From a148b23a22709a45647fd07ce95db9147217a061 Mon Sep 17 00:00:00 2001
From: Kartik Agaram <vc@akkartik.com>
Date: Sun, 25 Oct 2020 18:45:11 -0700
Subject: 7101 - tile: remove quotes when evaluating strings

This found several bugs due to me not checking for null strings.
---
 108write.subx | 3 +++
 1 file changed, 3 insertions(+)

(limited to '108write.subx')

diff --git a/108write.subx b/108write.subx
index 988e21db..84060c62 100644
--- a/108write.subx
+++ b/108write.subx
@@ -25,6 +25,9 @@ write:  # f: fd or (addr stream byte), s: (addr array byte)
     # . prologue
     55/push-ebp
     89/copy                         3/mod/direct    5/rm32/ebp    .           .             .           4/r32/esp   .               .                 # copy esp to ebp
+    # if (s == 0) return
+    81          7/subop/compare     1/mod/*+disp8   5/rm32/ebp    .           .             .           .           0xc/disp8       0/imm32           # compare *(ebp+12)
+    74/jump-if-=  $write:end/disp8
     # if (f < 0x08000000) _write(f, s) and return  # f can't be a user-mode address, so treat it as a kernel file descriptor
     81          7/subop/compare     1/mod/*+disp8   5/rm32/ebp    .           .             .           .           8/disp8         0x08000000/imm32  # compare *(ebp+8)
     73/jump-if-addr>=  $write:fake/disp8
-- 
cgit 1.4.1-2-gfad0