Improve MANPATH control

* Revert changes to programs/dtsearchpath/libCliSrv/UnixEnv.C
  introduced by c3cb5b8aa6
  that could have produced disappearing Application Manager
  icons on FreeBSD
* Introduce SearchPath:useSystemPath() virtual method to tell
  dtsearchpath to leave some environment variables alone.

  It is currently overriden for FreeBSD only if the MANPATH
  is empty (system default). Other operating systems
  might want to override it if they prefer to have distribution
  specific control of a search path in effect.

* Symlink /usr/dt/share/man to /usr/dt/man for FreeBSD
  This allows dtsearchpath to actually include /usr/dt/man
  in the MANPATH when MANPATH override is in effect.

cde/databases/CDE-MAN.udb

@@ -1288,6 +1288,10 @@ doc/C/man/man4/mwmrc.4
 	install_target = /usr/dt/man
 	type = sym_link
 }
+{ freebsd
+	install_target = /usr/dt/man
+	type = sym_link
+}
 #
 ./share/catman
 { uxp

cde/programs/dtsearchpath/dtsp/ManSearchPath.C

@@ -42,12 +42,6 @@ ManSearchPath::ManSearchPath
 	const char *     sep
 	) : SearchPath(user, envvar, sep)
 {
-#if defined(__FreeBSD__)
-    /* Installer on FreeBSD sets up man configuration so that
-     * setting MANPATH is not necessary
-     */
-    if (!user->OS()->MANPATH().isNull()) {
-#endif
     if (user->DTMANPATH())
 	search_path = user->FactoryManPath() + "," + *user->DTMANPATH();
     else
@@ -61,9 +55,6 @@ ManSearchPath::ManSearchPath
 
     NormalizePath();
     TraversePath();
-#if defined(__FreeBSD__)
-    }
-#endif
 }
 
 
@@ -97,6 +88,22 @@ void ManSearchPath::MakePath
     }
 }
 
+#if defined(__FreeBSD__)
+/*****************************************************************
+ *  useSystemPath()
+ *
+ *         Check whether to leave MANPATH unmodified (or unset)
+ *
+ */
+int ManSearchPath::useSystemPath()
+{
+     if (user->OS()->getEnvironmentVariable("MANPATH").isNull()) {
+       return 1;
+     } else {
+       return 0;
+     }
+}
+#endif
 
 /*****************************************************************
  *  ExportPath()
@@ -106,9 +113,11 @@ void ManSearchPath::MakePath
  *****************************************************************/
 void ManSearchPath::ExportPath()
 {
-    CString env(GetEnvVar());
-    user->OS()->shell()->putToEnv(env,
+    if (!useSystemPath()) {
+      CString env(GetEnvVar());
+      user->OS()->shell()->putToEnv(env,
 		       final_search_path.data());
+    }
 }
 
 
@@ -116,7 +125,7 @@ void ManSearchPath::Print()
 {
     printf("%s:\n", GetEnvVar());
     CString sp(GetSearchPath());
-    if (!sp.isNull()) {
+    if (!useSystemPath() && !sp.isNull()) {
 	CTokenizedString path (sp,Separator().data());
 	CString subpath = path.next();
 	while (!subpath.isNull()) {

cde/programs/dtsearchpath/dtsp/SearchPath.C

@@ -329,6 +329,19 @@ int SearchPath::validSearchPath
     return 0;
 }
 
+/*********************************************************************
+ *  useSystemPath()
+ *
+ *    This member function verifies whether system environment variable
+ *    should be left unmodified, since some other configuraton mechanism
+ *    is in effect.
+ *
+ */
+int SearchPath::useSystemPath()
+{
+    return 0;
+}
+
 /*****************************************************************
  *  ExportPath()
  *
@@ -340,7 +353,9 @@ void SearchPath::ExportPath()
     CString env(environment_var);
     env += "SEARCHPATH";
 
-    user->OS()->shell()->putToEnv(env, final_search_path.data());
+    if (!useSystemPath()) {
+      user->OS()->shell()->putToEnv(env, final_search_path.data());
+    }
 }
 
 
@@ -354,7 +369,7 @@ void SearchPath::Print()
 {
     printf("%sSEARCHPATH:\n", GetEnvVar());
     CString sp(GetSearchPath());
-    if (!sp.isNull()) {
+    if (!useSystemPath() && !sp.isNull()) {
 	CTokenizedString path (sp,Separator().data());
 	CString subpath = path.next();
 	while (!subpath.isNull()) {

cde/programs/dtsearchpath/dtsp/SearchPath.h

@@ -78,6 +78,7 @@ class SearchPath {
   CString Separator() const    { return separator; }
 
   virtual int validSearchPath (const CString &) const;
+  virtual int useSystemPath();
 
   void    setSeparator (const char * sep) { separator = sep; }
 
@@ -193,6 +194,9 @@ class ManSearchPath : public SearchPath {
 
  protected:
   virtual void    MakePath (const CString &);
+#if defined(__FreeBSD__)
+  virtual int     useSystemPath();
+#endif
 
  private:
 };

cde/programs/dtsearchpath/libCliSrv/UnixEnv.C

@@ -83,7 +83,7 @@ UnixEnvironment::UnixEnvironment()
 #elif defined(__OpenBSD__)
 	manpath = "/usr/share/man:/usr/X11R6/man:/usr/local/man:/usr/ports/infrastructure/man";
 #elif defined(__FreeBSD__)
-	manpath = temp;
+	manpath = "/usr/share/man:/usr/local/man";
 #endif
     else
 	manpath = temp;