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diff --git a/README.EXT b/README.EXT deleted file mode 100644 index df075a63a4..0000000000 --- a/README.EXT +++ /dev/null @@ -1,1164 +0,0 @@ -.\" README.EXT - -*- Text -*- created at: Mon Aug 7 16:45:54 JST 1995 - -This document explains how to make extension libraries for Ruby. - -1. Basic knowledge - -In C, variables have types and data do not have types. In contrast, -Ruby variables do not have a static type, and data themselves have -types, so data will need to be converted between the languages. - -Data in Ruby are represented by the C type `VALUE'. Each VALUE data -has its data-type. - -To retrieve C data from a VALUE, you need to: - - (1) Identify the VALUE's data type - (2) Convert the VALUE into C data - -Converting to the wrong data type may cause serious problems. - - -1.1 Data-types - -The Ruby interpreter has the following data types: - - T_NIL nil - T_OBJECT ordinary object - T_CLASS class - T_MODULE module - T_FLOAT floating point number - T_STRING string - T_REGEXP regular expression - T_ARRAY array - T_FIXNUM Fixnum(31bit integer) - T_HASH associative array - T_STRUCT (Ruby) structure - T_BIGNUM multi precision integer - T_FILE IO - T_TRUE true - T_FALSE false - T_DATA data - T_SYMBOL symbol - -In addition, there are several other types used internally: - - T_ICLASS - T_MATCH - T_UNDEF - T_VARMAP - T_SCOPE - T_NODE - -Most of the types are represented by C structures. - -1.2 Check Data Type of the VALUE - -The macro TYPE() defined in ruby.h shows the data type of the VALUE. -TYPE() returns the constant number T_XXXX described above. To handle -data types, your code will look something like this: - - switch (TYPE(obj)) { - case T_FIXNUM: - /* process Fixnum */ - break; - case T_STRING: - /* process String */ - break; - case T_ARRAY: - /* process Array */ - break; - default: - /* raise exception */ - rb_raise(rb_eTypeError, "not valid value"); - break; - } - -There is the data-type check function - - void Check_Type(VALUE value, int type) - -which raises an exception if the VALUE does not have the type specified. - -There are also faster check macros for fixnums and nil. - - FIXNUM_P(obj) - NIL_P(obj) - -1.3 Convert VALUE into C data - -The data for type T_NIL, T_FALSE, T_TRUE are nil, true, false -respectively. They are singletons for the data type. - -The T_FIXNUM data is a 31bit length fixed integer (63bit length on -some machines), which can be converted to a C integer by using the -FIX2INT() macro. There is also NUM2INT() which converts any Ruby -numbers into C integers. The NUM2INT() macro includes a type check, so -an exception will be raised if the conversion failed. NUM2DBL() can -be used to retrieve the double float value in the same way. - -In version 1.7 or later it is recommended that you use the new macros -StringValue() and StringValuePtr() to get a char* from a VALUE. -StringValue(var) replaces var's value with the result of "var.to_str()". -StringValuePtr(var) does same replacement and returns char* -representation of var. These macros will skip the replacement if var is -a String. Notice that the macros take only the lvalue as their -argument, to change the value of var in place. - -In version 1.6 or earlier, STR2CSTR() was used to do the same thing -but now it is deprecated in version 1.7, because STR2CSTR() has a risk -of a dangling pointer problem in the to_str() impliclit conversion. - -Other data types have corresponding C structures, e.g. struct RArray -for T_ARRAY etc. The VALUE of the type which has the corresponding structure -can be cast to retrieve the pointer to the struct. The casting macro -will be of the form RXXXX for each data type; for instance, RARRAY(obj). -See "ruby.h". - -There are some accessing macros for structure members, for example -`RSTRING_LEN(s)' to to get the size of the Ruby String object. The -allocated region can be accessed by `RSTRING_PTR(str). For arrays, use -`RARRAY_LEN(ary) and `RARRAY_PTR(ary) respectively. - -Notice: Do not change the value of the structure directly, unless you -are responsible for the result. This ends up being the cause of interesting -bugs. - -1.4 Convert C data into VALUE - -To convert C data to Ruby values: - - * FIXNUM - - left shift 1 bit, and turn on LSB. - - * Other pointer values - - cast to VALUE. - -You can determine whether a VALUE is pointer or not by checking its LSB. - -Notice Ruby does not allow arbitrary pointer values to be a VALUE. They -should be pointers to the structures which Ruby knows about. The known -structures are defined in <ruby.h>. - -To convert C numbers to Ruby values, use these macros. - - INT2FIX() for integers within 31bits. - INT2NUM() for arbitrary sized integer. - -INT2NUM() converts an integer into a Bignum if it is out of the FIXNUM -range, but is a bit slower. - -1.5 Manipulating Ruby data - -As I already mentioned, it is not recommended to modify an object's internal -structure. To manipulate objects, use the functions supplied by the Ruby -interpreter. Some (not all) of the useful functions are listed below: - - String functions - - rb_str_new(const char *ptr, long len) - - Creates a new Ruby string. - - rb_str_new2(const char *ptr) - - Creates a new Ruby string from a C string. This is equivalent to - rb_str_new(ptr, strlen(ptr)). - - rb_tainted_str_new(const char *ptr, long len) - - Creates a new tainted Ruby string. Strings from external data - sources should be tainted. - - rb_tainted_str_new2(const char *ptr) - - Creates a new tainted Ruby string from a C string. - - rb_str_cat(VALUE str, const char *ptr, long len) - - Appends len bytes of data from ptr to the Ruby string. - - Array functions - - rb_ary_new() - - Creates an array with no elements. - - rb_ary_new2(long len) - - Creates an array with no elements, allocating internal buffer - for len elements. - - rb_ary_new3(long n, ...) - - Creates an n-element array from the arguments. - - rb_ary_new4(long n, VALUE *elts) - - Creates an n-element array from a C array. - - rb_ary_push(VALUE ary, VALUE val) - rb_ary_pop(VALUE ary) - rb_ary_shift(VALUE ary) - rb_ary_unshift(VALUE ary, VALUE val) - - Array operations. The first argument to each functions must be an - array. They may dump core if other types are given. - -2. Extending Ruby with C - -2.1 Addding new features to Ruby - -You can add new features (classes, methods, etc.) to the Ruby -interpreter. Ruby provides APIs for defining the following things: - - * Classes, Modules - * Methods, Singleton Methods - * Constants - -2.1.1 Class/module definition - -To define a class or module, use the functions below: - - VALUE rb_define_class(const char *name, VALUE super) - VALUE rb_define_module(const char *name) - -These functions return the newly created class or module. You may -want to save this reference into a variable to use later. - -To define nested classes or modules, use the functions below: - - VALUE rb_define_class_under(VALUE outer, const char *name, VALUE super) - VALUE rb_define_module_under(VALUE outer, const char *name) - -2.1.2 Method/singleton method definition - -To define methods or singleton methods, use these functions: - - void rb_define_method(VALUE klass, const char *name, - VALUE (*func)(), int argc) - - void rb_define_singleton_method(VALUE object, const char *name, - VALUE (*func)(), int argc) - -The `argc' represents the number of the arguments to the C function, -which must be less than 17. But I doubt you'll need that many. - -If `argc' is negative, it specifies the calling sequence, not number of -the arguments. - -If argc is -1, the function will be called as: - - VALUE func(int argc, VALUE *argv, VALUE obj) - -where argc is the actual number of arguments, argv is the C array of -the arguments, and obj is the receiver. - -If argc is -2, the arguments are passed in a Ruby array. The function -will be called like: - - VALUE func(VALUE obj, VALUE args) - -where obj is the receiver, and args is the Ruby array containing -actual arguments. - -There are two more functions to define methods. One is to define -private methods: - - void rb_define_private_method(VALUE klass, const char *name, - VALUE (*func)(), int argc) - -The other is to define module functions, which are private AND singleton -methods of the module. For example, sqrt is the module function -defined in Math module. It can be called in the following way: - - Math.sqrt(4) - -or - - include Math - sqrt(4) - -To define module functions, use: - - void rb_define_module_function(VALUE module, const char *name, - VALUE (*func)(), int argc) - -Oh, in addition, function-like methods, which are private methods defined -in the Kernel module, can be defined using: - - void rb_define_global_function(const char *name, VALUE (*func)(), int argc) - -To define an alias for the method, - - void rb_define_alias(VALUE module, const char* new, const char* old); - -To define and undefine the `allocate' class method, - - void rb_define_alloc_func(VALUE klass, VALUE (*func)(VALUE klass)); - void rb_undef_alloc_func(VALUE klass); - -func have to take the klass as the argument and return a newly -allocated instance. This instance should be empty as possible, -without any expensive (including external) resources. - -2.1.3 Constant definition - -We have 2 functions to define constants: - - void rb_define_const(VALUE klass, const char *name, VALUE val) - void rb_define_global_const(const char *name, VALUE val) - -The former is to define a constant under specified class/module. The -latter is to define a global constant. - -2.2 Use Ruby features from C - -There are several ways to invoke Ruby's features from C code. - -2.2.1 Evaluate Ruby Programs in a String - -The easiest way to use Ruby's functionality from a C program is to -evaluate the string as Ruby program. This function will do the job: - - VALUE rb_eval_string(const char *str) - -Evaluation is done under the current context, thus current local variables -of the innermost method (which is defined by Ruby) can be accessed. - -2.2.2 ID or Symbol - -You can invoke methods directly, without parsing the string. First I need -to explain about ID. ID is the integer number to represent Ruby's -identifiers such as variable names. The Ruby data type corresponding to ID -is Symbol. It can be accessed from Ruby in the form: - - :Identifier - -You can get the ID value from a string within C code by using - - rb_intern(const char *name) - -You can retrieve ID from Ruby object (Symbol or String) given as an -argument by using - - rb_to_id(VALUE symbol) - -You can convert C ID to Ruby Symbol by using - - VALUE ID2SYM(ID id) - -and to convert Ruby Symbol object to ID, use - - ID SYM2ID(VALUE symbol) - -2.2.3 Invoke Ruby method from C - -To invoke methods directly, you can use the function below - - VALUE rb_funcall(VALUE recv, ID mid, int argc, ...) - -This function invokes a method on the recv, with the method name -specified by the symbol mid. - -2.2.4 Accessing the variables and constants - -You can access class variables and instance variables using access -functions. Also, global variables can be shared between both environments. -There's no way to access Ruby's local variables. - -The functions to access/modify instance variables are below: - - VALUE rb_ivar_get(VALUE obj, ID id) - VALUE rb_ivar_set(VALUE obj, ID id, VALUE val) - -id must be the symbol, which can be retrieved by rb_intern(). - -To access the constants of the class/module: - - VALUE rb_const_get(VALUE obj, ID id) - -See 2.1.3 for defining new constant. - -3. Information sharing between Ruby and C - -3.1 Ruby constants that C can be accessed from C - -The following Ruby constants can be referred from C. - - Qtrue - Qfalse - -Boolean values. Qfalse is false in C also (i.e. 0). - - Qnil - -Ruby nil in C scope. - -3.2 Global variables shared between C and Ruby - -Information can be shared between the two environments using shared global -variables. To define them, you can use functions listed below: - - void rb_define_variable(const char *name, VALUE *var) - -This function defines the variable which is shared by both environments. -The value of the global variable pointed to by `var' can be accessed -through Ruby's global variable named `name'. - -You can define read-only (from Ruby, of course) variables using the -function below. - - void rb_define_readonly_variable(const char *name, VALUE *var) - -You can defined hooked variables. The accessor functions (getter and -setter) are called on access to the hooked variables. - - void rb_define_hooked_variable(constchar *name, VALUE *var, - VALUE (*getter)(), void (*setter)()) - -If you need to supply either setter or getter, just supply 0 for the -hook you don't need. If both hooks are 0, rb_define_hooked_variable() -works just like rb_define_variable(). - - void rb_define_virtual_variable(const char *name, - VALUE (*getter)(), void (*setter)()) - -This function defines a Ruby global variable without a corresponding C -variable. The value of the variable will be set/get only by hooks. - -The prototypes of the getter and setter functions are as follows: - - (*getter)(ID id, void *data, struct global_entry* entry); - (*setter)(VALUE val, ID id, void *data, struct global_entry* entry); - -3.3 Encapsulate C data into a Ruby object - -To wrap and objectify a C pointer as a Ruby object (so called -DATA), use Data_Wrap_Struct(). - - Data_Wrap_Struct(klass, mark, free, ptr) - -Data_Wrap_Struct() returns a created DATA object. The klass argument -is the class for the DATA object. The mark argument is the function -to mark Ruby objects pointed by this data. The free argument is the -function to free the pointer allocation. If this is -1, the pointer -will be just freed. The functions mark and free will be called from -garbage collector. - -You can allocate and wrap the structure in one step. - - Data_Make_Struct(klass, type, mark, free, sval) - -This macro returns an allocated Data object, wrapping the pointer to -the structure, which is also allocated. This macro works like: - - (sval = ALLOC(type), Data_Wrap_Struct(klass, mark, free, sval)) - -Arguments klass, mark, and free work like their counterparts in -Data_Wrap_Struct(). A pointer to the allocated structure will be -assigned to sval, which should be a pointer of the type specified. - -To retrieve the C pointer from the Data object, use the macro -Data_Get_Struct(). - - Data_Get_Struct(obj, type, sval) - -A pointer to the structure will be assigned to the variable sval. - -See the example below for details. - -4. Example - Creating dbm extension - -OK, here's the example of making an extension library. This is the -extension to access DBMs. The full source is included in the ext/ -directory in the Ruby's source tree. - -(1) make the directory - - % mkdir ext/dbm - -Make a directory for the extension library under ext directory. - -(2) design the library - -You need to design the library features, before making it. - -(3) write C code. - -You need to write C code for your extension library. If your library -has only one source file, choosing ``LIBRARY.c'' as a file name is -preferred. On the other hand, in case your library has multiple source -files, avoid choosing ``LIBRARY.c'' for a file name. It may conflict -with an intermediate file ``LIBRARY.o'' on some platforms. - -Ruby will execute the initializing function named ``Init_LIBRARY'' in -the library. For example, ``Init_dbm()'' will be executed when loading -the library. - -Here's the example of an initializing function. - --- -Init_dbm() -{ - /* define DBM class */ - cDBM = rb_define_class("DBM", rb_cObject); - /* DBM includes Enumerate module */ - rb_include_module(cDBM, rb_mEnumerable); - - /* DBM has class method open(): arguments are received as C array */ - rb_define_singleton_method(cDBM, "open", fdbm_s_open, -1); - - /* DBM instance method close(): no args */ - rb_define_method(cDBM, "close", fdbm_close, 0); - /* DBM instance method []: 1 argument */ - rb_define_method(cDBM, "[]", fdbm_fetch, 1); - : - - /* ID for a instance variable to store DBM data */ - id_dbm = rb_intern("dbm"); -} --- - -The dbm extension wraps the dbm struct in the C environment using -Data_Make_Struct. - --- -struct dbmdata { - int di_size; - DBM *di_dbm; -}; - - -obj = Data_Make_Struct(klass, struct dbmdata, 0, free_dbm, dbmp); --- - -This code wraps the dbmdata structure into a Ruby object. We avoid wrapping -DBM* directly, because we want to cache size information. - -To retrieve the dbmdata structure from a Ruby object, we define the -following macro: - --- -#define GetDBM(obj, dbmp) {\ - Data_Get_Struct(obj, struct dbmdata, dbmp);\ - if (dbmp->di_dbm == 0) closed_dbm();\ -} --- - -This sort of complicated macro does the retrieving and close checking for -the DBM. - -There are three kinds of way to receive method arguments. First, -methods with a fixed number of arguments receive arguments like this: - --- -static VALUE -fdbm_delete(obj, keystr) - VALUE obj, keystr; -{ - : -} --- - -The first argument of the C function is the self, the rest are the -arguments to the method. - -Second, methods with an arbitrary number of arguments receive -arguments like this: - --- -static VALUE -fdbm_s_open(argc, argv, klass) - int argc; - VALUE *argv; - VALUE klass; -{ - : - if (rb_scan_args(argc, argv, "11", &file, &vmode) == 1) { - mode = 0666; /* default value */ - } - : -} --- - -The first argument is the number of method arguments, the second -argument is the C array of the method arguments, and the third -argument is the receiver of the method. - -You can use the function rb_scan_args() to check and retrieve the -arguments. For example, "11" means that the method requires at least one -argument, and at most receives two arguments. - -Methods with an arbitrary number of arguments can receive arguments -by Ruby's array, like this: - --- -static VALUE -fdbm_indexes(obj, args) - VALUE obj, args; -{ - : -} --- - -The first argument is the receiver, the second one is the Ruby array -which contains the arguments to the method. - -** Notice - -GC should know about global variables which refer to Ruby's objects, but -are not exported to the Ruby world. You need to protect them by - - void rb_global_variable(VALUE *var) - -(4) prepare extconf.rb - -If the file named extconf.rb exists, it will be executed to generate -Makefile. - -extconf.rb is the file for checking compilation conditions etc. You -need to put - - require 'mkmf' - -at the top of the file. You can use the functions below to check -various conditions. - - have_library(lib, func): check whether library containing function exists. - have_func(func, header): check whether function exists - have_header(header): check whether header file exists - create_makefile(target): generate Makefile - -The value of the variables below will affect the Makefile. - - $CFLAGS: included in CFLAGS make variable (such as -O) - $CPPFLAGS: included in CPPFLAGS make variable (such as -I, -D) - $LDFLAGS: included in LDFLAGS make variable (such as -L) - $objs: list of object file names - -Normally, the object files list is automatically generated by searching -source files, but you must define them explicitly if any sources will -be generated while building. - -If a compilation condition is not fulfilled, you should not call -``create_makefile''. The Makefile will not be generated, compilation will -not be done. - -(5) prepare depend (optional) - -If the file named depend exists, Makefile will include that file to -check dependencies. You can make this file by invoking - - % gcc -MM *.c > depend - -It's harmless. Prepare it. - -(6) generate Makefile - -Try generating the Makefile by: - - ruby extconf.rb - -If the library should be installed under vendor_ruby directory -instead of site_ruby directory, use --vendor option as follows. - - ruby extconf.rb --vendor - -You don't need this step if you put the extension library under the ext -directory of the ruby source tree. In that case, compilation of the -interpreter will do this step for you. - -(7) make - -Type - - make - -to compile your extension. You don't need this step either if you have -put the extension library under the ext directory of the ruby source tree. - -(8) debug - -You may need to rb_debug the extension. Extensions can be linked -statically by adding the directory name in the ext/Setup file so that -you can inspect the extension with the debugger. - -(9) done, now you have the extension library - -You can do anything you want with your library. The author of Ruby -will not claim any restrictions on your code depending on the Ruby API. -Feel free to use, modify, distribute or sell your program. - -Appendix A. Ruby source files overview - -ruby language core - - class.c - error.c - eval.c - gc.c - object.c - parse.y - variable.c - -utility functions - - dln.c - regex.c - st.c - util.c - -ruby interpreter implementation - - dmyext.c - inits.c - main.c - ruby.c - version.c - -class library - - array.c - bignum.c - compar.c - dir.c - enum.c - file.c - hash.c - io.c - marshal.c - math.c - numeric.c - pack.c - prec.c - process.c - random.c - range.c - re.c - signal.c - sprintf.c - string.c - struct.c - time.c - -Appendix B. Ruby extension API reference - -** Types - - VALUE - -The type for the Ruby object. Actual structures are defined in ruby.h, -such as struct RString, etc. To refer the values in structures, use -casting macros like RSTRING(obj). - -** Variables and constants - - Qnil - -const: nil object - - Qtrue - -const: true object(default true value) - - Qfalse - -const: false object - -** C pointer wrapping - - Data_Wrap_Struct(VALUE klass, void (*mark)(), void (*free)(), void *sval) - -Wrap a C pointer into a Ruby object. If object has references to other -Ruby objects, they should be marked by using the mark function during -the GC process. Otherwise, mark should be 0. When this object is no -longer referred by anywhere, the pointer will be discarded by free -function. - - Data_Make_Struct(klass, type, mark, free, sval) - -This macro allocates memory using malloc(), assigns it to the variable -sval, and returns the DATA encapsulating the pointer to memory region. - - Data_Get_Struct(data, type, sval) - -This macro retrieves the pointer value from DATA, and assigns it to -the variable sval. - -** Checking data types - -TYPE(value) -FIXNUM_P(value) -NIL_P(value) -void Check_Type(VALUE value, int type) -void Check_SafeStr(VALUE value) - -** Data type conversion - -FIX2INT(value) -INT2FIX(i) -NUM2INT(value) -INT2NUM(i) -NUM2DBL(value) -rb_float_new(f) -StringValue(value) -StringValuePtr(value) -StringValueCStr(value) -rb_str_new2(s) - -** defining class/module - - VALUE rb_define_class(const char *name, VALUE super) - -Defines a new Ruby class as a subclass of super. - - VALUE rb_define_class_under(VALUE module, const char *name, VALUE super) - -Creates a new Ruby class as a subclass of super, under the module's -namespace. - - VALUE rb_define_module(const char *name) - -Defines a new Ruby module. - - VALUE rb_define_module_under(VALUE module, const char *name) - -Defines a new Ruby module under the module's namespace. - - void rb_include_module(VALUE klass, VALUE module) - -Includes module into class. If class already includes it, just -ignored. - - void rb_extend_object(VALUE object, VALUE module) - -Extend the object with the module's attributes. - -** Defining Global Variables - - void rb_define_variable(const char *name, VALUE *var) - -Defines a global variable which is shared between C and Ruby. If name -contains a character which is not allowed to be part of the symbol, -it can't be seen from Ruby programs. - - void rb_define_readonly_variable(const char *name, VALUE *var) - -Defines a read-only global variable. Works just like -rb_define_variable(), except the defined variable is read-only. - - void rb_define_virtual_variable(const char *name, - VALUE (*getter)(), VALUE (*setter)()) - -Defines a virtual variable, whose behavior is defined by a pair of C -functions. The getter function is called when the variable is -referenced. The setter function is called when the variable is set to a -value. The prototype for getter/setter functions are: - - VALUE getter(ID id) - void setter(VALUE val, ID id) - -The getter function must return the value for the access. - - void rb_define_hooked_variable(const char *name, VALUE *var, - VALUE (*getter)(), VALUE (*setter)()) - -Defines hooked variable. It's a virtual variable with a C variable. -The getter is called as - - VALUE getter(ID id, VALUE *var) - -returning a new value. The setter is called as - - void setter(VALUE val, ID id, VALUE *var) - -GC requires C global variables which hold Ruby values to be marked. - - void rb_global_variable(VALUE *var) - -Tells GC to protect these variables. - -** Constant Definition - - void rb_define_const(VALUE klass, const char *name, VALUE val) - -Defines a new constant under the class/module. - - void rb_define_global_const(const char *name, VALUE val) - -Defines a global constant. This is just the same as - - rb_define_const(cKernal, name, val) - -** Method Definition - - rb_define_method(VALUE klass, const char *name, VALUE (*func)(), int argc) - -Defines a method for the class. func is the function pointer. argc -is the number of arguments. if argc is -1, the function will receive -3 arguments: argc, argv, and self. if argc is -2, the function will -receive 2 arguments, self and args, where args is a Ruby array of -the method arguments. - - rb_define_private_method(VALUE klass, const char *name, VALUE (*func)(), int argc) - -Defines a private method for the class. Arguments are same as -rb_define_method(). - - rb_define_singleton_method(VALUE klass, const char *name, VALUE (*func)(), int argc) - -Defines a singleton method. Arguments are same as rb_define_method(). - - rb_scan_args(int argc, VALUE *argv, const char *fmt, ...) - -Retrieve argument from argc, argv. The fmt is the format string for -the arguments, such as "12" for 1 non-optional argument, 2 optional -arguments. If `*' appears at the end of fmt, it means the rest of -the arguments are assigned to the corresponding variable, packed in -an array. - -** Invoking Ruby method - - VALUE rb_funcall(VALUE recv, ID mid, int narg, ...) - -Invokes a method. To retrieve mid from a method name, use rb_intern(). - - VALUE rb_funcall2(VALUE recv, ID mid, int argc, VALUE *argv) - -Invokes a method, passing arguments by an array of values. - - VALUE rb_eval_string(const char *str) - -Compiles and executes the string as a Ruby program. - - ID rb_intern(const char *name) - -Returns ID corresponding to the name. - - char *rb_id2name(ID id) - -Returns the name corresponding ID. - - char *rb_class2name(VALUE klass) - -Returns the name of the class. - - int rb_respond_to(VALUE object, ID id) - -Returns true if the object responds to the message specified by id. - -** Instance Variables - - VALUE rb_iv_get(VALUE obj, const char *name) - -Retrieve the value of the instance variable. If the name is not -prefixed by `@', that variable shall be inaccessible from Ruby. - - VALUE rb_iv_set(VALUE obj, const char *name, VALUE val) - -Sets the value of the instance variable. - -** Control Structure - - VALUE rb_iterate(VALUE (*func1)(), void *arg1, VALUE (*func2)(), void *arg2) - -Calls the function func1, supplying func2 as the block. func1 will be -called with the argument arg1. func2 receives the value from yield as -the first argument, arg2 as the second argument. - - VALUE rb_yield(VALUE val) - -Evaluates the block with value val. - - VALUE rb_rescue(VALUE (*func1)(), void *arg1, VALUE (*func2)(), void *arg2) - -Calls the function func1, with arg1 as the argument. If an exception -occurs during func1, it calls func2 with arg2 as the argument. The -return value of rb_rescue() is the return value from func1 if no -exception occurs, from func2 otherwise. - - VALUE rb_ensure(VALUE (*func1)(), void *arg1, void (*func2)(), void *arg2) - -Calls the function func1 with arg1 as the argument, then calls func2 -with arg2 if execution terminated. The return value from -rb_ensure() is that of func1. - -** Exceptions and Errors - - void rb_warn(const char *fmt, ...) - -Prints a warning message according to a printf-like format. - - void rb_warning(const char *fmt, ...) - -Prints a warning message according to a printf-like format, if -$VERBOSE is true. - -void rb_raise(rb_eRuntimeError, const char *fmt, ...) - -Raises RuntimeError. The fmt is a format string just like printf(). - - void rb_raise(VALUE exception, const char *fmt, ...) - -Raises a class exception. The fmt is a format string just like printf(). - - void rb_fatal(const char *fmt, ...) - -Raises a fatal error, terminates the interpreter. No exception handling -will be done for fatal errors, but ensure blocks will be executed. - - void rb_bug(const char *fmt, ...) - -Terminates the interpreter immediately. This function should be -called under the situation caused by the bug in the interpreter. No -exception handling nor ensure execution will be done. - -** Initialize and Start the Interpreter - -The embedding API functions are below (not needed for extension libraries): - - void ruby_init() - -Initializes the interpreter. - - void ruby_options(int argc, char **argv) - -Process command line arguments for the interpreter. - - void ruby_run() - -Starts execution of the interpreter. - - void ruby_script(char *name) - -Specifies the name of the script ($0). - -** Hooks for the Interpreter Events - - void rb_add_event_hook(rb_event_hook_func_t func, rb_event_t events) - -Adds a hook function for the specified interpreter events. -events should be Or'ed value of: - - RUBY_EVENT_LINE - RUBY_EVENT_CLASS - RUBY_EVENT_END - RUBY_EVENT_CALL - RUBY_EVENT_RETURN - RUBY_EVENT_C_CALL - RUBY_EVENT_C_RETURN - RUBY_EVENT_RAISE - RUBY_EVENT_ALL - -The definition of rb_event_hook_func_t is below: - - typedef void (*rb_event_hook_func_t)(rb_event_t event, NODE *node, - VALUE self, ID id, VALUE klass) - - int rb_remove_event_hook(rb_event_hook_func_t func) - -Removes the specified hook function. - -Appendix C. Functions Available in extconf.rb - -These functions are available in extconf.rb: - - have_macro(macro, headers) - -Checks whether macro is defined with header. Returns true if the macro -is defined. - - have_library(lib, func) - -Checks whether the library exists, containing the specified function. -Returns true if the library exists. - - find_library(lib, func, path...) - -Checks whether a library which contains the specified function exists in -path. Returns true if the library exists. - - have_func(func, header) - -Checks whether func exists with header. Returns true if the function -exists. To check functions in an additional library, you need to -check that library first using have_library(). - - have_var(var, header) - -Checks whether var exists with header. Returns true if the variable -exists. To check variables in an additional library, you need to -check that library first using have_library(). - - have_header(header) - -Checks whether header exists. Returns true if the header file exists. - - find_header(header, path...) - -Checks whether header exists in path. Returns true if the header file -exists. - - have_struct_member(type, member, header) - -Checks whether type has member with header. Returns true if the type -is defined and has the member. - - have_type(type, header, opt) - -Checks whether type is defined with header. Returns true if the type -is defined. - - check_sizeof(type, header) - -Checks the size of type in char with header. Returns the size if the -type is defined, otherwise nil. - - create_makefile(target) - -Generates the Makefile for the extension library. If you don't invoke -this method, the compilation will not be done. - - find_executable(bin, path) - -Finds command in path, which is File::PATH_SEPARATOR-separated list of -directories. If path is nil or omitted, environment varialbe PATH -will be used. Returns the path name of the command if it is found, -otherwise nil. - - with_config(withval[, default=nil]) - -Parses the command line options and returns the value specified by ---with-<withval>. - - enable_config(config, *defaults) - disable_config(config, *defaults) - -Parses the command line options for boolean. Returns true if ---enable-<config> is given, or false if --disable-<config> is given. -Otherwise, yields defaults to the given block and returns the result -if it is called with a block, or returns defaults. - - dir_config(target[, default_dir]) - dir_config(target[, default_include, default_lib]) - -Parses the command line options and adds the directories specified by ---with-<target>-dir, --with-<target>-include, and/or --with-<target>-lib -to $CFLAGS and/or $LDFLAGS. --with-<target>-dir=/path is equivalent to ---with-<target>-include=/path/include --with-<target>-lib=/path/lib. -Returns an array of the added directories ([include_dir, lib_dir]). - - pkg_config(pkg) - -Obtains the information for pkg by pkg-config command. The actual -command name can be overriden by --with-pkg-config command line -option. - -/* - * Local variables: - * fill-column: 70 - * end: - */ |