Fix #473: handle log_wrap_size of 0

Setting log_wrap_size to 0 is supposed to disable log rotation, but
logger_std_h requires max_no_bytes to be set to the atom infinity for
this case. Adjust yaws_log to handle size 0 correctly. Add a new test
to gconf_SUITE that covers this case.

Author: vinoski

src/yaws_log.erl

@@ -401,8 +401,9 @@ code_change(_OldVsn, Data, _Extra) ->
 %%%----------------------------------------------------------------------
 report_logger_config(File, RotateSize) ->
     RotateConf =
-        case is_integer(RotateSize) of
-            true ->
+        case RotateSize of
+            0 -> #{max_no_bytes => infinity};
+            I when is_integer(I), I > 0 ->
                 #{
                   max_no_bytes => RotateSize,
                   max_no_files => 2

testsuite/gconf_SUITE.erl

@@ -8,7 +8,8 @@ all() ->
     [
      setup_default_gconf,
      set_gc_flags,
-     setup_mime_types_info
+     setup_mime_types_info,
+     log_wrap_size_zero
     ].
 
 groups() ->
@@ -28,9 +29,23 @@ init_per_group(_Group, Config) ->
 end_per_group(_Group, _Config) ->
     ok.
 
+init_per_testcase(log_wrap_size_zero, Config) ->
+    WWW = filename:join(?tempdir(?MODULE), "www"),
+    ok = testsuite:create_dir(WWW),
+    Id    = "testsuite-server",
+    YConf = filename:join(?tempdir(?MODULE), "yaws.conf"),
+    application:load(yaws),
+    application:set_env(yaws, id,   Id),
+    application:set_env(yaws, conf, YConf),
+    ok = yaws:start(),
+    [{yaws_id, Id}, {yaws_config, YConf} | Config];
 init_per_testcase(_Test, Config) ->
     Config.
 
+end_per_testcase(log_wrap_size_zero, _Config) ->
+    ok = application:stop(yaws),
+    ok = application:unload(yaws),
+    ok;
 end_per_testcase(_Test, _Config) ->
     ok.
 
@@ -104,6 +119,12 @@ setup_mime_types_info(_Config) ->
     ?assertEqual("/etc/mime.types", MI),
     ok.
 
+log_wrap_size_zero(_Config) ->
+    %% Nothing to do. If we get here, init succeeded, which means the
+    %% log_wrap_size configuration value of 0 was accepted. See bug
+    %% #473.
+    ok.
+
 %% =======================================================================
 get_gconf_attr(Name, GConf) ->
     Fun = list_to_atom("gconf_" ++ atom_to_list(Name)),

testsuite/gconf_SUITE_data/templates/yaws.conf

@@ -0,0 +1,16 @@
+logdir = $logdir$
+
+ebin_dir = $data_builddir$
+
+# Verify 0 as a valid log_wrap_size (bug #473)
+log_wrap_size                  = 0
+log_resolve_hostname           = false
+fail_on_bind_err               = true
+pick_first_virthost_on_nomatch = true
+keepalive_timeout              = 10000
+
+<server localhost>
+        listen = 127.0.0.1
+        port = $yaws_port1$
+        docroot = $tempdir$/www
+</server>