Refactor Objects::recover_stream_length #1304
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Make resolve resolve responsible to try again after xref reconstruction rather than returning false to indicate failure. Rename to resolve_all.
Remove invalid objects introduced into the object table during xref table parsing. At the moment, such invalid objects could override valid objects if valid gen < invalid gen. Once the object table is indexed by object id only, the invalid object will prevent valid objects with the same id entering the object table. The additional test case uses good10.pdf, with the dangling reference in the trailer replaced with 3 1 R. Prior to this commit, this caused the page object 3 0 to be masked and replaced with a null object.
Store last used id as a data member. Update when calling next_id / inserting a new object (which only occurs in make_indirect and get_for_json). Add new methods initialize to calculate the initial value for last_id and last_id to query it. Use initialize in QPDF::fixDanglingReferences, which is redundant. Refactor make_indirect to use update_table.
Decompose into new methods update_entry and Entry::update.
Allow for the fact that when processing JSON input we cannot determine whether references are dangling until the whole input has been processed. We handle this by optimistically storing references in the object table. When additional gens are encountered for the same object we store them in the new map unconfirmed_objects. Once processing is complete we clean up the object table and clear unconfirmed_objects. New test cases are adapted from manual-qpdf-json.json etc.
Tests use a modified dangling-bad-xref.pdf.
Use start of next object or xref table to put an upper bound on object length. Tests reuse existing incremental-1.pdf. incremental-1-bad.pdf is incremental-1.pdf with whitespace inserted after object 1 0.
Also, use break to terminate loop in Xref_table::read.
Leave input source correctly positioned to find 'endobj' next.
Codecov ReportAttention: Patch coverage is
Additional details and impacted files@@ Coverage Diff @@
## main #1304 +/- ##
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- Coverage 93.22% 93.19% -0.03%
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Files 308 309 +1
Lines 33795 33933 +138
Branches 4117 4152 +35
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+ Hits 31504 31625 +121
- Misses 2291 2308 +17 ☔ View full report in Codecov by Sentry. |
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Change how the maximum stream length is calculated. For streams not in the xref table, instead of returning 0 length return the maximum length that does not overlap with a known object or xref table.
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Change how the maximum stream length is calculated. For streams not in the xref table, instead of returning 0 length return the maximum length that does not overlap with a known object or xref table. For further detail see #1271.
PR is last 3 commits only, remainder is #1302 and earlier.