+
+/**
+ * Return a random non-negative integer in an interval.
+ *
+ * \param max Determines maximal possible return value.
+ *
+ * \return An integer between zero and \p max - 1, inclusively.
+ */
+_static_inline_ long int para_random(unsigned max)
+{
+ return ((max + 0.0) * (random() / (RAND_MAX + 1.0)));
+}
+
+/** Round up x to next multiple of y. */
+#define ROUND_UP(x, y) ({ \
+ const typeof(y) _divisor = y; \
+ ((x) + _divisor - 1) / _divisor * _divisor; })
+
+/** Round down x to multiple of y. */
+#define ROUND_DOWN(x, y) ({ \
+ const typeof(y) _divisor = y; \
+ (x) / _divisor * _divisor; })
+
+/** Divide and round up to next integer. */
+#define DIV_ROUND_UP(x, y) ({ \
+ typeof(y) _divisor = y; \
+ ((x) + _divisor - 1) / _divisor; })
+
+/**
+ * Assert a build-time dependency, as an expression.
+ *
+ * \param cond The compile-time condition which must be true.
+ *
+ * Compilation will fail if the condition isn't true, or can't be evaluated by
+ * the compiler. This can be used in an expression: its value is "0".
+ *
+ * Taken from ccan.
+ */
+#define EXPR_BUILD_ASSERT(cond) (sizeof(char [1 - 2 * !(cond)]) - 1)
+
+/* &a[0] degrades to a pointer: a different type from an array */
+#define _array_size_chk(arr) EXPR_BUILD_ASSERT(\
+ !__builtin_types_compatible_p(typeof(arr), typeof(&(arr)[0])))
+/** Get the size of an array */
+#define ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0]) + _array_size_chk(arr))
+
+/**
+ * Wrapper for isspace.
+ * NetBSD needs this.
+ */
+/*
+ * The values should be cast to an unsigned char first, then to int.
+ * Why? Because the isdigit (as do all other is/to functions/macros)
+ * expect a number from 0 upto and including 255 as their (int) argument.
+ * Because char is signed on most systems, casting it to int immediately
+ * gives the functions an argument between -128 and 127 (inclusive),
+ * which they will use as an array index, and which will thus fail
+ * horribly for characters which have their most significant bit set.
+ */
+#define para_isspace(c) isspace((int)(unsigned char)(c))
+
+/** Data that indicates an eof-condition for a fec-encoded stream. */
+#define FEC_EOF_PACKET "\xec\x0d\xcc\xfe\0\0\0\0" \
+ "\0\0\0\0\0\0\0\0" "\0\0\0\0\0\0\0\0" "\0\0\0\0\0\0\0\0"
+#define FEC_EOF_PACKET_LEN 32
+
+/** Used to avoid a shortcoming in vim's syntax highlighting. */
+#define EMBRACE(...) { __VA_ARGS__}
+
+/** A nice cup of STFU for Mr gcc. */
+#define do_nothing do {/* nothing */} while (0)
+
+/**
+ * The sample formats supported by paraslash.
+ *
+ * It may be determined by one of the following sources:
+ *
+ * 1. The decoding filter (para_audiod only). In this case, it is always
+ * \p SF_S16_LE which is the canonical format used within decoders.
+ *
+ * 2. The wav header (para_write only).
+ *
+ * 3. The --format option of para_write.
+ */
+#define SAMPLE_FORMATS \
+ SAMPLE_FORMAT(SF_S8, "8 bit signed"), \
+ SAMPLE_FORMAT(SF_U8, "8 bit unsigned"), \
+ SAMPLE_FORMAT(SF_S16_LE, "16 bit signed, little endian"), \
+ SAMPLE_FORMAT(SF_S16_BE, "16 bit signed, big endian"), \
+ SAMPLE_FORMAT(SF_U16_LE, "16 bit unsigned, little endian"), \
+ SAMPLE_FORMAT(SF_U16_BE, "16 bit unsigned, big endian"), \
+
+#define SAMPLE_FORMAT(a, b) a
+enum sample_format {SAMPLE_FORMATS};
+#undef SAMPLE_FORMAT
+#define SAMPLE_FORMAT(a, b) b
+
+/** Debug loglevel, gets really noisy. */
+#define LL_DEBUG 0
+/** Still noisy, but won't fill your disk. */
+#define LL_INFO 1
+/** Normal, but significant event. */
+#define LL_NOTICE 2
+/** Unexpected event that can be handled. */
+#define LL_WARNING 3
+/** Unhandled error condition. */
+#define LL_ERROR 4
+/** System might be unreliable. */
+#define LL_CRIT 5
+/** Last message before exit. */
+#define LL_EMERG 6
+/** Number of all loglevels. */
+#define NUM_LOGLEVELS 7
+
+/** Log messages with lower priority than that will not be compiled in. */
+#define COMPILE_TIME_LOGLEVEL 0
+
+/** \cond */
+#if LL_DEBUG >= COMPILE_TIME_LOGLEVEL
+#define PARA_DEBUG_LOG(f,...) para_log(LL_DEBUG, "%s: " f, __FUNCTION__, ## __VA_ARGS__)
+#else
+#define PARA_DEBUG_LOG(...) do {;} while (0)
+#endif
+
+#if LL_INFO >= COMPILE_TIME_LOGLEVEL
+#define PARA_INFO_LOG(f,...) para_log(LL_INFO, "%s: " f, __FUNCTION__, ## __VA_ARGS__)
+#else
+#define PARA_INFO_LOG(...) do {;} while (0)
+#endif
+
+#if LL_NOTICE >= COMPILE_TIME_LOGLEVEL
+#define PARA_NOTICE_LOG(f,...) para_log(LL_NOTICE, "%s: " f, __FUNCTION__, ## __VA_ARGS__)
+#else
+#define PARA_NOTICE_LOG(...) do {;} while (0)
+#endif
+
+#if LL_WARNING >= COMPILE_TIME_LOGLEVEL
+#define PARA_WARNING_LOG(f,...) para_log(LL_WARNING, "%s: " f, __FUNCTION__, ## __VA_ARGS__)
+#else
+#define PARA_WARNING_LOG(...) do {;} while (0)
+#endif
+
+#if LL_ERROR >= COMPILE_TIME_LOGLEVEL
+#define PARA_ERROR_LOG(f,...) para_log(LL_ERROR, "%s: " f, __FUNCTION__, ## __VA_ARGS__)
+#else
+#define PARA_ERROR_LOG(...) do {;} while (0)
+#endif
+
+#if LL_CRIT >= COMPILE_TIME_LOGLEVEL
+#define PARA_CRIT_LOG(f,...) para_log(LL_CRIT, "%s: " f, __FUNCTION__, ## __VA_ARGS__)
+#else
+#define PARA_CRIT_LOG(...) do {;} while (0)
+#endif
+
+#if LL_EMERG >= COMPILE_TIME_LOGLEVEL
+#define PARA_EMERG_LOG(f,...) para_log(LL_EMERG, "%s: " f, __FUNCTION__, ## __VA_ARGS__)
+#else
+#define PARA_EMERG_LOG(...)
+#endif
+/** \endcond */