Major Description
In mod_python 2.7.11, the code for handling the PythonAutoReload directive was:
static const char *directive_PythonAutoReload(cmd_parms *cmd,
void *mconfig, int val) {
if (val)
return python_directive(cmd, mconfig, "PythonAutoReload", "1");
else
return python_directive(cmd, mconfig, "PythonAutoReload", "0");
}
Thus, if PythonAutoReload was set to "Off", the config table object was loaded with PythonAutoReload set to "0".
In mod_python 3.X at some point, it was changed to:
static const char *python_directive_flag(void * mconfig,
char *key, int val)
{
py_config *conf;
conf = (py_config *) mconfig;
if (val)
{ apr_table_set(conf->directives, key, "1"); }else { apr_table_unset(conf->directives, key); }
return NULL;
}
static const char *directive_PythonAutoReload(cmd_parms *cmd,
void *mconfig, int val) {
const char *rc = python_directive_flag(mconfig, "PythonAutoReload", val);
if (!rc) { py_config *conf = ap_get_module_config(cmd->server->module_config, &python_module); return python_directive_flag(conf, "PythonAutoReload", val); }
return rc;
}
Since that change, when PythonAutoReload was set ot "Off", no "0" value entry was added to the config table object, instead, if there was an existing entry it was removed. The removal would come into play when the option was set to "On" at global scope in main Apache configuration and then set to "Off" in a .htaccess file or other lesser scope such as a Directory directive.
The end result was that there was only an entry for PythonAutoReload in the config table object when it was set. When it existed, its value was "1".
The problem now is that the code which checks for PythonAutoReload in mod_python.apache module uses:
module = import_module(module_name,
autoreload=int(config.get("PythonAutoReload", 1)),
log=debug)
That is, if the PythonAutoReload option doesn't exist in the config table object, it defaults to the auto reload feature being turned On.
Thus, if PythonAutoReload is set to "On" in the configuration files, the Python code will find the value "1" and thus auto reload will be enabled. Because of the C code changes above though, when PythonAutoReload is set to "Off" in the config, no entry is put in the config table object at all and because the Python code can't find it, it defaults to using "1" with the result that auto reload will again be on.
In other words, it isn't possible to turn the feature off through the Apache configuration directive.
One solution is to change python_directive_flag() function to take an additional argument whereby it can be specified that "0" should be set for the value instead of the value being removed. Thus:
static const char *python_directive_flag(void * mconfig,
char *key, int val, int set)
{
py_config *conf;
conf = (py_config *) mconfig;
if (val) { apr_table_set(conf->directives, key, "1"); }
else {
if (set)
else
{ apr_table_unset(conf->directives, key); }}
return NULL;
}
All calls to this function except for PythonAutoReload case should supply "0" for additional argument, with "1" being supplied for PythonAutoReload case.
One can't just always set it to "0", as other code in mod_python.c uses the fact that an option exists to mean it is set. Ie., it doesn't check the value, thus setting it to "0" will cause that code to think the option used in that case (PythonInterpPerDirectory, PythonInterpPerDirective) is set to on when it isn't, thus causing that to stop working correctly.