#include <errno.h>
+#include "compiler-tests.h"
+
+#include "varattrs.h"
+
/*
* Get the C99 types, and the PRI[doux]64 format strings, defined.
*/
#endif
#ifdef _MSC_VER
-#define stat _stat
-#define open _open
-#define fstat _fstat
-#define read _read
-#define close _close
-#define O_RDONLY _O_RDONLY
+ /*
+ * Microsoft tries to avoid polluting the C namespace with UN*Xisms,
+ * by adding a preceding underscore; we *want* the UN*Xisms, so add
+ * #defines to let us use them.
+ */
+ #define isascii __isascii
+ #define isatty _isatty
+ #define stat _stat
+ #define strdup _strdup
+ #define open _open
+ #define fstat _fstat
+ #define read _read
+ #define close _close
+ #define O_RDONLY _O_RDONLY
+
+ /*
+ * If <crtdbg.h> has been included, and _DEBUG is defined, and
+ * __STDC__ is zero, <crtdbg.h> will define strdup() to call
+ * _strdup_dbg(). So if it's already defined, don't redefine
+ * it.
+ */
+ #ifndef strdup
+ #define strdup _strdup
+ #endif
#endif /* _MSC_VER */
/*
#endif /* caddr_t */
#define MAXHOSTNAMELEN 64
-#define snprintf _snprintf
-#define vsnprintf _vsnprintf
#else /* _WIN32 */
#endif /* _WIN32 */
-#ifndef HAVE___ATTRIBUTE__
-#define __attribute__(x)
-#endif
+/*
+ * Function attributes, for various compilers.
+ */
+#include "funcattrs.h"
/*
- * Used to declare a structure unaligned, so that the C compiler,
- * if necessary, generates code that doesn't assume alignment.
- * This is required because there is no guarantee that the packet
- * data we get from libpcap/WinPcap is properly aligned.
- *
- * This assumes that, for all compilers that support __attribute__:
- *
- * 1) they support __attribute__((packed));
- *
- * 2) for all instruction set architectures requiring strict
- * alignment, declaring a structure with that attribute
- * causes the compiler to generate code that handles
- * misaligned 2-byte, 4-byte, and 8-byte integral
- * quantities.
- *
- * It does not (yet) handle compilers where you can get the compiler
- * to generate code of that sort by some other means.
- *
- * This is required in order to, for example, keep the compiler from
- * generating, for
+ * 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.
*
- * if (bp->bp_htype == 1 && bp->bp_hlen == 6 && bp->bp_op == BOOTPREQUEST) {
+ * Furthermore, some versions of Visual Studio prior to Visual
+ * Studio 2015 had vsnprintf() (but not snprintf()!), but those
+ * versions don't guarantee null termination, either.
*
- * in print-bootp.c, code that loads the first 4-byte word of a
- * "struct bootp", masking out the bp_hops field, and comparing the result
- * against 0x01010600.
- *
- * Note: this also requires that padding be put into the structure,
- * at least for compilers where it's implemented as __attribute__((packed)).
+ * We assume all UN*Xes that have snprintf() and vsnprintf() provide
+ * C99 behavior.
*/
-#if !(defined(_MSC_VER) && defined(UNALIGNED))
-/* MSVC may have its own macro defined with the same name and purpose. */
-#undef UNALIGNED
-#define UNALIGNED __attribute__((packed))
-#endif
+#if defined(_MSC_VER) || defined(__MINGW32__)
+ #if defined(_MSC_VER) && _MSC_VER >= 1900
+ /*
+ * VS 2015 or newer; just use the C runtime's snprintf() and
+ * vsnprintf().
+ */
+ #define nd_snprintf snprintf
+ #define nd_vsnprintf vsnprintf
+ #else /* defined(_MSC_VER) && _MSC_VER >= 1900 */
+ /*
+ * VS prior to 2015, or MingGW; assume we have _snprintf_s() and
+ * _vsnprintf_s(), which guarantee null termination.
+ */
+ #define nd_snprintf(buf, buflen, ...) \
+ _snprintf_s(buf, buflen, _TRUNCATE, __VA_ARGS__)
+ #define nd_vsnprintf(buf, buflen, fmt, ap) \
+ _vsnprintf_s(buf, buflen, _TRUNCATE, fmt, ap)
+ #endif /* defined(_MSC_VER) && _MSC_VER >= 1900 */
+#else /* defined(_MSC_VER) || defined(__MINGW32__) */
+ /*
+ * Some other compiler, which we assume to be a UN*X compiler.
+ * Use the system's snprintf() if we have it, otherwise use
+ * our own implementation
+ */
+ #ifdef HAVE_SNPRINTF
+ #define nd_snprintf snprintf
+ #else /* HAVE_SNPRINTF */
+ int nd_snprintf (char *str, size_t sz, FORMAT_STRING(const char *format), ...)
+ PRINTFLIKE(3, 4);
+ #endif /* HAVE_SNPRINTF */
+
+ #ifdef HAVE_VSNPRINTF
+ #define nd_vsnprintf vsnprintf
+ #else /* HAVE_VSNPRINTF */
+ int nd_vsnprintf (char *str, size_t sz, FORMAT_STRING(const char *format),
+ va_list ap) PRINTFLIKE(3, 0);
+ #endif /* HAVE_VSNPRINTF */
+#endif /* defined(_MSC_VER) || defined(__MINGW32__) */
/*
* fopen() read and write modes for text files and binary files.
* an 80386, so, for example, it avoids the bswap instruction added in
* the 80486.
*
- * (We don't use them on OS X; Apple provides their own, which *doesn't*
- * avoid the bswap instruction, as OS X only supports machines that
+ * (We don't use them on macOS; Apple provides their own, which *doesn't*
+ * avoid the bswap instruction, as macOS only supports machines that
* have it.)
*/
#if defined(__GNUC__) && defined(__i386__) && !defined(__APPLE__) && !defined(__ntohl)
*/
/*
- * Function attributes, for various compilers.
+ * Statement attributes, for various compilers.
+ *
+ * This was introduced sufficiently recently that compilers implementing
+ * it also implement __has_attribute() (for example, GCC 5.0 and later
+ * have __has_attribute(), and the "fallthrough" attribute was introduced
+ * in GCC 7).
+ *
+ * Unfortunately, Clang does this wrong - a statement
+ *
+ * __attribute__ ((fallthrough));
+ *
+ * produces bogus -Wmissing-declaration "declaration does not declare
+ * anything" warnings (dear Clang: that's not a declaration, it's an
+ * empty statement). GCC, however, has no trouble with this.
*/
-#include "funcattrs.h"
-
-#ifndef min
-#define min(a,b) ((a)>(b)?(b):(a))
-#endif
-#ifndef max
-#define max(a,b) ((b)>(a)?(b):(a))
-#endif
-
-#ifdef __ATTRIBUTE___FALLTHROUGH_OK
+#if __has_attribute(fallthrough) && !defined(__clang__)
# define ND_FALL_THROUGH __attribute__ ((fallthrough))
#else
# define ND_FALL_THROUGH
-#endif /* __ATTRIBUTE___FALLTHROUGH_OK */
+#endif /* __has_attribute(fallthrough) */
#endif /* netdissect_stdinc_h */
projects / tcpdump / blobdiff