source: neercs/trunk/src/client.c Tweet

/*
 *  neercs        console-based window manager
 *  Copyright (c) 2006-2010 Sam Hocevar <sam@hocevar.net>
 *                2008-2010 Jean-Yves Lamoureux <jylam@lnxscene.org>
 *                2008-2011 Pascal Terjan <pterjan@linuxfr.org>
 *                All Rights Reserved
 *
 *  This program is free software. It comes without any warranty, to
 *  the extent permitted by applicable law. You can redistribute it
 *  and/or modify it under the terms of the Do What The Fuck You Want
 *  To Public License, Version 2, as published by Sam Hocevar. See
 *  http://sam.zoy.org/wtfpl/COPYING for more details.
 */

#include "config.h"

#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <unistd.h>
#include <fcntl.h>
#include <signal.h>
#include <sys/ioctl.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <sys/time.h>
#include <time.h>
#include <pwd.h>

#include <errno.h>
#include <caca.h>

#include "neercs.h"

#define NEERCS_RECV_BUFSIZE 128*1024


int start_client(struct screen_list *screen_list)
{
    char *sess = NULL;
    create_socket(screen_list, SOCK_CLIENT);
    while ((sess = connect_socket(screen_list, SOCK_SERVER)) == NULL)
        usleep(100);
    free(sess);

    /* Create main canvas and associated caca window */
    screen_list->cv = caca_create_canvas(0, 0);
    screen_list->dp = caca_create_display(screen_list->cv);
    screen_list->mouse_button = 0;

    if (!screen_list->dp)
        return -3;

    caca_set_display_time(screen_list->dp, screen_list->delay * 1000);
    caca_set_cursor(screen_list->dp, 1);

    request_attach(screen_list);

    return 0;
}

int send_event(caca_event_t ev, struct screen_list *screen_list)
{
    enum caca_event_type t;
    char buf[64];
    int bytes = 0;

    t = caca_get_event_type(&ev);

    if (t & CACA_EVENT_KEY_PRESS)
    {
        bytes =  snprintf(buf, sizeof(buf) - 1, "KEY %d",
                          caca_get_event_key_ch(&ev));
        debug("Sending key press to server: %s", buf);
    }
    else if (t & CACA_EVENT_RESIZE)
    {
        bytes = snprintf(buf, sizeof(buf) - 1, "RESIZE %10d %10d",
                         caca_get_event_resize_width(&ev),
                         caca_get_event_resize_height(&ev));
    }
    else if (t & CACA_EVENT_MOUSE_PRESS)
    {
        screen_list->mouse_button = caca_get_event_mouse_button(&ev);
        bytes = snprintf(buf, sizeof(buf) - 1, "MOUSEP %10d %10d %10d",
                         caca_get_mouse_x(screen_list->dp),
                         caca_get_mouse_y(screen_list->dp),
                         screen_list->mouse_button);
    }
    else if (t & CACA_EVENT_MOUSE_RELEASE)
    {
        bytes = snprintf(buf, sizeof(buf) - 1, "MOUSER %10d %10d %10d",
                         caca_get_mouse_x(screen_list->dp),
                         caca_get_mouse_y(screen_list->dp),
                         screen_list->mouse_button);
        screen_list->mouse_button = 0;
    }
    else if (t & CACA_EVENT_MOUSE_MOTION)
    {
        int x = caca_get_mouse_x(screen_list->dp);
        int y = caca_get_mouse_y(screen_list->dp);
        int b = screen_list->mouse_button;
        debug("Mouse motion, button %d", b);
        if (x != screen_list->old_x || y != screen_list->old_y)
        {
            screen_list->old_x = caca_get_mouse_x(screen_list->dp);
            screen_list->old_y = caca_get_mouse_y(screen_list->dp);

            bytes = snprintf(buf, sizeof(buf) - 1, "MOUSEM %10d %10d %10d",
                             caca_get_mouse_x(screen_list->dp),
                             caca_get_mouse_y(screen_list->dp),
                             b>=0?b:0);
        }
    }
    else if (t & CACA_EVENT_QUIT)
    {
        bytes = snprintf(buf, sizeof(buf) - 1, "QUIT");
    }
    if (bytes)
    {
        ssize_t r;
        buf[bytes] = '\0';
        debug("Sending '%s', %d bytes", buf, bytes);
        r = write(screen_list->comm.socket[SOCK_SERVER], buf, bytes+1);
        while (r < 0 && errno == EAGAIN)
        {
            usleep(20);
            r = write(screen_list->comm.socket[SOCK_SERVER], buf, bytes+1);
        }
        return r < 0;
    }
    return 0;
}

int send_delay(struct screen_list *screen_list)
{
    debug("Sending DELAY\n");
    char buf[18];
    int bytes;
    bytes = snprintf(buf, sizeof(buf) - 1, "DELAY %10d", screen_list->delay);
    buf[bytes] = '\0';
    return write(screen_list->comm.socket[SOCK_SERVER], buf, strlen(buf)) <= 0;
}

/** \brief Main client loop.
 *
 * This is the main client loop.
 *
 * Repeat forever:
 *  - if data is available on the client socket, read it and interpret it:
 *    - "DETACH": exit the loop
 *    - "UPDATE": update screen with the given canvas data
 *    - "REFRESH": refresh the whole display
 *    - "CURSOR": set cursor position
 *    - "TITLE": set window or display title
 *  - wait for an input event with a 10ms timeout
 */
void mainloop(struct screen_list *screen_list)
{
    char *buf = NULL;

    screen_list->last_key_time = get_us();

    for (;;)
    {
        caca_event_t ev;
        int ret = 0;
        ssize_t n;
        if (!screen_list)
            goto end;
        if (!buf)
            buf = malloc(NEERCS_RECV_BUFSIZE);
        if (!buf)
        {
            debug("Failed to allocate memory");
            goto end;
        }
        if (screen_list->comm.socket[SOCK_CLIENT]
            && (n =
                read(screen_list->comm.socket[SOCK_CLIENT], buf,
                     NEERCS_RECV_BUFSIZE - 1)) > 0)
        {
            buf[n] = 0;
            debug("Received from server: '%s' (%d bytes)", buf, n);
            if (!strncmp("DETACH", buf, 6))
            {
                /* ret = 1; Not used */
                break;
            }
            else if (!strncmp("UPDATE ", buf, 7))
            {
                int x, y;
                ssize_t l2 = 0, lb = 0;
                char *buf2;
                size_t l = 0;
                /* FIXME check the length before calling atoi */
                x = atoi(buf + 8);
                y = atoi(buf + 19);

                /* 0 means we have valid data but incomplete, so read the rest
                 */
                while (l == 0)
                {
                    buf2 = realloc(buf, l2 + NEERCS_RECV_BUFSIZE);
                    if (!buf2)
                    {
                        debug("Failed to allocate memory");
                        goto end;
                    }
                    buf = buf2;
                    fcntl(screen_list->comm.socket[SOCK_CLIENT], F_SETFL, 0);
                    lb = read(screen_list->comm.socket[SOCK_CLIENT], buf + l2,
                              NEERCS_RECV_BUFSIZE - 1);
                    if (lb < 0)
                    {
                        debug
                            ("Failed to read the end of the refresh message (%s)",
                             strerror(errno));
                        l = -1;
                    }
                    else
                    {
                        l2 += lb;
                        l = caca_import_area_from_memory(screen_list->cv, x, y,
                                                         buf, l2, "caca");
                    }
                }
                fcntl(screen_list->comm.socket[SOCK_CLIENT], F_SETFL,
                      O_NONBLOCK);
            }
            else if (!strncmp("REFRESH ", buf, 8))
            {
                int dt, x, y;
                /* FIXME check the length before calling atoi */
                x = atoi(buf + 8);
                y = atoi(buf + 19);
                caca_gotoxy(screen_list->cv, x, y);
                caca_refresh_display(screen_list->dp);
                dt = caca_get_display_time(screen_list->dp);

                /* Adjust refresh delay so that the server do not compute
                   useless things */
                if (dt > 2 * 1000 * screen_list->delay
                    && screen_list->delay <= 100)
                {
                    screen_list->delay *= 2;
                    send_delay(screen_list);
                }
                else if (dt < screen_list->delay * 1000 * 1.2 &&
                         screen_list->delay >=
                         3 * screen_list->requested_delay / 2)
                {
                    screen_list->delay = 2 * screen_list->delay / 3;
                    send_delay(screen_list);
                }
                screen_list->comm.attached = 1;
            }
            else if (!strncmp("CURSOR ", buf, 7))
            {
                caca_set_cursor(screen_list->dp, atoi(buf + 7));
            }
            else if (!strncmp("TITLE ", buf, 6))
            {
                caca_set_display_title(screen_list->dp, buf + 6);
                caca_refresh_display(screen_list->dp);
            }
            else
            {
                debug("Unknown message received from server: %s", buf);
            }
        }

        /* Wait to have finished attaching before handling events */
        if (screen_list->comm.attached)
        {
           ret = caca_get_event(screen_list->dp,
                                CACA_EVENT_KEY_PRESS
                                | CACA_EVENT_MOUSE_PRESS
                                | CACA_EVENT_MOUSE_RELEASE
                                | CACA_EVENT_MOUSE_MOTION
                                | CACA_EVENT_RESIZE
                                | CACA_EVENT_QUIT, &ev, 10000);
           if (ret)
               ret = send_event(ev, screen_list);
           if (ret)
           {
               debug("Failed send event, quitting: %s\n", strerror(errno));
               break;
           }
        }
    }

  end:
    if (buf)
        free(buf);

}