Fix crash when a file has a large (year 10,000+) mtime.

https://bugzilla.redhat.com/show_bug.cgi?id=1893725
https://github.com/emikulic/darkhttpd/issues/21

darkhttpd.c

@@ -1301,8 +1301,9 @@ static void logencode(const char *src, char *dest) {
 static char *clf_date(char *dest, const time_t when) {
     time_t when_copy = when;
     if (strftime(dest, CLF_DATE_LEN,
-                 "[%d/%b/%Y:%H:%M:%S %z]", localtime(&when_copy)) == 0)
+                 "[%d/%b/%Y:%H:%M:%S %z]", localtime(&when_copy)) == 0) {
-        errx(1, "strftime() failed [%s]", dest);
+        dest[0] = 0;
+    }
     return dest;
 }
 
@@ -1456,8 +1457,9 @@ static void poll_check_timeout(struct connection *conn) {
 static char *rfc1123_date(char *dest, const time_t when) {
     time_t when_copy = when;
     if (strftime(dest, DATE_LEN,
-                 "%a, %d %b %Y %H:%M:%S GMT", gmtime(&when_copy)) == 0)
+                 "%a, %d %b %Y %H:%M:%S GMT", gmtime(&when_copy)) == 0) {
-        errx(1, "strftime() failed [%s]", dest);
+        dest[0] = 0;
+    }
     return dest;
 }
 

devel/test.py

@@ -6,6 +6,7 @@ import signal
 import re
 import os
 import random
+import time
 
 WWWROOT = "tmp.httpd.tests"
 
@@ -470,6 +471,24 @@ class TestLargeFile2G(TestHelper):
 class TestLargeFile4G(TestLargeFile2G):
     BOUNDARY = 1<<32
 
+class TestLargeMtime(TestHelper):
+    def setUp(self):
+        self.url = '/large_mtime'
+        self.fn = WWWROOT + self.url
+        with open(self.fn, 'wb') as f:
+            f.write(b'x')
+        # A timestamp in the year 10,000
+        t = int(time.mktime((10000,3,14,1,2,3,0,0,-1)))
+        os.utime(self.fn, (t, t))
+
+    def tearDown(self):
+        os.unlink(self.fn)
+
+    def test_file_get(self):
+        resp = self.get(self.url)
+        status, hdrs, body = parse(resp)
+        self.assertContains(status, "200 OK")
+
 if __name__ == '__main__':
     setUpModule()
     unittest.main()