Mike Kaganski
69ed893087
Commits8f48f91009(ODT export: omit unreferenced <text:list xml:id="...">, 2022-03-10) and82bbf63582(tdf#155823: Improve the check if the list id is not required, 2023-06-14) tried to improve deterministic ODF output, by omitting the list identifiers in case when those identifiers were unreferenced. The latter of these used document model node numbers to check if other lists appeared after the last occurrence of the list that is continuing in the current node. But it turned out, that this isn't robust. Consider this ODF: <text:list xml:id="list1" text:style-name="L1"> <text:list-item> <text:p>a</text:p> </text:list-item> </text:list> <text:p>b<text:note text:id="ftn1" text:note-class="endnote"><text:note-citation>i</text:note-citation><text:note-body> <text:list text:style-name="L2"> <text:list-item> <text:p>x</text:p> </text:list-item> </text:list></text:note-body></text:note></text:p> <text:list text:continue-list="list1" text:style-name="L1"> <text:list-item> <text:p>c</text:p> </text:list-item> </text:list> The paragraphs a, b, and c are all in the main document body, and have sequential document model node numbers (say, 15, 16, 17). If these numbers are checked, there is no node between node 15 ("a") and node 17 ("c") with a different list (both 15 and 17 belong to a list with style "L1" and identifier "list1", and node 16 doesn't belong to any lists). That suggests that the list identifier isn't needed in this case. Bug when the actual output of node 16 is done, it includes a node from an endnote ("x"), which is located in a different place in the document model, and has a node number like 7 (so not between 15 and 17). The paragraph "x" belongs to another list with style "L2", and is output to ODF between paragraphs "a" and "c". Here, we must refer from paragraph "c" to the list of the paragraph "a" using the list id, but this is not obvious when only considering node numbers, and requires the prior knowledge of the actual order of appearance of lists in the ODF. Unless we build a DOM, this is only possible, if we do a two-pass output, and collect the nodes order in the first pass. The output already does that in a "collect autostyles" pass. The problem here is that the "collect autostyles" pass used an optimized function, XMLTextParagraphExport::collectTextAutoStylesOptimized, introduced in commit8195d7061e(INTEGRATION: CWS swautomatic01 (1.126.4); FILE MERGED, 2006-12-01) for #i65476# and which used style::XAutoStylesSupplier for optimization to get the autostyles. This drops XMLTextParagraphExport::collectTextAutoStylesOptimized, and reverts to use of collectTextAutoStyles, which handles nodes in the same order as when writing to ODF. There, we build a vector of the node numbers sequence, used later to sort DocumentListNodes. This uncovered an omission from the work on paragraph mark (commit1a88efa8e0tdf#155238: Reimplement how ListAutoFormat is stored to ODF, 2023-05-11). Turns out, that the code in SwTextFormatter::NewNumberPortion introduced in commitcb0e1b52d6(sw, numbering portion format: consider full-para char formats as well, 2022-10-20) was left behind when re-implementing paragraph marks to use dedicated property; empty trailing spans still affected how the lists were rendered, and that allowed to overlook import defects, where the paragraph mark properties weren't properly set. In ODF import (XMLParaContext::endFastElement), for compatibility, this treats empty trailing spans as defining paragraph mark (when the paragraph mark wasn't set explicitly). This way, the trailing spans get converted to the paragraph mark. In WW8 import, last cell paragraphs didn't call the code handling the paragraph marks. This is also fixed now. The changes result in slightly different numbering of autostyles in the ODF. It seems, that the new numbering more closely follows the order of appearance of the autostyles in the output; and some cases of autostyles that were written, but unreferenced, are now eliminated. The unit tests were updated accordingly. I hope that the performance impact on the export time would not be too large. It is unclear why outline numbering exports a list element at all. Fixing that to not emit the list element is a separate task / TODO. Change-Id: I5c99f8d48be77c4454ffac6ffa9f5babfe0d4909 Reviewed-on: https://gerrit.libreoffice.org/c/core/+/166572 Tested-by: Jenkins Reviewed-by: Mike Kaganski <mike.kaganski@collabora.com>
ODF Import and Export Filter Logic
The main library "xo" contains the basic ODF import/export filter
implementation for most applications. The document is accessed
via its UNO API, which has the advantage that the same import/export
code can be used for text in all applications (from/to Writer/EditEngine).
The filter consumes/produces via SAX UNO API interface (implemented in
"sax"). Various bits of the ODF filters are also implemented in
applications, for example [git:sw/source/filter/xml].
There is a central list of all element or attribute names in
[git:include/xmloff/xmltoken.hxx]. The main class of the import filter
is SvXMLImport, and of the export filter SvXMLExport.
The Import filter maintains a stack of contexts for each element being read. There are many classes specific to particular elements, derived from SvXMLImportContext.
Note that for export several different versions of ODF are supported, with the default being the latest ODF version with "extensions", which means it may contain elements and attributes that are only in drafts of the specification or are not yet submitted for specification. Documents produced in the other (non-extended) ODF modes are supposed to be strictly conforming to the respective specification, i.e., only markup defined by the ODF specification is allowed.
There is another library "xof" built from the source/transform directory, which is the filter for the OpenOffice.org XML format. This legacy format is a predecessor of ODF and was the default in OpenOffice.org 1.x versions, which did not support ODF. This filter works as a SAX transformation from/to ODF, i.e., when importing a document the transform library reads the SAX events from the file and generates SAX events that are then consumed by the ODF import filter.
OpenOffice.org XML File Format
There is some stuff in the "dtd" directory which is most likely related to the OpenOffice.org XML format but is possibly outdated and obsolete.
Add New XML Tokens
When adding a new XML token, you need to add its entry in the following three files:
[git:include/xmloff/xmltoken.hxx][git:xmloff/source/core/xmltoken.cxx][git:xmloff/source/token/tokens.txt]