wip

1 files changed, 30 insertions, 7 deletions

diff --git a/test/threads.cxx b/test/threads.cxx
index 4c8a94d11..466953b37 100644
--- a/test/threads.cxx
+++ b/test/threads.cxx
@@ -25,7 +25,7 @@
 #  include "threads.h"
 #  include <stdio.h>
 #  include <math.h>
-#  include <vector>
+#  include <stdlib.h>
 
 // min. time in seconds before calling Fl::awake(...)
 #define DELTA 0.25
@@ -39,9 +39,30 @@ struct prime {
   Fl_Terminal *terminal;                // widget to write output to
   unsigned long max_prime;              // highest prime found so far
   Fl_Output *value;                     // highest prime output widget
-  std::vector<unsigned long> primes;    // collected primes within time frame
+  unsigned long *primes;                // collected primes within time frame
+  size_t primes_count;                  // number of collected primes
+  size_t primes_alloc;                  // allocated size
 };
 
+static void primes_init(struct prime *pr) {
+  pr->primes = 0;
+  pr->primes_count = 0;
+  pr->primes_alloc = 0;
+}
+
+static void primes_push(struct prime *pr, unsigned long n) {
+  if (pr->primes_count >= pr->primes_alloc) {
+    size_t new_alloc = pr->primes_alloc ? pr->primes_alloc * 2 : 64;
+    pr->primes = (unsigned long *)realloc(pr->primes, new_alloc * sizeof(unsigned long));
+    pr->primes_alloc = new_alloc;
+  }
+  pr->primes[pr->primes_count++] = n;
+}
+
+static void primes_clear(struct prime *pr) {
+  pr->primes_count = 0;
+}
+
 Fl_Thread prime_thread;
 
 Fl_Terminal *tty1, *tty2;
@@ -61,7 +82,9 @@ void magic_number_cb(void *p) {
 void update_handler(void *v) {
   char max_buf[32];
   struct prime *pr = (struct prime *)v;
-  for (auto n : pr->primes) {
+  size_t i;
+  for (i = 0; i < pr->primes_count; i++) {
+    unsigned long n = pr->primes[i];
     pr->terminal->printf("prime: %10lu\n", n);
     if (n > pr->max_prime)
       pr->max_prime = n;
@@ -103,8 +126,8 @@ extern "C" void* prime_func(void* p) {
   pr[0].terminal  = pr[1].terminal  = terminal;
   pr[0].max_prime = pr[1].max_prime = 0;
   pr[0].value     = pr[1].value     = value;
-  pr[0].primes.clear();
-  pr[1].primes.clear();
+  primes_init(&pr[0]);
+  primes_init(&pr[1]);
   int pi = 0;   // prime buffer index
 
   Fl_Timestamp last = Fl::now();
@@ -129,7 +152,7 @@ extern "C" void* prime_func(void* p) {
 
     if (pp > hn) { // n is a prime
 
-      pr[pi].primes.push_back(n);
+      primes_push(&pr[pi], n);
 
       // Send a message to the main thread, at which point it will
       // process any pending updates.
@@ -140,7 +163,7 @@ extern "C" void* prime_func(void* p) {
         last = Fl::now();
         Fl::awake(update_handler, (void *)(&pr[pi]));
         pi = 1 - pi;                            // switch to alternate buffer
-        pr[pi].primes.clear();                  // clear primes
+        primes_clear(&pr[pi]);                  // clear primes
       }
 
       if (n > max_value) {