* arith.c (INT_PTR_MAX_MP): New static variable.

(in_int_ptr_range): New function.
(arith_init): Initialize INT_PTR_MAX_MP.

* arith.h (in_int_ptr_range): Declared.

* lib.c (c_num): Allow bignums to be converted to a cnum, if
they are in range, rather than allowing only fixnums.

* rand.c (make_random_state): Now that we have such a function,
initialize random seed using time value from time_sec_usec rather than
from time and clock.  clock is bad for random seeding because it
measures virtual time since the start of the process.

5 files changed, 38 insertions, 6 deletions

diff --git a/ChangeLog b/ChangeLog
index 69a0ca4f..838e5dbc 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,21 @@
 2012-04-10  Kaz Kylheku  <kaz@kylheku.com>
 
+	* arith.c (INT_PTR_MAX_MP): New static variable.
+	(in_int_ptr_range): New function.
+	(arith_init): Initialize INT_PTR_MAX_MP.
+
+	* arith.h (in_int_ptr_range): Declared.
+
+	* lib.c (c_num): Allow bignums to be converted to a cnum, if
+	they are in range, rather than allowing only fixnums.
+
+	* rand.c (make_random_state): Now that we have such a function,
+	initialize random seed using time value from time_sec_usec rather than
+	from time and clock.  clock is bad for random seeding because it
+	measures virtual time since the start of the process.
+
+2012-04-10  Kaz Kylheku  <kaz@kylheku.com>
+
 	* configure: Switch from _POSIX_C_SOURCE=2 to _XOPEN_SOURCE.
 	We will be relying on the gettimeofday function which only came
 	into POSIX in 2001, but was in Unix long before then.
diff --git a/arith.c b/arith.c
index de8d782e..1d784a6e 100644
--- a/arith.c
+++ b/arith.c
@@ -51,7 +51,7 @@
 #define CNUM_BIT ((int) sizeof (cnum) * CHAR_BIT)
 #define ABS(A) ((A) < 0 ? -(A) : (A))
 
-static mp_int NUM_MAX_MP;
+static mp_int NUM_MAX_MP, INT_PTR_MAX_MP;
 
 val make_bignum(void)
 {
@@ -90,6 +90,11 @@ val normalize(val bignum)
   }
 }
 
+val in_int_ptr_range(val bignum)
+{
+  return (mp_cmp_mag(mp(bignum), &INT_PTR_MAX_MP) == MP_GT) ? nil : t;
+}
+
 int highest_bit(int_ptr_t n)
 {
 #if SIZEOF_PTR == 8
@@ -1487,4 +1492,6 @@ void arith_init(void)
 {
   mp_init(&NUM_MAX_MP);
   mp_set_intptr(&NUM_MAX_MP, NUM_MAX);
+  mp_init(&INT_PTR_MAX_MP);
+  mp_set_intptr(&INT_PTR_MAX_MP, INT_PTR_MAX);
 }
diff --git a/arith.h b/arith.h
index 91e197e0..52aad603 100644
--- a/arith.h
+++ b/arith.h
@@ -28,4 +28,5 @@ val make_bignum(void);
 val bignum(cnum cn);
 int highest_bit(int_ptr_t n);
 val normalize(val bignum);
+val in_int_ptr_range(val bignum);
 void arith_init(void);
diff --git a/lib.c b/lib.c
index f858df16..e0c73dbb 100644
--- a/lib.c
+++ b/lib.c
@@ -1151,11 +1151,18 @@ val num(cnum n)
 
 cnum c_num(val num)
 {
-  switch (tag(num)) {
-  case TAG_CHR: case TAG_NUM:
+  switch (type(num)) {
+  case CHR: case NUM:
     return ((cnum) num) >> TAG_SHIFT;
+  case BGNUM:
+    if (in_int_ptr_range(num)) {
+      int_ptr_t out;
+      mp_get_intptr(mp(num), &out);
+      return out;
+    }
+    uw_throwf(error_s, lit("c_num: ~s is out of cnum range"), num, nao);
   default:
-    type_mismatch(lit("~s is not a fixnum"), num, nao);
+    type_mismatch(lit("c_num: ~s is not an integer"), num, nao);
   }
 }
 
diff --git a/rand.c b/rand.c
index 30708ab7..4bb3995a 100644
--- a/rand.c
+++ b/rand.c
@@ -136,8 +136,9 @@ val make_random_state(val seed)
     r->state[3] = (s >> 96) & 0xFFFFFFFFul;
 #endif
   } else if (nullp(seed)) {
-    r->state[0] = (rand32_t) time(0);
-    r->state[1] = (rand32_t) clock();
+    val time = time_sec_usec();
+    r->state[0] = (rand32_t) c_num(car(time));
+    r->state[1] = (rand32_t) c_num(cdr(time));
     memset(r->state + 2, 0xAA, sizeof r->state - 2 * sizeof r->state[0]);
   } else if (random_state_p(seed)) {
     struct random_state *rseed = (struct random_state *)