Introducing python virtualenv configuration.

New parameter 'home' for python application allows to configure
application-specific virtualenv path.

This closes #15 issue on GitHub.

src/nxt_application.h

@@ -34,6 +34,7 @@ typedef struct nxt_common_app_conf_s nxt_common_app_conf_t;
 
 
 typedef struct {
+    char       *home;
     nxt_str_t  path;
     nxt_str_t  module;
 } nxt_python_app_conf_t;

src/nxt_conf_validation.c

@@ -118,6 +118,11 @@ static nxt_conf_vldt_object_t  nxt_conf_vldt_python_members[] = {
       NULL,
       NULL },
 
+    { nxt_string("home"),
+      NXT_CONF_STRING,
+      NULL,
+      NULL },
+
     { nxt_string("path"),
       NXT_CONF_STRING,
       NULL,
@@ -545,3 +550,5 @@ nxt_conf_vldt_group(nxt_conf_validation_t *vldt, char *group)
 
     return NXT_ERROR;
 }
+
+

src/nxt_main_process.c

@@ -120,6 +120,12 @@ static nxt_conf_map_t  nxt_common_app_conf[] = {
         offsetof(nxt_common_app_conf_t, workers),
     },
 
+    {
+        nxt_string("home"),
+        NXT_CONF_MAP_CSTRZ,
+        offsetof(nxt_common_app_conf_t, u.python.home),
+    },
+
     {
         nxt_string("path"),
         NXT_CONF_MAP_STR,

src/nxt_python_wsgi.c

@@ -177,6 +177,12 @@ static PyObject           *nxt_py_application;
 static PyObject           *nxt_py_start_resp_obj;
 static PyObject           *nxt_py_environ_ptyp;
 
+#if PY_MAJOR_VERSION == 3
+static wchar_t            *nxt_py_home;
+#else
+static char               *nxt_py_home;
+#endif
+
 static nxt_python_run_ctx_t  *nxt_python_run_ctx;
 
 
@@ -194,6 +200,26 @@ nxt_python_init(nxt_task_t *task, nxt_common_app_conf_t *conf)
         return NXT_ERROR;
     }
 
+    if (c->home != NULL) {
+        size_t  len;
+
+        len = nxt_strlen(c->home);
+
+        nxt_py_home = nxt_malloc(sizeof(*nxt_py_home) * (len + 1));
+        if (nxt_slow_path(nxt_py_home == NULL)) {
+            nxt_log_emerg(task->log, "Failed to allocate buffer for home path");
+            return NXT_ERROR;
+        }
+
+#if PY_MAJOR_VERSION == 3
+        mbstowcs(nxt_py_home, c->home, len + 1);
+#else
+        nxt_memcpy(nxt_py_home, c->home, len + 1);
+#endif
+
+        Py_SetPythonHome(nxt_py_home);
+    }
+
     Py_InitializeEx(0);
 
     obj = NULL;
@@ -301,6 +327,10 @@ fail:
     Py_XDECREF(obj);
     Py_XDECREF(module);
 
+    if (nxt_py_home != NULL) {
+        nxt_free(nxt_py_home);
+    }
+
     return NXT_ERROR;
 }