FIX: Flush pending EIT sections in EPG_free() before freeing buffers

[Varadraj75]

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Summary

Fixes #2165 — the last EIT section in any stream was silently discarded.

Root Cause

parse_EPG_packet() accumulates TS packets into epg_buffers[] and only
calls EPG_parse_table() when a new section starts (payload_start_indicator=1).
This means the last accumulated section is never parsed — there is no
following packet to trigger the flush.

EPG_free() then freed the buffers without processing them, silently
discarding the last EIT section in every stream.

Fix

EPG_free() now iterates over all epg_buffers slots before freeing and
flushes any with ccounter > 0:

// Flush any pending EIT sections not triggered by a subsequent
// payload_start_indicator packet (e.g. last section in stream)
for (int i = 0; i <= 0xfff; i++)
{
    if (ctx->epg_buffers[i].buffer != NULL && ctx->epg_buffers[i].ccounter > 0)
    {
        EPG_parse_table(ctx, ctx->epg_buffers[i].buffer, ctx->epg_buffers[i].buffer_length);
        free(ctx->epg_buffers[i].buffer);
        ctx->epg_buffers[i].buffer = NULL;
    }
}

Impact

• Fixes missing EPG/XMLTV data for the last program entry in streams
• Particularly impactful for short streams or streams with few EIT sections
  where the last section represents a significant portion of the EPG data

Testing

Built and verified locally on macOS. All existing CI tests pass.

Fixes #2165

[Copilot]

Pull request overview

This PR fixes a long-standing Transport Stream EPG edge case where the final accumulated EIT/PSI section was never parsed because parsing was only triggered when a new section started, causing the last section in the stream to be silently dropped.

Changes:

• Flush any pending EIT sections from epg_buffers[] during EPG_free() before freeing EPG state.
• Document the fix in the changelog (references #2165).

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 1 comment.

File	Description
src/lib_ccx/ts_tables_epg.c	Flushes buffered (previously unflushed) EIT sections during cleanup to avoid losing the final section.
docs/CHANGES.TXT	Adds a changelog entry describing the fix and linking to the reported issue.

---

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[Copilot]

Before calling EPG_parse_table() here, please validate that the pending buffer is large enough (e.g., buffer_length > 0 and pointer_field+1 < buffer_length) to avoid out-of-bounds reads when the last buffered section is truncated/malformed or when payload_length ended up as 0. This flush path can now parse buffers that previously would have been dropped at shutdown, so it should be resilient to incomplete data.

Suggested change

	EPG_parse_table(ctx, ctx->epg_buffers[i].buffer, ctx->epg_buffers[i].buffer_length);
	// Validate buffer before parsing to avoid out-of-bounds reads
	if (ctx->epg_buffers[i].buffer_length > 0)
	{
	unsigned char pointer_field = (unsigned char)ctx->epg_buffers[i].buffer[0];
	if ((size_t)pointer_field + 1 < (size_t)ctx->epg_buffers[i].buffer_length)
	{
	EPG_parse_table(ctx,
	ctx->epg_buffers[i].buffer,
	ctx->epg_buffers[i].buffer_length);
	}
	}

[ccextractor-bot]

CCExtractor CI platform finished running the test files on linux. Below is a summary of the test results, when compared to test for commit f377be9...:

Report Name	Tests Passed
Broken	13/13
CEA-708	14/14
DVB	7/7
DVD	3/3
DVR-MS	2/2
General	27/27
Hardsubx	1/1
Hauppage	3/3
MP4	3/3
NoCC	10/10
Options	86/86
Teletext	21/21
WTV	13/13
XDS	34/34

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

All tests passed completely.

Check the result page for more info.

[ccextractor-bot]

CCExtractor CI platform finished running the test files on windows. Below is a summary of the test results, when compared to test for commit f377be9...:

Report Name	Tests Passed
Broken	13/13
CEA-708	14/14
DVB	6/7
DVD	3/3
DVR-MS	2/2
General	25/27
Hardsubx	1/1
Hauppage	3/3
MP4	3/3
NoCC	10/10
Options	80/86
Teletext	21/21
WTV	13/13
XDS	34/34

Your PR breaks these cases:

• ccextractor --autoprogram --out=srt --latin1 --quant 0 85271be4d2...
• ccextractor --autoprogram --out=ttxt --latin1 --ucla dab1c1bd65...
• 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 --startcreditsnotafter 2 --startcreditstext "CCextractor Start crdit Testing" c4dd893cb9...
• ccextractor --startcreditsforatleast 1 --startcreditstext "CCextractor Start crdit Testing" c4dd893cb9...
• ccextractor --startcreditsforatmost 2 --startcreditstext "CCextractor Start crdit Testing" c4dd893cb9...

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.

[Varadraj75]

The Windows CI failures are pre-existing and unrelated to this change:

• All failing tests show Empty path name is not legal — a Windows path
  handling issue in the test runner
• All failing tests show "Last passed: Never" in the CI bot summary,
  confirming they were already failing on master before this PR
• Linux CI passes all tests cleanly

This PR only modifies EPG_free() in ts_tables_epg.c which has no
interaction with path handling or the failing test cases.