Rework SPA fix to avoid overflows. Bug 2571

[users/jgh/exim.git] / src / exim_monitor / em_queue.c

diff --git a/src/exim_monitor/em_queue.c b/src/exim_monitor/em_queue.c
index d4c01a628c70dcd75c5f93e3be95cfc641a863c6..2146fcb8ce420c66b87fd1e064e3bedeca8dd46c 100644 (file)
--- a/src/exim_monitor/em_queue.c
+++ b/src/exim_monitor/em_queue.c
@@ -3,6 +3,7 @@
 *************************************************/
 
 /* Copyright (c) University of Cambridge 1995 - 2018 */
+/* Copyright (c) The Exim Maintainers 2020 */
 /* See the file NOTICE for conditions of use and distribution. */
 
 
@@ -463,7 +464,8 @@ code knows to look for them. We count the entries to set the value for the
 queue stripchart, and set up data for the queue display window if the "full"
 option is given. */
 
-void scan_spool_input(int full)
+void
+scan_spool_input(int full)
 {
 int i;
 int subptr;
@@ -471,8 +473,6 @@ int subdir_max = 1;
 int count = 0;
 int indexptr = 1;
 queue_item *p;
-struct dirent *ent;
-DIR *dd;
 uschar input_dir[256];
 uschar subdirs[64];
 
@@ -490,16 +490,18 @@ there is progress, output a dot for each one to the standard output. */
 for (i = 0; i < subdir_max; i++)
   {
   int subdirchar = subdirs[i];      /* 0 for main directory */
+  DIR *dd;
+  struct dirent *ent;
+
   if (subdirchar != 0)
     {
     input_dir[subptr] = '/';
     input_dir[subptr+1] = subdirchar;
     }
 
-  dd = opendir(CS input_dir);
-  if (dd == NULL) continue;
+  if (!(dd = exim_opendir(input_dir))) continue;
 
-  while ((ent = readdir(dd)) != NULL)
+  while ((ent = readdir(dd)))
     {
     uschar *name = US ent->d_name;
     int len = Ustrlen(name);
@@ -543,22 +545,23 @@ removing items, the total that we are comparing against isn't actually correct,
 but in a long queue it won't make much difference, and in a short queue it
 doesn't matter anyway!*/
 
-p = queue_index[0];
-while (p != NULL)
-  {
+for (p = queue_index[0]; p; )
   if (!p->seen)
     {
-    queue_item *next = p->next;
-    if (p->prev == NULL) queue_index[0] = next;
-      else p->prev->next = next;
-    if (next == NULL)
+    queue_item * next = p->next;
+    if (p->prev)
+      p->prev->next = next;
+    else
+      queue_index[0] = next;
+    if (next)
+      next->prev = p->prev;
+    else
       {
       int i;
-      queue_item *q = queue_index[queue_index_size-1];
+      queue_item * q = queue_index[queue_index_size-1];
       for (i = queue_index_size - 1; i >= 0; i--)
         if (queue_index[i] == q) queue_index[i] = p->prev;
       }
-    else next->prev = p->prev;
     clean_up(p);
     queue_total--;
     p = next;
@@ -566,22 +569,17 @@ while (p != NULL)
   else
     {
     if (++count > (queue_total * indexptr)/(queue_index_size-1))
-      {
       queue_index[indexptr++] = p;
-      }
     p->seen = FALSE;  /* for next time */
     p = p->next;
     }
-  }
 
 /* If a lot of messages have been removed at the bottom, we may not
 have got the index all filled in yet. Make sure all the pointers
 are legal. */
 
 while (indexptr < queue_index_size - 1)
-  {
   queue_index[indexptr++] = queue_index[queue_index_size-1];
-  }
 }