source: mainline/uspace/lib/libc/generic/io/stream.c@ 975f62f

/*
 * Copyright (c) 2006 Josef Cejka
 * Copyright (c) 2006 Jakub Vana
 * 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 <io/io.h>
#include <io/stream.h>
#include <string.h>
#include <malloc.h>
#include <libc.h>
#include <ipc/ipc.h>
#include <ipc/ns.h>
#include <ipc/fb.h>
#include <ipc/services.h>
#include <console.h>
#include <unistd.h>
#include <async.h>

#define FDS 32

typedef struct stream_t {
        pwritefn_t w;
        preadfn_t r;
        void * param;
        int phone;
} stream_t;

static int console_phone = -1;
static stream_t streams[FDS];

static ssize_t write_stderr(void *param, const void *buf, size_t count)
{
        return count;
}

static ssize_t read_stdin(void *param, void *buf, size_t count)
{
        ipcarg_t r0, r1;
        size_t i = 0;

        while (i < count) {
                if (async_req_2(streams[0].phone, CONSOLE_GETCHAR, 0, 0, &r0,
                    &r1) < 0) {
                        return -1;
                }
                ((char *) buf)[i++] = r0;
        }
        return i;
}

static ssize_t write_stdout(void *param, const void *buf, size_t count)
{
        int i;

        for (i = 0; i < count; i++)
                async_msg(streams[1].phone, CONSOLE_PUTCHAR,
                    ((const char *) buf)[i]);
        
        return count;
}

static stream_t open_stdin(void)
{
        stream_t stream;
        
        if (console_phone < 0) {
                while ((console_phone = ipc_connect_me_to(PHONE_NS,
                    SERVICE_CONSOLE, 0)) < 0) {
                        usleep(10000);
                }
        }
        
        stream.r = read_stdin;
        stream.w = NULL;
        stream.param = 0;
        stream.phone = console_phone;
        
        return stream;
}

static stream_t open_stdout(void)
{
        stream_t stream;

        if (console_phone < 0) {
                while ((console_phone = ipc_connect_me_to(PHONE_NS,
                    SERVICE_CONSOLE, 0)) < 0) {
                        usleep(10000);
                }
        }
        
        stream.r = NULL;
        stream.w = write_stdout;
        stream.phone = console_phone;
        stream.param = 0;
        
        return stream;
}

static ssize_t write_null(void *param, const void *buf, size_t count)
{
        return count;
}

fd_t open(const char *fname, int flags)
{
        int c = 0;

        while (((streams[c].w) || (streams[c].r)) && (c < FDS))
                c++;
        
        if (c == FDS)
                return EMFILE;
        
        if (!strcmp(fname, "stdin")) {
                streams[c] = open_stdin();
                return c;
        }
        
        if (!strcmp(fname, "stdout")) {
                streams[c] = open_stdout();
                return c;
        }
        
        if (!strcmp(fname, "stderr")) {
                streams[c].w = write_stderr;
                return c;
        }
        
        if (!strcmp(fname, "null")) {
                streams[c].w = write_null;
                return c;
        }
        
        return -1;
}


ssize_t write(int fd, const void *buf, size_t count)
{
        if (fd < FDS && streams[fd].w)
                return streams[fd].w(streams[fd].param, buf, count);
        
        return 0;
}

ssize_t read(int fd, void *buf, size_t count)
{
        if (fd < FDS && streams[fd].r)
                return streams[fd].r(streams[fd].param, buf, count);
        
        return 0;
}

int get_fd_phone(int fd)
{
        if (fd >= FDS || fd < 0)
                return -1;
        return streams[fd].phone;
}

/** @}
 */