+/* Likewise for struct iri definition */
+#include "iri.h"
+
+/* Useful macros used across the code: */
+
+/* The number of elements in an array. For example:
+ static char a[] = "foo"; -- countof(a) == 4 (note terminating \0)
+ int a[5] = {1, 2}; -- countof(a) == 5
+ char *a[] = { -- countof(a) == 3
+ "foo", "bar", "baz"
+ }; */
+#define countof(array) (sizeof (array) / sizeof ((array)[0]))
+
+/* Zero out a value. */
+#define xzero(x) memset (&(x), '\0', sizeof (x))
+
+/* Convert an ASCII hex digit to the corresponding number between 0
+ and 15. H should be a hexadecimal digit that satisfies isxdigit;
+ otherwise, the result is undefined. */
+#define XDIGIT_TO_NUM(h) ((h) < 'A' ? (h) - '0' : c_toupper (h) - 'A' + 10)
+#define X2DIGITS_TO_NUM(h1, h2) ((XDIGIT_TO_NUM (h1) << 4) + XDIGIT_TO_NUM (h2))
+
+/* The reverse of the above: convert a number in the [0, 16) range to
+ the ASCII representation of the corresponding hexadecimal digit.
+ `+ 0' is there so you can't accidentally use it as an lvalue. */
+#define XNUM_TO_DIGIT(x) ("0123456789ABCDEF"[x] + 0)
+#define XNUM_TO_digit(x) ("0123456789abcdef"[x] + 0)
+
+/* Copy the data delimited with BEG and END to alloca-allocated
+ storage, and zero-terminate it. Arguments are evaluated only once,
+ in the order BEG, END, PLACE. */
+#define BOUNDED_TO_ALLOCA(beg, end, place) do { \
+ const char *BTA_beg = (beg); \
+ int BTA_len = (end) - BTA_beg; \
+ char **BTA_dest = &(place); \
+ *BTA_dest = alloca (BTA_len + 1); \
+ memcpy (*BTA_dest, BTA_beg, BTA_len); \
+ (*BTA_dest)[BTA_len] = '\0'; \
+} while (0)
+
+/* Return non-zero if string bounded between BEG and END is equal to
+ STRING_LITERAL. The comparison is case-sensitive. */
+#define BOUNDED_EQUAL(beg, end, string_literal) \
+ ((end) - (beg) == sizeof (string_literal) - 1 \
+ && !memcmp (beg, string_literal, sizeof (string_literal) - 1))
+
+/* The same as above, except the comparison is case-insensitive. */
+#define BOUNDED_EQUAL_NO_CASE(beg, end, string_literal) \
+ ((end) - (beg) == sizeof (string_literal) - 1 \
+ && !strncasecmp (beg, string_literal, sizeof (string_literal) - 1))
+
+/* Like ptr=strdup(str), but allocates the space for PTR on the stack.
+ This cannot be an expression because this is not portable:
+ #define STRDUP_ALLOCA(str) (strcpy (alloca (strlen (str) + 1), str))
+ The problem is that some compilers can't handle alloca() being an
+ argument to a function. */
+
+#define STRDUP_ALLOCA(ptr, str) do { \
+ char **SA_dest = &(ptr); \
+ const char *SA_src = (str); \
+ *SA_dest = (char *)alloca (strlen (SA_src) + 1); \
+ strcpy (*SA_dest, SA_src); \
+} while (0)