console_board.c

Go to the documentation of this file.

/*
 * Asterisk -- An open source telephony toolkit.
 *
 * Copyright 2007-2008, Marta Carbone, Luigi Rizzo
 *
 * See http://www.asterisk.org for more information about
 * the Asterisk project. Please do not directly contact
 * any of the maintainers of this project for assistance;
 * the project provides a web site, mailing lists and IRC
 * channels for your use.
 *
 * This program is free software, distributed under the terms of
 * the GNU General Public License Version 2. See the LICENSE file
 * at the top of the source tree.
 *
 * $Revision$
 */

/*
 * Message board implementation.
 *
 * A message board is a region of the SDL screen where
 * messages can be printed, like on a terminal window.
 *
 * At the moment we support fix-size font.
 *
 * The text is stored in a buffer
 * of fixed size (rows and cols). A portion of the buffer is
 * visible on the screen, and the visible window can be moved up and
 * down by dragging (not yet!)
 *
 * TODO: font dynamic allocation
 *
 * The region where the text is displayed on the screen is defined
 * as keypad element, (the name is defined in the `region' variable
 * so the board geometry can be read from the skin or from the
 * configuration file).
 */

/*** MODULEINFO
   <support_level>extended</support_level>
 ***/

#include "asterisk.h"   /* ast_strdupa */
#include "asterisk/utils.h"   /* ast_strdupa */
#include "console_video.h" /* ast_strdupa */

#ifdef HAVE_SDL   /* we only use this code if SDL is available */
#include <SDL/SDL.h>

/* Fonts characterization. XXX should be read from the file */
#define FONT_H 20       /* char height, pixels */
#define FONT_W 9        /* char width, pixels */

struct board {
   int      kb_output;  /* identity of the board */
   /* pointer to the destination surface (on the keypad window) */
   SDL_Surface *screen; /* the main screen */
   SDL_Rect *p_rect; /* where to write on the main screen */
   SDL_Surface *blank;     /* original content of the window */

   int   v_h;  /* virtual text height, in lines */
   int   v_w;  /* virtual text width, in lines (probably same as p_w) */
   int   p_h;  /* physical (displayed) text height, in lines
          * XXX p_h * FONT_H = pixel_height */
   int   p_w;  /* physical (displayed) text width, in characters
          * XXX p_w * FONT_W = pixel_width */

   int   cur_col; /* print position (free character) on the last line */
   int   cur_line;   /* first (or last ?) virtual line displayed,
                * 0 is the line at the bottom, 1 is the one above,...
                */

   SDL_Surface     *font;     /* points to a surface in the gui structure */
   SDL_Rect *font_rects;   /* pointer to the font rects */
   char     *text;
            /* text buffer, v_h * v_w char.
             * We make sure the buffer is always full,
             * print on some position on the last line,
             * and scroll up when appending new text
             */
};

/*! \brief Initialize the board.
 * return 0 on success, 1 on error
 * TODO, if this is done at reload time,
 * free resources before allocate new ones
 * TODO: resource deallocation in case of error.
 * TODO: move the font load at gui_initialization
 * TODO: deallocation of the message history
 */
struct board *board_setup(SDL_Surface *screen, SDL_Rect *dest,
   SDL_Surface *font, SDL_Rect *font_rects);
struct board *board_setup(SDL_Surface *screen, SDL_Rect *dest,
   SDL_Surface *font, SDL_Rect *font_rects)
{
   struct board *b = ast_calloc(1, sizeof (*b));
   SDL_Rect br;

   if (b == NULL)
      return NULL;
   /* font, points to the gui structure */
   b->font = font;
   b->font_rects = font_rects;

   /* Destination rectangle on the screen - reference is the whole screen */
   b->p_rect = dest;
   b->screen = screen;

   /* compute physical sizes */
   b->p_h = b->p_rect->h/FONT_H;
   b->p_w = b->p_rect->w/FONT_W;

   /* virtual sizes */
   b->v_h = b->p_h * 10; /* XXX 10 times larger */
   b->v_w = b->p_w;  /* same width */

   /* the rectangle we actually use */
   br.h = b->p_h * FONT_H; /* pixel sizes of the background */
   br.w = b->p_w * FONT_W;
   br.x = br.y = 0;

   /* allocate a buffer for the text */
   b->text = ast_calloc(b->v_w*b->v_h + 1, 1);
   if (b->text == NULL) {
      ast_log(LOG_WARNING, "Unable to allocate board history memory.\n");
      ast_free(b);
      return NULL;
   }
   memset(b->text, ' ', b->v_w * b->v_h); /* fill with spaces */

   /* make a copy of the original rectangle, for cleaning up */
   b->blank = SDL_CreateRGBSurface(screen->flags, br.w, br.h,
      screen->format->BitsPerPixel,
      screen->format->Rmask, screen->format->Gmask,
      screen->format->Bmask, screen->format->Amask);

   if (b->blank == NULL) {
      ast_log(LOG_WARNING, "Unable to allocate board virtual screen: %s\n",
            SDL_GetError());
      ast_free(b->text);
      ast_free(b);
      return NULL;
   }
   SDL_BlitSurface(screen, b->p_rect, b->blank, &br);

   /* Set color key, if not alpha channel present */
   //colorkey = SDL_MapRGB(b->board_surface->format, 0, 0, 0);
   //SDL_SetColorKey(b->board_surface, SDL_SRCCOLORKEY, colorkey);

   b->cur_col = 0;      /* current print column */
   b->cur_line = 0;  /* last line displayed */

   if (0) ast_log(LOG_WARNING, "Message board %dx%d@%d,%d successfully initialized\n",
      b->p_rect->w, b->p_rect->h,
      b->p_rect->x, b->p_rect->y);
   return b;
}

/* Render the text on the board surface.
 * The first line to render is the one at v_h - p_h - cur_line,
 * the size is p_h * p_w.
 * XXX we assume here that p_w = v_w.
 */
static void render_board(struct board *b)
{
   int first_row = b->v_h - b->p_h - b->cur_line;
   int first_char = b->v_w * first_row;
   int last_char = first_char + b->p_h * b->v_w;
   int i, col;
   SDL_Rect dst;

   /* top left char on the physical surface */
   dst.w = FONT_W;
   dst.h = FONT_H;
   dst.x = b->p_rect->x;
   dst.y = b->p_rect->y;


   /* clean the surface board */
   SDL_BlitSurface(b->blank, NULL, b->screen, b->p_rect);

   /* blit all characters */
   for (i = first_char, col = 0; i <  last_char; i++) {
      int c = b->text[i] - 32;   /* XXX first 32 chars are not printable */
      if (c < 0) /* buffer terminator or anything else is a blank */
         c = 0;
      SDL_BlitSurface(b->font, &b->font_rects[c], b->screen, &dst);
      /* point dst to next char position */
      dst.x += dst.w;
      col++;
      if (col >= b->v_w) { /* next row */
         dst.x = b->p_rect->x;
         dst.y += dst.h;
         col = 0;
      }
   }
   SDL_UpdateRects(b->screen, 1, b->p_rect); /* Update the screen */
}

void move_message_board(struct board *b, int dy)
{
   int cur = b->cur_line + dy;
   if (cur < 0)
      cur = 0;
   else if (cur >= b->v_h - b->p_h)
      cur = b->v_h - b->p_h - 1;
   b->cur_line = cur;
   render_board(b);
}

/* return the content of a board */
const char *read_message(const struct board *b)
{
   return b->text;
}

int reset_board(struct board *b)
{
   memset(b->text, ' ', b->v_w * b->v_h); /* fill with spaces */
   b->cur_col = 0;
   b->cur_line = 0;
   render_board(b);
   return 0;
}
/* Store the message on the history board
 * and blit on screen if required.
 * XXX now easy. only regular chars
 */
int print_message(struct board *b, const char *s)
{
   int i, l, row, col;
   char *dst;

   if (ast_strlen_zero(s))
      return 0;

   l = strlen(s);
   row = 0;
   col = b->cur_col;
   /* First, only check how much space we need.
    * Starting from the current print position, we move
    * it forward and down (if necessary) according to input
    * characters (including newlines, tabs, backspaces...).
    * At the end, row tells us how many rows to scroll, and
    * col (ignored) is the final print position.
    */
   for (i = 0; i < l; i++) {
      switch (s[i]) {
      case '\r':
         col = 0;
         break;
      case '\n':
         col = 0;
         row++;
         break;
      case '\b':
         if (col > 0)
            col--;
         break;
      default:
         if (s[i] < 32) /* signed, so take up to 127 */
            break;
         col++;
         if (col >= b->v_w) {
            col -= b->v_w;
            row++;
         }
         break;
      }
   }
   /* scroll the text window */
   if (row > 0) { /* need to scroll by 'row' rows */
      memcpy(b->text, b->text + row * b->v_w, b->v_w * (b->v_h - row));
      /* clean the destination area */
      dst = b->text + b->v_w * (b->v_h - row - 1) + b->cur_col;
      memset(dst, ' ', b->v_w - b->cur_col + b->v_w * row);
   }
   /* now do the actual printing. The print position is 'row' lines up
    * from the bottom of the buffer, start at the same 'cur_col' as before.
    * dst points to the beginning of the current line.
    */
   dst = b->text + b->v_w * (b->v_h - row - 1); /* start of current line */
   col = b->cur_col;
   for (i = 0; i < l; i++) {
      switch (s[i]) {
      case '\r':
         col = 0;
         break;
      case '\n':  /* move to beginning of next line */
         dst[col] = '\0'; /* mark the rest of the line as empty */
         col = 0;
         dst += b->v_w;
         break;
      case '\b':  /* one char back */
         if (col > 0)
            col--;
         dst[col] = ' '; /* delete current char */
         break;
      default:
         if (s[i] < 32) /* signed, so take up to 127 */
            break;   /* non printable */
         dst[col] = s[i];  /* store character */
         col++;
         if (col >= b->v_w) {
            col -= b->v_w;
            dst += b->v_w;
         }
         break;
      }
   }
   dst[col] = '\0'; /* the current position is empty */
   b->cur_col = col;
   /* everything is printed now, must do the rendering */
   render_board(b);
   return 1;
}

/* deletes a board.
 * we make the free operation on any fields of the board structure allocated
 * in dynamic memory
 */
void delete_board(struct board *b)
{
   if (b) {
      /* deletes the text */
      if (b->text)
         ast_free (b->text);
      /* deallocates the blank surface */
      SDL_FreeSurface(b->blank);
      /* deallocates the board */
      ast_free(b);
   }
}

#if 0
/*! \brief refresh the screen, and also grab a bunch of events.
 */
static int scroll_message(...)
{
if moving up, scroll text up;
    if (gui->message_board.screen_cur > 0)
   gui->message_board.screen_cur--;
otherwise scroll text down.
    if ((b->screen_cur + b->p_line) < b->board_next) {
   gui->message_board.screen_cur++;
#endif /* notyet */

#endif /* HAVE_SDL */