Update config.{guess,sub}, timestamps 2023-01-01,2023-01-21

[libpcap] / portability.h

diff --git a/portability.h b/portability.h
index 47c9f470a92cf6b4cccb874ce865c2c0b737e98b..84d0778a5c77cb6ec97048e265d8ab8dde77c0a2 100644 (file)
--- a/portability.h
+++ b/portability.h
@@ -38,6 +38,7 @@
  * Helpers for portability between Windows and UN*X and between different
  * flavors of UN*X.
  */
+#include <stdarg.h>    /* we declare varargs functions on some platforms */
 
 #include "pcap/funcattrs.h"
 
@@ -51,7 +52,7 @@ extern "C" {
   #if defined(_MSC_VER) || defined(__MINGW32__)
     /*
      * strncat_s() is supported at least back to Visual
-     * Studio 2005.
+     * Studio 2005; we require Visual Studio 2015 or later.
      */
     #define pcap_strlcat(x, y, z) \
        strncat_s((x), (z), (y), _TRUNCATE)
@@ -69,7 +70,7 @@ extern "C" {
   #if defined(_MSC_VER) || defined(__MINGW32__)
     /*
      * strncpy_s() is supported at least back to Visual
-     * Studio 2005.
+     * Studio 2005; we require Visual Studio 2015 or later.
      */
     #define pcap_strlcpy(x, y, z) \
        strncpy_s((x), (z), (y), _TRUNCATE)
@@ -82,8 +83,6 @@ extern "C" {
 #endif
 
 #ifdef _MSC_VER
-  #define isascii      _isascii
-
   /*
    * If <crtdbg.h> has been included, and _DEBUG is defined, and
    * __STDC__ is zero, <crtdbg.h> will define strdup() to call
@@ -96,40 +95,47 @@ extern "C" {
 #endif
 
 /*
- * On Windows, snprintf(), with that name and with C99 behavior - i.e.,
- * guaranteeing that the formatted string is null-terminated - didn't
- * appear until Visual Studio 2015.  Prior to that, the C runtime had
- * only _snprintf(), which *doesn't* guarantee that the string is
- * null-terminated if it is truncated due to the buffer being too
- * small.  We therefore can't just define snprintf to be _snprintf
- * and define vsnprintf to be _vsnprintf, as we're relying on null-
- * termination of strings in all cases.
- *
- * We also want to allow this to be built with versions of Visual Studio
- * prior to VS 2015, so we can't rely on snprintf() being present.
- *
- * And we want to make sure that, if we support plugins in the future,
- * a routine with C99 snprintf() behavior will be available to them.
- * We also don't want it to collide with the C library snprintf() if
- * there is one.
- *
- * So we make pcap_snprintf() and pcap_vsnprintf() available, either by
- * #defining them to be snprintf or vsnprintf, respectively, or by
- * defining our own versions and exporting them.
+ * We want asprintf(), for some cases where we use it to construct
+ * dynamically-allocated variable-length strings; it's present on
+ * some, but not all, platforms.
  */
-#ifdef HAVE_SNPRINTF
-#define pcap_snprintf snprintf
+#ifdef HAVE_ASPRINTF
+#define pcap_asprintf asprintf
 #else
-extern int pcap_snprintf(char *, size_t, PCAP_FORMAT_STRING(const char *), ...)
-    PCAP_PRINTFLIKE(3, 4);
+extern int pcap_asprintf(char **, PCAP_FORMAT_STRING(const char *), ...)
+    PCAP_PRINTFLIKE(2, 3);
 #endif
 
-#ifdef HAVE_VSNPRINTF
-#define pcap_vsnprintf vsnprintf
+#ifdef HAVE_VASPRINTF
+#define pcap_vasprintf vasprintf
 #else
-extern int pcap_vsnprintf(char *, size_t, const char *, va_list ap);
+extern int pcap_vasprintf(char **, const char *, va_list ap);
 #endif
 
+/* For Solaris before 11. */
+#ifndef timeradd
+#define timeradd(a, b, result)                       \
+  do {                                               \
+    (result)->tv_sec = (a)->tv_sec + (b)->tv_sec;    \
+    (result)->tv_usec = (a)->tv_usec + (b)->tv_usec; \
+    if ((result)->tv_usec >= 1000000) {              \
+      ++(result)->tv_sec;                            \
+      (result)->tv_usec -= 1000000;                  \
+    }                                                \
+  } while (0)
+#endif /* timeradd */
+#ifndef timersub
+#define timersub(a, b, result)                       \
+  do {                                               \
+    (result)->tv_sec = (a)->tv_sec - (b)->tv_sec;    \
+    (result)->tv_usec = (a)->tv_usec - (b)->tv_usec; \
+    if ((result)->tv_usec < 0) {                     \
+      --(result)->tv_sec;                            \
+      (result)->tv_usec += 1000000;                  \
+    }                                                \
+  } while (0)
+#endif /* timersub */
+
 #ifdef HAVE_STRTOK_R
   #define pcap_strtok_r        strtok_r
 #else