Utils: Add a few gdb post-analysis scripts

* SHM troubleshooting: "what are the most recent SHM allocation events
around corrupted address X?"
* TCP conn troubleshooting: "what was the chain of events on connection
 X, which ultimately lead to a crash?"

Author: liviuchircu

utils/gdb/debugging.gdb

@@ -0,0 +1,94 @@
+set pagination off
+set print elements 0
+set max-value-size unlimited
+
+# usage: shm_hist_search 0x7faf32f44900
+#  ... to search for SHM activity near an address of crash (latest -> oldest)
+define shm_hist_search
+
+  set $off = (long)&((struct struct_hist *)0).list
+  set $first_obj = (struct struct_hist *)((char *)shm_hist->objects->prev - $off)
+  set $last_obj = (struct struct_hist *)((char *)shm_hist->objects->next - $off)
+  set $seconds = ($last_obj->created - $first_obj->created) / 1000000
+
+  set $it = shm_hist->objects->next
+  set $cnt = 0
+  set $tot = 0
+  set $hlen = shm_hist->len
+
+  printf "OpenSIPS run time: %d hours, %d mins\n", *jiffies / 3600, (*jiffies % 3600) / 60
+  printf "SHM history objects: %d now, %d all time\n", shm_hist->len, shm_hist->total_obj
+  printf "Oldest SHM history object: %d seconds ago\n", $seconds
+
+  printf "Digging in history for SHM activity close to address: %p ...\n", ($arg0)
+
+  while ($tot < $hlen && $cnt < 100)
+    set $tot = $tot + 1
+
+    set $hist = (struct struct_hist *)((char *)$it - $off)
+    set $p = $hist->obj
+
+    if $p >= ($arg0) - 1000 && $p <= ($arg0)
+      p $hist->obj
+      p *$hist->actions
+      set $cnt = $cnt + 1
+    end
+
+    if $tot % 100 == 0
+      printf "%d objects analyzed so far ...\n", $tot
+    end
+
+    set $it = $it->next
+  end
+end
+
+# usage: tcpcon_hist_search 0x7faf32f44900
+#  ... to search for the history of a given connection (latest -> oldest)
+define tcpcon_hist_search
+
+  set $off = (long)&((struct struct_hist *)0).list
+  set $first_obj = (struct struct_hist *)((char *)con_hist->objects->prev - $off)
+  set $last_obj = (struct struct_hist *)((char *)con_hist->objects->next - $off)
+  set $seconds = ($last_obj->created - $first_obj->created) / 1000000
+
+  set $it = con_hist->objects->next
+  set $tot = 0
+  set $found = 0
+
+  printf "OpenSIPS run time: %d hours, %d mins\n", *jiffies / 3600, (*jiffies % 3600) / 60
+  printf "CON history objects: %d now, %d all time\n", con_hist->len, con_hist->total_obj
+  printf "Oldest CON history object: %d seconds ago\n", $seconds
+
+  printf "Digging in CON histories for connection: %p ...\n", ($arg0)
+
+  while ((long)$it != (long)con_hist->objects && !$found)
+    set $tot = $tot + 1
+
+    set $hist = (struct struct_hist *)((char *)$it - $off)
+    set $con = (struct tcp_connection *)$hist->obj
+
+    if $con == ($arg0)
+      set $found = 1
+
+      printf "Found history for conn: %p\n", $con
+      printf "Total actions: %d, max: %d (all shown below)\n", $hist->len, $hist->max_len
+      printf "-------------------------------------------------\n"
+      set $i = 0
+      while ($i < $hist->max_len)
+        p $hist->actions[$i++]
+      end
+
+      return
+    else
+      if $tot % 100 == 0
+        printf "%d objects analyzed so far ...\n", $tot
+      end
+    end
+
+    set $it = $it->next
+  end
+
+  if !$found
+    printf "ERROR: Failed to locate history for conn %p !\n", ($arg0)
+  end
+end