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[IMPROVEMENT] Standardize number_bytes upper bound in ts_tables_epg.c#2253

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THE-Amrit-mahto-05 wants to merge 2 commits intoCCExtractor:masterfrom
THE-Amrit-mahto-05:fix/epg-number
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[IMPROVEMENT] Standardize number_bytes upper bound in ts_tables_epg.c#2253
THE-Amrit-mahto-05 wants to merge 2 commits intoCCExtractor:masterfrom
THE-Amrit-mahto-05:fix/epg-number

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@THE-Amrit-mahto-05
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In raising this pull request, I confirm the following (please check boxes):

Reason for this PR:

  • This PR adds new functionality.
  • This PR fixes a bug that I have personally experienced or that a real user has reported and for which a sample exists.
  • This PR is porting code from C to Rust.

Sanity check:

  • I have read and understood the contributors guide.
  • I have checked that another pull request for this purpose does not exist.
  • If the PR adds new functionality, I've added it to the changelog. If it's just a bug fix, I have NOT added it to the changelog.
  • I am NOT adding new C code unless it's to fix an existing, reproducible bug.

Reason

In ts_tables_epg.c, the variable number_bytes had inconsistent upper bounds:

  • One check allowed values < 500
  • Another restricted it to < 200

This inconsistency can lead to unsafe memory handling and unpredictable parsing behavior.

Change

Standardized the upper bound to 200 to match existing validation logic.

Repro instructions

This change improves consistency and safety in bounds checking.
No specific crash case was reproduced, but inconsistent limits were observed in code.

why 200

The value 200 is already used in another validation block in the same file
(compression_type/mode check), so this change ensures consistency and avoids arbitrary limits.

Proof of warning when it was 500:
1
2

after chaning to 200:
solve

@ccextractor-bot
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CCExtractor CI platform finished running the test files on linux. Below is a summary of the test results, when compared to test for commit d56a6be...:
Report Name Tests Passed
Broken 9/13
CEA-708 1/14
DVB 3/7
DVD 3/3
DVR-MS 2/2
General 20/27
Hardsubx 1/1
Hauppage 3/3
MP4 3/3
NoCC 10/10
Options 77/86
Teletext 20/21
WTV 13/13
XDS 31/34

Your PR breaks these cases:

  • ccextractor --autoprogram --out=ttxt --latin1 --ucla --xds 8e8229b88b...
  • ccextractor --autoprogram --out=srt --latin1 --quant 0 85271be4d2...
  • ccextractor --autoprogram --out=ttxt --latin1 132d7df7e9...
  • ccextractor --autoprogram --out=ttxt --latin1 99e5eaafdc...
  • ccextractor --autoprogram --out=srt --latin1 b22260d065...
  • ccextractor --autoprogram --out=ttxt --latin1 --ucla 7aad20907e...
  • ccextractor --autoprogram --out=ttxt --latin1 --ucla dab1c1bd65...
  • ccextractor --autoprogram --out=ttxt --latin1 01509e4d27...
  • ccextractor --out=srt --latin1 --autoprogram 29e5ffd34b...
  • ccextractor --out=spupng c83f765c66...
  • ccextractor --startcreditstext "CCextractor Start crdit Testing" c4dd893cb9...
  • ccextractor --startcreditsnotbefore 1 --startcreditstext "CCextractor Start crdit Testing" c4dd893cb9...
  • ccextractor --startcreditsforatleast 1 --startcreditstext "CCextractor Start crdit Testing" c4dd893cb9...
  • ccextractor --autoprogram --out=ttxt --xds --latin1 --ucla 85058ad37e...
  • ccextractor --autoprogram --out=srt --latin1 --ucla b22260d065...
  • ccextractor --autoprogram --out=ttxt --latin1 --ucla --xds 7f41299cc7...

NOTE: The following tests have been failing on the master branch as well as the PR:

Congratulations: Merging this PR would fix the following tests:

  • ccextractor --startcreditsnotafter 2 --startcreditstext "CCextractor Start crdit Testing" c4dd893cb9..., Last passed: Never
  • ccextractor --startcreditsforatmost 2 --startcreditstext "CCextractor Start crdit Testing" c4dd893cb9..., Last passed: Never

It seems that not all tests were passed completely. This is an indication that the output of some files is not as expected (but might be according to you).

Check the result page for more info.

@ccextractor-bot
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CCExtractor CI platform finished running the test files on windows. Below is a summary of the test results, when compared to test for commit d56a6be...:
Report Name Tests Passed
Broken 9/13
CEA-708 1/14
DVB 4/7
DVD 3/3
DVR-MS 2/2
General 22/27
Hardsubx 1/1
Hauppage 3/3
MP4 3/3
NoCC 10/10
Options 81/86
Teletext 20/21
WTV 13/13
XDS 31/34

Your PR breaks these cases:

  • ccextractor --autoprogram --out=ttxt --latin1 --ucla --xds 8e8229b88b...
  • ccextractor --autoprogram --out=ttxt --latin1 132d7df7e9...
  • ccextractor --autoprogram --out=ttxt --latin1 99e5eaafdc...
  • ccextractor --autoprogram --out=srt --latin1 b22260d065...
  • ccextractor --autoprogram --out=ttxt --latin1 --ucla 7aad20907e...
  • ccextractor --autoprogram --out=ttxt --latin1 01509e4d27...
  • ccextractor --autoprogram --out=ttxt --xds --latin1 --ucla 85058ad37e...
  • ccextractor --autoprogram --out=srt --latin1 --ucla b22260d065...
  • ccextractor --autoprogram --out=ttxt --latin1 --ucla --xds 7f41299cc7...

NOTE: The following tests have been failing on the master branch as well as the PR:

Congratulations: Merging this PR would fix the following tests:

  • ccextractor --autoprogram --out=srt --latin1 --quant 0 85271be4d2..., Last passed: Never
  • ccextractor --autoprogram --out=ttxt --latin1 --ucla dab1c1bd65..., Last passed: Never
  • ccextractor --out=srt --latin1 --autoprogram 29e5ffd34b..., Last passed: Never
  • ccextractor --out=spupng c83f765c66..., Last passed: Never
  • ccextractor --startcreditstext "CCextractor Start crdit Testing" c4dd893cb9..., Last passed: Never
  • ccextractor --startcreditsnotbefore 1 --startcreditstext "CCextractor Start crdit Testing" c4dd893cb9..., Last passed: Never
  • ccextractor --startcreditsnotafter 2 --startcreditstext "CCextractor Start crdit Testing" c4dd893cb9..., Last passed: Never
  • ccextractor --startcreditsforatleast 1 --startcreditstext "CCextractor Start crdit Testing" c4dd893cb9..., Last passed: Never
  • ccextractor --startcreditsforatmost 2 --startcreditstext "CCextractor Start crdit Testing" c4dd893cb9..., Last passed: Never

It seems that not all tests were passed completely. This is an indication that the output of some files is not as expected (but might be according to you).

Check the result page for more info.

@cfsmp3
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cfsmp3 commented Apr 4, 2026

Closing — there's no explanation for why the upper bound should change from 500 to 200. What problem does this solve? What sample triggers an issue with the current 500 limit? Without a repro or justification, we can't merge an arbitrary constant change.

@cfsmp3 cfsmp3 closed this Apr 4, 2026
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3 participants