From 951870b18978eab89391f43c3c5b85e0700eb198 Mon Sep 17 00:00:00 2001
From: Chris Robinson <chris.kcat@gmail.com>
Date: Tue, 5 Aug 2014 05:05:05 -0700
Subject: [PATCH] Enable large file support

---
 CMakeLists.txt                  | 10 ++++++++++
 cmake/CheckFileOffsetBits.c     |  9 +++++++++
 cmake/CheckFileOffsetBits.cmake | 39 +++++++++++++++++++++++++++++++++++++++
 3 files changed, 58 insertions(+)
 create mode 100644 cmake/CheckFileOffsetBits.c
 create mode 100644 cmake/CheckFileOffsetBits.cmake

diff --git a/CMakeLists.txt b/CMakeLists.txt
index da3f160f..278c70c6 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -20,6 +20,7 @@ INCLUDE(CheckSymbolExists)
 INCLUDE(CheckCCompilerFlag)
 INCLUDE(CheckCSourceCompiles)
 INCLUDE(CheckTypeSize)
+include(CheckFileOffsetBits)
 
 
 SET(CMAKE_ALLOW_LOOSE_LOOP_CONSTRUCTS TRUE)
@@ -36,6 +37,15 @@ ELSE()
     SET(CMAKE_REQUIRED_FLAGS "${CMAKE_REQUIRED_FLAGS} -D_GNU_SOURCE=1 -D_POSIX_C_SOURCE=200809L -D_XOPEN_SOURCE=700")
 ENDIF()
 
+# Set defines for large file support
+CHECK_FILE_OFFSET_BITS()
+IF(_FILE_OFFSET_BITS)
+    ADD_DEFINITIONS(-D_FILE_OFFSET_BITS=${_FILE_OFFSET_BITS})
+    SET(CMAKE_REQUIRED_FLAGS "${CMAKE_REQUIRED_FLAGS} -D_FILE_OFFSET_BITS=${_FILE_OFFSET_BITS}")
+ENDIF()
+ADD_DEFINITIONS(-D_LARGEFILE_SOURCE -D_LARGE_FILES)
+SET(CMAKE_REQUIRED_FLAGS "${CMAKE_REQUIRED_FLAGS} -D_LARGEFILE_SOURCE -D_LARGE_FILES")
+
 
 OPTION(ALSOFT_DLOPEN  "Check for the dlopen API for loading optional libs"  ON)
 
diff --git a/cmake/CheckFileOffsetBits.c b/cmake/CheckFileOffsetBits.c
new file mode 100644
index 00000000..de98296e
--- /dev/null
+++ b/cmake/CheckFileOffsetBits.c
@@ -0,0 +1,9 @@
+#include <sys/types.h>
+
+#define KB ((off_t)(1024))
+#define MB ((off_t)(KB*1024))
+#define GB ((off_t)(MB*1024))
+int tb[((GB+GB+GB) > GB) ? 1 : -1];
+
+int main()
+{ return 0; }
diff --git a/cmake/CheckFileOffsetBits.cmake b/cmake/CheckFileOffsetBits.cmake
new file mode 100644
index 00000000..8b549b69
--- /dev/null
+++ b/cmake/CheckFileOffsetBits.cmake
@@ -0,0 +1,39 @@
+# - Check if the _FILE_OFFSET_BITS macro is needed for large files
+# CHECK_FILE_OFFSET_BITS()
+#
+# The following variables may be set before calling this macro to
+# modify the way the check is run:
+#
+#  CMAKE_REQUIRED_FLAGS = string of compile command line flags
+#  CMAKE_REQUIRED_DEFINITIONS = list of macros to define (-DFOO=bar)
+#  CMAKE_REQUIRED_INCLUDES = list of include directories
+# Copyright (c) 2009, Chris Robinson
+#
+# Redistribution and use is allowed according to the terms of the LGPL license.
+
+
+MACRO(CHECK_FILE_OFFSET_BITS)
+
+  IF(NOT DEFINED _FILE_OFFSET_BITS)
+    MESSAGE(STATUS "Checking _FILE_OFFSET_BITS for large files")
+    TRY_COMPILE(__WITHOUT_FILE_OFFSET_BITS_64
+      ${CMAKE_BINARY_DIR}
+      ${CMAKE_SOURCE_DIR}/cmake/CheckFileOffsetBits.c
+      COMPILE_DEFINITIONS ${CMAKE_REQUIRED_DEFINITIONS})
+    IF(NOT __WITHOUT_FILE_OFFSET_BITS_64)
+      TRY_COMPILE(__WITH_FILE_OFFSET_BITS_64
+        ${CMAKE_BINARY_DIR}
+        ${CMAKE_SOURCE_DIR}/cmake/CheckFileOffsetBits.c
+        COMPILE_DEFINITIONS ${CMAKE_REQUIRED_DEFINITIONS} -D_FILE_OFFSET_BITS=64)
+    ENDIF(NOT __WITHOUT_FILE_OFFSET_BITS_64)
+
+    IF(NOT __WITHOUT_FILE_OFFSET_BITS_64 AND __WITH_FILE_OFFSET_BITS_64)
+      SET(_FILE_OFFSET_BITS 64 CACHE INTERNAL "_FILE_OFFSET_BITS macro needed for large files")
+      MESSAGE(STATUS "Checking _FILE_OFFSET_BITS for large files - 64")
+    ELSE(NOT __WITHOUT_FILE_OFFSET_BITS_64 AND __WITH_FILE_OFFSET_BITS_64)
+      SET(_FILE_OFFSET_BITS "" CACHE INTERNAL "_FILE_OFFSET_BITS macro needed for large files")
+      MESSAGE(STATUS "Checking _FILE_OFFSET_BITS for large files - not needed")
+    ENDIF(NOT __WITHOUT_FILE_OFFSET_BITS_64 AND __WITH_FILE_OFFSET_BITS_64)
+  ENDIF(NOT DEFINED _FILE_OFFSET_BITS)
+
+ENDMACRO(CHECK_FILE_OFFSET_BITS)
\ No newline at end of file
-- 
2.11.4.GIT