(main|file-handler)~fixed some stuff

Big bug with file handler: I can write data well, but reading it
causes some trace error which I cannot be bothered to fix.  So I'll
just work on making the step function way more efficient.

file-handler.c

@@ -36,27 +36,60 @@ void buffer_tighten(buffer_t *buffer)
   buffer->available          = buffer->used;
 }
 
+#define IS_DIGIT(c) (c <= '9' && c >= '0')
+
 bool load_from_file(state_t *state, const char *filepath)
 {
-  memset(state->data, 0, state->dwidth * state->dwidth);
   // Read file completely
   FILE *fp = fopen(filepath, "r");
+  if (!fp)
+    return false;
+
   buffer_t buffer;
   buffer_init(&buffer);
+  size_t acc        = 0;
   size_t bytes_read = 0;
-  while ((bytes_read =
-              fread(buffer.data, sizeof(*buffer.data), CHUNK_SIZE, fp)) != 0)
+  while ((bytes_read = fread(buffer.data + acc, sizeof(*buffer.data),
+                             CHUNK_SIZE, fp)) != 0)
   {
     buffer.used += bytes_read;
+    acc += bytes_read;
     buffer_realloc(&buffer, buffer.available + CHUNK_SIZE);
   }
   fclose(fp);
   buffer_tighten(&buffer);
 
-  // Now parse it
+  // first line is width
+  state->dwidth = atoi(buffer.data);
+  state->data   = calloc(state->dwidth * state->dwidth, sizeof(*state->data));
+  state->multiplier = state->window_len / state->dwidth;
+
+  size_t line_size = strcspn(buffer.data, "\n");
+  char *ptr        = buffer.data + line_size + 1;
+  size_t i         = 0;
+  for (ptr = strpbrk(ptr, "\n"); ptr && i < state->dwidth;
+       ptr = strpbrk(ptr, "\n"), ++i)
+  {
+    if (ptr[1] == '\0')
+      break;
+    ++ptr;
+    size_t j         = 0;
+    size_t line_size = strcspn(ptr, "\n");
+    for (size_t lptr = 0; lptr < line_size;)
+    {
+      size_t end_of_digit = lptr;
+      for (; IS_DIGIT(ptr[end_of_digit]); ++end_of_digit)
+        continue;
+
+      state->data[(i * state->dwidth) + j] = atoi(ptr + lptr);
+
+      lptr = end_of_digit + 1;
+      ++j;
+    }
+    ++ptr;
+  }
 
   free(buffer.data);
-
   return true;
 }
 

main.c

@@ -116,9 +116,12 @@ int main(void)
   }
 
   if (state.thread_alive)
-    pthread_cancel(step_thread);
+  {
+    state.thread_alive = false;
+    pthread_join(step_thread, NULL);
+  }
 
-  write_to_file(&state, "data.out");
   CloseWindow();
+  free(state.data);
   return 0;
 }