Better unix filesystem integration as documented here
[blender-staging.git] / source / blender / python / intern / bpy_interface.c
1 /**
2  * $Id:
3  *
4  * ***** BEGIN GPL LICENSE BLOCK *****
5  *
6  * This program is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU General Public License
8  * as published by the Free Software Foundation; either version 2
9  * of the License, or (at your option) any later version.
10  *
11  * This program is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14  * GNU General Public License for more details.
15  *
16  * You should have received a copy of the GNU General Public License
17  * along with this program; if not, write to the Free Software Foundation,
18  * Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
19  *
20  * Contributor(s): Michel Selten, Willian P. Germano, Stephen Swaney,
21  * Chris Keith, Chris Want, Ken Hughes, Campbell Barton
22  *
23  * ***** END GPL LICENSE BLOCK *****
24  */
25  
26 #include <stdio.h>
27 #include <stdlib.h>
28 #include <string.h>
29 #include <sys/stat.h>
30
31
32 /* grr, python redefines */
33 #ifdef _POSIX_C_SOURCE
34 #undef _POSIX_C_SOURCE
35 #endif
36
37 #include <Python.h>
38 #include "compile.h"            /* for the PyCodeObject */
39 #include "eval.h"               /* for PyEval_EvalCode */
40
41 #include "bpy_rna.h"
42 #include "bpy_operator.h"
43 #include "bpy_ui.h"
44 #include "bpy_util.h"
45
46 #ifndef WIN32
47 #include <dirent.h>
48 #else
49 #include "BLI_winstuff.h"
50 #endif
51
52 #include "DNA_anim_types.h"
53 #include "DNA_space_types.h"
54 #include "DNA_text_types.h"
55
56 #include "MEM_guardedalloc.h"
57
58 #include "BLI_util.h"
59 #include "BLI_storage.h"
60 #include "BLI_fileops.h"
61 #include "BLI_string.h"
62
63 #include "BKE_context.h"
64 #include "BKE_fcurve.h"
65 #include "BKE_text.h"
66
67 #include "BPY_extern.h"
68
69 #include "../generic/bpy_internal_import.h" // our own imports
70 /* external util modules */
71
72 #include "../generic/Mathutils.h"
73 #include "../generic/Geometry.h"
74 #include "../generic/BGL.h"
75
76
77 /* for internal use, when starting and ending python scripts */
78
79 /* incase a python script triggers another python call, stop bpy_context_clear from invalidating */
80 static int py_call_level= 0;
81
82
83 // only for tests
84 #define TIME_PY_RUN
85
86 #ifdef TIME_PY_RUN
87 #include "PIL_time.h"
88 static int              bpy_timer_count = 0;
89 static double   bpy_timer; /* time since python starts */
90 static double   bpy_timer_run; /* time for each python script run */
91 static double   bpy_timer_run_tot; /* accumulate python runs */
92 #endif
93
94 void bpy_context_set(bContext *C, PyGILState_STATE *gilstate)
95 {
96         py_call_level++;
97
98         if(gilstate)
99                 *gilstate = PyGILState_Ensure();
100
101         if(py_call_level==1) {
102
103                 BPY_update_modules(); /* can give really bad results if this isnt here */
104
105                 if(C) { // XXX - should always be true.
106                         BPy_SetContext(C);
107                         bpy_import_main_set(CTX_data_main(C));
108                 }
109                 else {
110                         fprintf(stderr, "ERROR: Python context called with a NULL Context. this should not happen!\n");
111                 }
112
113 #ifdef TIME_PY_RUN
114                 if(bpy_timer_count==0) {
115                         /* record time from the beginning */
116                         bpy_timer= PIL_check_seconds_timer();
117                         bpy_timer_run = bpy_timer_run_tot = 0.0;
118                 }
119                 bpy_timer_run= PIL_check_seconds_timer();
120
121
122                 bpy_timer_count++;
123 #endif
124         }
125 }
126
127 void bpy_context_clear(bContext *C, PyGILState_STATE *gilstate)
128 {
129         py_call_level--;
130
131         if(gilstate)
132                 PyGILState_Release(*gilstate);
133
134         if(py_call_level < 0) {
135                 fprintf(stderr, "ERROR: Python context internal state bug. this should not happen!\n");
136         }
137         else if(py_call_level==0) {
138                 // XXX - Calling classes currently wont store the context :\, cant set NULL because of this. but this is very flakey still.
139                 //BPy_SetContext(NULL);
140                 //bpy_import_main_set(NULL);
141
142 #ifdef TIME_PY_RUN
143                 bpy_timer_run_tot += PIL_check_seconds_timer() - bpy_timer_run;
144                 bpy_timer_count++;
145 #endif
146
147         }
148 }
149
150
151 void BPY_free_compiled_text( struct Text *text )
152 {
153         if( text->compiled ) {
154                 Py_DECREF( ( PyObject * ) text->compiled );
155                 text->compiled = NULL;
156         }
157 }
158
159 /*****************************************************************************
160 * Description: Creates the bpy module and adds it to sys.modules for importing
161 *****************************************************************************/
162 static void bpy_init_modules( void )
163 {
164         PyObject *mod;
165         
166         mod = PyModule_New("bpy");
167         
168         PyModule_AddObject( mod, "data", BPY_rna_module() );
169         /* PyModule_AddObject( mod, "doc", BPY_rna_doc() ); */
170         PyModule_AddObject( mod, "types", BPY_rna_types() );
171         PyModule_AddObject( mod, "props", BPY_rna_props() );
172         PyModule_AddObject( mod, "__ops__", BPY_operator_module() ); /* ops is now a python module that does the conversion from SOME_OT_foo -> some.foo */
173         PyModule_AddObject( mod, "ui", BPY_ui_module() ); // XXX very experimental, consider this a test, especially PyCObject is not meant to be permanent
174         
175         /* add the module so we can import it */
176         PyDict_SetItemString(PySys_GetObject("modules"), "bpy", mod);
177         Py_DECREF(mod);
178
179
180         /* stand alone utility modules not related to blender directly */
181         Geometry_Init();
182         Mathutils_Init();
183         BGL_Init();
184 }
185
186 void BPY_update_modules( void )
187 {
188 #if 0 // slow, this runs all the time poll, draw etc 100's of time a sec.
189         PyObject *mod= PyImport_ImportModuleLevel("bpy", NULL, NULL, NULL, 0);
190         PyModule_AddObject( mod, "data", BPY_rna_module() );
191         PyModule_AddObject( mod, "types", BPY_rna_types() ); // atm this does not need updating
192 #endif
193
194         /* refreshes the main struct */
195         BPY_update_rna_module();
196
197 }
198
199 /*****************************************************************************
200 * Description: This function creates a new Python dictionary object.
201 *****************************************************************************/
202 static PyObject *CreateGlobalDictionary( bContext *C )
203 {
204         PyObject *mod;
205         PyObject *dict = PyDict_New(  );
206         PyObject *item = PyUnicode_FromString( "__main__" );
207         PyDict_SetItemString( dict, "__builtins__", PyEval_GetBuiltins(  ) );
208         PyDict_SetItemString( dict, "__name__", item );
209         Py_DECREF(item);
210         
211         // XXX - put somewhere more logical
212         {
213                 PyMethodDef *ml;
214                 static PyMethodDef bpy_prop_meths[] = {
215                         {"FloatProperty", (PyCFunction)BPy_FloatProperty, METH_VARARGS|METH_KEYWORDS, ""},
216                         {"IntProperty", (PyCFunction)BPy_IntProperty, METH_VARARGS|METH_KEYWORDS, ""},
217                         {"BoolProperty", (PyCFunction)BPy_BoolProperty, METH_VARARGS|METH_KEYWORDS, ""},
218                         {"StringProperty", (PyCFunction)BPy_StringProperty, METH_VARARGS|METH_KEYWORDS, ""},
219                         {NULL, NULL, 0, NULL}
220                 };
221                 
222                 for(ml = bpy_prop_meths; ml->ml_name; ml++) {
223                         PyDict_SetItemString( dict, ml->ml_name, PyCFunction_New(ml, NULL));
224                 }
225         }
226         
227         /* add bpy to global namespace */
228         mod= PyImport_ImportModuleLevel("bpy", NULL, NULL, NULL, 0);
229         PyDict_SetItemString( dict, "bpy", mod );
230         Py_DECREF(mod);
231         
232         return dict;
233 }
234
235 /* must be called before Py_Initialize */
236 void BPY_start_python_path(void)
237 {
238         char *py_path_bundle= BLI_gethome_folder("python", BLI_GETHOME_ALL);
239
240         if(py_path_bundle==NULL)
241                 return;
242
243         /* set the environment path */
244         printf("found bundled python: %s\n", py_path_bundle);
245
246 #if 0
247         BLI_setenv("PYTHONHOME", py_path_bundle);
248         BLI_setenv("PYTHONPATH", py_path_bundle);
249 #endif
250
251         {
252                 static wchar_t py_path_bundle_wchar[FILE_MAXDIR];
253
254                 mbstowcs(py_path_bundle_wchar, py_path_bundle, FILE_MAXDIR);
255                 Py_SetPythonHome(py_path_bundle_wchar);
256         }
257 }
258
259
260 void BPY_start_python( int argc, char **argv )
261 {
262         PyThreadState *py_tstate = NULL;
263         
264         BPY_start_python_path(); /* allow to use our own included python */
265
266         Py_Initialize(  );
267         
268         // PySys_SetArgv( argc, argv); // broken in py3, not a huge deal
269         /* sigh, why do python guys not have a char** version anymore? :( */
270         {
271                 int i;
272                 PyObject *py_argv= PyList_New(argc);
273
274                 for (i=0; i<argc; i++)
275                         PyList_SET_ITEM(py_argv, i, PyUnicode_FromString(argv[i]));
276
277                 PySys_SetObject("argv", py_argv);
278                 Py_DECREF(py_argv);
279         }
280         
281         /* Initialize thread support (also acquires lock) */
282         PyEval_InitThreads();
283         
284         
285         /* bpy.* and lets us import it */
286         bpy_init_modules(); 
287
288         { /* our own import and reload functions */
289                 PyObject *item;
290                 //PyObject *m = PyImport_AddModule("__builtin__");
291                 //PyObject *d = PyModule_GetDict(m);
292                 PyObject *d = PyEval_GetBuiltins(  );
293                 PyDict_SetItemString(d, "reload",               item=PyCFunction_New(bpy_reload_meth, NULL));   Py_DECREF(item);
294                 PyDict_SetItemString(d, "__import__",   item=PyCFunction_New(bpy_import_meth, NULL));   Py_DECREF(item);
295         }
296         
297         pyrna_alloc_types();
298
299         py_tstate = PyGILState_GetThisThreadState();
300         PyEval_ReleaseThread(py_tstate);
301 }
302
303 void BPY_end_python( void )
304 {
305         // fprintf(stderr, "Ending Python!\n");
306
307         PyGILState_Ensure(); /* finalizing, no need to grab the state */
308         
309         // free other python data.
310         pyrna_free_types();
311
312         /* clear all python data from structs */
313         
314         Py_Finalize(  );
315         
316 #ifdef TIME_PY_RUN
317         // measure time since py started
318         bpy_timer = PIL_check_seconds_timer() - bpy_timer;
319
320         printf("*bpy stats* - ");
321         printf("tot exec: %d,  ", bpy_timer_count);
322         printf("tot run: %.4fsec,  ", bpy_timer_run_tot);
323         if(bpy_timer_count>0)
324                 printf("average run: %.6fsec,  ", (bpy_timer_run_tot/bpy_timer_count));
325
326         if(bpy_timer>0.0)
327                 printf("tot usage %.4f%%", (bpy_timer_run_tot/bpy_timer)*100.0);
328
329         printf("\n");
330
331         // fprintf(stderr, "Ending Python Done!\n");
332
333 #endif
334
335 }
336
337 /* Can run a file or text block */
338 int BPY_run_python_script( bContext *C, const char *fn, struct Text *text, struct ReportList *reports)
339 {
340         PyObject *py_dict, *py_result= NULL;
341         PyGILState_STATE gilstate;
342         
343         if (fn==NULL && text==NULL) {
344                 return 0;
345         }
346         
347         bpy_context_set(C, &gilstate);
348         
349         py_dict = CreateGlobalDictionary(C);
350
351         if (text) {
352                 
353                 if( !text->compiled ) { /* if it wasn't already compiled, do it now */
354                         char *buf = txt_to_buf( text );
355
356                         text->compiled =
357                                 Py_CompileString( buf, text->id.name+2, Py_file_input );
358
359                         MEM_freeN( buf );
360
361                         if( PyErr_Occurred(  ) ) {
362                                 BPY_free_compiled_text( text );
363                         }
364                 }
365                 if(text->compiled)
366                         py_result =  PyEval_EvalCode( text->compiled, py_dict, py_dict );
367                 
368         } else {
369 #if 0
370                 char *pystring;
371                 pystring= malloc(strlen(fn) + 32);
372                 pystring[0]= '\0';
373                 sprintf(pystring, "exec(open(r'%s').read())", fn);
374                 py_result = PyRun_String( pystring, Py_file_input, py_dict, py_dict );
375                 free(pystring);
376 #else
377                 FILE *fp= fopen(fn, "r");               
378                 if(fp) {
379                         py_result = PyRun_File(fp, fn, Py_file_input, py_dict, py_dict);
380                         fclose(fp);
381                 }
382                 else {
383                         PyErr_Format(PyExc_SystemError, "Python file \"%s\" could not be opened: %s", fn, strerror(errno));
384                         py_result= NULL;
385                 }
386 #endif
387         }
388         
389         if (!py_result) {
390                 BPy_errors_to_report(reports);
391         } else {
392                 Py_DECREF( py_result );
393         }
394         
395         Py_DECREF(py_dict);
396         
397         bpy_context_clear(C, &gilstate);
398
399         return py_result ? 1:0;
400 }
401
402
403 /* TODO - move into bpy_space.c ? */
404 /* GUI interface routines */
405
406 /* Copied from Draw.c */
407 static void exit_pydraw( SpaceScript * sc, short err )
408 {
409         Script *script = NULL;
410
411         if( !sc || !sc->script )
412                 return;
413
414         script = sc->script;
415
416         if( err ) {
417                 BPy_errors_to_report(NULL); // TODO, reports
418                 script->flags = 0;      /* mark script struct for deletion */
419                 SCRIPT_SET_NULL(script);
420                 script->scriptname[0] = '\0';
421                 script->scriptarg[0] = '\0';
422 // XXX 2.5              error_pyscript();
423 // XXX 2.5              scrarea_queue_redraw( sc->area );
424         }
425
426 #if 0 // XXX 2.5
427         BPy_Set_DrawButtonsList(sc->but_refs);
428         BPy_Free_DrawButtonsList(); /*clear all temp button references*/
429 #endif
430
431         sc->but_refs = NULL;
432         
433         Py_XDECREF( ( PyObject * ) script->py_draw );
434         Py_XDECREF( ( PyObject * ) script->py_event );
435         Py_XDECREF( ( PyObject * ) script->py_button );
436
437         script->py_draw = script->py_event = script->py_button = NULL;
438 }
439
440 static int bpy_run_script_init(bContext *C, SpaceScript * sc)
441 {
442         if (sc->script==NULL) 
443                 return 0;
444         
445         if (sc->script->py_draw==NULL && sc->script->scriptname[0] != '\0')
446                 BPY_run_python_script(C, sc->script->scriptname, NULL, NULL);
447                 
448         if (sc->script->py_draw==NULL)
449                 return 0;
450         
451         return 1;
452 }
453
454 int BPY_run_script_space_draw(const struct bContext *C, SpaceScript * sc)
455 {
456         if (bpy_run_script_init( (bContext *)C, sc)) {
457                 PyGILState_STATE gilstate = PyGILState_Ensure();
458                 PyObject *result = PyObject_CallObject( sc->script->py_draw, NULL );
459                 
460                 if (result==NULL)
461                         exit_pydraw(sc, 1);
462                         
463                 PyGILState_Release(gilstate);
464         }
465         return 1;
466 }
467
468 // XXX - not used yet, listeners dont get a context
469 int BPY_run_script_space_listener(bContext *C, SpaceScript * sc)
470 {
471         if (bpy_run_script_init(C, sc)) {
472                 PyGILState_STATE gilstate = PyGILState_Ensure();
473                 
474                 PyObject *result = PyObject_CallObject( sc->script->py_draw, NULL );
475                 
476                 if (result==NULL)
477                         exit_pydraw(sc, 1);
478                         
479                 PyGILState_Release(gilstate);
480         }
481         return 1;
482 }
483
484 void BPY_DECREF(void *pyob_ptr)
485 {
486         Py_DECREF((PyObject *)pyob_ptr);
487 }
488
489 #if 0
490 /* called from the the scripts window, assume context is ok */
491 int BPY_run_python_script_space(const char *modulename, const char *func)
492 {
493         PyObject *py_dict, *py_result= NULL;
494         char pystring[512];
495         PyGILState_STATE gilstate;
496         
497         /* for calling the module function */
498         PyObject *py_func, 
499         
500         gilstate = PyGILState_Ensure();
501         
502         py_dict = CreateGlobalDictionary(C);
503         
504         PyObject *module = PyImport_ImportModule(scpt->script.filename);
505         if (module==NULL) {
506                 PyErr_SetFormat(PyExc_SystemError, "could not import '%s'", scpt->script.filename);
507         }
508         else {
509                 py_func = PyObject_GetAttrString(modulename, func);
510                 if (py_func==NULL) {
511                         PyErr_SetFormat(PyExc_SystemError, "module has no function '%s.%s'\n", scpt->script.filename, func);
512                 }
513                 else {
514                         Py_DECREF(py_func);
515                         if (!PyCallable_Check(py_func)) {
516                                 PyErr_SetFormat(PyExc_SystemError, "module item is not callable '%s.%s'\n", scpt->script.filename, func);
517                         }
518                         else {
519                                 py_result= PyObject_CallObject(py_func, NULL); // XXX will need args eventually
520                         }
521                 }
522         }
523         
524         if (!py_result) {
525                 BPy_errors_to_report(NULL); // TODO - reports
526         } else
527                 Py_DECREF( py_result );
528         
529         Py_XDECREF(module);
530         
531         Py_DECREF(py_dict);
532         
533         PyGILState_Release(gilstate);
534         return 1;
535 }
536 #endif
537
538 // #define TIME_REGISTRATION
539
540 #ifdef TIME_REGISTRATION
541 #include "PIL_time.h"
542 #endif
543
544 /* for use by BPY_run_ui_scripts only */
545 static int bpy_import_module(char *modname, int reload)
546 {
547         PyObject *mod= PyImport_ImportModuleLevel(modname, NULL, NULL, NULL, 0);
548         if (mod) {
549                 if (reload) {
550                         PyObject *mod_orig= mod;
551                         mod= PyImport_ReloadModule(mod);
552                         Py_DECREF(mod_orig);
553                 }
554         }
555
556         if(mod) {
557                 Py_DECREF(mod); /* could be NULL from reloading */
558                 return 0;
559         } else {
560                 return -1;
561         }
562 }
563
564 /* XXX this is temporary, need a proper script registration system for 2.5 */
565 void BPY_run_ui_scripts(bContext *C, int reload)
566 {
567 #ifdef TIME_REGISTRATION
568         double time = PIL_check_seconds_timer();
569 #endif
570         DIR *dir; 
571         struct dirent *de;
572         char *file_extension;
573         char *dirname;
574         char path[FILE_MAX];
575         char *dirs[] = {"ui", "io", NULL};
576         int path_flags[] = {BLI_GETHOME_LOCAL|BLI_GETHOME_SYSTEM, BLI_GETHOME_USER}; /* SYSTEM / NON-SYSTEM */
577         int a, err, flag_iter;
578         
579         PyGILState_STATE gilstate;
580         PyObject *sys_path;
581
582         bpy_context_set(C, &gilstate);
583
584         sys_path= PySys_GetObject("path"); /* borrow */
585         PyList_Insert(sys_path, 0, Py_None); /* place holder, resizes the list */
586
587         /* Scan system scripts first, then local/user */
588         for(flag_iter=0; flag_iter < sizeof(path_flags)/sizeof(int); flag_iter++) {
589                 
590                 for(a=0; dirs[a]; a++) {
591                         dirname= BLI_gethome_folder(dirs[a], path_flags[flag_iter]);
592
593                         if(!dirname)
594                                 continue;
595
596                         dir = opendir(dirname);
597
598                         if(!dir)
599                                 continue;
600                         
601                         /* set the first dir in the sys.path for fast importing of modules */
602                         PyList_SetItem(sys_path, 0, PyUnicode_FromString(dirname)); /* steals the ref */
603                                 
604                         while((de = readdir(dir)) != NULL) {
605                                 /* We could stat the file but easier just to let python
606                                  * import it and complain if theres a problem */
607                                 err = 0;
608
609                                 if (de->d_name[0] == '.') {
610                                         /* do nothing, probably .svn */
611                                 }
612                                 else if ((file_extension = strstr(de->d_name, ".py"))) {
613                                         /* normal py files? */
614                                         if(file_extension && file_extension[3] == '\0') {
615                                                 de->d_name[(file_extension - de->d_name)] = '\0';
616                                                 err= bpy_import_module(de->d_name, reload);
617                                         }
618                                 }
619 #ifndef __linux__
620                                 else if( BLI_join_dirfile(path, dirname, de->d_name), S_ISDIR(BLI_exist(path))) {
621 #else
622                                 else if(de->d_type==DT_DIR) {
623                                         BLI_join_dirfile(path, dirname, de->d_name);
624 #endif
625                                         /* support packages */
626                                         BLI_join_dirfile(path, path, "__init__.py");
627
628                                         if(BLI_exists(path)) {
629                                                 err= bpy_import_module(de->d_name, reload);
630                                         }
631                                 }
632
633                                 if(err==-1) {
634                                         BPy_errors_to_report(NULL);
635                                         fprintf(stderr, "unable to import %s/%s\n", dirname, de->d_name);
636                                 }
637                         }
638
639                         closedir(dir);
640                 }
641         }
642         
643         PyList_SetSlice(sys_path, 0, 1, NULL); /* remove the first item */
644
645         bpy_context_clear(C, &gilstate);
646         
647 #ifdef TIME_REGISTRATION
648         printf("script time %f\n", (PIL_check_seconds_timer()-time));
649 #endif
650
651         /* reset the timer so as not to take loading into the stats */
652         bpy_timer_count = 0;
653 }
654
655 /* ****************************************** */
656 /* Drivers - PyExpression Evaluation */
657
658 /* for pydrivers (drivers using one-line Python expressions to express relationships between targets) */
659 PyObject *bpy_pydriver_Dict = NULL;
660
661 /* For faster execution we keep a special dictionary for pydrivers, with
662  * the needed modules and aliases. 
663  */
664 static int bpy_pydriver_create_dict(void)
665 {
666         PyObject *d, *mod;
667         
668         /* validate namespace for driver evaluation */
669         if (bpy_pydriver_Dict) return -1;
670
671         d = PyDict_New();
672         if (d == NULL) 
673                 return -1;
674         else
675                 bpy_pydriver_Dict = d;
676
677         /* import some modules: builtins, bpy, math, (Blender.noise )*/
678         PyDict_SetItemString(d, "__builtins__", PyEval_GetBuiltins());
679
680         mod = PyImport_ImportModule("math");
681         if (mod) {
682                 PyDict_Merge(d, PyModule_GetDict(mod), 0); /* 0 - dont overwrite existing values */
683                 
684                 /* Only keep for backwards compat! - just import all math into root, they are standard */
685                 PyDict_SetItemString(d, "math", mod);
686                 PyDict_SetItemString(d, "m", mod);
687                 Py_DECREF(mod);
688         } 
689         
690         /* add bpy to global namespace */
691         mod= PyImport_ImportModuleLevel("bpy", NULL, NULL, NULL, 0);
692         if (mod) {
693                 PyDict_SetItemString(bpy_pydriver_Dict, "bpy", mod);
694                 Py_DECREF(mod);
695         }
696         
697         
698 #if 0 // non existant yet
699         mod = PyImport_ImportModule("Blender.Noise");
700         if (mod) {
701                 PyDict_SetItemString(d, "noise", mod);
702                 PyDict_SetItemString(d, "n", mod);
703                 Py_DECREF(mod);
704         } else {
705                 PyErr_Clear();
706         }
707         
708         /* If there's a Blender text called pydrivers.py, import it.
709          * Users can add their own functions to this module. 
710          */
711         if (G.f & G_DOSCRIPTLINKS) {
712                 mod = importText("pydrivers"); /* can also use PyImport_Import() */
713                 if (mod) {
714                         PyDict_SetItemString(d, "pydrivers", mod);
715                         PyDict_SetItemString(d, "p", mod);
716                         Py_DECREF(mod);
717                 } else {
718                         PyErr_Clear();
719                 }
720         }
721 #endif // non existant yet
722         
723         return 0;
724 }
725
726 /* Update function, it gets rid of pydrivers global dictionary, forcing
727  * BPY_pydriver_eval to recreate it. This function is used to force
728  * reloading the Blender text module "pydrivers.py", if available, so
729  * updates in it reach pydriver evaluation. 
730  */
731 void BPY_pydriver_update(void)
732 {
733         PyGILState_STATE gilstate = PyGILState_Ensure();
734
735         if (bpy_pydriver_Dict) { /* free the global dict used by pydrivers */
736                 PyDict_Clear(bpy_pydriver_Dict);
737                 Py_DECREF(bpy_pydriver_Dict);
738                 bpy_pydriver_Dict = NULL;
739         }
740
741         PyGILState_Release(gilstate);
742
743         return;
744 }
745
746 /* error return function for BPY_eval_pydriver */
747 static float pydriver_error(ChannelDriver *driver) 
748 {
749         if (bpy_pydriver_Dict) { /* free the global dict used by pydrivers */
750                 PyDict_Clear(bpy_pydriver_Dict);
751                 Py_DECREF(bpy_pydriver_Dict);
752                 bpy_pydriver_Dict = NULL;
753         }
754
755         driver->flag |= DRIVER_FLAG_INVALID; /* py expression failed */
756         fprintf(stderr, "\nError in Driver: The following Python expression failed:\n\t'%s'\n\n", driver->expression);
757         
758         BPy_errors_to_report(NULL); // TODO - reports
759
760         return 0.0f;
761 }
762
763 /* This evals py driver expressions, 'expr' is a Python expression that
764  * should evaluate to a float number, which is returned. 
765  */
766 float BPY_pydriver_eval (ChannelDriver *driver)
767 {
768         PyObject *driver_vars=NULL;
769         PyObject *retval;
770         PyGILState_STATE gilstate;
771         
772         DriverTarget *dtar;
773         float result = 0.0f; /* default return */
774         char *expr = NULL;
775         short targets_ok= 1;
776         
777         /* sanity checks - should driver be executed? */
778         if ((driver == NULL) /*|| (G.f & G_DOSCRIPTLINKS)==0*/) 
779                 return result;
780         
781         /* get the py expression to be evaluated */
782         expr = driver->expression; 
783         if ((expr == NULL) || (expr[0]=='\0')) 
784                 return result;
785
786         gilstate = PyGILState_Ensure();
787         
788         /* init global dictionary for py-driver evaluation settings */
789         if (!bpy_pydriver_Dict) {
790                 if (bpy_pydriver_create_dict() != 0) {
791                         fprintf(stderr, "Pydriver error: couldn't create Python dictionary");
792                         PyGILState_Release(gilstate);
793                         return result;
794                 }
795         }
796         
797         /* add target values to a dict that will be used as '__locals__' dict */
798         driver_vars = PyDict_New(); // XXX do we need to decref this?
799         for (dtar= driver->targets.first; dtar; dtar= dtar->next) {
800                 PyObject *driver_arg = NULL;
801                 float tval = 0.0f;
802                 
803                 /* try to get variable value */
804                 tval= driver_get_target_value(driver, dtar);
805                 driver_arg= PyFloat_FromDouble((double)tval);
806                 
807                 /* try to add to dictionary */
808                 if (PyDict_SetItemString(driver_vars, dtar->name, driver_arg)) {
809                         /* this target failed - bad name */
810                         if (targets_ok) {
811                                 /* first one - print some extra info for easier identification */
812                                 fprintf(stderr, "\nBPY_pydriver_eval() - Error while evaluating PyDriver:\n");
813                                 targets_ok= 0;
814                         }
815                         
816                         fprintf(stderr, "\tBPY_pydriver_eval() - couldn't add variable '%s' to namespace \n", dtar->name);
817                         BPy_errors_to_report(NULL); // TODO - reports
818                 }
819         }
820         
821         /* execute expression to get a value */
822         retval = PyRun_String(expr, Py_eval_input, bpy_pydriver_Dict, driver_vars);
823         
824         /* decref the driver vars first...  */
825         Py_DECREF(driver_vars);
826         
827         /* process the result */
828         if (retval == NULL) {
829                 result = pydriver_error(driver);
830                 PyGILState_Release(gilstate);
831                 return result;
832         }
833
834         result = (float)PyFloat_AsDouble(retval);
835         Py_DECREF(retval);
836         
837         if ((result == -1) && PyErr_Occurred()) {
838                 result = pydriver_error(driver);
839                 PyGILState_Release(gilstate);
840                 return result;
841         }
842         
843         /* all fine, make sure the "invalid expression" flag is cleared */
844         driver->flag &= ~DRIVER_FLAG_INVALID;
845
846         PyGILState_Release(gilstate);
847
848         return result;
849 }
850
851 int BPY_button_eval(bContext *C, char *expr, double *value)
852 {
853         PyGILState_STATE gilstate;
854         PyObject *dict, *retval;
855         int error_ret = 0;
856         
857         if (!value || !expr || expr[0]=='\0') return -1;
858         
859         bpy_context_set(C, &gilstate);
860         
861         dict= CreateGlobalDictionary(C);
862         retval = PyRun_String(expr, Py_eval_input, dict, dict);
863         
864         if (retval == NULL) {
865                 error_ret= -1;
866         }
867         else {
868                 double val;
869
870                 if(PyTuple_Check(retval)) {
871                         /* Users my have typed in 10km, 2m
872                          * add up all values */
873                         int i;
874                         val= 0.0;
875
876                         for(i=0; i<PyTuple_GET_SIZE(retval); i++) {
877                                 val+= PyFloat_AsDouble(PyTuple_GET_ITEM(retval, i));
878                         }
879                 }
880                 else {
881                         val = PyFloat_AsDouble(retval);
882                 }
883                 Py_DECREF(retval);
884                 
885                 if(val==-1 && PyErr_Occurred()) {
886                         error_ret= -1;
887                 }
888                 else {
889                         *value= val;
890                 }
891         }
892         
893         if(error_ret) {
894                 BPy_errors_to_report(CTX_wm_reports(C));
895         }
896         
897         Py_DECREF(dict);
898         bpy_context_clear(C, &gilstate);
899         
900         return error_ret;
901 }
902