Merge branch 'se/port_SUITE_env' into dev

* se/port_SUITE_env:
  fix open_port with many unset env vars
  allow open_port with env vars with trailing '=' on Windows

OTP-8701 se/port_SUITE_env

open_port/2 with the spawn and spawn_executable options can include an
{env,Env} option. In some cases unsetting variables would not work on Unix
(typically if more variables were unset than were actually present in the
environment).

3 files changed, 27 insertions, 10 deletions

diff --git a/erts/emulator/sys/unix/sys.c b/erts/emulator/sys/unix/sys.c
index 151fa06e8e..737ffd9f94 100644
--- a/erts/emulator/sys/unix/sys.c
+++ b/erts/emulator/sys/unix/sys.c
@@ -1328,10 +1328,18 @@ static char **build_unix_environment(char *block)
 	}
     }
 
-    for (j = 0; j < i; j++) {
+    for (j = 0; j < i; ) {
         size_t last = strlen(cpp[j])-1;
 	if (cpp[j][last] == '=' && strchr(cpp[j], '=') == cpp[j]+last) {
 	    cpp[j] = cpp[--len];
+	    if (len < i) {
+		i--;
+	    } else {
+		j++;
+	    }
+	}
+	else {
+	    j++;
 	}
     }
 
diff --git a/erts/emulator/sys/win32/sys_env.c b/erts/emulator/sys/win32/sys_env.c
index ac4be3f316..02c8433a10 100644
--- a/erts/emulator/sys/win32/sys_env.c
+++ b/erts/emulator/sys/win32/sys_env.c
@@ -1,19 +1,19 @@
 /*
  * %CopyrightBegin%
- * 
- * Copyright Ericsson AB 2002-2009. All Rights Reserved.
- * 
+ *
+ * Copyright Ericsson AB 2002-2010. All Rights Reserved.
+ *
  * The contents of this file are subject to the Erlang Public License,
  * Version 1.1, (the "License"); you may not use this file except in
  * compliance with the License. You should have received a copy of the
  * Erlang Public License along with this software. If not, it can be
  * retrieved online at http://www.erlang.org/.
- * 
+ *
  * Software distributed under the License is distributed on an "AS IS"
  * basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
  * the License for the specific language governing rights and limitations
  * under the License.
- * 
+ *
  * %CopyrightEnd%
  */
 
@@ -145,15 +145,17 @@ merge_environment(char *old, char *add)
     for(j = 0; a_arg[j] != NULL; ++j){
 	char **tmp;
 	char *current = a_arg[j];
+	char *eq_p = strchr(current,'=');
+	int unset = (eq_p!=NULL && eq_p[1]=='\0');
 
 	if ((tmp = find_arg(c_arg, current)) != NULL) {
-	    if (current[strlen(current)-1] != '=') {
+	    if (!unset) {
 		*tmp = current;
 	    } else {
 		*tmp = c_arg[--i];
 		c_arg[i] = NULL;
 	    }
-	} else if (current[strlen(current)-1] != '=') {
+	} else if (!unset) {
 	    c_arg[i++] = current;
 	    c_arg[i] = NULL;
 	}
diff --git a/erts/emulator/test/port_SUITE.erl b/erts/emulator/test/port_SUITE.erl
index 66aff307a3..77fa75b78f 100644
--- a/erts/emulator/test/port_SUITE.erl
+++ b/erts/emulator/test/port_SUITE.erl
@@ -878,13 +878,20 @@ env2(Config) ->
 			    "nisse" = os:getenv(Long)
 		    end),
 
-
+    
     ?line env_slave(Temp, [{"must_define_something","some_value"},
-			   {"certainly_not_existing",false},
+			    {"certainly_not_existing",false},
                            {"ends_with_equal", "value="},
 			   {Long,false},
 			   {"glurf","a glorfy string"}]),
 
+    %% A lot of non existing variables (mingled with existing)
+    NotExistingList = [{lists:flatten(io_lib:format("V~p_not_existing",[X])),false} 
+                        ||  X <- lists:seq(1,150)],
+    ExistingList = [{lists:flatten(io_lib:format("V~p_existing",[X])),"a_value"} 
+                        ||  X <- lists:seq(1,150)],
+    ?line env_slave(Temp, lists:sort(ExistingList ++ NotExistingList)),
+
     ?line test_server:timetrap_cancel(Dog),
     ok.