Commit c038b644 authored by unknown's avatar unknown
Browse files

plugin versioning: we cannot assume that sizeof(st_mysql_plugin) 

is the same in the plugin and in the mysqld.
store the size in the plugin.

To simplify access to plugin's st_mysql_plugin, copy it on open and
convert to the latest version, so that the rest of the code would
not need to care about versions.


include/plugin.h:
  plugin versioning: we cannot assume that sizeof(st_mysql_plugin)
  is the same in the plugin and in the mysqld.
  store the size in the plugin.
parent bb1e8bd5

include/plugin.h

+1 −0
Original line number Diff line number Diff line
@@ -39,6 +39,7 @@ 


#define mysql_declare_plugin                                          \

int _mysql_plugin_interface_version_= MYSQL_PLUGIN_INTERFACE_VERSION; \

int _mysql_sizeof_struct_st_plugin_= sizeof(struct st_mysql_plugin); \

struct st_mysql_plugin _mysql_plugin_declarations_[]= {

#define mysql_declare_plugin_end ,{0,0,0,0,0,0,0}}

sql/sql_plugin.cc

+82 −10
Original line number Diff line number Diff line
@@ -29,6 +29,8 @@ LEX_STRING plugin_type_names[]= 
};

static const char *plugin_interface_version_sym=

                   "_mysql_plugin_interface_version_";

static const char *sizeof_st_plugin_sym=

                   "_mysql_sizeof_struct_st_plugin_";

static const char *plugin_declarations_sym= "_mysql_plugin_declarations_";

static int min_plugin_interface_version= 0x0000;

/* Note that 'int version' must be the first field of every plugin
@@ -90,6 +92,13 @@ static st_plugin_dl *plugin_dl_insert_or_reuse(struct st_plugin_dl *plugin_dl) 
                              struct st_plugin_dl *));

}



static inline void free_plugin_mem(struct st_plugin_dl *p)

{

  dlclose(p->handle);

  my_free(p->dl.str, MYF(MY_ALLOW_ZERO_PTR));

  if (p->version != MYSQL_PLUGIN_INTERFACE_VERSION)

    my_free((gptr)p->plugins, MYF(MY_ALLOW_ZERO_PTR));

}



static st_plugin_dl *plugin_dl_add(LEX_STRING *dl, int report)

{
@@ -121,6 +130,7 @@ static st_plugin_dl *plugin_dl_add(LEX_STRING *dl, int report) 
    tmp->ref_count++;

    DBUG_RETURN(tmp);

  }

  bzero(&plugin_dl, sizeof(plugin_dl));

  /* Compile dll path */

  strxnmov(dlpath, sizeof(dlpath) - 1, opt_plugin_dir, "/", dl->str, NullS);

  plugin_dl.ref_count= 1;
@@ -136,7 +146,7 @@ static st_plugin_dl *plugin_dl_add(LEX_STRING *dl, int report) 
  /* Determine interface version */

  if (!(sym= dlsym(plugin_dl.handle, plugin_interface_version_sym)))

  {

    dlclose(plugin_dl.handle);

    free_plugin_mem(&plugin_dl);

    if (report & REPORT_TO_USER)

      my_error(ER_CANT_FIND_DL_ENTRY, MYF(0), plugin_interface_version_sym);

    if (report & REPORT_TO_LOG)
@@ -148,7 +158,7 @@ static st_plugin_dl *plugin_dl_add(LEX_STRING *dl, int report) 
  if (plugin_dl.version < min_plugin_interface_version ||

      (plugin_dl.version >> 8) > (MYSQL_PLUGIN_INTERFACE_VERSION >> 8))

  {

    dlclose(plugin_dl.handle);

    free_plugin_mem(&plugin_dl);

    if (report & REPORT_TO_USER)

      my_error(ER_CANT_OPEN_LIBRARY, MYF(0), dlpath, 0,

               "plugin interface version mismatch");
@@ -160,19 +170,84 @@ static st_plugin_dl *plugin_dl_add(LEX_STRING *dl, int report) 
  /* Find plugin declarations */

  if (!(sym= dlsym(plugin_dl.handle, plugin_declarations_sym)))

  {

    dlclose(plugin_dl.handle);

    free_plugin_mem(&plugin_dl);

    if (report & REPORT_TO_USER)

      my_error(ER_CANT_FIND_DL_ENTRY, MYF(0), plugin_declarations_sym);

    if (report & REPORT_TO_LOG)

      sql_print_error(ER(ER_CANT_FIND_DL_ENTRY), plugin_declarations_sym);

    DBUG_RETURN(0);

  }



  if (plugin_dl.version != MYSQL_PLUGIN_INTERFACE_VERSION)

  {

    int i, sizeof_st_plugin;

    struct st_mysql_plugin *old, *cur;

    char *ptr=(char *)sym;



    if ((sym= dlsym(plugin_dl.handle, sizeof_st_plugin_sym)))

      sizeof_st_plugin= *(int *)sym;

    else

    {

#ifdef ERROR_ON_NO_SIZEOF_PLUGIN_SYMBOL

      free_plugin_mem(&plugin_dl);

      if (report & REPORT_TO_USER)

        my_error(ER_CANT_FIND_DL_ENTRY, MYF(0), sizeof_st_plugin_sym);

      if (report & REPORT_TO_LOG)

        sql_print_error(ER(ER_CANT_FIND_DL_ENTRY), sizeof_st_plugin_sym);

      DBUG_RETURN(0);

#else

      DBUG_ASSERT(min_plugin_interface_version == 0);

      sizeof_st_plugin=(int)offsetof(struct st_mysql_plugin, version);

#endif

    }



    for (i= 0;

         ((struct st_mysql_plugin *)(ptr+i*sizeof_st_plugin))->info;

         i++)

      /* no op */;



    cur= (struct st_mysql_plugin*)

          my_malloc(i*sizeof(struct st_mysql_plugin), MYF(MY_ZEROFILL|MY_WME));

    if (!cur)

    {

      free_plugin_mem(&plugin_dl);

      if (report & REPORT_TO_USER)

        my_error(ER_OUTOFMEMORY, MYF(0), plugin_dl.dl.length);

      if (report & REPORT_TO_LOG)

        sql_print_error(ER(ER_OUTOFMEMORY), plugin_dl.dl.length);

      DBUG_RETURN(0);

    }

    for (i=0;

         (old=(struct st_mysql_plugin *)(ptr+i*sizeof_st_plugin))->info;

         i++)

    {

      switch (plugin_dl.version) {

      default: /* version > MYSQL_PLUGIN_INTERFACE_VERSION */

        /* fall through */

      case 0x0001:

        cur[i].version=old->version;

        // cur[i].status_vars=old->status_vars;

        /* fall through */

      case 0x0000:

        cur[i].type=old->type;

        cur[i].info=old->info;

        cur[i].name=old->name;

        cur[i].author=old->author;

        cur[i].descr=old->descr;

        cur[i].init=old->init;

        cur[i].deinit=old->deinit;

      }

    }



    sym=cur;

  }

  plugin_dl.plugins= (struct st_mysql_plugin *)sym;



  /* Duplicate and convert dll name */

  plugin_dl.dl.length= dl->length * files_charset_info->mbmaxlen + 1;

  if (! (plugin_dl.dl.str= my_malloc(plugin_dl.dl.length, MYF(0))))

  {

    dlclose(plugin_dl.handle);

    free_plugin_mem(&plugin_dl);

    if (report & REPORT_TO_USER)

      my_error(ER_OUTOFMEMORY, MYF(0), plugin_dl.dl.length);

    if (report & REPORT_TO_LOG)
@@ -186,8 +261,7 @@ static st_plugin_dl *plugin_dl_add(LEX_STRING *dl, int report) 
  /* Add this dll to array */

  if (! (tmp= plugin_dl_insert_or_reuse(&plugin_dl)))

  {

    dlclose(plugin_dl.handle);

    my_free(plugin_dl.dl.str, MYF(0));

    free_plugin_mem(&plugin_dl);

    if (report & REPORT_TO_USER)

      my_error(ER_OUTOFMEMORY, MYF(0), sizeof(struct st_plugin_dl));

    if (report & REPORT_TO_LOG)
@@ -223,8 +297,7 @@ static void plugin_dl_del(LEX_STRING *dl) 
      /* Do not remove this element, unless no other plugin uses this dll. */

      if (! --tmp->ref_count)

      {

        dlclose(tmp->handle);

        my_free(tmp->dl.str, MYF(0));

        free_plugin_mem(tmp);

        bzero(tmp, sizeof(struct st_plugin_dl));

      }

      break;
@@ -646,8 +719,7 @@ void plugin_free(void) 
#ifdef HAVE_DLOPEN

    if (tmp->handle)

    {

      dlclose(tmp->handle);

      my_free(tmp->dl.str, MYF(0));

      free_plugin_mem(tmp);

    }

#endif

  }