handle.pmc

/*
Copyright (C) 2008-2010, Parrot Foundation.

=head1 NAME

src/pmc/handle.pmc - IO Handle PMC

=head1 DESCRIPTION

This is the base-class for all IO-related PMCs.

=head2 Vtable Functions

=over 4

=item C<init>

=item C<init_pmc>

Handle shouldn't be directly instantiated, init and init_pmc throws
EXCEPTION_INVALID_OPERATION.

=cut

*/

#include "parrot/parrot.h"
#include "../src/io/io_private.h"

/* HEADERIZER HFILE: none */
/* HEADERIZER BEGIN: static */
/* HEADERIZER END: static */

pmclass Handle provides Handle manual_attrs {
    /* TODO: Consider encapsulating PIOHANDLE as a PMC type, for subclassing */
    ATTR PIOHANDLE os_handle;           /* Low level OS descriptor */
    ATTR STRING    *record_separator;   /* Record separator */
    ATTR IO_VTABLE *io_vtable;          /* Function dispatch table */
    ATTR IO_BUFFER *read_buffer;        /* Read Buffer */
    ATTR IO_BUFFER *write_buffer;       /* Write Buffer */
    ATTR STRING *encoding;              /* The encoding for read/write  */


    VTABLE void init() {
        Parrot_ex_throw_from_c_args(INTERP, NULL, EXCEPTION_INVALID_OPERATION,
            "Handle cannot be instantiated directly.");
    }

    VTABLE void init_pmc(PMC * init) {
        Parrot_ex_throw_from_c_args(INTERP, NULL, EXCEPTION_INVALID_OPERATION,
            "Handle cannot be instantiated directly.");
    }

    VTABLE void *get_pointer_keyed_int(INTVAL key)
    {
        void * ptr;
        switch (key) {
            case IO_PTR_IDX_VTABLE:
                GET_ATTR_io_vtable(INTERP, SELF, ptr);
                break;
            case IO_PTR_IDX_READ_BUFFER:
                GET_ATTR_read_buffer(INTERP, SELF, ptr);
                break;
            case IO_PTR_IDX_WRITE_BUFFER:
                GET_ATTR_write_buffer(INTERP, SELF, ptr);
                break;
            default:
                Parrot_ex_throw_from_c_args(INTERP, NULL, EXCEPTION_PIO_ERROR,
                    "Handle: Cannot get pointer %d", key);
        }
        return ptr;
    }

    VTABLE void set_pointer_keyed_int(INTVAL key, void *ptr)
    {
        switch (key) {
            case IO_PTR_IDX_VTABLE:
                SET_ATTR_io_vtable(INTERP, SELF, (IO_VTABLE *)ptr);
                break;
            case IO_PTR_IDX_READ_BUFFER:
                SET_ATTR_read_buffer(INTERP, SELF, (IO_BUFFER *)ptr);
                break;
            case IO_PTR_IDX_WRITE_BUFFER:
                SET_ATTR_write_buffer(INTERP, SELF, (IO_BUFFER *)ptr);
                break;
            default:
                Parrot_ex_throw_from_c_args(INTERP, NULL, EXCEPTION_PIO_ERROR,
                    "Handle: Cannot set pointer %d", key);
        }
    }

/*

=back

=head2 Methods

=over 4

=item C<METHOD isatty()>

Returns a boolean value indicating whether C<SELF> is a console/tty.
This default implementation always return false. Override it in
subtypes that are or can be tty.

=cut

*/

    METHOD isatty() {
        RETURN(INTVAL 0);
    }

/*

=item C<METHOD get_fd()>

Retrieve the integer file descriptor for the Handle (only available on
platforms that use integer file descriptors).

=cut

*/

    METHOD get_fd() {
        PIOHANDLE os_handle;
        INTVAL    fd;
        GET_ATTR_os_handle(INTERP, SELF, os_handle);
        fd = (INTVAL)os_handle;
        RETURN(INTVAL fd);
    }


/*

=item C<METHOD read(INTVAL bytes)>

Read the given number of bytes from the handle and return them in a string.

=cut

*/

    METHOD read(INTVAL length) {
        STRING * const string_result = Parrot_io_reads(INTERP, SELF, length);
        RETURN(STRING *string_result);
    }


/*

=item C<METHOD readline()>

Read a line from the handle and return it in a string.

=cut

*/

    METHOD readline(STRING * record_separator :optional, INTVAL has_rs :opt_flag) {
        STRING * string_result;
        if (!has_rs) {
            GET_ATTR_record_separator(interp, SELF, record_separator);
        }
        string_result = Parrot_io_readline_s(INTERP, SELF, record_separator);
        RETURN(STRING *string_result);
    }

/*

=item C<METHOD read_bytes(INTVAL bytes)>

Read the given number of bytes from the handle and return them in a
ByteBuffer.

=cut

*/

    METHOD read_bytes(INTVAL length) {
        PMC * const bb = Parrot_io_read_byte_buffer_pmc(INTERP, SELF, PMCNULL, length);
        RETURN(PMC *bb);
    }

    METHOD write_bytes(PMC *bytebuffer, INTVAL length) {
        const INTVAL written = Parrot_io_write_byte_buffer_pmc(INTERP, SELF, bytebuffer, length);
        RETURN(INTVAL written);
    }


/*

=item C<METHOD record_separator()>

Set the record separator for readline.

=cut

*/

    METHOD record_separator(STRING *str :optional, int has_str :opt_flag) {
        if (has_str) {
            if (STRING_IS_NULL(str))
                Parrot_ex_throw_from_c_args(INTERP, NULL, EXCEPTION_INVALID_OPERATION,
                    "Record separator may not be null");

            str = Parrot_io_reencode_string_for_handle(INTERP, SELF, str);
            SET_ATTR_record_separator(INTERP, SELF, str);
        }
        else {
            GET_ATTR_record_separator(INTERP, SELF, str);
        }

        RETURN(STRING *str);
    }


/*

=item C<METHOD close()>

Close the handle.

=cut

*/

    METHOD close() {
        const INTVAL status = Parrot_io_close(INTERP, SELF, 1);
        RETURN(INTVAL status);
    }

/*

=item C<METHOD encoding(STRING *new_encoding)>

Set or retrieve the encoding attribute (a string name of the selected encoding
scheme) for the filehandle.

=cut

*/

    METHOD encoding(STRING *encoding :optional, INTVAL got_encoding :opt_flag) {
        if (got_encoding) {
            STRING * record_separator;

            SET_ATTR_encoding(INTERP, SELF, encoding);
            GET_ATTR_record_separator(INTERP, SELF, record_separator);
            record_separator = Parrot_io_reencode_string_for_handle(INTERP, SELF, record_separator);
            SET_ATTR_record_separator(INTERP, SELF, record_separator);
        }
        else {
            GET_ATTR_encoding(INTERP, SELF, encoding);
        }
        RETURN(STRING *encoding);
    }
}

/*
 * Local variables:
 *   c-file-style: "parrot"
 * End:
 * vim: expandtab shiftwidth=4 cinoptions='\:2=2' :
 */