Fix mappings between LCIDs and code pages. (#169)

* Fix mappings between LCIDs and code pages.

* Add test for fetching various LCIDs.

* Address Github automation feedback.

* Refine comments.

---------

Co-authored-by: Sergey Ten <[email protected]>

internal/cp/charset.go

@@ -60,31 +60,31 @@ func collation2charset(col Collation) *charsetMap {
 	switch col.getLcid() {
 	case 0x001e, 0x041e:
 		return cp874
-	case 0x0411, 0x10411:
+	case 0x0411, 0x10411, 0x40411:
 		return cp932
 	case 0x0804, 0x1004, 0x20804:
 		return cp936
 	case 0x0012, 0x0412:
 		return cp949
-	case 0x0404, 0x1404, 0x0c04, 0x7c04, 0x30404:
+	case 0x0404, 0x1404, 0x0c04, 0x7c04, 0x30404, 0x21404:
 		return cp950
-	case 0x041c, 0x041a, 0x0405, 0x040e, 0x104e, 0x0415, 0x0418, 0x041b, 0x0424, 0x1040e:
+	case 0x041c, 0x041a, 0x0405, 0x040e, 0x104e, 0x0415, 0x0418, 0x041b, 0x0424, 0x1040e, 0x0442, 0x081A, 0x141A:
 		return cp1250
-	case 0x0423, 0x0402, 0x042f, 0x0419, 0x081a, 0x0c1a, 0x0422, 0x043f, 0x0444, 0x082c:
+	case 0x0423, 0x0402, 0x042f, 0x0419, 0x0c1a, 0x0422, 0x043f, 0x0444, 0x082c, 0x046D, 0x0485, 0x201A:
 		return cp1251
 	case 0x0408:
 		return cp1253
 	case 0x041f, 0x042c, 0x0443:
 		return cp1254
 	case 0x040d:
 		return cp1255
-	case 0x0401, 0x0801, 0xc01, 0x1001, 0x1401, 0x1801, 0x1c01, 0x2001, 0x2401, 0x2801, 0x2c01, 0x3001, 0x3401, 0x3801, 0x3c01, 0x4001, 0x0429, 0x0420:
+	case 0x0401, 0x0801, 0xc01, 0x1001, 0x1401, 0x1801, 0x1c01, 0x2001, 0x2401, 0x2801, 0x2c01, 0x3001, 0x3401, 0x3801, 0x3c01, 0x4001, 0x0429, 0x0420, 0x0480, 0x048C:
 		return cp1256
 	case 0x0425, 0x0426, 0x0427, 0x0827:
 		return cp1257
 	case 0x042a:
 		return cp1258
-	case 0x0439, 0x045a, 0x0465:
+	case 0x0439, 0x045a, 0x0465, 0x043A, 0x0445, 0x044D, 0x0451, 0x0453, 0x0454, 0x0461, 0x0463, 0x0481:
 		return nil
 	}
 	return cp1252

lcids_test.go

@@ -0,0 +1,345 @@
+package mssql
+
+import (
+	"bytes"
+	"database/sql"
+	"encoding/binary"
+	"testing"
+)
+
+// SQL that generates other SQLs for running comparisons.
+// It does not create any persisent database objects,
+// employing CTEs instead. The structure of CTEs is pretty
+// self-explanatory, with one CTE per code page containing
+// all available LCIDs. The exception is code page 1252, which
+// contains all LCIDs not included in all other CTEs.
+//
+// There are some test integrity assertions that:
+//  1. Ensure that all LCIDs in the system (as returned by sys.fn_helpcollations())
+//     are covered by the test.
+//  2. The 1252 CTE does not return any "leaked" code pages that are not 1252.
+//  3. All code pages come with sample reference data for fetching comparison.
+//
+// None of the SQL syntax uses any SQL Server version-specific syntax,
+// and should work on any version without change.
+const comparisonQueriesGeneratorSQL = `
+--
+-- Generates SELECT statements for fetching data encoded with various code pages
+-- along with the same data encoded in UTF-16.
+-- The client can execute the generated queries and compare "codepage_data" column
+-- with the original data returned in the "reference_data" column.
+--
+-- Single-byte code pages contain the entire range of 128-255 byte values as sample data.
+-- Double-byte code pages contain a representative sample text since it is not practical
+-- to provide the entire range of possible characters.
+--
+-- The format of the query is
+--    SELECT
+--        N'<sample data>' AS [reference_data]
+--      , CAST(N'<sample data> COLLATE <collation with the given code page and lcid> AS VARCHAR(1000)) AS [codepage_data]
+-- This way the conversion from Nvarchar to Varchar does not depend on the collation
+-- of the currently active database.
+--
+-- The dirver's job is to fetch both columns and compare them. If the codepage/LCID mapping is done wrong,
+-- the comparison will fail.
+--
+with
+cte_data (cp, datasample) as (
+  -- Thai
+  select  874, N'€…‘’“”•–—กขฃคฅฆงจฉชซฌฎฏฐฑฒณดตถทธนบปผฝพฟภมยรฤลฦวศษสหฬอฮฯะัาำิีึืฺุู฿เแโใไๅๆ็่้๊๋์ํ๎๏๐๑๒๓๔๕๖๗๘๙๚๛'
+  union all
+  -- Japanese (double-byte encoding, so provide a sample rather than the entire range)
+  select  932, N'産業通商資源部の安徳根（アン・ドクグン）長官は「今後もモバイル・ワールド・コングレス（ＭＷＣ）など海外の見本市で統合韓国館を拡大し、参加企業の成果を高める」との方針を示した。'
+  union all
+  -- Chinese Simplified (double-byte encoding, so provide a sample rather than the entire range)
+  select  936, N'乘坐“蓝梦之星”号邮轮访问济州的中国团体游客造访新罗免税店济州分店。'
+  union all
+  -- Chinese Traditional (double-byte encoding, so provide a sample rather than the entire range)
+  select  950, N'首相弗雷澤里克森在首相府和國會所在地克里斯蒂安堡宮的露台上，向民眾公布王儲正式登基成為國王。'
+  union all
+  -- Korean (double-byte encoding, so provide a sample rather than the entire range)
+  select  949, N'홍성은 마늘과 한돈, 김 등 산지로 유명하지만, 그동안 상대적으로 시설원예 분야에서는 취약하다는 평가를 받았다.'
+  union all
+  -- Central European (Czech, Slovak, Polish, Hungarian, etc.)
+  select 1250, N'€‚„…†‡‰Š‹ŚŤŽŹ‘’“”•–—™š›śťžźˇ˘Ł¤Ą¦§¨©Ş«¬®Ż°±˛ł´µ¶·¸ąş»Ľ˝ľżŔÁÂĂÄĹĆÇČÉĘËĚÍÎĎĐŃŇÓÔŐÖ×ŘŮÚŰÜÝŢßŕáâăäĺćçčéęëěíîďđńňóôőö÷řůúűüýţ˙'
+  union all
+  -- Cyrillic
+  select 1251, N'ЂЃ‚ѓ„…†‡€‰Љ‹ЊЌЋЏђ‘’“”•–—™љ›њќћџЎўЈ¤Ґ¦§Ё©Є«¬®Ї°±Ііґµ¶·ё№є»јЅѕїАБВГДЕЖЗИЙКЛМНОПРСТУФХЦЧШЩЪЫЬЭЮЯабвгдежзийклмнопрстуфхцчшщъыьэюя'
+  union all
+  -- Generic Latin
+  select 1252, N'€‚ƒ„…†‡ˆ‰Š‹ŒŽ‘’“”•–—˜™š›œžŸ¡¢£¤¥¦§¨©ª«¬®¯°±²³´µ¶·¸¹º»¼½¾¿ÀÁÂÃÄÅÆÇÈÉÊËÌÍÎÏÐÑÒÓÔÕÖ×ØÙÚÛÜÝÞßàáâãäåæçèéêëìíîïðñòóôõö÷øùúûüýþÿ'
+  union all
+  -- Greek
+  select 1253, N'€‚ƒ„…†‡‰‹‘’“”•–—™›΅Ά£¤¥¦§¨©«¬®―°±²³΄µ¶·ΈΉΊ»Ό½ΎΏCxΐΑΒΓΔΕΖΗΘΙΚΛΜΝΞΟΠΡΣΤΥΦΧΨΩΪΫάέήίΰαβγδεζηθικλμνξοπρςστυφχψωϊϋόύώ'
+  union all
+  -- Turkish
+  select 1254, N'€‚ƒ„…†‡ˆ‰Š‹Œ‘’“”•–—˜™š›œŸ¡¢£¤¥¦§¨©ª«¬®¯°±²³´µ¶·¸¹º»¼½¾¿ÀÁÂÃÄÅÆÇÈÉÊËÌÍÎÏĞÑÒÓÔÕÖ×ØÙÚÛÜİŞßàáâãäåæçèéêëìíîïğñòóôõö÷øùúûüışÿ'
+  union all
+  -- Hebrew
+  select 1255, N'€‚ƒ„…†‡ˆ‰‹‘’“”•–—˜™›¡¢£₪¥¦§¨©×«¬®¯°±²³´µ¶·¸¹÷»¼½¾¿ְֱֲֳִֵֶַָֻּֽ־ֿ׀ׁׂ׃װױײ׳״אבגדהוזחטיךכלםמןנסעףפץצקרשת'
+  union all
+  -- Arabic
+  select 1256, N'€پ‚ƒ„…†‡ˆ‰ٹ‹Œچژڈگ‘’“”•–—ک™ڑ›œں،¢£¤¥¦§¨©ھ«¬®¯°±²³´µ¶·¸¹؛»¼½¾؟ہءآأؤإئابةتثجحخدذرزسشصض×طظعغـفقكàلâمنهوçèéêëىيîô÷ùûüے'
+  union all
+  -- Baltic countries (Estonia, Latvia, Lithuania)
+  select 1257, N'€‚„…†‡‰‹¨ˇ¸‘’“”•–—™›¯˛¢£¤¦§Ø©Ŗ«¬®Æ°±²³´µ¶·ø¹ŗ»¼½¾æĄĮĀĆÄÅĘĒČÉŹĖĢĶĪĻŠŃŅÓŌÕÖ×ŲŁŚŪÜŻŽßąįāćäåęēčéźėģķīļšńņóōõö÷ųłśūüżž˙'
+  union all
+  -- Vietnamese
+  select 1258, N'€‚ƒ„…†‡ˆ‰‹Œ‘’“”•–—˜™›œŸ¡¢£¤¥¦§¨©ª«¬®¯°±²³´µ¶·¸¹º»¼½¾¿ÀÁÂĂÄÅÆÇÈÉÊËÍÎÏĐÑÓÔƠÖ×ØÙÚÛÜƯßàáâăäåæçèéêëíîïđñóôơö÷øùúûüư₫ÿ'
+),
+cte_cp874 (cp, lcid, collation) as (
+            select 874, 0x0000041e, N'Thai_100_BIN2'
+),
+cte_cp932 (cp, lcid, collation) as (
+            select 932, 0x00000411, N'Japanese_XJIS_100_BIN2'
+  union all select 932, 0x00010411, N'Japanese_Unicode_BIN2'
+  union all select 932, 0x00040411, N'Japanese_Bushu_Kakusu_100_BIN2'
+),
+cte_cp936 (cp, lcid, collation) as (
+            select 936, 0x00000804, N'Chinese_Simplified_Pinyin_100_BIN2'
+  union all select 936, 0x00020804, N'Chinese_Simplified_Stroke_Order_100_BIN2'
+),
+cte_cp949 (cp, lcid, collation) as (
+            select 949, 0x00000412, N'Korean_100_BIN2'
+),
+cte_cp950 (cp, lcid, collation) as (
+            select 950, 0x00000404, N'Chinese_Traditional_Stroke_Count_100_BIN2'
+  union all select 950, 0x00001404, N'Chinese_Traditional_Pinyin_100_BIN2'
+  union all select 950, 0x00000c04, N'Chinese_Hong_Kong_Stroke_90_BIN2'
+  union all select 950, 0x00030404, N'Chinese_Traditional_Bopomofo_100_BIN2'
+  union all select 950, 0x00021404, N'Chinese_Traditional_Stroke_Order_100_BIN2'
+),
+cte_cp1250 (cp, lcid, collation) as (
+            select 1250, 0x0000041c, N'Albanian_100_BIN2'
+  union all select 1250, 0x0000041a, N'Croatian_100_BIN2'
+  union all select 1250, 0x00000405, N'Czech_100_BIN2'
+  union all select 1250, 0x0000040e, N'Hungarian_100_BIN2'
+  union all select 1250, 0x00000415, N'Polish_100_BIN2'
+  union all select 1250, 0x00000418, N'Romanian_100_BIN2'
+  union all select 1250, 0x0000041b, N'Slovak_100_BIN2'
+  union all select 1250, 0x00000424, N'Slovenian_100_BIN2'
+  union all select 1250, 0x0001040e, N'Hungarian_Technical_100_BIN2'
+  union all select 1250, 0x00000442, N'Turkmen_100_BIN2'
+  union all select 1250, 0x0000081A, N'Serbian_Latin_100_BIN2'
+  union all select 1250, 0x0000141A, N'Bosnian_Latin_100_BIN2'
+),
+cte_cp1251 (cp, lcid, collation) as (
+            select 1251, 0x0000042f, N'Macedonian_FYROM_100_BIN2'
+  union all select 1251, 0x00000419, N'Cyrillic_General_100_BIN2'
+  union all select 1251, 0x00000c1a, N'Serbian_Cyrillic_100_BIN2'
+  union all select 1251, 0x00000422, N'Ukrainian_100_BIN2'
+  union all select 1251, 0x0000043f, N'Kazakh_100_BIN2'
+  union all select 1251, 0x00000444, N'Tatar_100_BIN2'
+  union all select 1251, 0x0000082c, N'Azeri_Cyrillic_100_BIN2'
+  union all select 1251, 0x0000046D, N'Bashkir_100_BIN2'
+  union all select 1251, 0x00000485, N'Yakut_100_BIN2'
+  union all select 1251, 0x0000201A, N'Bosnian_Cyrillic_100_BIN2'
+),
+cte_cp1253 (cp, lcid, collation) as (
+            select 1253, 0x00000408, N'Greek_100_BIN2'
+),
+cte_cp1254 (cp, lcid, collation) as (
+            select 1254, 0x0000041f, N'Turkish_100_BIN2'
+  union all select 1254, 0x0000042c, N'Azeri_Latin_100_BIN2'
+  union all select 1254, 0x00000443, N'Uzbek_Latin_100_BIN2'
+),
+cte_cp1255 (cp, lcid, collation) as (
+            select 1255, 0x0000040d, N'Hebrew_100_BIN2'
+),
+cte_cp1256 (cp, lcid, collation) as (
+            select 1256, 0x00000401, N'Arabic_100_BIN2'
+  union all select 1256, 0x00000429, N'Persian_100_BIN2'
+  union all select 1256, 0x00000420, N'Urdu_100_BIN2'
+  union all select 1256, 0x00000480, N'Uighur_100_BIN2'
+  union all select 1256, 0x0000048C, N'Dari_100_BIN2'
+),
+cte_cp1257 (cp, lcid, collation) as (
+            select 1257, 0x00000425, N'Estonian_100_BIN2'
+  union all select 1257, 0x00000426, N'Latvian_100_BIN2'
+  union all select 1257, 0x00000427, N'Lithuanian_100_BIN2'
+),
+cte_cp1258 (cp, lcid, collation) as (
+            select 1258, 0x0000042a, N'Vietnamese_100_BIN2'
+),
+cte_cp_non1252 (cp, lcid, collation) as (
+            select cp, lcid, collation from cte_cp874
+  union all select cp, lcid, collation from cte_cp932
+  union all select cp, lcid, collation from cte_cp936
+  union all select cp, lcid, collation from cte_cp949
+  union all select cp, lcid, collation from cte_cp950
+  union all select cp, lcid, collation from cte_cp1250
+  union all select cp, lcid, collation from cte_cp1251
+  union all select cp, lcid, collation from cte_cp1253
+  union all select cp, lcid, collation from cte_cp1254
+  union all select cp, lcid, collation from cte_cp1255
+  union all select cp, lcid, collation from cte_cp1256
+  union all select cp, lcid, collation from cte_cp1257
+  union all select cp, lcid, collation from cte_cp1258
+),
+cte_cp1252 (cp, lcid, collation) as (
+  select distinct
+      -- TEST INTEGRITY ASSERTION:
+      -- If there's any code page that is not 1252 - cause a failure.
+      -- Use "divide by zero" as a distinctive error for this failure point.
+      iif(collationproperty(name, 'codepage') = 1252, 1252, 1/0)
+    , cast(collationproperty(name, 'lcid') as binary(4))
+      -- Doesn't matter which collation to pick as long as it's the only one for the given codepage/lcid combo.
+    , max (name) over (partition by collationproperty(name, 'codepage'), collationproperty(name, 'lcid'))
+  from fn_helpcollations() hc
+  where
+      collationproperty(name, 'codepage') not in (0, 65001)
+  and collationproperty(name, 'sortid') = 0
+  and not exists (
+  select * from cte_cp_non1252
+  where
+        cp = collationproperty(hc.name, 'codepage')
+    and lcid = cast(collationproperty(hc.name, 'lcid') as binary(4)))
+),
+cte_cp_all (cp, lcid, collation) as (
+            select cp, lcid, collation from cte_cp_non1252
+  union all select cp, lcid, collation from cte_cp1252
+),
+cte_sqltext (cp, lcid, collation, sqltext) as (
+select
+    cte_cp_all.cp
+  , cte_cp_all.lcid
+  , cte_cp_all.collation
+  , N'select' + char(13) + char(10) +
+    N'  N''' + cte_data.datasample + N''' as reference_data' + nchar(13) + nchar(10) +
+    N', cast(N''' + cte_data.datasample + N''' collate ' + cte_cp_all.collation + N' as varchar(1000)) as codepage_data'
+from
+  cte_cp_all left join cte_data on (cte_cp_all.cp = cte_data.cp)
+)
+select cp, lcid, collation, sqltext from cte_sqltext
+union all
+select
+    -- TEST INTEGRITY ASSERTION:
+    -- Check if all codepages have a sample data associated with them.
+    -- The "sqltext" property will be set to NULL for those that do not.
+    -- Cause a failure if found.
+    -- Use "arithmetic overflow" as a distinctive error for this failure point
+    -- by casting the code page value (that is greater than 255) to tinyint.
+    cast(cp as tinyint), null, null, null
+from cte_sqltext
+where sqltext is null
+union all
+select
+    -- TEST INTEGRITY ASSERTION:
+    -- Check for "orphan" codepage/lcid combos that are present in SQL server
+    -- but not covered by the above CTEs. Exclude:
+    --   - SQL collations (the ones whose SortId is nonzero)
+    --   - Unicode-only collations (the ones that do not have a code page)
+    --   - UTF-8 collations - those are orthogonal to LCIDs and don't need to be tested.
+    -- If found such orphan combos - cause a failure.
+    -- Use "invalid cast" as a distinctive error for this failure point by
+    -- casting collation name (that is guaranteed to not be a valid number) to a number.
+    cast(name as int), null, null, null
+from fn_helpcollations() hc
+where
+      collationproperty(name, 'codepage') not in (0, 65001)
+  and collationproperty(name, 'sortid') = 0
+  and not exists (
+    select * from cte_cp_all where
+        cast(collationproperty(hc.name, 'lcid') as binary(4)) = cte_cp_all.lcid
+    and collationproperty(hc.name, 'codepage') = cte_cp_all.cp
+  )
+`
+
+// Represents codepage/LCID pair
+type CpLcid struct {
+	cp   int
+	lcid int32
+}
+
+// Represents a collation / comparison SQL text data
+// for each given codepage/LCID pair.
+type CpLcidComparisonData struct {
+	collation string
+	sqltext   string
+}
+
+// Type alias for the mapping of codepage/LCID pair
+// to its collation/sqltext data.
+type CpLcidComparisonMap map[CpLcid]CpLcidComparisonData
+
+// Builds a map of LCID fetching queries for all codepage/LCID pairs.
+func buildLcidFetchComparisonMap(conn *sql.DB, t *testing.T) CpLcidComparisonMap {
+	stmt, err := conn.Prepare(comparisonQueriesGeneratorSQL)
+	if err != nil {
+		t.Error("Unable to run comparison queries generator query", err.Error())
+	}
+	defer stmt.Close()
+
+	rows, err := stmt.Query()
+	if err != nil {
+		t.Error("Query failed:", err.Error())
+	}
+	defer rows.Close()
+
+	result := make(CpLcidComparisonMap)
+
+	for rows.Next() {
+		var codepage int
+		var lcidRaw []byte = make([]byte, 4)
+		var collation string
+		var sqltext string
+
+		err := rows.Scan(&codepage, &lcidRaw, &collation, &sqltext)
+		if err != nil {
+			t.Error("Failed to fetch the comparison SQL text row:", err.Error())
+		}
+
+		var lcid int32
+		err = binary.Read(bytes.NewReader(lcidRaw), binary.BigEndian, &lcid)
+		if err != nil {
+			t.Error("Failed to convert LCID from binary to int:", err.Error())
+		}
+
+		cplcid := CpLcid{codepage, lcid}
+		cplciddata := CpLcidComparisonData{collation, sqltext}
+
+		result[cplcid] = cplciddata
+	}
+
+	err = rows.Err()
+	if err != nil {
+		t.Error("Rows containing comparison queries have errors", err)
+	}
+
+	return result
+}
+
+// Verifies a specific LCID fetch by comparing it to its reference data.
+func verifyLcidFetch(conn *sql.DB, sqltext *string, t *testing.T) bool {
+	var refdata string
+	var cpdata string
+
+	err := conn.QueryRow(*sqltext).Scan(&refdata, &cpdata)
+	if err != nil {
+		t.Error("Cannot scan reference and codepage data", err)
+	}
+
+	return refdata == cpdata
+}
+
+// Tests the fetching of all available LCIDs to verify that they
+// are being correctly mapped to their respective Windows code pages.
+func TestLcidsFetching(t *testing.T) {
+	conn, _ := sql.Open("sqlserver", makeConnStr(t).String())
+	defer conn.Close()
+
+	cplcidmap := buildLcidFetchComparisonMap(conn, t)
+
+	success := true
+	for cplcid, cplciddata := range cplcidmap {
+		if !verifyLcidFetch(conn, &cplciddata.sqltext, t) {
+			success = false
+			t.Logf("LCID fetch failed for codepage %d, lcid 0x%x, collation %s",
+				cplcid.cp, cplcid.lcid, cplciddata.collation)
+		}
+	}
+
+	if !success {
+		t.Error("There are failed LCID fetches. See test log for the details.")
+	}
+}