Tweak use of return_error to be more useful.

In these two instances, the existing code is calling
return_error(gs_error_rangecheck), even when the functions
are being called to check what the required size is (i.e.
when gs_error_rangecheck is not actually an error).

Tweak the code so that we no longer hit breakpoints in
gs_note_error for such cases.

2 files changed, 9 insertions, 3 deletions

diff --git a/base/gsovrc.c b/base/gsovrc.c
index 16cd729ce..80f43ae33 100644
--- a/base/gsovrc.c
+++ b/base/gsovrc.c
@@ -181,8 +181,11 @@ c_overprint_write(const gs_composite_t * pct, byte * data, uint * psize, gx_devi
 
     /* check for overflow */
     *psize = used;
-    if (used > avail)
-        return_error(gs_error_rangecheck);
+    if (used > avail) {
+        if (avail != 0)
+            return_error(gs_error_rangecheck);
+        return gs_error_rangecheck;
+    }
     data[0] = flags;
     if_debug2m('v', ((const gx_device *)cdev)->memory, "[v]c_overprint_write(%d), drawn_comps=0x%x\n",
                flags, pparams->drawn_comps);
diff --git a/base/gxdcolor.c b/base/gxdcolor.c
index 20116fd88..c0f0c1d45 100644
--- a/base/gxdcolor.c
+++ b/base/gxdcolor.c
@@ -1146,8 +1146,11 @@ gx_dc_write_color(
 
     /* check for adequate space */
     if (*psize < num_bytes) {
+        uint x = *psize;
         *psize = num_bytes;
-        return_error(gs_error_rangecheck);
+        if (x != 0)
+            return_error(gs_error_rangecheck);
+        return gs_error_rangecheck;
     }
     *psize = num_bytes;