From 903b990a10d86f0f848d6227d60ebc4859782792 Mon Sep 17 00:00:00 2001
From: Holger Vogt <holger.vogt@uni-due.de>
Date: Sun, 11 Aug 2019 09:45:46 +0200
Subject: [PATCH] separate handling of tilde expansion: MS Windows MINGW and
 VC++ versus all the others

---
 src/misc/tilde.c | 89 +++++++++++++++++++++++++-----------------------
 1 file changed, 47 insertions(+), 42 deletions(-)

diff --git a/src/misc/tilde.c b/src/misc/tilde.c
index db0ef8bd4..3da407501 100644
--- a/src/misc/tilde.c
+++ b/src/misc/tilde.c
@@ -14,45 +14,61 @@ Modified: 2002 R. Oktas, <roktas@omu.edu.tr>
 #if defined(__MINGW32__) || defined(_MSC_VER)
 #undef BOOLEAN
 #include <windows.h> /* win32 functions */
-#include "shlobj.h"  /* SHGetFolderPath */
+#include <shlobj.h>  /* SHGetFolderPath */
 #endif
 
-/* XXX To prevent a name collision with `readline's `tilde_expand',
-   the original name: `tilde_expand' has changed to `tildexpand'. This
-   situation naturally brings to mind that `tilde_expand' could be used
-   directly from `readline' (since it will already be included if we
-   wish to activate the `readline' support). Following implementation of
-   'tilde expanding' has some problems which constitutes another good
-   reason why it should be replaced: eg. it returns NULL which should
-   not behave this way, IMHO.  Anyway... Don't care for the moment, may
-   be in the future. -- ro */
-
-
+/* For Windows MINGW and Visual Studio: Expand the tilde '~' to the
+   environmental variable HOME, if set by the user. If not set, it
+   expands to the env variable USERPROFILE, that typically returns
+   C:\Users\<user name>. If this is not available, a folder path led
+   to by CSIDL_PERSONAL, i.e.  C:\Users\<user name>\Documents.
+   If not MINGW or Visual Studio, and if  HAVE_PWD_H is defined,
+   then '~' is expanded to HOME, else string is returned.
+*/
 char *
 tildexpand(char *string)
 {
-#ifdef HAVE_PWD_H
-    char buf[BSIZE_SP];
-    char *k, c;
-#endif
-#if defined(__MINGW32__) || defined(_MSC_VER)
-    char buf2[BSIZE_SP];
-#endif
     char *result = NULL;
 
     if (!string)
-	return NULL;
+        return NULL;
 
     string = skip_ws(string);
 
     if (*string != '~')
         return copy(string);
 
+#if defined(__MINGW32__) || defined(_MSC_VER)
+    char buf2[BSIZE_SP];
+    string += 1;
+    result = getenv("HOME");
+    if (!result)
+        result = getenv("USERPROFILE");
+    if (!result)
+        if (SUCCEEDED(SHGetFolderPath(NULL, CSIDL_PERSONAL, NULL, 0, buf2))) {
+            if (*string)
+                strcat(buf2, string);
+            return copy(buf2);
+        }
+        else
+            return NULL;
+    else {
+        strcpy(buf2, result);
+        if (*string)
+            strcat(buf2, string);
+        return copy(buf2);
+    }
+#else
+
+#ifdef HAVE_PWD_H
+    char buf[BSIZE_SP];
+    char *k, c;
+#endif
+
     string += 1;
 
     if (!*string || *string == '/') {
-       /* First try the environment setting. May also make life easier
-          for non-unix platforms, eg. MS-DOS. -- ro */
+       /* First try the environment setting. */
        result = getenv("HOME");
 #ifdef HAVE_PWD_H
        /* Can't find a result from the environment, let's try
@@ -78,31 +94,20 @@ tildexpand(char *string)
     }
     if (result) {
 #ifdef HAVE_PWD_H
-       strcpy(buf, result);
-	if (*string)
-	    strcat(buf, string);
-	return copy(buf);
-
+        strcpy(buf, result);
+        if (*string)
+            strcat(buf, string);
+        return copy(buf);
     } else
-	return NULL;
+        return NULL;
 
 #else
-       /* Emulate the old behavior to prevent side effects. -- ro */
-       return copy(string);
+        /* Emulate the old behavior to prevent side effects. -- ro */
+        return copy(string);
     }
-#if defined(__MINGW32__) || defined(_MSC_VER)
-    else if(SUCCEEDED(SHGetFolderPath(NULL,
-                             CSIDL_PERSONAL,
-                             NULL,
-                             0,
-                             buf2)))
-    {
-        if (*string)
-            strcat(buf2, string);
-        return copy(buf2);
-    }
-#endif
+
     return NULL;
 #endif
+#endif
 }