Breaks configfiles! Major refactoring of i3status, see below

We finally switched to libconfuse for a configuration file format
which does not require much work for the programmer nor for the user.
Plus, it avoids the Not-Invented-Here syndrome of yet another config
file format.

Furthermore, as a consequence of providing format strings for every
"module" (ipv6, wireless, …), we directly print the output and thus
we needed to drop support for wmii. This allowed us to get rid of
quite some complexity.

Documentation about the new configuration file and options will
follow. This commit is the beginning of what will be i3status v2.0.

1 files changed, 99 insertions, 0 deletions

diff --git a/src/print_ipv6_addr.c b/src/print_ipv6_addr.c
new file mode 100644
index 0000000..fcb2df8
--- /dev/null
+++ b/src/print_ipv6_addr.c
@@ -0,0 +1,99 @@
+// vim:ts=8:expandtab
+#include <stdio.h>
+#include <unistd.h>
+#include <stdlib.h>
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <netdb.h>
+#include <string.h>
+#include <arpa/inet.h>
+
+/*
+ * Returns the IPv6 address with which you have connectivity at the moment.
+ *
+ */
+static void print_ipv6_addr() {
+        static char buf[INET6_ADDRSTRLEN+1];
+        struct addrinfo hints;
+        struct addrinfo *result, *resp;
+        int fd;
+
+        memset(&hints, 0, sizeof(struct addrinfo));
+        hints.ai_family = AF_INET6;
+
+        /* We resolve the K root server to get a public IPv6 address. You can
+         * replace this with any other host which has an AAAA record, but the
+         * K root server is a pretty safe bet. */
+        if (getaddrinfo("k.root-servers.net", "domain", &hints, &result) != 0) {
+                /* We don’t display the error here because most
+                 * likely, there just is no connectivity.
+                 * Thus, don’t spam the user’s console. */
+                printf("no IPv6");
+                return;
+        }
+
+        for (resp = result; resp != NULL; resp = resp->ai_next) {
+                if ((fd = socket(resp->ai_family, SOCK_DGRAM, 0)) == -1) {
+                        perror("socket()");
+                        continue;
+                }
+
+                /* Since the socket was created with SOCK_DGRAM, this is
+                 * actually not establishing a connection or generating
+                 * any other network traffic. Instead, as a side-effect,
+                 * it saves the local address with which packets would
+                 * be sent to the destination. */
+                if (connect(fd, resp->ai_addr, resp->ai_addrlen) == -1) {
+                        /* We don’t display the error here because most
+                         * likely, there just is no IPv6 connectivity.
+                         * Thus, don’t spam the user’s console but just
+                         * try the next address. */
+                        (void)close(fd);
+                        continue;
+                }
+
+                struct sockaddr_storage local;
+                socklen_t local_len = sizeof(struct sockaddr_storage);
+                if (getsockname(fd, (struct sockaddr*)&local, &local_len) == -1) {
+                        perror("getsockname()");
+                        (void)close(fd);
+                        printf("no IPv6");
+                        return;
+                }
+
+                (void)close(fd);
+
+                memset(buf, 0, INET6_ADDRSTRLEN + 1);
+                int ret;
+                if ((ret = getnameinfo((struct sockaddr*)&local, local_len,
+                                       buf, sizeof(buf), NULL, 0,
+                                       NI_NUMERICHOST)) != 0) {
+                        fprintf(stderr, "getnameinfo(): %s\n", gai_strerror(ret));
+                        printf("no IPv6");
+                        return;
+                }
+
+                free(result);
+                printf("%s", buf);
+                return;
+        }
+
+        free(result);
+        printf("no IPv6");
+}
+
+void print_ipv6_info(const char *format) {
+        const char *walk;
+
+        for (walk = format; *walk != '\0'; walk++) {
+                if (*walk != '%') {
+                        putchar(*walk);
+                        continue;
+                }
+
+                if (strncmp(walk+1, "ip", strlen("ip")) == 0) {
+                        print_ipv6_addr();
+                        walk += strlen("ip");
+                }
+        }
+}