From fa8e3f3f20f2f2dc5d160fb70b747568a7b4f1cf Mon Sep 17 00:00:00 2001
From: ZyX <kp-pav@yandex.ru>
Date: Sat, 25 Jul 2015 13:34:57 +0300
Subject: [PATCH] shada: Only check errno if read/write returned -1

According to the manual (POSIX) this is the only case when errno is set by these
functions. This is needed because some functions (e.g. buflist_new) leave errno
set to non-zero value under some conditions (e.g. when opening non-existing
files).
---
 src/nvim/shada.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/nvim/shada.c b/src/nvim/shada.c
index da107ef38b..d7b3e27550 100644
--- a/src/nvim/shada.c
+++ b/src/nvim/shada.c
@@ -525,7 +525,7 @@ static ptrdiff_t read_file(ShaDaReadDef *const sd_reader, void *const dest,
       sd_reader->fpos += (uintmax_t) cur_read_bytes;
       assert(read_bytes <= size);
     }
-    if (errno) {
+    if (cur_read_bytes < 0) {
       if (errno == EINTR || errno == EAGAIN) {
         errno = 0;
         continue;
@@ -576,7 +576,7 @@ static ptrdiff_t write_file(ShaDaWriteDef *const sd_writer,
     if (cur_written_bytes > 0) {
       written_bytes += (size_t) cur_written_bytes;
     }
-    if (errno) {
+    if (cur_written_bytes < 0) {
       if (errno == EINTR || errno == EAGAIN) {
         errno = 0;
         continue;