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Public Member Functions | Static Public Member Functions | Protected Member Functions | Protected Attributes
DiffState Class Reference
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List of all members.

Public Member Functions

 Config ($state, $flags=0)
 Initializes the state.
 GetState ()
 Returns state.

Static Public Member Functions

static RowCmp ($a, $b)
 
DiffState specific stuff

Protected Member Functions

 getDiffTo ($new)
 Differential mechanism Compares the current syncstate to the sent $new.
 updateState ($type, $change)
 Update the state to reflect changes.
 isConflict ($type, $folderid, $id)
 Returns TRUE if the given ID conflicts with the given operation.

Protected Attributes

 $syncstate
 $backend
 $flags

Detailed Description

Definition at line 51 of file diffstate.php.


Member Function Documentation

DiffState::Config ( state,
flags = 0 
)

Initializes the state.

Parameters:
string$state
int$flagspublic
Returns:
boolean status flag
Exceptions:
StatusException

Implements IChanges.

Definition at line 66 of file diffstate.php.

                                               {
        if ($state == "")
            $state = array();

        if (!is_array($state))
            throw new StatusException("Invalid state", SYNC_FSSTATUS_CODEUNKNOWN);

        $this->syncstate = $state;
        $this->flags = $flags;
        return true;
    }
DiffState::getDiffTo ( new) [protected]

Differential mechanism Compares the current syncstate to the sent $new.

Parameters:
array$newprotected
Returns:
array

Definition at line 120 of file diffstate.php.

                                       {
        $changes = array();

        // Sort both arrays in the same way by ID
        usort($this->syncstate, array("DiffState", "RowCmp"));
        usort($new, array("DiffState", "RowCmp"));

        $inew = 0;
        $iold = 0;

        // Get changes by comparing our list of messages with
        // our previous state
        while(1) {
            $change = array();

            if($iold >= count($this->syncstate) || $inew >= count($new))
                break;

            if($this->syncstate[$iold]["id"] == $new[$inew]["id"]) {
                // Both messages are still available, compare flags and mod
                if(isset($this->syncstate[$iold]["flags"]) && isset($new[$inew]["flags"]) && $this->syncstate[$iold]["flags"] != $new[$inew]["flags"]) {
                    // Flags changed
                    $change["type"] = "flags";
                    $change["id"] = $new[$inew]["id"];
                    $change["flags"] = $new[$inew]["flags"];
                    $changes[] = $change;
                }

                if($this->syncstate[$iold]["mod"] != $new[$inew]["mod"]) {
                    $change["type"] = "change";
                    $change["id"] = $new[$inew]["id"];
                    $changes[] = $change;
                }

                $inew++;
                $iold++;
            } else {
                if($this->syncstate[$iold]["id"] > $new[$inew]["id"]) {
                    // Message in state seems to have disappeared (delete)
                    $change["type"] = "delete";
                    $change["id"] = $this->syncstate[$iold]["id"];
                    $changes[] = $change;
                    $iold++;
                } else {
                    // Message in new seems to be new (add)
                    $change["type"] = "change";
                    $change["flags"] = SYNC_NEWMESSAGE;
                    $change["id"] = $new[$inew]["id"];
                    $changes[] = $change;
                    $inew++;
                }
            }
        }

        while($iold < count($this->syncstate)) {
            // All data left in 'syncstate' have been deleted
            $change["type"] = "delete";
            $change["id"] = $this->syncstate[$iold]["id"];
            $changes[] = $change;
            $iold++;
        }

        while($inew < count($new)) {
            // All data left in new have been added
            $change["type"] = "change";
            $change["flags"] = SYNC_NEWMESSAGE;
            $change["id"] = $new[$inew]["id"];
            $changes[] = $change;
            $inew++;
        }

        return $changes;
    }

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Returns state.

public

Returns:
string
Exceptions:
StatusException

Implements IChanges.

Definition at line 85 of file diffstate.php.

                               {
        if (!isset($this->syncstate) || !is_array($this->syncstate))
            throw new StatusException("DiffState->GetState(): Error, state not available", SYNC_FSSTATUS_CODEUNKNOWN, null, LOGLEVEL_WARN);

        return $this->syncstate;
    }
DiffState::isConflict ( type,
folderid,
id 
) [protected]

Returns TRUE if the given ID conflicts with the given operation.

This is only true in the following situations:

  • Changed here and changed there
  • Changed here and deleted there
  • Deleted here and changed there Any other combination of operations can be done (e.g. change flags & move or move & delete)
Parameters:
string$typeof change
string$folderid
string$idprotected
Returns:

Definition at line 246 of file diffstate.php.

                                                         {
        $stat = $this->backend->StatMessage($folderid, $id);

        if(!$stat) {
            // Message is gone
            if($type == "change")
                return true; // deleted here, but changed there
            else
                return false; // all other remote changes still result in a delete (no conflict)
        }

        foreach($this->syncstate as $state) {
            if($state["id"] == $id) {
                $oldstat = $state;
                break;
            }
        }

        if(!isset($oldstat)) {
            // New message, can never conflict
            return false;
        }

        if($stat["mod"] != $oldstat["mod"]) {
            // Changed here
            if($type == "delete" || $type == "change")
                return true; // changed here, but deleted there -> conflict, or changed here and changed there -> conflict
            else
                return false; // changed here, and other remote changes (move or flags)
        }
    }

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static DiffState::RowCmp ( a,
b 
) [static]


DiffState specific stuff

Comparing function used for sorting of the differential engine

Parameters:
array$a
array$bpublic
Returns:
boolean

Definition at line 106 of file diffstate.php.

                                          {
        // TODO implement different comparing functions
        return $a["id"] < $b["id"] ? 1 : -1;
    }
DiffState::updateState ( type,
change 
) [protected]

Update the state to reflect changes.

Parameters:
string$typeof change
array$changeprotected
Returns:

Definition at line 204 of file diffstate.php.

                                                   {
        // Change can be a change or an add
        if($type == "change") {
            for($i=0; $i < count($this->syncstate); $i++) {
                if($this->syncstate[$i]["id"] == $change["id"]) {
                    $this->syncstate[$i] = $change;
                    return;
                }
            }
            // Not found, add as new
            $this->syncstate[] = $change;
        } else {
            for($i=0; $i < count($this->syncstate); $i++) {
                // Search for the entry for this item
                if($this->syncstate[$i]["id"] == $change["id"]) {
                    if($type == "flags") {
                        // Update flags
                        $this->syncstate[$i]["flags"] = $change["flags"];
                    } else if($type == "delete") {
                        // Delete item
                        array_splice($this->syncstate, $i, 1);
                    }
                    return;
                }
            }
        }
    }

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Member Data Documentation

DiffState::$backend [protected]

Definition at line 53 of file diffstate.php.

DiffState::$flags [protected]

Definition at line 54 of file diffstate.php.

DiffState::$syncstate [protected]

Definition at line 52 of file diffstate.php.


The documentation for this class was generated from the following file: