lib: unstupidify thread debug information

the library's thread scheduling functions keep track of the thread
function's name, so far so good.  However, copying the compiler-provided
constant into a buffer inside the thread structure is plain useless.
Also, strip_funcname() was trying to support something that never
happens.

Instead, let's use some bytes here to track where threads are scheduled
from.  Another commit will print that information on crashes.

Ripping out useless stuff:  -64 bytes in the thread structure
Re-add as const ptr:         +8 bytes
Extra debug info:           +12 bytes

Signed-off-by: David Lamparter <equinox@opensourcerouting.org>
diff --git a/lib/thread.c b/lib/thread.c
index 468edd9..9de5f94 100644
--- a/lib/thread.c
+++ b/lib/thread.c
@@ -267,7 +267,7 @@
   struct cpu_thread_history *new;
   new = XCALLOC (MTYPE_THREAD_STATS, sizeof (struct cpu_thread_history));
   new->func = a->func;
-  strcpy(new->funcname, a->funcname);
+  new->funcname = a->funcname;
   return new;
 }
 
@@ -334,7 +334,7 @@
   void *args[3] = {&tmp, vty, &filter};
 
   memset(&tmp, 0, sizeof tmp);
-  strcpy(tmp.funcname, "TOTAL");
+  tmp.funcname = "TOTAL";
   tmp.types = filter;
 
 #ifdef HAVE_RUSAGE
@@ -582,7 +582,6 @@
   assert (thread->prev == NULL);
   assert (thread->type == THREAD_UNUSED);
   thread_list_add (&m->unuse, thread);
-  /* XXX: Should we deallocate funcname here? */
 }
 
 /* Free all unused thread. */
@@ -663,35 +662,13 @@
     return 0;
 }
 
-/* Trim blankspace and "()"s */
-void
-strip_funcname (char *dest, const char *funcname)
-{
-  char buff[FUNCNAME_LEN];
-  char tmp, *e, *b = buff;
-
-  strncpy(buff, funcname, sizeof(buff));
-  buff[ sizeof(buff) -1] = '\0';
-  e = buff +strlen(buff) -1;
-
-  /* Wont work for funcname ==  "Word (explanation)"  */
-
-  while (*b == ' ' || *b == '(')
-    ++b;
-  while (*e == ' ' || *e == ')')
-    --e;
-  e++;
-
-  tmp = *e;
-  *e = '\0';
-  strcpy (dest, b);
-  *e = tmp;
-}
+#define debugargdef  const char *funcname, const char *schedfrom, int fromln
+#define debugargpass funcname, schedfrom, fromln
 
 /* Get new thread.  */
 static struct thread *
 thread_get (struct thread_master *m, u_char type,
-	    int (*func) (struct thread *), void *arg, const char* funcname)
+	    int (*func) (struct thread *), void *arg, debugargdef)
 {
   struct thread *thread = thread_trim_head (&m->unuse);
 
@@ -707,7 +684,9 @@
   thread->arg = arg;
   thread->index = -1;
 
-  strip_funcname (thread->funcname, funcname);
+  thread->funcname = funcname;
+  thread->schedfrom = schedfrom;
+  thread->schedfrom_line = fromln;
 
   return thread;
 }
@@ -715,7 +694,8 @@
 /* Add new read thread. */
 struct thread *
 funcname_thread_add_read (struct thread_master *m, 
-		 int (*func) (struct thread *), void *arg, int fd, const char* funcname)
+		 int (*func) (struct thread *), void *arg, int fd,
+		 debugargdef)
 {
   struct thread *thread;
 
@@ -727,7 +707,7 @@
       return NULL;
     }
 
-  thread = thread_get (m, THREAD_READ, func, arg, funcname);
+  thread = thread_get (m, THREAD_READ, func, arg, debugargpass);
   FD_SET (fd, &m->readfd);
   thread->u.fd = fd;
   thread_list_add (&m->read, thread);
@@ -738,7 +718,8 @@
 /* Add new write thread. */
 struct thread *
 funcname_thread_add_write (struct thread_master *m,
-		 int (*func) (struct thread *), void *arg, int fd, const char* funcname)
+		 int (*func) (struct thread *), void *arg, int fd,
+		 debugargdef)
 {
   struct thread *thread;
 
@@ -750,7 +731,7 @@
       return NULL;
     }
 
-  thread = thread_get (m, THREAD_WRITE, func, arg, funcname);
+  thread = thread_get (m, THREAD_WRITE, func, arg, debugargpass);
   FD_SET (fd, &m->writefd);
   thread->u.fd = fd;
   thread_list_add (&m->write, thread);
@@ -763,8 +744,8 @@
                                    int (*func) (struct thread *), 
                                   int type,
                                   void *arg, 
-                                  struct timeval *time_relative, 
-                                  const char* funcname)
+                                  struct timeval *time_relative,
+				  debugargdef)
 {
   struct thread *thread;
   struct pqueue *queue;
@@ -776,7 +757,7 @@
   assert (time_relative);
   
   queue = ((type == THREAD_TIMER) ? m->timer : m->background);
-  thread = thread_get (m, type, func, arg, funcname);
+  thread = thread_get (m, type, func, arg, debugargpass);
 
   /* Do we need jitter here? */
   quagga_get_relative (NULL);
@@ -793,7 +774,8 @@
 struct thread *
 funcname_thread_add_timer (struct thread_master *m,
 		           int (*func) (struct thread *), 
-		           void *arg, long timer, const char* funcname)
+		           void *arg, long timer,
+			   debugargdef)
 {
   struct timeval trel;
 
@@ -803,14 +785,15 @@
   trel.tv_usec = 0;
 
   return funcname_thread_add_timer_timeval (m, func, THREAD_TIMER, arg, 
-                                            &trel, funcname);
+                                            &trel, debugargpass);
 }
 
 /* Add timer event thread with "millisecond" resolution */
 struct thread *
 funcname_thread_add_timer_msec (struct thread_master *m,
                                 int (*func) (struct thread *), 
-                                void *arg, long timer, const char* funcname)
+                                void *arg, long timer,
+				debugargdef)
 {
   struct timeval trel;
 
@@ -820,15 +803,15 @@
   trel.tv_usec = 1000*(timer % 1000);
 
   return funcname_thread_add_timer_timeval (m, func, THREAD_TIMER, 
-                                            arg, &trel, funcname);
+                                            arg, &trel, debugargpass);
 }
 
 /* Add a background thread, with an optional millisec delay */
 struct thread *
 funcname_thread_add_background (struct thread_master *m,
                                 int (*func) (struct thread *),
-                                void *arg, long delay, 
-                                const char *funcname)
+                                void *arg, long delay,
+				debugargdef)
 {
   struct timeval trel;
   
@@ -846,19 +829,20 @@
     }
 
   return funcname_thread_add_timer_timeval (m, func, THREAD_BACKGROUND,
-                                            arg, &trel, funcname);
+                                            arg, &trel, debugargpass);
 }
 
 /* Add simple event thread. */
 struct thread *
 funcname_thread_add_event (struct thread_master *m,
-		  int (*func) (struct thread *), void *arg, int val, const char* funcname)
+		  int (*func) (struct thread *), void *arg, int val,
+		  debugargdef)
 {
   struct thread *thread;
 
   assert (m != NULL);
 
-  thread = thread_get (m, THREAD_EVENT, func, arg, funcname);
+  thread = thread_get (m, THREAD_EVENT, func, arg, debugargpass);
   thread->u.val = val;
   thread_list_add (&m->event, thread);
 
@@ -1253,7 +1237,7 @@
       struct cpu_thread_history tmp;
       
       tmp.func = thread->func;
-      strcpy(tmp.funcname, thread->funcname);
+      tmp.funcname = thread->funcname;
       
       thread->hist = hash_get (cpu_record, &tmp, 
                     (void * (*) (void *))cpu_record_hash_alloc);
@@ -1301,7 +1285,7 @@
                 int (*func)(struct thread *), 
                 void *arg,
                 int val,
-		const char* funcname)
+		debugargdef)
 {
   struct thread dummy; 
 
@@ -1313,7 +1297,11 @@
   dummy.func = func;
   dummy.arg = arg;
   dummy.u.val = val;
-  strip_funcname (dummy.funcname, funcname);
+
+  dummy.funcname = funcname;
+  dummy.schedfrom = schedfrom;
+  dummy.schedfrom_line = fromln;
+
   thread_call (&dummy);
 
   return NULL;