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    1: (NOTE: you may also want to take a look at the pear package
    2: 	     PECL_Gen, a PHP-only alternative for this script that
    3: 			 supports way more extension writing tasks and is 
    4: 			 supposed to replace ext_skel completely in the long run ...)
    5: 
    6: WHAT IT IS
    7: 
    8:   It's a tool for automatically creating the basic framework for a PHP module
    9:   and writing C code handling arguments passed to your functions from a simple
   10:   configuration file. See an example at the end of this file.
   11: 
   12: HOW TO USE IT
   13: 
   14:   Very simple. First, change to the ext/ directory of the PHP 4 sources. If
   15:   you just need the basic framework and will be writing all the code in your
   16:   functions yourself, you can now do
   17: 
   18:    ./ext_skel --extname=module_name
   19: 
   20:   and everything you need is placed in directory module_name. 
   21: 
   22:   [ Note that GNU awk is likely required for this script to work.  Debian 
   23:     systems seem to default to using mawk, so you may need to change the 
   24:     #! line in skeleton/create_stubs and the cat $proto | awk line in
   25:     ext_skel to use gawk explicitly. ]
   26: 
   27:   If you don't need to test the existence of any external header files, 
   28:   libraries or functions in them, the module is already almost ready to be 
   29:   compiled in PHP.  Just remove 3 comments in your_module_name/config.m4, 
   30:   change back up to PHP sources top directory, and do
   31: 
   32:     ./buildconf; ./configure --enable-module_name; make
   33: 
   34:   But if you already have planned the overall scheme of your module, what
   35:   functions it will contain, their return types and the arguments they take
   36:   (a very good idea) and don't want to bother yourself with creating function
   37:   definitions and handling arguments passed yourself, it's time to create a
   38:   function definitions file, which you will give as an argument to ext_skel
   39:   with option
   40: 
   41:     --proto=filename.
   42: 
   43: FORMAT OF FUNCTION DEFINITIONS FILE
   44: 
   45:   All the definitions must be on one line. In it's simplest form, it's just
   46:   the function name, e.g.
   47: 
   48:     my_function
   49: 
   50:   but then you'll be left with an almost empty function body without any
   51:   argument handling.
   52: 
   53:   Arguments are given in parenthesis after the function name, and are of
   54:   the form 'argument_type argument_name'. Arguments are separated from each
   55:   other with a comma and optional space. Argument_type can be one of int,
   56:   bool, double, float, string, array, object or mixed.
   57: 
   58:   An optional argument is separated from the previous by an optional space,
   59:   then '[' and of course comma and optional space, like all the other
   60:   arguments. You should close a row of optional arguments with same amount of
   61:   ']'s as there where '['s. Currently, it does not harm if you forget to do it
   62:   or there is a wrong amount of ']'s, but this may change in the future.
   63: 
   64: 	An additional short description may be added after the parameters. 
   65:   If present it will be filled into the 'proto' header comments in the stubs
   66:   code and the <refpurpose> tag in the XML documentation.
   67: 
   68:   An example:
   69: 
   70:     my_function(int arg1, int arg2 [, int arg3 [, int arg4]]) this is my 1st
   71: 
   72:   Arguments arg3 and arg4 are optional.
   73: 
   74:   If possible, the function definition should also contain it's return type
   75:   in front of the definition. It's not actually used for any C code generating
   76:   purposes but PHP in-source documentation instead, and as such, very useful.
   77:   It can be any of int, double, string, bool, array, object, resource, mixed
   78:   or void.
   79: 
   80:   The file must contain nothing else but function definitions, no comments or
   81:   empty lines.
   82: 
   83: OTHER OPTIONS
   84: 
   85:     --no-help
   86: 
   87:   By default, ext_skel creates both comments in the source code and a test
   88:   function to help first time module writers to get started and testing
   89:   configuring and compiling their module. This option turns off all such things
   90:   which may just annoy experienced PHP module coders. Especially useful with
   91: 
   92:     --stubs=file
   93: 
   94:   which will leave out also all module specific stuff and write just function
   95:   stubs with function value declarations and passed argument handling, and
   96:   function entries and definitions at the end of the file, for copying and
   97:   pasting into an already existing module.
   98: 
   99:     --xml[=file]
  100: 
  101:   Creates the basics for phpdoc .xml file.
  102: 
  103:     --full-xml
  104: 
  105:   Not implemented yet. When or if there will ever be created a framework for
  106:   self-contained extensions to use phpdoc system for their documentation, this
  107:   option enables it on the created xml file.
  108: 
  109: CURRENT LIMITATIONS, BUGS AND OTHER ODDITIES
  110: 
  111:   Only arguments of types int, bool, double, float, string and array are
  112:   handled. For other types you must write the code yourself. And for type
  113:   mixed, it wouldn't even be possible to write anything, because only you
  114:   know what to expect.
  115:   
  116:   It can't handle correctly, and probably never will, variable list of
  117:   of arguments. (void foo(int bar [, ...])
  118: 
  119:   Don't trust the generated code too much. It tries to be useful in most of
  120:   the situations you might encounter, but automatic code generation will never
  121:   beat a programmer who knows the real situation at hand. ext_skel is generally
  122:   best suited for quickly generating a wrapper for c-library functions you
  123:   might want to have available in PHP too.
  124: 
  125:   This program doesn't have a --help option. It has --no-help instead.
  126: 
  127: EXAMPLE
  128: 
  129:   The following _one_ line
  130: 
  131:   bool my_drawtext(resource image, string text, resource font, int x, int y [, int color])
  132: 
  133:   will create this function definition for you (note that there are a few
  134:   question marks to be replaced by you, and you must of course add your own
  135:   value definitions too):
  136: 
  137: /* {{{ proto bool my_drawtext(resource image, string text, resource font, int x, int y [, int color])
  138:     */
  139: PHP_FUNCTION(my_drawtext)
  140: {
  141:     char *text = NULL;
  142:     int argc = ZEND_NUM_ARGS();
  143:     int image_id = -1;
  144:     int text_len;
  145:     int font_id = -1;
  146:     long x;
  147:     long y;
  148:     long color;
  149:     zval *image = NULL;
  150:     zval *font = NULL;
  151: 
  152:     if (zend_parse_parameters(argc TSRMLS_CC, "rsrll|l", &image, &text, &text_len, &font, &x, &y, &color) == FAILURE)
  153:         return;
  154: 
  155:     if (image) {
  156:         ZEND_FETCH_RESOURCE(???, ???, image, image_id, "???", ???_rsrc_id);
  157:     }
  158:     if (font) {
  159:         ZEND_FETCH_RESOURCE(???, ???, font, font_id, "???", ???_rsrc_id);
  160:     }
  161: 
  162:     php_error(E_WARNING, "my_drawtext: not yet implemented");
  163: }
  164: /* }}} */
  165: