rework to separate out python module

Remove the magic from the magic _db* modules.
Combine as one 'devsup._dbapi'.

libpyDevSup exists only to bootstrap python
interpreter in IOCs.

pyIocApp/Makefile

@@ -10,6 +10,25 @@ include $(TOP)/configure/CONFIG_PY
 #=============================
 # Build the IOC application
 
+USR_CPPFLAGS += -I$(TOP)/devsupApp/src
+
+LIBRARY = pyDevSup$(PY_LD_VER)
+
+SHRLIB_VERSION = 0
+
+DBD += pyDevSup.dbd
+
+pyDevSup$(PY_LD_VER)_SYS_LIBS += python$(PY_LD_VER)
+
+pyDevSup$(PY_LD_VER)_LIBS += $(EPICS_BASE_IOC_LIBS)
+
+setup_CPPFLAGS += -DXEPICS_ARCH=\"$(T_A)\"
+setup_CPPFLAGS += -DXPYDEV_BASE=\"$(abspath $(INSTALL_LOCATION))\"
+setup_CPPFLAGS += -DXEPICS_BASE=\"$(EPICS_BASE)\"
+setup_CPPFLAGS += -DPYDIR=\"python$(PY_VER)\"
+
+pyDevSup$(PY_LD_VER)_SRCS += setup.c
+
 PROD_IOC = softIocPy$(PY_VER)
 PRODNAME = $(addsuffix $(EXE),$(PROD))
 

pyIocApp/pyDevSup.dbd

@@ -0,0 +1 @@
+registrar(pySetupReg)

pyIocApp/setup.c

@@ -0,0 +1,133 @@
+/* Global interpreter setup
+ */
+
+/* python has its own ideas about which version to support */
+#undef _POSIX_C_SOURCE
+#undef _XOPEN_SOURCE
+
+#include <Python.h>
+#ifdef HAVE_NUMPY
+#include <numpy/ndarrayobject.h>
+#endif
+
+#include <stdio.h>
+
+#include <epicsVersion.h>
+#include <dbCommon.h>
+#include <dbAccess.h>
+#include <dbStaticLib.h>
+#include <dbScan.h>
+#include <initHooks.h>
+#include <epicsThread.h>
+#include <epicsExit.h>
+#include <alarm.h>
+
+#include "pydevsup.h"
+
+static void cleanupPy(void *junk)
+{
+    PyThreadState *state = PyGILState_GetThisThreadState();
+
+    PyEval_RestoreThread(state);
+
+    /* special "fake" hook for shutdown */
+    //pyhook((initHookState)9999);
+
+    Py_Finalize(); // calls python atexit hooks
+}
+
+static void extendPath(PyObject *list,
+                       const char *base,
+                       const char *archdir)
+{
+    PyObject *mod, *ret;
+
+    mod = PyImport_ImportModule("os.path");
+    if(!mod)
+        return;
+
+    ret = PyObject_CallMethod(mod, "join", "sss", base, PYDIR, archdir);
+    if(ret && !PySequence_Contains(list, ret)) {
+        PyList_Insert(list, 0, ret);
+    }
+    Py_XDECREF(ret);
+    Py_DECREF(mod);
+    if(PyErr_Occurred()) {
+        PyErr_Print();
+        PyErr_Clear();
+    }
+}
+
+static void insertDefaultPath(PyObject *list)
+{
+    const char *basedir, *pydevdir, *top, *arch;
+
+    basedir = getenv("EPICS_BASE");
+    if(!basedir)
+        basedir = XEPICS_BASE;
+    pydevdir = getenv("PYDEV_BASE");
+    if(!pydevdir)
+        pydevdir = XPYDEV_BASE;
+    top = getenv("TOP");
+    arch = getenv("ARCH");
+    if(!arch)
+        arch = XEPICS_ARCH;
+
+    assert(PyList_Check(list));
+    assert(PySequence_Check(list));
+    extendPath(list, basedir, arch);
+    extendPath(list, pydevdir, arch);
+    if(top)
+        extendPath(list, top, arch);
+}
+
+static void setupPyPath(void)
+{
+    PyObject *mod, *path = NULL;
+
+    mod = PyImport_ImportModule("sys");
+    if(mod)
+        path = PyObject_GetAttrString(mod, "path");
+    Py_XDECREF(mod);
+
+    if(path) {
+        PyObject *cur;
+        char cwd[PATH_MAX];
+
+        insertDefaultPath(path);
+
+        /* prepend current directory */
+        if(getcwd(cwd, sizeof(cwd)-1)) {
+            cwd[sizeof(cwd)-1] = '\0';
+            cur = PyString_FromString(cwd);
+            if(cur)
+                PyList_Insert(path, 0, cur);
+            Py_XDECREF(cur);
+        }
+    }
+    Py_XDECREF(path);
+}
+
+static void pySetupReg(void)
+{
+    PyGILState_STATE state;
+
+    Py_Initialize();
+    PyEval_InitThreads();
+
+    setupPyPath();
+
+    if(PyRun_SimpleString("import devsup\n"
+                          "devsup._init(True)\n"
+    )) {
+        PyErr_Print();
+        PyErr_Clear();
+    }
+
+    (void)PyEval_SaveThread();
+
+    epicsAtExit(&cleanupPy, NULL);
+}
+
+#include <epicsExport.h>
+epicsExportRegistrar(pySetupReg);