Fix data corruption from unrecognized entity in StrPair::GetStr() (#1082)#1086
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Fix data corruption from unrecognized entity in StrPair::GetStr() (#1082)#1086steps-re wants to merge 1 commit into
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When an unrecognized entity (e.g. &bogus;) follows a recognized entity that was expanded to a shorter string, the write pointer q lags behind the read pointer p. The unrecognized-entity branch advanced both pointers without writing *q, so a stale buffer byte replaced the '&' in the output (e.g. "&&bogus;" parsed to "&abogus;" instead of "&&bogus;"). Copy *p to *q before advancing, matching the numeric character-reference fallback a few lines above. Adds a focused xmltest assertion. Fixes leethomason#1082. Signed-off-by: Mike German <mike@stepsventures.com>
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Fixes #1082.
Bug
In
StrPair::GetStr(), values are un-escaped in place with a read pointerpand a write pointerq. After a recognized entity like&expands, output is shorter than input, soqtrailsp. The unrecognized-entity branch then advanced both pointers (++p; ++q;) without writing*q, so a stale earlier byte replaced the&. An unknown entity's&was silently corrupted:Fix
Write
*q = *p;before advancing in the unrecognized-entity branch — identical to the numeric-character-reference fallback a few lines above. Correctly preserves the&in theq == pcase too.Verification
&abogus;before, correct&&bogus;after.xmltest.cppnext to the existing entity-transformation tests: fails on unfixed code (Pass 529, Fail 1), passes with the fix.xmltest: 530/530 pass, no regressions.