[FIX] networking.c: replace DEBUG_OUT integer toggle with CMake opt-in; fix error messages using printf() instead of fprintf(stderr)

[Varadraj75]

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Summary

Fixes #2174 — two related bugs in src/lib_ccx/networking.c.

Fix 1 — Replace DEBUG_OUT integer toggle with CMake opt-in

#define DEBUG_OUT 0 caused debug code to always be compiled into
production builds, just silenced at runtime. This is the same pattern
fixed for VBI_DEBUG in #2168.

Removed the #define DEBUG_OUT 0 and replaced all #if DEBUG_OUT
guards with #ifdef NETWORKING_DEBUG, then added a proper CMake option:

option (NETWORKING_DEBUG "Enable networking debug output" OFF)

if (NETWORKING_DEBUG)
  add_definitions(-DNETWORKING_DEBUG)
  message(STATUS "Networking debug output enabled")
endif (NETWORKING_DEBUG)

Developers who need networking debug output can now opt in explicitly:

cmake .. -DNETWORKING_DEBUG=ON

Fix 2 — Replace printf() with fprintf(stderr) for error messages

Three error conditions were writing to stdout instead of stderr:

printf("Can't send BIN header\n");   // line 153
printf("Can't send BIN data\n");     // line 180
printf("Unable to send data\n");     // line 240

This means network errors are silently swallowed when stdout is
redirected, e.g. ccextractor input.ts > output.srt. All three
have been changed to fprintf(stderr, ...), consistent with the
rest of the error handling in the same file.

Testing

Built and verified locally on macOS with both NETWORKING_DEBUG=OFF
(default) and NETWORKING_DEBUG=ON. All existing CI tests pass.

Fixes #2174

[Copilot]

Pull request overview

This PR addresses #2174 by making networking debug output an explicit CMake opt-in (instead of being always compiled) and by routing networking error messages to stderr.

Changes:

• Replace DEBUG_OUT integer toggle with #ifdef NETWORKING_DEBUG in src/lib_ccx/networking.c.
• Add a NETWORKING_DEBUG CMake option to enable networking debug output at compile time.
• Switch several network send failure messages from printf() (stdout) to fprintf(stderr, ...) (stderr).

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 5 comments.

File	Description
src/lib_ccx/networking.c	Gates debug logging behind NETWORKING_DEBUG and sends error messages to stderr.
src/CMakeLists.txt	Introduces a CMake option/define to enable NETWORKING_DEBUG.
docs/CHANGES.TXT	Adds a changelog entry for the fixes.

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[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.