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diff --git a/CODING_STANDARDS b/CODING_STANDARDS deleted file mode 100644 index b36c1fc3b2..0000000000 --- a/CODING_STANDARDS +++ /dev/null @@ -1,277 +0,0 @@ -PHP Coding Standards -==================== - - -This file lists several standards that any programmer, adding or changing -code in PHP, should follow. Since this file was added at a very late -stage of the development of PHP v3.0, the code base does not (yet) fully -follow it, but it's going in that general direction. Since we are now -well into the version 4 releases, many sections have been recoded to use -these rules. - - -Code Implementation -------------------- - -[0] Document your code in source files and the manual. [tm] - -[1] Functions that are given pointers to resources should not free them - -For instance, function int mail(char *to, char *from) should NOT free -to and/or from. -Exceptions: - - - The function's designated behavior is freeing that resource. E.g. efree() - - The function is given a boolean argument, that controls whether or not - the function may free its arguments (if true - the function must free its - arguments, if false - it must not) - - Low-level parser routines, that are tightly integrated with the token - cache and the bison code for minimum memory copying overhead. - -[2] Functions that are tightly integrated with other functions within the - same module, and rely on each other non-trivial behavior, should be - documented as such and declared 'static'. They should be avoided if - possible. - -[3] Use definitions and macros whenever possible, so that constants have - meaningful names and can be easily manipulated. The only exceptions - to this rule are 0 and 1, when used as false and true (respectively). - Any other use of a numeric constant to specify different behavior - or actions should be done through a #define. - -[4] When writing functions that deal with strings, be sure to remember - that PHP holds the length property of each string, and that it - shouldn't be calculated with strlen(). Write your functions in a such - a way so that they'll take advantage of the length property, both - for efficiency and in order for them to be binary-safe. - Functions that change strings and obtain their new lengths while - doing so, should return that new length, so it doesn't have to be - recalculated with strlen() (e.g. php_addslashes()) - -[5] NEVER USE strncat(). If you're absolutely sure you know what you're doing, - check its man page again, and only then, consider using it, and even then, - try avoiding it. - -[6] Use PHP_* macros in the PHP source, and ZEND_* macros in the Zend - part of the source. Although the PHP_* macro's are mostly aliased to the - ZEND_* macros it gives a better understanding on what kind of macro you're - calling. - -[7] When commenting out code using a #if statement, do NOT use 0 only. Instead - use "<cvs username here>_0". For example, #if FOO_0, where FOO is your - cvs user foo. This allows easier tracking of why code was commented out, - especially in bundled libraries. - -[8] Do not define functions that are not available. For instance, if a - library is missing a function, do not define the PHP version of the - function, and do not raise a run-time error about the function not - existing. End users should use function_exists() to test for the - existence of a function - -[9] Prefer emalloc(), efree(), estrdup(), etc. to their standard C library - counterparts. These functions implement an internal "safety-net" - mechanism that ensures the deallocation of any unfreed memory at the - end of a request. They also provide useful allocation and overflow - information while running in debug mode. - - In almost all cases, memory returned to the engine must be allocated - using emalloc(). - - The use of malloc() should be limited to cases where a third-party - library may need to control or free the memory, or when the memory in - question needs to survive between multiple requests. - -Naming Conventions ------------------- - -[1] Function names for user-level functions should be enclosed with in - the PHP_FUNCTION() macro. They should be in lowercase, with words - underscore delimited, with care taken to minimize the letter count. - Abbreviations should not be used when they greatly decrease the - readability of the function name itself. - - Good: - 'mcrypt_enc_self_test' - 'mysql_list_fields' - - Ok: - 'mcrypt_module_get_algo_supported_key_sizes' - (could be 'mcrypt_mod_get_algo_sup_key_sizes'?) - 'get_html_translation_table' - (could be 'html_get_trans_table'?) - - Bad: - 'hw_GetObjectByQueryCollObj' - 'pg_setclientencoding' - 'jf_n_s_i' - -[2] If they are part of a "parent set" of functions, that parent should - be included in the user function name, and should be clearly related - to the parent program or function family. This should be in the form - of parent_*. - - A family of 'foo' functions, for example: - Good: - 'foo_select_bar' - 'foo_insert_baz' - 'foo_delete_baz' - - Bad: - 'fooselect_bar' - 'fooinsertbaz' - 'delete_foo_baz' - -[3] Function names used by user functions should be prefixed - with "_php_", and followed by a word or an underscore-delimited list of - words, in lowercase letters, that describes the function. If applicable, - they should be declared 'static'. - -[4] Variable names must be meaningful. One letter variable names must be - avoided, except for places where the variable has no real meaning or - a trivial meaning (e.g. for (i=0; i<100; i++) ...). - -[5] Variable names should be in lowercase. Use underscores to separate - between words. - -[6] Method names follow the 'studlyCaps' (also referred to as 'bumpy case' - or 'camel caps') naming convention, with care taken to minimize the - letter count. The initial letter of the name is lowercase, and each - letter that starts a new 'word' is capitalized. - - Good: - 'connect()' - 'getData()' - 'buildSomeWidget()' - - Bad: - 'get_Data()' - 'buildsomewidget' - 'getI()' - -[7] Classes should be given descriptive names. Avoid using abbreviations where - possible. Each word in the class name should start with a capital letter, - without underscore delimiters (CampelCaps starting with a capital letter). - The class name should be prefixed with the name of the 'parent set' (e.g. - the name of the extension). - - Good: - 'Curl' - 'FooBar' - - Bad: - 'foobar' - 'foo_bar' - -Syntax and indentation ----------------------- - -[1] Never use C++ style comments (i.e. // comment). Always use C-style - comments instead. PHP is written in C, and is aimed at compiling - under any ANSI-C compliant compiler. Even though many compilers - accept C++-style comments in C code, you have to ensure that your - code would compile with other compilers as well. - The only exception to this rule is code that is Win32-specific, - because the Win32 port is MS-Visual C++ specific, and this compiler - is known to accept C++-style comments in C code. - -[2] Use K&R-style. Of course, we can't and don't want to - force anybody to use a style he or she is not used to, but, - at the very least, when you write code that goes into the core - of PHP or one of its standard modules, please maintain the K&R - style. This applies to just about everything, starting with - indentation and comment styles and up to function declaration - syntax. - - (see also http://www.catb.org/~esr/jargon/html/I/indent-style.html) - -[3] Be generous with whitespace and braces. Always prefer: - - if (foo) { - bar; - } - - to: - - if(foo)bar; - - Keep one empty line between the variable declaration section and - the statements in a block, as well as between logical statement - groups in a block. Maintain at least one empty line between - two functions, preferably two. - -[4] When indenting, use the tab character. A tab is expected to represent - four spaces. It is important to maintain consistency in indenture so - that definitions, comments, and control structures line up correctly. - -[5] Preprocessor statements (#if and such) MUST start at column one. To - indent preprocessor directives you should put the # at the beginning - of a line, followed by any number of whitespace. - -Testing -------- - -[1] Extensions should be well tested using *.phpt tests. Read about that - in README.TESTING. - -Documentation and Folding Hooks -------------------------------- - -In order to make sure that the online documentation stays in line with -the code, each user-level function should have its user-level function -prototype before it along with a brief one-line description of what the -function does. It would look like this: - -/* {{{ proto int abs(int number) - Returns the absolute value of the number */ -PHP_FUNCTION(abs) -{ - ... -} -/* }}} */ - -The {{{ symbols are the default folding symbols for the folding mode in -Emacs and vim (set fdm=marker). Folding is very useful when dealing with -large files because you can scroll through the file quickly and just unfold -the function you wish to work on. The }}} at the end of each function marks -the end of the fold, and should be on a separate line. - -The "proto" keyword there is just a helper for the doc/genfuncsummary script -which generates a full function summary. Having this keyword in front of the -function prototypes allows us to put folds elsewhere in the code without -messing up the function summary. - -Optional arguments are written like this: - -/* {{{ proto object imap_header(int stream_id, int msg_no [, int from_length [, int subject_length [, string default_host]]]) - Returns a header object with the defined parameters */ - -And yes, please keep the prototype on a single line, even if that line -is massive. - -New and Experimental Functions ------------------------------------ -To reduce the problems normally associated with the first public -implementation of a new set of functions, it has been suggested -that the first implementation include a file labeled 'EXPERIMENTAL' -in the function directory, and that the functions follow the -standard prefixing conventions during their initial implementation. - -The file labelled 'EXPERIMENTAL' should include the following -information: - Any authoring information (known bugs, future directions of the module). - Ongoing status notes which may not be appropriate for CVS comments. - -Aliases & Legacy Documentation ------------------------------------ -You may also have some deprecated aliases with close to duplicate -names, for example, somedb_select_result and somedb_selectresult. For -documentation purposes, these will only be documented by the most -current name, with the aliases listed in the documentation for -the parent function. For ease of reference, user-functions with -completely different names, that alias to the same function (such as -highlight_file and show_source), will be separately documented. The -proto should still be included, describing which function is aliased. - -Backwards compatible functions and names should be maintained as long -as the code can be reasonably be kept as part of the codebase. See -/phpdoc/README for more information on documentation. |