1 files changed, 87 insertions, 0 deletions
diff --git a/moon-abe/pbc-0.5.14/arith/random.c b/moon-abe/pbc-0.5.14/arith/random.c
new file mode 100644
index 00000000..68228b3f
--- /dev/null
+++ b/moon-abe/pbc-0.5.14/arith/random.c
@@ -0,0 +1,87 @@
+#include <stdio.h>
+#include <stdint.h> // for intptr_t
+#include <stdlib.h>
+#include <gmp.h>
+#include "pbc_random.h"
+#include "pbc_utils.h"
+#include "pbc_memory.h"
+
+void pbc_init_random(void);
+
+// Must use pointer due to lack of gmp_randstate_ptr.
+static gmp_randstate_t *get_rs(void) {
+  static int rs_is_ready;
+  static gmp_randstate_t rs;
+  if (!rs_is_ready) {
+    gmp_randinit_default(rs);
+    rs_is_ready = 1;
+  }
+  return &rs;
+}
+
+static void deterministic_mpz_random(mpz_t z, mpz_t limit, void *data) {
+  UNUSED_VAR (data);
+  mpz_urandomm(z, *get_rs(), limit);
+}
+
+static void file_mpz_random(mpz_t r, mpz_t limit, void *data) {
+  char *filename = (char *) data;
+  FILE *fp;
+  int n, bytecount, leftover;
+  unsigned char *bytes;
+  mpz_t z;
+  mpz_init(z);
+  fp = fopen(filename, "rb");
+  if (!fp) return;
+  n = mpz_sizeinbase(limit, 2);
+  bytecount = (n + 7) / 8;
+  leftover = n % 8;
+  bytes = (unsigned char *) pbc_malloc(bytecount);
+  for (;;) {
+    if (!fread(bytes, 1, bytecount, fp)) {
+      pbc_warn("error reading source of random bits");
+      return;
+    }
+    if (leftover) {
+      *bytes = *bytes % (1 << leftover);
+    }
+    mpz_import(z, bytecount, 1, 1, 0, 0, bytes);
+    if (mpz_cmp(z, limit) < 0) break;
+  }
+  fclose(fp);
+  mpz_set(r, z);
+  mpz_clear(z);
+  pbc_free(bytes);
+}
+
+static void (*current_mpz_random)(mpz_t, mpz_t, void *);
+static void *current_random_data;
+static int random_function_ready = 0;
+
+void pbc_random_set_function(void (*fun)(mpz_t, mpz_t, void *), void *data) {
+  current_mpz_random = fun;
+  current_random_data = data;
+  random_function_ready = 1;
+}
+
+void pbc_mpz_random(mpz_t z, mpz_t limit) {
+  if (!random_function_ready) pbc_init_random();
+  current_mpz_random(z, limit, current_random_data);
+}
+
+void pbc_mpz_randomb(mpz_t z, unsigned int bits) {
+  mpz_t limit;
+  mpz_init(limit);
+  mpz_setbit(limit, bits);
+  pbc_mpz_random(z, limit);
+  mpz_clear(limit);
+}
+
+void pbc_random_set_deterministic(unsigned int seed) {
+  gmp_randseed_ui(*get_rs(), seed);
+  pbc_random_set_function(deterministic_mpz_random, NULL);
+}
+
+void pbc_random_set_file(char *filename) {
+  pbc_random_set_function(file_mpz_random, filename);
+}