NASM 0.91nasm-0.91

1 files changed, 84 insertions, 0 deletions

diff --git a/sync.c b/sync.c
new file mode 100644
index 00000000..77212d8c
--- /dev/null
+++ b/sync.c
@@ -0,0 +1,84 @@
+/* sync.c   the Netwide Disassembler synchronisation processing module
+ *
+ * The Netwide Assembler is copyright (C) 1996 Simon Tatham and
+ * Julian Hall. All rights reserved. The software is
+ * redistributable under the licence given in the file "Licence"
+ * distributed in the NASM archive.
+ */
+
+#include <stdio.h>
+#include <limits.h>
+
+#include "sync.h"
+
+#define SYNC_MAX 4096		       /* max # of sync points */
+
+static struct Sync {
+    unsigned long pos;
+    unsigned long length;
+} synx[SYNC_MAX];
+static int nsynx;
+
+void init_sync(void) {
+    nsynx = 0;
+}
+
+void add_sync(unsigned long pos, unsigned long length) {
+    int i;
+
+    if (nsynx == SYNC_MAX)
+	return;			       /* can't do anything - overflow */
+
+    nsynx++;
+    synx[nsynx].pos = pos;
+    synx[nsynx].length = length;
+
+    for (i = nsynx; i > 1; i /= 2) {
+	if (synx[i/2].pos > synx[i].pos) {
+	    struct Sync t;
+	    t = synx[i/2];	       /* structure copy */
+	    synx[i/2] = synx[i];       /* structure copy again */
+	    synx[i] = t;	       /* another structure copy */
+	}
+    }
+}
+
+unsigned long next_sync(unsigned long position, unsigned long *length) {
+    while (nsynx > 0 && synx[1].pos + synx[1].length <= position) {
+	int i, j;
+	struct Sync t;
+	t = synx[nsynx];	       /* structure copy */
+	synx[nsynx] = synx[1];	       /* structure copy */
+	synx[1] = t;		       /* ditto */
+
+	nsynx--;
+
+        i = 1;
+	while (i*2 <= nsynx) {
+	    j = i*2;
+	    if (synx[j].pos < synx[i].pos &&
+		(j+1 > nsynx || synx[j+1].pos > synx[j].pos)) {
+		t = synx[j];	       /* structure copy */
+		synx[j] = synx[i];     /* lots of these... */
+		synx[i] = t;	       /* ...aren't there? */
+		i = j;
+	    } else if (j+1 <= nsynx && synx[j+1].pos < synx[i].pos) {
+		t = synx[j+1];	       /* structure copy */
+		synx[j+1] = synx[i];   /* structure <yawn> copy */
+		synx[i] = t;	       /* structure copy <zzzz....> */
+		i = j+1;
+	    } else
+		break;
+	}
+    }
+
+    if (nsynx > 0) {
+	if (length)
+	    *length = synx[1].length;
+	return synx[1].pos;
+    } else {
+	if (length)
+	    *length = 0L;
+	return ULONG_MAX;
+    }
+}