Re: Current LibXL Status

[Andrew Cooper <andrew.cooper3@citrix.com>]

On 19/11/15 11:23, Ian Campbell wrote:
> create !
> title it libxl exit() on ENOMEM incompatible with gc'd languages
> thanks

Can this be extended to "should not use exit() in general" ?

andrewcoop@andrewcoop:/local/xen.git/xen$ git grep exit\( --
:/tools/libxl/libxl*
../tools/libxl/libxl.c:1707:        _exit(0);
../tools/libxl/libxl.c:1711:            _exit(errno);
../tools/libxl/libxl.c:1716:            _exit(-1);
../tools/libxl/libxl_aoutils.c:478:            if (r) {
LOGE(ERROR,"openpty failed"); _exit(-1); }
../tools/libxl/libxl_aoutils.c:482:        if (rc) { LOGE(ERROR,"sendmsg
to parent failed"); _exit(-1); }
../tools/libxl/libxl_aoutils.c:483:        _exit(0);
../tools/libxl/libxl_bootloader.c:557:        if (r) { LOGE(ERROR,
"login_tty failed"); exit(-1); }
../tools/libxl/libxl_bootloader.c:559:        exit(-1);
../tools/libxl/libxl_event.c:1387:    exit(-1);
../tools/libxl/libxl_event.h:104:   * and call exit(-1).
../tools/libxl/libxl_exec.c:106:    _exit(-1);
../tools/libxl/libxl_exec.c:316:        exit(255);
../tools/libxl/libxl_exec.c:324:        _exit(127);
../tools/libxl/libxl_exec.c:340:    _exit(r);
../tools/libxl/libxl_internal.c:28:    _exit(-1);
../tools/libxl/libxl_remus_disk_drbd.c:229:    _exit(ackwait);
../tools/libxl/libxl_save_callout.c:184:                exit(-1);
../tools/libxl/libxl_save_helper.c:64:    if (r < 0) { perror("memory
allocation failed during logging"); exit(-1); }
../tools/libxl/libxl_save_helper.c:102:    exit(-1);
../tools/libxl/libxl_save_helper.c:122:    if (!r) { perror("memory
allocation failed"); exit(-1); }
../tools/libxl/libxl_save_helper.c:189:        if (r<0) {
perror("write"); exit(-1); }
../tools/libxl/libxl_save_helper.c:210:    if (r<=0) exit(-2);
../tools/libxl/libxl_save_helper.c:230:    exit(0);
../tools/libxl/libxlu_cfg_l.c:1763:     exit( YY_EXIT_FAILURE );
../tools/libxl/libxlu_disk_l.c:2248:    exit( YY_EXIT_FAILURE );

The majority of those are cases are not appropriate uses of exit(). 
AFAIIR, the *only* valid use of exit() in a library is to clean up in a
child process from a library-initiated fork().

~Andrew