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