instiki/vendor/plugins/sqlite3-ruby/sqlite3/pragmas.rb
Jacques Distler bceb1864df Fixes
Fix Session CookieOverflow bug when rescuing an InstikiValidation error.
Fix some random things which will cause problems with Ruby 1.9. (Plenty
more where those came from.)
2008-11-05 22:24:14 -06:00

301 lines
8.9 KiB
Ruby

#--
# =============================================================================
# Copyright (c) 2004, Jamis Buck (jgb3@email.byu.edu)
# All rights reserved.
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions are met:
#
# * Redistributions of source code must retain the above copyright notice,
# this list of conditions and the following disclaimer.
#
# * Redistributions in binary form must reproduce the above copyright
# notice, this list of conditions and the following disclaimer in the
# documentation and/or other materials provided with the distribution.
#
# * The names of its contributors may not be used to endorse or promote
# products derived from this software without specific prior written
# permission.
#
# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
# AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
# DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE
# FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
# SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
# CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
# OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
# =============================================================================
#++
require 'sqlite3/errors'
module SQLite3
# This module is intended for inclusion solely by the Database class. It
# defines convenience methods for the various pragmas supported by SQLite3.
#
# For a detailed description of these pragmas, see the SQLite3 documentation
# at http://sqlite.org/pragma.html.
module Pragmas
# Returns +true+ or +false+ depending on the value of the named pragma.
def get_boolean_pragma( name )
get_first_value( "PRAGMA #{name}" ) != "0"
end
private :get_boolean_pragma
# Sets the given pragma to the given boolean value. The value itself
# may be +true+ or +false+, or any other commonly used string or
# integer that represents truth.
def set_boolean_pragma( name, mode )
case mode
when String
case mode.downcase
when "on", "yes", "true", "y", "t" then mode = "'ON'"
when "off", "no", "false", "n", "f" then mode = "'OFF'"
else
raise Exception,
"unrecognized pragma parameter #{mode.inspect}"
end
when true, 1
mode = "ON"
when false, 0, nil
mode = "OFF"
else
raise Exception,
"unrecognized pragma parameter #{mode.inspect}"
end
execute( "PRAGMA #{name}=#{mode}" )
end
private :set_boolean_pragma
# Requests the given pragma (and parameters), and if the block is given,
# each row of the result set will be yielded to it. Otherwise, the results
# are returned as an array.
def get_query_pragma( name, *parms, &block ) # :yields: row
if parms.empty?
execute( "PRAGMA #{name}", &block )
else
args = "'" + parms.join("','") + "'"
execute( "PRAGMA #{name}( #{args} )", &block )
end
end
private :get_query_pragma
# Return the value of the given pragma.
def get_enum_pragma( name )
get_first_value( "PRAGMA #{name}" )
end
private :get_enum_pragma
# Set the value of the given pragma to +mode+. The +mode+ parameter must
# conform to one of the values in the given +enum+ array. Each entry in
# the array is another array comprised of elements in the enumeration that
# have duplicate values. See #synchronous, #default_synchronous,
# #temp_store, and #default_temp_store for usage examples.
def set_enum_pragma( name, mode, enums )
match = enums.find { |p| p.find { |i| i.to_s.downcase == mode.to_s.downcase } }
raise Exception,
"unrecognized #{name} #{mode.inspect}" unless match
execute( "PRAGMA #{name}='#{match.first.upcase}'" )
end
private :set_enum_pragma
# Returns the value of the given pragma as an integer.
def get_int_pragma( name )
get_first_value( "PRAGMA #{name}" ).to_i
end
private :get_int_pragma
# Set the value of the given pragma to the integer value of the +value+
# parameter.
def set_int_pragma( name, value )
execute( "PRAGMA #{name}=#{value.to_i}" )
end
private :set_int_pragma
# The enumeration of valid synchronous modes.
SYNCHRONOUS_MODES = [ [ 'full', 2 ], [ 'normal', 1 ], [ 'off', 0 ] ]
# The enumeration of valid temp store modes.
TEMP_STORE_MODES = [ [ 'default', 0 ], [ 'file', 1 ], [ 'memory', 2 ] ]
# Does an integrity check on the database. If the check fails, a
# SQLite3::Exception will be raised. Otherwise it
# returns silently.
def integrity_check
execute( "PRAGMA integrity_check" ) do |row|
raise Exception, row[0] if row[0] != "ok"
end
end
def auto_vacuum
get_boolean_pragma "auto_vacuum"
end
def auto_vacuum=( mode )
set_boolean_pragma "auto_vacuum", mode
end
def schema_cookie
get_int_pragma "schema_cookie"
end
def schema_cookie=( cookie )
set_int_pragma "schema_cookie", cookie
end
def user_cookie
get_int_pragma "user_cookie"
end
def user_cookie=( cookie )
set_int_pragma "user_cookie", cookie
end
def cache_size
get_int_pragma "cache_size"
end
def cache_size=( size )
set_int_pragma "cache_size", size
end
def default_cache_size
get_int_pragma "default_cache_size"
end
def default_cache_size=( size )
set_int_pragma "default_cache_size", size
end
def default_synchronous
get_enum_pragma "default_synchronous"
end
def default_synchronous=( mode )
set_enum_pragma "default_synchronous", mode, SYNCHRONOUS_MODES
end
def synchronous
get_enum_pragma "synchronous"
end
def synchronous=( mode )
set_enum_pragma "synchronous", mode, SYNCHRONOUS_MODES
end
def default_temp_store
get_enum_pragma "default_temp_store"
end
def default_temp_store=( mode )
set_enum_pragma "default_temp_store", mode, TEMP_STORE_MODES
end
def temp_store
get_enum_pragma "temp_store"
end
def temp_store=( mode )
set_enum_pragma "temp_store", mode, TEMP_STORE_MODES
end
def full_column_names
get_boolean_pragma "full_column_names"
end
def full_column_names=( mode )
set_boolean_pragma "full_column_names", mode
end
def parser_trace
get_boolean_pragma "parser_trace"
end
def parser_trace=( mode )
set_boolean_pragma "parser_trace", mode
end
def vdbe_trace
get_boolean_pragma "vdbe_trace"
end
def vdbe_trace=( mode )
set_boolean_pragma "vdbe_trace", mode
end
def database_list( &block ) # :yields: row
get_query_pragma "database_list", &block
end
def foreign_key_list( table, &block ) # :yields: row
get_query_pragma "foreign_key_list", table, &block
end
def index_info( index, &block ) # :yields: row
get_query_pragma "index_info", index, &block
end
def index_list( table, &block ) # :yields: row
get_query_pragma "index_list", table, &block
end
def table_info( table, &block ) # :yields: row
columns, *rows = execute2("PRAGMA table_info(#{table})")
needs_tweak_default = version_compare(driver.libversion, "3.3.7") > 0
result = [] unless block_given?
rows.each do |row|
new_row = {}
columns.each_with_index do |name, index|
new_row[name] = row[index]
end
tweak_default(new_row) if needs_tweak_default
if block_given?
yield new_row
else
result << new_row
end
end
result
end
private
# Compares two version strings
def version_compare(v1, v2)
v1 = v1.split(".").map { |i| i.to_i }
v2 = v2.split(".").map { |i| i.to_i }
parts = [v1.length, v2.length].max
v1.push 0 while v1.length < parts
v2.push 0 while v2.length < parts
v1.zip(v2).each do |a,b|
return -1 if a < b
return 1 if a > b
end
return 0
end
# Since SQLite 3.3.8, the table_info pragma has returned the default
# value of the row as a quoted SQL value. This method essentially
# unquotes those values.
def tweak_default(hash)
case hash["dflt_value"]
when /^null$/i then
hash["dflt_value"] = nil
when /^'(.*)'$/
hash["dflt_value"] = $1.gsub(/''/, "'")
end
end
end
end