enum BC_INIT_STATUS
bc_init_controlinfo(struct buildcmd_control *ctl,
size_t headroom)
{
size_t size_of_environment = bc_size_of_environment();
/* POSIX requires that _POSIX_ARG_MAX is 4096. That is the lowest
* possible value for ARG_MAX on a POSIX compliant system. See
* http://www.opengroup.org/onlinepubs/009695399/basedefs/limits.h.html
*/
ctl->posix_arg_size_min = _POSIX_ARG_MAX;
ctl->posix_arg_size_max = bc_get_arg_max();
ctl->exit_if_size_exceeded = 0;
/* Take the size of the environment into account. */
if (size_of_environment > ctl->posix_arg_size_max)
{
return BC_INIT_ENV_TOO_BIG;
}
else if ((headroom + size_of_environment) >= ctl->posix_arg_size_max)
{
/* POSIX.2 requires xargs to subtract 2048, but ARG_MAX is
* guaranteed to be at least 4096. Although xargs could use an
* assertion here, we use a runtime check which returns an error
* code, because our caller may not be xargs.
*/
return BC_INIT_CANNOT_ACCOMODATE_HEADROOM;
}
else
{
ctl->posix_arg_size_max -= size_of_environment;
ctl->posix_arg_size_max -= headroom;
}
/* need to subtract 2 on the following line - for Linux/PPC */
ctl->max_arg_count = (ctl->posix_arg_size_max / sizeof(char*)) - 2u;
assert (ctl->max_arg_count > 0);
ctl->rplen = 0u;
ctl->replace_pat = NULL;
ctl->initial_argc = 0;
ctl->exec_callback = cb_exec_noop;
ctl->lines_per_exec = 0;
ctl->args_per_exec = 0;
/* Set the initial value of arg_max to the largest value we can
* tolerate.
*/
ctl->arg_max = ctl->posix_arg_size_max;
return BC_INIT_OK;
}
void
bc_init_controlinfo(struct buildcmd_control *ctl)
{
long arg_max = bc_get_arg_max();
assert(arg_max > 0);
ctl->exit_if_size_exceeded = 0;
ctl->arg_max = arg_max - 2048; /* a la xargs */
/* need to subtract 2 on the following line - for Linux/PPC */
ctl->max_arg_count = (arg_max / sizeof(void*)) - 2;
assert(ctl->max_arg_count > 0);
ctl->rplen = 0u;
ctl->replace_pat = NULL;
ctl->initial_argc = 0;
ctl->exec_callback = cb_exec_noop;
ctl->lines_per_exec = 0;
ctl->args_per_exec = 0;
}
