Cleanup up stacktrace code

Updated qsort source from glibc.
Add debugging of keycache when EXTRA_DEBUG is specified


Docs/manual.texi:
  Added new contrib stuff
bdb/dist/Makefile.in:
  Don't automaticly checkout things from bk
mysys/mf_keycache.c:
  Add debugging of keycache when EXTRA_DEBUG is specified.
mysys/mf_qsort.c:
  Updated qsort source from glibc.
sql/Makefile.am:
  Cleanup up stacktrace code
sql/mysqld.cc:
  Cleanup up stacktrace code

8 files changed, 442 insertions, 376 deletions

diff --git a/Docs/manual.texi b/Docs/manual.texi
index b3023a905c7..e1bf4045e1a 100644
--- a/Docs/manual.texi
+++ b/Docs/manual.texi
@@ -43451,18 +43451,23 @@ your actual @strong{MySQL} server either way. Free of charge. See
 Created by Laurent Bossavit of NetDIVE.
 @strong{NOTE:} Doesn't work with Access2!
 
-@item @uref{http://www.mysql.com/Downloads/Contrib/msql2mysqlWrapper-1.0.tgz, /msql2mysqlWrapper 1.0}
+@item @uref{http://www.mysql.com/Downloads/Contrib/mdb2sql.bas, mdb2sql.bas}
+Converter from Access97 to @strong{MySQL} by Moshe Gurvich.
+
+@item @uref{http://www.mysql.com/Downloads/Contrib/msql2mysqlWrapper-1.0.tgz, msql2mysqlWrapper 1.0}
 A C wrapper from @code{mSQL} to @strong{MySQL}. By @email{alfred@@sb.net}
 
 @item @uref{http://www.mysql.com/Downloads/Contrib/sqlconv.pl, sqlconv.pl}
-A simple script that can be used to copy fields from one @strong{MySQL} table to
-another in bulk. Basically, you can run @code{mysqldump} and pipe it to
+A simple script that can be used to copy fields from one @strong{MySQL} table
+to another in bulk. Basically, you can run @code{mysqldump} and pipe it to
 the @code{sqlconv.pl} script. The script will parse through the
 @code{mysqldump} output and will rearrange the fields so they can be
 inserted into a new table. An example is when you want to create a new
 table for a different site you are working on, but the table is just a
 bit different (that is - fields in different order, etc.).
 By Steve Shreeve.
+@item @uref{http://www.mysql.com/Downloads/Contrib/oracledump, oracledump}
+Perl program to convert Oracle databases to @strong{MySQL}. By Johan Andersson.
 @end itemize
 
 @appendixsec Using MySQL with Other Products
diff --git a/bdb/dist/Makefile.in b/bdb/dist/Makefile.in
index 73f82cd5648..4a47953e3e1 100644
--- a/bdb/dist/Makefile.in
+++ b/bdb/dist/Makefile.in
@@ -997,3 +997,6 @@ strerror@o@: $(srcdir)/clib/strerror.c
 	$(CC) $(CFLAGS) $?
 vsnprintf@o@: $(srcdir)/clib/vsnprintf.c
 	$(CC) $(CFLAGS) $?
+
+# Don't update the files from bitkeeper
+%::SCCS/s.%
diff --git a/mysys/mf_keycache.c b/mysys/mf_keycache.c
index 71177c4328b..d63ddbf3702 100644
--- a/mysys/mf_keycache.c
+++ b/mysys/mf_keycache.c
@@ -232,7 +232,7 @@ static inline void link_file_to_changed(SEC_LINK *next)
 }
 
 
-#ifndef DBUG_OFF
+#if !defined(DBUG_OFF) && !defined(EXTRA_DEBUG)
 #define DBUG_OFF				/* This should work */
 #endif
 
diff --git a/mysys/mf_qsort.c b/mysys/mf_qsort.c
index e029e148ddb..7074abac96e 100644
--- a/mysys/mf_qsort.c
+++ b/mysys/mf_qsort.c
@@ -1,40 +1,28 @@
-/* Copyright (C) 2000 MySQL AB & MySQL Finland AB & TCX DataKonsult AB
-   
-   This library is free software; you can redistribute it and/or
-   modify it under the terms of the GNU Library General Public
-   License as published by the Free Software Foundation; either
-   version 2 of the License, or (at your option) any later version.
-   
-   This library is distributed in the hope that it will be useful,
+/* Copyright (C) 1991, 1992, 1996, 1997 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Written by Douglas C. Schmidt (schmidt@ics.uci.edu).
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Library General Public License as
+   published by the Free Software Foundation; either version 2 of the
+   License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
    Library General Public License for more details.
-   
-   You should have received a copy of the GNU Library General Public
-   License along with this library; if not, write to the Free
-   Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
-   MA 02111-1307, USA */
-
-/* Plug-compatible replacement for UNIX qsort.
-   Copyright (C) 1989 Free Software Foundation, Inc.
-   Written by Douglas C. Schmidt (schmidt@ics.uci.edu)
-   Optimized and modyfied for mysys by monty.
 
-This file is part of GNU CC.
-
-GNU QSORT is free software; you can redistribute it and/or modify
-it under the terms of the GNU General Public License as published by
-the Free Software Foundation; either version 1, or (at your option)
-any later version.
-
-GNU QSORT is distributed in the hope that it will be useful,
-but WITHOUT ANY WARRANTY; without even the implied warranty of
-MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-GNU General Public License for more details.
+   You should have received a copy of the GNU Library General Public
+   License along with the GNU C Library; see the file COPYING.LIB.  If not,
+   write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+   Boston, MA 02111-1307, USA.	*/
 
-You should have received a copy of the GNU General Public License
-along with GNU QSORT; see the file COPYING.  If not, write to
-the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */
+/*
+    Modifications by monty:
+  - Uses mysys include files
+  - Small fixes to make the it a bit faster
+  - Can be compiled with a cmp function that takes one extra argument.
+*/
 
 #include "mysys_priv.h"
 
@@ -46,32 +34,36 @@ the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */
 #endif
 
 /* Byte-wise swap two items of size SIZE. */
-#define SWAP(A,B,SIZE) do {int sz=(int)(SIZE); char *a = (A); char *b = (B); \
-    do { char _temp = *a;*a++ = *b;*b++ = _temp;} while (--sz);} while (0)
+#define SWAP(a, b, size)						      \
+  do									      \
+    {									      \
+      register size_t __size = (size);					      \
+      register char *__a = (a), *__b = (b);				      \
+      do								      \
+	{								      \
+	  char __tmp = *__a;						      \
+	  *__a++ = *__b;						      \
+	  *__b++ = __tmp;						      \
+	} while (--__size > 0);						      \
+    } while (0)
 
-/* Copy SIZE bytes from item B to item A. */
-#define COPY(A,B,SIZE) {int sz = (int) (SIZE); do { *(A)++ = *(B)++; } while (--sz); }
+/* Discontinue quicksort algorithm when partition gets below this size.
+   This particular magic number was chosen to work best on a Sun 4/260. */
+#define MAX_THRESH 8
 
-/* This should be replaced by a standard ANSI macro. */
-#define BYTES_PER_WORD 8
+/* Stack node declarations used to store unfulfilled partition obligations. */
+typedef struct
+  {
+    char *lo;
+    char *hi;
+  } stack_node;
 
 /* The next 4 #defines implement a very fast in-line stack abstraction. */
-#define STACK_SIZE (BYTES_PER_WORD * sizeof (long))
+#define STACK_SIZE	(8 * sizeof(unsigned long int))
 #define PUSH(LOW,HIGH) do {top->lo = LOW;top++->hi = HIGH;} while (0)
 #define POP(LOW,HIGH)  do {LOW = (--top)->lo;HIGH = top->hi;} while (0)
 #define STACK_NOT_EMPTY (stack < top)
 
-/* Discontinue quicksort algorithm when partition gets below this size.
-   This particular magic number was chosen to work best on a Sparc SLC. */
-#define MAX_THRESH 12
-
-/* Stack node declarations used to store unfulfilled partition obligations. */
-typedef struct
-{
-  char *lo;
-  char *hi;
-} stack_node;
-
 /* Order size using quicksort.	This implementation incorporates
    four optimizations discussed in Sedgewick:
 
@@ -88,7 +80,7 @@ typedef struct
    3. Only quicksorts TOTAL_ELEMS / MAX_THRESH partitions, leaving
       insertion sort to order the MAX_THRESH items within each partition.
       This is a big win, since insertion sort is faster for small, mostly
-      sorted array segements.
+      sorted array segments.
 
    4. The larger of the two sub-partitions is always pushed onto the
       stack first, with the algorithm then concentrating on the
@@ -111,100 +103,98 @@ qsort_t qsort(void *base_ptr, size_t total_elems, size_t size, qsort_cmp cmp)
   /* Allocating SIZE bytes for a pivot buffer facilitates a better
      algorithm below since we can do comparisons directly on the pivot.
      */
-  int	max_thresh   = (int) (MAX_THRESH * size);
+  size_t max_thresh   = (size_t) (MAX_THRESH * size);
   if (total_elems <= 1)
     SORT_RETURN;		/* Crashes on MSDOS if continues */
 
   if (total_elems > MAX_THRESH)
   {
     char       *lo = base_ptr;
-    char       *hi = lo + size * (total_elems - 1);
+    char       *hi = &lo[size * (total_elems - 1)];
     stack_node stack[STACK_SIZE]; /* Largest size needed for 32-bit int!!! */
     stack_node *top = stack + 1;
-    char *pivot_buffer = (char *) my_alloca ((int) size);
+    char *pivot = (char *) my_alloca ((int) size);
 #ifdef HAVE_purify
     stack[0].lo=stack[0].hi=0;
 #endif
 
-    while (STACK_NOT_EMPTY)
+    do
     {
-      char *left_ptr;
-      char *right_ptr;
+      char *left_ptr,*right_ptr;
+
+      /* Select median value from among LO, MID, and HI. Rearrange
+	 LO and HI so the three values are sorted. This lowers the
+	 probability of picking a pathological pivot value and
+	 skips a comparison for both the LEFT_PTR and RIGHT_PTR. */
+
+      char *mid = lo + size * (((ulong) (hi - lo) / (ulong) size) >> 1);
+
+      if (CMP(hi,lo) < 0)
+	SWAP (hi, lo, size);
+      if (CMP (mid, lo) < 0)
+	SWAP (mid, lo, size);
+      else if (CMP (hi, mid) < 0)
+	SWAP (mid, hi, size);
+      memcpy (pivot, mid, size);
+
+      left_ptr	= lo + size;
+      right_ptr = hi - size;
+
+      /* Here's the famous ``collapse the walls'' section of quicksort.
+	 Gotta like those tight inner loops!	They are the main reason
+	 that this algorithm runs much faster than others. */
+      do
       {
-	char *pivot = pivot_buffer;
+	while (CMP (left_ptr, pivot) < 0)
+	  left_ptr += size;
+
+	while (CMP (pivot, right_ptr) < 0)
+	  right_ptr -= size;
+
+	if (left_ptr < right_ptr)
 	{
-	  /* Select median value from among LO, MID, and HI. Rearrange
-	     LO and HI so the three values are sorted. This lowers the
-	     probability of picking a pathological pivot value and
-	     skips a comparison for both the LEFT_PTR and RIGHT_PTR. */
-
-	  char *mid = lo + size * (((uint) (hi - lo) / (uint) size) >> 1);
-
-	  if (CMP(hi,lo) < 0)
-	    SWAP (hi, lo, size);
-	  if (CMP (mid, lo) < 0)
-	    SWAP (mid, lo, size);
-	  else if (CMP (hi, mid) < 0)
-	    SWAP (mid, hi, size);
-	  COPY (pivot, mid, size);
-	  pivot = pivot_buffer;
+	  SWAP (left_ptr, right_ptr, size);
+	  left_ptr += size;
+	  right_ptr -= size;
 	}
-	left_ptr  = lo + size;
-	right_ptr = hi - size;
-
-	/* Here's the famous ``collapse the walls'' section of quicksort.
-	   Gotta like those tight inner loops!	They are the main reason
-	   that this algorithm runs much faster than others. */
-	do
+	else if (left_ptr == right_ptr)
 	{
-	  while (CMP (left_ptr, pivot) < 0)
-	    left_ptr += size;
-
-	  while (CMP (pivot, right_ptr) < 0)
-	    right_ptr -= size;
-
-	  if (left_ptr < right_ptr)
-	  {
-	    SWAP (left_ptr, right_ptr, size);
-	    left_ptr += size;
-	    right_ptr -= size;
-	  }
-	  else if (left_ptr == right_ptr)
-	  {
-	    left_ptr += size;
-	    right_ptr -= size;
-	    break;
-	  }
+	  left_ptr += size;
+	  right_ptr -= size;
+	  break;
 	}
-	while (left_ptr <= right_ptr);
+	else
+	  break;				/* left_ptr > right_ptr */
       }
+      while (left_ptr <= right_ptr);
+
 
       /* Set up pointers for next iteration.  First determine whether
 	 left and right partitions are below the threshold size. If so,
 	 ignore one or both.  Otherwise, push the larger partition's
 	 bounds on the stack and continue sorting the smaller one. */
 
-      if ((right_ptr - lo) <= max_thresh)
+      if ((size_t) (right_ptr - lo) <= max_thresh)
       {
-	if ((hi - left_ptr) <= max_thresh)	/* Ignore both small parts. */
-	  POP (lo, hi);
-	else					/* Ignore small left part. */
-	  lo = left_ptr;
+	if ((size_t) (hi - left_ptr) <= max_thresh)
+	  POP (lo, hi);			/* Ignore both small partitions. */
+	else
+	  lo = left_ptr;		/* Ignore small left part. */
       }
-      else if ((hi - left_ptr) <= max_thresh)	/* Ignore small right part. */
-	hi = right_ptr;
-      else if ((right_ptr - lo) > (hi - left_ptr)) /* Push larger left part */
+      else if ((size_t) (hi - left_ptr) <= max_thresh)
+	hi = right_ptr;			/* Ignore small right partition. */
+      else if ((right_ptr - lo) > (hi - left_ptr))
       {
-	PUSH (lo, right_ptr);
+	PUSH (lo, right_ptr);		/* Push larger left part */
 	lo = left_ptr;
       }
-      else					/* Push larger right part */
+      else
       {
-	PUSH (left_ptr, hi);
+	PUSH (left_ptr, hi);		/* Push larger right part */
 	hi = right_ptr;
       }
-    }
-    my_afree(pivot_buffer);
+    } while (STACK_NOT_EMPTY);
+    my_afree(pivot);
   }
 
   /* Once the BASE_PTR array is partially sorted by quicksort the rest
@@ -215,9 +205,9 @@ qsort_t qsort(void *base_ptr, size_t total_elems, size_t size, qsort_cmp cmp)
 
   {
     char *end_ptr = (char*) base_ptr + size * (total_elems - 1);
-    char *run_ptr;
     char *tmp_ptr = (char*) base_ptr;
     char *thresh  = min (end_ptr, (char*) base_ptr + max_thresh);
+    register char *run_ptr;
 
     /* Find smallest element in first threshold and place it at the
        array's beginning.  This is the smallest array element,
@@ -230,18 +220,18 @@ qsort_t qsort(void *base_ptr, size_t total_elems, size_t size, qsort_cmp cmp)
     if (tmp_ptr != (char*) base_ptr)
       SWAP (tmp_ptr, (char*) base_ptr, size);
 
-    /* Insertion sort, running from left-hand-side up to `right-hand-side.'
-       Pretty much straight out of the original GNU qsort routine. */
+    /* Insertion sort, running from left-hand-side up to right-hand-side.  */
 
     for (run_ptr = (char*) base_ptr + size;
-	 (tmp_ptr = run_ptr += size) <= end_ptr; )
+	 (run_ptr += size) <= end_ptr; )
     {
-      while (CMP (run_ptr, tmp_ptr -= size) < 0) ;
-
-      if ((tmp_ptr += size) != run_ptr)
+      if (CMP (run_ptr, (tmp_ptr = run_ptr-size)) < 0)
       {
 	char *trav;
+	while (CMP (run_ptr, tmp_ptr -= size) < 0) ;
+	tmp_ptr += size;
 
+	/* Shift down all smaller elements, put found element in 'run_ptr' */
 	for (trav = run_ptr + size; --trav >= run_ptr;)
 	{
 	  char c = *trav;
@@ -252,7 +242,6 @@ qsort_t qsort(void *base_ptr, size_t total_elems, size_t size, qsort_cmp cmp)
 	  *hi = c;
 	}
       }
-
     }
   }
   SORT_RETURN;
diff --git a/sql/Makefile.am b/sql/Makefile.am
index 596a1d3acf7..774ef06f17c 100644
--- a/sql/Makefile.am
+++ b/sql/Makefile.am
@@ -54,7 +54,8 @@ noinst_HEADERS =	item.h item_func.h item_sum.h item_cmpfunc.h \
 			ha_gemini.h opt_range.h opt_ft.h \
 			sql_select.h structs.h table.h sql_udf.h hash_filo.h\
 			lex.h lex_symbol.h sql_acl.h sql_crypt.h md5.h \
-                        log_event.h mini_client.h sql_repl.h slave.h
+                        log_event.h mini_client.h sql_repl.h slave.h \
+			stacktrace.h
 mysqld_SOURCES =	sql_lex.cc \
 			item.cc item_sum.cc item_buff.cc item_func.cc \
 			item_cmpfunc.cc item_strfunc.cc item_timefunc.cc \
@@ -67,17 +68,19 @@ mysqld_SOURCES =	sql_lex.cc \
 			sql_base.cc table.cc sql_select.cc sql_insert.cc \
 			sql_update.cc sql_delete.cc \
 			procedure.cc item_uniq.cc sql_test.cc \
-			log.cc init.cc derror.cc sql_acl.cc unireg.cc \
+			log.cc log_event.cc init.cc derror.cc sql_acl.cc \
+			unireg.cc \
 			time.cc opt_range.cc opt_sum.cc opt_ft.cc \
 		   	records.cc filesort.cc handler.cc \
-		        ha_isam.cc ha_isammrg.cc ha_heap.cc \
-			ha_myisam.cc ha_myisammrg.cc ha_berkeley.cc \
-	                ha_innobase.cc ha_gemini.cc \
+		        ha_heap.cc ha_myisam.cc ha_myisammrg.cc \
+	                ha_berkeley.cc ha_innobase.cc ha_gemini.cc \
+			ha_isam.cc ha_isammrg.cc \
 			sql_db.cc sql_table.cc sql_rename.cc sql_crypt.cc \
 			sql_load.cc mf_iocache.cc field_conv.cc sql_show.cc \
 			sql_udf.cc sql_analyse.cc sql_analyse.h sql_cache.cc \
 			slave.cc sql_repl.cc \
-			md5.c log_event.cc mini_client.cc mini_client_errors.c
+			mini_client.cc mini_client_errors.c \
+			md5.c stacktrace.c
 gen_lex_hash_SOURCES =	gen_lex_hash.cc
 gen_lex_hash_LDADD =	$(LDADD) $(CXXLDFLAGS)
 mysqlbinlog_SOURCES =   mysqlbinlog.cc mini_client.cc net_serv.cc \
diff --git a/sql/mysqld.cc b/sql/mysqld.cc
index 503a45a8da0..c9e19b65a6c 100644
--- a/sql/mysqld.cc
+++ b/sql/mysqld.cc
@@ -20,6 +20,7 @@
 #include <my_dir.h>
 #include "sql_acl.h"
 #include "slave.h"
+#include "stacktrace.h"
 #ifdef HAVE_BERKELEY_DB
 #include "ha_berkeley.h"
 #endif
@@ -1125,236 +1126,33 @@ static void start_signal_handler(void)
 #else /* if ! __WIN__ && ! __EMX__ */
 
 #ifdef HAVE_LINUXTHREADS
-static sig_handler write_core(int sig);
-
-#if defined (__i386__) || (defined(__alpha__) && defined(__GNUC__))
-#define LINUX_STACK_TRACE
-#endif
-
-#ifdef LINUX_STACK_TRACE
-#define PTR_SANE(p) ((p) && (char*)(p) >= heap_start && (char*)(p) <= heap_end)
-
-extern char* __bss_start;
-static char* heap_start, *heap_end;
-
-inline __volatile__ void print_str(const char* name,
-				   const char* val, int max_len)
-{
-  fprintf(stderr, "%s at %p ", name, val);
-  if(!PTR_SANE(val))
-    {
-      fprintf(stderr, " is invalid pointer\n");
-      return;
-    }
-
-  fprintf(stderr, "= ");
-  for(; max_len && PTR_SANE(val) && *val; --max_len)
-    fputc(*val++, stderr);
-  fputc('\n', stderr);
-}
-#endif
-
-
-#ifdef LINUX_STACK_TRACE
-#define SIGRETURN_FRAME_COUNT  1
-
-#if defined(__alpha__) && defined(__GNUC__)
-/*
-  The only way to backtrace without a symbol table on alpha
-  is to find stq fp,N(sp), and the first byte
-  of the instruction opcode will give us the value of N. From this
-  we can find where the old value of fp is stored
-*/
-
-#define MAX_INSTR_IN_FUNC  10000
-
-inline uchar** find_prev_fp(uint32* pc, uchar** fp)
-{
-  int i;
-  for(i = 0; i < MAX_INSTR_IN_FUNC; ++i,--pc)
-    {
-      uchar* p = (uchar*)pc;
-      if(p[2] == 222 &&  p[3] == 35)
-	{
-	  return (uchar**)((uchar*)fp - *(short int*)p);
-	}
-    }
-  return 0;
-}
-
-inline uint32* find_prev_pc(uint32* pc, uchar** fp)
-{
-  int i;
-  for(i = 0; i < MAX_INSTR_IN_FUNC; ++i,--pc)
-    {
-      char* p = (char*)pc;
-      if(p[1] == 0 && p[2] == 94 &&  p[3] == -73)
-	{
-	  uint32* prev_pc = (uint32*)*((fp+p[0]/sizeof(fp)));
-	  return prev_pc;
-	}
-    }
-  return 0;
-}
-
-#endif
-
-inline __volatile__ void  trace_stack()
-{
-  uchar **stack_bottom;
-  uchar** fp;
-  LINT_INIT(fp);
-  LINT_INIT(stack_bottom);
-
-  fprintf(stderr,
-"Attempting backtrace. You can use the following information to find out\n\
-where mysqld died. If you see no messages after this, something went\n\
-terribly wrong...\n");
-  THD* thd = current_thd;
-  uint frame_count = 0;
-#ifdef __i386__  
-  __asm __volatile__ ("movl %%ebp,%0"
-		      :"=r"(fp)
-		      :"r"(fp));
-  if (!fp)
-  {
-    fprintf(stderr, "frame pointer (ebp) is NULL, did you compile with\n\
--fomit-frame-pointer? Aborting backtrace!\n");
-    return;
-  }
-#endif
-#if defined(__alpha__) && defined(__GNUC__) 
-  __asm __volatile__ ("mov $15,%0"
-		      :"=r"(fp)
-		      :"r"(fp));
-  if (!fp)
-  {
-    fprintf(stderr, "frame pointer (fp) is NULL, did you compile with\n\
--fomit-frame-pointer? Aborting backtrace!\n");
-    return;
-  }
-#endif /* __alpha__ */
-  
-  if (!thd)
-  {
-    fprintf(stderr, "Cannot determine thread, fp=%p, backtrace may not be correct.\n", fp);
-    /* Assume that the stack starts at the previous even 65K */
-    ulong tmp= min(0x10000,thread_stack);
-    stack_bottom= (uchar**) (((ulong) &stack_bottom + tmp) &
-			     ~(ulong) 0xFFFF);
-  }
-  else
-    stack_bottom = (uchar**) thd->thread_stack;
-  if (fp > stack_bottom || fp < stack_bottom - thread_stack)
-  {
-    fprintf(stderr, "Bogus stack limit or frame pointer,\
- fp=%p, stack_bottom=%p, thread_stack=%ld, aborting backtrace.\n",
-	    fp, stack_bottom, thread_stack);
-    return;
-  }
-
-  fprintf(stderr, "Stack range sanity check OK, backtrace follows:\n");
-#if defined(__alpha__) && defined(__GNUC__)
-  fprintf(stderr, "Warning: Alpha stacks are difficult -\
- will be taking some wild guesses, stack trace may be incorrect or \
- terminate abruptly\n");
-  // On Alpha, we need to get pc
-  uint32* pc;
-  __asm __volatile__ ("bsr %0, do_next; do_next: "
-		      :"=r"(pc)
-		      :"r"(pc));
-#endif  /* __alpha__ */
-  
-  while (fp < stack_bottom)
-  {
-#ifdef __i386__    
-    uchar** new_fp = (uchar**)*fp;
-    fprintf(stderr, "%p\n", frame_count == SIGRETURN_FRAME_COUNT ?
-	    *(fp+17) : *(fp+1));
-#endif
-#if defined(__alpha__) && defined(__GNUC__)
-    uchar** new_fp = find_prev_fp(pc, fp);
-    if(frame_count == SIGRETURN_FRAME_COUNT - 1)
-      {
-        new_fp += 90;
-      }
-    
-    if(fp && pc)
-      {
-        pc = find_prev_pc(pc, fp);
-	if(pc)
-          fprintf(stderr, "%p\n", pc);
-	else
-	  {
-	    fprintf(stderr, "Not smart enough to deal with the rest\
- of this stack\n");
-             goto print_glob_vars;
-	  }
-      }
-    else
-      {
-	fprintf(stderr, "Not smart enough to deal with the rest of\
- this stack\n");
-        goto print_glob_vars;
-      }
-#endif    
-    if (new_fp <= fp )
-    {
-      fprintf(stderr, "New value of fp=%p failed sanity check,\
- terminating stack trace!\n", new_fp);
-      goto print_glob_vars;
-    }
-    fp = new_fp;
-    ++frame_count;
-  }
-
-  fprintf(stderr, "Stack trace seems successful - bottom reached\n");
-    
- print_glob_vars:
-  fprintf(stderr, "Please read http://www.mysql.com/doc/U/s/Using_stack_trace.html and follow instructions on how to resolve the stack trace. Resolved\n\
-stack trace is much more helpful in diagnosing the problem, so please do \n\
-resolve it\n");
-  fprintf(stderr, "Trying to get some variables.\n\
-Some pointers may be invalid and cause the dump to abort...\n");
-  heap_end = (char*)sbrk(0);
-  print_str("thd->query", thd->query, 1024);
-  fprintf(stderr, "thd->thread_id = %ld\n", thd->thread_id);
-  fprintf(stderr, "Successfully dumped variables, if you ran with --log,\n\
-take a look at the details of what thread %ld did to cause the crash.\n\
-In some cases of really bad corruption, this value may be invalid\n",
-	  thd->thread_id);
-  fprintf(stderr, "Please use the information above to create a repeatable\n\
-test case for the crash, and send it to bugs@lists.mysql.com\n");
-}
-#endif
-#endif
-
-#ifdef HAVE_LINUXTHREADS
 #define UNSAFE_DEFAULT_LINUX_THREADS 200
 #endif
 
 static sig_handler handle_segfault(int sig)
 {
+  THD *thd=current_thd;
   // strictly speaking, one needs a mutex here
   // but since we have got SIGSEGV already, things are a mess
   // so not having the mutex is not as bad as possibly using a buggy
   // mutex - so we keep things simple
   if (segfaulted)
-    {
-      fprintf(stderr, "Fatal signal %d while backtracing\n", sig);
-      exit(1);
-    }
+  {
+    fprintf(stderr, "Fatal signal %d while backtracing\n", sig);
+    exit(1);
+  }
   
   segfaulted = 1;
   fprintf(stderr,"\
 mysqld got signal %d;\n\
-This could be because you hit a bug. It is also possible that \n\
-this binary or one of the libraries it was linked agaist is \n\
-corrupt, improperly built, or misconfigured. This error can also be\n\
-caused by malfunctioning hardware.", sig);
-  fprintf(stderr, "We will try our best to scrape up some info\n\
-that will hopefully help diagnose the problem, but since we have already\n\
-crashed, something is definitely wrong and this may fail\n");
+This could be because you hit a bug. It is also possible that this binary\n\
+or one of the libraries it was linked agaist is corrupt, improperly built,\n\
+or misconfigured. This error can also be caused by malfunctioning hardware.\n",
+	  sig);
+  fprintf(stderr, "\
+We will try our best to scrape up some info that will hopefully help diagnose\n\
+the problem, but since we have already crashed, something is definitely wrong\n\
+and this may fail\n\n");
   fprintf(stderr, "key_buffer_size=%ld\n", keybuff_size);
   fprintf(stderr, "record_buffer=%ld\n", my_default_record_cache_size);
   fprintf(stderr, "sort_buffer=%ld\n", sortbuff_size);
@@ -1365,42 +1163,47 @@ crashed, something is definitely wrong and this may fail\n");
 key_buffer_size + (record_buffer + sort_buffer)*max_connections = %ld K\n\
 bytes of memory\n", (keybuff_size + (my_default_record_cache_size +
 			     sortbuff_size) * max_connections)/ 1024);
-  fprintf(stderr, "Hope that's ok, if not, decrease some variables in the\n\
-equation\n");
+  fprintf(stderr, "Hope that's ok, if not, decrease some variables in the equation\n\n");
   
 #if defined(HAVE_LINUXTHREADS)
+  if (sizeof(char*) == 4 && thread_count > UNSAFE_DEFAULT_LINUX_THREADS)
+  {
+    fprintf(stderr, "\
+You seem to be running 32-bit Linux and have %d concurrent connections.\n\
+If you have not changed STACK_SIZE in LinuxThreads and build the binary \n\
+yourself, LinuxThreads is quite likely to steal a part of global heap for\n\
+the thread stack. Please read http://www.mysql.com/doc/L/i/Linux.html\n\n",
+	    thread_count);
+  }
+#endif /* HAVE_LINUXTHREADS */
 
-  if(sizeof(char*) == 4 && thread_count > UNSAFE_DEFAULT_LINUX_THREADS)
-    {
-      fprintf(stderr, "You seem to be running 32-bit Linux and\n\
- have %d concurrent connections. If you have not\n\
-changed STACK_SIZE in LinuxThreads and build the binary yourself,\n\
-LinuxThreads is quite likely to steal a part of global heap for a \n\
-thread stack. Please read http://www.mysql.com/doc/L/i/Linux.html\n",
-	      thread_count);
-    }
-#ifdef LINUX_STACK_TRACE
+#ifdef HAVE_STACKTRACE
   if(!(test_flags & TEST_NO_STACKTRACE))
-    trace_stack();
+    print_stacktrace(thd ? (gptr) thd->thread_stack : (gptr) 0,
+		     thread_stack);
+  if (thd)
+  {
+    fprintf(stderr, "Trying to get some variables.\n\
+Some pointers may be invalid and cause the dump to abort...\n");
+    safe_print_str("thd->query", thd->query, 1024);
+    fprintf(stderr, "thd->thread_id=%ld\n", thd->thread_id);
+    fprintf(stderr, "\n
+Successfully dumped variables, if you ran with --log, take a look at the\n\
+details of what thread %ld did to cause the crash.  In some cases of really\n\
+bad corruption, the above values may be invalid\n\n",
+	  thd->thread_id);
+  }
+  fprintf(stderr, "\
+Please use the information above to create a repeatable test case for the\n\
+crash, and send it to bugs@lists.mysql.com\n");
   fflush(stderr);
-#endif /* LINUX_STACK_TRACE */
+#endif /* HAVE_STACKTRACE */
+
  if (test_flags & TEST_CORE_ON_SIGNAL)
    write_core(sig);
-#endif /* HAVE_LINUXTHREADS */
  exit(1);
 }
 
-/* Produce a core for the thread */
-
-#ifdef HAVE_LINUXTHREADS
-static sig_handler write_core(int sig)
-{
-  signal(sig, SIG_DFL);
-  if (fork() != 0) exit(1);			// Abort main program
-  // Core will be written at exit
-}
-#endif
-
 
 static void init_signals(void)
 {
@@ -1413,12 +1216,9 @@ static void init_signals(void)
   sigemptyset(&sa.sa_mask);
   sigprocmask(SIG_SETMASK,&sa.sa_mask,NULL);
 
-#ifdef LINUX_STACK_TRACE
-  heap_start = (char*)&__bss_start;
-#endif
-  
   if (!(test_flags & TEST_NO_STACKTRACE) || (test_flags & TEST_CORE_ON_SIGNAL))
   {
+    init_stacktrace();
     sa.sa_handler=handle_segfault;
     sigaction(SIGSEGV, &sa, NULL);
 #ifdef SIGBUS
diff --git a/sql/stacktrace.c b/sql/stacktrace.c
new file mode 100644
index 00000000000..ba5bc9d2e85
--- /dev/null
+++ b/sql/stacktrace.c
@@ -0,0 +1,215 @@
+/* Copyright (C) 2000 MySQL AB
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 2 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program; if not, write to the Free Software
+   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA */
+
+#include <global.h>
+#include "stacktrace.h"
+#include <signal.h>
+
+#ifdef HAVE_STACKTRACE
+#include <unistd.h>
+
+#define PTR_SANE(p) ((p) && (char*)(p) >= heap_start && (char*)(p) <= heap_end)
+
+char *heap_start;
+
+void safe_print_str(const char* name, const char* val, int max_len)
+{
+  char *heap_end= (char*) sbrk(0);
+  fprintf(stderr, "%s at %p ", name, val);
+
+  if (!PTR_SANE(val))
+  {
+    fprintf(stderr, " is invalid pointer\n");
+    return;
+  }
+
+  fprintf(stderr, "= ");
+  for(; max_len && PTR_SANE(val) && *val; --max_len)
+    fputc(*val++, stderr);
+  fputc('\n', stderr);
+}
+
+#ifdef HAVE_LINUXTHREADS
+#define SIGRETURN_FRAME_COUNT  1
+
+#if defined(__alpha__) && defined(__GNUC__)
+/*
+  The only way to backtrace without a symbol table on alpha
+  is to find stq fp,N(sp), and the first byte
+  of the instruction opcode will give us the value of N. From this
+  we can find where the old value of fp is stored
+*/
+
+#define MAX_INSTR_IN_FUNC  10000
+
+inline uchar** find_prev_fp(uint32* pc, uchar** fp)
+{
+  int i;
+  for(i = 0; i < MAX_INSTR_IN_FUNC; ++i,--pc)
+  {
+    uchar* p = (uchar*)pc;
+    if (p[2] == 222 &&  p[3] == 35)
+    {
+      return (uchar**)((uchar*)fp - *(short int*)p);
+    }
+  }
+  return 0;
+}
+
+inline uint32* find_prev_pc(uint32* pc, uchar** fp)
+{
+  int i;
+  for(i = 0; i < MAX_INSTR_IN_FUNC; ++i,--pc)
+  {
+    char* p = (char*)pc;
+    if (p[1] == 0 && p[2] == 94 &&  p[3] == -73)
+    {
+      uint32* prev_pc = (uint32*)*((fp+p[0]/sizeof(fp)));
+      return prev_pc;
+    }
+  }
+  return 0;
+}
+#endif /* defined(__alpha__) && defined(__GNUC__) */
+
+
+void  print_stacktrace(gptr stack_bottom, ulong thread_stack)
+{
+  uchar** fp;
+  uint frame_count = 0;
+#if defined(__alpha__) && defined(__GNUC__)
+  uint32* pc;
+#endif
+  LINT_INIT(fp);
+
+  fprintf(stderr,"\
+Attempting backtrace. You can use the following information to find out\n\
+where mysqld died. If you see no messages after this, something went\n\
+terribly wrong...\n");
+#ifdef __i386__  
+  __asm __volatile__ ("movl %%ebp,%0"
+		      :"=r"(fp)
+		      :"r"(fp));
+  if (!fp)
+  {
+    fprintf(stderr, "frame pointer (ebp) is NULL, did you compile with\n\
+-fomit-frame-pointer? Aborting backtrace!\n");
+    return;
+  }
+#endif
+#if defined(__alpha__) && defined(__GNUC__) 
+  __asm __volatile__ ("mov $15,%0"
+		      :"=r"(fp)
+		      :"r"(fp));
+  if (!fp)
+  {
+    fprintf(stderr, "frame pointer (fp) is NULL, did you compile with\n\
+-fomit-frame-pointer? Aborting backtrace!\n");
+    return;
+  }
+#endif /* __alpha__ */
+  
+  if (!stack_bottom)
+  {
+    ulong tmp= min(0x10000,thread_stack);
+    /* Assume that the stack starts at the previous even 65K */
+    stack_bottom= (gptr) (((ulong) &fp + tmp) &
+			  ~(ulong) 0xFFFF);
+    fprintf(stderr, "Cannot determine thread, fp=%p, backtrace may not be correct.\n", fp);
+  }
+  if (fp > (uchar**) stack_bottom ||
+      fp < (uchar**) stack_bottom - thread_stack)
+  {
+    fprintf(stderr, "Bogus stack limit or frame pointer,\
+ fp=%p, stack_bottom=%p, thread_stack=%ld, aborting backtrace.\n",
+	    fp, stack_bottom, thread_stack);
+    return;
+  }
+
+  fprintf(stderr, "Stack range sanity check OK, backtrace follows:\n");
+#if defined(__alpha__) && defined(__GNUC__)
+  fprintf(stderr, "Warning: Alpha stacks are difficult -\
+ will be taking some wild guesses, stack trace may be incorrect or \
+ terminate abruptly\n");
+  // On Alpha, we need to get pc
+  __asm __volatile__ ("bsr %0, do_next; do_next: "
+		      :"=r"(pc)
+		      :"r"(pc));
+#endif  /* __alpha__ */
+  
+  while (fp < (uchar**) stack_bottom)
+  {
+#ifdef __i386__    
+    uchar** new_fp = (uchar**)*fp;
+    fprintf(stderr, "%p\n", frame_count == SIGRETURN_FRAME_COUNT ?
+	    *(fp+17) : *(fp+1));
+#endif /* __386__ */
+
+#if defined(__alpha__) && defined(__GNUC__)
+    uchar** new_fp = find_prev_fp(pc, fp);
+    if (frame_count == SIGRETURN_FRAME_COUNT - 1)
+    {
+      new_fp += 90;
+    }
+    
+    if (fp && pc)
+    {
+      pc = find_prev_pc(pc, fp);
+      if (pc)
+	fprintf(stderr, "%p\n", pc);
+      else
+      {
+	fprintf(stderr, "Not smart enough to deal with the rest\
+ of this stack\n");
+	goto end;
+      }
+    }
+    else
+    {
+      fprintf(stderr, "Not smart enough to deal with the rest of this stack\n");
+      goto end;
+    }
+#endif /* defined(__alpha__) && defined(__GNUC__) */
+    if (new_fp <= fp )
+    {
+      fprintf(stderr, "New value of fp=%p failed sanity check,\
+ terminating stack trace!\n", new_fp);
+      goto end;
+    }
+    fp = new_fp;
+    ++frame_count;
+  }
+
+  fprintf(stderr, "Stack trace seems successful - bottom reached\n");
+    
+end:
+  fprintf(stderr, "Please read http://www.mysql.com/doc/U/s/Using_stack_trace.html and follow instructions on how to resolve the stack trace. Resolved\n\
+stack trace is much more helpful in diagnosing the problem, so please do \n\
+resolve it\n");
+}
+#endif /* HAVE_LINUXTHREADS */
+#endif /* HAVE_STACKTRACE */
+
+/* Produce a core for the thread */
+
+#ifdef HAVE_WRITE_CORE
+void write_core(int sig)
+{
+  signal(sig, SIG_DFL);
+  if (fork() != 0) exit(1);			// Abort main program
+  // Core will be written at exit
+}
+#endif /* HAVE_WRITE_CORE */
diff --git a/sql/stacktrace.h b/sql/stacktrace.h
new file mode 100644
index 00000000000..b6c0ec43a0f
--- /dev/null
+++ b/sql/stacktrace.h
@@ -0,0 +1,51 @@
+/* Copyright (C) 2000 MySQL AB
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 2 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program; if not, write to the Free Software
+   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA */
+
+#ifdef	__cplusplus
+extern "C" {
+#endif
+
+#ifdef HAVE_LINUXTHREADS
+#if defined(HAVE_STACKTRACE) || (defined (__i386__) || (defined(__alpha__) && defined(__GNUC__)))
+#undef HAVE_STACKTRACE
+#define HAVE_STACKTRACE
+
+extern char* __bss_start;
+extern char* heap_start;
+
+#define init_stacktrace() { heap_start = (char*) &__bss_start; }
+void print_stacktrace(gptr stack_bottom, ulong thread_stack);
+void safe_print_str(const char* name, const char* val, int max_len);
+#endif /* (defined (__i386__) || (defined(__alpha__) && defined(__GNUC__))) */
+
+#define HAVE_WRITE_CORE
+void write_core(int sig);
+#endif /* HAVE_LINUXTHREADS */
+
+/* Define empty prototypes for functions that are not implemented */
+#ifndef HAVE_STACKTRACE
+#define init_stacktrace() {}
+#define print_stacktrace(A,B) {}
+#define safe_print_str(A,B,C) {}
+#endif /* HAVE_STACKTRACE */
+
+#ifndef HAVE_WRITE_CORE
+#define write_core(A) {}
+#endif
+
+#ifdef	__cplusplus
+}
+#endif