vde-2/packetq.c

   1 /*
   2  * packetq - packet queue management. try to send packets several times before discarding.
   3  * Copyright 2005 Renzo Davoli
   4  * Licensed under the GPLv2
   5  */
   6
   7 #include <config.h>
   8 #include <stdlib.h>
   9 #include <stdio.h>
  10 #include <string.h>
  11 #include <sys/time.h>
  12 #include <time.h>
  13 #include <sys/types.h>
  14 #include <unistd.h>
  15 #include <errno.h>
  16 #include <syslog.h>
  17
  18 #include <consmgmt.h>
  19 #include <vde.h>
  20
  21 #ifdef VDE_PQ
  22 #include "packetq.h"
  23
  24 int packetq_timeout= -1;
  25 static int countq;
  26 #define TIMEOUT 5
  27 #define TIMES 10
  28 #define MAXQLEN 4192
  29
  30 struct packetqq {
  31         int (*sender)(int fd, int fd_ctl, void *packet, int len, void *data, int port);
  32         int fd;
  33         int fd_ctl;
  34         void *packet;
  35         int len;
  36         void *data;
  37         int port;
  38         int times;
  39         struct packetqq *next;
  40 };
  41
  42 static struct packetqq *pqh=NULL;
  43 static struct packetqq *pqt=NULL;
  44 static struct timeval last_try;
  45
  46 void packetq_add(int (*sender)(int fd, int fd_ctl, void *packet, int len, void *data, int port),
  47                 int fd, int fd_ctl, void *packet, int len, void *data, int port)
  48 {
  49         if (countq < MAXQLEN) {
  50                 struct packetqq *new=malloc(sizeof(struct packetqq));
  51                 void *packetcopy=malloc(len);
  52                 if (new != NULL && packetcopy != NULL && len > 0) {
  53                         countq++;
  54                         new->sender=sender;
  55                         new->fd=fd;
  56                         new->fd_ctl=fd_ctl;
  57                         memcpy(packetcopy,packet,len);
  58                         new->packet=packetcopy;
  59                         new->len=len;
  60                         new->data=data;
  61                         new->port=port;
  62                         new->times=TIMES;
  63                         new->next=NULL;
  64                         if (pqh==NULL) {
  65                                 gettimeofday(&last_try,NULL);
  66                                 packetq_timeout=TIMEOUT;
  67                                 pqh=pqt=new;
  68                         } else {
  69                                 pqt->next=new;
  70                                 pqt=new;
  71                         }
  72                 } else {
  73                         if (new != NULL) free(new);
  74                         if (packetcopy != NULL) free(packetcopy);
  75                 }
  76         }
  77 }
  78
  79 static struct packetqq *packetq_scantry(struct packetqq *h,struct packetqq **t,fd_set *fds)
  80 {
  81         if (h != NULL) {
  82                 int sendrv=!(FD_ISSET(h->fd,fds));
  83                 h->times--;
  84                 if ((sendrv && (sendrv=h->sender(h->fd,h->fd_ctl,h->packet,h->len,h->data,h->port)) == 0)   /*send OK*/
  85                                 || h->times<=0) { /*or max number of attempts reached*/
  86                         struct packetqq *next;
  87 #if 0
  88                         /* this error code is unreachable! (sendrv==0 here) */
  89                         if (sendrv != 0) {
  90                                 if (sendrv < 0)
  91                                         printlog(LOG_WARNING,"packetqueue port %d: %s",h->port,strerror(-sendrv));
  92                                 else
  93                                         printlog(LOG_WARNING,"packetqueue port %d: partial send (%d bytes lost)",h->port,sendrv);
  94                         }
  95 #endif
  96                         next=h->next;
  97                         countq--;
  98                         free(h->packet);
  99                         free(h);
 100                         return packetq_scantry(next,t,fds);
 101                 } else {
 102                         FD_SET(h->fd,fds);
 103                         h->next=packetq_scantry(h->next,t,fds);
 104                         if (h->next == NULL) *t=h;
 105                         return h;
 106                 }
 107         } else
 108                 return NULL;
 109 }
 110
 111 void packetq_try(void)
 112 {
 113         if (pqh != NULL) {
 114                 struct timeval this_try;
 115                 gettimeofday(&this_try,NULL);
 116                 packetq_timeout=TIMEOUT - ((this_try.tv_sec-last_try.tv_sec) * 1000 +
 117                                 (this_try.tv_usec-last_try.tv_usec) / 1000);
 118                 if (packetq_timeout <= 0) {
 119                         fd_set fds;
 120                         FD_ZERO(&fds);
 121                         pqh=packetq_scantry(pqh,&pqt,&fds);
 122                         if (pqh != NULL) {
 123                                 gettimeofday(&last_try,NULL);
 124                                 packetq_timeout=TIMEOUT;
 125                         } else
 126                                 packetq_timeout = -1;
 127                 }
 128         }
 129 }
 130
 131 static struct packetqq *packetq_scandelfd(int fd,struct packetqq *h,struct packetqq **t)
 132 {
 133         if (h != NULL) {
 134                 if (fd == h->fd) {
 135                         struct packetqq *next=h->next;
 136                         countq--;
 137                         free(h->packet);
 138                         free(h);
 139                         return packetq_scandelfd(fd,next,t);
 140                 } else {
 141                         h->next=packetq_scandelfd(fd,h->next,t);
 142                         if (h->next == NULL) *t=h;
 143                         return h;
 144                 }
 145         } else
 146                 return NULL;
 147 }
 148
 149 void packetq_delfd(int fd)
 150 {
 151         pqh=packetq_scandelfd(fd,pqh,&pqt);
 152         if (pqh == NULL)
 153                 packetq_timeout = -1;
 154 }
 155
 156 int packetq_count()
 157 {
 158         return countq;
 159 }
 160 #endif