[PATCH v3] libcamera: log: Match whole category in LIBCAMERA_LOG_LEVELS

[Kieran Bingham]

Quoting Stefan Klug (2025-01-23 09:04:18)
> A LIBCAMERA_LOG_LEVELS value of "RkISP1:0" also applies to RkISP1Ccm and
> RkISP1Awb. This behavior is unexpected as it automatically enables all
> algorithm log categories when the intent is only to increase the log
> level of the upper category. Fix that replacing the manual matching code
> with fnmatch. This has the side effect that more wildcards ("?" and
> "[...]") are supported which is acceptable but won't be advertised.
> 
> Signed-off-by: Stefan Klug <stefan.klug at ideasonboard.com>
> Reviewed-by: Laurent Pinchart <laurent.pinchart at ideasonboard.com>
> 

Or even this one too.

If only there was a way to keep a specific work topic all bundled
together in a centralised way. :-(

Reviewed-by: Kieran Bingham <kieran.bingham at ideasonboard.com>

> ---
> 
> Changes in v2:
> - Replaced matching code with fnmatch instead of a manual fix
> 
> Changes in v3:
> - Collected tag
> - Updated documentation to no longer restrict the wildcard to the end
>   of the string
> ---
>  src/libcamera/base/log.cpp | 26 ++++++--------------------
>  1 file changed, 6 insertions(+), 20 deletions(-)
> 
> diff --git a/src/libcamera/base/log.cpp b/src/libcamera/base/log.cpp
> index 3a656b8f099f..72e0db859943 100644
> --- a/src/libcamera/base/log.cpp
> +++ b/src/libcamera/base/log.cpp
> @@ -8,6 +8,7 @@
>  #include <libcamera/base/log.h>
>  
>  #include <array>
> +#include <fnmatch.h>
>  #include <fstream>
>  #include <iostream>
>  #include <list>
> @@ -38,8 +39,8 @@
>   * The levels are configurable through the LIBCAMERA_LOG_LEVELS environment
>   * variable that contains a comma-separated list of 'category:level' pairs.
>   *
> - * The category names are strings and can include a wildcard ('*') character at
> - * the end to match multiple categories.
> + * The category names are strings and can include a wildcard ('*') character to
> + * match multiple categories.
>   *
>   * The level are either numeric values, or strings containing the log level
>   * name. The available log levels are DEBUG, INFO, WARN, ERROR and FATAL. Log
> @@ -717,24 +718,9 @@ void Logger::registerCategory(LogCategory *category)
>         categories_.push_back(category);
>  
>         const std::string &name = category->name();
> -       for (const std::pair<std::string, LogSeverity> &level : levels_) {
> -               bool match = true;
> -
> -               for (unsigned int i = 0; i < level.first.size(); ++i) {
> -                       if (level.first[i] == '*')
> -                               break;
> -
> -                       if (i >= name.size() ||
> -                           name[i] != level.first[i]) {
> -                               match = false;
> -                               break;
> -                       }
> -               }
> -
> -               if (match) {
> -                       category->setSeverity(level.second);
> -                       break;
> -               }
> +       for (const auto &[pattern, severity] : levels_) {
> +               if (fnmatch(pattern.c_str(), name.c_str(), FNM_NOESCAPE) == 0)
> +                       category->setSeverity(severity);
>         }
>  }
>  
> -- 
> 2.43.0
>