Have a routine that takes a file name for a personal configuration file

and generates the path name; have it, if the file is to be opened for
reading on Win32, check whether it exists and, if not, check for it in
the old home directory-based configuration directory and, if so, return
that path instead, so that files saved with earlier versions of Ethereal
will be seen.

svn path=/trunk/; revision=4072

4 files changed, 129 insertions, 28 deletions

diff --git a/epan/filesystem.c b/epan/filesystem.c
index 997b1fd816..be2085f891 100644
--- a/epan/filesystem.c
+++ b/epan/filesystem.c
@@ -1,7 +1,7 @@
 /* filesystem.c
  * Filesystem utility routines
  *
- * $Id: filesystem.c,v 1.13 2001/10/24 06:13:05 guy Exp $
+ * $Id: filesystem.c,v 1.14 2001/10/24 07:18:37 guy Exp $
  *
  * Ethereal - Network traffic analyzer
  * By Gerald Combs <gerald@ethereal.com>
@@ -311,7 +311,7 @@ get_systemfile_dir(void)
  * or, if %APPDATA% isn't set, it's "%USERPROFILE%\Application Data"
  * (which is what %APPDATA% normally is on Windows 2000).
  */
-const char *
+static const char *
 get_persconffile_dir(void)
 {
 #ifdef WIN32
@@ -444,3 +444,110 @@ create_persconffile_dir(char **pf_dir_path_return)
 		*pf_dir_path_return = g_strdup(pf_dir_path);
 	return ret;
 }
+
+#ifdef WIN32
+/*
+ * Returns the user's home directory on Win32.
+ */
+static const char *
+get_home_dir(void)
+{
+	static const char *home = NULL;
+	char *homedrive, *homepath;
+	char *homestring;
+	char *lastsep;
+
+	/* Return the cached value, if available */
+	if (home)
+		return home;
+
+	/*
+	 * XXX - should we use USERPROFILE anywhere in this process?
+	 * Is there a chance that it might be set but one or more of
+	 * HOMEDRIVE or HOMEPATH isn't set?
+	 */
+	homedrive = getenv("HOMEDRIVE");
+	if (homedrive != NULL) {
+		homepath = getenv("HOMEPATH");
+		if (homepath != NULL) {
+			/*
+			 * This is cached, so we don't need to worry about
+			 * allocating multiple ones of them.
+			 */
+			homestring =
+			    g_malloc(strlen(homedrive) + strlen(homepath) + 1);
+			strcpy(homestring, homedrive);
+			strcat(homestring, homepath);
+
+			/*
+			 * Trim off any trailing slash or backslash.
+			 */
+			lastsep = find_last_pathname_separator(homestring);
+			if (lastsep != NULL && *(lastsep + 1) == '\0') {
+				/*
+				 * Last separator is the last character
+				 * in the string.  Nuke it.
+				 */
+				*lastsep = '\0';
+			}
+			home = homestring;
+		} else
+			home = homedrive;
+	} else {
+		/*
+		 * Give up and use C:.
+		 */
+		home = "C:";
+	}
+}
+#endif
+
+/*
+ * Construct the path name of a personal configuration file, given the
+ * file name.
+ *
+ * On Win32, if "for_writing" is FALSE, we check whether the file exists
+ * and, if not, construct a path name relative to the ".ethereal"
+ * subdirectory of the user's home directory, and check whether that
+ * exists; if it does, we return that, so that configuration files
+ * from earlier versions can be read.
+ */
+char *
+get_persconffile_path(const char *filename, gboolean for_writing)
+{
+	char *path;
+#ifdef WIN32
+	struct stat s_buf;
+	char *old_path;
+#endif
+
+	path = (gchar *) g_malloc(strlen(get_persconffile_dir()) +
+	    strlen(filename) + 2);
+	sprintf(path, "%s" G_DIR_SEPARATOR_S "%s", get_persconffile_dir(),
+	    filename);
+#ifdef WIN32
+	if (!for_writing) {
+		if (stat(path, &s_buf) != 0 && errno == ENOENT) {
+			/*
+			 * OK, it's not in the personal configuration file
+			 * directory; is it in the ".ethereal" subdirectory
+			 * of their home directory?
+			 */
+			old_path = (gchar *) g_malloc(strlen(get_home_dir()) +
+			    strlen(".ethereal") + strlen(filename) + 3);
+			sprintf(old_path,
+			    "%s" G_DIR_SEPARATOR_S "%s" G_DIR_SEPARATOR ".ethereal",
+			    get_home_dir(), filename);
+			if (stat(old_path, &s_buf) == 0) {
+				/*
+				 * OK, it exists; return it instead.
+				 */
+				g_free(path);
+				path = old_path;
+			}
+		}
+	}
+#endif
+
+	return path;
+}		
diff --git a/epan/filesystem.h b/epan/filesystem.h
index 0e6a2dbbb4..6ad4078473 100644
--- a/epan/filesystem.h
+++ b/epan/filesystem.h
@@ -1,7 +1,7 @@
 /* filesystem.h
  * Filesystem utility definitions
  *
- * $Id: filesystem.h,v 1.9 2001/10/24 06:13:05 guy Exp $
+ * $Id: filesystem.h,v 1.10 2001/10/24 07:18:37 guy Exp $
  *
  * Ethereal - Network traffic analyzer
  * By Gerald Combs <gerald@ethereal.com>
@@ -72,11 +72,6 @@ const char *get_datafile_dir(void);
 const char *get_systemfile_dir(void);
 
 /*
- * Get the directory in which personal configuration files are stored.
- */
-const char *get_persconffile_dir(void);
-
-/*
  * Create the directory that holds personal configuration files, if
  * necessary.  If we attempted to create it, and failed, return -1 and
  * set "*pf_dir_path_return" to the pathname of the directory we failed
@@ -85,4 +80,16 @@ const char *get_persconffile_dir(void);
  */
 int create_persconffile_dir(char **pf_dir_path_return);
 
+/*
+ * Construct the path name of a personal configuration file, given the
+ * file name.
+ *
+ * On Win32, if "for_writing" is FALSE, we check whether the file exists
+ * and, if not, construct a path name relative to the ".ethereal"
+ * subdirectory of the user's home directory, and check whether that
+ * exists; if it does, we return that, so that configuration files
+ * from earlier versions can be read.
+ */
+char *get_persconffile_path(const char *filename, gboolean for_writing);
+
 #endif /* FILESYSTEM_H */
diff --git a/epan/plugins.c b/epan/plugins.c
index f1c8ef2229..69ca623e5a 100644
--- a/epan/plugins.c
+++ b/epan/plugins.c
@@ -1,7 +1,7 @@
 /* plugins.c
  * plugin routines
  *
- * $Id: plugins.c,v 1.36 2001/10/22 22:59:25 guy Exp $
+ * $Id: plugins.c,v 1.37 2001/10/24 07:18:37 guy Exp $
  *
  * Ethereal - Network traffic analyzer
  * By Gerald Combs <gerald@ethereal.com>
@@ -503,12 +503,7 @@ init_plugins(const char *plugin_dir)
 	}
 #endif
 	if (!user_plug_dir)
-	{
-	    user_plug_dir = (gchar *)g_malloc(strlen(get_persconffile_dir()) +
-					      strlen(PLUGINS_DIR_NAME) + 2);
-	    sprintf(user_plug_dir, "%s" G_DIR_SEPARATOR_S "%s",
-		    get_persconffile_dir(), PLUGINS_DIR_NAME);
-	}
+	    user_plug_dir = get_persconffile_path(PLUGINS_DIR_NAME, FALSE);
 	plugins_scan_dir(user_plug_dir);
     }
 }
diff --git a/epan/resolv.c b/epan/resolv.c
index 35861e27f6..287e45bfe3 100644
--- a/epan/resolv.c
+++ b/epan/resolv.c
@@ -1,7 +1,7 @@
 /* resolv.c
  * Routines for network object lookup
  *
- * $Id: resolv.c,v 1.15 2001/10/22 22:59:25 guy Exp $
+ * $Id: resolv.c,v 1.16 2001/10/24 07:18:37 guy Exp $
  *
  * Laurent Deniel <deniel@worldnet.fr>
  *
@@ -637,12 +637,8 @@ static void initialize_ethers(void)
   /* Set g_pethers_path here, but don't actually do anything
    * with it. It's used in get_ethbyname() and get_ethbyaddr()
    */
-  if (g_pethers_path == NULL) {
-    g_pethers_path = g_malloc(strlen(get_persconffile_dir()) +
-			      strlen(ENAME_ETHERS) + 2);
-    sprintf(g_pethers_path, "%s" G_DIR_SEPARATOR_S "%s", 
-	    get_persconffile_dir(), ENAME_ETHERS);
-  }
+  if (g_pethers_path == NULL)
+    g_pethers_path = get_persconffile_path(ENAME_ETHERS, FALSE);
 
   /* manuf hash table initialization */
 
@@ -949,12 +945,8 @@ static void initialize_ipxnets(void)
   /* Set g_pipxnets_path here, but don't actually do anything
    * with it. It's used in get_ipxnetbyname() and get_ipxnetbyaddr()
    */
-  if (g_pipxnets_path == NULL) {
-    g_pipxnets_path = g_malloc(strlen(get_persconffile_dir()) +
-			       strlen(ENAME_IPXNETS) + 2);
-    sprintf(g_pipxnets_path, "%s" G_DIR_SEPARATOR_S "%s", 
-	    get_persconffile_dir(), ENAME_IPXNETS);
-  }
+  if (g_pipxnets_path == NULL)
+    g_pipxnets_path = get_persconffile_path(ENAME_IPXNETS, FALSE);
 
 } /* initialize_ipxnets */