PHP userland backwards compatibility layer that emulates PHP 5.5+ core functions.

βŒˆβŒ‹ βŽ‡ branch:  upgrade.php


All Files in doc/

Files in directory /doc in any check-in

  • devtools
  • tests1all
  • tests2filter
  • gettext.txt
  • README
  • runtest
  • updoc


PHP downwards compatibility functions
-------------------------------------
The "upgrade.php" package implements features and functions from
newer PHP versions. It defines them as pure PHP code. Functions
get defined dynamically, at runtime. All emulated functions use
names identical to the original implementation. But won't perturb
if the native functions exist.

So this is really a drop-in replacement. It allows you to use most
PHP features regardless of the current PHP interpreter. You just
have to include() this single script to remove any backward
compatibility woes.
This allows relying on the newer, more powerful PHP functions. Use
and retyping of workarounds gets superfluous.


this is useful:

- for open source distributions
- if your own providers PHP version is immemorial
- you want to test new functions, but not install a new PHP ver
- usage of gettext/bcmath/ftp/... extension would be nice in your
  project, but may not be available on all target web servers
- if some other PHP project has a unmet dependency on your server


when it cannot help:

- extended PHP5 object-orientation semantics can't be emulated
- function signatures in newer PHP versions also sometimes change,
  and these cannot be overriden or extended by upgradephp
- doesn't help against amateur providers safe_mode
- compatibility with PHP<4.0 cannot be reached


other things to note:

- as already said, speed won't suffer on up-to-date servers, because
  functions are only emulated/defined if they are missing
- some functions are just simple stubs
- emulated functions are mostly slower than the native would be,
  of course
- not all PHP errors are exactly mimicked,
  -> upgradephp leaves this often to parent functions (e.g. fopen)
  -> and you probably test for errors on native PHP setups anyhow
     (no practical need to have that in emulation mode)
- memory shouldn't increase significantly, because if(func_exists)
  "interpretes away" most code 


Remember that native functions will be used whereever available,
this emulation just helps getting scripts run on aging PHP versions.



      PEAR::PHP_Compat
      ----------------
      Alternatively to the "upgradephp" package, you could also give
      the PEAR package "PHP_Compat" (by Aidan Lister & Co.) from
      [http://pear.php.net/] a try. It comes under the LGPL license
      and contains more PHP4.0 emulation (what's not targetted anymore
      in upgrade.php).
      You could even use it in conjunction with upgrade.php

      Note: no code from PHP_Compat has been reused here (this is more
      a license thing, than NIH syndrome).



Usage
-----
Simply include("upgrade.php"); in any of your scripts, if you want
to rely on some PHP5.5 functions.

   include("upgrade.php");

You could additionally check the PHP_VERSION, and only include the
emulation wrapper if you depend on features from a certain PHP
interpreter release:

  <?example
     if (PHP_VERSION < "5.4.0") { include(".../upgrade.php"); }
  ?>

Currently following functions can be emulated:
· array_column
· json_last_error_msg
· boolval
· json_encode
· json_decode
· strptime
· gzdecode
· htmlspecialchars_decode
· fputcsv
· ob_get_headers
· xmlentities
· stripos
· strripos
· str_ireplace
· get_headers
· headers_list
· fprintf
· vfprintf
· str_split
· http_build_query
· convert_uuencode
· convert_uudecode
· scandir
· idate
· time_nanosleep
· strpbrk
· php_real_logo_guid
· php_egg_logo_guid
· get_declared_interfaces
· array_combine
· array_walk_recursive
· substr_compare
· spl_classes
· class_parents
· session_commit
· dns_check_record
· dns_get_mx
· setrawcookie
· file_put_contents
· count_recursive
· file_get_contents
· fnmatch
· glob
· array_key_exists
· array_intersect_assoc
· array_diff_assoc
· html_entity_decode
· str_word_count
· str_shuffle
· get_include_path
· set_include_path
· restore_include_path
· str_rot13
· array_change_key_case
· array_fill
· array_chunk
· md5_file
· is_a
· fmod
· floatval
· is_infinite
· is_nan
· is_finite
· var_export
· strcoll
· diskfreespace
· disktotalspace
· vprintf
· vsprintf
· import_request_variables
· hypot
· log1p
· expm1
· sinh
· cosh
· tanh
· asinh
· acosh
· atanh
· mhash
· mhash_count
· mhash_get_hash_name
· mhash_get_block_size
· array_udiff_uassoc
· array_udiff_assoc
· array_diff_uassoc
· array_udiff
· array_uintersect_uassoc
· array_uintersect_assoc
· array_uintersect
· array_intersect_uassoc
· dc___exec
· bcscale
· bcadd
· bcsub
· bcmul
· bcdiv
· bcmod
· bcpow
· bcpowmod
· bcsqrt
· bccomp
· bc___scaledown
· gettext
· gettext___plural_guess
· ngettext
· dngettext
· dcngettext
· dcgettext
· dgettext
· textdomain
· bindtextdomain
· gettext___load_mo
· gettext___load_po
· bind_textdomain_codeset
· _
· mime_content_type
· image_type_to_mime_type
· image_type_to_extension
· exif_imagetype
· array_filter
· array_map
· is_callable
· array_search
· array_reduce
· is_scalar
· localeconv
· call_user_func_array
· call_user_method_array
· array_sum
· constant
· is_null
· pathinfo
· escapeshellarg
· is_uploaded_file
· move_uploaded_file
· strncasecmp
· wordwrap
· php_uname
· php_sapi_name
· posix_mkfifo
· posix_getcwd
· posix_kill
· posix_uname
· ctype_alnum
· ctype_alpha
· ctype_digit
· ctype_xdigit
· ctype_cntrl
· ctype_space
· ctype_upper
· ctype_lower
· ctype_graph
· ctype_punct
· ctype_print
· odbc_connect
· odbc_pconnect
· odbc_close
· odbc_exec
· odbc_do
· odbc_prepare
· odbc_execute
· odbc_fetch_array
· odbc_fetch_row
· odbc_fetch_object
· odbc_fetch_into
· odbc_free_result
· odbc_next_result
· odbc_num_fields
· odbc_num_rows


Redistribution
--------------
You are encouraged to distribute "upgrade.php" together with
other / your projects. That's also why it was released as Public
Domain (=compatible to ALL open source licenses, including the
GNU GPL and LGPL).

You could load it automatically then using the PHP_VERSION check.
Or simply leave this to your users if they use an older PHP version.
A note often suffices.

Of course you might want to distribute only "upgrade.php" and any
required ext/ module. Just purge the rest (dtools/ and contrib/ or
this README), because they probably make little sense distributed
alongside elsewhere.

It is also safe to extract a few function bodies/definitions out of
upgrade.php to make a shorter version (load only the needed funcs).
But you should keep the "if (function_exists(...))" wrapper code
preferrably.
PHP_Compat however might make a better source if you really need
just one or two functions.


Omissions
---------
A few PHP features are specifically NOT implemented, and so still
had to be taken care of in your scripts:

· predefined STDIN, STDOUT and STDERR constants
· UPLOAD_ERR_* constants (introduced with 4.2, officially 4.3)
· ob_* (eventually possible)
· ini_get_all (ingenious trick in PHP_Compat)

Some of these functions and other esoteric code is implemented
in the ext/ scripts:


ext/
----
The ext/ subdirectory in here provides a few more or less useful
emulations for various PHP extensions or function groups.

· "ext/php40array" provides a few exotic array diff functions (for
  associative arrays and for using multiple callback functions)

· "ext/exotic" contains some rarely needed functions, which have
  been removed from the main file for that and other reasons

· "ext/bcmath" provides the mathematical functions with arbitrary
  precision on Unix systems, but emulation also works on top of
  GMP or big_int

· "ext/dba" allows you to use scripts written for the dba module,
  if your interpreter only has dbm_*() functions; but only provides
  the minimum functionality

· "ext/ftp" emulates the ftp extension using only the bare socket
  and networking functions (should work anywhere), even has some
  features not found in the original

· "ext/gettext" simulates most of what gettext/libintl provides, and
  seems to read .mo data files correctly - plural support is however
  weak. There is also support for .po files, but since the libintl
  and original gettext functions don't normally read this, that's a
  useless feature (just for fun). You save 2K by ripping it out.

· "ext/mime" simulates the mime_content_type() function, either by
  accessing PECL::fileinfo or reading and evaluating the magic.mime
  database itself (likely slower and a bit unclean of course)

Other snippets in ext/ are probably incomplete or just TODO stubs.


doc/devtools/
-------------
Please run the "updoc" script once to update your PHP manual, if you
are planning to use the upgrade.php script. It adds notes to version
compatibility strings on each page, when an upgradephp equivalent
exists.

· The "dtools/updoc" commandline script updates your local PHP
  documentation to carry hints about emulated functions. It'll simply
  add a small "EMU" on top of the supported functions` description
  pages (in the line typically listing the PHP versions).


The other cmdline scripts are used for developing upgrade.php:

· "cmpversion" was used to check for added functions between
   different PHP interpreter versions, purely a development script.

· "dtools/doctests" greps your local PHP manual for function use
  examples, and executes them with the given PHP interpreter and
  the "upgrade.php" script loaded of course. This way you get live
  tests.

· "dtools/compact" creates a collapsed version of the upgrade.php
  script (saved into contrib/)



doc/tests*
----------
Contains stupidly short scripts, that have been used to compare
behaviour of the original functions to that of the emulated ones.

The tests now can be run using PEARs RunTest class. (But not all
have been updated or proof-checked.)



ext/contrib/
------------
Holds a few library scripts, that will later be reworked to mimick
other new PHP extensions.

· "contrib/http" can be used to contact Web form scripts, or PHP
  code utilizing "ext/phprequest" more efficiently. It especially
  supports content-coding as per RFC2616 (HTTP standard) for saving
  a lot of bandwidth and getting answers faster.

· "contrib/hiddenerrors" shows a nice way to hide all disturbing
  error messages from users, but keeping them available for
  development. It is especially useful, when premature _NOTICEs or
  _WARNINGs could garbage (XML or binary) output or if this could
  prevent sending any further/required HTTP headers().

· "contrib/fix.php" fights magic_quotes and register_globals
  (though here it's often better to let users of outdated PHP setups
  run into the open knife, or die() with an error message)

· "contrib/phprequest" enables your PHP interpreter to receive HTTP
  requests with "application/vnd.php.serialized" encoding (even
  compressed) instead of the older "multipart/form-data" and the
  more simple "application/x-www-form-urlencoded" var post formats;
  this is faster and type-safe if you control both ends of the wire;
  see "contrib/README.http" for hints about the upcoming "PHP-RPC"

· "contrib/exceptions" provide a scheme for PHP4-compatible
  exception management using simple wrapper calls and agreements

Please also have a peek into the README files accompaning the script
snippets distributed in this directory.



Other Notes
-----------
· This script doesn't reside in any CVS/SVN reposititory currently
  because it is considered a too minor and small project.

· The project homepage is <http://upgradephp.berlios.de/> but see
  also <http://freshmeat.net/projects/upgradephp> for any update
  notifications.



License
-------
Almost all in here is Public Domain. There are no restrictions on how
or where you could use it. You may redistribute it under any license
as you wish, and you don't need to tell anyone where you got it from.
It has absolutely no impact on the rest of YOUR project; you are free
to include it as if you had written it yourself.

You could prepend the license preamble (GNU GPL, LGPL, BSD, MPL, MSFT
EULA, PHP, CDDL, Artistic, ...) of your choice if you want to.

Exceptions are the doc/tests* and doc/runtest scripts. Those are under
the PHP license, taken from PEAR, PECL or PHP.

The "ext/pdo.php" class is from Andrea Giammarchi and under the PHP
License as well. Also check out http://xpdo.org/ - the origin.


Author
------
The current maintainer can be contacted under <milky*users·sf·net>

Please drop me a line, regarding omissions, bugs, contributing a few
bytes...



ChangeLog
---------

v19
  - Adds new PHP5.5 functions: array_column(), json_last_error_msg(),
    boolval()
  - Ships with password_compat[MITL] from Anthony Ferrara, which add
    password_hash() and password_verify() from PHP5.5
  - Minor additions to json_encode and json_decode
  - Introduces ext/contrib/pdo_mysql.php, wrapper functions for PDO,
    that mimick the signature of mysql_* functions with a pdo_* prefix.

v18
  - Anthon Pang contributed mysqli_set_charset() and E_DEPRECATED const
  - Also contrib/safe_serialize and unserialize() implementations by Anthon
  - TMPDIR support for sys_get_temp_dir()
  - gzdecode is now an official PHP 5.4 function.
  - hex2bin
  - session_status
  - zlib_encode / zlib_decode
  - http_redirect, http_response_code, http_send_content_type
  - get_declared_traits (stub), class_uses (stub), get_declared_traits (stub)
  - json_encode: JSON_HEX_AMP, JSON_HEX_TAG, JSON_HEX_APOS, JSON_HEX_QUOT,
    (5.3.3 addition) JSON_NUMERIC_CHECK,
    (5.4.0 addition) JSON_PRETTY_PRINT, JSON_UNESCAPED_SLASHES
    and JSON_UNESCAPED_UNICODE.
  - json_decode: added flag JSON_BIGINT_AS_STRING, JSON_OBJECT_AS_ARRAY,
    and the non-standard JSON_PARSE_JAVASCRIPT
  - basic basic json_last_error() function

v17
  - new emulation of pspell extension using cmdline tool
  - escaping fixed in json_encode(), ignores utf-8 now
  - a few php 5.2 array functions added
  - str_getcsv, parse_ini_string, quoted_printable_encode
  - inet_pton, inet_ntop, 
  - fixes to sys_get_tmp_dir, error_get_last, property_exists, uuencode,
    get_headers, vprintf, import_request_variables
  - test-up script is now used for executing documentation tests,
    old PEAR test script is nonfunctional

v16
  - json_decode() array-conversion fix by Gerhard (tinned-software.net)
  - object-oriented input $_REQUEST filter wrapper in contrib/
  - some old code moved to contrib/archive/

v15
  - moved to phpDoc comment style,
    but not all emulated functions carry @param lists
  - tarball directories restructured
  - ext/filter ...
  - json_decode now decodes \uXXXX unicode references
  - include the PDO emulation classes of Andrea Giammarchi (under PHP License)

v14
  - initial comment restructuring
  - added json_encode/decode functions, basic strptime parsing
  - php5.1 functions fputcsv, property_exists, ... and constants
  - added dtools/php-commandline/PhpFunctionCall console script

v13
  - bcmath functions changed to use faster /usr/bin/dc, wrappers for GMP
    fixed and php_big_int.so usage possible
  - gettext_plural0 merged into old code and speed improved

v12
  - strripos() handling of positive offsets was fixed
  - strpbrk() fixed to not return string, if nothing found
  - php_strip_whitespace() and php_check_syntax() moved into ext/exotic
  + ext/bcmath using /usr/bin/bc
  + initial mhash (HMAC) implementation with MD5 and SHA1
  + incomplete ext/odbc
  + ext/exceptions for PHP4
  + extremely fast but incomplete plural form handling in gettext module
  - core script rewritten with more exhaustive comments

v11
  - shortened (whitespace- and comment-free) script was added
  - first gettext emulation version

v10
  (unreleased)

...
  (visit the BerliOS download page and diff it yourself)

v1
  - initial release (non-public)