puzzles: refactor and resync with upstream

This brings puzzles up-to-date with upstream revision
2d333750272c3967cfd5cd3677572cddeaad5932, though certain changes made
by me, including cursor-only Untangle and some compilation fixes
remain. Upstream code has been moved to its separate subdirectory and
future syncs can be done by simply copying over the new sources.

Change-Id: Ia6506ca5f78c3627165ea6791d38db414ace0804

apps/plugins/puzzles/rbmalloc.c

@@ -0,0 +1,93 @@
+/*
+ * malloc.c: safe wrappers around malloc, realloc, free, strdup
+ */
+
+#include <stdlib.h>
+#include <string.h>
+#include "src/puzzles.h"
+
+/*
+ * smalloc should guarantee to return a useful pointer - Halibut
+ * can do nothing except die when it's out of memory anyway.
+ */
+
+int allocs = 0;
+int frees = 0;
+
+bool audiobuf_available =
+#ifndef COMBINED
+    true;
+#else
+    false;
+#endif
+
+static bool grab_audiobuf(void)
+{
+    if(!audiobuf_available)
+        return false;
+
+    if(rb->audio_status())
+        rb->audio_stop();
+
+    size_t sz, junk;
+    void *audiobuf = rb->plugin_get_audio_buffer(&sz);
+    extern char *giant_buffer;
+
+    add_new_area(audiobuf, sz, giant_buffer);
+    audiobuf_available = false;
+    return true;
+}
+
+void *smalloc(size_t size) {
+    void *p;
+    p = malloc(size);
+    LOGF("allocs: %d", ++allocs);
+    if (!p)
+    {
+        if(grab_audiobuf())
+            return smalloc(size);
+        fatal("out of memory");
+    }
+    return p;
+}
+
+/*
+ * sfree should guaranteeably deal gracefully with freeing NULL
+ */
+void sfree(void *p) {
+    if (p) {
+        ++frees;
+        LOGF("frees: %d, total outstanding: %d", frees, allocs - frees);
+        free(p);
+    }
+}
+
+/*
+ * srealloc should guaranteeably be able to realloc NULL
+ */
+void *srealloc(void *p, size_t size) {
+    void *q;
+    if (p) {
+	q = realloc(p, size);
+    } else {
+        LOGF("allocs: %d", ++allocs);
+	q = malloc(size);
+    }
+    if (!q)
+    {
+        if(grab_audiobuf())
+            return srealloc(p, size);
+        fatal("out of memory");
+    }
+    return q;
+}
+
+/*
+ * dupstr is like strdup, but with the never-return-NULL property
+ * of smalloc (and also reliably defined in all environments :-)
+ */
+char *dupstr(const char *s) {
+    char *r = smalloc(1+strlen(s));
+    strcpy(r,s);
+    return r;
+}