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/* for broken bsd's */
#include <sys/time.h>
#include <sys/types.h>
#include <unistd.h>
/* for unix systems */
#include <sys/select.h>
#include <string.h>
#include <inttypes.h>
static unsigned char *vec_ri, *vec_ro, *vec_wi, *vec_wo;
static int vec_max;
static void
select_modify (int fd, int oev, int nev)
{
int offs = fd >> 3;
int mask = 1 << (fd & 7);
if (vec_max < (fd >> 5) + 1)
{
vec_max = (fd >> 5) + 1;
vec_ri = (unsigned char *)realloc (vec_ri, vec_max * 4);
vec_ro = (unsigned char *)realloc (vec_ro, vec_max * 4); /* could free/malloc */
vec_wi = (unsigned char *)realloc (vec_wi, vec_max * 4);
vec_wo = (unsigned char *)realloc (vec_wo, vec_max * 4); /* could free/malloc */
}
vec_ri [offs] |= mask;
if (!(nev & EV_READ))
vec_ri [offs] &= ~mask;
vec_wi [offs] |= mask;
if (!(nev & EV_WRITE))
vec_wi [offs] &= ~mask;
}
static void select_poll (ev_tstamp timeout)
{
struct timeval tv;
int res;
memcpy (vec_ro, vec_ri, vec_max * 4);
memcpy (vec_wo, vec_wi, vec_max * 4);
tv.tv_sec = (long)timeout;
tv.tv_usec = (long)((timeout - (ev_tstamp)tv.tv_sec) * 1e6);
res = select (vec_max * 32, (fd_set *)vec_ro, (fd_set *)vec_wo, 0, &tv);
if (res > 0)
{
int word, offs;
for (word = vec_max; word--; )
{
if (((uint32_t *)vec_ro) [word] | ((uint32_t *)vec_wo) [word])
for (offs = 4; offs--; )
{
int idx = word * 4 + offs;
unsigned char byte_r = vec_ro [idx];
unsigned char byte_w = vec_wo [idx];
int bit;
if (byte_r | byte_w)
for (bit = 8; bit--; )
{
int events = 0;
events |= byte_r & (1 << bit) ? EV_READ : 0;
events |= byte_w & (1 << bit) ? EV_WRITE : 0;
if (events)
fd_event (idx * 8 + bit, events);
}
}
}
}
}
void select_init (int flags)
{
ev_method = EVMETHOD_SELECT;
method_fudge = 1e-2; /* needed to compensate for select returning early, very conservative */
method_modify = select_modify;
method_poll = select_poll;
}
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