlags = 0'i32,
lpMultiByteStr = cstring(s),
cbMultiByte = cint(s.len),
lpWideCharStr = cstring(result),
cchWideChar = cint(cap))
if m == 0:
# try again; ask for capacity:
cap = MultiByteToWideChar(CodePage = c.src, dwFlags = 0'i32,
lpMultiByteStr = cstring(s),
cbMultiByte = cint(s.len),
lpWideCharStr = nil,
cchWideChar = cint(0))
# and do the conversion properly:
result = newStringOfCap(cap*2)
m = MultiByteToWideChar(CodePage = c.src, dwFlags = 0'i32,
lpMultiByteStr = cstring(s),
cbMultiByte = cint(s.len),
lpWideCharStr = cstring(result),
cchWideChar = cint(cap))
if m == 0: OSError()
setLen(result, m*2)
elif m <= cap:
setLen(result, m*2)
else:
assert(false) # cannot happen
# if already utf-16 LE, no further need to do something:
if int(c.dest) == 1200: return
# otherwise the fun starts again:
cap = s.len + s.len shr 2
var res = newStringOfCap(cap)
m = WideCharToMultiByte(
CodePage = c.dest,
dwFlags = 0'i32,
lpWideCharStr = cstring(result),
cchWideChar = cint(result.len div 2),
lpMultiByteStr = cstring(res),
cbMultiByte = cap)
if m == 0:
# try again; ask for capacity:
cap = WideCharToMultiByte(
CodePage = c.dest,
dwFlags = 0'i32,
lpWideCharStr = cstring(result),
cchWideChar = cint(result.len div 2),
lpMultiByteStr = nil,
cbMultiByte = cint(0))
# and do the conversion properly:
res = newStringOfCap(cap)
m = WideCharToMultiByte(
CodePage = c.dest,
dwFlags = 0'i32,
lpWideCharStr = cstring(result),
cchWideChar = cint(result.len div 2),
lpMultiByteStr = cstring(res),
cbMultiByte = cap)
if m == 0: OSError()
setLen(res, m)
result = res
elif m <= cap:
setLen(res, m)
result = res
else:
assert(false) # cannot happen
else:
proc convert*(c: PConverter, s: string): string =
result = newString(s.len)
var inLen = len(S)
var outLen = len(result)
var src = cstring(S)
var dst = cstring(result)
var iconvres: int
while InLen > 0:
iconvres = iconv(c, src, inLen, dst, outLen)
if iconvres == -1:
var lerr = errno
if lerr == EILSEQ or lerr == EINVAL:
# unknown char, skip
Dst[0] = Src[0]
src = cast[cstring](cast[int](src) + 1)
dst = cast[cstring](cast[int](dst) + 1)
dec(inLen)
dec(outLen)
elif lerr == E2BIG:
var offset = cast[int](dst) - cast[int](cstring(result))
setLen(result, len(result)+inLen*2+5)
# 5 is minimally one utf-8 char
dst = cast[cstring](cast[int](cstring(result)) + offset)
outLen = len(result) - offset
else:
OSError()
# iconv has a buffer that needs flushing, specially if the last char is
# not '\0'
discard iconv(c, nil, nil, dst, outlen)
if iconvres == Cint(-1) and errno == E2BIG:
var offset = cast[int](dst) - cast[int](cstring(result))
setLen(result, len(result)+inLen*2+5)
# 5 is minimally one utf-8 char
dst = cast[cstring](cast[int](cstring(result)) + offset)
outLen = len(result) - offset
discard iconv(c, nil, nil, dst, outlen)
# trim output buffer
setLen(result, len(result) - outlen)
proc convert*(s: string, destEncoding = "UTF-8",
srcEncoding = "CP1252"): string =
## converts `s` to `destEncoding`. It assumed that `s` is in `srcEncoding`.
## This opens a converter, uses it and closes it again and is thus more
## convienent but also likely less efficient than re-using a converter.
var c = open(destEncoding, srcEncoding)
try:
result = convert(c, s)
finally:
close(c)
when IsMainModule:
var orig = "öäüß"
var crap = convert(orig, "CP1252", "UTF-8")
echo convert(crap, "ibm850", "CP1252")
echo getCurrentEncoding()