gimp/app/temp_buf.c

556 lines
12 KiB
C

/* The GIMP -- an image manipulation program
* Copyright (C) 1995 Spencer Kimball and Peter Mattis
*
* 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., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#include <errno.h>
#include <stdlib.h>
#include <stdio.h>
#include <unistd.h>
#include <string.h>
#include <sys/stat.h>
#include "appenv.h"
#include "drawable.h"
#include "errors.h"
#include "gdisplay.h"
#include "general.h"
#include "gimprc.h"
#include "paint_funcs.h"
#include "temp_buf.h"
static unsigned char * temp_buf_allocate (unsigned int);
static void temp_buf_to_color (TempBuf *, TempBuf *);
static void temp_buf_to_gray (TempBuf *, TempBuf *);
/* Memory management */
static unsigned char *
temp_buf_allocate (size)
unsigned int size;
{
unsigned char * data;
data = (unsigned char *) g_malloc (size);
return data;
}
/* The conversion routines */
static void
temp_buf_to_color (src_buf, dest_buf)
TempBuf * src_buf;
TempBuf * dest_buf;
{
unsigned char *src;
unsigned char *dest;
long num_bytes;
src = temp_buf_data (src_buf);
dest = temp_buf_data (dest_buf);
num_bytes = src_buf->width * src_buf->height;
while (num_bytes--)
{
*dest++ = *src++; /* alpha channel */
*dest++ = *src;
*dest++ = *src;
*dest++ = *src++;
}
}
static void
temp_buf_to_gray (src_buf, dest_buf)
TempBuf * src_buf;
TempBuf * dest_buf;
{
unsigned char *src;
unsigned char *dest;
long num_bytes;
float pix;
src = temp_buf_data (src_buf);
dest = temp_buf_data (dest_buf);
num_bytes = src_buf->width * src_buf->height;
while (num_bytes--)
{
*dest++ = *src++; /* alpha channel */
pix = 0.001;
pix += 0.30 * *src++;
pix += 0.59 * *src++;
pix += 0.11 * *src++;
*dest++ = (unsigned char) pix;
}
}
TempBuf *
temp_buf_new (width, height, bytes, x, y, col)
int width;
int height;
int bytes;
int x, y;
unsigned char * col;
{
long i;
int j;
unsigned char * init, * data;
TempBuf * temp;
temp = (TempBuf *) g_malloc (sizeof (TempBuf));
temp->width = width;
temp->height = height;
temp->bytes = bytes;
temp->x = x;
temp->y = y;
temp->swapped = FALSE;
temp->filename = NULL;
temp->data = temp_buf_allocate (width * height * bytes);
/* initialize the data */
if (col)
{
i = width * height;
data = temp->data;
while (i--)
{
j = bytes;
init = col;
while (j--)
*data++ = *init++;
}
}
return temp;
}
TempBuf *
temp_buf_copy (src, dest)
TempBuf * src;
TempBuf * dest;
{
TempBuf * new;
long length;
if (!src)
{
warning ("trying to copy a temp buf which is NULL.");
return dest;
}
if (!dest)
new = temp_buf_new (src->width, src->height, src->bytes, 0, 0, NULL);
else
{
new = dest;
if (dest->width != src->width || dest->height != src->height)
warning ("In temp_buf_copy, the widths or heights don't match.");
}
/* The temp buf is smart, and can translate between color and gray */
if (src->bytes != new->bytes)
{
if (src->bytes == 4) /* RGB color */
temp_buf_to_gray (src, new);
else if (src->bytes == 2) /* grayscale */
temp_buf_to_color (src, new);
else
warning ("Cannot convert from indexed color.");
}
else
{
/* make the copy */
length = src->width * src->height * src->bytes;
memcpy (temp_buf_data (new), temp_buf_data (src), length);
}
return new;
}
TempBuf *
temp_buf_resize (buf, bytes, x, y, w, h)
TempBuf * buf;
int bytes;
int x, y;
int w, h;
{
int size;
/* calculate the requested size */
size = w * h * bytes;
/* First, configure the canvas buffer */
if (!buf)
buf = temp_buf_new (w, h, bytes, x, y, NULL);
else
{
if (size != (buf->width * buf->height * buf->bytes))
{
/* Make sure the temp buf is unswapped */
temp_buf_unswap (buf);
/* Reallocate the data for it */
buf->data = g_realloc (buf->data, size);
}
/* Make sure the temp buf fields are valid */
buf->x = x;
buf->y = y;
buf->width = w;
buf->height = h;
buf->bytes = bytes;
}
return buf;
}
TempBuf *
temp_buf_copy_area (src, dest, x, y, w, h, border)
TempBuf * src;
TempBuf * dest;
int x, y;
int w, h;
int border;
{
TempBuf * new;
PixelRegion srcR, destR;
unsigned char empty[MAX_CHANNELS] = { 0, 0, 0, 0 };
int x1, y1, x2, y2;
if (!src)
{
warning ("trying to copy a temp buf which is NULL.");
return dest;
}
/* some bounds checking */
x1 = BOUNDS (x, 0, src->width);
y1 = BOUNDS (y, 0, src->height);
x2 = BOUNDS (x + w, 0, src->width);
y2 = BOUNDS (y + h, 0, src->height);
if (!(x2 - x1) || !(y2 - y1))
return dest;
x = x1 - border;
y = y1 - border;
w = (x2 - x1) + border * 2;
h = (y2 - y1) + border * 2;
if (!dest)
new = temp_buf_new (w, h, src->bytes, x, y, empty);
else
{
new = dest;
if (dest->bytes != src->bytes)
warning ("In temp_buf_copy_area, the widths or heights or bytes don't match.");
}
/* Set the offsets for the dest */
new->x = src->x + x;
new->y = src->y + y;
/* Copy the region */
srcR.bytes = src->bytes;
srcR.w = (x2 - x1);
srcR.h = (y2 - y1);
srcR.rowstride = src->bytes * src->width;
srcR.data = temp_buf_data (src) + y1 * srcR.rowstride + x1 * srcR.bytes;
destR.rowstride = new->bytes * new->width;
destR.data = temp_buf_data (new) + (y1 - y) * destR.rowstride + (x1 - x) * srcR.bytes;
copy_region (&srcR, &destR);
return new;
}
void
temp_buf_free (temp_buf)
TempBuf * temp_buf;
{
if (temp_buf->data)
g_free (temp_buf->data);
if (temp_buf->swapped)
temp_buf_swap_free (temp_buf);
g_free (temp_buf);
}
unsigned char *
temp_buf_data (temp_buf)
TempBuf * temp_buf;
{
if (temp_buf->swapped)
temp_buf_unswap (temp_buf);
return temp_buf->data;
}
/******************************************************************
* Mask buffer functions *
******************************************************************/
MaskBuf *
mask_buf_new (width, height)
int width;
int height;
{
static unsigned char empty = 0;
return (temp_buf_new (width, height, 1, 0, 0, &empty));
}
void
mask_buf_free (mask)
MaskBuf * mask;
{
temp_buf_free ((TempBuf *) mask);
}
unsigned char *
mask_buf_data (mask_buf)
MaskBuf * mask_buf;
{
if (mask_buf->swapped)
temp_buf_unswap (mask_buf);
return mask_buf->data;
}
/******************************************************************
* temp buffer disk caching functions *
******************************************************************/
/* NOTES:
* Disk caching is setup as follows:
* On a call to temp_buf_swap, the TempBuf parameter is stored
* in a temporary variable called cached_in_memory.
* On the next call to temp_buf_swap, if cached_in_memory is non-null,
* cached_in_memory is moved to disk, and the latest TempBuf parameter
* is stored in cached_in_memory. This method keeps the latest TempBuf
* structure in memory instead of moving it directly to disk as requested.
* On a call to temp_buf_unswap, if cached_in_memory is non-null, it is
* compared against the requested TempBuf. If they are the same, nothing
* must be moved in from disk since it still resides in memory. However,
* if the two pointers are different, the requested TempBuf is retrieved
* from disk. In the former case, cached_in_memory is set to NULL;
* in the latter case, cached_in_memory is left unchanged.
* If temp_buf_swap_free is called, cached_in_memory must be checked
* against the temp buf being freed. If they are the same, then cached_in_memory
* must be set to NULL;
*
* In the case where memory usage is set to "stingy":
* temp bufs are not cached in memory at all, they go right to disk.
*/
#define MAX_FILENAME 2048
/* a static counter for generating unique filenames */
static int swap_index = 0;
static char filename_buf[MAX_FILENAME];
/* a static pointer which keeps track of the last request for a swapped buffer */
static TempBuf * cached_in_memory = NULL;
static char *
generate_unique_filename (void)
{
pid_t pid;
pid = getpid ();
sprintf (filename_buf, "%s/gimp%d.%d", temp_path, (int) pid, swap_index++);
return g_strdup (filename_buf);
}
void
temp_buf_swap (buf)
TempBuf * buf;
{
TempBuf * swap;
char * filename;
struct stat stat_buf;
int err;
FILE * fp;
if (!buf || buf->swapped)
return;
/* Set the swapped flag */
buf->swapped = TRUE;
if (stingy_memory_use)
swap = buf;
else
{
swap = cached_in_memory;
cached_in_memory = buf;
}
/* For the case where there is no temp buf ready to be moved to disk, return */
if (!swap)
return;
/* Get a unique filename for caching the data to a UNIX file */
filename = generate_unique_filename ();
/* Check if generated filename is valid */
err = stat (filename, &stat_buf);
if (!err)
{
if (stat_buf.st_mode & S_IFDIR)
{
warning ("Error in temp buf caching: \"%s\" is a directory (cannot overwrite)",
filename);
g_free (filename);
return;
}
}
/* Open file for overwrite */
if ((fp = fopen (filename, "w")))
{
fwrite (swap->data, swap->width * swap->height * swap->bytes, 1, fp);
fclose (fp);
}
else
{
perror ("Error in temp buf caching");
warning ("Cannot write \"%s\"", filename);
g_free (filename);
return;
}
/* Finally, free the buffer's data */
g_free (swap->data);
swap->data = NULL;
swap->filename = filename;
}
void
temp_buf_unswap (buf)
TempBuf * buf;
{
struct stat stat_buf;
FILE * fp;
if (!buf || !buf->swapped)
return;
/* Set the swapped flag */
buf->swapped = FALSE;
/* If the requested temp buf is still in memory, simply return */
if (cached_in_memory == buf)
{
cached_in_memory = NULL;
return;
}
/* Allocate memory for the buffer's data */
buf->data = temp_buf_allocate (buf->width * buf->height * buf->bytes);
/* Find out if the filename of the swapped data is an existing file... */
if (!stat (buf->filename, &stat_buf))
{
if ((fp = fopen (buf->filename, "r")))
{
fread (buf->data, buf->width * buf->height * buf->bytes, 1, fp);
fclose (fp);
}
else
perror ("Error in temp buf caching");
/* Delete the swap file */
unlink (buf->filename);
}
else
warning ("Error in temp buf caching: information swapped to disk was lost!");
if (buf->filename)
g_free (buf->filename); /* free filename */
buf->filename = NULL;
}
void
temp_buf_swap_free (buf)
TempBuf * buf;
{
struct stat stat_buf;
if (!buf->swapped)
return;
/* Set the swapped flag */
buf->swapped = FALSE;
/* If the requested temp buf is cached in memory... */
if (cached_in_memory == buf)
{
cached_in_memory = NULL;
return;
}
/* Find out if the filename of the swapped data is an existing file... */
if (!stat (buf->filename, &stat_buf))
{
/* Delete the swap file */
unlink (buf->filename);
}
else
warning ("Error in temp buf disk swapping: information swapped to disk was lost!");
if (buf->filename)
g_free (buf->filename); /* free filename */
buf->filename = NULL;
}
void
swapping_free (void)
{
if (cached_in_memory)
temp_buf_free (cached_in_memory);
}