add delaymount option which delays initial mount. Patch by Jeff King

git-svn-id: http://encfs.googlecode.com/svn/trunk@115 db9cf616-1c43-0410-9cb8-a902689de0d6

encfs/encfs.pod

@@ -10,7 +10,7 @@ B<encfs> [B<--version>] [B<-s>] [B<-f>] [B<-v>|B<--verbose>]
 [B<-i MINUTES>|B<--idle=MINUTES>] [B<--extpass=program>] 
 [B<-S>|B<--stdinpass>] [B<--anykey>] [B<--forcedecode>] 
 [B<-d>|B<--fuse-debug>] [B<--public>] [B<--no-default-flags>]
-[B<--ondemand>] [B<--reverse>] [B<--standard>] 
+[B<--ondemand>] [B<--delaymount>] [B<--reverse>] [B<--standard>] 
 [B<-o FUSE_OPTION>]
 I<rootdir> I<mountPoint> 
 [B<--> [I<Fuse Mount Options>]]
@@ -106,6 +106,11 @@ internally dropping its reference to it.  If someone attempts to access the
 filesystem again, the extpass program is used to prompt the user for the
 password.  If this succeeds, then the filesystem becomes available again.
 
+=item B<--delaymount>
+
+Do not mount the filesystem when encfs starts; instead, delay mounting until
+first use.  This option only makes sense with B<--ondemand>.
+
 =item B<--reverse>
 
 Normally B<EncFS> provides a plaintext view of data on demand.  Normally it

encfs/main.cpp

@@ -102,6 +102,7 @@ struct EncFS_Args
     if(opts->annotate) ss << "(annotate) ";
     if(opts->reverseEncryption) ss << "(reverseEncryption) ";
     if(opts->mountOnDemand) ss << "(mountOnDemand) ";
+    if(opts->delayMount) ss << "(delayMount) ";
     for(int i=0; i<fuseArgc; ++i)
       ss << fuseArgv[i] << ' ';
 
@@ -219,6 +220,7 @@ bool processArgs(int argc, char *argv[], const shared_ptr<EncFS_Args> &out)
     {"anykey", 0, 0, 'k'}, // skip key checks
     {"no-default-flags", 0, 0, 'N'}, // don't use default fuse flags
     {"ondemand", 0, 0, 'm'}, // mount on-demand
+    {"delaymount", 0, 0, 'M'}, // delay initial mount until use
     {"public", 0, 0, 'P'}, // public mode
     {"extpass", 1, 0, 'p'}, // external password program
     // {"single-thread", 0, 0, 's'}, // single-threaded mode
@@ -294,6 +296,9 @@ bool processArgs(int argc, char *argv[], const shared_ptr<EncFS_Args> &out)
     case 'm':
       out->opts->mountOnDemand = true;
       break;
+    case 'M':
+      out->opts->delayMount = true;
+      break;
     case 'N':
       useDefaultFlags = false;
       break;
@@ -404,6 +409,15 @@ bool processArgs(int argc, char *argv[], const shared_ptr<EncFS_Args> &out)
     }
   }
 
+  if(out->opts->delayMount && !out->opts->mountOnDemand)
+  {
+    cerr <<
+      // xgroup(usage)
+      _("You must use mount-on-demand with delay-mount")
+      << endl;
+    return false;
+  }
+
   if(out->opts->mountOnDemand && out->opts->passwordProgram.empty())
   {
     cerr << 
@@ -594,6 +608,10 @@ int main(int argc, char *argv[])
 
   if( rootInfo )
   {
+    // turn off delayMount, as our prior call to initFS has already
+    // respected any delay, and we want future calls to actually mount.
+    encfsArgs->opts->delayMount = false;
+
     // set the globally visible root directory node
     ctx->setRoot( rootInfo->root );
     ctx->args = encfsArgs;

fs/FileUtils.cpp

@@ -1609,6 +1609,14 @@ RootPtr initFS( EncFS_Context *ctx, const shared_ptr<EncFS_Opts> &opts )
       return rootInfo;
     }
 
+    if(opts->delayMount)
+    {
+      rootInfo = RootPtr( new EncFS_Root );
+      rootInfo->cipher = cipher;
+      rootInfo->root = shared_ptr<DirNode>();
+      return rootInfo;
+    }
+
     // get user key
     CipherKey userKey;
 

fs/FileUtils.h

@@ -72,6 +72,7 @@ struct EncFS_Opts
   bool createIfNotFound;  // create filesystem if not found
   bool idleTracking; // turn on idle monitoring of filesystem
   bool mountOnDemand; // mounting on-demand
+  bool delayMount;    // delay initial mount
 
   bool checkKey;  // check crypto key decoding
   bool forceDecode; // force decode on MAC block failures
@@ -91,6 +92,7 @@ struct EncFS_Opts
     createIfNotFound = true;
     idleTracking = false;
     mountOnDemand = false;
+    delayMount = false;
     checkKey = true;
     forceDecode = false;
     useStdin = false;