HelenOS sources

root/uspace/lib/c/generic/stdio/sstream.c

/* [<][>][^][v][top][bottom][index][help] */

DEFINITIONS

This source file includes following definitions.
  1. stdio_str_read
  2. stdio_str_write
  3. stdio_str_flush
  4. __sstream_init
  5. __sstream_getpos

/*
 * Copyright (c) 2018 Jiri Svoboda
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * - Redistributions of source code must retain the above copyright
 *   notice, this list of conditions and the following disclaimer.
 * - Redistributions in binary form must reproduce the above copyright
 *   notice, this list of conditions and the following disclaimer in the
 *   documentation and/or other materials provided with the distribution.
 * - The name of the author may not be used to endorse or promote products
 *   derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

/** @addtogroup libc
 * @{
 */
/** @file
 */

#include <stdio.h>
#include <str.h>
#include <errno.h>
#include <adt/list.h>
#include <uchar.h>
#include "../private/stdio.h"
#include "../private/sstream.h"

static size_t stdio_str_read(void *, size_t, size_t, FILE *);
static size_t stdio_str_write(const void *, size_t, size_t, FILE *);
static int stdio_str_flush(FILE *);

static __stream_ops_t stdio_str_ops = {
        .read = stdio_str_read,
        .write = stdio_str_write,
        .flush = stdio_str_flush
};

/** Read from string stream. */
static size_t stdio_str_read(void *buf, size_t size, size_t nmemb, FILE *stream)
{
        size_t nread;
        char *cp = (char *)stream->arg;
        char *bp = (char *)buf;

        nread = 0;
        while (nread < size * nmemb) {
                if (*cp == '\0') {
                        stream->eof = true;
                        break;
                }

                bp[nread] = *cp;
                ++nread;
                ++cp;
                stream->arg = (void *)cp;
        }

        return (nread / size);
}

/** Write to string stream. */
static size_t stdio_str_write(const void *buf, size_t size, size_t nmemb,
    FILE *stream)
{
        return 0;
}

/** Flush string stream. */
static int stdio_str_flush(FILE *stream)
{
        return EOF;
}

/** Initialize string stream.
 *
 * @param str String used as backend for reading
 * @param stream Stream to initialize
 */
void __sstream_init(const char *str, FILE *stream)
{
        memset(stream, 0, sizeof(FILE));
        stream->ops = &stdio_str_ops;
        stream->arg = (void *)str;
}

/** Return current string stream position.
 *
 * @param stream String stream
 * @return Pointer into the backing string at the current position
 */
const char *__sstream_getpos(FILE *stream)
{
        assert(stream->ops == &stdio_str_ops);
        return (char *) stream->arg;
}

/** @}
 */

/* [<][>][^][v][top][bottom][index][help] */
HelenOS homepage, sources at GitHub