WL#3817: Simplify string / memory area types and make things more consistent (first part)

The following type conversions was done:

- Changed byte to uchar
- Changed gptr to uchar*
- Change my_string to char *
- Change my_size_t to size_t
- Change size_s to size_t

Removed declaration of byte, gptr, my_string, my_size_t and size_s. 

Following function parameter changes was done:
- All string functions in mysys/strings was changed to use size_t
  instead of uint for string lengths.
- All read()/write() functions changed to use size_t (including vio).
- All protocoll functions changed to use size_t instead of uint
- Functions that used a pointer to a string length was changed to use size_t*
- Changed malloc(), free() and related functions from using gptr to use void *
  as this requires fewer casts in the code and is more in line with how the
  standard functions work.
- Added extra length argument to dirname_part() to return the length of the
  created string.
- Changed (at least) following functions to take uchar* as argument:
  - db_dump()
  - my_net_write()
  - net_write_command()
  - net_store_data()
  - DBUG_DUMP()
  - decimal2bin() & bin2decimal()
- Changed my_compress() and my_uncompress() to use size_t. Changed one
  argument to my_uncompress() from a pointer to a value as we only return
  one value (makes function easier to use).
- Changed type of 'pack_data' argument to packfrm() to avoid casts.
- Changed in readfrm() and writefrom(), ha_discover and handler::discover()
  the type for argument 'frmdata' to uchar** to avoid casts.
- Changed most Field functions to use uchar* instead of char* (reduced a lot of
  casts).
- Changed field->val_xxx(xxx, new_ptr) to take const pointers.

Other changes:
- Removed a lot of not needed casts
- Added a few new cast required by other changes
- Added some cast to my_multi_malloc() arguments for safety (as string lengths
  needs to be uint, not size_t).
- Fixed all calls to hash-get-key functions to use size_t*. (Needed to be done
  explicitely as this conflict was often hided by casting the function to
  hash_get_key).
- Changed some buffers to memory regions to uchar* to avoid casts.
- Changed some string lengths from uint to size_t.
- Changed field->ptr to be uchar* instead of char*. This allowed us to
  get rid of a lot of casts.
- Some changes from true -> TRUE, false -> FALSE, unsigned char -> uchar
- Include zlib.h in some files as we needed declaration of crc32()
- Changed MY_FILE_ERROR to be (size_t) -1.
- Changed many variables to hold the result of my_read() / my_write() to be
  size_t. This was needed to properly detect errors (which are
  returned as (size_t) -1).
- Removed some very old VMS code
- Changed packfrm()/unpackfrm() to not be depending on uint size
  (portability fix)
- Removed windows specific code to restore cursor position as this
  causes slowdown on windows and we should not mix read() and pread()
  calls anyway as this is not thread safe. Updated function comment to
  reflect this. Changed function that depended on original behavior of
  my_pwrite() to itself restore the cursor position (one such case).
- Added some missing checking of return value of malloc().
- Changed definition of MOD_PAD_CHAR_TO_FULL_LENGTH to avoid 'long' overflow.
- Changed type of table_def::m_size from my_size_t to ulong to reflect that
  m_size is the number of elements in the array, not a string/memory
  length.
- Moved THD::max_row_length() to table.cc (as it's not depending on THD).
  Inlined max_row_length_blob() into this function.
- More function comments
- Fixed some compiler warnings when compiled without partitions.
- Removed setting of LEX_STRING() arguments in declaration (portability fix).
- Some trivial indentation/variable name changes.
- Some trivial code simplifications:
  - Replaced some calls to alloc_root + memcpy to use
    strmake_root()/strdup_root().
  - Changed some calls from memdup() to strmake() (Safety fix)
  - Simpler loops in client-simple.c

sql/protocol.cc

@@ -33,9 +33,9 @@ static void write_eof_packet(THD *thd, NET *net);
 #endif
 
 #ifndef EMBEDDED_LIBRARY
-bool Protocol::net_store_data(const char *from, uint length)
+bool Protocol::net_store_data(const uchar *from, size_t length)
 #else
-bool Protocol_binary::net_store_data(const char *from, uint length)
+bool Protocol_binary::net_store_data(const uchar *from, size_t length)
 #endif
 {
   ulong packet_length=packet->length();
@@ -46,10 +46,9 @@ bool Protocol_binary::net_store_data(const char *from, uint length)
   if (packet_length+9+length > packet->alloced_length() &&
       packet->realloc(packet_length+9+length))
     return 1;
-  char *to=(char*) net_store_length((char*) packet->ptr()+packet_length,
-				    length);
+  uchar *to= net_store_length((uchar*) packet->ptr()+packet_length, length);
   memcpy(to,from,length);
-  packet->length((uint) (to+length-packet->ptr()));
+  packet->length((uint) (to+length-(uchar*) packet->ptr()));
   return 0;
 }
 
@@ -227,7 +226,7 @@ net_printf_error(THD *thd, uint errcode, ...)
       memcpy(pos+3, mysql_errno_to_sqlstate(errcode), SQLSTATE_LENGTH);
     }
   }
-  VOID(net_real_write(net,(char*) net->buff,length+head_length+1+offset));
+  VOID(net_real_write(net, net->buff, length+head_length+1+offset));
 #else
   net->last_errno= errcode;
   strmake(net->last_error, text_pos, length);
@@ -271,7 +270,7 @@ void
 send_ok(THD *thd, ha_rows affected_rows, ulonglong id, const char *message)
 {
   NET *net= &thd->net;
-  char buff[MYSQL_ERRMSG_SIZE+10],*pos;
+  uchar buff[MYSQL_ERRMSG_SIZE+10],*pos;
   DBUG_ENTER("send_ok");
 
   if (net->no_send_ok || !net->vio)	// hack for re-parsing queries
@@ -307,8 +306,8 @@ send_ok(THD *thd, ha_rows affected_rows, ulonglong id, const char *message)
     pos+=2;
   }
   if (message)
-    pos=net_store_data((char*) pos, message, strlen(message));
-  VOID(my_net_write(net,buff,(uint) (pos-buff)));
+    pos= net_store_data(pos, (uchar*) message, strlen(message));
+  VOID(my_net_write(net, buff, (size_t) (pos-buff)));
   VOID(net_flush(net));
   /* We can't anymore send an error to the client */
   thd->net.report_error= 0;
@@ -318,7 +317,7 @@ send_ok(THD *thd, ha_rows affected_rows, ulonglong id, const char *message)
   DBUG_VOID_RETURN;
 }
 
-static char eof_buff[1]= { (char) 254 };        /* Marker for end of fields */
+static uchar eof_buff[1]= { (uchar) 254 };      /* Marker for end of fields */
 
 /*
   Send eof (= end of result set) to the client
@@ -383,7 +382,7 @@ static void write_eof_packet(THD *thd, NET *net)
     if (thd->is_fatal_error)
       thd->server_status&= ~SERVER_MORE_RESULTS_EXISTS;
     int2store(buff+3, thd->server_status);
-    VOID(my_net_write(net, (char*) buff, 5));
+    VOID(my_net_write(net, buff, 5));
   }
   else
     VOID(my_net_write(net, eof_buff, 1));
@@ -411,7 +410,7 @@ void net_send_error_packet(THD *thd, uint sql_errno, const char *err)
 {
   NET *net= &thd->net;
   uint length;
-  char buff[MYSQL_ERRMSG_SIZE+2], *pos;
+  uchar buff[MYSQL_ERRMSG_SIZE+2], *pos;
 
   DBUG_ENTER("send_error_packet");
 
@@ -433,17 +432,19 @@ void net_send_error_packet(THD *thd, uint sql_errno, const char *err)
     {
       /* The first # is to make the protocol backward compatible */
       buff[2]= '#';
-      pos= strmov(buff+3, mysql_errno_to_sqlstate(sql_errno));
+      pos= (uchar*) strmov((char*) buff+3, mysql_errno_to_sqlstate(sql_errno));
     }
-    length= (uint) (strmake(pos, err, MYSQL_ERRMSG_SIZE-1) - buff);
-    err=buff;
+    length= (uint) (strmake((char*) pos, err, MYSQL_ERRMSG_SIZE-1) -
+                    (char*) buff);
+    err= (char*) buff;
   }
   else
   {
     length=(uint) strlen(err);
     set_if_smaller(length,MYSQL_ERRMSG_SIZE-1);
   }
-  VOID(net_write_command(net,(uchar) 255, "", 0, (char*) err,length));
+  VOID(net_write_command(net,(uchar) 255, (uchar*) "", 0, (uchar*) err,
+                         length));
   DBUG_VOID_RETURN;
 }
 
@@ -459,17 +460,16 @@ void net_send_error_packet(THD *thd, uint sql_errno, const char *err)
   ulonglong for bigger numbers.
 */
 
-static char *net_store_length_fast(char *pkg, uint length)
+static uchar *net_store_length_fast(uchar *packet, uint length)
 {
-  uchar *packet=(uchar*) pkg;
   if (length < 251)
   {
     *packet=(uchar) length;
-    return (char*) packet+1;
+    return packet+1;
   }
   *packet++=252;
   int2store(packet,(uint) length);
-  return (char*) packet+2;
+  return packet+2;
 }
 
 
@@ -480,14 +480,14 @@ static char *net_store_length_fast(char *pkg, uint length)
 
 /* The following will only be used for short strings < 65K */
 
-char *net_store_data(char *to,const char *from, uint length)
+uchar *net_store_data(uchar *to, const uchar *from, size_t length)
 {
   to=net_store_length_fast(to,length);
   memcpy(to,from,length);
   return to+length;
 }
 
-char *net_store_data(char *to,int32 from)
+uchar *net_store_data(uchar *to,int32 from)
 {
   char buff[20];
   uint length=(uint) (int10_to_str(from,buff,10)-buff);
@@ -496,7 +496,7 @@ char *net_store_data(char *to,int32 from)
   return to+length;
 }
 
-char *net_store_data(char *to,longlong from)
+uchar *net_store_data(uchar *to,longlong from)
 {
   char buff[22];
   uint length=(uint) (longlong10_to_str(from,buff,10)-buff);
@@ -555,7 +555,7 @@ bool Protocol::send_fields(List<Item> *list, uint flags)
 {
   List_iterator_fast<Item> it(*list);
   Item *item;
-  char buff[80];
+  uchar buff[80];
   String tmp((char*) buff,sizeof(buff),&my_charset_bin);
   Protocol_text prot(thd);
   String *local_packet= prot.storage_packet();
@@ -564,8 +564,8 @@ bool Protocol::send_fields(List<Item> *list, uint flags)
 
   if (flags & SEND_NUM_ROWS)
   {				// Packet with number of elements
-    char *pos=net_store_length(buff, list->elements);
-    (void) my_net_write(&thd->net, buff,(uint) (pos-buff));
+    uchar *pos= net_store_length(buff, list->elements);
+    (void) my_net_write(&thd->net, buff, (size_t) (pos-buff));
   }
 
 #ifndef DBUG_OFF
@@ -698,7 +698,8 @@ err:
 bool Protocol::write()
 {
   DBUG_ENTER("Protocol::write");
-  DBUG_RETURN(my_net_write(&thd->net, packet->ptr(), packet->length()));
+  DBUG_RETURN(my_net_write(&thd->net, (uchar*) packet->ptr(),
+                           packet->length()));
 }
 #endif /* EMBEDDED_LIBRARY */
 
@@ -785,7 +786,7 @@ bool Protocol_text::store_null()
   and store in network buffer.
 */
 
-bool Protocol::store_string_aux(const char *from, uint length,
+bool Protocol::store_string_aux(const char *from, size_t length,
                                 CHARSET_INFO *fromcs, CHARSET_INFO *tocs)
 {
   /* 'tocs' is set 0 when client issues SET character_set_results=NULL */
@@ -794,15 +795,15 @@ bool Protocol::store_string_aux(const char *from, uint length,
       tocs != &my_charset_bin)
   {
     uint dummy_errors;
-    return convert->copy(from, length, fromcs, tocs, &dummy_errors) ||
-           net_store_data(convert->ptr(), convert->length());
+    return (convert->copy(from, length, fromcs, tocs, &dummy_errors) ||
+            net_store_data((uchar*) convert->ptr(), convert->length()));
   }
-  return net_store_data(from, length);
+  return net_store_data((uchar*) from, length);
 }
 
 
-bool Protocol_text::store(const char *from, uint length,
-			    CHARSET_INFO *fromcs, CHARSET_INFO *tocs)
+bool Protocol_text::store(const char *from, size_t length,
+                          CHARSET_INFO *fromcs, CHARSET_INFO *tocs)
 {
 #ifndef DBUG_OFF
   DBUG_ASSERT(field_types == 0 ||
@@ -817,7 +818,7 @@ bool Protocol_text::store(const char *from, uint length,
 }
 
 
-bool Protocol_text::store(const char *from, uint length,
+bool Protocol_text::store(const char *from, size_t length,
                           CHARSET_INFO *fromcs)
 {
   CHARSET_INFO *tocs= this->thd->variables.character_set_results;
@@ -841,8 +842,8 @@ bool Protocol_text::store_tiny(longlong from)
   field_pos++;
 #endif
   char buff[20];
-  return net_store_data((char*) buff,
-			(uint) (int10_to_str((int) from,buff, -10)-buff));
+  return net_store_data((uchar*) buff,
+			(size_t) (int10_to_str((int) from, buff, -10) - buff));
 }
 
 
@@ -855,8 +856,9 @@ bool Protocol_text::store_short(longlong from)
   field_pos++;
 #endif
   char buff[20];
-  return net_store_data((char*) buff,
-			(uint) (int10_to_str((int) from,buff, -10)-buff));
+  return net_store_data((uchar*) buff,
+			(size_t) (int10_to_str((int) from, buff, -10) -
+                                  buff));
 }
 
 
@@ -869,8 +871,9 @@ bool Protocol_text::store_long(longlong from)
   field_pos++;
 #endif
   char buff[20];
-  return net_store_data((char*) buff,
-			(uint) (int10_to_str((long int)from,buff, (from <0)?-10:10)-buff));
+  return net_store_data((uchar*) buff,
+			(size_t) (int10_to_str((long int)from, buff,
+                                               (from <0)?-10:10)-buff));
 }
 
 
@@ -882,10 +885,10 @@ bool Protocol_text::store_longlong(longlong from, bool unsigned_flag)
   field_pos++;
 #endif
   char buff[22];
-  return net_store_data((char*) buff,
-			(uint) (longlong10_to_str(from,buff,
-						  unsigned_flag ? 10 : -10)-
-				buff));
+  return net_store_data((uchar*) buff,
+			(size_t) (longlong10_to_str(from,buff,
+                                                    unsigned_flag ? 10 : -10)-
+                                  buff));
 }
 
 
@@ -899,7 +902,7 @@ bool Protocol_text::store_decimal(const my_decimal *d)
   char buff[DECIMAL_MAX_STR_LENGTH];
   String str(buff, sizeof(buff), &my_charset_bin);
   (void) my_decimal2string(E_DEC_FATAL_ERROR, d, 0, 0, 0, &str);
-  return net_store_data(str.ptr(), str.length());
+  return net_store_data((uchar*) str.ptr(), str.length());
 }
 
 
@@ -911,7 +914,7 @@ bool Protocol_text::store(float from, uint32 decimals, String *buffer)
   field_pos++;
 #endif
   buffer->set_real((double) from, decimals, thd->charset());
-  return net_store_data((char*) buffer->ptr(), buffer->length());
+  return net_store_data((uchar*) buffer->ptr(), buffer->length());
 }
 
 
@@ -923,7 +926,7 @@ bool Protocol_text::store(double from, uint32 decimals, String *buffer)
   field_pos++;
 #endif
   buffer->set_real(from, decimals, thd->charset());
-  return net_store_data((char*) buffer->ptr(), buffer->length());
+  return net_store_data((uchar*) buffer->ptr(), buffer->length());
 }
 
 
@@ -979,8 +982,9 @@ bool Protocol_text::store(MYSQL_TIME *tm)
 			   (int) tm->minute,
 			   (int) tm->second));
   if (tm->second_part)
-    length+= my_sprintf(buff+length,(buff+length, ".%06d", (int)tm->second_part));
-  return net_store_data((char*) buff, length);
+    length+= my_sprintf(buff+length,(buff+length, ".%06d",
+                                     (int)tm->second_part));
+  return net_store_data((uchar*) buff, length);
 }
 
 
@@ -992,8 +996,8 @@ bool Protocol_text::store_date(MYSQL_TIME *tm)
   field_pos++;
 #endif
   char buff[MAX_DATE_STRING_REP_LENGTH];
-  int length= my_date_to_str(tm, buff);
-  return net_store_data(buff, (uint) length);
+  size_t length= my_date_to_str(tm, buff);
+  return net_store_data((uchar*) buff, length);
 }
 
 
@@ -1020,7 +1024,7 @@ bool Protocol_text::store_time(MYSQL_TIME *tm)
 			   (int) tm->second));
   if (tm->second_part)
     length+= my_sprintf(buff+length,(buff+length, ".%06d", (int)tm->second_part));
-  return net_store_data((char*) buff, length);
+  return net_store_data((uchar*) buff, length);
 }
 
 
@@ -1057,12 +1061,12 @@ bool Protocol_binary::prepare_for_send(List<Item> *item_list)
 void Protocol_binary::prepare_for_resend()
 {
   packet->length(bit_fields+1);
-  bzero((char*) packet->ptr(), 1+bit_fields);
+  bzero((uchar*) packet->ptr(), 1+bit_fields);
   field_pos=0;
 }
 
 
-bool Protocol_binary::store(const char *from, uint length,
+bool Protocol_binary::store(const char *from, size_t length,
                             CHARSET_INFO *fromcs)
 {
   CHARSET_INFO *tocs= thd->variables.character_set_results;
@@ -1070,7 +1074,7 @@ bool Protocol_binary::store(const char *from, uint length,
   return store_string_aux(from, length, fromcs, tocs);
 }
 
-bool Protocol_binary::store(const char *from,uint length,
+bool Protocol_binary::store(const char *from, size_t length,
                             CHARSET_INFO *fromcs, CHARSET_INFO *tocs)
 {
   field_pos++;