Add work around for missing isinf() on Solaris

Some versions of Solaris (Eg, Solaris 11 / GCC 3.4.3) are missing
isinf(). Provide a work around when MISSING_ISINF is defined.

Reported by: Zhang "agentzh" Yichun <agentzh@gmail.com>

3 files changed, 10 insertions, 0 deletions

diff --git a/Makefile b/Makefile
index cfc7a74..d34ff6d 100644
--- a/Makefile
+++ b/Makefile
@@ -15,6 +15,9 @@ LDFLAGS +=         -shared
 LUA_INCLUDE_DIR ?= $(PREFIX)/include
 LUA_LIB_DIR ?=     $(PREFIX)/lib/lua/$(LUA_VERSION)
 
+# Some versions of Solaris are missing isinf(). Add -DMISSING_ISINF to
+# CFLAGS to work around this bug.
+
 #CFLAGS ?=          -g -Wall -pedantic -fno-inline
 CFLAGS ?=          -g -O3 -Wall -pedantic
 override CFLAGS += -fpic -I$(LUA_INCLUDE_DIR) -DVERSION=\"$(CJSON_VERSION)\"
diff --git a/README b/README
index b849b92..d080ce3 100644
--- a/README
+++ b/README
@@ -51,6 +51,9 @@ Review and update the included Makefile to suit your platform. Then:
   OR
   # cp cjson.so [your_module_directory]
 
+Note: Some Solaris platforms are missing isinf(). You can work around
+      this bug by adding -DMISSING_ISINF to CFLAGS in the Makefile.
+
 
 RPM
 ---
diff --git a/lua_cjson.c b/lua_cjson.c
index b46e915..076c56f 100644
--- a/lua_cjson.c
+++ b/lua_cjson.c
@@ -44,6 +44,10 @@
 
 #include "strbuf.h"
 
+#ifdef MISSING_ISINF
+#define isinf(x) (!isnan(x) && isnan((x) - (x)))
+#endif
+
 #define DEFAULT_SPARSE_CONVERT 0
 #define DEFAULT_SPARSE_RATIO 2
 #define DEFAULT_SPARSE_SAFE 10