silence warnings from code
When exiv2 is scanning the metadata of images, it often outputs warnings about minor problems on the console that makes it difficult to find messages about more acute problems. I know that one can run ./configure with -DSUPPRESS_WARNINGS to get it more quiet, but I reckon many users will have "apt-get installed" exiv2 rather than compiling it for themselves.
How about changing all the lines that now does e.g.
std:cerr << "Blah blah";
so that they instead call some central message-output method and also supply a severity level with the message.
Then, the code that calls exiv2 methods could call some method to set a threshold for which messages are passed thru to cerr.
#476, #614: Introduced class LogMsg for enhanced logging, migrated all existing warnings and error messages (not the exceptions) to use the new logic. Every log message now has a type (debug, info, warning, error). Applications can set a logging level to determine which messages are processed and supply a custom log message handler at runtime. (Based on a contribution by Simson Garfinkel.)
Updated by Andreas Huggel over 8 years ago
- Category changed from basicio to design
- Status changed from New to Resolved
- Target version set to 0.21
- % Done changed from 0 to 100
Applications can now set the log level to determine which log messages they are interested in:
// Set the log level to only show errors (and suppress warnings, informational and debug messages) Exiv2::LogMsg::setLevel(Exiv2::LogMsg::error);
To suppress all log messages set the log level to
Exiv2::LogMsg::mute or set the log message handler to
0 (see #476).
For more details, see the new class
The SUPPRESS_WARNINGS mechanism still exists, in case there is a need to avoid compiling the log messaging calls in the library completely.