Moved create/find/drop functions to a separate files (sp.cc,sp.h).

Fixed backpatching of forward jumps.
Implemented LOOP, WHILE, REPEAT (temporarily known as SPREPEAT).

Known bug: Expression evaluation still not quite ok (e.g. "x > 0"),
which is why IF and CASE is not yet implemented.


sql/Makefile.am:
  Added new sp.h/sp.cc file.
sql/item.h:
  New deferred result_type() method in Item_splocal.
sql/lex.h:
  Temporary fix until REPEAT conflict is solved. Use SPREPEAT for now.
sql/sp_head.cc:
  Moved create/find/drop functions to sp.cc.
  Fixed the backpatch stuff.
  (Also removed some dead code and updated comments.)
sql/sp_head.h:
  Moved create/find/drop declarations to sp.h.
  Fixed the backpatch stuff.
sql/sp_pcontext.h:
  New method: last_label().
sql/sql_parse.cc:
  Include sp.h.
sql/sql_yacc.yy:
  Fixed backpatching of forward jumps.
  Implemented LOOP, WHILE, and REPEAT. (Note: SPREPEAT for now.)

sql/Makefile.am

@@ -58,7 +58,7 @@ noinst_HEADERS =	item.h item_func.h item_sum.h item_cmpfunc.h \
 			log_event.h mini_client.h sql_repl.h slave.h \
 			stacktrace.h sql_sort.h sql_cache.h set_var.h \
 			spatial.h gstream.h sp_head.h sp_pcontext.h \
-			sp_rcontext.h
+			sp_rcontext.h sp.h
 mysqld_SOURCES =	sql_lex.cc sql_handler.cc \
 			item.cc item_sum.cc item_buff.cc item_func.cc \
 			item_cmpfunc.cc item_strfunc.cc item_timefunc.cc \
@@ -87,7 +87,7 @@ mysqld_SOURCES =	sql_lex.cc sql_handler.cc \
 			mini_client.cc mini_client_errors.c \
 			stacktrace.c repl_failsafe.h repl_failsafe.cc sql_olap.cc\
 			gstream.cc spatial.cc sql_help.cc \
-			sp_head.cc sp_pcontext.cc
+			sp_head.cc sp_pcontext.cc sp.cc
 gen_lex_hash_SOURCES =	gen_lex_hash.cc
 gen_lex_hash_LDADD =	$(LDADD) $(CXXLDFLAGS)
 

sql/item.h

@@ -126,6 +126,11 @@ class Item_splocal : public Item
     return m_offset;
   }
 
+  virtual Item_result result_type() const
+  {
+    return this_const_item()->result_type();
+  }
+
   // Abstract methods inherited from Item. Just defer the call to
   // the item in the frame
   inline enum Type type() const

sql/lex.h

@@ -317,10 +317,10 @@ static SYMBOL symbols[] = {
   { "REPAIR",		SYM(REPAIR),0,0},
   { "REPLACE",		SYM(REPLACE),0,0},
   { "REPLICATION",	SYM(REPLICATION),0,0},
+  { "SPREPEAT",		SYM(SPREPEAT_SYM),0,0}, /* QQ Temp. until conflict solved */
   { "REPEATABLE",	SYM(REPEATABLE_SYM),0,0},
   { "REQUIRE",	        SYM(REQUIRE_SYM),0,0},
   { "RESET",		SYM(RESET_SYM),0,0},
-  { "UNTIL",		SYM(UNTIL_SYM),0,0},
   { "USER_RESOURCES",	SYM(RESOURCES),0,0},
   { "RESTORE",		SYM(RESTORE_SYM),0,0},
   { "RESTRICT",		SYM(RESTRICT),0,0},
@@ -351,7 +351,7 @@ static SYMBOL symbols[] = {
   { "SONAME",		SYM(UDF_SONAME_SYM),0,0},
   { "SPATIAL",		SYM(SPATIAL_SYM),0,0},
   { "SPECIFIC",		SYM(SPECIFIC_SYM),0,0},
-  { "SPSET",		SYM(SPSET_SYM),0,0},
+  { "SPSET",		SYM(SPSET_SYM),0,0}, /* Temp. until SET parsing solved.  */
   { "SQL_BIG_RESULT",	SYM(SQL_BIG_RESULT),0,0},
   { "SQL_BUFFER_RESULT", SYM(SQL_BUFFER_RESULT),0,0},
   { "SQL_CACHE",        SYM(SQL_CACHE_SYM), 0, 0},
@@ -392,6 +392,7 @@ static SYMBOL symbols[] = {
   { "UNIQUE",		SYM(UNIQUE_SYM),0,0},
   { "UNLOCK",		SYM(UNLOCK_SYM),0,0},
   { "UNSIGNED",		SYM(UNSIGNED),0,0},
+  { "UNTIL",		SYM(UNTIL_SYM),0,0},
   { "USE",		SYM(USE_SYM),0,0},
   { "USE_FRM",		SYM(USE_FRM),0,0},
   { "USING",		SYM(USING),0,0},

sql/sp.cc

+/* Copyright (C) 2002 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 "mysql_priv.h"
+#include "sp.h"
+#include "sp_head.h"
+
+// Finds the SP 'name'. Currently this always reads from the database
+// and prepares (parse) it, but in the future it will first look in
+// the in-memory cache for SPs. (And store newly prepared SPs there of
+// course.)
+sp_head *
+sp_find(THD *thd, Item_string *iname)
+{
+  extern int yyparse(void *thd);
+  LEX *tmplex;
+  TABLE *table;
+  TABLE_LIST tables;
+  const char *defstr;
+  String *name;
+  sp_head *sp = NULL;
+
+  name = iname->const_string();
+  memset(&tables, 0, sizeof(tables));
+  tables.db= (char*)"mysql";
+  tables.real_name= tables.alias= (char*)"proc";
+  if (! (table= open_ltable(thd, &tables, TL_READ)))
+    return NULL;
+
+  if (table->file->index_read_idx(table->record[0], 0,
+				  (byte*)name->c_ptr(), name->length(),
+				  HA_READ_KEY_EXACT))
+    goto done;
+
+  if ((defstr= get_field(&thd->mem_root, table, 1)) == NULL)
+    goto done;
+
+  // QQ Set up our own mem_root here???
+  tmplex= lex_start(thd, (uchar*)defstr, strlen(defstr));
+  if (yyparse(thd) || thd->fatal_error || tmplex->sphead == NULL)
+    goto done;			// Error
+  else
+    sp = tmplex->sphead;
+
+ done:
+  if (table)
+    close_thread_tables(thd);
+  return sp;
+}
+
+int
+sp_create_procedure(THD *thd, char *name, uint namelen, char *def, uint deflen)
+{
+  int ret= 0;
+  TABLE *table;
+  TABLE_LIST tables;
+
+  memset(&tables, 0, sizeof(tables));
+  tables.db= (char*)"mysql";
+  tables.real_name= tables.alias= (char*)"proc";
+  /* Allow creation of procedures even if we can't open proc table */
+  if (! (table= open_ltable(thd, &tables, TL_WRITE)))
+  {
+    ret= -1;
+    goto done;
+  }
+
+  restore_record(table, 2);	// Get default values for fields
+
+  table->field[0]->store(name, namelen, default_charset_info);
+  table->field[1]->store(def, deflen, default_charset_info);
+
+  ret= table->file->write_row(table->record[0]);
+
+ done:
+  close_thread_tables(thd);
+  return ret;
+}
+
+int
+sp_drop(THD *thd, char *name, uint namelen)
+{
+  TABLE *table;
+  TABLE_LIST tables;
+
+  tables.db= (char *)"mysql";
+  tables.real_name= tables.alias= (char *)"proc";
+  if (! (table= open_ltable(thd, &tables, TL_WRITE)))
+    goto err;
+  if (! table->file->index_read_idx(table->record[0], 0,
+				    (byte *)name, namelen,
+				    HA_READ_KEY_EXACT))
+  {
+    int error;
+
+    if ((error= table->file->delete_row(table->record[0])))
+      table->file->print_error(error, MYF(0));
+  }
+  close_thread_tables(thd);
+  return 0;
+
+ err:
+  close_thread_tables(thd);
+  return -1;
+}

sql/sp.h

+/* -*- C++ -*- */
+/* Copyright (C) 2002 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 */
+
+#ifndef _SP_H_
+#define _SP_H_
+
+//
+// Finds a stored procedure given its name. Returns NULL if not found.
+//
+sp_head *
+sp_find(THD *thd, Item_string *name);
+
+int
+sp_create_procedure(THD *thd, char *name, uint namelen, char *def, uint deflen);
+
+int
+sp_drop(THD *thd, char *name, uint namelen);
+
+#endif /* _SP_H_ */

sql/sp_head.cc

@@ -20,6 +20,7 @@
 
 #include "mysql_priv.h"
 #include "sp_head.h"
+#include "sp.h"
 #include "sp_pcontext.h"
 #include "sp_rcontext.h"
 
@@ -31,9 +32,7 @@ eval_func_item(Item *it, enum enum_field_types type)
 {
   it= it->this_item();
 
-  /* QQ Which way do we do this? Or is there some even better way? */
-#if 1
-  /* QQ Obey the declared type of the variable */
+  /* QQ How do we do this? Is there some better way? */
   switch (type)
   {
   case MYSQL_TYPE_TINY:
@@ -77,30 +76,7 @@ eval_func_item(Item *it, enum enum_field_types type)
     /* QQ Don't know what to do with the rest. */
     break;
   }
-#else
-  /* QQ This looks simpler, but is wrong? It disregards the variable's type. */
-  switch (it->result_type())
-  {
-  case REAL_RESULT:
-    it= new Item_real(it->val());
-    break;
-  case INT_RESULT:
-    it= new Item_int(it->val_int());
-    break;
-  case STRING_RESULT:
-    {
-      char buffer[MAX_FIELD_WIDTH];
-      String tmp(buffer, sizeof(buffer), default_charset_info);
 
-      (void)it->val_str(&tmp);
-      it= new Item_string(buffer, sizeof(buffer), default_charset_info);
-      break;
-    }
-  default:
-    /* QQ Don't know what to do with the rest. */
-    break;
-  }
-#endif
   return it;
 }
 
@@ -113,6 +89,7 @@ sp_head::sp_head(LEX_STRING *name, LEX *lex)
   m_defstr= new Item_string(dstr, lex->end_of_query - lex->buf,
 			    default_charset_info);
   my_init_dynamic_array(&m_instr, sizeof(sp_instr *), 16, 8);
+  m_backpatch.empty();
 }
 
 int
@@ -144,7 +121,7 @@ sp_head::execute(THD *thd)
     Item *it = li++;		// Skip first one, it's the procedure name
 
     nctx = new sp_rcontext(csize);
-    // QQ: No error checking whatsoever right now
+    // QQ: No error checking whatsoever right now. Should do type checking?
     for (i = 0 ; (it= li++) && i < params ; i++)
     {
       sp_pvar_t *pvar = pctx->find_pvar(i);
@@ -168,7 +145,7 @@ sp_head::execute(THD *thd)
     // The rest of the frame are local variables which are all IN.
     // QQ We haven't found any hint of what the value is when unassigned,
     //    so we set it to NULL for now. It's an error to refer to an
-    //    unassigned variable (which should be detected by the parser).
+    //    unassigned variable anyway (which should be detected by the parser).
     for (; i < csize ; i++)
       nctx->push_item(NULL);
     thd->spcont= nctx;
@@ -212,6 +189,7 @@ sp_head::execute(THD *thd)
 }
 
 
+// Reset lex during parsing, before we parse a sub statement.
 void
 sp_head::reset_lex(THD *thd)
 {
@@ -244,6 +222,7 @@ sp_head::reset_lex(THD *thd)
   thd->lex.auxilliary_table_list.empty();
 }
 
+// Restore lex during parsing, after we have parsed a sub statement.
 void
 sp_head::restore_lex(THD *thd)
 {
@@ -255,123 +234,25 @@ sp_head::restore_lex(THD *thd)
 }
 
 void
-sp_head::push_backpatch(uint ip)
+sp_head::push_backpatch(sp_instr *i)
 {
-  (void)m_backpatch.push_front(&ip);
+  (void)m_backpatch.push_front(i);
 }
 
 void
-sp_head::backpatch(uint dest)
-{
-  while (! m_backpatch.is_empty())
-  {
-    uint *ip= m_backpatch.pop();
-    sp_instr_jump *i= static_cast<sp_instr_jump *>(get_instr(*ip));
-
-    i->set_destination(dest);
-  }
-}
-
-
-// ------------------------------------------------------------------
-
-// Finds the SP 'name'. Currently this always reads from the database
-// and prepares (parse) it, but in the future it will first look in
-// the in-memory cache for SPs. (And store newly prepared SPs there of
-// course.)
-sp_head *
-sp_find(THD *thd, Item_string *iname)
+sp_head::backpatch()
 {
-  extern int yyparse(void *thd);
-  LEX *tmplex;
-  TABLE *table;
-  TABLE_LIST tables;
-  const char *defstr;
-  String *name;
-  sp_head *sp = NULL;
-
-  name = iname->const_string();
-  memset(&tables, 0, sizeof(tables));
-  tables.db= (char*)"mysql";
-  tables.real_name= tables.alias= (char*)"proc";
-  if (! (table= open_ltable(thd, &tables, TL_READ)))
-    return NULL;
-
-  if (table->file->index_read_idx(table->record[0], 0,
-				  (byte*)name->c_ptr(), name->length(),
-				  HA_READ_KEY_EXACT))
-    goto done;
-
-  if ((defstr= get_field(&thd->mem_root, table, 1)) == NULL)
-    goto done;
-
-  // QQ Set up our own mem_root here???
-  tmplex= lex_start(thd, (uchar*)defstr, strlen(defstr));
-  if (yyparse(thd) || thd->fatal_error || tmplex->sphead == NULL)
-    goto done;			// Error
-  else
-    sp = tmplex->sphead;
-
- done:
-  if (table)
-    close_thread_tables(thd);
-  return sp;
-}
+  sp_instr *ip;
+  uint dest= instructions();
+  List_iterator_fast<sp_instr> li(m_backpatch);
 
-int
-sp_create_procedure(THD *thd, char *name, uint namelen, char *def, uint deflen)
-{
-  int ret= 0;
-  TABLE *table;
-  TABLE_LIST tables;
-
-  memset(&tables, 0, sizeof(tables));
-  tables.db= (char*)"mysql";
-  tables.real_name= tables.alias= (char*)"proc";
-  /* Allow creation of procedures even if we can't open proc table */
-  if (! (table= open_ltable(thd, &tables, TL_WRITE)))
+  while ((ip= li++))
   {
-    ret= -1;
-    goto done;
-  }
-
-  restore_record(table, 2);	// Get default values for fields
+    sp_instr_jump *i= static_cast<sp_instr_jump *>(ip);
 
-  table->field[0]->store(name, namelen, default_charset_info);
-  table->field[1]->store(def, deflen, default_charset_info);
-
-  ret= table->file->write_row(table->record[0]);
-
- done:
-  close_thread_tables(thd);
-  return ret;
-}
-
-int
-sp_drop(THD *thd, char *name, uint namelen)
-{
-  TABLE *table;
-  TABLE_LIST tables;
-
-  tables.db= (char *)"mysql";
-  tables.real_name= tables.alias= (char *)"proc";
-  if (! (table= open_ltable(thd, &tables, TL_WRITE)))
-    goto err;
-  if (! table->file->index_read_idx(table->record[0], 0,
-				    (byte *)name, namelen,
-				    HA_READ_KEY_EXACT))
-  {
-    int error;
-
-    if ((error= table->file->delete_row(table->record[0])))
-      table->file->print_error(error, MYF(0));
+    i->set_destination(dest);
   }
-  close_thread_tables(thd);
-  return 0;
-
- err:
-  close_thread_tables(thd);
-  return -1;
+  m_backpatch.empty();
 }
 
 
@@ -412,7 +293,6 @@ sp_instr_set::execute(THD *thd, uint *nextp)
 //
 // sp_instr_jump_if
 //
-
 int
 sp_instr_jump_if::execute(THD *thd, uint *nextp)
 {
@@ -428,7 +308,6 @@ sp_instr_jump_if::execute(THD *thd, uint *nextp)
 //
 // sp_instr_jump_if_not
 //
-
 int
 sp_instr_jump_if_not::execute(THD *thd, uint *nextp)
 {

sql/sp_head.h

@@ -73,10 +73,10 @@ class sp_head : public Sql_alloc
   restore_lex(THD *thd);
 
   void
-  push_backpatch(uint ip);
+  push_backpatch(sp_instr *i);
 
   void
-  backpatch(uint dest);
+  backpatch();
 
 private:
 
@@ -85,7 +85,7 @@ class sp_head : public Sql_alloc
   LEX *m_mylex;			// My own lex
   LEX m_lex;			// Temp. store for the other lex
   DYNAMIC_ARRAY m_instr;	// The "instructions"
-  List<uint> m_backpatch;	// Instructions needing backpaching
+  List<sp_instr> m_backpatch;	// Instructions needing backpaching
 
   inline sp_instr *
   get_instr(uint i)
@@ -99,20 +99,6 @@ class sp_head : public Sql_alloc
 }; // class sp_head : public Sql_alloc
 
 
-//
-// Find a stored procedure given its name. Returns NULL if not
-// found.
-//
-sp_head *
-sp_find(THD *thd, Item_string *name);
-
-int
-sp_create_procedure(THD *thd, char *name, uint namelen, char *def, uint deflen);
-
-int
-sp_drop(THD *thd, char *name, uint namelen);
-
-
 //
 // "Instructions"...
 //
@@ -243,7 +229,7 @@ class sp_instr_jump : public sp_instr
     m_dest= dest;
   }
 
-private:
+protected:
 
   int m_dest;			// Where we will go
 
@@ -272,7 +258,6 @@ class sp_instr_jump_if : public sp_instr_jump
 
 private:
 
-  int m_dest;			// Where we will go
   Item *m_expr;			// The condition
 
 }; // class sp_instr_jump_if : public sp_instr_jump
@@ -300,7 +285,6 @@ class sp_instr_jump_if_not : public sp_instr_jump
 
 private:
 
-  int m_dest;			// Where we will go
   Item *m_expr;			// The condition
 
 }; // class sp_instr_jump_if_not : public sp_instr_jump

sql/sp_pcontext.h

@@ -125,6 +125,12 @@ class sp_pcontext : public Sql_alloc
   sp_label_t *
   find_label(char *name);
 
+  inline sp_label_t *
+  last_label()
+  {
+    return m_label.head();
+  }
+
   inline void
   pop_label()
   {

sql/sql_parse.cc

@@ -28,6 +28,7 @@
 #endif
 
 #include "sp_head.h"
+#include "sp.h"
 
 #ifdef HAVE_OPENSSL
 /*

sql/sql_yacc.yy

@@ -531,6 +531,8 @@ bool my_yyoverflow(short **a, YYSTYPE **b,int *yystacksize);
 %token  ITERATE_SYM
 %token  LEAVE_SYM
 %token  LOOP_SYM
+/* QQ This is temporary, until the REPEAT conflict is solved. */
+%token  SPREPEAT_SYM
 %token  UNTIL_SYM
 %token  WHILE_SYM
 %token  ASENSITIVE_SYM
@@ -1053,8 +1055,10 @@ sp_proc_stmt:
 	  }
 	  sp_unlabeled_control
 	  {
-	    /* QQ backpatch here */
-	    Lex->spcont->pop_label();
+	    LEX *lex= Lex;
+
+	    lex->spcont->pop_label();
+	    lex->sphead->backpatch();
 	  }
 	| LEAVE_SYM IDENT
 	  {
@@ -1068,10 +1072,9 @@ sp_proc_stmt:
 	    }
 	    else
 	    {
-	      uint ip= lex->sphead->instructions();
-	      sp_instr_jump *i= new sp_instr_jump(ip, 0);
+	      sp_instr_jump *i= new sp_instr_jump(lex->sphead->instructions());
 
-	      lex->sphead->push_backpatch(ip);
+	      lex->sphead->push_backpatch(i);  /* Jumping forward */
               lex->sphead->add_instr(i);
 	    }
 	  }
@@ -1088,7 +1091,7 @@ sp_proc_stmt:
 	    else
 	    {
 	      uint ip= lex->sphead->instructions();
-	      sp_instr_jump *i= new sp_instr_jump(ip, lab->ip);
+	      sp_instr_jump *i= new sp_instr_jump(ip, lab->ip); /* Jump back */
 
               lex->sphead->add_instr(i);
 	    }
@@ -1148,29 +1151,59 @@ sp_labeled_control:
 	    }
 	    else
 	    {
-	      /* QQ backpatch here */
 	      lex->spcont->pop_label();
+	      lex->sphead->backpatch();
 	    }
 	  }
 	;
 
 sp_unlabeled_control:
-	  begin
+	  BEGIN_SYM
 	    sp_decls
 	    sp_proc_stmts
 	  END
-	  {
+	  { /* QQ This is just a dummy for grouping declarations and statements
+	       together. No [[NOT] ATOMIC] yet, and we need to figure out how
+	       make it coexist with the existing BEGIN COMMIT/ROLLBACK. */
 	    Lex->spcont->pop($2);
 	  }
 	| LOOP_SYM
-	    sp_proc_stmts
-	  END LOOP_SYM
+	  sp_proc_stmts END LOOP_SYM
+	  {
+	    LEX *lex= Lex;
+	    uint ip= lex->sphead->instructions();
+	    sp_label_t *lab= lex->spcont->last_label();  /* Jumping back */
+	    sp_instr_jump *i = new sp_instr_jump(ip, lab->ip);
+
+	    lex->sphead->add_instr(i);
+	  }
 	| WHILE_SYM expr DO_SYM
-	    sp_proc_stmts
-	  END WHILE_SYM
-	| FUNC_ARG2		/* "REPEAT" actually... */
-	    sp_proc_stmts
-	  UNTIL_SYM expr END FUNC_ARG2
+	  {
+	    LEX *lex= Lex;
+	    uint ip= lex->sphead->instructions();
+	    sp_instr_jump_if_not *i = new sp_instr_jump_if_not(ip, $2);
+
+	    lex->sphead->push_backpatch(i);  /* Jumping forward */
+            lex->sphead->add_instr(i);
+	  }
+	  sp_proc_stmts END WHILE_SYM
+	  {
+	    LEX *lex= Lex;
+	    uint ip= lex->sphead->instructions();
+	    sp_label_t *lab= lex->spcont->last_label();  /* Jumping back */
+	    sp_instr_jump *i = new sp_instr_jump(ip, lab->ip);
+
+	    lex->sphead->add_instr(i);
+	  }
+	| SPREPEAT_SYM sp_proc_stmts UNTIL_SYM expr END SPREPEAT_SYM
+	  { /* ^^ QQ temp. until conflict solved        ^^ */
+	    LEX *lex= Lex;
+	    uint ip= lex->sphead->instructions();
+	    sp_label_t *lab= lex->spcont->last_label();  /* Jumping back */
+	    sp_instr_jump_if_not *i = new sp_instr_jump_if_not(ip, $4, lab->ip);
+
+            lex->sphead->add_instr(i);
+	  }
 	;
 
 create2: