Handle older OSes without DLT_PRISM_HEADER/DLT_AIRONET_HEADER/DLT_PPI.

[libpcap] / pcap / compiler-tests.h

diff --git a/pcap/compiler-tests.h b/pcap/compiler-tests.h
index a7ae2521270efe4245570c50e90b6fc3328615fa..ea5962c7bf5e6849521167db95274ec81f06576b 100644 (file)
--- a/pcap/compiler-tests.h
+++ b/pcap/compiler-tests.h
@@ -35,7 +35,6 @@
 #ifndef lib_pcap_compiler_tests_h
 #define lib_pcap_compiler_tests_h
 
-
 /*
  * This was introduced by Clang:
  *
@@ -54,40 +53,50 @@
   #define __has_attribute(x) 0
 #endif
 
+/*
+ * Note that the C90 spec's "6.8.1 Conditional inclusion" and the
+ * C99 spec's and C11 spec's "6.10.1 Conditional inclusion" say:
+ *
+ *    Prior to evaluation, macro invocations in the list of preprocessing
+ *    tokens that will become the controlling constant expression are
+ *    replaced (except for those macro names modified by the defined unary
+ *    operator), just as in normal text.  If the token "defined" is
+ *    generated as a result of this replacement process or use of the
+ *    "defined" unary operator does not match one of the two specified
+ *    forms prior to macro replacement, the behavior is undefined.
+ *
+ * so you shouldn't use defined() in a #define that's used in #if or
+ * #elif.  Some versions of Clang, for example, will warn about this.
+ *
+ * Instead, we check whether the pre-defined macros for particular
+ * compilers are defined and, if not, define the "is this version XXX
+ * or a later version of this compiler" macros as 0.
+ */
+
 /*
  * Check whether this is GCC major.minor or a later release, or some
  * compiler that claims to be "just like GCC" of that version or a
  * later release.
  */
 
-#if defined(__GNUC__) && (__GNUC__ > 2 || (__GNUC__ == 2 && __GNUC_MINOR__ >= 3))
-#define PCAP_IS_AT_LEAST_GNUC_VERSION_2_3 1
+#if ! defined(__GNUC__)
+#define PCAP_IS_AT_LEAST_GNUC_VERSION(major, minor) 0
 #else
-#define PCAP_IS_AT_LEAST_GNUC_VERSION_2_3 0
+#define PCAP_IS_AT_LEAST_GNUC_VERSION(major, minor) \
+       (__GNUC__ > (major) || \
+        (__GNUC__ == (major) && __GNUC_MINOR__ >= (minor)))
 #endif
 
-#if defined(__GNUC__) && (__GNUC__ > 2 || (__GNUC__ == 2 && __GNUC_MINOR__ >= 5))
-#define PCAP_IS_AT_LEAST_GNUC_VERSION_2_5 1
-#else
-#define PCAP_IS_AT_LEAST_GNUC_VERSION_2_5 0
-#endif
-
-#if defined(__GNUC__) && (__GNUC__ > 3 || (__GNUC__ == 3 && __GNUC_MINOR__ >= 1))
-#define PCAP_IS_AT_LEAST_GNUC_VERSION_3_1 1
-#else
-#define PCAP_IS_AT_LEAST_GNUC_VERSION_3_1 0
-#endif
-
-#if defined(__GNUC__) && (__GNUC__ > 3 || (__GNUC__ == 3 && __GNUC_MINOR__ >= 4))
-#define PCAP_IS_AT_LEAST_GNUC_VERSION_3_4 1
-#else
-#define PCAP_IS_AT_LEAST_GNUC_VERSION_3_4 0
-#endif
+/*
+ * Check whether this is Clang major.minor or a later release.
+ */
 
-#if defined(__GNUC__) && (__GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 5))
-#define PCAP_IS_AT_LEAST_GNUC_VERSION_4_5 1
+#if !defined(__clang__)
+#define PCAP_IS_AT_LEAST_CLANG_VERSION(major, minor) 0
 #else
-#define PCAP_IS_AT_LEAST_GNUC_VERSION_4_5 0
+#define PCAP_IS_AT_LEAST_CLANG_VERSION(major, minor) \
+       (__clang_major__ > (major) || \
+        (__clang_major__ == (major) && __clang_minor__ >= (minor)))
 #endif
 
 /*
@@ -107,27 +116,16 @@
  * for a partial mapping, which we assume continues for later
  * 12.x product releases.
  */
+
+#if ! defined(__SUNPRO_C)
+#define PCAP_IS_AT_LEAST_SUNC_VERSION(major,minor) 0
+#else
 #define PCAP_SUNPRO_VERSION_TO_BCD(major, minor) \
        (((minor) >= 10) ? \
            (((major) << 12) | (((minor)/10) << 8) | (((minor)%10) << 4)) : \
            (((major) << 8) | ((minor) << 4)))
-
-#if defined(__SUNPRO_C) && __SUNPRO_C >= PCAP_SUNPRO_VERSION_TO_BCD(5, 5)
-#define PCAP_IS_AT_LEAST_SUNC_VERSION_5_5 1
-#else
-#define PCAP_IS_AT_LEAST_SUNC_VERSION_5_5 0
-#endif
-
-#if defined(__SUNPRO_C) && __SUNPRO_C >= PCAP_SUNPRO_VERSION_TO_BCD(5, 9)
-#define PCAP_IS_AT_LEAST_SUNC_VERSION_5_9 1
-#else
-#define PCAP_IS_AT_LEAST_SUNC_VERSION_5_9 0
-#endif
-
-#if defined(__SUNPRO_C) && __SUNPRO_C >= PCAP_SUNPRO_VERSION_TO_BCD(5, 13)
-#define PCAP_IS_AT_LEAST_SUNC_VERSION_5_13 1
-#else
-#define PCAP_IS_AT_LEAST_SUNC_VERSION_5_13 0
+#define PCAP_IS_AT_LEAST_SUNC_VERSION(major,minor) \
+       (__SUNPRO_C >= PCAP_SUNPRO_VERSION_TO_BCD((major), (minor)))
 #endif
 
 /*
@@ -137,16 +135,11 @@
  * upper 8 bits and the minor version in the lower 8 bits.
  */
 
-#if defined(__xlC__) && __xlC__ >= ((10 << 8) | 1)
-#define PCAP_IS_AT_LEAST_XL_C_VERSION_10_1 1
-#else
-#define PCAP_IS_AT_LEAST_XL_C_VERSION_10_1 0
-#endif
-
-#if defined(__xlC__) && __xlC__ >= ((12 << 8) | 0)
-#define PCAP_IS_AT_LEAST_XL_C_VERSION_12_0 1
+#if ! defined(__xlC__)
+#define PCAP_IS_AT_LEAST_XL_C_VERSION(major,minor) 0
 #else
-#define PCAP_IS_AT_LEAST_XL_C_VERSION_12_0 0
+#define PCAP_IS_AT_LEAST_XL_C_VERSION(major, minor) \
+       (__xlC__ >= (((major) << 8) | (minor)))
 #endif
 
 /*
@@ -160,10 +153,11 @@
  * number, and add two digits of patch.)
  */
 
-#if defined(__HP_aCC) && (__HP_aCC >= (6*10000 + 10*100))
-#define PCAP_IS_AT_LEAST_HP_C_VERSION_6_10 1
+#if ! defined(__HP_aCC)
+#define PCAP_IS_AT_LEAST_HP_C_VERSION(major,minor) 0
 #else
-#define PCAP_IS_AT_LEAST_HP_C_VERSION_6_10 0
+#define PCAP_IS_AT_LEAST_HP_C_VERSION(major,minor) \
+       (__HP_aCC >= ((major)*10000 + (minor)*100))
 #endif
 
-#endif /* lib_pcap_funcattrs_h */
+#endif /* lib_pcap_compiler_tests_h */