1 files changed, 215 insertions, 0 deletions
diff --git a/extension/intdiv.c b/extension/intdiv.c
new file mode 100644
index 00000000..77b4290b
--- /dev/null
+++ b/extension/intdiv.c
@@ -0,0 +1,215 @@
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include <stdio.h>
+#include <assert.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <math.h>
+
+#include <sys/types.h>
+#include <sys/stat.h>
+
+#include "gawkapi.h"
+
+#ifdef HAVE_MPFR
+#include <gmp.h>
+#include <mpfr.h>
+#endif
+
+#include "gettext.h"
+#define _(msgid)  gettext(msgid)
+#define N_(msgid) msgid
+
+static const gawk_api_t *api;	/* for convenience macros to work */
+static awk_ext_id_t *ext_id;
+static const char *ext_version = "intdiv extension: version 1.0";
+
+int plugin_is_GPL_compatible;
+
+/* double_to_int --- get the integer part of a double */
+
+static double
+double_to_int(double d)
+{
+	if (d >= 0)
+		d = floor(d);
+	else
+		d = ceil(d);
+	return d;
+}
+
+/* array_set_number --- set an array element to a numeric value */
+
+static void
+array_set_number(awk_array_t array, const char *sub, size_t sublen, double num)
+{
+	awk_value_t index, tmp;
+
+	set_array_element(array, make_const_string(sub, sublen, & index), make_number(num, & tmp));
+}
+
+#ifdef HAVE_MPFR
+
+/* mpz_conv --- convert an awk_value_t to an MPZ value */
+
+static mpz_ptr
+mpz_conv(const awk_value_t *arg, mpz_ptr tmp)
+{
+	switch (arg->num_type) {
+	case AWK_NUMBER_TYPE_MPZ:
+		return arg->num_ptr;
+	case AWK_NUMBER_TYPE_MPFR:
+		if (! mpfr_number_p(arg->num_ptr))
+			return NULL;
+		mpz_init(tmp);
+		mpfr_get_z(tmp, arg->num_ptr, MPFR_RNDZ);
+		return tmp;
+	case AWK_NUMBER_TYPE_DOUBLE:	/* can this happen? */
+		mpz_init(tmp);
+		mpz_set_d(tmp, double_to_int(arg->num_value));
+		return tmp;
+	default:	/* should never happen */
+		fatal(ext_id, _("intdiv: invalid numeric type `%d'"), arg->num_type);
+		return NULL;
+	}
+}
+
+/* array_set_mpz --- set an array element to an MPZ value */
+
+static void
+array_set_mpz(awk_array_t array, const char *sub, size_t sublen, mpz_ptr num)
+{
+	awk_value_t index, tmp;
+
+	set_array_element(array, make_const_string(sub, sublen, & index), make_number_mpz(num, & tmp));
+}
+
+#endif
+
+/* do_intdiv --- do integer division, return quotient and remainder in dest array */
+
+/*
+ * We define the semantics as:
+ * 	numerator = int(numerator)
+ *	denominator = int(denonmator)
+ *	quotient = int(numerator / denomator)
+ *	remainder = int(numerator % denomator)
+ */
+
+static awk_value_t *
+do_intdiv(int nargs, awk_value_t *result, struct awk_ext_func *unused)
+{
+	awk_value_t nv, dv, array_param;
+	awk_array_t array;
+
+	if (! get_argument(0, AWK_NUMBER, & nv)) {
+		warning(ext_id, _("intdiv: first argument must be numeric"));
+		return make_number(-1, result);
+	}
+	if (! get_argument(1, AWK_NUMBER, & dv)) {
+		warning(ext_id, _("intdiv: second argument must be numeric"));
+		return make_number(-1, result);
+	}
+	if (! get_argument(2, AWK_ARRAY, & array_param)) {
+		warning(ext_id, _("intdiv: third argument must be an array"));
+		return make_number(-1, result);
+	}
+	array = array_param.array_cookie;
+	clear_array(array);
+
+#ifdef HAVE_MPFR
+	if (nv.num_type == AWK_NUMBER_TYPE_DOUBLE && dv.num_type == AWK_NUMBER_TYPE_DOUBLE) {
+#endif
+		/* regular precision */
+		double num, denom, quotient, remainder;
+
+		num = double_to_int(nv.num_value);
+		denom = double_to_int(dv.num_value);
+
+		if (denom == 0.0) {
+			warning(ext_id, _("intdiv: division by zero attempted"));
+			return make_number(-1, result);
+		}
+
+		quotient = double_to_int(num / denom);
+#ifdef HAVE_FMOD
+		remainder = fmod(num, denom);
+#else	/* ! HAVE_FMOD */
+		(void) modf(num / denom, & remainder);
+		remainder = num - remainder * denom;
+#endif	/* ! HAVE_FMOD */
+		remainder = double_to_int(remainder);
+
+		array_set_number(array, "quotient", 8, quotient);
+		array_set_number(array, "remainder", 9, remainder);
+#ifdef HAVE_MPFR
+	} else {
+		/* extended precision */
+		mpz_ptr numer, denom;
+		mpz_t numer_tmp, denom_tmp;
+		mpz_ptr quotient, remainder;
+
+		/* convert numerator and denominator to integer */
+		if (!(numer = mpz_conv(&nv, numer_tmp))) {
+			warning(ext_id, _("intdiv: numerator is not finite"));
+			return make_number(-1, result);
+		}
+		if (!(denom = mpz_conv(&dv, denom_tmp))) {
+			warning(ext_id, _("intdiv: denominator is not finite"));
+			if (numer == numer_tmp)
+				mpz_clear(numer);
+			return make_number(-1, result);
+		}
+		if (mpz_sgn(denom) == 0) {
+			warning(ext_id, _("intdiv: division by zero attempted"));
+			if (numer == numer_tmp)
+				mpz_clear(numer);
+			if (denom == denom_tmp)
+				mpz_clear(denom);
+			return make_number(-1, result);
+		}
+
+		/* ask gawk to allocate return values for us */
+		quotient = get_mpz_ptr();
+		remainder = get_mpz_ptr();
+
+		/* do the division */
+		mpz_tdiv_qr(quotient, remainder, numer, denom);
+
+		array_set_mpz(array, "quotient", 8, quotient);
+		array_set_mpz(array, "remainder", 9, remainder);
+
+		/* release temporary variables */
+		if (numer == numer_tmp)
+			mpz_clear(numer);
+		if (denom == denom_tmp)
+			mpz_clear(denom);
+	}
+#endif
+
+	return make_number(0, result);
+}
+
+static awk_ext_func_t func_table[] = {
+	{ "intdiv", do_intdiv, 3, 3, awk_false, NULL },
+};
+
+/* init_intdiv --- initialization routine */
+
+static awk_bool_t
+init_intdiv(void)
+{
+#ifdef HAVE_MPFR
+	check_mpfr_version(intdiv)
+#endif
+	return awk_true;
+}
+
+static awk_bool_t (*init_func)(void) = init_intdiv;
+
+/* define the dl_load function using the boilerplate macro */
+
+dl_load_func(func_table, intdiv, "")