Added missing libsw library

external/libsdf/libsw/heap.c

@@ -0,0 +1,87 @@
+/* Super-fast priority queue. ?  Completely inlined by gcc. */
+/* Assume that each pointer points at */
+/* a key, AND whatever else the caller is interested in keeping. */
+
+#ifndef assert
+#include "Assert.h"
+#endif
+#include <stddef.h>
+#include <float.h>
+#include "Malloc.h"
+#define HEAPdotC
+#include "heap.h"
+
+#if !defined(HeapKey) || !defined(HeapLeft)
+ # error Heap macros undefined
+#endif
+
+/* These save us from an extra comparison inside our loops */
+const float HeapMinf = -FLT_MAX;
+const float HeapInf = FLT_MAX;
+
+/* I wonder if some const decls would be correct? */
+void HeapInit(Heap *hp, unsigned int sz){
+    assert(sz > 0);
+    hp->arr = Malloc( (sz+1)*sizeof(*(hp->arr)) );
+    assert(hp->arr);
+    hp->sz = sz;
+    hp->cnt = 1;
+    hp->arr[0] = &HeapInf;
+}
+ 
+void HeapTerminate(Heap *hp){
+    Free((void *)hp->arr);
+    hp->arr = NULL;
+    hp->sz = hp->cnt = 0;
+}
+
+int HeapIsBad(const Heap *hp){
+    unsigned int i, ri, li;
+    const float **arr = hp->arr;
+
+    for( i=1, li=2, ri=3;
+	li < hp->cnt;
+	i++, li = HeapLeft(i), ri = li+1){
+	if( HeapKey(i) < HeapKey(li) )
+	    return li;
+	if( ri < hp->cnt && HeapKey(i) < HeapKey(ri) )
+	    return ri;
+    }
+    return 0;
+}
+
+#ifdef STANDALONE
+#include <stdio.h>
+
+float data[] = {5., 1., 3., 2., 7., 3., 4.};
+
+void HeapPrint(Heap *hp){
+    unsigned int i;
+    for(i=1; i<hp->cnt; i++){
+	printf("%d %g\n", i, *(hp->arr[i]));
+    }
+}
+
+int main(int argc, char **argv){
+    Heap H;
+    float *top;
+    unsigned int i;
+    unsigned int ndata;
+
+    HeapInit(&H, 2);
+    ndata = sizeof(data)/sizeof(*data);
+    for(i=0; i<ndata; i++){
+	HeapPush(&H, &data[i]);
+	printf("Inserted %g\n", data[i]);
+	HeapPrint(&H);
+    }
+
+    for(i=0; i<ndata; i++){
+	HeapPop(&H, &top);
+	printf("popped %g\n", *top);
+	HeapPrint(&H);
+    }
+    return EXIT_SUCCESS;
+}
+#endif
+/* Undefine our private macros because this file might be #include'ed */