demo_app.c

完整的Bell实验室的嵌入式文件系统TFS

/* demo_app.c:
 * This file is a simple example of an application that could be run
 * on top of the monitor.
 *
 * start():
 * The start() function depends on the setting of MONCOMPTR in config.h.
 * It demonstrates the use of monConnect and the first mon_XXX function
 * typically called by an application, mon_getargv().
 *
 * main():
 * The main() function demonstrates argument processing (thanks to
 * the call to mon_getargv() in start()), environment variables and
 * a simple use of TFS to dump the content of an ASCII file.
 */

#include "config.h"
#include "monlib.h"
#include "tfs.h"
#include "stddefs.h"

int
main(int argc,char *argv[])
{
    int     i, tfd;
    char    line[80], *fname;

    /* If argument count is greater than one, then dump out the
     * set of CLI arguments...
     */
    if (argc > 1) {
        mon_printf("Argument list...\n");
        for(i=0;i<argc;i++)
            mon_printf("  arg[%d]: %s\n",i,argv[i]);
    }

    /* If the shell variable "USE_THIS_FILE" exists, then use the
     * content of that shell variable as a filename; else use "monrc"...
     */
    fname = mon_getenv("USE_THIS_FILE");
    if (!fname)
        fname = "monrc";

    /* If the file exists, the assume it is ASCII and dump it
     * line by line...
     */
    if (mon_tfsstat(fname)) {
        mon_printf("Dumping content of '%s'...\n",fname);

        tfd = mon_tfsopen(fname,TFS_RDONLY,0);
        if (tfd >= 0) {
            while(mon_tfsgetline(tfd,line,sizeof(line)))
                mon_printf("%s",line);
            mon_tfsclose(tfd,0);
        }
        else {
            mon_printf("TFS error: %s\n",
                (char *)mon_tfsctrl(TFS_ERRMSG,tfd,0));
        }
    }
    return(0);
}

void
__eabi(void)
{
}

int
start(void)
{
    char    **argv;
    int     argc;

    /* Connect the application to the monitor.  This must be done
     * prior to the application making any other attempts to use the
     * "mon_" functions provided by the monitor.
     */
    monConnect((int(*)())(*(unsigned long *)MONCOMPTR),(void *)0,(void *)0);

    /* Extract argc/argv from structure and call main():
     */
    mon_getargv(&argc,&argv);

    /* Call main, then return to monitor.
     */
    return(main(argc,argv));
}