From 35b28230e17a68db48f3b5fc91d2eec0c80e048c Mon Sep 17 00:00:00 2001 From: daniel Date: Sat, 26 Jan 2013 13:10:08 +0900 Subject: Add a "hack" to report back to the vxi11 service code when a link dies. It's a hack because linux/glibc's RPC implementation doesn't seem to have the ability to set a recv error callback. The hack is to add an extra event to the events poll'd.. that event tells us if the socket died. --- libvxi11client/libvxi11client.c | 6 +++-- vxi11_server.c | 39 +++++++++++++++++++++-------- vxi11_server.h | 1 + vxi11_svc.c | 55 +++++++++++++++++++++++++++++++++++++++-- 4 files changed, 87 insertions(+), 14 deletions(-) diff --git a/libvxi11client/libvxi11client.c b/libvxi11client/libvxi11client.c index 743168f..0e01809 100644 --- a/libvxi11client/libvxi11client.c +++ b/libvxi11client/libvxi11client.c @@ -214,8 +214,10 @@ int vxi11_read(VXI11Context* context, char* buffer, unsigned int bufferlen, bool #ifdef DEBUG printf("Got \"%s\" from server\n", resp->data.data_val); #endif - if (buffer != NULL) - strncpy(buffer, resp->data.data_val, (bufferlen < resp->data.data_len ? bufferlen : resp->data.data_len)); + if (buffer != NULL && resp->data.data_val != NULL) { + int lengthtocopy = ((bufferlen - 1) < resp->data.data_len ? (bufferlen - 1) : resp->data.data_len); + strncpy(buffer, resp->data.data_val, lengthtocopy); + } #ifdef DEBUG else printf("Supplied buffer is null!\n"); diff --git a/vxi11_server.c b/vxi11_server.c index ae8317f..4185542 100644 --- a/vxi11_server.c +++ b/vxi11_server.c @@ -47,6 +47,7 @@ static gchar* inthandler = NULL; #define LINKLONGSINCEDEADTIMEOUT ((10 * 60) * 1000000) // ten minutes typedef struct { int lid; + int sock; GTimeVal lastactivity; } ActiveLink; @@ -66,6 +67,29 @@ static bool isValidLink(int linkid) { return links[linkid] != NULL; } +static void freelink(ActiveLink* link) { + links[link->lid] = NULL; + globals.Remote.vxi_connections--; +#ifdef DEBUG + printf("link %d destroyed, %d active links\n", link->lid, globals.Remote.vxi_connections); +#endif + g_free(link); +} + +void vxi11_deadsocketcallback(int socket) { + int linkid; + for (linkid = 0; linkid < SIZEOFARRAY(links); linkid++) { + if (links[linkid] != NULL) { + if (links[linkid]->sock == socket) { +#ifdef DEBUG + printf("Freeing link %d, socket died\n", linkid); +#endif + freelink(links[linkid]); + } + } + } +} + // test if a link has expired, this is to avoid dead locks static bool linkexpired(ActiveLink* link) { GTimeVal cutoff; @@ -75,9 +99,7 @@ static bool linkexpired(ActiveLink* link) { #ifdef DEBUG printf("Link %d is apparently dead, removing\n", link->lid); #endif - links[link->lid] = NULL; - g_free(link); - globals.Remote.vxi_connections--; + freelink(link); return true; } else @@ -171,10 +193,11 @@ create_link_1_svc(Create_LinkParms *argp, struct svc_req *rqstp) { } g_assert(linkid != SIZEOFARRAY(links)); link->lid = linkid; + link->sock = rqstp->rq_xprt->xp_sock; touchlink(linkid); globals.Remote.vxi_connections++; #ifdef DEBUG - printf("created link %d, %d active links\n", linkid, globals.Remote.vxi_connections); + printf("created link %d(socket %d), %d active links\n", linkid, link->sock, globals.Remote.vxi_connections); #endif struct sockaddr_in sin; @@ -184,6 +207,7 @@ create_link_1_svc(Create_LinkParms *argp, struct svc_req *rqstp) { result.abortPort = ntohs(sin.sin_port); result.maxRecvSize = MAXRECV; result.lid = linkid; + } } return &result; @@ -468,13 +492,8 @@ destroy_link_1_svc(Device_Link *argp, struct svc_req *rqstp) { unlock(); } - globals.Remote.vxi_connections--; -#ifdef DEBUG - printf("link %d destroyed, %d active links\n", lid, globals.Remote.vxi_connections); -#endif + freelink(links[lid]); result.error = 0; - g_free(links[lid]); - links[lid] = NULL; } return &result; diff --git a/vxi11_server.h b/vxi11_server.h index f682f58..5c4450d 100644 --- a/vxi11_server.h +++ b/vxi11_server.h @@ -1 +1,2 @@ void vxi11_fireinterrupt(void); +void vxi11_deadsocketcallback(int socket); diff --git a/vxi11_svc.c b/vxi11_svc.c index edc4212..e5c4b38 100644 --- a/vxi11_svc.c +++ b/vxi11_svc.c @@ -1,12 +1,18 @@ +#define _GNU_SOURCE + #include "vxi11.h" +#include "vxi11_server.h" #include #include #include #include #include +#include #include #include +#define VXI11_DEFAULT_TIMEOUT 1000 + #ifndef SIG_PF #define SIG_PF void(*)(int) #endif @@ -223,6 +229,51 @@ void vxi_main() { exit(1); } - svc_run(); - fprintf(stderr, "%s", "svc_run returned"); + int i, j; + struct pollfd *my_pollfd = NULL; + int last_max_pollfd = 0; + + while (1) { + int max_pollfd = svc_max_pollfd; + if (max_pollfd == 0 && svc_pollfd == NULL) + break; + + if (last_max_pollfd != max_pollfd) { + struct pollfd *new_pollfd = realloc(my_pollfd, sizeof(struct pollfd) * max_pollfd); + + if (new_pollfd == NULL) { + break; + } + + my_pollfd = new_pollfd; + last_max_pollfd = max_pollfd; + } + + for (i = 0; i < max_pollfd; ++i) { + my_pollfd[i].fd = svc_pollfd[i].fd; + my_pollfd[i].events = svc_pollfd[i].events | POLLRDHUP; // add the "socket is dead" event + my_pollfd[i].revents = 0; + } + + j = poll(my_pollfd, max_pollfd, VXI11_DEFAULT_TIMEOUT); + + for (i = 0; i < max_pollfd; i++) { + if (my_pollfd[i].revents & POLLRDHUP) + vxi11_deadsocketcallback(my_pollfd[i].fd); + } + + switch (j) { + case -1: + break; + case 0: + continue; + default: + svc_getreq_poll(my_pollfd, i); + continue; + } + break; + } + + //svc_run(); + //fprintf(stderr, "%s", "svc_run returned"); } -- cgit