Re: [sysvinit-devel] [PATCH] automatically spawn agetty on kernel consoles
Dr. Werner Fink <werner <at> suse.de>
2011-06-21 11:27:37 GMT
On Thu, May 26, 2011 at 08:23:30AM +0200, Ludwig Nussel wrote:
> The feature is useful for developers and admins that occasionally need
> to boot with e.g. console=ttyS0.
> The built in default can be overridden via inittab for each device. An
> entry like "S0::off:" turns off the getty on ttyS0.
> ---
> src/init.c | 74 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
> 1 files changed, 74 insertions(+), 0 deletions(-)
Ludwig?
Please check out the code of src/consoles.c and src/consoles.h
which does a similar job by not only using "/proc/cmdline" but
also "/proc/consoles" or "/sys/class/tty" if available.
Nonetheless a configure option as mentioned by Mike should be also
added.
Werner
> diff --git a/src/init.c b/src/init.c
> index d379fb2..13deef7 100644
> --- a/src/init.c
> +++ b/src/init.c
> <at> <at> -1243,6 +1243,76 <at> <at> void startup(CHILD *ch)
> }
> }
>
> +#ifdef __linux__
> +static
> +void check_kernel_console()
> +{
> + FILE* fp;
> + char buf[4096];
> + if ((fp = fopen("/proc/cmdline", "r")) == 0) {
> + return;
> + }
> + if (fgets(buf, sizeof(buf), fp)) {
> + char* p = buf;
> + while ((p = strstr(p, "console="))) {
> + char* e;
> + p += strlen("console=");
> + for (e = p; *e; ++e) {
> + switch (*e) {
> + case '-' ... '9':
> + case 'A' ... 'Z':
> + case '_':
> + case 'a' ... 'z':
> + continue;
> + }
> + break;
> + }
> + if (p != e) {
> + CHILD* old;
> + int dup = 0;
> + char id[8] = {0};
> + char dev[32] = {0};
> + strncpy(dev, p, MIN(sizeof(dev), (unsigned)(e-p)));
> + if (!strncmp(dev, "tty", 3))
> + strncpy(id, dev+3, sizeof(id));
> + else
> + strncpy(id, dev, sizeof(id));
> +
> + for(old = newFamily; old; old = old->next) {
> + if (!strcmp(old->id, id)) {
> + dup = 1;
> + }
> + }
> + if (!dup) {
> + CHILD* ch = imalloc(sizeof(CHILD));
> + ch->action = RESPAWN;
> + strcpy(ch->id, id);
> + strcpy(ch->rlevel, "2345");
> + sprintf(ch->process, "/sbin/agetty -L -s 115200,38400,9600 %s vt102", dev);
> + ch->next = NULL;
> + for(old = family; old; old = old->next) {
> + if (strcmp(old->id, ch->id) == 0) {
> + old->new = ch;
> + break;
> + }
> + }
> + /* add to end */
> + for(old = newFamily; old; old = old->next) {
> + if (!old->next) {
> + old->next = ch;
> + break;
> + }
> + }
> +
> + initlog(L_VB, "added agetty on %s with id %s", dev, id);
> + }
> + }
> + }
> + }
> + fclose(fp);
> + return;
> +}
> +#endif
>
> /*
> * Read the inittab file.
> <at> <at> -1455,6 +1525,10 <at> <at> void read_inittab(void)
> */
> if (fp) fclose(fp);
>
> +#ifdef __linux__
> + check_kernel_console();
> +#endif
> +
> /*
> * Loop through the list of children, and see if they need to
> * be killed.
> --
> 1.7.3.4
>
--
--
Dr. Werner Fink -- Software Engineer Consultant
SuSE LINUX Products GmbH, Maxfeldstrasse 5, Nuernberg, Germany
GF: Jeff Hawn, Jennifer Guild, Felix Imendörffer, HRB 21284 (AG Nuernberg)
phone: +49-911-740-53-0, fax: +49-911-3206727, www.opensuse.org
------------------------------------------------------------------
"Having a smoking section in a restaurant is like having
a peeing section in a swimming pool." -- Edward Burr
RSS Feed