X-Git-Url: http://git.meshlink.io/?a=blobdiff_plain;ds=sidebyside;f=tests%2Fdns-spin-test.c;fp=tests%2Fdns-spin-test.c;h=51af02d1df66f89fd322712b95f30d3ec757c6ba;hb=5133886fe11d7650bc89b46746731ca2eab2185d;hp=0000000000000000000000000000000000000000;hpb=3b898d826ec5e97f287481ea1612483e6f3cc066;p=catta

diff --git a/tests/dns-spin-test.c b/tests/dns-spin-test.c
new file mode 100644
index 0000000..51af02d
--- /dev/null
+++ b/tests/dns-spin-test.c
@@ -0,0 +1,122 @@
+/***
+  This file is part of avahi.
+
+  avahi is free software; you can redistribute it and/or modify it
+  under the terms of the GNU Lesser General Public License as
+  published by the Free Software Foundation; either version 2.1 of the
+  License, or (at your option) any later version.
+
+  avahi is distributed in the hope that it will be useful, but WITHOUT
+  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+  or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General
+  Public License for more details.
+
+  You should have received a copy of the GNU Lesser General Public
+  License along with avahi; if not, write to the Free Software
+  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
+  USA.
+***/
+
+/* Regression test for Avahi bug #84.
+ * This program tests whether the avahi_dns_packet_consume_name function
+ * returns (rather than spinning forever). For a function as simple as
+ * avahi_dns_packet_consume_name, we assume that 1 second of CPU time ≈ forever
+ */
+
+#ifdef HAVE_CONFIG_H
+# include <config.h>
+#endif
+
+#include <string.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <signal.h>
+#include <sys/time.h>
+
+#include <avahi/dns.h>
+
+#define MAX_CPU_SECONDS 1
+
+#define TEST_NAME "dns-spin-test"
+
+static void fail(const char *fmt, ...) __attribute__((format(printf, 1, 2), noreturn));
+static void unresolved(const char *fmt, ...) __attribute__((format(printf, 1, 2), noreturn));
+static void stdlib_fail(const char *msg) __attribute__((noreturn));
+static void handle(int sig) __attribute__((noreturn));
+
+void stdlib_fail(const char *msg) {
+    perror(msg);
+
+    printf("UNRESOLVED: " TEST_NAME " (stdlib failure)\n");
+
+    exit(77);
+}
+
+void unresolved(const char *fmt, ...) {
+    va_list ap;
+
+    printf("UNRESOLVED: " TEST_NAME ": ");
+    va_start(ap, fmt);
+    vprintf(fmt, ap);
+    va_end(ap);
+    printf("\n");
+
+    exit(77);
+}
+
+void fail(const char *fmt, ...) {
+    va_list ap;
+
+    va_start(ap, fmt);
+    vprintf(fmt, ap);
+    va_end(ap);
+    printf("\n");
+
+    exit(EXIT_FAILURE);
+}
+
+void handle(AVAHI_GCC_UNUSED int sig) {
+    fail("Interrupted after %d second of CPU time", MAX_CPU_SECONDS);
+}
+
+#define TRY_EXCEPT(cmd, badresult) \
+    do { \
+        if ((cmd) == (badresult)) \
+            unresolved("%s returned %s", #cmd, #badresult); \
+    } while (0)
+
+int main(AVAHI_GCC_UNUSED int argc, AVAHI_GCC_UNUSED char *argv[]) {
+    struct itimerval itval;
+    AvahiDnsPacket *packet;
+    char name[512];
+    int ret;
+    uint8_t badrr[] = {
+        0xC0, AVAHI_DNS_PACKET_HEADER_SIZE, /* self-referential QNAME pointer */
+        0, 1, /* QTYPE A (host addr) */
+        0, 1, /* QCLASS IN (internet/ipv4) */
+    };
+
+    if (signal(SIGVTALRM, handle) == SIG_ERR)
+        stdlib_fail("signal(SIGVTALRM)");
+
+    memset(&itval, 0, sizeof(itval));
+    itval.it_value.tv_sec = MAX_CPU_SECONDS;
+
+    if (setitimer(ITIMER_VIRTUAL, &itval, NULL) == -1)
+        stdlib_fail("setitimer()");
+
+    TRY_EXCEPT(packet = avahi_dns_packet_new_query(512), NULL);
+    TRY_EXCEPT(avahi_dns_packet_append_bytes(packet, badrr, sizeof(badrr)), NULL);
+
+    /* This is expected to fail (if it returns) */
+    ret = avahi_dns_packet_consume_name(packet, name, sizeof(name));
+
+    if (ret != -1)
+        fail("avahi_dns_packet_consume_name() returned %d; -1 was expected", ret);
+
+    return EXIT_SUCCESS;
+}
+
+/* vim:ts=4:sw=4:et
+ */