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Logging

SIPNET's logger is a small wrapper around printf that adds standard prefixes and, for internal errors, the source file and line number. It is defined in common/logging.h and implemented in common/logging.c.

Levels

  • 0: Quiet-able (suppressed by --quiet).
  • 1: Always on (not suppressed).
  • 2: Always on and includes file:line.

Functions

  • logInfo: Level 0; routine progress, expected or supported behavior, configuration summaries, and transparency messages.
  • logWarning: Level 0; conditions that may affect validity or reliability, or likely require user attention.
  • logTest: Level 1; deterministic messages for tests/CI; not user-facing.
  • logError: Level 1; non-recoverable problems: the run cannot continue, state is invalid, or output cannot be trusted.
  • logInternalError: Level 2; errors that should never happen; include details and ask to report.
  • logAppend: Level 0; continue the current log message (for example, to add more text after a logInfo call) without starting a new prefix.

Note that logAppend messages are hidden by --quiet regardless of the log level of the previous log line.

Choosing a function

Rule of thumb:

  • Use logError if the run should stop.
  • Use logWarning if the user should probably stop and check the run.
  • Use logInfo if the run can proceed and the message is mainly for transparency.

Usage

  1. Include the header: 
    #include "common/logging.h"
  2. Log messages: 
    logInfo("Initialized OK\n");
logWarning("Deprecated parameter: %s\n", name);
logTest("Iteration %d\n", i);
logError("Missing required parameter: %s\n", key);
logInternalError("Unexpected state: %d\n", code);
  3. Example outputs: 
    [INFO   ] Initialized OK
[WARNING] Deprecated parameter: foo
[TEST   ] Iteration 12
[ERROR  ] Missing required parameter: bar
[ERROR (INTERNAL)] (myfile.c:123) Unexpected state: 5

Notes

  • Each logging function (except logAppend) prints a fixed prefix (e.g., [INFO ], [WARNING], [ERROR ]).
  • Messages use printf-style formatting. Include \n yourself if you want a newline.
  • Level 2 (logInternalError) prints file:line; levels 0–1 print just the prefix.