Sukadev Bhattiprolu wrote:
> Daniel Lezcano [dlezcano@xxxxxxxxxx] wrote:
>>> +find_cinit_pid(const char *name)
>>> {
>>> + struct lxc_command command = {
>>> + .request = { .type = LXC_COMMAND_CINIT_PID },
>>> + };
>>> +
>>> + int ret, stopped;
>>> +
>>> + ret = lxc_command(name, &command, &stopped);
>>> + if (ret < 0) {
>>> + ERROR("failed to send command");
>>> + return -1;
>>> + }
>>> +
>>> + ERROR("find_cinit_pid %d\n", command.answer.ret);
>>> +
>>> + return command.answer.ret;
>>> +}
>> I just committed the same function for the lxc_attach command. I think
>> you can reuse it.
>
> Ok, will try to reuse it.
>
>>> +int lxc_checkpoint(const char *name, const char *statefile, int lxc_flags)
>>> +{
>>> + int ret;
>>> + int pid;
>>> + int flags;
>>> + struct stat statbuf;
>>> + struct app_checkpoint_args crargs;
>>> +
>>> + if (access(statefile, F_OK) == 0) {
>>> + ret = stat(statefile, &statbuf);
>>> + if (ret < 0) {
>>> + ERROR("stat(%s): %s\n", statefile, strerror(errno));
>>> + return -1;
>>> + }
>>> +
>>> + if (S_ISDIR(statbuf.st_mode)) {
>>> + ERROR("--directory option not implemented");
>>> + return -1;
>>> + } else {
>>> + ERROR("Checkpoint image file %s exists\n", statefile);
>>> + return -1;
>>> + }
>>> + }
>> For the checkpoint, you don't need to check if it's a directory or a
>> file (but it should be done at restart time).
>
> I need to open() the statefile and pass its fd to app_checkpoint().
> If I don't check for directory, the open() below would fail, only
> because of the O_RDWR flag. By checking, we could give a more useful
> error message ?
What I meant is the directory shall not exists when checkpointing, if
the directory or the file exists, the checkpoint should fail.
>> I am not sure 'access' is
>> really necessary because the O_EXCL is set in the open below.
>
> Agree. How about just the stat() and the error message ?
IMO, just fail when trying to open the file, the O_EXCL flag will do the
job for us.
> Maybe later we could bury this code under say #ifdef USERCR so
> if LXC is configured without USERCR, the current behavior is preserved ?
Right, it's an aspect we have to address. But we can do that later, IMHO
the main objective would be to correctly integrate lxc and the CR with
the 'configure' script. eg configure --with-linux=<path> .... and the
makefiles.
_______________________________________________
Containers mailing list
Containers@xxxxxxxxxxxxxxxxxxxxxxxxxx
https://lists.linux-foundation.org/mailman/listinfo/containers
