From b55bb2a8b16be4144055c760b1422800c45fdbb6 Mon Sep 17 00:00:00 2001
From: maron2000 <68574602+maron2000@users.noreply.github.com>
Date: Sat, 5 Oct 2024 08:56:07 +0900
Subject: [PATCH 01/10] Add function to check codepage is DBCS

---
 src/dos/drive_local.cpp   |  8 ++++----
 src/ints/bios_disk.cpp    |  4 ++--
 src/misc/messages.cpp     | 16 +++++++++++++---
 src/output/output_ttf.cpp |  5 +++--
 src/shell/shell_cmds.cpp  |  5 +++--
 5 files changed, 25 insertions(+), 13 deletions(-)

diff --git a/src/dos/drive_local.cpp b/src/dos/drive_local.cpp
index 6308fe7b20..385a147654 100644
--- a/src/dos/drive_local.cpp
+++ b/src/dos/drive_local.cpp
@@ -111,7 +111,7 @@ std::string ldir[256];
 static host_cnv_char_t cpcnv_temp[4096];
 static host_cnv_char_t cpcnv_ltemp[4096];
 host_cnv_char_t *CodePageGuestToHost(const char *s);
-extern bool isDBCSCP(), isKanji1(uint8_t chr), shiftjis_lead_byte(int c);
+bool isDBCSCP(), isKanji1(uint8_t chr), shiftjis_lead_byte(int c), CheckDBCSCP(int32_t codepage);
 extern bool rsize, morelen, force_sfn, enable_share_exe, chinasea, uao, halfwidthkana, dbcs_sbcs, inmsg, forceswk;
 extern int lfn_filefind_handle, freesizecap, file_access_tries;
 extern unsigned long totalc, freec;
@@ -1010,7 +1010,7 @@ bool CodePageGuestToHostUTF8(char *d/*CROSS_LEN*/,const char *s/*CROSS_LEN*/) {
 host_cnv_char_t *CodePageGuestToHost(const char *s) {
 #if defined(host_cnv_use_wchar)
     uint16_t cp = GetACP(), cpbak = dos.loaded_codepage;
-    if (tryconvertcp && !notrycp && cpbak == 437 && (cp == 932 || cp == 936 || cp == 949 || cp == 950 || cp == 951)) {
+    if (tryconvertcp && !notrycp && cpbak == 437 && CheckDBCSCP(cp)) {
         dos.loaded_codepage = cp;
         if (CodePageGuestToHostUTF16((uint16_t *)cpcnv_temp,s)) {
             dos.loaded_codepage = cpbak;
@@ -1030,7 +1030,7 @@ host_cnv_char_t *CodePageGuestToHost(const char *s) {
 char *CodePageHostToGuest(const host_cnv_char_t *s) {
 #if defined(host_cnv_use_wchar)
     uint16_t cp = GetACP(), cpbak = dos.loaded_codepage;
-    if (tryconvertcp && !notrycp && cpbak == 437 && (cp == 932 || cp == 936 || cp == 949 || cp == 950 || cp == 951)) {
+    if (tryconvertcp && !notrycp && cpbak == 437 && CheckDBCSCP(cp)) {
         dos.loaded_codepage = cp;
         if (CodePageHostToGuestUTF16((char *)cpcnv_temp,(const uint16_t *)s)) {
             dos.loaded_codepage = cpbak;
@@ -1050,7 +1050,7 @@ char *CodePageHostToGuest(const host_cnv_char_t *s) {
 char *CodePageHostToGuestL(const host_cnv_char_t *s) {
 #if defined(host_cnv_use_wchar)
     uint16_t cp = GetACP(), cpbak = dos.loaded_codepage;
-    if (tryconvertcp && !notrycp && cpbak == 437 && (cp == 932 || cp == 936 || cp == 949 || cp == 950 || cp == 951)) {
+    if (tryconvertcp && !notrycp && cpbak == 437 && CheckDBCSCP(cp)) {
         dos.loaded_codepage = cp;
         if (CodePageHostToGuestUTF16((char *)cpcnv_ltemp,(const uint16_t *)s)) {
             dos.loaded_codepage = cpbak;
diff --git a/src/ints/bios_disk.cpp b/src/ints/bios_disk.cpp
index 9166dbb6b8..a087e6b921 100644
--- a/src/ints/bios_disk.cpp
+++ b/src/ints/bios_disk.cpp
@@ -41,7 +41,7 @@ extern const uint8_t freedos_mbr[];
 extern int bootdrive, tryconvertcp;
 extern bool int13_disk_change_detect_enable, skipintprog, rsize;
 extern bool int13_extensions_enable, bootguest, bootvm, use_quick_reboot;
-extern bool isDBCSCP(), isKanji1_gbk(uint8_t chr), shiftjis_lead_byte(int c);
+bool isDBCSCP(), isKanji1_gbk(uint8_t chr), shiftjis_lead_byte(int c), CheckDBCSCP(int32_t codepage);
 extern bool CodePageGuestToHostUTF16(uint16_t *d/*CROSS_LEN*/,const char *s/*CROSS_LEN*/);
 
 #define STATIC_ASSERTM(A,B) static_assertion_##A##_##B
@@ -514,7 +514,7 @@ struct fatFromDOSDrive
                         uint16_t uname[4];
 #if defined(WIN32)
                         uint16_t cp = GetACP(), cpbak = dos.loaded_codepage;
-                        if (tryconvertcp && cpbak == 437 && (cp == 932 || cp == 936 || cp == 949 || cp == 950 || cp == 951))
+                        if (tryconvertcp && cpbak == 437 && CheckDBCSCP(cp))
                             dos.loaded_codepage = cp;
 #endif
                         for (size_t i=0; i < lfnlen; i++) {
diff --git a/src/misc/messages.cpp b/src/misc/messages.cpp
index 67f6edbb02..fb87fbc78f 100644
--- a/src/misc/messages.cpp
+++ b/src/misc/messages.cpp
@@ -52,6 +52,7 @@ extern const char * RunningProgram;
 Bitu DOS_ChangeKeyboardLayout(const char* layoutname, int32_t codepage);
 Bitu DOS_ChangeCodepage(int32_t codepage, const char* codepagefile);
 Bitu DOS_LoadKeyboardLayout(const char* layoutname, int32_t codepage, const char* codepagefile);
+bool CheckDBCSCP(int32_t codepage);
 
 #define LINE_IN_MAXLEN 2048
 
@@ -204,12 +205,21 @@ void AddMessages() {
     MSG_Add("AUTO_CYCLE_OFF","Auto cycles [off]");
 }
 
+// True if specified codepage is a DBCS codepage
+bool CheckDBCSCP(int32_t codepage) {
+    if(codepage == 932 || codepage == 936 || codepage == 949 || codepage == 950 || codepage == 951) {
+        //LOG_MSG("CheckDBCSCP: Codepage %d true", codepage);
+        return true;
+    }
+    else return false;
+}
+
 void MSG_Init(void);
 void SetKEYBCP() {
     if (IS_PC98_ARCH || IS_JEGA_ARCH || IS_DOSV || dos_kernel_disabled || !strcmp(RunningProgram, "LOADLIN")) return;
     Bitu return_code;
 
-    if(msgcodepage == 932 || msgcodepage == 936 || msgcodepage == 949 || msgcodepage == 950 || msgcodepage == 951) {
+    if(CheckDBCSCP(msgcodepage)) {
         MSG_Init();
         InitFontHandle();
         JFONT_Init();
@@ -389,7 +399,7 @@ void LoadMessageFile(const char * fname) {
     dos.loaded_codepage=cp;
     if (loadlangcp && msgcodepage>0 && isSupportedCP(msgcodepage) && msgcodepage != dos.loaded_codepage) {
         ShutFontHandle();
-        if(msgcodepage == 932 || msgcodepage == 936 || msgcodepage == 949 || msgcodepage == 950 || msgcodepage == 951) {
+        if(CheckDBCSCP(msgcodepage)) {
             dos.loaded_codepage = msgcodepage;
             InitFontHandle();
             JFONT_Init();
@@ -486,7 +496,7 @@ void MSG_Init() {
                 sprintf(cstr, "%s,%d", countrystr, msgcodepage);
                 SetVal("config", "country", cstr);
                 const char *imestr = section->Get_string("ime");
-                if (tonoime && !strcasecmp(imestr, "auto") && (msgcodepage == 932 || msgcodepage == 936 || msgcodepage == 949 || msgcodepage == 950 || msgcodepage == 951)) {
+                if (tonoime && !strcasecmp(imestr, "auto") && CheckDBCSCP(msgcodepage)) {
                     tonoime = false;
                     enableime = true;
                     SetIME();
diff --git a/src/output/output_ttf.cpp b/src/output/output_ttf.cpp
index 110efdcf3e..4216b148e7 100644
--- a/src/output/output_ttf.cpp
+++ b/src/output/output_ttf.cpp
@@ -125,6 +125,7 @@ bool init_once = false, init_twice = false;
 int menuwidth_atleast(int width), FileDirExistCP(const char *name), FileDirExistUTF8(std::string &localname, const char *name);
 void AdjustIMEFontSize(void),refreshExtChar(void), initcodepagefont(void), change_output(int output), drawmenu(Bitu val), KEYBOARD_Clear(void), RENDER_Reset(void), DOSBox_SetSysMenu(void), GetMaxWidthHeight(unsigned int *pmaxWidth, unsigned int *pmaxHeight), SetWindowTransparency(int trans), resetFontSize(void), RENDER_CallBack( GFX_CallBackFunctions_t function );
 bool isDBCSCP(void), InitCodePage(void), CodePageGuestToHostUTF16(uint16_t *d/*CROSS_LEN*/,const char *s/*CROSS_LEN*/), systemmessagebox(char const * aTitle, char const * aMessage, char const * aDialogType, char const * aIconType, int aDefaultButton);
+bool CheckDBCSCP(int32_t codepage);
 std::string GetDOSBoxXPath(bool withexe=false);
 
 #if defined(C_SDL2)
@@ -502,14 +503,14 @@ int setTTFMap(bool changecp) {
         uname[0]=0;
         uname[1]=0;
         if (cp == 932 && (halfwidthkana || IS_JEGA_ARCH)) forceswk=true;
-        if (cp == 932 || cp == 936 || cp == 949 || cp == 950 || cp == 951) dos.loaded_codepage = 437;
+        if (CheckDBCSCP(cp)) dos.loaded_codepage = 437;
         if (CodePageGuestToHostUTF16(uname,text)) {
             wcTest[i] = uname[1]==0?uname[0]:i;
             if (cp == 932 && lowboxdrawmap.find(i)!=lowboxdrawmap.end() && TTF_GlyphIsProvided(ttf.SDL_font, wcTest[i]))
                 cpMap[i] = wcTest[i];
         }
         forceswk=false;
-        if (cp == 932 || cp == 936 || cp == 949 || cp == 950 || cp == 951) dos.loaded_codepage = cp;
+        if (CheckDBCSCP(cp)) dos.loaded_codepage = cp;
     }
     uint16_t unimap;
     int notMapped = 0;
diff --git a/src/shell/shell_cmds.cpp b/src/shell/shell_cmds.cpp
index 93cde79a97..b7718b8085 100644
--- a/src/shell/shell_cmds.cpp
+++ b/src/shell/shell_cmds.cpp
@@ -140,6 +140,7 @@ extern void MAPPER_AutoType(std::vector<std::string> &sequence, const uint32_t w
 extern void DOS_SetCountry(uint16_t countryNo), DOSV_FillScreen(void);
 std::string GetDOSBoxXPath(bool withexe=false);
 FILE *testLoadLangFile(const char *fname);
+bool CheckDBCSCP(int32_t codepage);
 
 /* support functions */
 static char empty_char = 0;
@@ -4599,7 +4600,7 @@ void DOS_Shell::CMD_CHCP(char * args) {
     int32_t cp = dos.loaded_codepage;
     Bitu keyb_error;
     if(n == 1) {
-        if(newCP == 932 || newCP == 936 || newCP == 949 || newCP == 950 || newCP == 951
+        if(CheckDBCSCP(newCP)
 #if defined(USE_TTF)
             || (ttf.inUse && (newCP >= 1250 && newCP <= 1258))
 #endif
@@ -4636,7 +4637,7 @@ void DOS_Shell::CMD_CHCP(char * args) {
         if(*buff == ':' && strchr(StripArg(args), ':')) {
             std::string name = buff + 1;
             if(name.empty() && iter != langcp_map.end()) name = iter->second;
-            if(newCP == 932 || newCP == 936 || newCP == 949 || newCP == 950 || newCP == 951) {
+            if(CheckDBCSCP(newCP)) {
                 missing = toSetCodePage(this, newCP, -1);
                 if(missing > -1) SwitchLanguage(cp, newCP, true);
                 if(missing > 0) WriteOut(MSG_Get("SHELL_CMD_CHCP_MISSING"), missing);

From f3847d7df9dd435afd5ddb4dd2928ca7ec56baf8 Mon Sep 17 00:00:00 2001
From: maron2000 <68574602+maron2000@users.noreply.github.com>
Date: Sat, 5 Oct 2024 10:35:34 +0900
Subject: [PATCH 02/10] toSetCodePage function switches codepages in non-TTF
 mode and in non-DBCS codepages

---
 src/shell/shell_cmds.cpp | 16 ++++++++++++----
 1 file changed, 12 insertions(+), 4 deletions(-)

diff --git a/src/shell/shell_cmds.cpp b/src/shell/shell_cmds.cpp
index b7718b8085..00815b7e55 100644
--- a/src/shell/shell_cmds.cpp
+++ b/src/shell/shell_cmds.cpp
@@ -140,7 +140,9 @@ extern void MAPPER_AutoType(std::vector<std::string> &sequence, const uint32_t w
 extern void DOS_SetCountry(uint16_t countryNo), DOSV_FillScreen(void);
 std::string GetDOSBoxXPath(bool withexe=false);
 FILE *testLoadLangFile(const char *fname);
+Bitu DOS_ChangeCodepage(int32_t codepage, const char* codepagefile);
 bool CheckDBCSCP(int32_t codepage);
+static int32_t lastsetcp = 0;
 
 /* support functions */
 static char empty_char = 0;
@@ -4527,14 +4529,16 @@ extern bool jfont_init, isDBCSCP();
 extern Bitu DOS_LoadKeyboardLayout(const char * layoutname, int32_t codepage, const char * codepagefile);
 void runRescan(const char *str), MSG_Init(), JFONT_Init(), InitFontHandle(), ShutFontHandle(), initcodepagefont(), DOSBox_SetSysMenu();
 int toSetCodePage(DOS_Shell *shell, int newCP, int opt) {
-    if (isSupportedCP(newCP)) {
-		dos.loaded_codepage = newCP;
+    if((TTF_using() && isSupportedCP(newCP)) || !TTF_using()) {
+        if(!CheckDBCSCP(newCP)) DOS_ChangeCodepage(newCP, "auto");
+        dos.loaded_codepage = newCP;
         int missing = 0;
 #if defined(USE_TTF)
 		missing = TTF_using() ? setTTFCodePage() : 0;
 #endif
         if (!TTF_using()) initcodepagefont();
-        if (dos.loaded_codepage==437) DOS_LoadKeyboardLayout("us", 437, "auto");
+        //if (dos.loaded_codepage==437) DOS_LoadKeyboardLayout("us", 437, "auto");
+        //LOG_MSG("toSetCodePage opt=%d, loadlangnew=%d", opt, loadlangnew?1:0);
         if (opt==-1) {
             MSG_Init();
 #if DOSBOXMENU_TYPE == DOSBOXMENU_HMENU
@@ -4550,8 +4554,8 @@ int toSetCodePage(DOS_Shell *shell, int newCP, int opt) {
             ShutFontHandle();
             InitFontHandle();
             JFONT_Init();
+            SetupDBCSTable();
         }
-        SetupDBCSTable();
         runRescan("-A -Q");
 #if defined(USE_TTF)
         if ((opt==-1||opt==-2)&&TTF_using()) {
@@ -4565,6 +4569,10 @@ int toSetCodePage(DOS_Shell *shell, int newCP, int opt) {
             }
         }
 #endif
+        if(newCP != lastsetcp) {
+            LOG_MSG("Codepage set to %d", newCP);
+            lastsetcp = newCP;
+        }
         return missing;
     } else if (opt<1 && shell) {
        shell->WriteOut(MSG_Get("SHELL_CMD_CHCP_INVALID"), std::to_string(newCP).c_str());

From 2205c844a14aedc39a1bf36ff127f33252c34ef2 Mon Sep 17 00:00:00 2001
From: maron2000 <68574602+maron2000@users.noreply.github.com>
Date: Sat, 5 Oct 2024 11:39:41 +0900
Subject: [PATCH 03/10] Fix initial loading of Chinese & Korean keyboard
 layouts

---
 src/dos/dos_keyboard_layout.cpp | 88 +++++++++++++++------------------
 1 file changed, 40 insertions(+), 48 deletions(-)

diff --git a/src/dos/dos_keyboard_layout.cpp b/src/dos/dos_keyboard_layout.cpp
index 2f465d1d0c..234e7bd3bb 100644
--- a/src/dos/dos_keyboard_layout.cpp
+++ b/src/dos/dos_keyboard_layout.cpp
@@ -1447,11 +1447,11 @@ class DOS_KeyboardLayout: public Module_base {
         const Section_prop* section = static_cast<Section_prop*>(configuration);
 		const char * layoutname=section->Get_string("keyboardlayout");
 		dos.loaded_codepage = GetDefaultCP();	// default codepage already initialized
-        int tocp=!strcmp(layoutname, "jp")||IS_JDOSV?932:(!strcmp(layoutname, "ko")||IS_KDOSV?949:(!strcmp(layoutname, "tw")||!strcmp(layoutname, "hk")||!strcmp(layoutname, "zht")||IS_TDOSV?950:(!strcmp(layoutname, "cn")||!strcmp(layoutname, "zh")||!strcmp(layoutname, "zhs")||IS_PDOSV?936:(!strcmp(layoutname, "us")?437:0))));
+        int tocp=!stricmp(layoutname, "jp")||IS_JDOSV?932:(!stricmp(layoutname, "ko")||IS_KDOSV?949:(!stricmp(layoutname, "tw")||!stricmp(layoutname, "hk")||!stricmp(layoutname, "zht")||IS_TDOSV?950:(!stricmp(layoutname, "cn")||!stricmp(layoutname, "zh")||!stricmp(layoutname, "zhs")||IS_PDOSV?936:(!stricmp(layoutname, "us")?437:0))));
 #if defined(WIN32)
 		if (dos.loaded_codepage == 932 && !IS_PC98_ARCH && GetKeyboardType(0) == 7 && !strcmp(layoutname, "auto")) layoutname = "jp106";
 #endif
-        if (tocp && strcmp(layoutname, "jp106") && strcmp(layoutname, "jp") && strcmp(layoutname, "ko")) layoutname="us";
+        if (tocp && stricmp(layoutname, "jp106") && stricmp(layoutname, "jp") && stricmp(layoutname, "ko") && stricmp(layoutname, "cn") && stricmp(layoutname, "hk") && stricmp(layoutname, "tw")) layoutname="us";
 
 #if defined(USE_TTF)
         if (TTF_using()) setTTFCodePage(); else
@@ -1487,11 +1487,9 @@ class DOS_KeyboardLayout: public Module_base {
 					layoutname = "bg241";
 					break; */
 				case 1028: // Taiwan, CP 950, Alt CP 951
-					if (tryconvertcp == 1) {
-						layoutname = "us";
-						tocp = 950;
-					}
-					break;
+                    layoutname = "us";
+                    tocp = 950;
+                    break;
 				case 1029: // Czech Republic, CP 852, Alt CP 850
 					layoutname = "cz243";
 					break;
@@ -1533,17 +1531,13 @@ class DOS_KeyboardLayout: public Module_base {
 					wants_dos_codepage = GetDefaultCP();
 					break;
 				case 1041: // Japan, CP 932
-					if (tryconvertcp == 1) {
-						layoutname = "jp";
-						tocp = 932;
-					}
-					break;
+                    layoutname = "jp";
+                    tocp = 932;
+                    break;
 				case 1042: // Korea, CP 949
-					if (tryconvertcp == 1) {
-						layoutname = "ko";
-						tocp = 949;
-					}
-					break;
+                    layoutname = "us";
+                    tocp = 949;
+                    break;
 				case 1043: // Netherlands, CP 850, Alt CP 437
 					layoutname = "nl";
 					wants_dos_codepage = GetDefaultCP();
@@ -1610,11 +1604,9 @@ class DOS_KeyboardLayout: public Module_base {
 					layoutname = "hy";
 					break; */
 				case 2052: // China, CP 936
-					if (tryconvertcp == 1) {
-						layoutname = "us";
-						tocp = 936;
-					}
-					break;
+                    layoutname = "us";
+                    tocp = 936;
+                    break;
 				case 2055: // Swiss-German, CP 850, Alt CP 437
 					layoutname = "sg";
 					wants_dos_codepage = GetDefaultCP();
@@ -1639,11 +1631,9 @@ class DOS_KeyboardLayout: public Module_base {
 					layoutname = "po";
 					break;
 				case 3076: // Hong Kong, CP 950, Alt CP 951
-					if (tryconvertcp == 1) {
-						layoutname = "us";
-						tocp = 950;
-					}
-					break;
+                    layoutname = "us";
+                    tocp = 950;
+                    break;
 				case 3081: // Australia, CP 850, Alt CP 437
 					layoutname = "us"; 
 					wants_dos_codepage = GetDefaultCP();
@@ -1681,13 +1671,18 @@ class DOS_KeyboardLayout: public Module_base {
 					wants_dos_codepage = GetDefaultCP();
 					break;
 				default:
-					break;
+                    layoutname = "us";
+                    wants_dos_codepage = 437;
+                    break;
 			}
-		}
-        else if(!strncmp(layoutname, "none", 4)) {
+#else // !WIN32
             layoutname = "us";
             wants_dos_codepage = 437;
 #endif
+        }
+        else if(!strncmp(layoutname, "none", 4)) {
+            layoutname = "us";
+            wants_dos_codepage = 437;
         }
 
 		bool extract_codepage = !tocp;
@@ -1706,8 +1701,14 @@ class DOS_KeyboardLayout: public Module_base {
 /*		if (strncmp(layoutname,"auto",4) && strncmp(layoutname,"none",4)) {
 			LOG_MSG("Loading DOS keyboard layout %s ...",layoutname);
 		} */
-		if (!tocp && loaded_layout->read_keyboard_file(layoutname, dos.loaded_codepage)) {
-			if (strncmp(layoutname,"auto",4)) {
+        if(!stricmp(layoutname, "cn") || !stricmp(layoutname, "hk") || !stricmp(layoutname, "tw") || !stricmp(layoutname, "ko")) {
+            loaded_layout->read_keyboard_file("us", 437);
+            if(!stricmp(layoutname, "cn")) dos.loaded_codepage = 936;
+            if(!stricmp(layoutname, "hk") || !stricmp(layoutname, "tw")) dos.loaded_codepage = 950;
+            if(!stricmp(layoutname, "ko")) dos.loaded_codepage = 949;
+        }
+        if (!tocp && loaded_layout->read_keyboard_file(layoutname, dos.loaded_codepage)) {
+            if (strncmp(layoutname,"auto",4)) {
 				LOG_MSG("Error loading keyboard layout %s",layoutname);
 			}
 		} else if (!tocp) {
@@ -1717,20 +1718,15 @@ class DOS_KeyboardLayout: public Module_base {
 			}
 		}
         if (tocp && !IS_PC98_ARCH) {
-            if((dos.loaded_codepage == 932 || tocp == 932) && (!strcmp(layoutname, "jp106") || !strcmp(layoutname, "jp"))) loaded_layout->read_keyboard_file(layoutname, 932);
-
             uint16_t cpbak = dos.loaded_codepage;
-#if defined(USE_TTF)
-            if (ttf.inUse)
-                toSetCodePage(NULL, tocp, -1);
-            else
-#endif
-            {
+            if((dos.loaded_codepage == 932 || tocp == 932) && (!stricmp(layoutname, "jp106") || !stricmp(layoutname, "jp"))) loaded_layout->read_keyboard_file(layoutname, 932);
+            if(!stricmp(layoutname, "ko") || !stricmp(layoutname, "cn") || !stricmp(layoutname, "tw") || !stricmp(layoutname, "hk")) {
+                loaded_layout->read_keyboard_file("us", 437);
                 dos.loaded_codepage = tocp;
-                MSG_Init();
-                DOSBox_SetSysMenu();
-                if (!jfont_init && isDBCSCP()) JFONT_Init();
-                SetupDBCSTable();
+            }
+
+            if (!TTF_using() || (TTF_using() && isSupportedCP(tocp))){
+                toSetCodePage(NULL, msgcodepage ? msgcodepage : tocp, -2);
                 runRescan("-A -Q");
 #if C_OPENGL && DOSBOXMENU_TYPE == DOSBOXMENU_SDLDRAW
                 if (OpenGL_using() && control->opt_lang.size() && lastcp && lastcp != dos.loaded_codepage)
@@ -1738,10 +1734,6 @@ class DOS_KeyboardLayout: public Module_base {
 #endif
             }
         }
-        if(msgcodepage) {
-            SwitchLanguage(dos.loaded_codepage, msgcodepage, false);
-            DOS_ChangeCodepage(msgcodepage, "auto");
-        }
     }
 
 	~DOS_KeyboardLayout(){

From 9447b8d2032353d72734a7e4bf8160f506b38d86 Mon Sep 17 00:00:00 2001
From: maron2000 <68574602+maron2000@users.noreply.github.com>
Date: Sat, 5 Oct 2024 12:58:08 +0900
Subject: [PATCH 04/10] CHCP: Fix handling of invalid codepage

---
 src/dos/dos.cpp                 |  2 +-
 src/dos/dos_keyboard_layout.cpp | 11 +++----
 src/dos/dos_programs.cpp        |  8 +++--
 src/misc/messages.cpp           |  4 +--
 src/shell/shell.cpp             |  2 +-
 src/shell/shell_cmds.cpp        | 53 +++++++++++++++++----------------
 6 files changed, 43 insertions(+), 37 deletions(-)

diff --git a/src/dos/dos.cpp b/src/dos/dos.cpp
index e95dfea0ff..5a05f827d9 100644
--- a/src/dos/dos.cpp
+++ b/src/dos/dos.cpp
@@ -90,7 +90,7 @@ bool isDBCSCP();
 uint32_t BIOS_get_PC98_INT_STUB(void);
 uint16_t GetDefaultCP(void);
 void ResolvePath(std::string& in);
-void SwitchLanguage(int oldcp, int newcp, bool confirm);
+bool SwitchLanguage(int oldcp, int newcp, bool confirm);
 void makestdcp950table(), makeseacp951table();
 std::string GetDOSBoxXPath(bool withexe=false);
 extern std::string prefix_local, prefix_overlay;
diff --git a/src/dos/dos_keyboard_layout.cpp b/src/dos/dos_keyboard_layout.cpp
index 234e7bd3bb..0c88e72dc7 100644
--- a/src/dos/dos_keyboard_layout.cpp
+++ b/src/dos/dos_keyboard_layout.cpp
@@ -48,7 +48,6 @@ int lastcp = 0;
 void DOSBox_SetSysMenu(void);
 bool OpenGL_using(void), isDBCSCP(void);
 void change_output(int output), UpdateSDLDrawTexture();
-void SwitchLanguage(int oldcp, int newcp, bool confirm);
 Bitu DOS_ChangeCodepage(int32_t codepage, const char* codepagefile);
 void MSG_Init(), JFONT_Init(), runRescan(const char *str);
 extern int tryconvertcp, toSetCodePage(DOS_Shell *shell, int newCP, int opt);
@@ -1425,8 +1424,10 @@ Bitu DOS_ChangeKeyboardLayout(const char* layoutname, int32_t codepage) {
 
 Bitu DOS_ChangeCodepage(int32_t codepage, const char* codepagefile) {
     // try to read the layout for the specified codepage
+    int32_t oldcp = dos.loaded_codepage;
     Bitu kerrcode = loaded_layout->read_codepage_file(codepagefile, codepage);
     if(kerrcode) {
+        loaded_layout->read_codepage_file("auto", oldcp);
         return kerrcode;
     }
     // Everything went fine
@@ -1487,7 +1488,7 @@ class DOS_KeyboardLayout: public Module_base {
 					layoutname = "bg241";
 					break; */
 				case 1028: // Taiwan, CP 950, Alt CP 951
-                    layoutname = "us";
+                    layoutname = "tw";
                     tocp = 950;
                     break;
 				case 1029: // Czech Republic, CP 852, Alt CP 850
@@ -1535,7 +1536,7 @@ class DOS_KeyboardLayout: public Module_base {
                     tocp = 932;
                     break;
 				case 1042: // Korea, CP 949
-                    layoutname = "us";
+                    layoutname = "ko";
                     tocp = 949;
                     break;
 				case 1043: // Netherlands, CP 850, Alt CP 437
@@ -1604,7 +1605,7 @@ class DOS_KeyboardLayout: public Module_base {
 					layoutname = "hy";
 					break; */
 				case 2052: // China, CP 936
-                    layoutname = "us";
+                    layoutname = "cn";
                     tocp = 936;
                     break;
 				case 2055: // Swiss-German, CP 850, Alt CP 437
@@ -1631,7 +1632,7 @@ class DOS_KeyboardLayout: public Module_base {
 					layoutname = "po";
 					break;
 				case 3076: // Hong Kong, CP 950, Alt CP 951
-                    layoutname = "us";
+                    layoutname = "hk";
                     tocp = 950;
                     break;
 				case 3081: // Australia, CP 850, Alt CP 437
diff --git a/src/dos/dos_programs.cpp b/src/dos/dos_programs.cpp
index e92ffc5ab9..4fad572a35 100644
--- a/src/dos/dos_programs.cpp
+++ b/src/dos/dos_programs.cpp
@@ -114,6 +114,7 @@ void runBoot(const char *str), runMount(const char *str), runImgmount(const char
 void getdrivezpath(std::string &path, std::string const& dirname), drivezRegister(std::string const& path, std::string const& dir, bool usecp), UpdateDefaultPrinterFont(void);
 std::string GetDOSBoxXPath(bool withexe=false);
 FILE *testLoadLangFile(const char *fname);
+bool CheckDBCSCP(int32_t codepage);
 
 #if defined(OS2)
 #define INCL DOSFILEMGR
@@ -206,8 +207,7 @@ void DetachFromBios(imageDisk* image) {
     }
 }
 
-void SwitchLanguage(int oldcp, int newcp, bool confirm) {
-    (void)oldcp; //unused
+bool SwitchLanguage(int oldcp, int newcp, bool confirm) {
     auto iterold = langcp_map.find(lastmsgcp), iternew = langcp_map.find(newcp);
     std::string langold = iterold != langcp_map.end() ? iterold->second : "", langnew = iternew != langcp_map.end() ? iternew->second : "";
     if (loadlang && langnew.size() && strcasecmp(langold.c_str(), langnew.c_str())) {
@@ -215,13 +215,15 @@ void SwitchLanguage(int oldcp, int newcp, bool confirm) {
         if (file) {
             fclose(file);
             std::string msg = "You have changed the active code page to " + std::to_string(newcp) + ". Do you want to load language file " + langnew + " for this code page?";
-            if (!confirm || systemmessagebox("DOSBox-X language file", msg.c_str(), "yesno","question", 2)) {
+            if (!confirm || (CheckDBCSCP(oldcp) && !CheckDBCSCP(newcp)) || systemmessagebox("DOSBox-X language file", msg.c_str(), "yesno","question", 2)) {
                 SetVal("dosbox", "language", langnew);
                 Load_Language(langnew);
                 lastmsgcp = newcp;
+                return true; // Will load language file for the active codepage
             }
         }
     }
+    return false;
 }
 
 extern std::string hidefiles, dosbox_title;
diff --git a/src/misc/messages.cpp b/src/misc/messages.cpp
index fb87fbc78f..f92043d62c 100644
--- a/src/misc/messages.cpp
+++ b/src/misc/messages.cpp
@@ -46,7 +46,7 @@ bool isSupportedCP(int newCP), CodePageHostToGuestUTF8(char *d/*CROSS_LEN*/,cons
 void InitFontHandle(void), ShutFontHandle(void), refreshExtChar(void), SetIME(void), runRescan(const char *str), menu_update_dynamic(void), menu_update_autocycle(void), update_bindbutton_text(void), set_eventbutton_text(const char *eventname, const char *buttonname), JFONT_Init(), DOSBox_SetSysMenu(), UpdateSDLDrawTexture(), makestdcp950table(), makeseacp951table();
 std::string langname = "", langnote = "", GetDOSBoxXPath(bool withexe=false);
 extern int lastcp, FileDirExistUTF8(std::string &localname, const char *name), toSetCodePage(DOS_Shell *shell, int newCP, int opt);
-extern bool dos_kernel_disabled, force_conversion, showdbcs, dbcs_sbcs, enableime, tonoime, chinasea;
+extern bool dos_kernel_disabled, force_conversion, showdbcs, dbcs_sbcs, enableime, tonoime, chinasea, CHCP_changed;
 extern uint16_t GetDefaultCP();
 extern const char * RunningProgram;
 Bitu DOS_ChangeKeyboardLayout(const char* layoutname, int32_t codepage);
@@ -335,7 +335,7 @@ void LoadMessageFile(const char * fname) {
                         }
                         else {
                             std::string msg = "The specified language file uses code page " + std::to_string(c) + ". Do you want to change to this code page accordingly?";
-                            if(c != dos.loaded_codepage && (control->opt_langcp || uselangcp || !loadlang || (loadlang && systemmessagebox("DOSBox-X language file", msg.c_str(), "yesno", "question", 1)))){
+                            if(c != dos.loaded_codepage && (control->opt_langcp || uselangcp || !CHCP_changed || !loadlang || (loadlang && systemmessagebox("DOSBox-X language file", msg.c_str(), "yesno", "question", 1)))){
                                 loadlangcp = true;
                                 msgcodepage = c;
                                 dos.loaded_codepage = c;
diff --git a/src/shell/shell.cpp b/src/shell/shell.cpp
index 8e30e14219..eb16b07e72 100644
--- a/src/shell/shell.cpp
+++ b/src/shell/shell.cpp
@@ -77,7 +77,7 @@ void initcodepagefont(void);
 void runMount(const char *str);
 void ResolvePath(std::string& in);
 void DOS_SetCountry(uint16_t countryNo);
-void SwitchLanguage(int oldcp, int newcp, bool confirm);
+bool SwitchLanguage(int oldcp, int newcp, bool confirm);
 void CALLBACK_DeAllocate(Bitu in), DOSBox_ConsolePauseWait();
 void GFX_SetTitle(int32_t cycles, int frameskip, Bits timing, bool paused);
 bool isDBCSCP(), InitCodePage(), isKanji1(uint8_t chr), shiftjis_lead_byte(int c), sdl_wait_on_error();
diff --git a/src/shell/shell_cmds.cpp b/src/shell/shell_cmds.cpp
index 00815b7e55..189547bc14 100644
--- a/src/shell/shell_cmds.cpp
+++ b/src/shell/shell_cmds.cpp
@@ -135,14 +135,15 @@ extern uint16_t countryNo, altcp_to_unicode[256];
 extern bool isDBCSCP(), isKanji1(uint8_t chr), shiftjis_lead_byte(int c), TTF_using(void), Network_IsNetworkResource(const char * filename);
 extern bool CheckBoxDrawing(uint8_t c1, uint8_t c2, uint8_t c3, uint8_t c4), GFX_GetPreventFullscreen(void), DOS_SetAnsiAttr(uint8_t attr);
 extern bool systemmessagebox(char const * aTitle, char const * aMessage, char const * aDialogType, char const * aIconType, int aDefaultButton);
-extern void Load_Language(std::string name), SwitchLanguage(int oldcp, int newcp, bool confirm), GetExpandedPath(std::string &path);
+extern void Load_Language(std::string name), GetExpandedPath(std::string &path);
 extern void MAPPER_AutoType(std::vector<std::string> &sequence, const uint32_t wait_ms, const uint32_t pace_ms, bool choice);
 extern void DOS_SetCountry(uint16_t countryNo), DOSV_FillScreen(void);
 std::string GetDOSBoxXPath(bool withexe=false);
 FILE *testLoadLangFile(const char *fname);
 Bitu DOS_ChangeCodepage(int32_t codepage, const char* codepagefile);
-bool CheckDBCSCP(int32_t codepage);
+bool CheckDBCSCP(int32_t codepage), SwitchLanguage(int oldcp, int newcp, bool confirm);
 static int32_t lastsetcp = 0;
+bool CHCP_changed = false;
 
 /* support functions */
 static char empty_char = 0;
@@ -4530,8 +4531,18 @@ extern Bitu DOS_LoadKeyboardLayout(const char * layoutname, int32_t codepage, co
 void runRescan(const char *str), MSG_Init(), JFONT_Init(), InitFontHandle(), ShutFontHandle(), initcodepagefont(), DOSBox_SetSysMenu();
 int toSetCodePage(DOS_Shell *shell, int newCP, int opt) {
     if((TTF_using() && isSupportedCP(newCP)) || !TTF_using()) {
-        if(!CheckDBCSCP(newCP)) DOS_ChangeCodepage(newCP, "auto");
-        dos.loaded_codepage = newCP;
+        int32_t oldcp = dos.loaded_codepage;
+        Bitu keyb_error;
+        if (!CheckDBCSCP(newCP)){
+            keyb_error = DOS_ChangeCodepage(newCP, "auto");
+            if (keyb_error != KEYB_NOERROR) {
+                dos.loaded_codepage = oldcp;
+                return -1;
+            }
+        }
+        else {
+            dos.loaded_codepage = newCP;
+        }
         int missing = 0;
 #if defined(USE_TTF)
 		missing = TTF_using() ? setTTFCodePage() : 0;
@@ -4608,37 +4619,29 @@ void DOS_Shell::CMD_CHCP(char * args) {
     int32_t cp = dos.loaded_codepage;
     Bitu keyb_error;
     if(n == 1) {
-        if(CheckDBCSCP(newCP)
-#if defined(USE_TTF)
-            || (ttf.inUse && (newCP >= 1250 && newCP <= 1258))
-#endif
-            ) {
-            missing = toSetCodePage(this, newCP, -1);
-            if(missing > -1) SwitchLanguage(cp, newCP, true);
+        if (!TTF_using() || (TTF_using() && isSupportedCP(newCP))){
+            bool load_language = SwitchLanguage(cp, newCP, true);
+            CHCP_changed = true;
+            missing = toSetCodePage(this, newCP, load_language ? -1: -2);
             if(missing > 0) WriteOut(MSG_Get("SHELL_CMD_CHCP_MISSING"), missing);
+            else if(missing < 0) {
+                WriteOut(MSG_Get("SHELL_CMD_CHCP_INVALID"), StripArg(args));
+                CHCP_changed = false;
+                return;
+            }
         }
         else {
-#if defined(USE_TTF)
-            if(ttf.inUse && !isSupportedCP(newCP)) {
+            if(TTF_using() && !isSupportedCP(newCP)) {
                 WriteOut(MSG_Get("SHELL_CMD_CHCP_INVALID"), StripArg(args));
                 LOG_MSG("CHCP: Codepage %d not supported for TTF output", newCP);
-                return;
-            }
-#endif
-            keyb_error = DOS_ChangeCodepage(newCP, "auto");
-            if(keyb_error == KEYB_NOERROR) {
-                SwitchLanguage(cp, newCP, true);
-/**
-                if(layout_name != NULL) {
-                    keyb_error = DOS_ChangeKeyboardLayout(layout_name, cp);
-                }
-*/
             }
             else {
                 WriteOut(MSG_Get("SHELL_CMD_CHCP_INVALID"), StripArg(args));
-                return;
             }
+            CHCP_changed = false;
+            return;
         }
+        CHCP_changed = false;
         WriteOut(MSG_Get("SHELL_CMD_CHCP_ACTIVE"), dos.loaded_codepage);
     }
     else if(n == 2 && strlen(buff)) {

From a205b99ad3549175efd719515c56c7f2d869d88e Mon Sep 17 00:00:00 2001
From: maron2000 <68574602+maron2000@users.noreply.github.com>
Date: Sat, 5 Oct 2024 14:18:46 +0900
Subject: [PATCH 05/10] Remove some redundant codes in CHCP command

---
 src/misc/programs.cpp    |  4 +++-
 src/shell/shell_cmds.cpp | 30 ++++++------------------------
 2 files changed, 9 insertions(+), 25 deletions(-)

diff --git a/src/misc/programs.cpp b/src/misc/programs.cpp
index ee27e63ae9..b5e4c986d0 100644
--- a/src/misc/programs.cpp
+++ b/src/misc/programs.cpp
@@ -726,7 +726,7 @@ void dos_ver_menu(bool start), ReloadMapper(Section_prop *sec, bool init), SetGa
 bool set_ver(char *s), GFX_IsFullscreen(void);
 
 void Load_Language(std::string name) {
-    if (control->opt_lang != "") control->opt_lang = name;
+    control->opt_lang = name;
     MSG_Init();
 #if DOSBOXMENU_TYPE == DOSBOXMENU_HMENU || DOSBOXMENU_TYPE == DOSBOXMENU_NSMENU
     mainMenu.unbuild();
@@ -738,12 +738,14 @@ void Load_Language(std::string name) {
 #if defined(USE_TTF)
     if (TTF_using()) resetFontSize();
 #endif
+#if 0
     if (!uselangcp && !incall) {
         int oldmsgcp = msgcodepage;
         msgcodepage = dos.loaded_codepage;
         SetKEYBCP();
         msgcodepage = oldmsgcp;
     }
+#endif
 }
 
 void ApplySetting(std::string pvar, std::string inputline, bool quiet) {
diff --git a/src/shell/shell_cmds.cpp b/src/shell/shell_cmds.cpp
index 189547bc14..adb98b2f75 100644
--- a/src/shell/shell_cmds.cpp
+++ b/src/shell/shell_cmds.cpp
@@ -4648,40 +4648,22 @@ void DOS_Shell::CMD_CHCP(char * args) {
         if(*buff == ':' && strchr(StripArg(args), ':')) {
             std::string name = buff + 1;
             if(name.empty() && iter != langcp_map.end()) name = iter->second;
-            if(CheckDBCSCP(newCP)) {
+            if(!TTF_using() || (TTF_using() && isSupportedCP(newCP))) {
+                CHCP_changed = true;
                 missing = toSetCodePage(this, newCP, -1);
-                if(missing > -1) SwitchLanguage(cp, newCP, true);
                 if(missing > 0) WriteOut(MSG_Get("SHELL_CMD_CHCP_MISSING"), missing);
-            }
-#if defined(USE_TTF)
-            else if(ttf.inUse) {
-                if(newCP >= 1250 && newCP <= 1258) {
-                    missing = toSetCodePage(this, newCP, -1);
-                    if(missing > -1) SwitchLanguage(cp, newCP, true);
-                    if(missing > 0) WriteOut(MSG_Get("SHELL_CMD_CHCP_MISSING"), missing);
-                }
-                else if(!isSupportedCP(newCP)) {
+                else if(missing < 0) {
                     WriteOut(MSG_Get("SHELL_CMD_CHCP_INVALID"), StripArg(args));
-                    LOG_MSG("CHCP: Codepage %d not supported for TTF output", newCP);
+                    CHCP_changed = false;
                     return;
                 }
             }
-#endif
-            else {
-                keyb_error = DOS_ChangeCodepage(newCP, "auto");
-                if(keyb_error == KEYB_NOERROR) {
-                    if(layout_name != NULL) {
-                        keyb_error = DOS_ChangeKeyboardLayout(layout_name, cp);
-                    }
-                }
-                else
-                    WriteOut(MSG_Get("SHELL_CMD_CHCP_INVALID"), StripArg(args));
-            }
             if(name.size() && dos.loaded_codepage == newCP) {
                 SetVal("dosbox", "language", name);
                 Load_Language(name);
             }
             WriteOut(MSG_Get("SHELL_CMD_CHCP_ACTIVE"), dos.loaded_codepage);
+            CHCP_changed = false;
             return;
         }
 #if defined(USE_TTF)
@@ -4706,7 +4688,7 @@ void DOS_Shell::CMD_CHCP(char * args) {
             FILE* file = fopen(cpfile.c_str(), "r"); /* should check the result */
             std::string exepath = GetDOSBoxXPath();
             if(!file && exepath.size()) file = fopen((exepath + CROSS_FILESPLIT + cpfile).c_str(), "r");
-            if(file && newCP > 0 && newCP != 932 && newCP != 936 && newCP != 949 && newCP != 950 && newCP != 951) {
+            if(file && newCP > 0 && !CheckDBCSCP(newCP)) {
                 altcp = newCP;
                 char line[256], * l = line;
                 while(fgets(line, sizeof(line), file)) {

From 0be59ed77a2117e64202abf662da24acfc75994a Mon Sep 17 00:00:00 2001
From: maron2000 <68574602+maron2000@users.noreply.github.com>
Date: Sat, 5 Oct 2024 16:09:29 +0900
Subject: [PATCH 06/10] Fix build error

---
 src/dos/dos_keyboard_layout.cpp | 18 +++++++++---------
 1 file changed, 9 insertions(+), 9 deletions(-)

diff --git a/src/dos/dos_keyboard_layout.cpp b/src/dos/dos_keyboard_layout.cpp
index 0c88e72dc7..c9a362e5e2 100644
--- a/src/dos/dos_keyboard_layout.cpp
+++ b/src/dos/dos_keyboard_layout.cpp
@@ -1448,11 +1448,11 @@ class DOS_KeyboardLayout: public Module_base {
         const Section_prop* section = static_cast<Section_prop*>(configuration);
 		const char * layoutname=section->Get_string("keyboardlayout");
 		dos.loaded_codepage = GetDefaultCP();	// default codepage already initialized
-        int tocp=!stricmp(layoutname, "jp")||IS_JDOSV?932:(!stricmp(layoutname, "ko")||IS_KDOSV?949:(!stricmp(layoutname, "tw")||!stricmp(layoutname, "hk")||!stricmp(layoutname, "zht")||IS_TDOSV?950:(!stricmp(layoutname, "cn")||!stricmp(layoutname, "zh")||!stricmp(layoutname, "zhs")||IS_PDOSV?936:(!stricmp(layoutname, "us")?437:0))));
+        int tocp=!strcmp(layoutname, "jp")||IS_JDOSV?932:(!strcmp(layoutname, "ko")||IS_KDOSV?949:(!strcmp(layoutname, "tw")||!strcmp(layoutname, "hk")||!strcmp(layoutname, "zht")||IS_TDOSV?950:(!strcmp(layoutname, "cn")||!strcmp(layoutname, "zh")||!strcmp(layoutname, "zhs")||IS_PDOSV?936:(!strcmp(layoutname, "us")?437:0))));
 #if defined(WIN32)
 		if (dos.loaded_codepage == 932 && !IS_PC98_ARCH && GetKeyboardType(0) == 7 && !strcmp(layoutname, "auto")) layoutname = "jp106";
 #endif
-        if (tocp && stricmp(layoutname, "jp106") && stricmp(layoutname, "jp") && stricmp(layoutname, "ko") && stricmp(layoutname, "cn") && stricmp(layoutname, "hk") && stricmp(layoutname, "tw")) layoutname="us";
+        if (tocp && strcmp(layoutname, "jp106") && strcmp(layoutname, "jp") && strcmp(layoutname, "ko") && strcmp(layoutname, "cn") && strcmp(layoutname, "hk") && strcmp(layoutname, "tw")) layoutname="us";
 
 #if defined(USE_TTF)
         if (TTF_using()) setTTFCodePage(); else
@@ -1702,11 +1702,11 @@ class DOS_KeyboardLayout: public Module_base {
 /*		if (strncmp(layoutname,"auto",4) && strncmp(layoutname,"none",4)) {
 			LOG_MSG("Loading DOS keyboard layout %s ...",layoutname);
 		} */
-        if(!stricmp(layoutname, "cn") || !stricmp(layoutname, "hk") || !stricmp(layoutname, "tw") || !stricmp(layoutname, "ko")) {
+        if(!strcmp(layoutname, "cn") || !strcmp(layoutname, "hk") || !strcmp(layoutname, "tw") || !strcmp(layoutname, "ko")) {
             loaded_layout->read_keyboard_file("us", 437);
-            if(!stricmp(layoutname, "cn")) dos.loaded_codepage = 936;
-            if(!stricmp(layoutname, "hk") || !stricmp(layoutname, "tw")) dos.loaded_codepage = 950;
-            if(!stricmp(layoutname, "ko")) dos.loaded_codepage = 949;
+            if(!strcmp(layoutname, "cn")) dos.loaded_codepage = 936;
+            if(!strcmp(layoutname, "hk") || !strcmp(layoutname, "tw")) dos.loaded_codepage = 950;
+            if(!strcmp(layoutname, "ko")) dos.loaded_codepage = 949;
         }
         if (!tocp && loaded_layout->read_keyboard_file(layoutname, dos.loaded_codepage)) {
             if (strncmp(layoutname,"auto",4)) {
@@ -1720,14 +1720,14 @@ class DOS_KeyboardLayout: public Module_base {
 		}
         if (tocp && !IS_PC98_ARCH) {
             uint16_t cpbak = dos.loaded_codepage;
-            if((dos.loaded_codepage == 932 || tocp == 932) && (!stricmp(layoutname, "jp106") || !stricmp(layoutname, "jp"))) loaded_layout->read_keyboard_file(layoutname, 932);
-            if(!stricmp(layoutname, "ko") || !stricmp(layoutname, "cn") || !stricmp(layoutname, "tw") || !stricmp(layoutname, "hk")) {
+            if((dos.loaded_codepage == 932 || tocp == 932) && (!strcmp(layoutname, "jp106") || !strcmp(layoutname, "jp"))) loaded_layout->read_keyboard_file(layoutname, 932);
+            if(!strcmp(layoutname, "ko") || !strcmp(layoutname, "cn") || !strcmp(layoutname, "tw") || !strcmp(layoutname, "hk")) {
                 loaded_layout->read_keyboard_file("us", 437);
                 dos.loaded_codepage = tocp;
             }
 
             if (!TTF_using() || (TTF_using() && isSupportedCP(tocp))){
-                toSetCodePage(NULL, msgcodepage ? msgcodepage : tocp, -2);
+                toSetCodePage(NULL, msgcodepage ? msgcodepage : tocp, msgcodepage ? -1: -2);
                 runRescan("-A -Q");
 #if C_OPENGL && DOSBOXMENU_TYPE == DOSBOXMENU_SDLDRAW
                 if (OpenGL_using() && control->opt_lang.size() && lastcp && lastcp != dos.loaded_codepage)

From cbecf9eba0f91b0d3c4e27d24508c00c4030164a Mon Sep 17 00:00:00 2001
From: maron2000 <68574602+maron2000@users.noreply.github.com>
Date: Sat, 5 Oct 2024 16:10:12 +0900
Subject: [PATCH 07/10] Fix switching codepage on launch

---
 src/misc/messages.cpp | 23 +++--------------------
 src/misc/programs.cpp |  2 +-
 2 files changed, 4 insertions(+), 21 deletions(-)

diff --git a/src/misc/messages.cpp b/src/misc/messages.cpp
index f92043d62c..b2799e252a 100644
--- a/src/misc/messages.cpp
+++ b/src/misc/messages.cpp
@@ -397,26 +397,9 @@ void LoadMessageFile(const char * fname) {
     menu_update_autocycle();
     update_bindbutton_text();
     dos.loaded_codepage=cp;
-    if (loadlangcp && msgcodepage>0 && isSupportedCP(msgcodepage) && msgcodepage != dos.loaded_codepage) {
-        ShutFontHandle();
-        if(CheckDBCSCP(msgcodepage)) {
-            dos.loaded_codepage = msgcodepage;
-            InitFontHandle();
-            JFONT_Init();
-        }
-        if (!IS_DOSV && !IS_JEGA_ARCH) {
-#if defined(USE_TTF)
-            if (ttf.inUse) toSetCodePage(NULL, msgcodepage, -2); else
-#endif
-            {
-                dos.loaded_codepage = msgcodepage;
-                DOSBox_SetSysMenu();
-#if C_OPENGL && DOSBOXMENU_TYPE == DOSBOXMENU_SDLDRAW
-                if (OpenGL_using() && control->opt_lang.size() && lastcp && lastcp != dos.loaded_codepage)
-                    UpdateSDLDrawTexture();
-#endif
-            }
-            SetKEYBCP();
+    if (loadlangcp && msgcodepage>0) {
+        if(!IS_DOSV && !IS_JEGA_ARCH) {
+            toSetCodePage(NULL, msgcodepage, -1);
         }
     }
     refreshExtChar();
diff --git a/src/misc/programs.cpp b/src/misc/programs.cpp
index b5e4c986d0..df6de1691c 100644
--- a/src/misc/programs.cpp
+++ b/src/misc/programs.cpp
@@ -726,7 +726,7 @@ void dos_ver_menu(bool start), ReloadMapper(Section_prop *sec, bool init), SetGa
 bool set_ver(char *s), GFX_IsFullscreen(void);
 
 void Load_Language(std::string name) {
-    control->opt_lang = name;
+    if(control->opt_lang != "") control->opt_lang = name;
     MSG_Init();
 #if DOSBOXMENU_TYPE == DOSBOXMENU_HMENU || DOSBOXMENU_TYPE == DOSBOXMENU_NSMENU
     mainMenu.unbuild();

From 860f01b985c60807bbaac98857859f248d5d8d79 Mon Sep 17 00:00:00 2001
From: maron2000 <68574602+maron2000@users.noreply.github.com>
Date: Sat, 5 Oct 2024 16:17:12 +0900
Subject: [PATCH 08/10] Always switch codepages for DBCS language files

---
 src/misc/messages.cpp | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/misc/messages.cpp b/src/misc/messages.cpp
index b2799e252a..f1f52d2567 100644
--- a/src/misc/messages.cpp
+++ b/src/misc/messages.cpp
@@ -335,7 +335,7 @@ void LoadMessageFile(const char * fname) {
                         }
                         else {
                             std::string msg = "The specified language file uses code page " + std::to_string(c) + ". Do you want to change to this code page accordingly?";
-                            if(c != dos.loaded_codepage && (control->opt_langcp || uselangcp || !CHCP_changed || !loadlang || (loadlang && systemmessagebox("DOSBox-X language file", msg.c_str(), "yesno", "question", 1)))){
+                            if(c != dos.loaded_codepage && (control->opt_langcp || uselangcp || !CHCP_changed || CheckDBCSCP(c) || !loadlang || (loadlang && systemmessagebox("DOSBox-X language file", msg.c_str(), "yesno", "question", 1)))) {
                                 loadlangcp = true;
                                 msgcodepage = c;
                                 dos.loaded_codepage = c;

From c58d4dc1945d2ec45620d0c4d2f7de458709be9f Mon Sep 17 00:00:00 2001
From: maron2000 <68574602+maron2000@users.noreply.github.com>
Date: Wed, 9 Oct 2024 23:42:36 +0900
Subject: [PATCH 09/10] Fix loading DBCS language files on launch

---
 src/dos/dos_keyboard_layout.cpp | 10 ++++----
 src/misc/messages.cpp           |  6 +++--
 src/shell/shell.cpp             | 41 +++++++++++----------------------
 3 files changed, 23 insertions(+), 34 deletions(-)

diff --git a/src/dos/dos_keyboard_layout.cpp b/src/dos/dos_keyboard_layout.cpp
index c9a362e5e2..18ed7baa1d 100644
--- a/src/dos/dos_keyboard_layout.cpp
+++ b/src/dos/dos_keyboard_layout.cpp
@@ -1142,7 +1142,7 @@ Bitu keyboard_layout::read_codepage_file(const char* codepage_file_name, int32_t
 
 		uint16_t seg=0;
 		uint16_t size=0x1500;
-		if (!DOS_AllocateMemory(&seg,&size)) E_Exit("Not enough free low memory to unpack data");
+        if (!DOS_AllocateMemory(&seg, &size)) E_Exit("Not enough free low memory to unpack data");
 		MEM_BlockWrite(((unsigned int)seg<<4u)+0x100u,cpi_buf,size_of_cpxdata);
 
 		// setup segments
@@ -1704,9 +1704,9 @@ class DOS_KeyboardLayout: public Module_base {
 		} */
         if(!strcmp(layoutname, "cn") || !strcmp(layoutname, "hk") || !strcmp(layoutname, "tw") || !strcmp(layoutname, "ko")) {
             loaded_layout->read_keyboard_file("us", 437);
-            if(!strcmp(layoutname, "cn")) dos.loaded_codepage = 936;
-            if(!strcmp(layoutname, "hk") || !strcmp(layoutname, "tw")) dos.loaded_codepage = 950;
-            if(!strcmp(layoutname, "ko")) dos.loaded_codepage = 949;
+            if(!strcmp(layoutname, "cn")) tocp = 936;
+            if(!strcmp(layoutname, "hk") || !strcmp(layoutname, "tw")) tocp = 950;
+            if(!strcmp(layoutname, "ko")) tocp = 949;
         }
         if (!tocp && loaded_layout->read_keyboard_file(layoutname, dos.loaded_codepage)) {
             if (strncmp(layoutname,"auto",4)) {
@@ -1718,7 +1718,7 @@ class DOS_KeyboardLayout: public Module_base {
 				LOG_MSG("DOS keyboard layout loaded with main language code %s for layout %s",lcode,layoutname);
 			}
 		}
-        if (tocp && !IS_PC98_ARCH) {
+        if ((tocp || msgcodepage) && !IS_PC98_ARCH) {
             uint16_t cpbak = dos.loaded_codepage;
             if((dos.loaded_codepage == 932 || tocp == 932) && (!strcmp(layoutname, "jp106") || !strcmp(layoutname, "jp"))) loaded_layout->read_keyboard_file(layoutname, 932);
             if(!strcmp(layoutname, "ko") || !strcmp(layoutname, "cn") || !strcmp(layoutname, "tw") || !strcmp(layoutname, "hk")) {
diff --git a/src/misc/messages.cpp b/src/misc/messages.cpp
index f1f52d2567..6f9c1557c1 100644
--- a/src/misc/messages.cpp
+++ b/src/misc/messages.cpp
@@ -52,7 +52,9 @@ extern const char * RunningProgram;
 Bitu DOS_ChangeKeyboardLayout(const char* layoutname, int32_t codepage);
 Bitu DOS_ChangeCodepage(int32_t codepage, const char* codepagefile);
 Bitu DOS_LoadKeyboardLayout(const char* layoutname, int32_t codepage, const char* codepagefile);
+const char* DOS_GetLoadedLayout(void);
 bool CheckDBCSCP(int32_t codepage);
+void MSG_Init(void);
 
 #define LINE_IN_MAXLEN 2048
 
@@ -214,7 +216,6 @@ bool CheckDBCSCP(int32_t codepage) {
     else return false;
 }
 
-void MSG_Init(void);
 void SetKEYBCP() {
     if (IS_PC98_ARCH || IS_JEGA_ARCH || IS_DOSV || dos_kernel_disabled || !strcmp(RunningProgram, "LOADLIN")) return;
     Bitu return_code;
@@ -398,7 +399,8 @@ void LoadMessageFile(const char * fname) {
     update_bindbutton_text();
     dos.loaded_codepage=cp;
     if (loadlangcp && msgcodepage>0) {
-        if(!IS_DOSV && !IS_JEGA_ARCH) {
+        const char* layoutname = DOS_GetLoadedLayout();
+        if(!IS_DOSV && !IS_JEGA_ARCH && layoutname != NULL) {
             toSetCodePage(NULL, msgcodepage, -1);
         }
     }
diff --git a/src/shell/shell.cpp b/src/shell/shell.cpp
index eb16b07e72..b09ea77122 100644
--- a/src/shell/shell.cpp
+++ b/src/shell/shell.cpp
@@ -55,7 +55,7 @@ extern bool shell_keyboard_flush;
 extern bool dos_shell_running_program, mountwarning, winautorun;
 extern bool startcmd, startwait, startquiet, internal_program;
 extern bool addovl, addipx, addne2k, enableime, showdbcs;
-extern bool halfwidthkana, force_conversion, gbk;
+extern bool halfwidthkana, force_conversion, gbk, uselangcp;
 extern const char* RunningProgram;
 extern int enablelfn, msgcodepage, lastmsgcp;
 extern uint16_t countryNo;
@@ -80,7 +80,7 @@ void DOS_SetCountry(uint16_t countryNo);
 bool SwitchLanguage(int oldcp, int newcp, bool confirm);
 void CALLBACK_DeAllocate(Bitu in), DOSBox_ConsolePauseWait();
 void GFX_SetTitle(int32_t cycles, int frameskip, Bits timing, bool paused);
-bool isDBCSCP(), InitCodePage(), isKanji1(uint8_t chr), shiftjis_lead_byte(int c), sdl_wait_on_error();
+bool isDBCSCP(), InitCodePage(), isKanji1(uint8_t chr), shiftjis_lead_byte(int c), sdl_wait_on_error(), CheckDBCSCP(int32_t codepage), TTF_using(void);
 
 Bitu call_shellstop = 0;
 /* Larger scope so shell_del autoexec can use it to
@@ -862,34 +862,21 @@ void DOS_Shell::Prepare(void) {
 				if (r!=NULL) *r=0;
 				country = atoi(trim(countrystr));
 				int32_t newCP = r==NULL||IS_PC98_ARCH||IS_JEGA_ARCH||IS_DOSV?dos.loaded_codepage:atoi(trim(r+1));
-                if (control->opt_langcp && msgcodepage>0 && isSupportedCP(msgcodepage) && msgcodepage != newCP)
-                    newCP = msgcodepage;
 				if (r!=NULL) *r=',';
                 if (!IS_PC98_ARCH&&!IS_JEGA_ARCH) {
-#if defined(USE_TTF)
-                    if (ttf.inUse) {
-                        if (newCP) {
-                            int missing = toSetCodePage(this, newCP, control->opt_fastlaunch?1:0);
-                            WriteOut(MSG_Get("SHELL_CMD_CHCP_ACTIVE"), dos.loaded_codepage);
-                            if (missing > 0) WriteOut(MSG_Get("SHELL_CMD_CHCP_MISSING"), missing);
-                        }
-                        else if (r!=NULL) WriteOut(MSG_Get("SHELL_CMD_CHCP_INVALID"), trim(r+1));
-                    } else
-#endif
-                    if (!newCP && IS_DOSV) {
-                        if (IS_JDOSV) newCP=932;
-                        else if (IS_PDOSV) newCP=936;
-                        else if (IS_KDOSV) newCP=949;
-                        else if (IS_TDOSV) newCP=950;
+                    if(!newCP && IS_DOSV) {
+                        if(IS_JDOSV) newCP = 932;
+                        else if(IS_PDOSV) newCP = 936;
+                        else if(IS_KDOSV) newCP = 949;
+                        else if(IS_TDOSV) newCP = 950;
+                    }
+                    if((control->opt_langcp && msgcodepage > 0 ) || CheckDBCSCP(msgcodepage)|| msgcodepage == dos.loaded_codepage) newCP = msgcodepage;
+                    if (newCP != dos.loaded_codepage && (!TTF_using() || (TTF_using() && isSupportedCP(newCP)))) {
+                        int missing = toSetCodePage(this, newCP, control->opt_fastlaunch?1:0);
+                        //WriteOut(MSG_Get("SHELL_CMD_CHCP_ACTIVE"), dos.loaded_codepage);
+                        if (missing > 0) WriteOut(MSG_Get("SHELL_CMD_CHCP_MISSING"), missing);
+                        else if (missing < 0) WriteOut(MSG_Get("SHELL_CMD_CHCP_INVALID"), newCP);
                     }
-                    const char* name = DOS_GetLoadedLayout();
-                    if (newCP==932||newCP==936||newCP==949||newCP==950||newCP==951) {
-                        dos.loaded_codepage=newCP;
-                        SetupDBCSTable();
-                        runRescan("-A -Q");
-                        DOSBox_SetSysMenu();
-                    } else if (control->opt_langcp && !name && (layout.empty() || layout=="auto"))
-                        SetKEYBCP();
                 }
                 //if (lastmsgcp && lastmsgcp != dos.loaded_codepage) SwitchLanguage(lastmsgcp, dos.loaded_codepage, true);
                 if (msgcodepage && msgcodepage != dos.loaded_codepage) SwitchLanguage(dos.loaded_codepage, msgcodepage, true);

From c766244d45ed4de653ca98a83dc2f88c2b79a8ce Mon Sep 17 00:00:00 2001
From: maron2000 <68574602+maron2000@users.noreply.github.com>
Date: Fri, 11 Oct 2024 00:01:29 +0900
Subject: [PATCH 10/10] Fix initial rescan command slow on launch

---
 src/dos/dos_keyboard_layout.cpp |  1 -
 src/misc/messages.cpp           |  5 +++--
 src/shell/shell.cpp             | 20 +++++++++++---------
 src/shell/shell_cmds.cpp        |  4 ++--
 4 files changed, 16 insertions(+), 14 deletions(-)

diff --git a/src/dos/dos_keyboard_layout.cpp b/src/dos/dos_keyboard_layout.cpp
index 18ed7baa1d..05d37e352d 100644
--- a/src/dos/dos_keyboard_layout.cpp
+++ b/src/dos/dos_keyboard_layout.cpp
@@ -1728,7 +1728,6 @@ class DOS_KeyboardLayout: public Module_base {
 
             if (!TTF_using() || (TTF_using() && isSupportedCP(tocp))){
                 toSetCodePage(NULL, msgcodepage ? msgcodepage : tocp, msgcodepage ? -1: -2);
-                runRescan("-A -Q");
 #if C_OPENGL && DOSBOXMENU_TYPE == DOSBOXMENU_SDLDRAW
                 if (OpenGL_using() && control->opt_lang.size() && lastcp && lastcp != dos.loaded_codepage)
                     UpdateSDLDrawTexture();
diff --git a/src/misc/messages.cpp b/src/misc/messages.cpp
index 6f9c1557c1..85a1a06d60 100644
--- a/src/misc/messages.cpp
+++ b/src/misc/messages.cpp
@@ -94,7 +94,7 @@ void MSG_Replace(const char * _name, const char* _val) {
 
 bool InitCodePage() {
     if (!dos.loaded_codepage || dos_kernel_disabled || force_conversion) {
-        if (((control->opt_langcp && msgcodepage != dos.loaded_codepage) || uselangcp) && msgcodepage>0 && isSupportedCP(msgcodepage)) {
+        if (((control->opt_langcp && msgcodepage != dos.loaded_codepage) || uselangcp) && msgcodepage>0) {
             dos.loaded_codepage = msgcodepage;
             return true;
         }
@@ -103,10 +103,11 @@ bool InitCodePage() {
             char *countrystr = (char *)section->Get_string("country"), *r=strchr(countrystr, ',');
             if (r!=NULL && *(r+1)) {
                 int cp = atoi(trim(r+1));
-                if (cp>0 && isSupportedCP(cp)) {
+                if(cp > 0 && isSupportedCP(cp) && !msgcodepage) {
                     dos.loaded_codepage = cp;
                     return true;
                 }
+                else dos.loaded_codepage = msgcodepage;
             }
         }
         if (msgcodepage>0) {
diff --git a/src/shell/shell.cpp b/src/shell/shell.cpp
index b09ea77122..9de39e4edf 100644
--- a/src/shell/shell.cpp
+++ b/src/shell/shell.cpp
@@ -685,7 +685,7 @@ const char *ParseMsg(const char *msg) {
 #if defined(USE_TTF)
         && halfwidthkana
 #endif
-        && InitCodePage() && dos.loaded_codepage==932) uselowbox = true;
+        && dos.loaded_codepage==932) uselowbox = true;
         force_conversion = false;
         dos.loaded_codepage=cp;
         if (uselowbox || IS_JEGA_ARCH || IS_JDOSV) {
@@ -816,6 +816,7 @@ void showWelcome(Program *shell) {
     }
 }
 
+bool finish_prepare = false;
 void DOS_Shell::Prepare(void) {
     if (this == first_shell) {
         Section_prop *section = static_cast<Section_prop *>(control->GetSection("dosbox"));
@@ -872,20 +873,19 @@ void DOS_Shell::Prepare(void) {
                     }
                     if((control->opt_langcp && msgcodepage > 0 ) || CheckDBCSCP(msgcodepage)|| msgcodepage == dos.loaded_codepage) newCP = msgcodepage;
                     if (newCP != dos.loaded_codepage && (!TTF_using() || (TTF_using() && isSupportedCP(newCP)))) {
-                        int missing = toSetCodePage(this, newCP, control->opt_fastlaunch?1:0);
+                        int missing = toSetCodePage(this, newCP, msgcodepage?-1:control->opt_fastlaunch?1:-2);
                         //WriteOut(MSG_Get("SHELL_CMD_CHCP_ACTIVE"), dos.loaded_codepage);
                         if (missing > 0) WriteOut(MSG_Get("SHELL_CMD_CHCP_MISSING"), missing);
                         else if (missing < 0) WriteOut(MSG_Get("SHELL_CMD_CHCP_INVALID"), newCP);
                     }
                 }
-                //if (lastmsgcp && lastmsgcp != dos.loaded_codepage) SwitchLanguage(lastmsgcp, dos.loaded_codepage, true);
-                if (msgcodepage && msgcodepage != dos.loaded_codepage) SwitchLanguage(dos.loaded_codepage, msgcodepage, true);
             }
 			if (country>0&&!control->opt_noconfig) {
 				countryNo = country;
 				DOS_SetCountry(countryNo);
 			}
-			const char * extra = section->data.c_str();
+            runRescan("-A -Q");
+            const char * extra = section->data.c_str();
 			if (extra&&!control->opt_securemode&&!control->SecureMode()&&!control->opt_noconfig) {
 				std::string vstr;
 				std::istringstream in(extra);
@@ -977,10 +977,12 @@ void DOS_Shell::Prepare(void) {
         internal_program = true;
 		VFILE_Register("4DOS.INI",(uint8_t *)i4dos_data,(uint32_t)strlen(i4dos_data), "/4DOS/");
         internal_program = false;
-        unsigned int cp=dos.loaded_codepage;
-        if (!dos.loaded_codepage) InitCodePage();
-        initcodepagefont();
-        dos.loaded_codepage=cp;
+        //unsigned int cp=dos.loaded_codepage;
+        //if (!dos.loaded_codepage) InitCodePage();
+        //initcodepagefont();
+        //dos.loaded_codepage=cp;
+        finish_prepare = true;
+
     }
 #if (defined(WIN32) && !defined(HX_DOS) || defined(LINUX) && C_X11 || defined(MACOSX)) && (defined(C_SDL2) || defined(SDL_DOSBOX_X_SPECIAL))
     if (enableime) SetIMPosition();
diff --git a/src/shell/shell_cmds.cpp b/src/shell/shell_cmds.cpp
index adb98b2f75..b922940131 100644
--- a/src/shell/shell_cmds.cpp
+++ b/src/shell/shell_cmds.cpp
@@ -4526,7 +4526,7 @@ void DOS_Shell::CMD_COUNTRY(char * args) {
 	return;
 }
 
-extern bool jfont_init, isDBCSCP();
+extern bool jfont_init, finish_prepare, isDBCSCP();
 extern Bitu DOS_LoadKeyboardLayout(const char * layoutname, int32_t codepage, const char * codepagefile);
 void runRescan(const char *str), MSG_Init(), JFONT_Init(), InitFontHandle(), ShutFontHandle(), initcodepagefont(), DOSBox_SetSysMenu();
 int toSetCodePage(DOS_Shell *shell, int newCP, int opt) {
@@ -4567,7 +4567,7 @@ int toSetCodePage(DOS_Shell *shell, int newCP, int opt) {
             JFONT_Init();
             SetupDBCSTable();
         }
-        runRescan("-A -Q");
+        if (finish_prepare) runRescan("-A -Q");
 #if defined(USE_TTF)
         if ((opt==-1||opt==-2)&&TTF_using()) {
             Section_prop * ttf_section = static_cast<Section_prop *>(control->GetSection("ttf"));