fix for bug 1517740 (crash in some cases in selection sets)

clang-format

Detect trivial loops

Fix for circular references detection in almost all cases, fixing https://bugs.launchpad.net/inkscape/+bug/167247 and a few of its duplicates. This fix is aimed at preventing any sort of circular references with the URIReference::_acceptObject method, checking the absence of loops in the reference+child tree. There can be some performance improvements done if we add a pointer from cloned sub-objects to their origin sub-object. The remaining cases that are not fixed can involve non-trivial loops using one or more "url()" stylesheet references. Being able to take them into account would require a non-obvious style.cpp refactoring making use of URIReference for this kind of reference (and not handling manually the signals in the styling code, which would probably be a good thing to do anyway)

sp. fix seperate

Code cleanup.

Disconnect before destroying URI

change 0 to NULL for pointers

- fix memleak - fix { } usage - delete NULL is guaranteed to be OK - fix initialization (all paths will eventually init the var, but let the compiler figure that out, instead of a future programmer trying to locate a bug)

Don't try to load JPG and PNG files with createChildDoc().

Slightly improved fix to previous check-in.

Prevent attempt to initialize/compare std::string with/to null pointer.

Check file existance and clean up memory issues thanks to KK and Johan

Move absolute path generator to URI and use std::strings

Improve warnings for missing files. Don't just assert bolocks to the user.

Move sub-document reference creation code from uri-reference to document.cpp as createChildDoc(path)

Protect against infinate looping of new included hrefs

Improve use tag logic by recording the loaded documents in a list.

Add the ability to load external documents in xlink:hrefs such as the use element. See bug #1269880

Finished cleanup of outated SP_OBJECT_DOCUMENT C macro.

Revert recent refactoring changes by johnce because they break the build, which cannot be fixed easily.

SPDocument->Document

whitespace. tab to spaces. improve readability

Applying fixes for gcc 4.3 build issues (closes LP: #169115)

Preserve paint styles with multiple components

fix compiler warning on ordering of init in uri-references.cpp

switch SPStyle to using SPFilterReference for filters; sp_style_new now requires an SPDocument; SPURIReference and SPFilterReference have an alternative constructor taking an owner_document instead of owner object

We were disconnecting the wrong signal, resulting on the old object's release signal lingering after a URIReference's referrent changed. Fixed, thereby fixing bug #1535218.

switch to sigc++ signals for "release"

moving trunk for module inkscape