Report errno string when writing files fails

Screenshot ignored errors, some render code printed 'Saved' without checking for failure.

note: errno is now cleared from IMB_saveiff so all callers don't need to.

2 files changed, 42 insertions, 40 deletions

diff --git a/source/blender/render/intern/source/pipeline.c b/source/blender/render/intern/source/pipeline.c
index 1ac9dd8e716..75ef2fbb048 100644
--- a/source/blender/render/intern/source/pipeline.c
+++ b/source/blender/render/intern/source/pipeline.c
@@ -34,6 +34,7 @@
 #include <string.h>
 #include <stdlib.h>
 #include <stddef.h>
+#include <errno.h>
 
 #include "DNA_anim_types.h"
 #include "DNA_image_types.h"
@@ -198,6 +199,35 @@ static void stats_background(void *UNUSED(arg), RenderStats *rs)
 	fflush(stdout);
 }
 
+static void render_print_save_message(const char *name, int ok, int err)
+{
+	if (ok) {
+		printf("Saved: '%s'\n", name);
+	}
+	else {
+		printf("Render error (%s) cannot save: '%s'\n", strerror(err), name);
+	}
+}
+
+static int render_imbuf_write_stamp_test(
+        Scene *scene, struct RenderResult *rr, ImBuf *ibuf, const char *name,
+        const ImageFormatData *imf, bool stamp)
+{
+	int ok;
+
+	if (stamp) {
+		/* writes the name of the individual cameras */
+		ok = BKE_imbuf_write_stamp(scene, rr, ibuf, name, imf);
+	}
+	else {
+		ok = BKE_imbuf_write(ibuf, name, imf);
+	}
+
+	render_print_save_message(name, ok, errno);
+
+	return ok;
+}
+
 void RE_FreeRenderResult(RenderResult *res)
 {
 	render_result_free(res);
@@ -3209,8 +3239,8 @@ bool RE_WriteRenderViewsImage(ReportList *reports, RenderResult *rr, Scene *scen
 	if (ELEM(rd->im_format.imtype, R_IMF_IMTYPE_OPENEXR, R_IMF_IMTYPE_MULTILAYER) &&
 	    rd->im_format.views_format == R_IMF_VIEWS_MULTIVIEW)
 	{
-		RE_WriteRenderResult(reports, rr, name, &rd->im_format, true, NULL);
-		printf("Saved: %s\n", name);
+		ok = RE_WriteRenderResult(reports, rr, name, &rd->im_format, true, NULL);
+		render_print_save_message(name, ok, errno);
 	}
 
 	/* mono, legacy code */
@@ -3228,8 +3258,8 @@ bool RE_WriteRenderViewsImage(ReportList *reports, RenderResult *rr, Scene *scen
 			}
 
 			if (rd->im_format.imtype == R_IMF_IMTYPE_MULTILAYER) {
-				RE_WriteRenderResult(reports, rr, name, &rd->im_format, false, rv->name);
-				printf("Saved: %s\n", name);
+				ok = RE_WriteRenderResult(reports, rr, name, &rd->im_format, false, rv->name);
+				render_print_save_message(name, ok, errno);
 			}
 			else {
 				ImBuf *ibuf = render_result_rect_to_ibuf(rr, rd, view_id);
@@ -3237,18 +3267,7 @@ bool RE_WriteRenderViewsImage(ReportList *reports, RenderResult *rr, Scene *scen
 				IMB_colormanagement_imbuf_for_write(ibuf, true, false, &scene->view_settings,
 				                                    &scene->display_settings, &rd->im_format);
 
-				if (stamp) {
-					/* writes the name of the individual cameras */
-					ok = BKE_imbuf_write_stamp(scene, rr, ibuf, name, &rd->im_format);
-				}
-				else {
-					ok = BKE_imbuf_write(ibuf, name, &rd->im_format);
-				}
-
-				if (ok == false) {
-					printf("Render error: cannot save %s\n", name);
-				}
-				else printf("Saved: %s\n", name);
+				ok = render_imbuf_write_stamp_test(scene, rr, ibuf, name, &rd->im_format, stamp);
 
 				/* optional preview images for exr */
 				if (ok && rd->im_format.imtype == R_IMF_IMTYPE_OPENEXR && (rd->im_format.flag & R_IMF_FLAG_PREVIEW_JPG)) {
@@ -3263,14 +3282,7 @@ bool RE_WriteRenderViewsImage(ReportList *reports, RenderResult *rr, Scene *scen
 					IMB_colormanagement_imbuf_for_write(ibuf, true, false, &scene->view_settings,
 					                                    &scene->display_settings, &imf);
 
-					if (stamp) {
-						/* writes the name of the individual cameras */
-						ok = BKE_imbuf_write_stamp(scene, rr, ibuf, name, &imf);
-					}
-					else {
-						ok = BKE_imbuf_write(ibuf, name, &imf);
-					}
-					printf("Saved: %s\n", name);
+					ok = render_imbuf_write_stamp_test(scene, rr, ibuf, name, &imf, stamp);
 				}
 
 				/* imbuf knows which rects are not part of ibuf */
@@ -3299,15 +3311,7 @@ bool RE_WriteRenderViewsImage(ReportList *reports, RenderResult *rr, Scene *scen
 
 			ibuf_arr[2] = IMB_stereo3d_ImBuf(&scene->r.im_format, ibuf_arr[0], ibuf_arr[1]);
 
-			if (stamp)
-				ok = BKE_imbuf_write_stamp(scene, rr, ibuf_arr[2], name, &rd->im_format);
-			else
-				ok = BKE_imbuf_write(ibuf_arr[2], name, &rd->im_format);
-
-			if (ok == false)
-				printf("Render error: cannot save %s\n", name);
-			else
-				printf("Saved: %s\n", name);
+			ok = render_imbuf_write_stamp_test(scene, rr, ibuf_arr[2], name, &rd->im_format, stamp);
 
 			/* optional preview images for exr */
 			if (ok && rd->im_format.imtype == R_IMF_IMTYPE_OPENEXR &&
@@ -3325,12 +3329,7 @@ bool RE_WriteRenderViewsImage(ReportList *reports, RenderResult *rr, Scene *scen
 				IMB_colormanagement_imbuf_for_write(ibuf_arr[2], true, false, &scene->view_settings,
 				                                    &scene->display_settings, &imf);
 
-				if (stamp)
-					ok = BKE_imbuf_write_stamp(scene, rr, ibuf_arr[2], name, &rd->im_format);
-				else
-					ok = BKE_imbuf_write(ibuf_arr[2], name, &imf);
-
-				printf("Saved: %s\n", name);
+				ok = render_imbuf_write_stamp_test(scene, rr, ibuf_arr[2], name, &rd->im_format, stamp);
 			}
 
 			/* imbuf knows which rects are not part of ibuf */
diff --git a/source/blender/render/intern/source/render_result.c b/source/blender/render/intern/source/render_result.c
index 19b049ee1da..c89adc4a814 100644
--- a/source/blender/render/intern/source/render_result.c
+++ b/source/blender/render/intern/source/render_result.c
@@ -32,6 +32,7 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
+#include <errno.h>
 
 #include "MEM_guardedalloc.h"
 
@@ -1134,6 +1135,8 @@ bool RE_WriteRenderResult(ReportList *reports, RenderResult *rr, const char *fil
 		}
 	}
 
+	errno = 0;
+
 	BLI_make_existing_file(filename);
 
 	if (IMB_exr_begin_write(exrhandle, filename, width, height, compress, rr->stamp_data)) {
@@ -1142,7 +1145,7 @@ bool RE_WriteRenderResult(ReportList *reports, RenderResult *rr, const char *fil
 	}
 	else {
 		/* TODO, get the error from openexr's exception */
-		BKE_report(reports, RPT_ERROR, "Error writing render result (see console)");
+		BKE_reportf(reports, RPT_ERROR, "Error writing render result, %s (see console)", strerror(errno));
 		success = false;
 	}