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-rw-r--r--ext/fiddle/pointer.c691
1 files changed, 691 insertions, 0 deletions
diff --git a/ext/fiddle/pointer.c b/ext/fiddle/pointer.c
new file mode 100644
index 0000000000..7cf8212cda
--- /dev/null
+++ b/ext/fiddle/pointer.c
@@ -0,0 +1,691 @@
+/* -*- C -*-
+ * $Id$
+ */
+
+#include <ruby/ruby.h>
+#include <ruby/io.h>
+#include <ctype.h>
+#include <fiddle.h>
+
+VALUE rb_cPointer;
+
+typedef void (*freefunc_t)(void*);
+
+struct ptr_data {
+ void *ptr;
+ long size;
+ freefunc_t free;
+ VALUE wrap[2];
+};
+
+#define RPTR_DATA(obj) ((struct ptr_data *)(DATA_PTR(obj)))
+
+static inline freefunc_t
+get_freefunc(VALUE func, volatile VALUE *wrap)
+{
+ VALUE addrnum;
+ if (NIL_P(func)) {
+ *wrap = 0;
+ return NULL;
+ }
+ addrnum = rb_Integer(func);
+ *wrap = (addrnum != func) ? func : 0;
+ return (freefunc_t)(VALUE)NUM2PTR(addrnum);
+}
+
+static ID id_to_ptr;
+
+static void
+fiddle_ptr_mark(void *ptr)
+{
+ struct ptr_data *data = ptr;
+ if (data->wrap[0]) {
+ rb_gc_mark(data->wrap[0]);
+ }
+ if (data->wrap[1]) {
+ rb_gc_mark(data->wrap[1]);
+ }
+}
+
+static void
+fiddle_ptr_free(void *ptr)
+{
+ struct ptr_data *data = ptr;
+ if (data->ptr) {
+ if (data->free) {
+ (*(data->free))(data->ptr);
+ }
+ }
+}
+
+static size_t
+fiddle_ptr_memsize(const void *ptr)
+{
+ const struct ptr_data *data = ptr;
+ return data ? sizeof(*data) + data->size : 0;
+}
+
+static const rb_data_type_t fiddle_ptr_data_type = {
+ "fiddle/pointer",
+ {fiddle_ptr_mark, fiddle_ptr_free, fiddle_ptr_memsize,},
+};
+
+static VALUE
+rb_fiddle_ptr_new2(VALUE klass, void *ptr, long size, freefunc_t func)
+{
+ struct ptr_data *data;
+ VALUE val;
+
+ rb_secure(4);
+ val = TypedData_Make_Struct(klass, struct ptr_data, &fiddle_ptr_data_type, data);
+ data->ptr = ptr;
+ data->free = func;
+ data->size = size;
+ OBJ_TAINT(val);
+
+ return val;
+}
+
+static VALUE
+rb_fiddle_ptr_new(void *ptr, long size, freefunc_t func)
+{
+ return rb_fiddle_ptr_new2(rb_cPointer, ptr, size, func);
+}
+
+static VALUE
+rb_fiddle_ptr_malloc(long size, freefunc_t func)
+{
+ void *ptr;
+
+ rb_secure(4);
+ ptr = ruby_xmalloc((size_t)size);
+ memset(ptr,0,(size_t)size);
+ return rb_fiddle_ptr_new(ptr, size, func);
+}
+
+static void *
+rb_fiddle_ptr2cptr(VALUE val)
+{
+ struct ptr_data *data;
+ void *ptr;
+
+ if (rb_obj_is_kind_of(val, rb_cPointer)) {
+ TypedData_Get_Struct(val, struct ptr_data, &fiddle_ptr_data_type, data);
+ ptr = data->ptr;
+ }
+ else if (val == Qnil) {
+ ptr = NULL;
+ }
+ else{
+ rb_raise(rb_eTypeError, "DL::PtrData was expected");
+ }
+
+ return ptr;
+}
+
+static VALUE
+rb_fiddle_ptr_s_allocate(VALUE klass)
+{
+ VALUE obj;
+ struct ptr_data *data;
+
+ rb_secure(4);
+ obj = TypedData_Make_Struct(klass, struct ptr_data, &fiddle_ptr_data_type, data);
+ data->ptr = 0;
+ data->size = 0;
+ data->free = 0;
+
+ return obj;
+}
+
+/*
+ * call-seq:
+ * Fiddle::Pointer.new(address) => fiddle_cptr
+ * Fiddle::Pointer.new(address, size) => fiddle_cptr
+ * Fiddle::Pointer.new(address, size, freefunc) => fiddle_cptr
+ *
+ * Create a new pointer to +address+ with an optional +size+ and +freefunc+.
+ * +freefunc+ will be called when the instance is garbage collected.
+ */
+static VALUE
+rb_fiddle_ptr_initialize(int argc, VALUE argv[], VALUE self)
+{
+ VALUE ptr, sym, size, wrap = 0, funcwrap = 0;
+ struct ptr_data *data;
+ void *p = NULL;
+ freefunc_t f = NULL;
+ long s = 0;
+
+ if (rb_scan_args(argc, argv, "12", &ptr, &size, &sym) >= 1) {
+ VALUE addrnum = rb_Integer(ptr);
+ if (addrnum != ptr) wrap = ptr;
+ p = NUM2PTR(addrnum);
+ }
+ if (argc >= 2) {
+ s = NUM2LONG(size);
+ }
+ if (argc >= 3) {
+ f = get_freefunc(sym, &funcwrap);
+ }
+
+ if (p) {
+ TypedData_Get_Struct(self, struct ptr_data, &fiddle_ptr_data_type, data);
+ if (data->ptr && data->free) {
+ /* Free previous memory. Use of inappropriate initialize may cause SEGV. */
+ (*(data->free))(data->ptr);
+ }
+ data->wrap[0] = wrap;
+ data->wrap[1] = funcwrap;
+ data->ptr = p;
+ data->size = s;
+ data->free = f;
+ }
+
+ return Qnil;
+}
+
+/*
+ * call-seq:
+ *
+ * Fiddle::Pointer.malloc(size, freefunc = nil) => fiddle pointer instance
+ *
+ * Allocate +size+ bytes of memory and associate it with an optional
+ * +freefunc+ that will be called when the pointer is garbage collected.
+ * +freefunc+ must be an address pointing to a function or an instance of
+ * Fiddle::Function
+ */
+static VALUE
+rb_fiddle_ptr_s_malloc(int argc, VALUE argv[], VALUE klass)
+{
+ VALUE size, sym, obj, wrap = 0;
+ long s;
+ freefunc_t f;
+
+ switch (rb_scan_args(argc, argv, "11", &size, &sym)) {
+ case 1:
+ s = NUM2LONG(size);
+ f = NULL;
+ break;
+ case 2:
+ s = NUM2LONG(size);
+ f = get_freefunc(sym, &wrap);
+ break;
+ default:
+ rb_bug("rb_fiddle_ptr_s_malloc");
+ }
+
+ obj = rb_fiddle_ptr_malloc(s,f);
+ if (wrap) RPTR_DATA(obj)->wrap[1] = wrap;
+
+ return obj;
+}
+
+/*
+ * call-seq: to_i
+ *
+ * Returns the integer memory location of this DL::CPtr.
+ */
+static VALUE
+rb_fiddle_ptr_to_i(VALUE self)
+{
+ struct ptr_data *data;
+
+ TypedData_Get_Struct(self, struct ptr_data, &fiddle_ptr_data_type, data);
+ return PTR2NUM(data->ptr);
+}
+
+/*
+ * call-seq: to_value
+ *
+ * Cast this CPtr to a ruby object.
+ */
+static VALUE
+rb_fiddle_ptr_to_value(VALUE self)
+{
+ struct ptr_data *data;
+ TypedData_Get_Struct(self, struct ptr_data, &fiddle_ptr_data_type, data);
+ return (VALUE)(data->ptr);
+}
+
+/*
+ * call-seq: ptr
+ *
+ * Returns a DL::CPtr that is a dereferenced pointer for this DL::CPtr.
+ * Analogous to the star operator in C.
+ */
+static VALUE
+rb_fiddle_ptr_ptr(VALUE self)
+{
+ struct ptr_data *data;
+
+ TypedData_Get_Struct(self, struct ptr_data, &fiddle_ptr_data_type, data);
+ return rb_fiddle_ptr_new(*((void**)(data->ptr)),0,0);
+}
+
+/*
+ * call-seq: ref
+ *
+ * Returns a DL::CPtr that is a reference pointer for this DL::CPtr.
+ * Analogous to the ampersand operator in C.
+ */
+static VALUE
+rb_fiddle_ptr_ref(VALUE self)
+{
+ struct ptr_data *data;
+
+ TypedData_Get_Struct(self, struct ptr_data, &fiddle_ptr_data_type, data);
+ return rb_fiddle_ptr_new(&(data->ptr),0,0);
+}
+
+/*
+ * call-seq: null?
+ *
+ * Returns true if this is a null pointer.
+ */
+static VALUE
+rb_fiddle_ptr_null_p(VALUE self)
+{
+ struct ptr_data *data;
+
+ TypedData_Get_Struct(self, struct ptr_data, &fiddle_ptr_data_type, data);
+ return data->ptr ? Qfalse : Qtrue;
+}
+
+/*
+ * call-seq: free=(function)
+ *
+ * Set the free function for this pointer to the DL::CFunc in +function+.
+ */
+static VALUE
+rb_fiddle_ptr_free_set(VALUE self, VALUE val)
+{
+ struct ptr_data *data;
+
+ TypedData_Get_Struct(self, struct ptr_data, &fiddle_ptr_data_type, data);
+ data->free = get_freefunc(val, &data->wrap[1]);
+
+ return Qnil;
+}
+
+/*
+ * call-seq: free
+ *
+ * Get the free function for this pointer. Returns Fiddle::Function.
+ */
+static VALUE
+rb_fiddle_ptr_free_get(VALUE self)
+{
+ struct ptr_data *pdata;
+ VALUE address;
+ VALUE arg_types;
+ VALUE ret_type;
+
+ TypedData_Get_Struct(self, struct ptr_data, &fiddle_ptr_data_type, pdata);
+
+ if (!pdata->free)
+ return Qnil;
+
+ address = PTR2NUM(pdata->free);
+ ret_type = INT2NUM(TYPE_VOID);
+ arg_types = rb_ary_new();
+ rb_ary_push(arg_types, INT2NUM(TYPE_VOIDP));
+
+ return rb_fiddle_new_function(address, arg_types, ret_type);
+}
+
+/*
+ * call-seq:
+ *
+ * ptr.to_s => string
+ * ptr.to_s(len) => string
+ *
+ * Returns the pointer contents as a string. When called with no arguments,
+ * this method will return the contents until the first NULL byte. When
+ * called with +len+, a string of +len+ bytes will be returned.
+ */
+static VALUE
+rb_fiddle_ptr_to_s(int argc, VALUE argv[], VALUE self)
+{
+ struct ptr_data *data;
+ VALUE arg1, val;
+ int len;
+
+ TypedData_Get_Struct(self, struct ptr_data, &fiddle_ptr_data_type, data);
+ switch (rb_scan_args(argc, argv, "01", &arg1)) {
+ case 0:
+ val = rb_tainted_str_new2((char*)(data->ptr));
+ break;
+ case 1:
+ len = NUM2INT(arg1);
+ val = rb_tainted_str_new((char*)(data->ptr), len);
+ break;
+ default:
+ rb_bug("rb_fiddle_ptr_to_s");
+ }
+
+ return val;
+}
+
+/*
+ * call-seq:
+ *
+ * ptr.to_str => string
+ * ptr.to_str(len) => string
+ *
+ * Returns the pointer contents as a string. When called with no arguments,
+ * this method will return the contents with the length of this pointer's
+ * +size+. When called with +len+, a string of +len+ bytes will be returned.
+ */
+static VALUE
+rb_fiddle_ptr_to_str(int argc, VALUE argv[], VALUE self)
+{
+ struct ptr_data *data;
+ VALUE arg1, val;
+ int len;
+
+ TypedData_Get_Struct(self, struct ptr_data, &fiddle_ptr_data_type, data);
+ switch (rb_scan_args(argc, argv, "01", &arg1)) {
+ case 0:
+ val = rb_tainted_str_new((char*)(data->ptr),data->size);
+ break;
+ case 1:
+ len = NUM2INT(arg1);
+ val = rb_tainted_str_new((char*)(data->ptr), len);
+ break;
+ default:
+ rb_bug("rb_fiddle_ptr_to_str");
+ }
+
+ return val;
+}
+
+/*
+ * call-seq: inspect
+ *
+ * Returns a string formatted with an easily readable representation of the
+ * internal state of the DL::CPtr
+ */
+static VALUE
+rb_fiddle_ptr_inspect(VALUE self)
+{
+ struct ptr_data *data;
+ char str[1024];
+
+ TypedData_Get_Struct(self, struct ptr_data, &fiddle_ptr_data_type, data);
+ snprintf(str, 1023, "#<%s:%p ptr=%p size=%ld free=%p>",
+ rb_class2name(CLASS_OF(self)), data, data->ptr, data->size, data->free);
+ return rb_str_new2(str);
+}
+
+/*
+ * call-seq:
+ * ptr == other => true or false
+ * ptr.eql?(other) => true or false
+ *
+ * Returns true if +other+ wraps the same pointer, otherwise returns
+ * false.
+ */
+static VALUE
+rb_fiddle_ptr_eql(VALUE self, VALUE other)
+{
+ void *ptr1, *ptr2;
+
+ if(!rb_obj_is_kind_of(other, rb_cPointer)) return Qfalse;
+
+ ptr1 = rb_fiddle_ptr2cptr(self);
+ ptr2 = rb_fiddle_ptr2cptr(other);
+
+ return ptr1 == ptr2 ? Qtrue : Qfalse;
+}
+
+/*
+ * call-seq:
+ * ptr <=> other => -1, 0, 1, or nil
+ *
+ * Returns -1 if less than, 0 if equal to, 1 if greater than +other+. Returns
+ * nil if +ptr+ cannot be compared to +other+.
+ */
+static VALUE
+rb_fiddle_ptr_cmp(VALUE self, VALUE other)
+{
+ void *ptr1, *ptr2;
+ SIGNED_VALUE diff;
+
+ if(!rb_obj_is_kind_of(other, rb_cPointer)) return Qnil;
+
+ ptr1 = rb_fiddle_ptr2cptr(self);
+ ptr2 = rb_fiddle_ptr2cptr(other);
+ diff = (SIGNED_VALUE)ptr1 - (SIGNED_VALUE)ptr2;
+ if (!diff) return INT2FIX(0);
+ return diff > 0 ? INT2NUM(1) : INT2NUM(-1);
+}
+
+/*
+ * call-seq:
+ * ptr + n => new cptr
+ *
+ * Returns a new DL::CPtr that has been advanced +n+ bytes.
+ */
+static VALUE
+rb_fiddle_ptr_plus(VALUE self, VALUE other)
+{
+ void *ptr;
+ long num, size;
+
+ ptr = rb_fiddle_ptr2cptr(self);
+ size = RPTR_DATA(self)->size;
+ num = NUM2LONG(other);
+ return rb_fiddle_ptr_new((char *)ptr + num, size - num, 0);
+}
+
+/*
+ * call-seq:
+ * ptr - n => new cptr
+ *
+ * Returns a new DL::CPtr that has been moved back +n+ bytes.
+ */
+static VALUE
+rb_fiddle_ptr_minus(VALUE self, VALUE other)
+{
+ void *ptr;
+ long num, size;
+
+ ptr = rb_fiddle_ptr2cptr(self);
+ size = RPTR_DATA(self)->size;
+ num = NUM2LONG(other);
+ return rb_fiddle_ptr_new((char *)ptr - num, size + num, 0);
+}
+
+/*
+ * call-seq:
+ * ptr[index] -> an_integer
+ * ptr[start, length] -> a_string
+ *
+ * Returns integer stored at _index_. If _start_ and _length_ are given,
+ * a string containing the bytes from _start_ of length _length_ will be
+ * returned.
+ */
+static VALUE
+rb_fiddle_ptr_aref(int argc, VALUE argv[], VALUE self)
+{
+ VALUE arg0, arg1;
+ VALUE retval = Qnil;
+ size_t offset, len;
+ struct ptr_data *data;
+
+ TypedData_Get_Struct(self, struct ptr_data, &fiddle_ptr_data_type, data);
+ if (!data->ptr) rb_raise(rb_eFiddleError, "NULL pointer dereference");
+ switch( rb_scan_args(argc, argv, "11", &arg0, &arg1) ){
+ case 1:
+ offset = NUM2ULONG(arg0);
+ retval = INT2NUM(*((char *)data->ptr + offset));
+ break;
+ case 2:
+ offset = NUM2ULONG(arg0);
+ len = NUM2ULONG(arg1);
+ retval = rb_tainted_str_new((char *)data->ptr + offset, len);
+ break;
+ default:
+ rb_bug("rb_fiddle_ptr_aref()");
+ }
+ return retval;
+}
+
+/*
+ * call-seq:
+ * ptr[index] = int -> int
+ * ptr[start, length] = string or cptr or addr -> string or dl_cptr or addr
+ *
+ * Set the value at +index+ to +int+. Or, set the memory at +start+ until
+ * +length+ with the contents of +string+, the memory from +dl_cptr+, or the
+ * memory pointed at by the memory address +addr+.
+ */
+static VALUE
+rb_fiddle_ptr_aset(int argc, VALUE argv[], VALUE self)
+{
+ VALUE arg0, arg1, arg2;
+ VALUE retval = Qnil;
+ size_t offset, len;
+ void *mem;
+ struct ptr_data *data;
+
+ TypedData_Get_Struct(self, struct ptr_data, &fiddle_ptr_data_type, data);
+ if (!data->ptr) rb_raise(rb_eFiddleError, "NULL pointer dereference");
+ switch( rb_scan_args(argc, argv, "21", &arg0, &arg1, &arg2) ){
+ case 2:
+ offset = NUM2ULONG(arg0);
+ ((char*)data->ptr)[offset] = NUM2UINT(arg1);
+ retval = arg1;
+ break;
+ case 3:
+ offset = NUM2ULONG(arg0);
+ len = NUM2ULONG(arg1);
+ if (RB_TYPE_P(arg2, T_STRING)) {
+ mem = StringValuePtr(arg2);
+ }
+ else if( rb_obj_is_kind_of(arg2, rb_cPointer) ){
+ mem = rb_fiddle_ptr2cptr(arg2);
+ }
+ else{
+ mem = NUM2PTR(arg2);
+ }
+ memcpy((char *)data->ptr + offset, mem, len);
+ retval = arg2;
+ break;
+ default:
+ rb_bug("rb_fiddle_ptr_aset()");
+ }
+ return retval;
+}
+
+/*
+ * call-seq: size=(size)
+ *
+ * Set the size of this pointer to +size+
+ */
+static VALUE
+rb_fiddle_ptr_size_set(VALUE self, VALUE size)
+{
+ RPTR_DATA(self)->size = NUM2LONG(size);
+ return size;
+}
+
+/*
+ * call-seq: size
+ *
+ * Get the size of this pointer.
+ */
+static VALUE
+rb_fiddle_ptr_size_get(VALUE self)
+{
+ return LONG2NUM(RPTR_DATA(self)->size);
+}
+
+/*
+ * call-seq:
+ * Fiddle::Pointer.to_ptr(val) => cptr
+ * Fiddle::Pointer[val] => cptr
+ *
+ * Get the underlying pointer for ruby object +val+ and return it as a
+ * Fiddle::Pointer object.
+ */
+static VALUE
+rb_fiddle_ptr_s_to_ptr(VALUE self, VALUE val)
+{
+ VALUE ptr, wrap = val, vptr;
+
+ if (RTEST(rb_obj_is_kind_of(val, rb_cIO))){
+ rb_io_t *fptr;
+ FILE *fp;
+ GetOpenFile(val, fptr);
+ fp = rb_io_stdio_file(fptr);
+ ptr = rb_fiddle_ptr_new(fp, 0, NULL);
+ }
+ else if (RTEST(rb_obj_is_kind_of(val, rb_cString))){
+ char *str = StringValuePtr(val);
+ ptr = rb_fiddle_ptr_new(str, RSTRING_LEN(val), NULL);
+ }
+ else if ((vptr = rb_check_funcall(val, id_to_ptr, 0, 0)) != Qundef){
+ if (rb_obj_is_kind_of(vptr, rb_cPointer)){
+ ptr = vptr;
+ wrap = 0;
+ }
+ else{
+ rb_raise(rb_eFiddleError, "to_ptr should return a Fiddle::Pointer object");
+ }
+ }
+ else{
+ VALUE num = rb_Integer(val);
+ if (num == val) wrap = 0;
+ ptr = rb_fiddle_ptr_new(NUM2PTR(num), 0, NULL);
+ }
+ OBJ_INFECT(ptr, val);
+ if (wrap) RPTR_DATA(ptr)->wrap[0] = wrap;
+ return ptr;
+}
+
+void
+Init_fiddle_pointer(void)
+{
+ id_to_ptr = rb_intern("to_ptr");
+
+ /* Document-class: Fiddle::Pointer
+ *
+ * Fiddle::Pointer is a class to handle C pointers
+ *
+ */
+ rb_cPointer = rb_define_class_under(mFiddle, "Pointer", rb_cObject);
+ rb_define_alloc_func(rb_cPointer, rb_fiddle_ptr_s_allocate);
+ rb_define_singleton_method(rb_cPointer, "malloc", rb_fiddle_ptr_s_malloc, -1);
+ rb_define_singleton_method(rb_cPointer, "to_ptr", rb_fiddle_ptr_s_to_ptr, 1);
+ rb_define_singleton_method(rb_cPointer, "[]", rb_fiddle_ptr_s_to_ptr, 1);
+ rb_define_method(rb_cPointer, "initialize", rb_fiddle_ptr_initialize, -1);
+ rb_define_method(rb_cPointer, "free=", rb_fiddle_ptr_free_set, 1);
+ rb_define_method(rb_cPointer, "free", rb_fiddle_ptr_free_get, 0);
+ rb_define_method(rb_cPointer, "to_i", rb_fiddle_ptr_to_i, 0);
+ rb_define_method(rb_cPointer, "to_int", rb_fiddle_ptr_to_i, 0);
+ rb_define_method(rb_cPointer, "to_value", rb_fiddle_ptr_to_value, 0);
+ rb_define_method(rb_cPointer, "ptr", rb_fiddle_ptr_ptr, 0);
+ rb_define_method(rb_cPointer, "+@", rb_fiddle_ptr_ptr, 0);
+ rb_define_method(rb_cPointer, "ref", rb_fiddle_ptr_ref, 0);
+ rb_define_method(rb_cPointer, "-@", rb_fiddle_ptr_ref, 0);
+ rb_define_method(rb_cPointer, "null?", rb_fiddle_ptr_null_p, 0);
+ rb_define_method(rb_cPointer, "to_s", rb_fiddle_ptr_to_s, -1);
+ rb_define_method(rb_cPointer, "to_str", rb_fiddle_ptr_to_str, -1);
+ rb_define_method(rb_cPointer, "inspect", rb_fiddle_ptr_inspect, 0);
+ rb_define_method(rb_cPointer, "<=>", rb_fiddle_ptr_cmp, 1);
+ rb_define_method(rb_cPointer, "==", rb_fiddle_ptr_eql, 1);
+ rb_define_method(rb_cPointer, "eql?", rb_fiddle_ptr_eql, 1);
+ rb_define_method(rb_cPointer, "+", rb_fiddle_ptr_plus, 1);
+ rb_define_method(rb_cPointer, "-", rb_fiddle_ptr_minus, 1);
+ rb_define_method(rb_cPointer, "[]", rb_fiddle_ptr_aref, -1);
+ rb_define_method(rb_cPointer, "[]=", rb_fiddle_ptr_aset, -1);
+ rb_define_method(rb_cPointer, "size", rb_fiddle_ptr_size_get, 0);
+ rb_define_method(rb_cPointer, "size=", rb_fiddle_ptr_size_set, 1);
+
+ /* Document-const: NULL
+ *
+ * A NULL pointer
+ */
+ rb_define_const(mFiddle, "NULL", rb_fiddle_ptr_new(0, 0, 0));
+}
generated by cgit v1.2.3 (git 2.25.1) at 2024-04-19 21:01:31 +0000