/*
* Copyright (C) 2007-2008 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#define JPEG_INTERNALS
#include "jinclude.h"
#include "jpeglib.h"
#include "jmemsys.h" /* import the system-dependent declarations */
#include <cutils/ashmem.h>
#include <unistd.h>
#include <sys/mman.h>
#ifndef HAVE_STDLIB_H /* <stdlib.h> should declare malloc(),free() */
extern void * malloc JPP((size_t size));
extern void free JPP((void *ptr));
#endif
/*
* Memory allocation and freeing are controlled by the regular library
* routines malloc() and free().
*/
GLOBAL(void *)
jpeg_get_small (j_common_ptr cinfo, size_t sizeofobject)
{
return (void *) malloc(sizeofobject);
}
GLOBAL(void)
jpeg_free_small (j_common_ptr cinfo, void * object, size_t sizeofobject)
{
free(object);
}
/*
* "Large" objects are treated the same as "small" ones.
* NB: although we include FAR keywords in the routine declarations,
* this file won't actually work in 80x86 small/medium model; at least,
* you probably won't be able to process useful-size images in only 64KB.
*/
GLOBAL(void FAR *)
jpeg_get_large (j_common_ptr cinfo, size_t sizeofobject)
{
return (void FAR *) malloc(sizeofobject);
}
GLOBAL(void)
jpeg_free_large (j_common_ptr cinfo, void FAR * object, size_t sizeofobject)
{
free(object);
}
/*
* This routine computes the total memory space available for allocation.
* It's impossible to do this in a portable way; our current solution is
* to make the user tell us (with a default value set at compile time).
* If you can actually get the available space, it's a good idea to subtract
* a slop factor of 5% or so.
*/
#ifndef DEFAULT_MAX_MEM /* so can override from makefile */
#define DEFAULT_MAX_MEM 10000000L /* default: ten megabyte */
#endif
GLOBAL(long)
jpeg_mem_available (j_common_ptr cinfo, long min_bytes_needed,
long max_bytes_needed, long already_allocated)
{
return cinfo->mem->max_memory_to_use - already_allocated;
}
/*
* Backing store (temporary file) management.
* Backing store objects are only used when the value returned by
* jpeg_mem_available is less than the total space needed. You can dispense
* with these routines if you have plenty of virtual memory; see jmemnobs.c.
*/
METHODDEF(void)
read_backing_store (j_common_ptr cinfo, backing_store_ptr info,
void FAR * buffer_address,
long file_offset, long byte_count)
{
memmove(buffer_address, info->addr + file_offset, byte_count);
}
METHODDEF(void)
write_backing_store (j_common_ptr cinfo, backing_store_ptr info,
void FAR * buffer_address,
long file_offset, long byte_count)
{
memmove(info->addr + file_offset, buffer_address, byte_count);
}
METHODDEF(void)
close_backing_store (j_common_ptr cinfo, backing_store_ptr info)
{
munmap(info->addr, info->size);
close(info->temp_file);
}
LOCAL(int)
get_ashmem(backing_store_ptr info, long total_bytes_needed)
{
char path[1024];
snprintf(path, 1023, "%d.tmp.ashmem", getpid());
int fd = ashmem_create_region(path, total_bytes_needed);
if (fd == -1) {
return -1;
}
int err = ashmem_set_prot_region(fd, PROT_READ | PROT_WRITE);
if (err) {
return -1;
}
info->addr = mmap(NULL, total_bytes_needed, PROT_READ | PROT_WRITE, MAP_PRIVATE, fd, 0);
info->size = total_bytes_needed;
info->temp_file = fd;
return fd;
}
/*
* Initial opening of a backing-store object.
* This version uses ashmem to get a shared memory of total-bytes_needed.
*/
GLOBAL(void)
jpeg_open_backing_store (j_common_ptr cinfo, backing_store_ptr info,
long total_bytes_needed)
{
if (get_ashmem(info, total_bytes_needed) == -1)
ERREXITS(cinfo, JERR_TFILE_CREATE, "");
info->read_backing_store = read_backing_store;
info->write_backing_store = write_backing_store;
info->close_backing_store = close_backing_store;
}
/*
* These routines take care of any system-dependent initialization and
* cleanup required.
*/
GLOBAL(long)
jpeg_mem_init (j_common_ptr cinfo)
{
return DEFAULT_MAX_MEM; /* default for max_memory_to_use */
}
GLOBAL(void)
jpeg_mem_term (j_common_ptr cinfo)
{
/* no work */
}
