From 7f2dfaa5b41905e31c3df92e9dda6a1db7b49ff6 Mon Sep 17 00:00:00 2001
From: curt <curt>
Date: Sat, 24 Sep 2005 12:28:14 +0000
Subject: [PATCH] Add eof() support to SGIOChannel/SGFile.

---
 simgear/io/iochannel.cxx | 6 ++++++
 simgear/io/iochannel.hxx | 8 ++++++++
 simgear/io/sg_file.cxx   | 4 ++--
 3 files changed, 16 insertions(+), 2 deletions(-)

diff --git a/simgear/io/iochannel.cxx b/simgear/io/iochannel.cxx
index cc6292b3..994aa89f 100644
--- a/simgear/io/iochannel.cxx
+++ b/simgear/io/iochannel.cxx
@@ -70,3 +70,9 @@ int SGIOChannel::writestring( const char *str ) {
 bool SGIOChannel::close() {
     return false;
 }
+
+
+// dummy eof routine
+bool SGIOChannel::eof() {
+    return false;
+}
diff --git a/simgear/io/iochannel.hxx b/simgear/io/iochannel.hxx
index 2cfa5477..48c782a1 100644
--- a/simgear/io/iochannel.hxx
+++ b/simgear/io/iochannel.hxx
@@ -152,6 +152,14 @@ public:
      */
     virtual bool close();
 
+    /**
+     * The eof() method returns true if end of file has been reached
+     * in a context where that makes sense.  Otherwise it returns
+     * false.
+     * @return result of eof check
+     */
+    virtual bool eof();
+
     inline void set_type( SGChannelType t ) { type = t; }
     inline SGChannelType get_type() const { return type; }
 
diff --git a/simgear/io/sg_file.cxx b/simgear/io/sg_file.cxx
index 079fefec..0caf3f4a 100644
--- a/simgear/io/sg_file.cxx
+++ b/simgear/io/sg_file.cxx
@@ -80,7 +80,7 @@ bool SGFile::open( const SGProtocolDir d ) {
 int SGFile::read( char *buf, int length ) {
     // read a chunk
     ssize_t result = ::read( fp, buf, length );
-    if ( result == 0 ) {
+    if ( length > 0 && result == 0 ) {
         eof_flag = true;
     }
     return result;
@@ -94,7 +94,7 @@ int SGFile::readline( char *buf, int length ) {
 
     // read a chunk
     ssize_t result = ::read( fp, buf, length );
-    if ( result == 0 ) {
+    if ( length > 0 && result == 0 ) {
         eof_flag = true;
     }
 
-- 
2.39.5