T39690: Modifications to Blender's 'temp dir' system.

Current temporary data of Blender suffers one major issue - default 'temp' dir on Windows is never
automatically cleaned up, and can end being quite big when used by Blender, especially when we have
to store per-process data (using getpid() in file names).

To address this, this patch:
* Divides tempdir paths in two, one for 'base' temp dir (the same as previous unique tempdir path),
  the other is a mkdtemp-generated sub-dir, specific to each Blender instance.
* Only uses base tempdir when we need some shallow persistance accross Blender sessions - and we always
  reuse the same filename (quit.blend...) or generate small file (crash reports...).
* Uses temp sub-dir for heavy files like pointcache or renderEXRs (Save Buffer option).
* Erases temp sub-dir on quit or crash.

To get this working it also adds a working 'recursive delete' to BLI_delete() under Windows.

Note that, as in current code, the 'recover render result' hack-feature that was possible
with SaveBuffer option is still removed. A real renderresult cache feature will be added
soon, though.

Reviewers: campbellbarton, brecht, sergey

Reviewed By: campbellbarton, sergey

CC: sergey

Differential Revision: https://developer.blender.org/D531

3 files changed, 9 insertions, 7 deletions

diff --git a/source/blender/windowmanager/intern/wm_files.c b/source/blender/windowmanager/intern/wm_files.c
index 1ec2e6a3ee0..0bc6442348c 100644
--- a/source/blender/windowmanager/intern/wm_files.c
+++ b/source/blender/windowmanager/intern/wm_files.c
@@ -299,7 +299,7 @@ static void wm_init_userdef(bContext *C, const bool from_memory)
 	}
 
 	/* update tempdir from user preferences */
-	BLI_init_temporary_dir(U.tempdir);
+	BLI_temp_dir_init(U.tempdir);
 
 	BKE_userdef_state();
 }
@@ -591,7 +591,7 @@ int wm_homefile_read(bContext *C, ReportList *reports, bool from_memory, const c
 		if (BLI_listbase_is_empty(&wmbase)) {
 			wm_clear_default_size(C);
 		}
-		BLI_init_temporary_dir(U.tempdir);
+		BLI_temp_dir_init(U.tempdir);
 
 #ifdef WITH_PYTHON_SECURITY
 		/* use alternative setting for security nuts
@@ -1058,14 +1058,14 @@ void wm_autosave_location(char *filepath)
 	 * BLI_make_file_string will create string that has it most likely on C:\
 	 * through get_default_root().
 	 * If there is no C:\tmp autosave fails. */
-	if (!BLI_exists(BLI_temporary_dir())) {
+	if (!BLI_exists(BLI_temp_dir_base())) {
 		savedir = BLI_get_folder_create(BLENDER_USER_AUTOSAVE, NULL);
 		BLI_make_file_string("/", filepath, savedir, pidstr);
 		return;
 	}
 #endif
 
-	BLI_make_file_string("/", filepath, BLI_temporary_dir(), pidstr);
+	BLI_make_file_string("/", filepath, BLI_temp_dir_base(), pidstr);
 }
 
 void WM_autosave_init(wmWindowManager *wm)
@@ -1129,7 +1129,7 @@ void wm_autosave_delete(void)
 
 	if (BLI_exists(filename)) {
 		char str[FILE_MAX];
-		BLI_make_file_string("/", str, BLI_temporary_dir(), BLENDER_QUIT_FILE);
+		BLI_make_file_string("/", str, BLI_temp_dir_base(), BLENDER_QUIT_FILE);
 
 		/* if global undo; remove tempsave, otherwise rename */
 		if (U.uiflag & USER_GLOBALUNDO) BLI_delete(filename, false, false);
diff --git a/source/blender/windowmanager/intern/wm_init_exit.c b/source/blender/windowmanager/intern/wm_init_exit.c
index f1c0457fb38..693c48cf8b9 100644
--- a/source/blender/windowmanager/intern/wm_init_exit.c
+++ b/source/blender/windowmanager/intern/wm_init_exit.c
@@ -405,7 +405,7 @@ void WM_exit_ext(bContext *C, const bool do_python)
 				/* save the undo state as quit.blend */
 				char filename[FILE_MAX];
 				
-				BLI_make_file_string("/", filename, BLI_temporary_dir(), BLENDER_QUIT_FILE);
+				BLI_make_file_string("/", filename, BLI_temp_dir_base(), BLENDER_QUIT_FILE);
 
 				if (BKE_undo_save_file(filename))
 					printf("Saved session recovery to '%s'\n", filename);
@@ -527,6 +527,8 @@ void WM_exit_ext(bContext *C, const bool do_python)
 		MEM_printmemlist();
 	}
 	wm_autosave_delete();
+
+	BLI_temp_dir_session_purge();
 }
 
 void WM_exit(bContext *C)
diff --git a/source/blender/windowmanager/intern/wm_operators.c b/source/blender/windowmanager/intern/wm_operators.c
index dd8881ef70b..ba454bb1818 100644
--- a/source/blender/windowmanager/intern/wm_operators.c
+++ b/source/blender/windowmanager/intern/wm_operators.c
@@ -2587,7 +2587,7 @@ void WM_recover_last_session(bContext *C, ReportList *reports)
 {
 	char filepath[FILE_MAX];
 	
-	BLI_make_file_string("/", filepath, BLI_temporary_dir(), BLENDER_QUIT_FILE);
+	BLI_make_file_string("/", filepath, BLI_temp_dir_base(), BLENDER_QUIT_FILE);
 	/* if reports==NULL, it's called directly without operator, we add a quick check here */
 	if (reports || BLI_exists(filepath)) {
 		G.fileflags |= G_FILE_RECOVER;