mysql flashback

本文转载自：http://mysql.taobao.org/images/0/0f/5.5.18_flashback.diff

Index: mysys/mf_iocache2.c
===================================================================
--- mysys/mf_iocache2.c	(revision 1)
+++ mysys/mf_iocache2.c	(working copy)
@@ -66,7 +66,45 @@
   DBUG_RETURN(0);
 }
 
+/* Flashback BY P.Linux */
+char *my_b_copy_to_string(IO_CACHE *cache, size_t *bytes_in_cache)
+{
+  char *buff;
+  char *tmp_buff;
+  size_t now_size;
+  size_t inc_size;
 
+  /* Reinit the cache to read from the beginning of the cache */
+  if (reinit_io_cache(cache, READ_CACHE, 0L, FALSE, FALSE))
+    return NULL;
+
+  now_size= my_b_bytes_in_cache(cache);
+  inc_size= 0;
+  buff= (char *) my_malloc(now_size + 1, MYF(0));
+  tmp_buff= buff;
+  do
+  {
+    now_size+= inc_size;
+    if(inc_size > 0)
+    {
+      buff= (char *) my_realloc(buff, now_size + 1, MYF(0));
+      tmp_buff= buff + (now_size - inc_size);
+      memcpy(tmp_buff, cache->read_pos, inc_size);
+    }
+    else
+    {
+      memcpy(tmp_buff, cache->read_pos, now_size);
+    }
+    cache->read_pos= cache->read_end;
+  } while ((inc_size= my_b_fill(cache)));
+  buff[now_size]= '\0';
+
+  reinit_io_cache(cache, WRITE_CACHE, 0, FALSE, TRUE);
+  *bytes_in_cache= now_size;
+  return buff;
+}
+/* End */
+
 my_off_t my_b_append_tell(IO_CACHE* info)
 {
   /*
Index: include/my_sys.h
===================================================================
--- include/my_sys.h	(revision 1)
+++ include/my_sys.h	(working copy)
@@ -534,6 +534,7 @@
 
 /* tell write offset in the SEQ_APPEND cache */
 int      my_b_copy_to_file(IO_CACHE *cache, FILE *file);
+char*    my_b_copy_to_string(IO_CACHE *cache, size_t *bytes_in_cache); // Flashback BY P.Linux
 my_off_t my_b_append_tell(IO_CACHE* info);
 my_off_t my_b_safe_tell(IO_CACHE* info); /* picks the correct tell() */
 
Index: sql/log_event.h
===================================================================
--- sql/log_event.h	(revision 1)
+++ sql/log_event.h	(working copy)
@@ -41,6 +41,10 @@
 #include "hash.h"
 #include "rpl_tblmap.h"
 #include "rpl_tblmap.cc"
+/* Flashback BY P.Linux */
+#include "sql_string.h"
+#include "sql_string.cc"
+/* End */
 #endif
 
 #ifdef MYSQL_SERVER
@@ -50,7 +54,9 @@
 #endif
 
 /* Forward declarations */
+#ifndef MYSQL_CLIENT
 class String;
+#endif
 
 #define PREFIX_SQL_LOAD "SQL_LOAD-"
 
@@ -1030,7 +1036,19 @@
   void print_base64(IO_CACHE* file, PRINT_EVENT_INFO* print_event_info,
                     bool is_more);
 #endif
+  /* Flashback BY P.Linux */
+  my_bool is_flashback;
+  String output_buf;
 
+  void free_output_buffer()
+  {
+    if (!output_buf.is_empty())
+    {
+      output_buf.free();
+    }
+  }
+  /* End */
+
   static void *operator new(size_t size)
   {
     return (void*) my_malloc((uint)size, MYF(MY_WME|MY_FAE));
@@ -1089,7 +1107,15 @@
   }
   Log_event(const char* buf, const Format_description_log_event
             *description_event);
-  virtual ~Log_event() { free_temp_buf();}
+  virtual ~Log_event() 
+  { 
+    free_temp_buf(); 
+    /* Flashback BY P.Linux */
+#ifdef MYSQL_CLIENT 
+    free_output_buffer(); 
+#endif
+    /* End */
+  } 
   void register_temp_buf(char* buf) { temp_buf = buf; }
   void free_temp_buf()
   {
@@ -3572,12 +3598,14 @@
 #ifdef MYSQL_CLIENT
   /* not for direct call, each derived has its own ::print() */
   virtual void print(FILE *file, PRINT_EVENT_INFO *print_event_info)= 0;
+  void exchange_update_rows(PRINT_EVENT_INFO *print_event_info, uchar *rows_buff); // Flashback BY P.Linux
   void print_verbose(IO_CACHE *file,
                      PRINT_EVENT_INFO *print_event_info);
   size_t print_verbose_one_row(IO_CACHE *file, table_def *td,
                                PRINT_EVENT_INFO *print_event_info,
                                MY_BITMAP *cols_bitmap,
-                               const uchar *ptr, const uchar *prefix);
+                               const uchar *ptr, const uchar *prefix,
+                               const my_bool only_parse= 0); // Flashback BY P.Linux
 #endif
 
 #ifdef MYSQL_SERVER
@@ -3658,6 +3686,8 @@
   uchar    *m_rows_cur;		/* One-after the end of the data */
   uchar    *m_rows_end;		/* One-after the end of the allocated space */
 
+  size_t   m_rows_before_size;  /* The length before m_rows_buf BY P.Linux */
+
   flag_set m_flags;		/* Flags for row-level events */
 
   /* helper functions */
@@ -4041,6 +4071,13 @@
   LEX_STRING m_message;
 };
 
+/* Flashback BY P.Linux */ 
+static inline char *copy_event_cache_to_string_and_reinit(IO_CACHE *cache, size_t *bytes_in_cache)
+{
+  return my_b_copy_to_string(cache, bytes_in_cache);
+}
+/* End */
+
 static inline bool copy_event_cache_to_file_and_reinit(IO_CACHE *cache,
                                                        FILE *file)
 {
Index: sql/log_event.cc
===================================================================
--- sql/log_event.cc	(revision 1)
+++ sql/log_event.cc	(working copy)
@@ -218,18 +218,30 @@
       constructor, but it would be possible to create a subclass
       holding the IO_CACHE itself.
    */
-  Write_on_release_cache(IO_CACHE *cache, FILE *file, flag_set flags = 0)
-    : m_cache(cache), m_file(file), m_flags(flags)
+  Write_on_release_cache(IO_CACHE *cache, FILE *file, flag_set flags = 0, Log_event *ev = NULL)
+    : m_cache(cache), m_file(file), m_flags(flags), m_ev(ev) // Flashback BY P.Linux
   {
     reinit_io_cache(m_cache, WRITE_CACHE, 0L, FALSE, TRUE);
   }
 
   ~Write_on_release_cache()
   {
+    if(m_ev == NULL)
+    {
     copy_event_cache_to_file_and_reinit(m_cache, m_file);
     if (m_flags | FLUSH_F)
       fflush(m_file);
   }
+    /* Flashback BY P.Linux */
+    else
+    {
+      size_t bytes_in_cache= 0;
+      char *buff= 0;
+      buff= copy_event_cache_to_string_and_reinit(m_cache, &bytes_in_cache);
+      m_ev->output_buf.append(buff, bytes_in_cache);
+    }
+    /* End */
+  }
 
   /*
     Return a pointer to the internal IO_CACHE.
@@ -258,6 +270,7 @@
   IO_CACHE *m_cache;
   FILE *m_file;
   flag_set m_flags;
+  Log_event *m_ev; // Flashback BY P.Linux
 };
 
 #ifndef DBUG_OFF
@@ -1860,7 +1873,184 @@
   return 0;
 }
 
+/* Flashback By P.Linux */
+static size_t
+log_event_print_value(const uchar *ptr,
+                      uint type, uint meta,
+                      char *typestr, size_t typestr_length)
+{
+  uint32 length= 0;
 
+  if (type == MYSQL_TYPE_STRING)
+  {
+    if (meta >= 256)
+    {
+      uint byte0= meta >> 8;
+      uint byte1= meta & 0xFF;
+      
+      if ((byte0 & 0x30) != 0x30)
+      {
+        /* a long CHAR() field: see #37426 */
+        length= byte1 | (((byte0 & 0x30) ^ 0x30) << 4);
+        type= byte0 | 0x30;
+      }
+      else
+        length = meta & 0xFF;
+    }
+    else
+      length= meta;
+  }
+
+  switch (type) {
+  case MYSQL_TYPE_LONG:
+    {
+      return 4;
+    }
+
+  case MYSQL_TYPE_TINY:
+    {
+      return 1;
+    }
+
+  case MYSQL_TYPE_SHORT:
+    {
+      return 2;
+    }
+  
+  case MYSQL_TYPE_INT24:
+    {
+      return 3;
+    }
+
+  case MYSQL_TYPE_LONGLONG:
+    {
+      return 8;
+    }
+
+  case MYSQL_TYPE_NEWDECIMAL:
+    {
+      uint precision= meta >> 8;
+      uint decimals= meta & 0xFF;
+      uint bin_size= my_decimal_get_binary_size(precision, decimals);
+      return bin_size;
+    }
+
+  case MYSQL_TYPE_FLOAT:
+    {
+      return 4;
+    }
+
+  case MYSQL_TYPE_DOUBLE:
+    {
+      return 8;
+    }
+  
+  case MYSQL_TYPE_BIT:
+    {
+      /* Meta-data: bit_len, bytes_in_rec, 2 bytes */
+      uint nbits= ((meta >> 8) * 8) + (meta & 0xFF);
+      length= (nbits + 7) / 8;
+      return length;
+    }
+
+  case MYSQL_TYPE_TIMESTAMP:
+    {
+      return 4;
+    }
+
+  case MYSQL_TYPE_DATETIME:
+    {
+      return 8;
+    }
+
+  case MYSQL_TYPE_TIME:
+    {
+      return 3;
+    }
+    
+  case MYSQL_TYPE_NEWDATE:
+    {
+      return 3;
+    }
+    
+  case MYSQL_TYPE_DATE:
+    {
+      return 3;
+    }
+  
+  case MYSQL_TYPE_YEAR:
+    {
+      return 1;
+    }
+  
+  case MYSQL_TYPE_ENUM:
+    switch (meta & 0xFF) {
+    case 1:
+      return 1;
+    case 2:
+      {
+        return 2;
+      }
+    default:
+      return 0;
+    }
+    break;
+    
+  case MYSQL_TYPE_SET:
+    return meta & 0xFF;
+  
+  case MYSQL_TYPE_BLOB:
+    switch (meta) {
+    case 1:
+      length= *ptr;
+      return length + 1;
+    case 2:
+      length= uint2korr(ptr);
+      return length + 2;
+    case 3:
+      length= uint3korr(ptr);
+      return length + 3;
+    case 4:
+      length= uint4korr(ptr);
+      return length + 4;
+    default:
+      return 0;
+    }
+
+  case MYSQL_TYPE_VARCHAR:
+  case MYSQL_TYPE_VAR_STRING:
+    length= meta;
+    if (length < 256)
+    {
+      length= *ptr;
+      return length + 1;
+    }
+    else
+    {
+      length= uint2korr(ptr);
+      return length + 2;
+    }
+
+  case MYSQL_TYPE_STRING:
+    if (length < 256)
+    {
+      length= *ptr;
+      return length + 1;
+    }
+    else
+    {
+      length= uint2korr(ptr);
+      return length + 2;
+    }
+
+    break;
+  }
+  *typestr= 0;
+  return 0;
+}
+
+/* End */
+
 /**
   Print a packed row into IO cache
   
@@ -1879,7 +2069,8 @@
 Rows_log_event::print_verbose_one_row(IO_CACHE *file, table_def *td,
                                       PRINT_EVENT_INFO *print_event_info,
                                       MY_BITMAP *cols_bitmap,
-                                      const uchar *value, const uchar *prefix)
+                                      const uchar *value, const uchar *prefix,
+                                      const my_bool only_parse) // Flashback BY P.Linux
 {
   const uchar *value0= value;
   const uchar *null_bits= value;
@@ -1888,6 +2079,7 @@
   
   value+= (m_width + 7) / 8;
   
+  if (!only_parse) // Flashback BY P.Linux
   my_b_printf(file, "%s", prefix);
   
   for (size_t i= 0; i < td->size(); i ++)
@@ -1900,14 +2092,27 @@
     
     if (is_null)
     {
+      if (!only_parse) // Flashback BY P.Linux
       my_b_printf(file, "###   @%d=NULL", i + 1);
     }
     else
     {
+      size_t size= 0; // Flashback BY P.Linux
+      if (!only_parse) 
+      {
       my_b_printf(file, "###   @%d=", i + 1);
-      size_t size= log_event_print_value(file, value,
+        size= log_event_print_value(file, value,
+                                    td->type(i), td->field_metadata(i),
+                                    typestr, sizeof(typestr));
+      }
+      /* Flashback BY P.Linux */
+      else
+      {
+        size= log_event_print_value(value,
                                          td->type(i), td->field_metadata(i),
                                          typestr, sizeof(typestr));
+      }
+      /* End */
       if (!size)
         return 0;
 
@@ -1916,8 +2121,11 @@
 
     if (print_event_info->verbose > 1)
     {
+      if (!only_parse) // Flashback BY P.Linux
       my_b_printf(file, " /* ");
 
+      if (!only_parse) // Flashback BY P.Linux
+      {
       if (typestr[0])
         my_b_printf(file, "%s ", typestr);
       else
@@ -1928,7 +2136,9 @@
                   td->maybe_null(i), is_null);
       my_b_printf(file, "*/");
     }
+    }
     
+    if (!only_parse) // Flashback BY P.Linux
     my_b_printf(file, "\n");
     
     null_bit_index++;
@@ -1936,7 +2146,57 @@
   return value - value0;
 }
 
+/* Flashback BY P.Linux */
+void Rows_log_event::exchange_update_rows(PRINT_EVENT_INFO *print_event_info,
+                                          uchar *rows_buff)
+{
+  Table_map_log_event *map;
+  table_def *td;
+  uchar *data_buff= rows_buff + m_rows_before_size;
 
+  if (!(map= print_event_info->m_table_map.get_table(m_table_id)) ||
+      !(td= map->create_table_def()))
+  {
+    return;
+  }
+
+  for (uchar *value= m_rows_buf; value < m_rows_end; )
+  {
+    uchar *start_pos= value;
+    size_t length1;
+    if (!(length1= print_verbose_one_row(NULL, td, print_event_info,
+                                         &m_cols, value,
+                                         (const uchar*) "", TRUE)))
+      return;
+    value+= length1;
+
+    size_t length2;
+    if (!(length2= print_verbose_one_row(NULL, td, print_event_info,
+                                        &m_cols, value,
+                                        (const uchar*) "", TRUE)))
+      return;
+    value+= length2;
+
+    /* Swap SET and WHERE part */
+    uchar *swap_buff1= (uchar *) my_malloc(length1, MYF(0));
+    uchar *swap_buff2= (uchar *) my_malloc(length2, MYF(0));
+
+    memcpy(swap_buff1, start_pos, length1); // SET part
+    memcpy(swap_buff2, start_pos + length1, length2); // WHERE part
+
+    memcpy(start_pos, swap_buff2, length2);
+    memcpy(start_pos + length2, swap_buff1, length1);
+
+    /* Free Swap Buffer */
+    my_free(swap_buff1);
+    my_free(swap_buff2);
+  }
+
+  /* Move to rows_buff */
+  memcpy(data_buff, m_rows_buf, m_rows_end - m_rows_buf);
+}
+/* End */
+
 /**
   Print a row event into IO cache in human readable form (in SQL format)
   
@@ -2018,7 +2278,7 @@
                              PRINT_EVENT_INFO* print_event_info,
                              bool more)
 {
-  const uchar *ptr= (const uchar *)temp_buf;
+  uchar *ptr= (uchar *)temp_buf;
   uint32 size= uint4korr(ptr + EVENT_LEN_OFFSET);
   DBUG_ENTER("Log_event::print_base64");
 
@@ -2030,6 +2290,26 @@
     DBUG_VOID_RETURN;
   }
 
+  /* Flashback BY P.Linux */
+  if(is_flashback)
+  {
+    switch (ptr[4]) {
+      case WRITE_ROWS_EVENT:
+        ptr[4]= DELETE_ROWS_EVENT;
+        break;
+      case DELETE_ROWS_EVENT:
+        ptr[4]= WRITE_ROWS_EVENT;
+        break;
+      case UPDATE_ROWS_EVENT:
+        Rows_log_event *ev= NULL;
+        ev= new Update_rows_log_event((const char*) ptr, size,
+                                       glob_description_event);
+        ev->exchange_update_rows(print_event_info, ptr);
+        break;
+    }
+  }
+  /* End */
+
   if (base64_encode(ptr, (size_t) size, tmp_str))
   {
     DBUG_ASSERT(0);
@@ -3146,7 +3426,7 @@
 
 void Query_log_event::print(FILE* file, PRINT_EVENT_INFO* print_event_info)
 {
-  Write_on_release_cache cache(&print_event_info->head_cache, file);
+  Write_on_release_cache cache(&print_event_info->head_cache, file, 0, this);
 
   print_query_header(&cache, print_event_info);
   my_b_write(&cache, (uchar*) query, q_len);
@@ -5571,7 +5851,7 @@
 void Xid_log_event::print(FILE* file, PRINT_EVENT_INFO* print_event_info)
 {
   Write_on_release_cache cache(&print_event_info->head_cache, file,
-                               Write_on_release_cache::FLUSH_F);
+                               Write_on_release_cache::FLUSH_F, this); // Flashback BY P.Linux
 
   if (!print_event_info->short_form)
   {
@@ -7451,6 +7731,7 @@
     m_rows_end= m_rows_buf + data_size;
     m_rows_cur= m_rows_end;
     memcpy(m_rows_buf, ptr_rows_data, data_size);
+    m_rows_before_size= ptr_rows_data - (const uchar *) buf; // Flashback BY P.Linux
   }
   else
     m_cols.bitmap= 0; // to not free it
@@ -8109,8 +8390,16 @@
 
   if (get_flags(STMT_END_F))
   {
-    copy_event_cache_to_file_and_reinit(head, file);
-    copy_event_cache_to_file_and_reinit(body, file);
+    /* Flashback BY P.Linux */
+    size_t bytes_in_cache= 0;
+    char *buff= 0;
+
+    buff= copy_event_cache_to_string_and_reinit(head, &bytes_in_cache);
+    output_buf.append(buff, bytes_in_cache);
+
+    buff= copy_event_cache_to_string_and_reinit(body, &bytes_in_cache);
+    output_buf.append(buff, bytes_in_cache);
+    /* End */
   }
 }
 #endif
Index: client/mysqlbinlog.cc
===================================================================
--- client/mysqlbinlog.cc	(revision 1)
+++ client/mysqlbinlog.cc	(working copy)
@@ -44,6 +44,11 @@
 
 #define CLIENT_CAPABILITIES	(CLIENT_LONG_PASSWORD | CLIENT_LONG_FLAG | CLIENT_LOCAL_FILES)
 
+
+/* Flashback BY P.Linux */
+DYNAMIC_ARRAY binlog_events;
+/* End */
+
 char server_version[SERVER_VERSION_LENGTH];
 ulong server_id = 0;
 
@@ -103,6 +108,8 @@
 static MYSQL* mysql = NULL;
 static char* dirname_for_local_load= 0;
 
+static my_bool flashback_opt; // Flashback BY P.Linux
+
 /**
   Pointer to the Format_description_log_event of the currently active binlog.
 
@@ -699,6 +706,8 @@
   print_event_info->short_form= short_form;
   Exit_status retval= OK_CONTINUE;
 
+
+  ev->is_flashback= flashback_opt; // Flashback BY P.Linux
   /*
     Format events are not concerned by --offset and such, we always need to
     read them to be able to process the wanted events.
@@ -736,8 +745,11 @@
       goto end;
     }
     if (!short_form)
+    {
       fprintf(result_file, "# at %s\n",llstr(pos,ll_buff));
 
+    }
+
     if (!opt_hexdump)
       print_event_info->hexdump_from= 0; /* Disabled */
     else
@@ -1003,6 +1015,17 @@
   */
   if (ev)
   {
+    /* Flashback BY P.Linux */
+    if(!ev->output_buf.is_empty())
+    {
+      String *tmp_str= new String[1];
+      tmp_str->copy(ev->output_buf);
+      (void) push_dynamic(&binlog_events, (uchar *) tmp_str);
+      if (!flashback_opt)
+        printf("%s", ev->output_buf.ptr());
+      ev->free_output_buffer();
+    }
+    /* End */
     if (remote_opt)
       ev->temp_buf= 0;
     if (destroy_evt) /* destroy it later if not set (ignored table map) */
@@ -1098,6 +1121,11 @@
   {"read-from-remote-server", 'R', "Read binary logs from a MySQL server.",
    &remote_opt, &remote_opt, 0, GET_BOOL, NO_ARG, 0, 0, 0, 0,
    0, 0},
+  /* Flashback BY P.Linux */
+  {"flashback", 'B', "Flashback data to start_postition or start_datetime.",
+   &flashback_opt, &flashback_opt, 0, GET_BOOL, NO_ARG, 0, 0, 0, 0,
+   0, 0},
+  /* End */
   {"result-file", 'r', "Direct output to a given file.", 0, 0, 0, GET_STR,
    REQUIRED_ARG, 0, 0, 0, 0, 0, 0},
   {"server-id", OPT_SERVER_ID,
@@ -1330,6 +1358,11 @@
   case 'R':
     remote_opt= 1;
     break;
+  /* Flashback BY P.Linux */
+  case 'B':
+    flashback_opt= 1;
+    break;
+  /* End */
   case OPT_MYSQL_PROTOCOL:
     opt_protocol= find_type_or_exit(argument, &sql_protocol_typelib,
                                     opt->name);
@@ -2034,6 +2067,10 @@
   DBUG_ENTER("main");
   DBUG_PROCESS(argv[0]);
 
+  /* Flashback BY P.Linux*/
+  (void) my_init_dynamic_array(&binlog_events, sizeof(String), 1024, 1024); 
+  /* End */
+
   my_init_time(); // for time functions
 
   if (load_defaults("my", load_default_groups, &argc, &argv))
@@ -2111,6 +2148,21 @@
     start_position= BIN_LOG_HEADER_SIZE;
   }
 
+  /* Flashback BY P.Linux */
+  if(flashback_opt)
+  {
+    uint i= 0;
+    for (i=  binlog_events.elements - 1; i > 0; --i)
+    {
+      String *event_str= dynamic_element(&binlog_events, i, String*); 
+      printf("%s", event_str->ptr());
+    }
+    delete_dynamic(&binlog_events);
+    /* Set delimiter back to semicolon */
+    fprintf(result_file, "DELIMITER ;\n");
+  }
+  /* End */
+
   /*
     Issue a ROLLBACK in case the last printed binlog was crashed and had half
     of transaction.

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