Kannel: Open Source WAP and SMS gateway  $Revision: 5037 $
gwpoll.h File Reference

Go to the source code of this file.

Data Structures

struct  pollfd
 

Macros

#define POLLIN   1 /* Reading will not block */
 
#define POLLPRI   2 /* Urgent data available for reading */
 
#define POLLOUT   4 /* Writing will not block */
 
#define POLLERR   8 /* Error condition */
 
#define POLLHUP   16 /* Hung up: fd was closed by other side */
 
#define POLLNVAL   32 /* Invalid: fd not open or not valid */
 
#define POLL_NOTIMEOUT   (-1)
 
#define poll(fdarray, numfds, timeout)   gw_poll(fdarray, numfds, timeout)
 

Functions

int gw_poll (struct pollfd *fdarray, unsigned int numfds, int timeout)
 

Macro Definition Documentation

#define poll (   fdarray,
  numfds,
  timeout 
)    gw_poll(fdarray, numfds, timeout)

Definition at line 104 of file gwpoll.h.

Referenced by gwthread_poll(), gwthread_pollfd(), and gwthread_sleep().

#define POLL_NOTIMEOUT   (-1)

Definition at line 100 of file gwpoll.h.

Referenced by gwthread_poll(), gwthread_pollfd(), and gwthread_sleep().

#define POLLERR   8 /* Error condition */

Definition at line 96 of file gwpoll.h.

Referenced by conn_flush(), conn_wait(), poll_callback(), and poller().

#define POLLHUP   16 /* Hung up: fd was closed by other side */

Definition at line 97 of file gwpoll.h.

Referenced by conn_flush(), conn_wait(), and poll_callback().

#define POLLNVAL   32 /* Invalid: fd not open or not valid */

Definition at line 98 of file gwpoll.h.

Referenced by conn_flush(), conn_wait(), and gw_poll().

#define POLLOUT   4 /* Writing will not block */
#define POLLPRI   2 /* Urgent data available for reading */

Definition at line 92 of file gwpoll.h.

Referenced by gw_poll().

Function Documentation

int gw_poll ( struct pollfd fdarray,
unsigned int  numfds,
int  timeout 
)

Definition at line 67 of file gwpoll.c.

References pollfd::events, pollfd::fd, POLLIN, POLLNVAL, POLLOUT, POLLPRI, and pollfd::revents.

68 {
69  struct timeval tv, *tvp;
70  unsigned int i;
71  int maxfd;
72  fd_set readfds, *rfdp;
73  fd_set writefds, *wfdp;
74  fd_set exceptfds, *xfdp;
75  int ret;
76  int result;
77 
78  FD_ZERO(&readfds);
79  FD_ZERO(&writefds);
80  FD_ZERO(&exceptfds);
81  maxfd = -1;
82  /* These are the pointers we will pass to select(). We use them because
83  * we may want to pass NULL for some of them. */
84  tvp = NULL;
85  rfdp = NULL;
86  wfdp = NULL;
87  xfdp = NULL;
88 
89  /* Deal with timeout. We get it in milliseconds. If it's negative,
90  * block indefinitely, which we do in select() by passing a NULL
91  * timeval pointer. */
92  if (timeout >= 0) {
93  tv.tv_sec = timeout / 1000;
94  tv.tv_usec = (timeout % 1000) * 1000;
95  tvp = &tv;
96  }
97 
98  /* Deal with fdarray, and convert it to the three fd_sets used by select. */
99  for (i = 0; i < numfds; i++) {
100  int fd = fdarray[i].fd;
101  int events = fdarray[i].events;
102  if (fd < 0)
103  continue;
104  if (events & POLLIN) {
105  FD_SET(fd, &readfds);
106  rfdp = &readfds;
107  }
108  if (events & POLLOUT) {
109  FD_SET(fd, &writefds);
110  wfdp = &writefds;
111  }
112  if (events & POLLPRI) {
113  FD_SET(fd, &exceptfds);
114  xfdp = &exceptfds;
115  }
116  if (fd > maxfd && events & (POLLIN | POLLOUT | POLLPRI))
117  maxfd = fd;
118  }
119 
120  ret = select(maxfd + 1, rfdp, wfdp, xfdp, tvp);
121  if (ret < 0)
122  return ret;
123 
124  /* Move the returned data from the fd sets to the revents fields
125  * in fdarray. We can't detect POLLNVAL except for obviously
126  * invalid fd's, and detecting POLLHUP or POLLERR would require
127  * an extra read() call per fd which is too expensive. */
128  result = 0;
129  for (i = 0; i < numfds; i++) {
130  if (fdarray[i].fd < 0) {
131  fdarray[i].revents = POLLNVAL;
132  continue;
133  }
134  fdarray[i].revents = 0;
135  if (rfdp && FD_ISSET(fdarray[i].fd, &readfds))
136  fdarray[i].revents |= POLLIN;
137  if (wfdp && FD_ISSET(fdarray[i].fd, &writefds))
138  fdarray[i].revents |= POLLOUT;
139  if (xfdp && FD_ISSET(fdarray[i].fd, &exceptfds))
140  fdarray[i].revents |= POLLPRI;
141  if (fdarray[i].revents != 0)
142  result++;
143  }
144 
145  return result;
146 }
#define POLLNVAL
Definition: gwpoll.h:98
short events
Definition: gwpoll.h:86
#define POLLPRI
Definition: gwpoll.h:92
#define POLLIN
Definition: gwpoll.h:91
int fd
Definition: gwpoll.h:85
short revents
Definition: gwpoll.h:87
#define POLLOUT
Definition: gwpoll.h:93
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