/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (the "License").
 * You may not use this file except in compliance with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */
/*
 * Copyright 2008 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

#include "streams_wide.h"
#include "streams_common.h"

#define WIDE_VBUF_SIZE  (64 * KILOBYTE)

#define SHELF_OCCUPIED  1
#define SHELF_VACANT    0
static int shelf = SHELF_VACANT;

/*
 * Wide character streams implementation
 *
 *   The wide character streams implementation is, for the most part, a
 *   reimplementation of the stdio streams implementation, using wide character
 *   string routines.  However, fgetws(3C) retains the newline that fgets(3C)
 *   discards while reading a complete line.  As a result, the wide character
 *   routines need to guard against coincidental exhaustion of the buffer, as
 *   well as overwriting the end-of-line character and correcting the
 *   l_data_length field.
 */

static int
stream_wide_prime(stream_t *str)
{
        stream_buffered_file_t *BF = &(str->s_type.BF);
        wchar_t *current_position;
        wchar_t *end_of_buffer;
        wchar_t *next_nl;

        ASSERT(!(str->s_status & STREAM_OUTPUT));
        ASSERT(str->s_status & STREAM_OPEN);

        if (str->s_status & STREAM_INSTANT && (str->s_buffer == NULL)) {
                str->s_buffer = xzmap(0, WIDE_VBUF_SIZE, PROT_READ |
                    PROT_WRITE, MAP_PRIVATE, 0);
                if (str->s_buffer == MAP_FAILED)
                        die(EMSG_MMAP);
                str->s_buffer_size = WIDE_VBUF_SIZE;
        }

        ASSERT(str->s_buffer != NULL);

        if (stream_is_primed(str)) {
                int shelf_state = shelf;

                ASSERT(str->s_current.l_data_length >= -1);
                (void) memcpy(str->s_buffer, str->s_current.l_data.wp,
                    (str->s_current.l_data_length + 1) * sizeof (wchar_t));
                str->s_current.l_data.wp = str->s_buffer;

                if ((str->s_current.l_data_length == -1 ||
                    shelf_state == SHELF_OCCUPIED ||
                    *(str->s_current.l_data.wp +
                    str->s_current.l_data_length) != L'\0') &&
                    SOP_FETCH(str) == NEXT_LINE_INCOMPLETE &&
                    shelf_state == SHELF_OCCUPIED)
                        die(EMSG_MEMORY);

                return (PRIME_SUCCEEDED);
        }

        stream_set(str, STREAM_PRIMED);

        current_position = (wchar_t *)str->s_buffer;
        /*LINTED ALIGNMENT*/
        end_of_buffer = (wchar_t *)((char *)str->s_buffer +
            str->s_buffer_size);

        trip_eof(BF->s_fp);
        if (!feof(BF->s_fp))
                (void) fgetws(current_position, end_of_buffer
                    - current_position, BF->s_fp);
        else {
                stream_set(str, STREAM_EOS_REACHED);
                stream_unset(str, STREAM_PRIMED);
                return (PRIME_FAILED_EMPTY_FILE);
        }

        str->s_current.l_data.wp = current_position;
        next_nl = xmemwchar(current_position, L'\n', end_of_buffer -
            current_position);
        if (next_nl == NULL) {
                warn(WMSG_NEWLINE_ADDED, str->s_filename);
                str->s_current.l_data_length = MIN(wslen(current_position),
                    end_of_buffer - current_position);
        } else {
                str->s_current.l_data_length = next_nl - current_position;
        }
        *(str->s_current.l_data.wp + str->s_current.l_data_length) = L'\0';

        str->s_current.l_collate.wp = NULL;
        str->s_current.l_collate_length = 0;

        __S(stats_incr_fetches());
        return (PRIME_SUCCEEDED);
}

static ssize_t
stream_wide_fetch(stream_t *str)
{
        ssize_t dist_to_buf_end;
        int ret_val;
        wchar_t *graft_pt;
        wchar_t *next_nl;

        ASSERT(str->s_status & STREAM_OPEN);
        ASSERT((str->s_status & STREAM_EOS_REACHED) == 0);

        graft_pt = str->s_current.l_data.wp + str->s_current.l_data_length + 1;

        if (shelf == SHELF_VACANT)
                str->s_current.l_data.wp = graft_pt;
        else if (str->s_current.l_data_length > -1)
                graft_pt--;

        dist_to_buf_end = str->s_buffer_size / sizeof (wchar_t) - (graft_pt -
            (wchar_t *)str->s_buffer);

        if (dist_to_buf_end <= 1) {
                str->s_current.l_data_length = -1;
                return (NEXT_LINE_INCOMPLETE);
        }

        if (fgetws(graft_pt, dist_to_buf_end, str->s_type.BF.s_fp) == NULL) {
                if (feof(str->s_type.BF.s_fp))
                        stream_set(str, STREAM_EOS_REACHED);
                else
                        die(EMSG_READ, str->s_filename);
        }

        trip_eof(str->s_type.BF.s_fp);
        if ((next_nl = xmemwchar(str->s_current.l_data.wp, L'\n',
            dist_to_buf_end)) == NULL) {
                str->s_current.l_data_length =
                    MIN(wslen(str->s_current.l_data.wp), dist_to_buf_end);
        } else {
                str->s_current.l_data_length = next_nl -
                    str->s_current.l_data.wp;
        }

        str->s_current.l_collate_length = 0;

        if (*(str->s_current.l_data.wp + str->s_current.l_data_length) !=
            L'\n') {
                if (!feof(str->s_type.BF.s_fp)) {
                        if (shelf == SHELF_OCCUPIED)
                                die(EMSG_MEMORY);

                        shelf = SHELF_OCCUPIED;
                        ret_val = NEXT_LINE_INCOMPLETE;
                        __S(stats_incr_shelves());
                } else {
                        stream_set(str, STREAM_EOS_REACHED);
                        warn(WMSG_NEWLINE_ADDED, str->s_filename);
                }
        } else {
                shelf = SHELF_VACANT;
                ret_val = NEXT_LINE_COMPLETE;
                *(str->s_current.l_data.wp + str->s_current.l_data_length) =
                    L'\0';
                __S(stats_incr_fetches());
        }

        return (ret_val);
}

ssize_t
stream_wide_fetch_overwrite(stream_t *str)
{
        ssize_t dist_to_buf_end;

        ASSERT(str->s_status & STREAM_OPEN);
        ASSERT((str->s_status & STREAM_EOS_REACHED) == 0);

        str->s_current.l_data.wp = str->s_buffer;
        dist_to_buf_end = str->s_buffer_size / sizeof (wchar_t);

        if (fgetws(str->s_current.l_data.wp, dist_to_buf_end,
            str->s_type.BF.s_fp) == NULL) {
                if (feof(str->s_type.BF.s_fp))
                        stream_set(str, STREAM_EOS_REACHED);
                else
                        die(EMSG_READ, str->s_filename);
        }

        trip_eof(str->s_type.BF.s_fp);
        str->s_current.l_data_length = wslen(str->s_current.l_data.wp) - 1;
        str->s_current.l_collate_length = 0;

        if (str->s_current.l_data_length == -1 ||
            *(str->s_current.l_data.wp + str->s_current.l_data_length) !=
            L'\n') {
                if (!feof(str->s_type.BF.s_fp)) {
                        die(EMSG_MEMORY);
                } else {
                        stream_set(str, STREAM_EOS_REACHED);
                        warn(WMSG_NEWLINE_ADDED, str->s_filename);
                        str->s_current.l_data_length++;
                }
        }

        *(str->s_current.l_data.wp + str->s_current.l_data_length) = L'\0';

        __S(stats_incr_fetches());
        return (NEXT_LINE_COMPLETE);
}

static void
stream_wide_send_eol(stream_t *str)
{
        wchar_t w_crlf[2] = { L'\n', L'\0' };

        ASSERT(str->s_status & STREAM_OPEN);
        ASSERT(str->s_status & STREAM_OUTPUT);

        if (wxwrite(str->s_type.SF.s_fd, w_crlf) < 0)
                die(EMSG_WRITE, str->s_filename);
}

static void
stream_wide_put_line(stream_t *str, line_rec_t *line)
{
        ASSERT(str->s_status & STREAM_OPEN);
        ASSERT(str->s_status & STREAM_OUTPUT);

        if (line->l_data_length >= 0) {
                if (wxwrite(str->s_type.SF.s_fd, line->l_data.wp) >= 0) {
                        stream_wide_send_eol(str);
                        __S(stats_incr_puts());
                } else
                        die(EMSG_WRITE, str->s_filename);
        }
        safe_free(line->l_raw_collate.wp);
        line->l_raw_collate.wp = NULL;
}

void
stream_wide_put_line_unique(stream_t *str, line_rec_t *line)
{
        static line_rec_t pvs;
        static size_t collate_buf_len;

        ASSERT(str->s_status & STREAM_OPEN);
        ASSERT(str->s_status & STREAM_OUTPUT);

        if ((pvs.l_collate.sp == NULL ||
            collated_wide(&pvs, line, 0, COLL_UNIQUE) != 0) &&
            line->l_data_length >= 0) {
                stream_wide_put_line(str, line);

                if (line->l_collate_length + sizeof (wchar_t) >
                    collate_buf_len) {
                        pvs.l_collate.sp = safe_realloc(pvs.l_collate.sp,
                            line->l_collate_length + sizeof (wchar_t));
                        collate_buf_len = line->l_collate_length +
                            sizeof (wchar_t);
                }

                (void) memcpy(pvs.l_collate.sp, line->l_collate.sp,
                    line->l_collate_length);
                /* LINTED ALIGNMENT */
                *(wchar_t *)(pvs.l_collate.sp + line->l_collate_length) = L'\0';
                pvs.l_collate_length = line->l_collate_length;
        }
}

static int
stream_wide_eos(stream_t *str)
{
        int retval = 0;

        if (str == NULL || str->s_status & STREAM_EOS_REACHED)
                return (1);

        trip_eof(str->s_type.BF.s_fp);
        if (feof(str->s_type.BF.s_fp) &&
            shelf == SHELF_VACANT &&
            str->s_current.l_collate_length != -1) {
                retval = 1;
                stream_set(str, STREAM_EOS_REACHED);
        }

        return (retval);
}

/*ARGSUSED*/
static void
stream_wide_release_line(stream_t *str)
{
}

const stream_ops_t stream_wide_ops = {
        stream_stdio_is_closable,
        stream_stdio_close,
        stream_wide_eos,
        stream_wide_fetch,
        stream_stdio_flush,
        stream_stdio_free,
        stream_stdio_open_for_write,
        stream_wide_prime,
        stream_wide_put_line,
        stream_wide_release_line,
        stream_wide_send_eol,
        stream_stdio_unlink
};