cache.c

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/* -*- c-basic-offset: 8 -*-
   rdesktop: A Remote Desktop Protocol client.
   Cache routines
   Copyright (C) Matthew Chapman 1999-2005
   Copyright (C) Jeroen Meijer 2005
 
   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 2 of the License, or
   (at your option) any later version.
 
   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.
 
   You should have received a copy of the GNU General Public License along
   with this program; if not, write to the Free Software Foundation, Inc.,
   51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
 
#include "rdesktop.h"
 
#undef IS_SET // !!!FIXME!!!
 
/* BITMAP CACHE */
#define NUM_ELEMENTS(array) (sizeof(array) / sizeof(array[0]))
#define IS_PERSISTENT(id) (This->pstcache_fd[id] > 0)
#define TO_TOP -1
#define NOT_SET -1
#define IS_SET(idx) (idx >= 0)
 
/*
 * TODO: Test for optimal value of BUMP_COUNT. TO_TOP gives lowest cpu utilisation but using
 * a positive value will hopefully result in less frequently used bitmaps having a greater chance
 * of being evicted from the cache, and therby reducing the need to load bitmaps from disk.
 * (Jeroen)
 */
#define BUMP_COUNT 40
 
/* Setup the bitmap cache lru/mru linked list */
void
cache_rebuild_bmpcache_linked_list(RDPCLIENT * This, uint8 id, sint16 * idx, int count)
{
    int n = count, c = 0;
    sint16 n_idx;
 
    /* find top, skip evicted bitmaps */
    while (--n >= 0 && This->cache.bmpcache[id][idx[n]].bitmap == NULL);
    if (n < 0)
    {
        This->cache.bmpcache_mru[id] = This->cache.bmpcache_lru[id] = NOT_SET;
        return;
    }
 
    This->cache.bmpcache_mru[id] = idx[n];
    This->cache.bmpcache[id][idx[n]].next = NOT_SET;
    n_idx = idx[n];
    c++;
 
    /* link list */
    while (n >= 0)
    {
        /* skip evicted bitmaps */
        while (--n >= 0 && This->cache.bmpcache[id][idx[n]].bitmap == NULL);
 
        if (n < 0)
            break;
 
        This->cache.bmpcache[id][n_idx].previous = idx[n];
        This->cache.bmpcache[id][idx[n]].next = n_idx;
        n_idx = idx[n];
        c++;
    }
 
    This->cache.bmpcache[id][n_idx].previous = NOT_SET;
    This->cache.bmpcache_lru[id] = n_idx;
 
    if (c != This->cache.bmpcache_count[id])
    {
        error("Oops. %d in bitmap cache linked list, %d in ui cache...\n", c,
              This->cache.bmpcache_count[id]);
        exit(1);
    }
}
 
/* Move a bitmap to a new position in the linked list. */
void
cache_bump_bitmap(RDPCLIENT * This, uint8 id, uint16 idx, int bump)
{
    int p_idx, n_idx, n;
 
    if (!IS_PERSISTENT(id))
        return;
 
    if (This->cache.bmpcache_mru[id] == idx)
        return;
 
    DEBUG_RDP5(("bump bitmap: id=%d, idx=%d, bump=%d\n", id, idx, bump));
 
    n_idx = This->cache.bmpcache[id][idx].next;
    p_idx = This->cache.bmpcache[id][idx].previous;
 
    if (IS_SET(n_idx))
    {
        /* remove */
        --This->cache.bmpcache_count[id];
        if (IS_SET(p_idx))
            This->cache.bmpcache[id][p_idx].next = n_idx;
        else
            This->cache.bmpcache_lru[id] = n_idx;
        if (IS_SET(n_idx))
            This->cache.bmpcache[id][n_idx].previous = p_idx;
        else
            This->cache.bmpcache_mru[id] = p_idx;
    }
    else
    {
        p_idx = NOT_SET;
        n_idx = This->cache.bmpcache_lru[id];
    }
 
    if (bump >= 0)
    {
        for (n = 0; n < bump && IS_SET(n_idx); n++)
        {
            p_idx = n_idx;
            n_idx = This->cache.bmpcache[id][p_idx].next;
        }
    }
    else
    {
        p_idx = This->cache.bmpcache_mru[id];
        n_idx = NOT_SET;
    }
 
    /* insert */
    ++This->cache.bmpcache_count[id];
    This->cache.bmpcache[id][idx].previous = p_idx;
    This->cache.bmpcache[id][idx].next = n_idx;
 
    if (p_idx >= 0)
        This->cache.bmpcache[id][p_idx].next = idx;
    else
        This->cache.bmpcache_lru[id] = idx;
 
    if (n_idx >= 0)
        This->cache.bmpcache[id][n_idx].previous = idx;
    else
        This->cache.bmpcache_mru[id] = idx;
}
 
/* Evict the least-recently used bitmap from the cache */
void
cache_evict_bitmap(RDPCLIENT * This, uint8 id)
{
    uint16 idx;
    int n_idx;
 
    if (!IS_PERSISTENT(id))
        return;
 
    idx = This->cache.bmpcache_lru[id];
    n_idx = This->cache.bmpcache[id][idx].next;
    DEBUG_RDP5(("evict bitmap: id=%d idx=%d n_idx=%d bmp=0x%x\n", id, idx, n_idx,
            This->cache.bmpcache[id][idx].bitmap));
 
    ui_destroy_bitmap(This, This->cache.bmpcache[id][idx].bitmap);
    --This->cache.bmpcache_count[id];
    This->cache.bmpcache[id][idx].bitmap = 0;
 
    This->cache.bmpcache_lru[id] = n_idx;
    This->cache.bmpcache[id][n_idx].previous = NOT_SET;
 
    pstcache_touch_bitmap(This, id, idx, 0);
}
 
/* Retrieve a bitmap from the cache */
HBITMAP
cache_get_bitmap(RDPCLIENT * This, uint8 id, uint16 idx)
{
    if ((id < NUM_ELEMENTS(This->cache.bmpcache)) && (idx < NUM_ELEMENTS(This->cache.bmpcache[0])))
    {
        if (This->cache.bmpcache[id][idx].bitmap || pstcache_load_bitmap(This, id, idx))
        {
            if (IS_PERSISTENT(id))
                cache_bump_bitmap(This, id, idx, BUMP_COUNT);
 
            return This->cache.bmpcache[id][idx].bitmap;
        }
    }
    else if ((id < NUM_ELEMENTS(This->cache.volatile_bc)) && (idx == 0x7fff))
    {
        return This->cache.volatile_bc[id];
    }
 
    error("get bitmap %d:%d\n", id, idx);
    return NULL;
}
 
/* Store a bitmap in the cache */
void
cache_put_bitmap(RDPCLIENT * This, uint8 id, uint16 idx, HBITMAP bitmap)
{
    HBITMAP old;
 
    if ((id < NUM_ELEMENTS(This->cache.bmpcache)) && (idx < NUM_ELEMENTS(This->cache.bmpcache[0])))
    {
        old = This->cache.bmpcache[id][idx].bitmap;
        if (old != NULL)
            ui_destroy_bitmap(This, old);
        This->cache.bmpcache[id][idx].bitmap = bitmap;
 
        if (IS_PERSISTENT(id))
        {
            if (old == NULL)
                This->cache.bmpcache[id][idx].previous = This->cache.bmpcache[id][idx].next = NOT_SET;
 
            cache_bump_bitmap(This, id, idx, TO_TOP);
            if (This->cache.bmpcache_count[id] > BMPCACHE2_C2_CELLS)
                cache_evict_bitmap(This, id);
        }
    }
    else if ((id < NUM_ELEMENTS(This->cache.volatile_bc)) && (idx == 0x7fff))
    {
        old = This->cache.volatile_bc[id];
        if (old != NULL)
            ui_destroy_bitmap(This, old);
        This->cache.volatile_bc[id] = bitmap;
    }
    else
    {
        error("put bitmap %d:%d\n", id, idx);
    }
}
 
/* Updates the persistent bitmap cache MRU information on exit */
void
cache_save_state(RDPCLIENT * This)
{
    uint32 id = 0, t = 0;
    int idx;
 
    for (id = 0; id < NUM_ELEMENTS(This->cache.bmpcache); id++)
        if (IS_PERSISTENT(id))
        {
            DEBUG_RDP5(("Saving cache state for bitmap cache %d...", id));
            idx = This->cache.bmpcache_lru[id];
            while (idx >= 0)
            {
                pstcache_touch_bitmap(This, id, idx, ++t);
                idx = This->cache.bmpcache[id][idx].next;
            }
            DEBUG_RDP5((" %d stamps written.\n", t));
        }
}
 
 
/* FONT CACHE */
/* Retrieve a glyph from the font cache */
FONTGLYPH *
cache_get_font(RDPCLIENT * This, uint8 font, uint16 character)
{
    FONTGLYPH *glyph;
 
    if ((font < NUM_ELEMENTS(This->cache.fontcache)) && (character < NUM_ELEMENTS(This->cache.fontcache[0])))
    {
        glyph = &This->cache.fontcache[font][character];
        if (glyph->pixmap != NULL)
            return glyph;
    }
 
    error("get font %d:%d\n", font, character);
    return NULL;
}
 
/* Store a glyph in the font cache */
void
cache_put_font(RDPCLIENT * This, uint8 font, uint16 character, uint16 offset,
           uint16 baseline, uint16 width, uint16 height, HGLYPH pixmap)
{
    FONTGLYPH *glyph;
 
    if ((font < NUM_ELEMENTS(This->cache.fontcache)) && (character < NUM_ELEMENTS(This->cache.fontcache[0])))
    {
        glyph = &This->cache.fontcache[font][character];
        if (glyph->pixmap != NULL)
            ui_destroy_glyph(This, glyph->pixmap);
 
        glyph->offset = offset;
        glyph->baseline = baseline;
        glyph->width = width;
        glyph->height = height;
        glyph->pixmap = pixmap;
    }
    else
    {
        error("put font %d:%d\n", font, character);
    }
}
 
 
/* TEXT CACHE */
/* Retrieve a text item from the cache */
DATABLOB *
cache_get_text(RDPCLIENT * This, uint8 cache_id)
{
    DATABLOB *text;
 
    text = &This->cache.textcache[cache_id];
    return text;
}
 
/* Store a text item in the cache */
void
cache_put_text(RDPCLIENT * This, uint8 cache_id, void *data, int length)
{
    DATABLOB *text;
    void * p = malloc(length);
 
    if(p == NULL)
        return;
 
    text = &This->cache.textcache[cache_id];
    if (text->data != NULL)
        free(text->data);
    text->data = p;
    text->size = length;
    memcpy(text->data, data, length);
}
 
 
/* DESKTOP CACHE */
/* Retrieve desktop data from the cache */
uint8 *
cache_get_desktop(RDPCLIENT * This, uint32 offset, int cx, int cy, int bytes_per_pixel)
{
    int length = cx * cy * bytes_per_pixel;
 
    if (offset > sizeof(This->cache.deskcache))
        offset = 0;
 
    if ((offset + length) <= sizeof(This->cache.deskcache))
    {
        return &This->cache.deskcache[offset];
    }
 
    error("get desktop %d:%d\n", offset, length);
    return NULL;
}
 
/* Store desktop data in the cache */
void
cache_put_desktop(RDPCLIENT * This, uint32 offset, int cx, int cy, int scanline, int bytes_per_pixel, uint8 * data)
{
    int length = cx * cy * bytes_per_pixel;
 
    if (offset > sizeof(This->cache.deskcache))
        offset = 0;
 
    if ((offset + length) <= sizeof(This->cache.deskcache))
    {
        cx *= bytes_per_pixel;
        while (cy--)
        {
            memcpy(&This->cache.deskcache[offset], data, cx);
            data += scanline;
            offset += cx;
        }
    }
    else
    {
        error("put desktop %d:%d\n", offset, length);
    }
}
 
 
/* CURSOR CACHE */
/* Retrieve cursor from cache */
HCURSOR
cache_get_cursor(RDPCLIENT * This, uint16 cache_idx)
{
    HCURSOR cursor;
 
    if (cache_idx < NUM_ELEMENTS(This->cache.cursorcache))
    {
        cursor = This->cache.cursorcache[cache_idx];
        if (cursor != NULL)
            return cursor;
    }
 
    error("get cursor %d\n", cache_idx);
    return NULL;
}
 
/* Store cursor in cache */
void
cache_put_cursor(RDPCLIENT * This, uint16 cache_idx, HCURSOR cursor)
{
    HCURSOR old;
 
    if (cache_idx < NUM_ELEMENTS(This->cache.cursorcache))
    {
        old = This->cache.cursorcache[cache_idx];
        if (old != NULL)
            ui_destroy_cursor(This, old);
 
        This->cache.cursorcache[cache_idx] = cursor;
    }
    else
    {
        error("put cursor %d\n", cache_idx);
    }
}