[groff] 09/13: [grn]: Emit error when failing to open file.

[G. Branden Robinson]

gbranden pushed a commit to branch master
in repository groff.

commit 646539bc119e7dd838851deb77877c64d82241e7
Author: G. Branden Robinson <g.branden.robinson@gmail.com>
AuthorDate: Fri Apr 15 08:32:44 2022 +1000

    [grn]: Emit error when failing to open file.
    
    * src/preproc/grn/main.cpp (conv): Throw an error diagnostic when
      failing to open a Gremlin picture file.
---
 ChangeLog                | 5 +++++
 src/preproc/grn/main.cpp | 4 +++-
 2 files changed, 8 insertions(+), 1 deletion(-)

diff --git a/ChangeLog b/ChangeLog
index 55aacc86..fe3d227a 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+2022-04-14  G. Branden Robinson <g.branden.robinson@gmail.com>
+
+       * src/preproc/grn/main.cpp (conv): Throw an error diagnostic
+       when failing to open a Gremlin picture file.
+
 2022-04-14  G. Branden Robinson <g.branden.robinson@gmail.com>
 
        [man]: Fix extraneous space when `ME` or `UE` given extraneous
diff --git a/src/preproc/grn/main.cpp b/src/preproc/grn/main.cpp
index c4a57a49..fcc22896 100644
--- a/src/preproc/grn/main.cpp
+++ b/src/preproc/grn/main.cpp
@@ -567,8 +567,10 @@ conv(FILE *fp,
       }
       char *path;
       gfp = macro_path.open_file(gremlinfile, &path);
-      if (!gfp)
+      if (0 /* nullptr */ == gfp) {
+       error("cannot open picture file '%1'", gremlinfile);
        return;
+      }
       PICTURE = DBRead(gfp);   /* read picture file */
       fclose(gfp);
       free(path);