#559 DOS_Shell::CMD_COPY should not copy onto self

[Bruenor41]

if you run command "copy" on file which is source and target then file should not be copied and shell should print message "File cannot be copied onto self". I tested it in dos 5.0 and dos 6.22.

this fixes it (shell_cmds.cpp)
//Special variable to ensure that copy * a_file, where a_file is not a directory concats.
bool special = second_file_of_current_source && target_is_file;
second_file_of_current_source = true;
if (special) oldsource.concat = true;

** if (!oldsource.concat && (!strcasecmp(nameSource, nameTarget))) {
WriteOut("File cannot be copied onto itself\r\n");
dos.dta(save_dta);
DOS_CloseFile(sourceHandle);
if (targetHandle)
DOS_CloseFile(targetHandle);
return;
}**

                //Don't create a new file when in concat mode
                if (oldsource.concat || DOS_CreateFile(nameTarget,0,&targetHandle)) {

[Bruenor41]

Oh, seems I can't modify my ticket... So, sorry for bad layout, I will post it here. Without this fix is target file truncated, result is empty file

        if (DOS_OpenFile(nameSource,0,&sourceHandle)) {
            // Create Target or open it if in concat mode
            strcpy(nameTarget,pathTarget);
            if (nameTarget[strlen(nameTarget)-1]=='\\') strcat(nameTarget,name);

            //Special variable to ensure that copy * a_file, where a_file is not a directory concats.
            bool special = second_file_of_current_source && target_is_file;
            second_file_of_current_source = true; 
            if (special) oldsource.concat = true;

            //FIX
            if (!oldsource.concat && (!strcasecmp(nameSource, nameTarget))) {
                WriteOut("File cannot be copied onto itself\r\n");
                dos.dta(save_dta);
                DOS_CloseFile(sourceHandle);
                if (targetHandle)
                    DOS_CloseFile(targetHandle);
                return;
            }

            //Don't create a new file when in concat mode
            if (oldsource.concat || DOS_CreateFile(nameTarget,0,&targetHandle)) {