From 116ba8fb912719a93258eee56b4dad2e31757ca2 Mon Sep 17 00:00:00 2001
From: david <david@e0a8ed71-7df4-0310-8962-fdc924857419>
Date: Fri, 15 Aug 2008 05:59:05 +0000
Subject: [PATCH] Change the completion percentage algorithm to estimate the
 total number of probes that will be sent and calculate from that. This makes
 the 100% completion match up closely with the end of the scan, as the
 estimate gets better as the scan gets closer to finishing. It also works
 against filtered hosts. There is still the related problem that the
 completion time estimate uses a global average to estimate completion rate,
 so it tends to underestimate.

---
 scan_engine.cc | 30 +++++++++++++++++-------------
 1 file changed, 17 insertions(+), 13 deletions(-)

diff --git a/scan_engine.cc b/scan_engine.cc
index 16c24ebd4..85ae63c11 100644
--- a/scan_engine.cc
+++ b/scan_engine.cc
@@ -1359,24 +1359,28 @@ HostScanStats *UltraScanInfo::nextIncompleteHost() {
    is done. */
 double UltraScanInfo::getCompletionFraction() {
   list<HostScanStats *>::iterator hostI;
-  HostScanStats *host;
-  int maxtries;
-  double thishostpercdone;
   double total;
   
   /* Add 1 for each completed host. */
   total= gstats->numtargets - numIncompleteHosts();
-  /* For incomplete hosts add the fraction of finished to total ports. */
+  /* Get the completion fraction for each incomplete host. */
   for(hostI = incompleteHosts.begin(); hostI != incompleteHosts.end(); hostI++) {
-    host = *hostI;
-    maxtries = host->allowedTryno(NULL, NULL) + 1;
-    // This is inexact (maxtries - 1) because numprobes_sent includes
-    // at least one try of ports_finished.
-    thishostpercdone = host->ports_finished * (maxtries - 1) + host->numprobes_sent;
-    thishostpercdone /= maxtries * gstats->numprobes;
-    if (thishostpercdone >= 0.9999)
-      thishostpercdone = 0.9999;
-    total += thishostpercdone;
+    HostScanStats *host = *hostI;
+    int ports_left;
+    double rate;
+    double probes_left;
+
+    ports_left = host->freshPortsLeft();
+    if (ports_left == gstats->numprobes)
+      continue;
+    /* Get the overall rate of probes sent to ports completed. */
+    rate = (double) host->numprobes_sent / (gstats->numprobes - ports_left);
+    /* Find out how many probes it will take to scan the remainder of the ports
+       at that rate. */
+    probes_left = rate * host->freshPortsLeft();
+    /* Get the completion fraction: number of probes sent divided by estimated
+       total number of probes. */
+    total += (double) host->numprobes_sent / (host->numprobes_sent + probes_left);
   }
 
   return total / gstats->numtargets;