Use internal dtoa/strtod for double conversion

The internal Lua CJSON dtoa/strtod routines have locale support
disabled. This avoids problems under locales with comma decimal
separators.

Build changes:
- CMake: Check for big endian architectures
- Makefile: Provide option to build with dtoa.c

Modifications to dtoa.c:
- Include locale dtoa_config.h configuration
- Rename Infinity/NaN to inf/nan to match common C libraries
- Rename strtod() -> internal_strtod() to prevent conflict with libc
  function

Modifications to g_fmt.c:
- Return output string length (instead of original buffer pointer)
- Provide precision as an argument to g_fmt()
- Silence compilations warnings from vendor source
  - while(a = b)
  - Unused label "done:"
- Only swap to scientific notation when once the number of decimal
  digits required exceeds the precision available. This matches
  standard printf format %g.
- Display a "0" in front of numbers < 1.

1 files changed, 6 insertions, 0 deletions

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 8d8a420..ffc718b 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -11,6 +11,12 @@ set(CMAKE_BUILD_TYPE Release)
 find_package(Lua51 REQUIRED)
 include_directories(${LUA_INCLUDE_DIR})
 
+include(TestBigEndian)
+TEST_BIG_ENDIAN(BIG_ENDIAN)
+if(HAVE_BIG_ENDIAN)
+    add_definitions(-DIEEE_BIG_ENDIAN)
+endif()
+
 # Handle platforms missing isinf() macro (Eg, some Solaris systems).
 include(CheckSymbolExists)
 CHECK_SYMBOL_EXISTS(isinf math.h HAVE_ISINF)