From: Matthew Fernandez <matthew.fernandez@gmail.com>
Date: Sat, 5 Mar 2022 23:18:13 +0000 (-0800)
Subject: DevIL plugin: only save output if image processing succeeded
X-Git-Tag: 4.0.0~190^2
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=fcddcfdec5496bb447875aa18b9d3ce8d23d5e41;p=graphviz

DevIL plugin: only save output if image processing succeeded

As suggested during the review of !2488.¹

¹ https://gitlab.com/graphviz/graphviz/-/merge_requests/2488
---

diff --git a/plugin/devil/gvdevice_devil.c b/plugin/devil/gvdevice_devil.c
index 7f8922f2f..74d29e8eb 100644
--- a/plugin/devil/gvdevice_devil.c
+++ b/plugin/devil/gvdevice_devil.c
@@ -34,7 +34,6 @@ Y_inv ( unsigned int width, unsigned int height, char *data)
 static void devil_format(GVJ_t * job)
 {
     ILuint	ImgId;
-    ILenum	Error;
 
     // Check if the shared lib's version matches the executable's version.
     if (ilGetInteger(IL_VERSION_NUM) < IL_VERSION ||
@@ -61,9 +60,15 @@ static void devil_format(GVJ_t * job)
     		IL_BGRA,	// Format
     		IL_UNSIGNED_BYTE,// Type
     		job->imagedata);
-    
-    // output to the provided open file handle
-    ilSaveF((ILenum)job->device.id, job->output_file);
+
+    // check the last step succeeded
+    ILenum Error = ilGetError();
+    if (Error == 0) {
+    	// output to the provided open file handle
+    	ilSaveF((ILenum)job->device.id, job->output_file);
+    } else {
+    	fprintf(stderr, "Error: %s\n", iluErrorString(Error));
+    }
     
     // We're done with the image, so delete it.
     ilDeleteImages(1, &ImgId);