Improve compliance when printing drive labels

include/drives.h

@@ -30,6 +30,7 @@
 
 bool WildFileCmp(const char * file, const char * wild);
 void Set_Label(char const * const input, char * const output, bool cdrom);
+std::string To_Label(const char* name);
 
 class DriveManager {
 public:

include/support.h

@@ -93,5 +93,7 @@ Bits ConvHexWord(char * word);
 void trim(std::string& str);
 void upcase(std::string &str);
 void lowcase(std::string &str);
+void strip_punctuation(std::string &str);
+
 
 #endif

src/dos/dos_programs.cpp

@@ -144,16 +144,13 @@ public:
 			if (ret) {
 				dta.GetResult(name,size,date,time,attr);
 				DOS_FindNext(); //Mark entry as invalid
-			} else name[0] = 0;
-
-			/* Change 8.3 to 11.0 */
-			char* dot = strchr(name,'.');
-			if(dot && (dot - name == 8) ) {
-				name[8] = name[9];name[9] = name[10];name[10] = name[11];name[11] = 0;
+			} else {
+				name[0] = 0;
 			}
-
+			std::string label = To_Label(name);
 			root[1] = 0; //This way, the format string can be reused.
-			WriteOut(MSG_Get("PROGRAM_MOUNT_STATUS_FORMAT"),root, Drives[d]->GetInfo(),name);
+			WriteOut(MSG_Get("PROGRAM_MOUNT_STATUS_FORMAT"),
+			                 root, Drives[d]->GetInfo(), label.c_str());
 		}
 		dos.dta(save_dta);
 	}

src/dos/drives.cpp

@@ -73,6 +73,19 @@ checkext:
 	return true;
 }
 
+
+std::string To_Label(const char* name) {
+	// Reformat the name per the DOS label specification:
+	// - Upper-case, up to 11 ASCII characters
+	// - Internal spaces allowed but no: tabs ? / \ | . , ; : + = [ ] < > " '
+	std::string label(name);
+	trim(label); // strip front-and-back white-space
+	strip_punctuation(label); // strip all punctuation
+	label.resize(11); // collapse remainder to (at-most) 11 chars
+	upcase(label);
+	return label;
+}
+
 void Set_Label(char const * const input, char * const output, bool cdrom) {
 	Bitu togo     = 8;
 	Bitu vnamePos = 0;

src/misc/support.cpp

@@ -21,6 +21,7 @@
 #include <assert.h>
 #include <cctype>
 #include <ctype.h>
+#include <functional>
 #include <stdarg.h>
 #include <stdio.h>
 #include <stdlib.h>
@@ -51,6 +52,15 @@ void trim(std::string &str) {
 	if (loc != std::string::npos) str.erase(loc+1);
 }
 
+void strip_punctuation(std::string &str) {
+	str.erase(
+		std::remove_if(
+			str.begin(),
+			str.end(),
+			[](unsigned char c){ return std::ispunct(c); }),
+		str.end());
+}
+
 /* 
 	Ripped some source from freedos for this one.