Get rid of the file touch hack.

If user cancels, there's an issue with leftover files.
Instead use a hash to record files that have akready been registered for
generation and skip them if so.

That should guarantee things will go smoothly and when a file exists it
is assumed to be valid.

source/blender/blenkernel/BKE_sequencer.h

@@ -34,6 +34,7 @@ struct bContext;
 struct EvaluationContext;
 struct StripColorBalance;
 struct Editing;
+struct GSet;
 struct ImBuf;
 struct Main;
 struct Mask;
@@ -236,7 +237,7 @@ struct StripElem *BKE_sequencer_give_stripelem(struct Sequence *seq, int cfra);
 void BKE_sequencer_update_changed_seq_and_deps(struct Scene *scene, struct Sequence *changed_seq, int len_change, int ibuf_change);
 bool BKE_sequencer_input_have_to_preprocess(const SeqRenderData *context, struct Sequence *seq, float cfra);
 
-struct SeqIndexBuildContext *BKE_sequencer_proxy_rebuild_context(struct Main *bmain, struct Scene *scene, struct Sequence *seq);
+struct SeqIndexBuildContext *BKE_sequencer_proxy_rebuild_context(struct Main *bmain, struct Scene *scene, struct Sequence *seq, struct GSet *file_list);
 void BKE_sequencer_proxy_rebuild(struct SeqIndexBuildContext *context, short *stop, short *do_update, float *progress);
 void BKE_sequencer_proxy_rebuild_finish(struct SeqIndexBuildContext *context, bool stop);
 

source/blender/blenkernel/intern/sequencer.c

@@ -1532,7 +1532,7 @@ static void seq_proxy_build_frame(const SeqRenderData *context, Sequence *seq, i
 	IMB_freeImBuf(ibuf);
 }
 
-SeqIndexBuildContext *BKE_sequencer_proxy_rebuild_context(Main *bmain, Scene *scene, Sequence *seq)
+SeqIndexBuildContext *BKE_sequencer_proxy_rebuild_context(Main *bmain, Scene *scene, Sequence *seq, struct GSet *file_list)
 {
 	SeqIndexBuildContext *context;
 	Sequence *nseq;
@@ -1565,7 +1565,7 @@ SeqIndexBuildContext *BKE_sequencer_proxy_rebuild_context(Main *bmain, Scene *sc
 		if (nseq->anim) {
 			context->index_context = IMB_anim_index_rebuild_context(nseq->anim,
 			        context->tc_flags, context->size_flags, context->quality,
-			        context->overwrite);
+			        context->overwrite, file_list);
 		}
 	}
 

source/blender/editors/space_clip/clip_ops.c

@@ -1343,7 +1343,7 @@ static int clip_rebuild_proxy_exec(bContext *C, wmOperator *UNUSED(op))
 	if (clip->anim) {
 		pj->index_context = IMB_anim_index_rebuild_context(clip->anim, clip->proxy.build_tc_flag,
 		                                                   clip->proxy.build_size_flag, clip->proxy.quality,
-		                                                   true);
+		                                                   true, NULL);
 	}
 
 	WM_jobs_customdata_set(wm_job, pj, proxy_freejob);

source/blender/editors/space_sequencer/sequencer_edit.c

@@ -37,6 +37,7 @@
 #include "BLI_blenlib.h"
 #include "BLI_math.h"
 #include "BLI_utildefines.h"
+#include "BLI_ghash.h"
 
 #include "BLF_translation.h"
 
@@ -181,6 +182,7 @@ static void seq_proxy_build_job(const bContext *C)
 	struct SeqIndexBuildContext *context;
 	LinkData *link;
 	Sequence *seq;
+	GSet *file_list;
 	
 	if (ed == NULL) {
 		return;
@@ -202,16 +204,19 @@ static void seq_proxy_build_job(const bContext *C)
 		WM_jobs_callbacks(wm_job, proxy_startjob, NULL, NULL, proxy_endjob);
 	}
 
+	file_list = BLI_gset_new(BLI_ghashutil_strhash_p, BLI_ghashutil_strcmp, "file list");
 	SEQP_BEGIN (ed, seq)
 	{
 		if ((seq->flag & SELECT)) {
-			context = BKE_sequencer_proxy_rebuild_context(pj->main, pj->scene, seq);
+			context = BKE_sequencer_proxy_rebuild_context(pj->main, pj->scene, seq, file_list);
 			link = BLI_genericNodeN(context);
 			BLI_addtail(&pj->queue, link);
 		}
 	}
 	SEQ_END
 
+	BLI_gset_free(file_list, MEM_freeN);
+	
 	if (!WM_jobs_is_running(wm_job)) {
 		G.is_break = false;
 		WM_jobs_start(CTX_wm_manager(C), wm_job);
@@ -3362,18 +3367,21 @@ static int sequencer_rebuild_proxy_exec(bContext *C, wmOperator *UNUSED(op))
 	Scene *scene = CTX_data_scene(C);
 	Editing *ed = BKE_sequencer_editing_get(scene, false);
 	Sequence *seq;
+	GSet *file_list;
 	
 	if (ed == NULL) {
 		return OPERATOR_CANCELLED;
 	}
 
+	file_list = BLI_gset_new(BLI_ghashutil_strhash_p, BLI_ghashutil_strcmp, "file list");
+	
 	SEQP_BEGIN(ed, seq)
 	{
 		if ((seq->flag & SELECT)) {
 			struct SeqIndexBuildContext *context;
 			short stop = 0, do_update;
 			float progress;
-			context = BKE_sequencer_proxy_rebuild_context(bmain, scene, seq);
+			context = BKE_sequencer_proxy_rebuild_context(bmain, scene, seq, file_list);
 			BKE_sequencer_proxy_rebuild(context, &stop, &do_update, &progress);
 			BKE_sequencer_proxy_rebuild_finish(context, 0);
 			BKE_sequencer_free_imbuf(scene, &ed->seqbase, false);
@@ -3381,6 +3389,8 @@ static int sequencer_rebuild_proxy_exec(bContext *C, wmOperator *UNUSED(op))
 	}
 	SEQ_END
 
+	BLI_gset_free(file_list, MEM_freeN);
+	
 	return OPERATOR_FINISHED;
 }
 

source/blender/imbuf/IMB_imbuf.h

@@ -86,6 +86,7 @@ struct anim;
 
 struct ColorManagedDisplay;
 
+struct GSet;
 /**
  *
  * \attention Defined in allocimbuf.c
@@ -243,7 +244,7 @@ struct IndexBuildContext;
 /* prepare context for proxies/imecodes builder */
 struct IndexBuildContext *IMB_anim_index_rebuild_context(struct anim *anim, IMB_Timecode_Type tcs_in_use,
                                                          IMB_Proxy_Size proxy_sizes_in_use, int quality,
-                                                         const bool overwite);
+                                                         const bool overwite, struct GSet *file_list);
 
 /* will rebuild all used indices and proxies at once */
 void IMB_anim_index_rebuild(struct IndexBuildContext *context,

source/blender/imbuf/intern/indexer.c

@@ -35,6 +35,7 @@
 #include "BLI_path_util.h"
 #include "BLI_string.h"
 #include "BLI_fileops.h"
+#include "BLI_ghash.h"
 
 #include "IMB_indexer.h"
 #include "IMB_anim.h"
@@ -1149,12 +1150,31 @@ static void index_rebuild_fallback(FallbackIndexBuilderContext *context,
 
 IndexBuildContext *IMB_anim_index_rebuild_context(struct anim *anim, IMB_Timecode_Type tcs_in_use,
                                                   IMB_Proxy_Size proxy_sizes_in_use, int quality,
-                                                  const bool overwrite)
+                                                  const bool overwrite, GSet *file_list)
 {
 	IndexBuildContext *context = NULL;
 	IMB_Proxy_Size proxy_sizes_to_build = proxy_sizes_in_use;
 	int i;
 
+	/* Don't generate the same file twice! */
+	if (file_list) {
+		for (i = 0; i < IMB_PROXY_MAX_SLOT; ++i) {
+			IMB_Proxy_Size proxy_size = proxy_sizes[i];
+			if (proxy_size & proxy_sizes_to_build) {
+				char filename[FILE_MAX];
+				get_proxy_filename(anim, proxy_size, filename, false);
+
+				if (BLI_gset_haskey(file_list, filename)) {
+					proxy_sizes_to_build &= ~proxy_size;
+					printf("Proxy: %s already registered for generation, skipping\n", filename);
+				}
+				else {
+					BLI_gset_insert(file_list, BLI_strdup(filename));
+				}
+			}
+		}
+	}
+	
 	if (!overwrite) {
 		IMB_Proxy_Size built_proxies = IMB_anim_proxy_get_existing(anim);
 		if (built_proxies != 0) {
@@ -1166,27 +1186,13 @@ IndexBuildContext *IMB_anim_index_rebuild_context(struct anim *anim, IMB_Timecod
 					get_proxy_filename(anim, proxy_size, filename, false);
 					printf("Skipping proxy: %s\n", filename);
 				}
-				/* if file doesn't exist, create it here so subsequent runs won't re-add it for generation */
-				else if (proxy_size & proxy_sizes_to_build) {
-					char filename[FILE_MAX];
-					get_proxy_filename(anim, proxy_size, filename, false);
-					BLI_file_touch(filename);
-				}
-			}
-		}
-		else {
-			for (i = 0; i < IMB_PROXY_MAX_SLOT; ++i) {
-				IMB_Proxy_Size proxy_size = proxy_sizes[i];
-				if (proxy_size & proxy_sizes_to_build) {
-					char filename[FILE_MAX];
-					get_proxy_filename(anim, proxy_size, filename, false);
-					BLI_file_touch(filename);
-				}
 			}
 		}
 		proxy_sizes_to_build &= ~built_proxies;
 	}
 	
+	fflush(stdout);
+
 	if (proxy_sizes_to_build == 0) {
 		return NULL;
 	}