| # About |
| |
| This library provides logging related features, like logging macros, to drivers. |
| |
| # Why separate lib? |
| |
| Drivers need to use this separate library, rather than existing logging libraries for the |
| following reasons: |
| |
| - Globals not available per driver |
| |
| ## Globals not available per driver |
| |
| Elf components use the syslog library to create logs. This is a shared library that is shared by |
| everything in the process. |
| |
| If driver components were to use the same library, then all logs that are emitted from a driver |
| host would go out of the same logger. This includes the driver host itself, as well as all drivers |
| sharing the host. Therefore this option does not fit our criteria. |
| |
| Another option is to provide the syslog methods through the driver runtime. This is because |
| the driver runtime can track the currently active driver. But this is only true in the ideal case |
| where Banjo doesn't exist, since Banjo calls can cross driver boundaries through function calls. |
| This makes the tracking in the driver runtime not completely accurate today. This option also does |
| not fit our criteria. |
| |
| Instead the route we have currently chosen is to use a global that is statically linked to just |
| the driver to store the logger. The downside with this is that logs coming from multiple instances |
| of the same driver in the host all go out of the same logger. We are ok with this tradeoff as it |
| simplifies the logging macros and avoids forcing the user to pass a logger in manually. |
