Do horrible things to support Windows namespace where drive letters are

located speciously designated as "\\?\" but displayed and input as ""
since that's how Windows users think of it.

src/uifc/filepick.c

@@ -161,7 +161,7 @@ char *getdirname(char *path)
 #endif
 	p2 = path;
 	if(p1 > path) {
-		for(p2=p1-1; p2>=path && !IS_PATH_DELIM(*p2); p2--);
+		for(p2=p1-1; p2>path && !IS_PATH_DELIM(*p2); p2--);
 		if(IS_PATH_DELIM(*p2) && *(p2+1))
 			p2++;
 	}
@@ -219,6 +219,8 @@ void display_current_path(uifcapi_t *api, char *path)
 		if(*p=='/')
 			*p='\\';
 	}
+	if (strncmp(dpath, "\\\\?\\", 4)==0)
+		memmove(dpath, dpath+4, strlen(dpath+3));
 #endif
 
 	api->printf(SCRN_LEFT+2, SCRN_TOP+height-2, api->lclr|(api->bclr<<4), "%-*s", width, dpath);
@@ -370,8 +372,18 @@ int filepick(uifcapi_t *api, char *title, struct file_pick *fp, char *dir, char
 		hold_update = TRUE;
 		api->printf(SCRN_LEFT+8, SCRN_TOP+height-3, api->lclr|(api->bclr<<4), "%-*s", width-7, cmsk);
 		tmppath=strdup(cpath);
-		if(tmppath != NULL)
+		if(tmppath != NULL) {
+#ifdef _WIN32
+			if (tmppath[0] == 0 || (tmppath[5]==0 && tmppath[3]=='.' && tmppath[4]=='.' && tmppath[1]==':' && IS_PATH_DELIM(tmppath[2])))
+				strcpy(cpath, "\\\\?\\");
+			else if(strncmp(tmppath, "\\\\?\\", 4)==0 && tmppath[4])
+				strcpy(cpath, tmppath+4);
+			else
+#endif
+			{
 				FULLPATH(cpath,tmppath,sizeof(cpath));
+			}
+		}
 		FREE_AND_NULL(tmppath);
 
 #ifdef __unix__
@@ -399,9 +411,35 @@ int filepick(uifcapi_t *api, char *title, struct file_pick *fp, char *dir, char
 			root=TRUE;
 		else
 			root=FALSE;
-#else
-/* #error Need to do something about root paths (in get_file_opt_list() too!) */
 #endif
+
+#ifdef _WIN32
+		if (strcmp(cpath, "\\\\?\\")==0)
+			root = TRUE;
+		else
+			root = FALSE;
+#endif
+
+#ifdef _WIN32
+		// Hack together some hawtness
+		if (root) {
+			unsigned long drives = _getdrives();
+			int j;
+			char path[4];
+
+			memset(&dgl, 0, sizeof(dgl));
+			strcpy(path, "A:\\");
+			dgl.gl_pathv=malloc(sizeof(char *)*('Z'-'A'+2));
+			for (j=0; j<='Z'-'A'; j++) {
+				if(drives & (1<<j)) {
+					path[0]='A'+j;
+					dgl.gl_pathv[dgl.gl_pathc++]=strdup(path);
+				}
+			}
+		}
+		else 
+#endif
+		{
 			if(glob(dglob, GLOB_MARK, NULL, &dgl)!=0 && !isdir(cpath)) {
 				if(lastpath==NULL) {
 					fp->files=0;
@@ -415,6 +453,7 @@ int filepick(uifcapi_t *api, char *title, struct file_pick *fp, char *dir, char
 				currfield=lastfield;
 				continue;
 			}
+		}
 		if(glob(cglob, 0, NULL, &fgl)!=0)
 			fgl.gl_pathc=0;
 		api->list_height=api->scrn_len-3-7;
@@ -492,25 +531,41 @@ int filepick(uifcapi_t *api, char *title, struct file_pick *fp, char *dir, char
 				case CURRENT_PATH:
 					FREE_AND_NULL(tmplastpath);
 					tmplastpath=strdup(cpath);
+#ifdef _WIN32
+					if (strncmp(tmplastpath, "\\\\?\\", 4)==0)
+						memmove(tmplastpath, tmplastpath+4, strlen(tmplastpath+3));
+					if (strncmp(cfile, "\\\\?\\", 4)==0)
+						memmove(cfile, cfile+4, strlen(cfile+3));
+#endif
 					api->getstrxy(SCRN_LEFT+2, SCRN_TOP+height-2, width-1, cfile, sizeof(cfile)-1, K_EDIT|K_TABEXIT|K_MOUSEEXIT, &i);
 					if(i==ESC) {
 						retval=fp->files=0;
 						goto cleanup;
 					}
 					if((opts & (UIFC_FP_FILEEXIST|UIFC_FP_PATHEXIST)) && !fexist(cfile)) {
+#ifdef _WIN32
+						if (cfile[0])	// Allow zero-length path to mean "Drive list"
+#endif
+						{
 							FREE_AND_NULL(tmplastpath);
 							api->msg("No such path/file!");
 							continue;
 						}
-					if(isdir(cfile))
+					}
+					if(isdir(cfile) && cfile[0])
 						backslash(cfile);
 					_splitpath(cfile, drive, tdir, fname, ext);
 					sprintf(cpath,"%s%s",drive,tdir);
 					if(!isdir(cpath)) {
+#ifdef _WIN32
+						if (cfile[0] && strcmp(cfile, cmsk))	// Allow zero-length path to mean "Drive list"
+#endif
+						{
 							FREE_AND_NULL(tmplastpath);
 							api->msg("No such path!");
 							continue;
 						}
+					}
 					if(i==CIO_KEY_MOUSE)
 						currfield=mousetofield(currfield, opts, height, width, api->list_height, listwidth, &dircur, &dirbar, &filecur, &filebar);
 					if(i==3840)
@@ -522,7 +577,7 @@ int filepick(uifcapi_t *api, char *title, struct file_pick *fp, char *dir, char
 					sprintf(cfile,"%s%s%s%s",drive,tdir,fname,ext);
 					if(strchr(fname,'*') !=NULL || strchr(fname,'?') !=NULL
 						|| strchr(ext,'*') !=NULL || strchr(ext,'?') !=NULL
-						|| (isdir(cfile) && !(opts & UIFC_FP_DIRSEL) && (i=='\r' || i=='\n'))
+						|| ((isdir(cfile) || cfile[0]==0) && !(opts & UIFC_FP_DIRSEL) && (i=='\r' || i=='\n'))
 						|| (!isdir(cfile) && i!='\r' && i!='\n')) {
 						if(opts & UIFC_FP_MSKNOCHG) {
 							sprintf(cfile,"%s%s%s",drive,tdir,cmsk);
@@ -531,7 +586,7 @@ int filepick(uifcapi_t *api, char *title, struct file_pick *fp, char *dir, char
 							continue;
 						}
 						else {
-							if(!isdir(cfile))
+							if((!isdir(cfile)) && cpath[0] != 0)
 								sprintf(cmsk, "%s%s", fname, ext);
 							reread=TRUE;
 						}
@@ -576,7 +631,7 @@ int filepick(uifcapi_t *api, char *title, struct file_pick *fp, char *dir, char
 						}
 					}
 					FREE_AND_NULL(tmplastpath);
-					if((opts & UIFC_FP_MULTI)!=UIFC_FP_MULTI && i!='\t' && i!=3840) {
+					if((opts & UIFC_FP_MULTI)!=UIFC_FP_MULTI && i!='\t' && i!=3840 && cpath[0]) {
 						retval=fp->files=1;
 						fp->selected=(char **)malloc(sizeof(char *));
 						if(fp->selected==NULL) {