Once analysis results for individual files have been generated, these
results need to be combined to make it possible to link from one file
to another. This is the job of the cross-referencer (located in
tools/src/bin/crossref.rs). It reads in target records from every
analysis file and records them in a hashtable. The hashtable maps the
symbol name to every target record with that symbol. Finally, the
hashtable is written to a file ${index}/${tree_name}/crossref. The
general structure is:
{<kind>: [{"path": <file-path>, "lines": [{"lno": <lineno>, "line": <text-of-line>}, ...]}, ...]}
The values for <kind> are Declarations, Definitions, Uses,
Assignments, and IDL. The <text-of-line> contains the text of the
given line, with leading and trailing spaces stripped.
An example entry in this file looks like:
_ZN19nsISupportsPRUint647SetDataEm
{"Declarations":[{"lines":[{"line":"NS_IMETHOD SetData(uint64_t aData) = 0;","lno":830},{"line":"NS_IMETHOD SetData(uint64_t aData) override; \\","lno":842}],"path":"__GENERATED__/dist/include/nsISupportsPrimitives.h"}],"Definitions":[{"lines":[{"line":"nsSupportsPRUint64::SetData(uint64_t aData)","lno":371}],"path":"xpcom/ds/nsSupportsPrimitives.cpp"}],"IDL":[{"lines":[{"line":"attribute uint64_t data;","lno":129}],"path":"xpcom/ds/nsISupportsPrimitives.idl"}],"Uses":[{"lines":[{"line":"wrapper->SetData(mWindowID);","lno":72}],"path":"dom/audiochannel/AudioChannelService.cpp"},{"lines":[{"line":"wrapper->SetData(mID);","lno":8925}],"path":"dom/base/nsGlobalWindow.cpp"},{"lines":[{"line":"ret->SetData(gBrowserTabsRemoteStatus);","lno":1004}],"path":"toolkit/xre/nsAppRunner.cpp"}]}
The first line is the symbol name and the second line is a JSON object describing all the target records for that symbol. The file is not sorted.
In addition, an identifiers file is generated that is used for
id:-style searches. It appears at
${index}/${tree_name}/identifiers. For each target record, the
pretty name of the identifier is broken into components by splitting
on : and .. Given a pretty name of A::B::C, lines are
generated for A::B::C, B::C, and C (since these are the things
people might search on). The line has the form:
<qualified-name-suffix> <symbol-name>
This file is sorted (case insensitively). When the user searches for a
qualified name Abc::Def, the web server will use binary search to
find all lines starting with Abc::Def. Then it looks up the
corresponding symbols in the crossref file and combines those results.
Finally, a jumps file is also generated. This file is used when
generating the "Goto XYZ" context menu items. We only generate one of
these items if there is exactly one definition of a given symbol. For
all such symbols, we generate a line in the jumps file of the
following form:
["<symbol-name>","<definition-path>",<definition-lineno>,"<definition-pretty-name>"]
The pretty name comes from the pretty property of the single target
record for the definition.