Improve the sftp seek functions.

git-svn-id: svn+ssh://svn.berlios.de/svnroot/repos/libssh/trunk@605 7dcaeef0-15fb-0310-b436-a5af3365683c

include/libssh/sftp.h

@@ -443,8 +443,10 @@ ssize_t sftp_write(SFTP_FILE *file, const void *buf, size_t count);
  * @param file         Open sftp file handle to seek in.
  *
  * @param new_offset   Offset in bytes to seek.
+ *
+ * @return             0 on success, < 0 on error.
  */
-void sftp_seek(SFTP_FILE *file, int new_offset);
+int sftp_seek(SFTP_FILE *file, u32 new_offset);
 
 /**
  * @brief Seek to a specific location in a file. This is the
@@ -453,8 +455,10 @@ void sftp_seek(SFTP_FILE *file, int new_offset);
  * @param file         Open sftp file handle to seek in.
  *
  * @param new_offset   Offset in bytes to seek.
+ *
+ * @return             0 on success, < 0 on error.
  */
-void sftp_seek64(SFTP_FILE *file, u64 new_offset);
+int sftp_seek64(SFTP_FILE *file, u64 new_offset);
 
 /**
  * @brief Report current byte position in file.

libssh/sftp.c

@@ -1744,12 +1744,24 @@ ssize_t sftp_write(SFTP_FILE *file, const void *buf, size_t count) {
 }
 
 /* Seek to a specific location in a file. */
-void sftp_seek(SFTP_FILE *file, int new_offset){
-    file->offset=new_offset;
+int sftp_seek(SFTP_FILE *file, u32 new_offset) {
+  if (file == NULL) {
+    return -1;
+  }
+
+  file->offset = new_offset;
+
+  return 0;
 }
 
-void sftp_seek64(SFTP_FILE *file, u64 new_offset){
-	file->offset=new_offset;
+int sftp_seek64(SFTP_FILE *file, u64 new_offset) {
+  if (file == NULL) {
+    return -1;
+  }
+
+  file->offset = new_offset;
+
+  return 0;
 }
 
 /* Report current byte position in file. */