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-rw-r--r--libjpegtwrp/jmem-ashmem.c170
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diff --git a/libjpegtwrp/jmem-ashmem.c b/libjpegtwrp/jmem-ashmem.c
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+++ b/libjpegtwrp/jmem-ashmem.c
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+/*
+ * 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 */
+}