summaryrefslogtreecommitdiffstats
path: root/storage/csv
diff options
context:
space:
mode:
authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-13 12:24:36 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-13 12:24:36 +0000
commit06eaf7232e9a920468c0f8d74dcf2fe8b555501c (patch)
treee2c7b5777f728320e5b5542b6213fd3591ba51e2 /storage/csv
parentInitial commit. (diff)
downloadmariadb-06eaf7232e9a920468c0f8d74dcf2fe8b555501c.tar.xz
mariadb-06eaf7232e9a920468c0f8d74dcf2fe8b555501c.zip
Adding upstream version 1:10.11.6.upstream/1%10.11.6
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'storage/csv')
-rw-r--r--storage/csv/CMakeLists.txt17
-rw-r--r--storage/csv/ha_tina.cc1837
-rw-r--r--storage/csv/ha_tina.h180
-rw-r--r--storage/csv/transparent_file.cc109
-rw-r--r--storage/csv/transparent_file.h43
5 files changed, 2186 insertions, 0 deletions
diff --git a/storage/csv/CMakeLists.txt b/storage/csv/CMakeLists.txt
new file mode 100644
index 00000000..3131ebd4
--- /dev/null
+++ b/storage/csv/CMakeLists.txt
@@ -0,0 +1,17 @@
+# Copyright (c) 2006, 2010, Oracle and/or its affiliates. All rights reserved.
+#
+# 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; version 2 of the License.
+#
+# 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., 51 Franklin St, Fifth Floor, Boston, MA 02110-1335 USA
+
+SET(CSV_SOURCES ha_tina.cc ha_tina.h transparent_file.cc transparent_file.h)
+MYSQL_ADD_PLUGIN(csv ${CSV_SOURCES} STORAGE_ENGINE MANDATORY)
diff --git a/storage/csv/ha_tina.cc b/storage/csv/ha_tina.cc
new file mode 100644
index 00000000..e705ff0e
--- /dev/null
+++ b/storage/csv/ha_tina.cc
@@ -0,0 +1,1837 @@
+/* Copyright (c) 2004, 2011, Oracle and/or its affiliates.
+
+ 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; version 2 of the License.
+
+ 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., 51 Franklin St, Fifth Floor, Boston, MA 02110-1335 USA */
+
+/*
+ Make sure to look at ha_tina.h for more details.
+
+ First off, this is a play thing for me, there are a number of things
+ wrong with it:
+ *) It was designed for csv and therefore its performance is highly
+ questionable.
+ *) Indexes have not been implemented. This is because the files can
+ be traded in and out of the table directory without having to worry
+ about rebuilding anything.
+ *) NULLs and "" are treated equally (like a spreadsheet).
+ *) There was in the beginning no point to anyone seeing this other
+ then me, so there is a good chance that I haven't quite documented
+ it well.
+ *) Less design, more "make it work"
+
+ Now there are a few cool things with it:
+ *) Errors can result in corrupted data files.
+ *) Data files can be read by spreadsheets directly.
+
+TODO:
+ *) Move to a block system for larger files
+ *) Error recovery, its all there, just need to finish it
+ *) Document how the chains work.
+
+ -Brian
+*/
+
+#include <my_global.h>
+#include "sql_priv.h"
+#include "sql_class.h" // SSV
+#include <mysql/psi/mysql_file.h>
+#include "ha_tina.h"
+#include "probes_mysql.h"
+
+/*
+ uchar + uchar + ulonglong + ulonglong + ulonglong + ulonglong + uchar
+*/
+#define META_BUFFER_SIZE sizeof(uchar) + sizeof(uchar) + sizeof(ulonglong) \
+ + sizeof(ulonglong) + sizeof(ulonglong) + sizeof(ulonglong) + sizeof(uchar)
+#define TINA_CHECK_HEADER 254 // The number we use to determine corruption
+#define BLOB_MEMROOT_ALLOC_SIZE 8192
+
+/* The file extension */
+#define CSV_EXT ".CSV" // The data file
+#define CSN_EXT ".CSN" // Files used during repair and update
+#define CSM_EXT ".CSM" // Meta file
+
+struct ha_table_option_struct
+{
+ bool ietf_quotes;
+};
+
+ha_create_table_option csv_table_option_list[]=
+{
+ HA_TOPTION_BOOL("IETF_QUOTES", ietf_quotes, 0),
+ HA_TOPTION_END
+};
+
+static TINA_SHARE *get_share(const char *table_name, TABLE *table);
+static int free_share(TINA_SHARE *share);
+static int read_meta_file(File meta_file, ha_rows *rows);
+static int write_meta_file(File meta_file, ha_rows rows, bool dirty);
+
+extern "C" void tina_get_status(void* param, int concurrent_insert);
+extern "C" void tina_update_status(void* param);
+extern "C" my_bool tina_check_status(void* param);
+
+/* Stuff for shares */
+mysql_mutex_t tina_mutex;
+static HASH tina_open_tables;
+static handler *tina_create_handler(handlerton *hton,
+ TABLE_SHARE *table,
+ MEM_ROOT *mem_root);
+
+
+/*****************************************************************************
+ ** TINA tables
+ *****************************************************************************/
+
+/*
+ Used for sorting chains with qsort().
+*/
+int sort_set (tina_set *a, tina_set *b)
+{
+ /*
+ We assume that intervals do not intersect. So, it is enought to compare
+ any two points. Here we take start of intervals for comparison.
+ */
+ return ( a->begin > b->begin ? 1 : ( a->begin < b->begin ? -1 : 0 ) );
+}
+
+static uchar* tina_get_key(TINA_SHARE *share, size_t *length,
+ my_bool not_used __attribute__((unused)))
+{
+ *length=share->table_name_length;
+ return (uchar*) share->table_name;
+}
+
+static PSI_memory_key csv_key_memory_tina_share;
+static PSI_memory_key csv_key_memory_blobroot;
+static PSI_memory_key csv_key_memory_tina_set;
+static PSI_memory_key csv_key_memory_row;
+
+#ifdef HAVE_PSI_INTERFACE
+
+static PSI_mutex_key csv_key_mutex_tina, csv_key_mutex_TINA_SHARE_mutex;
+
+static PSI_mutex_info all_tina_mutexes[]=
+{
+ { &csv_key_mutex_tina, "tina", PSI_FLAG_GLOBAL},
+ { &csv_key_mutex_TINA_SHARE_mutex, "TINA_SHARE::mutex", 0}
+};
+
+static PSI_file_key csv_key_file_metadata, csv_key_file_data,
+ csv_key_file_update;
+
+static PSI_file_info all_tina_files[]=
+{
+ { &csv_key_file_metadata, "metadata", 0},
+ { &csv_key_file_data, "data", 0},
+ { &csv_key_file_update, "update", 0}
+};
+
+static PSI_memory_info all_tina_memory[]=
+{
+ { &csv_key_memory_tina_share, "TINA_SHARE", PSI_FLAG_GLOBAL},
+ { &csv_key_memory_blobroot, "blobroot", 0},
+ { &csv_key_memory_tina_set, "tina_set", 0},
+ { &csv_key_memory_row, "row", 0},
+ { &csv_key_memory_Transparent_file, "Transparent_file", 0}
+};
+
+static void init_tina_psi_keys(void)
+{
+ const char* category= "csv";
+ int count;
+
+ count= array_elements(all_tina_mutexes);
+ mysql_mutex_register(category, all_tina_mutexes, count);
+
+ count= array_elements(all_tina_files);
+ mysql_file_register(category, all_tina_files, count);
+
+ count= array_elements(all_tina_memory);
+ mysql_memory_register(category, all_tina_memory, count);
+}
+#endif /* HAVE_PSI_INTERFACE */
+
+/*
+ If frm_error() is called in table.cc this is called to find out what file
+ extensions exist for this handler.
+*/
+static const char *ha_tina_exts[] = {
+ CSV_EXT,
+ CSM_EXT,
+ CSN_EXT,
+ NullS
+};
+
+static int tina_init_func(void *p)
+{
+ handlerton *tina_hton;
+
+#ifdef HAVE_PSI_INTERFACE
+ init_tina_psi_keys();
+#endif
+
+ tina_hton= (handlerton *)p;
+ mysql_mutex_init(csv_key_mutex_tina, &tina_mutex, MY_MUTEX_INIT_FAST);
+ (void) my_hash_init(csv_key_memory_tina_share, &tina_open_tables,
+ system_charset_info, 32, 0, 0, (my_hash_get_key)
+ tina_get_key, 0, 0);
+ tina_hton->db_type= DB_TYPE_CSV_DB;
+ tina_hton->create= tina_create_handler;
+ tina_hton->flags= (HTON_CAN_RECREATE | HTON_SUPPORT_LOG_TABLES |
+ HTON_NO_PARTITION);
+ tina_hton->tablefile_extensions= ha_tina_exts;
+ tina_hton->table_options= csv_table_option_list;
+ return 0;
+}
+
+static int tina_done_func(void *p)
+{
+ my_hash_free(&tina_open_tables);
+ mysql_mutex_destroy(&tina_mutex);
+
+ return 0;
+}
+
+
+/*
+ Simple lock controls.
+*/
+static TINA_SHARE *get_share(const char *table_name, TABLE *table)
+{
+ TINA_SHARE *share;
+ char meta_file_name[FN_REFLEN];
+ MY_STAT file_stat; /* Stat information for the data file */
+ char *tmp_name;
+ uint length;
+
+ mysql_mutex_lock(&tina_mutex);
+ length=(uint) strlen(table_name);
+
+ /*
+ If share is not present in the hash, create a new share and
+ initialize its members.
+ */
+ if (!(share=(TINA_SHARE*) my_hash_search(&tina_open_tables, (uchar*)
+ table_name, length)))
+ {
+ if (!my_multi_malloc(csv_key_memory_tina_share, MYF(MY_WME | MY_ZEROFILL),
+ &share, sizeof(*share), &tmp_name, length+1, NullS))
+ {
+ mysql_mutex_unlock(&tina_mutex);
+ return NULL;
+ }
+
+ share->use_count= 0;
+ share->is_log_table= FALSE;
+ share->table_name_length= length;
+ share->table_name= tmp_name;
+ share->crashed= FALSE;
+ share->rows_recorded= 0;
+ share->update_file_opened= FALSE;
+ share->tina_write_opened= FALSE;
+ share->data_file_version= 0;
+ strmov(share->table_name, table_name);
+ fn_format(share->data_file_name, table_name, "", CSV_EXT,
+ MY_REPLACE_EXT|MY_UNPACK_FILENAME);
+ fn_format(meta_file_name, table_name, "", CSM_EXT,
+ MY_REPLACE_EXT|MY_UNPACK_FILENAME);
+
+ if (mysql_file_stat(csv_key_file_data,
+ share->data_file_name, &file_stat, MYF(MY_WME)) == NULL)
+ goto error;
+ share->saved_data_file_length= file_stat.st_size;
+
+ if (my_hash_insert(&tina_open_tables, (uchar*) share))
+ goto error;
+ thr_lock_init(&share->lock);
+ mysql_mutex_init(csv_key_mutex_TINA_SHARE_mutex,
+ &share->mutex, MY_MUTEX_INIT_FAST);
+
+ /*
+ Open or create the meta file. In the latter case, we'll get
+ an error during read_meta_file and mark the table as crashed.
+ Usually this will result in auto-repair, and we will get a good
+ meta-file in the end.
+ */
+ if (((share->meta_file= mysql_file_open(csv_key_file_metadata,
+ meta_file_name,
+ O_RDWR|O_CREAT,
+ MYF(MY_WME))) == -1) ||
+ read_meta_file(share->meta_file, &share->rows_recorded))
+ share->crashed= TRUE;
+ }
+
+ share->use_count++;
+ mysql_mutex_unlock(&tina_mutex);
+
+ return share;
+
+error:
+ mysql_mutex_unlock(&tina_mutex);
+ my_free(share);
+
+ return NULL;
+}
+
+
+/*
+ Read CSV meta-file
+
+ SYNOPSIS
+ read_meta_file()
+ meta_file The meta-file filedes
+ ha_rows Pointer to the var we use to store rows count.
+ These are read from the meta-file.
+
+ DESCRIPTION
+
+ Read the meta-file info. For now we are only interested in
+ rows counf, crashed bit and magic number.
+
+ RETURN
+ 0 - OK
+ non-zero - error occurred
+*/
+
+static int read_meta_file(File meta_file, ha_rows *rows)
+{
+ uchar meta_buffer[META_BUFFER_SIZE];
+ uchar *ptr= meta_buffer;
+
+ DBUG_ENTER("ha_tina::read_meta_file");
+
+ mysql_file_seek(meta_file, 0, MY_SEEK_SET, MYF(0));
+ if (mysql_file_read(meta_file, (uchar*)meta_buffer, META_BUFFER_SIZE, 0)
+ != META_BUFFER_SIZE)
+ DBUG_RETURN(my_errno= HA_ERR_CRASHED_ON_USAGE);
+
+ /*
+ Parse out the meta data, we ignore version at the moment
+ */
+
+ ptr+= sizeof(uchar)*2; // Move past header
+ *rows= (ha_rows)uint8korr(ptr);
+ ptr+= sizeof(ulonglong); // Move past rows
+ /*
+ Move past check_point, auto_increment and forced_flushes fields.
+ They are present in the format, but we do not use them yet.
+ */
+ ptr+= 3*sizeof(ulonglong);
+
+ /* check crashed bit and magic number */
+ if ((meta_buffer[0] != (uchar)TINA_CHECK_HEADER) ||
+ ((bool)(*ptr)== TRUE))
+ DBUG_RETURN(HA_ERR_CRASHED_ON_USAGE);
+
+ mysql_file_sync(meta_file, MYF(MY_WME));
+
+ DBUG_RETURN(0);
+}
+
+
+/*
+ Write CSV meta-file
+
+ SYNOPSIS
+ write_meta_file()
+ meta_file The meta-file filedes
+ ha_rows The number of rows we have in the datafile.
+ dirty A flag, which marks whether we have a corrupt table
+
+ DESCRIPTION
+
+ Write meta-info the the file. Only rows count, crashed bit and
+ magic number matter now.
+
+ RETURN
+ 0 - OK
+ non-zero - error occurred
+*/
+
+static int write_meta_file(File meta_file, ha_rows rows, bool dirty)
+{
+ uchar meta_buffer[META_BUFFER_SIZE];
+ uchar *ptr= meta_buffer;
+
+ DBUG_ENTER("ha_tina::write_meta_file");
+
+ *ptr= (uchar)TINA_CHECK_HEADER;
+ ptr+= sizeof(uchar);
+ *ptr= (uchar)TINA_VERSION;
+ ptr+= sizeof(uchar);
+ int8store(ptr, (ulonglong)rows);
+ ptr+= sizeof(ulonglong);
+ memset(ptr, 0, 3*sizeof(ulonglong));
+ /*
+ Skip over checkpoint, autoincrement and forced_flushes fields.
+ We'll need them later.
+ */
+ ptr+= 3*sizeof(ulonglong);
+ *ptr= (uchar)dirty;
+
+ mysql_file_seek(meta_file, 0, MY_SEEK_SET, MYF(0));
+ if (mysql_file_write(meta_file, (uchar *)meta_buffer, META_BUFFER_SIZE, 0)
+ != META_BUFFER_SIZE)
+ DBUG_RETURN(-1);
+
+ mysql_file_sync(meta_file, MYF(MY_WME));
+
+ DBUG_RETURN(0);
+}
+
+bool ha_tina::check_and_repair(THD *thd)
+{
+ HA_CHECK_OPT check_opt;
+ DBUG_ENTER("ha_tina::check_and_repair");
+
+ check_opt.init();
+
+ DBUG_RETURN(repair(thd, &check_opt));
+}
+
+
+int ha_tina::init_tina_writer()
+{
+ DBUG_ENTER("ha_tina::init_tina_writer");
+
+ /*
+ Mark the file as crashed. We will set the flag back when we close
+ the file. In the case of the crash it will remain marked crashed,
+ which enforce recovery.
+ */
+ (void)write_meta_file(share->meta_file, share->rows_recorded, TRUE);
+
+ if ((share->tina_write_filedes=
+ mysql_file_open(csv_key_file_data,
+ share->data_file_name, O_RDWR|O_APPEND,
+ MYF(MY_WME))) == -1)
+ {
+ DBUG_PRINT("info", ("Could not open tina file writes"));
+ share->crashed= TRUE;
+ DBUG_RETURN(my_errno ? my_errno : -1);
+ }
+ share->tina_write_opened= TRUE;
+
+ DBUG_RETURN(0);
+}
+
+
+bool ha_tina::is_crashed() const
+{
+ DBUG_ENTER("ha_tina::is_crashed");
+ DBUG_RETURN(share->crashed);
+}
+
+/*
+ Free lock controls.
+*/
+static int free_share(TINA_SHARE *share)
+{
+ DBUG_ENTER("ha_tina::free_share");
+ mysql_mutex_lock(&tina_mutex);
+ int result_code= 0;
+ if (!--share->use_count){
+ /* Write the meta file. Mark it as crashed if needed. */
+ if (share->meta_file != -1)
+ {
+ (void)write_meta_file(share->meta_file, share->rows_recorded,
+ share->crashed ? TRUE :FALSE);
+ if (mysql_file_close(share->meta_file, MYF(0)))
+ result_code= 1;
+ }
+ if (share->tina_write_opened)
+ {
+ if (mysql_file_close(share->tina_write_filedes, MYF(0)))
+ result_code= 1;
+ share->tina_write_opened= FALSE;
+ }
+
+ my_hash_delete(&tina_open_tables, (uchar*) share);
+ thr_lock_delete(&share->lock);
+ mysql_mutex_destroy(&share->mutex);
+ my_free(share);
+ }
+ mysql_mutex_unlock(&tina_mutex);
+
+ DBUG_RETURN(result_code);
+}
+
+
+/*
+ This function finds the end of a line and returns the length
+ of the line ending.
+
+ We support three kinds of line endings:
+ '\r' -- Old Mac OS line ending
+ '\n' -- Traditional Unix and Mac OS X line ending
+ '\r''\n' -- DOS\Windows line ending
+*/
+
+my_off_t find_eoln_buff(Transparent_file *data_buff, my_off_t begin,
+ my_off_t end, int *eoln_len)
+{
+ *eoln_len= 0;
+
+ for (my_off_t x= begin; x < end; x++)
+ {
+ /* Unix (includes Mac OS X) */
+ if (data_buff->get_value(x) == '\n')
+ *eoln_len= 1;
+ else
+ if (data_buff->get_value(x) == '\r') // Mac or Dos
+ {
+ /* old Mac line ending */
+ if (x + 1 == end || (data_buff->get_value(x + 1) != '\n'))
+ *eoln_len= 1;
+ else // DOS style ending
+ *eoln_len= 2;
+ }
+
+ if (*eoln_len) // end of line was found
+ return x;
+ }
+
+ return 0;
+}
+
+
+static handler *tina_create_handler(handlerton *hton,
+ TABLE_SHARE *table,
+ MEM_ROOT *mem_root)
+{
+ return new (mem_root) ha_tina(hton, table);
+}
+
+
+ha_tina::ha_tina(handlerton *hton, TABLE_SHARE *table_arg)
+ :handler(hton, table_arg),
+ /*
+ These definitions are found in handler.h
+ They are not probably completely right.
+ */
+ current_position(0), next_position(0), local_saved_data_file_length(0),
+ file_buff(0), chain_alloced(0), chain_size(DEFAULT_CHAIN_LENGTH),
+ local_data_file_version(0), records_is_known(0)
+{
+ /* Set our original buffers from pre-allocated memory */
+ buffer.set((char*)byte_buffer, IO_SIZE, &my_charset_bin);
+ chain= chain_buffer;
+ file_buff= new Transparent_file();
+ init_alloc_root(csv_key_memory_blobroot, &blobroot, BLOB_MEMROOT_ALLOC_SIZE,
+ 0, MYF(0));
+}
+
+
+/*
+ Encode a buffer into the quoted format.
+*/
+
+int ha_tina::encode_quote(const uchar *buf)
+{
+ char attribute_buffer[1024];
+ String attribute(attribute_buffer, sizeof(attribute_buffer),
+ &my_charset_bin);
+ bool ietf_quotes= table_share->option_struct->ietf_quotes;
+ MY_BITMAP *org_bitmap= dbug_tmp_use_all_columns(table, &table->read_set);
+ buffer.length(0);
+
+ for (Field **field=table->field ; *field ; field++)
+ {
+ const char *ptr;
+ const char *end_ptr;
+ const bool was_null= (*field)->is_null();
+
+ /*
+ assistance for backwards compatibility in production builds.
+ note: this will not work for ENUM columns.
+ */
+ if (was_null)
+ {
+ (*field)->set_default();
+ (*field)->set_notnull();
+ }
+
+ (*field)->val_str(&attribute,&attribute);
+
+ if (was_null)
+ (*field)->set_null();
+
+ if ((*field)->str_needs_quotes())
+ {
+ ptr= attribute.ptr();
+ end_ptr= attribute.length() + ptr;
+
+ /*
+ Ensure that buffer is big enough. This will also speed things up
+ as we don't have to do any new allocation in the loop below
+ */
+ if (buffer.realloc(buffer.length() + attribute.length()*2+2))
+ return 0; // Failure
+
+ buffer.append('"');
+
+ for (; ptr < end_ptr; ptr++)
+ {
+ if (*ptr == '"')
+ {
+ buffer.append(ietf_quotes ? '"' : '\\');
+ buffer.append('"');
+ }
+ else if (*ptr == '\r')
+ {
+ buffer.append('\\');
+ buffer.append('r');
+ }
+ else if (*ptr == '\\')
+ {
+ buffer.append('\\');
+ buffer.append('\\');
+ }
+ else if (*ptr == '\n')
+ {
+ buffer.append('\\');
+ buffer.append('n');
+ }
+ else
+ buffer.append(*ptr);
+ }
+ buffer.append('"');
+ }
+ else
+ {
+ buffer.append(attribute);
+ }
+
+ buffer.append(',');
+ }
+ // Remove the comma, add a line feed
+ buffer.length(buffer.length() - 1);
+ buffer.append('\n');
+
+ //buffer.replace(buffer.length(), 0, "\n", 1);
+
+ dbug_tmp_restore_column_map(&table->read_set, org_bitmap);
+ return (buffer.length());
+}
+
+/*
+ chain_append() adds delete positions to the chain that we use to keep
+ track of space. Then the chain will be used to cleanup "holes", occurred
+ due to deletes and updates.
+*/
+int ha_tina::chain_append()
+{
+ if ( chain_ptr != chain && (chain_ptr -1)->end == current_position)
+ (chain_ptr -1)->end= next_position;
+ else
+ {
+ /* We set up for the next position */
+ if ((off_t)(chain_ptr - chain) == (chain_size -1))
+ {
+ my_off_t location= chain_ptr - chain;
+ chain_size += DEFAULT_CHAIN_LENGTH;
+ if (chain_alloced)
+ {
+ if ((chain= (tina_set *) my_realloc(csv_key_memory_tina_set,
+ (uchar*)chain, chain_size,
+ MYF(MY_WME))) == NULL)
+ return -1;
+ }
+ else
+ {
+ tina_set *ptr= (tina_set *) my_malloc(csv_key_memory_tina_set,
+ chain_size * sizeof(tina_set),
+ MYF(MY_WME));
+ memcpy(ptr, chain, DEFAULT_CHAIN_LENGTH * sizeof(tina_set));
+ chain= ptr;
+ chain_alloced++;
+ }
+ chain_ptr= chain + location;
+ }
+ chain_ptr->begin= current_position;
+ chain_ptr->end= next_position;
+ chain_ptr++;
+ }
+
+ return 0;
+}
+
+
+/*
+ Scans for a row.
+*/
+int ha_tina::find_current_row(uchar *buf)
+{
+ my_off_t end_offset, curr_offset= current_position;
+ int eoln_len;
+ int error;
+ bool read_all;
+ bool ietf_quotes= table_share->option_struct->ietf_quotes;
+ DBUG_ENTER("ha_tina::find_current_row");
+
+ free_root(&blobroot, MYF(0));
+
+ /*
+ We do not read further then local_saved_data_file_length in order
+ not to conflict with undergoing concurrent insert.
+ */
+ if ((end_offset=
+ find_eoln_buff(file_buff, current_position,
+ local_saved_data_file_length, &eoln_len)) == 0)
+ DBUG_RETURN(HA_ERR_END_OF_FILE);
+
+ /* We must read all columns in case a table is opened for update */
+ read_all= !bitmap_is_clear_all(table->write_set);
+ /* Avoid asserts in ::store() for columns that are not going to be updated */
+ MY_BITMAP *org_bitmap= dbug_tmp_use_all_columns(table, &table->write_set);
+ error= HA_ERR_CRASHED_ON_USAGE;
+
+ memset(buf, 0, table->s->null_bytes);
+
+ /*
+ Parse the line obtained using the following algorithm
+
+ BEGIN
+ 1) Store the EOL (end of line) for the current row
+ 2) Until all the fields in the current query have not been
+ filled
+ 2.1) If the current character is a quote
+ 2.1.1) Until EOL has not been reached
+ a) If end of current field is reached, move
+ to next field and jump to step 2.3
+ b) If current character is a \\ handle
+ \\n, \\r, \\, and \\" if not in ietf_quotes mode
+ c) if in ietf_quotes mode and the current character is
+ a ", handle ""
+ d) else append the current character into the buffer
+ before checking that EOL has not been reached.
+ 2.2) If the current character does not begin with a quote
+ 2.2.1) Until EOL has not been reached
+ a) If the end of field has been reached move to the
+ next field and jump to step 2.3
+ b) If current character begins with \\ handle
+ \\n, \\r, \\, \\"
+ c) else append the current character into the buffer
+ before checking that EOL has not been reached.
+ 2.3) Store the current field value and jump to 2)
+ TERMINATE
+ */
+
+ for (Field **field=table->field ; *field ; field++)
+ {
+ char curr_char;
+
+ buffer.length(0);
+ if (curr_offset >= end_offset)
+ goto err;
+ curr_char= file_buff->get_value(curr_offset);
+ /* Handle the case where the first character is a quote */
+ if (curr_char == '"')
+ {
+ /* Increment past the first quote */
+ curr_offset++;
+
+ /* Loop through the row to extract the values for the current field */
+ for ( ; curr_offset < end_offset; curr_offset++)
+ {
+ curr_char= file_buff->get_value(curr_offset);
+ /* check for end of the current field */
+ if (curr_char == '"' &&
+ (curr_offset == end_offset - 1 ||
+ file_buff->get_value(curr_offset + 1) == ','))
+ {
+ /* Move past the , and the " */
+ curr_offset+= 2;
+ break;
+ }
+ if (ietf_quotes && curr_char == '"'
+ && file_buff->get_value(curr_offset + 1) == '"')
+ {
+ /* Embedded IETF quote */
+ curr_offset++;
+ buffer.append('"');
+ }
+ else if (curr_char == '\\' && curr_offset != (end_offset - 1))
+ {
+ /* A quote followed by something else than a comma, end of line, or
+ (in IETF mode) another quote will be handled as a regular
+ character. */
+ curr_offset++;
+ curr_char= file_buff->get_value(curr_offset);
+ if (curr_char == 'r')
+ buffer.append('\r');
+ else if (curr_char == 'n' )
+ buffer.append('\n');
+ else if (curr_char == '\\' || (!ietf_quotes && curr_char == '"'))
+ buffer.append(curr_char);
+ else /* This could only happed with an externally created file */
+ {
+ buffer.append('\\');
+ buffer.append(curr_char);
+ }
+ }
+ else // ordinary symbol
+ {
+ /*
+ If we are at final symbol and no last quote was found =>
+ we are working with a damaged file.
+ */
+ if (curr_offset == end_offset - 1)
+ goto err;
+ buffer.append(curr_char);
+ }
+ }
+ }
+ else
+ {
+ for ( ; curr_offset < end_offset; curr_offset++)
+ {
+ curr_char= file_buff->get_value(curr_offset);
+ /* Move past the ,*/
+ if (curr_char == ',')
+ {
+ curr_offset++;
+ break;
+ }
+ if (curr_char == '\\' && curr_offset != (end_offset - 1))
+ {
+ curr_offset++;
+ curr_char= file_buff->get_value(curr_offset);
+ if (curr_char == 'r')
+ buffer.append('\r');
+ else if (curr_char == 'n' )
+ buffer.append('\n');
+ else if (curr_char == '\\' || curr_char == '"')
+ buffer.append(curr_char);
+ else /* This could only happed with an externally created file */
+ {
+ buffer.append('\\');
+ buffer.append(curr_char);
+ }
+ }
+ else
+ {
+ /*
+ We are at the final symbol and a quote was found for the
+ unquoted field => We are working with a damaged field.
+ */
+ if (curr_offset == end_offset - 1 && curr_char == '"')
+ goto err;
+ buffer.append(curr_char);
+ }
+ }
+ }
+
+ if (read_all || bitmap_is_set(table->read_set, (*field)->field_index))
+ {
+ bool is_enum= ((*field)->real_type() == MYSQL_TYPE_ENUM);
+ /*
+ Here CHECK_FIELD_WARN checks that all values in the csv file are valid
+ which is normally the case, if they were written by
+ INSERT -> ha_tina::write_row. '0' values on ENUM fields are considered
+ invalid by Field_enum::store() but it can store them on INSERT anyway.
+ Thus, for enums we silence the warning, as it doesn't really mean
+ an invalid value.
+ */
+ if ((*field)->store_text(buffer.ptr(), buffer.length(), buffer.charset(),
+ is_enum ? CHECK_FIELD_IGNORE : CHECK_FIELD_WARN))
+ {
+ if (!is_enum)
+ goto err;
+ }
+ if ((*field)->flags & BLOB_FLAG)
+ {
+ Field_blob *blob= *(Field_blob**) field;
+ uchar *src, *tgt;
+ uint length, packlength;
+
+ packlength= blob->pack_length_no_ptr();
+ length= blob->get_length(blob->ptr);
+ memcpy(&src, blob->ptr + packlength, sizeof(char*));
+ if (src)
+ {
+ tgt= (uchar*) alloc_root(&blobroot, length);
+ bmove(tgt, src, length);
+ memcpy(blob->ptr + packlength, &tgt, sizeof(char*));
+ }
+ }
+ }
+ }
+ next_position= end_offset + eoln_len;
+ error= 0;
+
+err:
+ dbug_tmp_restore_column_map(&table->write_set, org_bitmap);
+
+ DBUG_RETURN(error);
+}
+
+/*
+ Three functions below are needed to enable concurrent insert functionality
+ for CSV engine. For more details see mysys/thr_lock.c
+*/
+
+my_bool tina_get_status(void* param, my_bool concurrent_insert)
+{
+ ha_tina *tina= (ha_tina*) param;
+ tina->get_status();
+ return 0;
+}
+
+void tina_update_status(void* param)
+{
+ ha_tina *tina= (ha_tina*) param;
+ tina->update_status();
+}
+
+/* this should exist and return 0 for concurrent insert to work */
+my_bool tina_check_status(void* param)
+{
+ return 0;
+}
+
+/*
+ Save the state of the table
+
+ SYNOPSIS
+ get_status()
+
+ DESCRIPTION
+ This function is used to retrieve the file length. During the lock
+ phase of concurrent insert. For more details see comment to
+ ha_tina::update_status below.
+*/
+
+void ha_tina::get_status()
+{
+ if (share->is_log_table)
+ {
+ /*
+ We have to use mutex to follow pthreads memory visibility
+ rules for share->saved_data_file_length
+ */
+ mysql_mutex_lock(&share->mutex);
+ local_saved_data_file_length= share->saved_data_file_length;
+ mysql_mutex_unlock(&share->mutex);
+ return;
+ }
+ local_saved_data_file_length= share->saved_data_file_length;
+}
+
+
+/*
+ Correct the state of the table. Called by unlock routines
+ before the write lock is released.
+
+ SYNOPSIS
+ update_status()
+
+ DESCRIPTION
+ When we employ concurrent insert lock, we save current length of the file
+ during the lock phase. We do not read further saved value, as we don't
+ want to interfere with undergoing concurrent insert. Writers update file
+ length info during unlock with update_status().
+
+ NOTE
+ For log tables concurrent insert works different. The reason is that
+ log tables are always opened and locked. And as they do not unlock
+ tables, the file length after writes should be updated in a different
+ way. For this purpose we need is_log_table flag. When this flag is set
+ we call update_status() explicitly after each row write.
+*/
+
+void ha_tina::update_status()
+{
+ /* correct local_saved_data_file_length for writers */
+ share->saved_data_file_length= local_saved_data_file_length;
+}
+
+
+/*
+ Open a database file. Keep in mind that tables are caches, so
+ this will not be called for every request. Any sort of positions
+ that need to be reset should be kept in the ::extra() call.
+*/
+int ha_tina::open(const char *name, int mode, uint open_options)
+{
+ DBUG_ENTER("ha_tina::open");
+
+ if (!(share= get_share(name, table)))
+ DBUG_RETURN(HA_ERR_OUT_OF_MEM);
+
+ if (share->crashed && !(open_options & HA_OPEN_FOR_REPAIR))
+ {
+ free_share(share);
+ DBUG_RETURN(my_errno ? my_errno : HA_ERR_CRASHED_ON_USAGE);
+ }
+
+ local_data_file_version= share->data_file_version;
+ if ((data_file= mysql_file_open(csv_key_file_data,
+ share->data_file_name,
+ O_RDONLY, MYF(MY_WME))) == -1)
+ {
+ free_share(share);
+ DBUG_RETURN(my_errno ? my_errno : -1);
+ }
+
+ /*
+ Init locking. Pass handler object to the locking routines,
+ so that they could save/update local_saved_data_file_length value
+ during locking. This is needed to enable concurrent inserts.
+ */
+ thr_lock_data_init(&share->lock, &lock, (void*) this);
+ ref_length= sizeof(my_off_t);
+ init_alloc_root(csv_key_memory_blobroot, &blobroot, BLOB_MEMROOT_ALLOC_SIZE,
+ 0, MYF(0));
+
+ share->lock.get_status= tina_get_status;
+ share->lock.update_status= tina_update_status;
+ share->lock.check_status= tina_check_status;
+
+ DBUG_RETURN(0);
+}
+
+
+/*
+ Close a database file. We remove ourselves from the shared strucutre.
+ If it is empty we destroy it.
+*/
+int ha_tina::close(void)
+{
+ int rc= 0;
+ DBUG_ENTER("ha_tina::close");
+ free_root(&blobroot, MYF(0));
+ rc= mysql_file_close(data_file, MYF(0));
+ DBUG_RETURN(free_share(share) || rc);
+}
+
+/*
+ This is an INSERT. At the moment this handler just seeks to the end
+ of the file and appends the data. In an error case it really should
+ just truncate to the original position (this is not done yet).
+*/
+int ha_tina::write_row(const uchar * buf)
+{
+ int size;
+ DBUG_ENTER("ha_tina::write_row");
+
+ if (share->crashed)
+ DBUG_RETURN(HA_ERR_CRASHED_ON_USAGE);
+
+ size= encode_quote(buf);
+
+ if (!share->tina_write_opened)
+ if (init_tina_writer())
+ DBUG_RETURN(-1);
+
+ /* use pwrite, as concurrent reader could have changed the position */
+ if (mysql_file_write(share->tina_write_filedes, (uchar*)buffer.ptr(), size,
+ MYF(MY_WME | MY_NABP)))
+ DBUG_RETURN(-1);
+
+ /* update local copy of the max position to see our own changes */
+ local_saved_data_file_length+= size;
+
+ /* update shared info */
+ mysql_mutex_lock(&share->mutex);
+ share->rows_recorded++;
+ /* update status for the log tables */
+ if (share->is_log_table)
+ update_status();
+ mysql_mutex_unlock(&share->mutex);
+
+ stats.records++;
+ DBUG_RETURN(0);
+}
+
+
+int ha_tina::open_update_temp_file_if_needed()
+{
+ char updated_fname[FN_REFLEN];
+
+ if (!share->update_file_opened)
+ {
+ if ((update_temp_file=
+ mysql_file_create(csv_key_file_update,
+ fn_format(updated_fname, share->table_name,
+ "", CSN_EXT,
+ MY_REPLACE_EXT | MY_UNPACK_FILENAME),
+ 0, O_RDWR | O_TRUNC, MYF(MY_WME))) < 0)
+ return 1;
+ share->update_file_opened= TRUE;
+ temp_file_length= 0;
+ }
+ return 0;
+}
+
+/*
+ This is called for an update.
+ Make sure you put in code to increment the auto increment.
+ Currently auto increment is not being
+ fixed since autoincrements have yet to be added to this table handler.
+ This will be called in a table scan right before the previous ::rnd_next()
+ call.
+*/
+int ha_tina::update_row(const uchar * old_data, const uchar * new_data)
+{
+ int size;
+ int rc= -1;
+ DBUG_ENTER("ha_tina::update_row");
+
+ size= encode_quote(new_data);
+
+ /*
+ During update we mark each updating record as deleted
+ (see the chain_append()) then write new one to the temporary data file.
+ At the end of the sequence in the rnd_end() we append all non-marked
+ records from the data file to the temporary data file then rename it.
+ The temp_file_length is used to calculate new data file length.
+ */
+ if (chain_append())
+ goto err;
+
+ if (open_update_temp_file_if_needed())
+ goto err;
+
+ if (mysql_file_write(update_temp_file, (uchar*)buffer.ptr(), size,
+ MYF(MY_WME | MY_NABP)))
+ goto err;
+ temp_file_length+= size;
+ rc= 0;
+
+ /* UPDATE should never happen on the log tables */
+ DBUG_ASSERT(!share->is_log_table);
+
+err:
+ DBUG_PRINT("info",("rc = %d", rc));
+ DBUG_RETURN(rc);
+}
+
+
+/*
+ Deletes a row. First the database will find the row, and then call this
+ method. In the case of a table scan, the previous call to this will be
+ the ::rnd_next() that found this row.
+ The exception to this is an ORDER BY. This will cause the table handler
+ to walk the table noting the positions of all rows that match a query.
+ The table will then be deleted/positioned based on the ORDER (so RANDOM,
+ DESC, ASC).
+*/
+int ha_tina::delete_row(const uchar * buf)
+{
+ DBUG_ENTER("ha_tina::delete_row");
+
+ if (chain_append())
+ DBUG_RETURN(-1);
+
+ stats.records--;
+ /* Update shared info */
+ DBUG_ASSERT(share->rows_recorded);
+ mysql_mutex_lock(&share->mutex);
+ share->rows_recorded--;
+ mysql_mutex_unlock(&share->mutex);
+
+ /* DELETE should never happen on the log table */
+ DBUG_ASSERT(!share->is_log_table);
+
+ DBUG_RETURN(0);
+}
+
+
+/**
+ @brief Initialize the data file.
+
+ @details Compare the local version of the data file with the shared one.
+ If they differ, there are some changes behind and we have to reopen
+ the data file to make the changes visible.
+ Call @c file_buff->init_buff() at the end to read the beginning of the
+ data file into buffer.
+
+ @retval 0 OK.
+ @retval 1 There was an error.
+*/
+
+int ha_tina::init_data_file()
+{
+ if (local_data_file_version != share->data_file_version)
+ {
+ local_data_file_version= share->data_file_version;
+ if (mysql_file_close(data_file, MYF(0)) ||
+ (data_file= mysql_file_open(csv_key_file_data,
+ share->data_file_name, O_RDONLY,
+ MYF(MY_WME))) == -1)
+ return my_errno ? my_errno : -1;
+ }
+ file_buff->init_buff(data_file);
+ return 0;
+}
+
+
+/*
+ All table scans call this first.
+ The order of a table scan is:
+
+ ha_tina::store_lock
+ ha_tina::external_lock
+ ha_tina::info
+ ha_tina::rnd_init
+ ha_tina::extra
+ ENUM HA_EXTRA_CACHE Cash record in HA_rrnd()
+ ha_tina::rnd_next
+ ha_tina::rnd_next
+ ha_tina::rnd_next
+ ha_tina::rnd_next
+ ha_tina::rnd_next
+ ha_tina::rnd_next
+ ha_tina::rnd_next
+ ha_tina::rnd_next
+ ha_tina::rnd_next
+ ha_tina::extra
+ ENUM HA_EXTRA_NO_CACHE End cacheing of records (def)
+ ha_tina::external_lock
+ ha_tina::extra
+ ENUM HA_EXTRA_RESET Reset database to after open
+
+ Each call to ::rnd_next() represents a row returned in the can. When no more
+ rows can be returned, rnd_next() returns a value of HA_ERR_END_OF_FILE.
+ The ::info() call is just for the optimizer.
+
+*/
+
+int ha_tina::rnd_init(bool scan)
+{
+ DBUG_ENTER("ha_tina::rnd_init");
+
+ /* set buffer to the beginning of the file */
+ if (share->crashed || init_data_file())
+ DBUG_RETURN(HA_ERR_CRASHED_ON_USAGE);
+
+ current_position= next_position= 0;
+ stats.records= 0;
+ records_is_known= found_end_of_file= 0;
+ chain_ptr= chain;
+
+ DBUG_RETURN(0);
+}
+
+/*
+ ::rnd_next() does all the heavy lifting for a table scan. You will need to
+ populate *buf with the correct field data. You can walk the field to
+ determine at what position you should store the data (take a look at how
+ ::find_current_row() works). The structure is something like:
+ 0Foo Dog Friend
+ The first offset is for the first attribute. All space before that is
+ reserved for null count.
+ Basically this works as a mask for which rows are nulled (compared to just
+ empty).
+ This table handler doesn't do nulls and does not know the difference between
+ NULL and "". This is ok since this table handler is for spreadsheets and
+ they don't know about them either :)
+*/
+int ha_tina::rnd_next(uchar *buf)
+{
+ int rc;
+ DBUG_ENTER("ha_tina::rnd_next");
+ MYSQL_READ_ROW_START(table_share->db.str, table_share->table_name.str,
+ TRUE);
+
+ if (share->crashed)
+ {
+ rc= HA_ERR_CRASHED_ON_USAGE;
+ goto end;
+ }
+
+ current_position= next_position;
+
+ /* don't scan an empty file */
+ if (!local_saved_data_file_length)
+ {
+ rc= HA_ERR_END_OF_FILE;
+ goto end;
+ }
+
+ if ((rc= find_current_row(buf)))
+ goto end;
+
+ stats.records++;
+ rc= 0;
+end:
+ found_end_of_file= (rc == HA_ERR_END_OF_FILE);
+ MYSQL_READ_ROW_DONE(rc);
+ DBUG_RETURN(rc);
+}
+
+/*
+ In the case of an order by rows will need to be sorted.
+ ::position() is called after each call to ::rnd_next(),
+ the data it stores is to a byte array. You can store this
+ data via my_store_ptr(). ref_length is a variable defined to the
+ class that is the sizeof() of position being stored. In our case
+ its just a position. Look at the bdb code if you want to see a case
+ where something other then a number is stored.
+*/
+void ha_tina::position(const uchar *record)
+{
+ DBUG_ENTER("ha_tina::position");
+ my_store_ptr(ref, ref_length, current_position);
+ DBUG_VOID_RETURN;
+}
+
+
+/*
+ Used to fetch a row from a posiion stored with ::position().
+ my_get_ptr() retrieves the data for you.
+*/
+
+int ha_tina::rnd_pos(uchar * buf, uchar *pos)
+{
+ int rc;
+ DBUG_ENTER("ha_tina::rnd_pos");
+ MYSQL_READ_ROW_START(table_share->db.str, table_share->table_name.str,
+ FALSE);
+ current_position= my_get_ptr(pos,ref_length);
+ rc= find_current_row(buf);
+ MYSQL_READ_ROW_DONE(rc);
+ DBUG_RETURN(rc);
+}
+
+/*
+ ::info() is used to return information to the optimizer.
+ Currently this table handler doesn't implement most of the fields
+ really needed. SHOW also makes use of this data
+*/
+int ha_tina::info(uint flag)
+{
+ DBUG_ENTER("ha_tina::info");
+ /* This is a lie, but you don't want the optimizer to see zero or 1 */
+ if (!records_is_known && stats.records < 2)
+ stats.records= 2;
+ DBUG_RETURN(0);
+}
+
+/*
+ Grab bag of flags that are sent to the able handler every so often.
+ HA_EXTRA_RESET and HA_EXTRA_RESET_STATE are the most frequently called.
+ You are not required to implement any of these.
+*/
+int ha_tina::extra(enum ha_extra_function operation)
+{
+ DBUG_ENTER("ha_tina::extra");
+ switch (operation) {
+ case HA_EXTRA_MARK_AS_LOG_TABLE:
+ {
+ mysql_mutex_lock(&share->mutex);
+ share->is_log_table= TRUE;
+ mysql_mutex_unlock(&share->mutex);
+ }
+ break;
+ case HA_EXTRA_FLUSH:
+ mysql_mutex_lock(&share->mutex);
+ if (share->tina_write_opened)
+ {
+ (void)write_meta_file(share->meta_file, share->rows_recorded,
+ share->crashed ? TRUE :FALSE);
+ mysql_file_close(share->tina_write_filedes, MYF(0));
+ share->tina_write_opened= FALSE;
+ }
+ mysql_mutex_unlock(&share->mutex);
+ break;
+ default:
+ break;
+ }
+ DBUG_RETURN(0);
+}
+
+
+/*
+ Set end_pos to the last valid byte of continuous area, closest
+ to the given "hole", stored in the buffer. "Valid" here means,
+ not listed in the chain of deleted records ("holes").
+*/
+bool ha_tina::get_write_pos(my_off_t *end_pos, tina_set *closest_hole)
+{
+ if (closest_hole == chain_ptr) /* no more chains */
+ *end_pos= file_buff->end();
+ else
+ *end_pos= MY_MIN(file_buff->end(), closest_hole->begin);
+ return (closest_hole != chain_ptr) && (*end_pos == closest_hole->begin);
+}
+
+
+/*
+ Called after each table scan. In particular after deletes,
+ and updates. In the last case we employ chain of deleted
+ slots to clean up all of the dead space we have collected while
+ performing deletes/updates.
+*/
+int ha_tina::rnd_end()
+{
+ char updated_fname[FN_REFLEN];
+ my_off_t file_buffer_start= 0;
+ DBUG_ENTER("ha_tina::rnd_end");
+
+ records_is_known= found_end_of_file;
+
+ if ((chain_ptr - chain) > 0)
+ {
+ tina_set *ptr= chain;
+
+ /*
+ Re-read the beginning of a file (as the buffer should point to the
+ end of file after the scan).
+ */
+ file_buff->init_buff(data_file);
+
+ /*
+ The sort is needed when there were updates/deletes with random orders.
+ It sorts so that we move the firts blocks to the beginning.
+ */
+ my_qsort(chain, (size_t)(chain_ptr - chain), sizeof(tina_set),
+ (qsort_cmp)sort_set);
+
+ my_off_t write_begin= 0, write_end;
+
+ /* create the file to write updated table if it wasn't yet created */
+ if (open_update_temp_file_if_needed())
+ DBUG_RETURN(-1);
+
+ /* write the file with updated info */
+ while ((file_buffer_start != (my_off_t)-1)) // while not end of file
+ {
+ bool in_hole= get_write_pos(&write_end, ptr);
+ my_off_t write_length= write_end - write_begin;
+
+ /* if there is something to write, write it */
+ if (write_length)
+ {
+ if (mysql_file_write(update_temp_file,
+ (uchar*) (file_buff->ptr() +
+ (write_begin - file_buff->start())),
+ (size_t)write_length, MYF(MY_WME+MY_NABP)))
+ goto error;
+ temp_file_length+= write_length;
+ }
+ if (in_hole)
+ {
+ /* skip hole */
+ while (file_buff->end() <= ptr->end &&
+ file_buffer_start != (my_off_t)-1)
+ file_buffer_start= file_buff->read_next();
+ write_begin= ptr->end;
+ ptr++;
+ }
+ else
+ write_begin= write_end;
+
+ if (write_end == file_buff->end())
+ file_buffer_start= file_buff->read_next(); /* shift the buffer */
+
+ }
+
+ if (mysql_file_sync(update_temp_file, MYF(MY_WME)) ||
+ mysql_file_close(update_temp_file, MYF(0)))
+ DBUG_RETURN(-1);
+
+ share->update_file_opened= FALSE;
+
+ if (share->tina_write_opened)
+ {
+ if (mysql_file_close(share->tina_write_filedes, MYF(0)))
+ DBUG_RETURN(-1);
+ /*
+ Mark that the writer fd is closed, so that init_tina_writer()
+ will reopen it later.
+ */
+ share->tina_write_opened= FALSE;
+ }
+
+ /*
+ Close opened fildes's. Then move updated file in place
+ of the old datafile.
+ */
+ if (mysql_file_close(data_file, MYF(0)) ||
+ mysql_file_rename(csv_key_file_data,
+ fn_format(updated_fname, share->table_name,
+ "", CSN_EXT,
+ MY_REPLACE_EXT | MY_UNPACK_FILENAME),
+ share->data_file_name, MYF(0)))
+ DBUG_RETURN(-1);
+
+ /* Open the file again */
+ if ((data_file= mysql_file_open(csv_key_file_data,
+ share->data_file_name,
+ O_RDONLY, MYF(MY_WME))) == -1)
+ DBUG_RETURN(my_errno ? my_errno : -1);
+ /*
+ As we reopened the data file, increase share->data_file_version
+ in order to force other threads waiting on a table lock and
+ have already opened the table to reopen the data file.
+ That makes the latest changes become visible to them.
+ Update local_data_file_version as no need to reopen it in the
+ current thread.
+ */
+ share->data_file_version++;
+ local_data_file_version= share->data_file_version;
+ /*
+ The datafile is consistent at this point and the write filedes is
+ closed, so nothing worrying will happen to it in case of a crash.
+ Here we record this fact to the meta-file.
+ */
+ (void)write_meta_file(share->meta_file, share->rows_recorded, FALSE);
+ /*
+ Update local_saved_data_file_length with the real length of the
+ data file.
+ */
+ local_saved_data_file_length= temp_file_length;
+ }
+
+ DBUG_RETURN(0);
+error:
+ mysql_file_close(update_temp_file, MYF(0));
+ share->update_file_opened= FALSE;
+ DBUG_RETURN(-1);
+}
+
+
+/*
+ Repair CSV table in the case, it is crashed.
+
+ SYNOPSIS
+ repair()
+ thd The thread, performing repair
+ check_opt The options for repair. We do not use it currently.
+
+ DESCRIPTION
+ If the file is empty, change # of rows in the file and complete recovery.
+ Otherwise, scan the table looking for bad rows. If none were found,
+ we mark file as a good one and return. If a bad row was encountered,
+ we truncate the datafile up to the last good row.
+
+ TODO: Make repair more clever - it should try to recover subsequent
+ rows (after the first bad one) as well.
+*/
+
+int ha_tina::repair(THD* thd, HA_CHECK_OPT* check_opt)
+{
+ char repaired_fname[FN_REFLEN];
+ uchar *buf;
+ File repair_file;
+ int rc;
+ ha_rows rows_repaired= 0;
+ my_off_t write_begin= 0, write_end;
+ DBUG_ENTER("ha_tina::repair");
+
+ /* empty file */
+ if (!share->saved_data_file_length)
+ {
+ share->rows_recorded= 0;
+ goto end;
+ }
+
+ /* Don't assert in field::val() functions */
+ table->use_all_columns();
+
+ /* position buffer to the start of the file */
+ if (init_data_file())
+ DBUG_RETURN(HA_ERR_CRASHED_ON_REPAIR);
+
+ if (!(buf= (uchar*) my_malloc(csv_key_memory_row, table->s->reclength,
+ MYF(MY_WME))))
+ DBUG_RETURN(HA_ERR_OUT_OF_MEM);
+ /*
+ Local_saved_data_file_length is initialized during the lock phase.
+ Sometimes this is not getting executed before ::repair (e.g. for
+ the log tables). We set it manually here.
+ */
+ local_saved_data_file_length= share->saved_data_file_length;
+ /* set current position to the beginning of the file */
+ current_position= next_position= 0;
+
+ /* Read the file row-by-row. If everything is ok, repair is not needed. */
+ thd_inc_error_row(thd);
+ while (!(rc= find_current_row(buf)))
+ {
+ thd_inc_error_row(thd);
+ rows_repaired++;
+ current_position= next_position;
+ }
+
+ free_root(&blobroot, MYF(0));
+
+ my_free(buf);
+
+ if (rc == HA_ERR_END_OF_FILE)
+ {
+ /*
+ All rows were read ok until end of file, the file does not need repair.
+ If rows_recorded != rows_repaired, we should update rows_recorded value
+ to the current amount of rows.
+ */
+ share->rows_recorded= rows_repaired;
+ goto end;
+ }
+
+ /*
+ Otherwise we've encountered a bad row => repair is needed.
+ Let us create a temporary file.
+ */
+ if ((repair_file= mysql_file_create(csv_key_file_update,
+ fn_format(repaired_fname,
+ share->table_name,
+ "", CSN_EXT,
+ MY_REPLACE_EXT|MY_UNPACK_FILENAME),
+ 0, O_RDWR | O_TRUNC, MYF(MY_WME))) < 0)
+ DBUG_RETURN(HA_ERR_CRASHED_ON_REPAIR);
+
+ file_buff->init_buff(data_file);
+
+
+ /* we just truncated the file up to the first bad row. update rows count. */
+ share->rows_recorded= rows_repaired;
+
+ /* write repaired file */
+ while (1)
+ {
+ write_end= MY_MIN(file_buff->end(), current_position);
+ if ((write_end - write_begin) &&
+ (mysql_file_write(repair_file, (uchar*)file_buff->ptr(),
+ (size_t) (write_end - write_begin), MYF(MY_WME+MY_NABP))))
+ DBUG_RETURN(-1);
+
+ write_begin= write_end;
+ if (write_end== current_position)
+ break;
+ else
+ file_buff->read_next(); /* shift the buffer */
+ }
+
+ /*
+ Close the files and rename repaired file to the datafile.
+ We have to close the files, as on Windows one cannot rename
+ a file, which descriptor is still open. EACCES will be returned
+ when trying to delete the "to"-file in mysql_file_rename().
+ */
+ if (share->tina_write_opened)
+ {
+ /*
+ Data file might be opened twice, on table opening stage and
+ during write_row execution. We need to close both instances
+ to satisfy Win.
+ */
+ if (mysql_file_close(share->tina_write_filedes, MYF(0)))
+ DBUG_RETURN(my_errno ? my_errno : -1);
+ share->tina_write_opened= FALSE;
+ }
+ mysql_file_close(data_file, MYF(0));
+ mysql_file_close(repair_file, MYF(0));
+ if (mysql_file_rename(csv_key_file_data,
+ repaired_fname, share->data_file_name, MYF(0)))
+ DBUG_RETURN(-1);
+
+ /* Open the file again, it should now be repaired */
+ if ((data_file= mysql_file_open(csv_key_file_data,
+ share->data_file_name, O_RDWR|O_APPEND,
+ MYF(MY_WME))) == -1)
+ DBUG_RETURN(my_errno ? my_errno : -1);
+
+ /* Set new file size. The file size will be updated by ::update_status() */
+ local_saved_data_file_length= (size_t) current_position;
+
+end:
+ share->crashed= FALSE;
+ DBUG_RETURN(HA_ADMIN_OK);
+}
+
+/*
+ DELETE without WHERE calls this
+*/
+
+int ha_tina::delete_all_rows()
+{
+ int rc;
+ DBUG_ENTER("ha_tina::delete_all_rows");
+
+ if (!records_is_known)
+ DBUG_RETURN(my_errno=HA_ERR_WRONG_COMMAND);
+
+ if (!share->tina_write_opened)
+ if (init_tina_writer())
+ DBUG_RETURN(-1);
+
+ /* Truncate the file to zero size */
+ rc= mysql_file_chsize(share->tina_write_filedes, 0, 0, MYF(MY_WME));
+
+ stats.records=0;
+ /* Update shared info */
+ mysql_mutex_lock(&share->mutex);
+ share->rows_recorded= 0;
+ mysql_mutex_unlock(&share->mutex);
+ local_saved_data_file_length= 0;
+ DBUG_RETURN(rc);
+}
+
+int ha_tina::external_lock(THD *thd __attribute__((unused)), int lock_type)
+{
+ if (lock_type==F_UNLCK && curr_lock_type == F_WRLCK)
+ update_status();
+ curr_lock_type= lock_type;
+ return 0;
+}
+
+/*
+ Called by the database to lock the table. Keep in mind that this
+ is an internal lock.
+*/
+THR_LOCK_DATA **ha_tina::store_lock(THD *thd,
+ THR_LOCK_DATA **to,
+ enum thr_lock_type lock_type)
+{
+ if (lock_type != TL_IGNORE && lock.type == TL_UNLOCK)
+ lock.type=lock_type;
+ *to++= &lock;
+ return to;
+}
+
+/*
+ Create a table. You do not want to leave the table open after a call to
+ this (the database will call ::open() if it needs to).
+*/
+
+int ha_tina::create(const char *name, TABLE *table_arg,
+ HA_CREATE_INFO *create_info)
+{
+ char name_buff[FN_REFLEN];
+ File create_file;
+ DBUG_ENTER("ha_tina::create");
+
+ /*
+ check columns
+ */
+ for (Field **field= table_arg->s->field; *field; field++)
+ {
+ if ((*field)->real_maybe_null())
+ {
+ my_error(ER_CHECK_NOT_IMPLEMENTED, MYF(0), "nullable columns");
+ DBUG_RETURN(HA_ERR_UNSUPPORTED);
+ }
+ }
+
+
+ if ((create_file= mysql_file_create(csv_key_file_metadata,
+ fn_format(name_buff, name, "", CSM_EXT,
+ MY_REPLACE_EXT|MY_UNPACK_FILENAME),
+ 0, O_RDWR | O_TRUNC, MYF(MY_WME))) < 0)
+ DBUG_RETURN(-1);
+
+ write_meta_file(create_file, 0, FALSE);
+ mysql_file_close(create_file, MYF(0));
+
+ if ((create_file= mysql_file_create(csv_key_file_data,
+ fn_format(name_buff, name, "", CSV_EXT,
+ MY_REPLACE_EXT|MY_UNPACK_FILENAME),
+ 0, O_RDWR | O_TRUNC, MYF(MY_WME))) < 0)
+ DBUG_RETURN(-1);
+
+ mysql_file_close(create_file, MYF(0));
+
+ DBUG_RETURN(0);
+}
+
+int ha_tina::check(THD* thd, HA_CHECK_OPT* check_opt)
+{
+ int rc= 0;
+ uchar *buf;
+ const char *old_proc_info;
+ ha_rows count= share->rows_recorded;
+ DBUG_ENTER("ha_tina::check");
+
+ old_proc_info= thd_proc_info(thd, "Checking table");
+
+ /* position buffer to the start of the file */
+ if (init_data_file())
+ DBUG_RETURN(HA_ERR_CRASHED);
+
+ if (!(buf= (uchar*) my_malloc(csv_key_memory_row, table->s->reclength,
+ MYF(MY_WME))))
+ DBUG_RETURN(HA_ERR_OUT_OF_MEM);
+
+ /*
+ Local_saved_data_file_length is initialized during the lock phase.
+ Check does not use store_lock in certain cases. So, we set it
+ manually here.
+ */
+ local_saved_data_file_length= share->saved_data_file_length;
+ /* set current position to the beginning of the file */
+ current_position= next_position= 0;
+
+ /* Read the file row-by-row. If everything is ok, repair is not needed. */
+ while (!(rc= find_current_row(buf)))
+ {
+ thd_inc_error_row(thd);
+ count--;
+ current_position= next_position;
+ }
+
+ free_root(&blobroot, MYF(0));
+
+ my_free(buf);
+ thd_proc_info(thd, old_proc_info);
+
+ if ((rc != HA_ERR_END_OF_FILE) || count)
+ {
+ share->crashed= TRUE;
+ DBUG_RETURN(HA_ADMIN_CORRUPT);
+ }
+
+ DBUG_RETURN(HA_ADMIN_OK);
+}
+
+
+int ha_tina::reset(void)
+{
+ free_root(&blobroot, MYF(0));
+ return 0;
+}
+
+
+bool ha_tina::check_if_incompatible_data(HA_CREATE_INFO *info_arg,
+ uint table_changes)
+{
+ if (info_arg->option_struct->ietf_quotes !=
+ table_share->option_struct->ietf_quotes)
+ return COMPATIBLE_DATA_NO;
+
+ return COMPATIBLE_DATA_YES;
+}
+
+struct st_mysql_storage_engine csv_storage_engine=
+{ MYSQL_HANDLERTON_INTERFACE_VERSION };
+
+maria_declare_plugin(csv)
+{
+ MYSQL_STORAGE_ENGINE_PLUGIN,
+ &csv_storage_engine,
+ "CSV",
+ "Brian Aker, MySQL AB",
+ "Stores tables as CSV files",
+ PLUGIN_LICENSE_GPL,
+ tina_init_func, /* Plugin Init */
+ tina_done_func, /* Plugin Deinit */
+ 0x0100 /* 1.0 */,
+ NULL, /* status variables */
+ NULL, /* system variables */
+ "1.0", /* string version */
+ MariaDB_PLUGIN_MATURITY_STABLE /* maturity */
+}
+maria_declare_plugin_end;
diff --git a/storage/csv/ha_tina.h b/storage/csv/ha_tina.h
new file mode 100644
index 00000000..04318344
--- /dev/null
+++ b/storage/csv/ha_tina.h
@@ -0,0 +1,180 @@
+/* Copyright (c) 2003, 2011, Oracle and/or its affiliates. All rights reserved.
+
+ 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; version 2 of the License.
+
+ 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., 51 Franklin St, Fifth Floor, Boston, MA 02110-1335 USA */
+
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <my_dir.h>
+#include "transparent_file.h"
+
+#define DEFAULT_CHAIN_LENGTH 512
+/*
+ Version for file format.
+ 1 - Initial Version. That is, the version when the metafile was introduced.
+*/
+
+#define TINA_VERSION 1
+
+typedef struct st_tina_share {
+ char *table_name;
+ char data_file_name[FN_REFLEN];
+ uint table_name_length, use_count;
+ /*
+ Below flag is needed to make log tables work with concurrent insert.
+ For more details see comment to ha_tina::update_status.
+ */
+ my_bool is_log_table;
+ /*
+ Here we save the length of the file for readers. This is updated by
+ inserts, updates and deletes. The var is initialized along with the
+ share initialization.
+ */
+ my_off_t saved_data_file_length;
+ mysql_mutex_t mutex;
+ THR_LOCK lock;
+ bool update_file_opened;
+ bool tina_write_opened;
+ File meta_file; /* Meta file we use */
+ File tina_write_filedes; /* File handler for readers */
+ bool crashed; /* Meta file is crashed */
+ ha_rows rows_recorded; /* Number of rows in tables */
+ uint data_file_version; /* Version of the data file used */
+} TINA_SHARE;
+
+struct tina_set {
+ my_off_t begin;
+ my_off_t end;
+};
+
+class ha_tina final : public handler
+{
+ THR_LOCK_DATA lock; /* MySQL lock */
+ TINA_SHARE *share; /* Shared lock info */
+ my_off_t current_position; /* Current position in the file during a file scan */
+ my_off_t next_position; /* Next position in the file scan */
+ my_off_t local_saved_data_file_length; /* save position for reads */
+ my_off_t temp_file_length;
+ uchar byte_buffer[IO_SIZE];
+ Transparent_file *file_buff;
+ File data_file; /* File handler for readers */
+ File update_temp_file;
+ String buffer;
+ /*
+ The chain contains "holes" in the file, occurred because of
+ deletes/updates. It is used in rnd_end() to get rid of them
+ in the end of the query.
+ */
+ tina_set chain_buffer[DEFAULT_CHAIN_LENGTH];
+ tina_set *chain;
+ tina_set *chain_ptr;
+ uchar chain_alloced;
+ uint32 chain_size;
+ uint local_data_file_version; /* Saved version of the data file used */
+ bool records_is_known, found_end_of_file;
+ MEM_ROOT blobroot;
+
+private:
+ int curr_lock_type;
+
+ bool get_write_pos(my_off_t *end_pos, tina_set *closest_hole);
+ int open_update_temp_file_if_needed();
+ int init_tina_writer();
+ int init_data_file();
+
+public:
+ ha_tina(handlerton *hton, TABLE_SHARE *table_arg);
+ ~ha_tina()
+ {
+ if (chain_alloced)
+ my_free(chain);
+ if (file_buff)
+ delete file_buff;
+ free_root(&blobroot, MYF(0));
+ }
+ const char *index_type(uint inx) { return "NONE"; }
+ ulonglong table_flags() const
+ {
+ return (HA_NO_TRANSACTIONS | HA_REC_NOT_IN_SEQ | HA_NO_AUTO_INCREMENT |
+ HA_BINLOG_ROW_CAPABLE | HA_BINLOG_STMT_CAPABLE | HA_CAN_EXPORT |
+ HA_CAN_REPAIR | HA_SLOW_RND_POS);
+ }
+ ulong index_flags(uint idx, uint part, bool all_parts) const
+ {
+ /*
+ We will never have indexes so this will never be called(AKA we return
+ zero)
+ */
+ return 0;
+ }
+ uint max_record_length() const { return HA_MAX_REC_LENGTH; }
+ uint max_keys() const { return 0; }
+ uint max_key_parts() const { return 0; }
+ uint max_key_length() const { return 0; }
+ /*
+ Called in test_quick_select to determine if indexes should be used.
+ */
+ virtual double scan_time() { return (double) (stats.records+stats.deleted) / 20.0+10; }
+ /* The next method will never be called */
+ virtual bool fast_key_read() { return 1;}
+ /*
+ TODO: return actual upper bound of number of records in the table.
+ (e.g. save number of records seen on full table scan and/or use file size
+ as upper bound)
+ */
+ ha_rows estimate_rows_upper_bound() { return HA_POS_ERROR; }
+
+ int open(const char *name, int mode, uint open_options);
+ int close(void);
+ int write_row(const uchar * buf);
+ int update_row(const uchar * old_data, const uchar * new_data);
+ int delete_row(const uchar * buf);
+ int rnd_init(bool scan=1);
+ int rnd_next(uchar *buf);
+ int rnd_pos(uchar * buf, uchar *pos);
+ bool check_and_repair(THD *thd);
+ int check(THD* thd, HA_CHECK_OPT* check_opt);
+ bool is_crashed() const;
+ int rnd_end();
+ int repair(THD* thd, HA_CHECK_OPT* check_opt);
+ /* This is required for SQL layer to know that we support autorepair */
+ bool auto_repair(int error) const
+ { return error == HA_ERR_CRASHED_ON_USAGE; }
+ bool auto_repair() const { return 1; }
+ void position(const uchar *record);
+ int info(uint);
+ int reset();
+ int extra(enum ha_extra_function operation);
+ int delete_all_rows(void);
+ int create(const char *name, TABLE *form, HA_CREATE_INFO *create_info);
+ bool check_if_incompatible_data(HA_CREATE_INFO *info,
+ uint table_changes);
+
+ int external_lock(THD *thd, int lock_type);
+
+ THR_LOCK_DATA **store_lock(THD *thd, THR_LOCK_DATA **to,
+ enum thr_lock_type lock_type);
+
+ /*
+ These functions used to get/update status of the handler.
+ Needed to enable concurrent inserts.
+ */
+ void get_status();
+ void update_status();
+
+ /* The following methods were added just for TINA */
+ int encode_quote(const uchar *buf);
+ int find_current_row(uchar *buf);
+ int chain_append();
+};
+
diff --git a/storage/csv/transparent_file.cc b/storage/csv/transparent_file.cc
new file mode 100644
index 00000000..443e61d0
--- /dev/null
+++ b/storage/csv/transparent_file.cc
@@ -0,0 +1,109 @@
+/* Copyright (c) 2003, 2010, Oracle and/or its affiliates. All rights reserved.
+
+ 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; version 2 of the License.
+
+ 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., 51 Franklin St, Fifth Floor, Boston, MA 02110-1335 USA */
+
+#ifdef USE_PRAGMA_IMPLEMENTATION
+#pragma implementation // gcc: Class implementation
+#endif
+
+#include <my_global.h>
+#include "sql_priv.h"
+#include <mysql/psi/mysql_file.h>
+#include "transparent_file.h"
+#include "my_sys.h" // MY_WME, MY_ALLOW_ZERO_PTR, MY_SEEK_SET
+
+PSI_memory_key csv_key_memory_Transparent_file;
+
+Transparent_file::Transparent_file() : lower_bound(0), buff_size(IO_SIZE)
+{
+ buff= (uchar *) my_malloc(csv_key_memory_Transparent_file,
+ buff_size*sizeof(uchar), MYF(MY_WME));
+}
+
+Transparent_file::~Transparent_file()
+{
+ my_free(buff);
+}
+
+void Transparent_file::init_buff(File filedes_arg)
+{
+ filedes= filedes_arg;
+ /* read the beginning of the file */
+ lower_bound= 0;
+ mysql_file_seek(filedes, 0, MY_SEEK_SET, MYF(0));
+ if (filedes && buff)
+ upper_bound= mysql_file_read(filedes, buff, buff_size, MYF(0));
+}
+
+uchar *Transparent_file::ptr()
+{
+ return buff;
+}
+
+my_off_t Transparent_file::start()
+{
+ return lower_bound;
+}
+
+my_off_t Transparent_file::end()
+{
+ return upper_bound;
+}
+
+my_off_t Transparent_file::read_next()
+{
+ size_t bytes_read;
+
+ /*
+ No need to seek here, as the file managed by Transparent_file class
+ always points to upper_bound byte
+ */
+ if ((bytes_read= mysql_file_read(filedes, buff, buff_size, MYF(0)))
+ == MY_FILE_ERROR)
+ return (my_off_t) -1;
+
+ /* end of file */
+ if (!bytes_read)
+ return (my_off_t) -1;
+
+ lower_bound= upper_bound;
+ upper_bound+= bytes_read;
+
+ return lower_bound;
+}
+
+
+char Transparent_file::get_value(my_off_t offset)
+{
+ size_t bytes_read;
+
+ /* check boundaries */
+ if ((lower_bound <= offset) && (((my_off_t) offset) < upper_bound))
+ return buff[offset - lower_bound];
+
+ mysql_file_seek(filedes, offset, MY_SEEK_SET, MYF(0));
+ /* read appropriate portion of the file */
+ if ((bytes_read= mysql_file_read(filedes, buff, buff_size,
+ MYF(0))) == MY_FILE_ERROR)
+ return 0;
+
+ lower_bound= offset;
+ upper_bound= lower_bound + bytes_read;
+
+ /* end of file */
+ if (upper_bound == (my_off_t) offset)
+ return 0;
+
+ return buff[0];
+}
diff --git a/storage/csv/transparent_file.h b/storage/csv/transparent_file.h
new file mode 100644
index 00000000..545643d0
--- /dev/null
+++ b/storage/csv/transparent_file.h
@@ -0,0 +1,43 @@
+/* Copyright (c) 2003, 2007 MySQL AB, 2009 Sun Microsystems, Inc.
+ Use is subject to license terms.
+
+ 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; version 2 of the License.
+
+ 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., 51 Franklin St, Fifth Floor, Boston, MA 02110-1335 USA */
+
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <my_dir.h>
+
+extern PSI_memory_key csv_key_memory_Transparent_file;
+
+class Transparent_file
+{
+ File filedes;
+ uchar *buff; /* in-memory window to the file or mmaped area */
+ /* current window sizes */
+ my_off_t lower_bound;
+ my_off_t upper_bound;
+ uint buff_size;
+
+public:
+
+ Transparent_file();
+ ~Transparent_file();
+
+ void init_buff(File filedes_arg);
+ uchar *ptr();
+ my_off_t start();
+ my_off_t end();
+ char get_value (my_off_t offset);
+ my_off_t read_next();
+};