Logging¶

There is no clean logging concept at the moment.

• Low footprint
• Work within ISRs. The output is delayed. The order is preserved.
• Only short messages, e.g. 20 chars.
• Heart-beat LED might be involved
• CAN might be involved to transmit diagnose
• Debug can be disabled even for Debug-builds; BIWAK_LOG_DEBUG has to be defined to show bDebug

Heartbeat-Class¶

An LED can indicate problems.

• good (double heartbeat)
• warning; temporary error/ trouble (fast blink - off 1Hz) (goes away)
• critical error/ exception (fast blink)
• fatal error (slow blink)

Usecases¶

• invalid eeprom causes "critical"-state
• Not being able to sen CAN messages causes "trouble"
• fatal: the application can not run for some reason but the led should work; e.g. a reception buffer is full
• exception: Don't even try to run any more. e.g. memory error.

Notes¶

There is already a doublebuffer-class for CAN.

Examples¶

add_definitions( BIWAK_LOG_HEARTBEAT )
add_definitions( BIWAK_LOG_CAN )
add_definitions( BIWAK_LOG_DEBUG )

#define bDebug(a,...) debug(a, __VA_ARGS__)

#include <biwak/log.hpp>

main()
{
   bDebug();      // Just print some text
   bCritical();
   bTrouble();    // 
   bFatal();
   bException("Static text");
}

static struct {
    char buf[20];
    bool used;
}buffers[2]={0};

void bWarning(const char *text, ...)
{
    va_list list;
    va_start(list, text);
    int bufid;
    for(bufid=0; bufid < ARRAY_ELEMENTS(buffers); bufid++)
    {
        if(!buffers[bufid].used)
        {
            break;
        }
    }
    if(bufid >= ARRAY_ELEMENTS(buffers))
    {
        bException("Out of log buffers!");
    }
    buffers[bufid].used=true;
    vsnprintf(buffers[bufid].buf, 20, text, list);
    puts(buffers[bufid].buf);
    printf("Bufid: %d; elements: %d\n", bufid, ARRAY_ELEMENTS(buffers));
};