WinDriver/win31drv/log.c

// ============================================================================
// log.c - Logging to file
//
// Simple dual-output logger: messages go to a log file (opened by
// logInit) and optionally to stdout (logMsg) or stderr (logErr).
// An optional pre-I/O hook is called before every write, used by
// windrv.c to ensure the S3 engine is idle before file I/O (DOSBox-X
// processes S3 operations during file writes).
// ============================================================================

#include <stdio.h>
#include <stdarg.h>

#include "log.h"

static FILE          *gLogFile   = NULL;
static LogPreIoFuncT  gPreIoHook = NULL;


void logInit(const char *filename)
{
    if (filename) {
        gLogFile = fopen(filename, "w");
    }
}


void logErr(const char *fmt, ...)
{
    va_list ap;
    va_start(ap, fmt);
    logErrV(fmt, ap);
    va_end(ap);
}


void logErrV(const char *fmt, va_list ap)
{
    if (gLogFile) {
        if (gPreIoHook) {
            gPreIoHook();
        }
        vfprintf(gLogFile, fmt, ap);
        fflush(gLogFile);
    }
}


FILE *logGetFile(void)
{
    return gLogFile;
}


void logMsg(const char *fmt, ...)
{
    va_list ap;
    va_start(ap, fmt);
    logMsgV(fmt, ap);
    va_end(ap);
}


void logMsgV(const char *fmt, va_list ap)
{
    if (gLogFile) {
        if (gPreIoHook) {
            gPreIoHook();
        }
        vfprintf(gLogFile, fmt, ap);
        fflush(gLogFile);
    }
}


void logSetPreIoHook(LogPreIoFuncT func)
{
    gPreIoHook = func;
}


void logShutdown(void)
{
    if (gLogFile) {
        fflush(gLogFile);
        fclose(gLogFile);
        gLogFile = NULL;
    }
}