From abe0c14301f6f95df6a2563d66674aadd4fc456f Mon Sep 17 00:00:00 2001
From: joevt <joevt@shaw.ca>
Date: Sat, 4 Nov 2023 22:19:39 -0700
Subject: [PATCH] scsibus: push_data of zero bytes is ok.

It just means the data hasn't been put on the fifo yet.
---
 devices/common/scsi/scsibus.cpp | 11 +++++++++--
 1 file changed, 9 insertions(+), 2 deletions(-)

diff --git a/devices/common/scsi/scsibus.cpp b/devices/common/scsi/scsibus.cpp
index 6f4d3b3..75de5cd 100644
--- a/devices/common/scsi/scsibus.cpp
+++ b/devices/common/scsi/scsibus.cpp
@@ -263,11 +263,18 @@ bool ScsiBus::pull_data(const int id, uint8_t* dst_ptr, const int size)
 
 bool ScsiBus::push_data(const int id, const uint8_t* src_ptr, const int size)
 {
-    if (!this->devices[id]->rcv_data(src_ptr, size)) {
-        LOG_F(ERROR, "ScsiBus: error while transferring I->T data!");
+    if (!this->devices[id]) {
+        LOG_F(ERROR, "%s: no device %d for push_data %d bytes", this->get_name().c_str(), id, size);
         return false;
     }
 
+    if (!this->devices[id]->rcv_data(src_ptr, size)) {
+        if (size) {
+            LOG_F(ERROR, "%s: error while transferring I->T data!", this->get_name().c_str());
+            return false;
+        }
+    }
+
     return true;
 }