Add an event loop.

Split client.c into smaller files and functions and
recode around the event loop.
Add multiple interface support using the new event loop.
Document changes and outstanding bugs.

1 files changed, 65 insertions, 20 deletions

diff --git a/if-linux.c b/if-linux.c
index afb0ea64..45b5b2b7 100644
--- a/if-linux.c
+++ b/if-linux.c
@@ -40,6 +40,7 @@
 #include <netpacket/packet.h>
 
 #include <errno.h>
+#include <ctype.h>
 #include <stddef.h>
 #include <stdio.h>
 #include <stdlib.h>
@@ -59,7 +60,7 @@
 #define BUFFERLEN 256
 
 int
-open_link_socket(struct interface *iface)
+open_link_socket(void)
 {
 	int fd;
 	struct sockaddr_nl nl;
@@ -72,16 +73,13 @@ open_link_socket(struct interface *iface)
 	if (bind(fd, (struct sockaddr *)&nl, sizeof(nl)) == -1)
 		return -1;
 	set_cloexec(fd);
-	if (iface->link_fd != -1)
-		close(iface->link_fd);
-	iface->link_fd = fd;
-	return 0;
+	return fd;
 }
 
 static int
 get_netlink(int fd, int flags,
-	    int (*callback)(struct nlmsghdr *, const char *),
-	    const char *ifname)
+	    int (*callback)(struct nlmsghdr *, const struct interface *),
+	    const struct interface *iface)
 {
 	char *buffer = NULL;
 	ssize_t bytes;
@@ -104,7 +102,7 @@ get_netlink(int fd, int flags,
 		     NLMSG_OK(nlm, (size_t)bytes);
 		     nlm = NLMSG_NEXT(nlm, bytes))
 		{
-			r = callback(nlm, ifname);
+			r = callback(nlm, iface);
 			if (r != 0)
 				goto eexit;
 		}
@@ -116,7 +114,7 @@ eexit:
 }
 
 static int
-err_netlink(struct nlmsghdr *nlm, _unused const char *ifname)
+err_netlink(struct nlmsghdr *nlm, _unused const struct interface *iface)
 {
 	struct nlmsgerr *err;
 	int l;
@@ -136,12 +134,13 @@ err_netlink(struct nlmsghdr *nlm, _unused const char *ifname)
 }
 
 static int
-link_netlink(struct nlmsghdr *nlm, const char *ifname)
+link_netlink(struct nlmsghdr *nlm, const struct interface *ifaces)
 {
 	int len;
 	struct rtattr *rta;
 	struct ifinfomsg *ifi;
 	char ifn[IF_NAMESIZE + 1];
+	const struct interface *iface;
 
 	if (nlm->nlmsg_type != RTM_NEWLINK && nlm->nlmsg_type != RTM_DELLINK)
 		return 0;
@@ -171,16 +170,16 @@ link_netlink(struct nlmsghdr *nlm, const char *ifname)
 		rta = RTA_NEXT(rta, len);
 	}
 
-	if (strncmp(ifname, ifn, sizeof(ifn)) == 0)
-		return 1;
+	for (iface = ifaces; iface; iface = iface->next)
+		if (strcmp(iface->name, ifn) == 0)
+			return 1;
 	return 0;
 }
 
 int
-link_changed(struct interface *iface)
+link_changed(int fd, const struct interface *iface)
 {
-	return get_netlink(iface->link_fd, MSG_DONTWAIT,
-			   &link_netlink, iface->name);
+	return get_netlink(fd, MSG_DONTWAIT, &link_netlink, iface);
 }
 
 static int
@@ -279,7 +278,7 @@ struct nlmr
 };
 
 int
-if_address(const char *ifname,
+if_address(const struct interface *iface,
 	   const struct in_addr *address, const struct in_addr *netmask,
 	   const struct in_addr *broadcast, int action)
 {
@@ -294,7 +293,7 @@ if_address(const char *ifname,
 		nlm->hdr.nlmsg_type = RTM_NEWADDR;
 	} else
 		nlm->hdr.nlmsg_type = RTM_DELADDR;
-	if (!(nlm->ifa.ifa_index = if_nametoindex(ifname))) {
+	if (!(nlm->ifa.ifa_index = if_nametoindex(iface->name))) {
 		free(nlm);
 		errno = ENODEV;
 		return -1;
@@ -303,7 +302,7 @@ if_address(const char *ifname,
 	nlm->ifa.ifa_prefixlen = inet_ntocidr(*netmask);
 	/* This creates the aliased interface */
 	add_attr_l(&nlm->hdr, sizeof(*nlm), IFA_LABEL,
-		   ifname, strlen(ifname) + 1);
+		   iface->name, strlen(iface->name) + 1);
 	add_attr_l(&nlm->hdr, sizeof(*nlm), IFA_LOCAL,
 		   &address->s_addr, sizeof(address->s_addr));
 	if (action >= 0)
@@ -317,7 +316,7 @@ if_address(const char *ifname,
 }
 
 int
-if_route(const char *ifname,
+if_route(const struct interface *iface,
 	 const struct in_addr *destination, const struct in_addr *netmask,
 	 const struct in_addr *gateway, int metric, int action)
 {
@@ -326,7 +325,7 @@ if_route(const char *ifname,
 	int retval = 0;
 
 
-	if (!(ifindex = if_nametoindex(ifname))) {
+	if (!(ifindex = if_nametoindex(iface->name))) {
 		errno = ENODEV;
 		return -1;
 	}
@@ -370,3 +369,49 @@ if_route(const char *ifname,
 	free(nlm);
 	return retval;
 }
+
+struct interface *
+discover_interfaces(int argc, char * const *argv)
+{
+	FILE *f;
+	char *buffer = NULL, *p;
+	size_t len = 0, ln = 0, n;
+	int i, s;
+	struct interface *ifaces = NULL, *ifp, *ifl;
+
+	if ((f = fopen("/proc/net/dev", "r"))) {
+		while (get_line(&buffer, &len, f)) {
+			if (++ln < 2)
+				continue;
+			p = buffer;
+			while (isspace((unsigned int)*p))
+				p++;
+			n = strcspn(p, ": \t");
+			p[n]= '\0';
+			ifl = NULL;
+			for (ifp = ifaces; ifp; ifp = ifp->next) {
+				if (strcmp(ifp->name, p) == 0)
+					break;
+				ifl = ifp;
+			}
+			if (ifp)
+				continue;
+			if (argc > 0) {
+				for (i = 0; i < argc; i++)
+					if (strcmp(argv[i], p) == 0)
+						break;
+				if (i == argc)
+					continue;
+			}
+			if (ifp = init_interface(p)) {
+				if (ifl)
+					ifl->next =ifp; 
+				else
+					ifaces = ifp;
+			}
+		}
+		fclose(f);
+		free(buffer);
+	}
+	return ifaces;
+}