1 /* 2 * Copyright (C) 2007-2008 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 #define JPEG_INTERNALS 18 #include "jinclude.h" 19 #include "jpeglib.h" 20 #include "jmemsys.h" /* import the system-dependent declarations */ 21 22 #include <cutils/ashmem.h> 23 #include <unistd.h> 24 #include <sys/mman.h> 25 26 #ifndef HAVE_STDLIB_H /* <stdlib.h> should declare malloc(),free() */ 27 extern void * malloc JPP((size_t size)); 28 extern void free JPP((void *ptr)); 29 #endif 30 31 /* 32 * Memory allocation and freeing are controlled by the regular library 33 * routines malloc() and free(). 34 */ 35 36 GLOBAL(void *) 37 jpeg_get_small (j_common_ptr cinfo, size_t sizeofobject) 38 { 39 return (void *) malloc(sizeofobject); 40 } 41 42 GLOBAL(void) 43 jpeg_free_small (j_common_ptr cinfo, void * object, size_t sizeofobject) 44 { 45 free(object); 46 } 47 48 49 /* 50 * "Large" objects are treated the same as "small" ones. 51 * NB: although we include FAR keywords in the routine declarations, 52 * this file won't actually work in 80x86 small/medium model; at least, 53 * you probably won't be able to process useful-size images in only 64KB. 54 */ 55 56 GLOBAL(void FAR *) 57 jpeg_get_large (j_common_ptr cinfo, size_t sizeofobject) 58 { 59 return (void FAR *) malloc(sizeofobject); 60 } 61 62 GLOBAL(void) 63 jpeg_free_large (j_common_ptr cinfo, void FAR * object, size_t sizeofobject) 64 { 65 free(object); 66 } 67 68 /* 69 * This routine computes the total memory space available for allocation. 70 * It's impossible to do this in a portable way; our current solution is 71 * to make the user tell us (with a default value set at compile time). 72 * If you can actually get the available space, it's a good idea to subtract 73 * a slop factor of 5% or so. 74 */ 75 76 #ifndef DEFAULT_MAX_MEM /* so can override from makefile */ 77 #define DEFAULT_MAX_MEM 10000000L /* default: ten megabyte */ 78 #endif 79 80 GLOBAL(long) 81 jpeg_mem_available (j_common_ptr cinfo, long min_bytes_needed, 82 long max_bytes_needed, long already_allocated) 83 { 84 return cinfo->mem->max_memory_to_use - already_allocated; 85 } 86 87 88 /* 89 * Backing store (temporary file) management. 90 * Backing store objects are only used when the value returned by 91 * jpeg_mem_available is less than the total space needed. You can dispense 92 * with these routines if you have plenty of virtual memory; see jmemnobs.c. 93 */ 94 95 METHODDEF(void) 96 read_backing_store (j_common_ptr cinfo, backing_store_ptr info, 97 void FAR * buffer_address, 98 long file_offset, long byte_count) 99 { 100 memmove(buffer_address, info->addr + file_offset, byte_count); 101 } 102 103 104 METHODDEF(void) 105 write_backing_store (j_common_ptr cinfo, backing_store_ptr info, 106 void FAR * buffer_address, 107 long file_offset, long byte_count) 108 { 109 memmove(info->addr + file_offset, buffer_address, byte_count); 110 } 111 112 113 METHODDEF(void) 114 close_backing_store (j_common_ptr cinfo, backing_store_ptr info) 115 { 116 munmap(info->addr, info->size); 117 close(info->temp_file); 118 } 119 120 LOCAL(int) 121 get_ashmem(backing_store_ptr info, long total_bytes_needed) 122 { 123 char path[1024]; 124 snprintf(path, 1023, "%d.tmp.ashmem", getpid()); 125 int fd = ashmem_create_region(path, total_bytes_needed); 126 if (fd == -1) { 127 return -1; 128 } 129 int err = ashmem_set_prot_region(fd, PROT_READ | PROT_WRITE); 130 if (err) { 131 return -1; 132 } 133 info->addr = mmap(NULL, total_bytes_needed, PROT_READ | PROT_WRITE, MAP_PRIVATE, fd, 0); 134 info->size = total_bytes_needed; 135 info->temp_file = fd; 136 return fd; 137 } 138 139 /* 140 * Initial opening of a backing-store object. 141 * This version uses ashmem to get a shared memory of total-bytes_needed. 142 */ 143 144 GLOBAL(void) 145 jpeg_open_backing_store (j_common_ptr cinfo, backing_store_ptr info, 146 long total_bytes_needed) 147 { 148 if (get_ashmem(info, total_bytes_needed) == -1) 149 ERREXITS(cinfo, JERR_TFILE_CREATE, ""); 150 info->read_backing_store = read_backing_store; 151 info->write_backing_store = write_backing_store; 152 info->close_backing_store = close_backing_store; 153 } 154 155 /* 156 * These routines take care of any system-dependent initialization and 157 * cleanup required. 158 */ 159 160 GLOBAL(long) 161 jpeg_mem_init (j_common_ptr cinfo) 162 { 163 return DEFAULT_MAX_MEM; /* default for max_memory_to_use */ 164 } 165 166 GLOBAL(void) 167 jpeg_mem_term (j_common_ptr cinfo) 168 { 169 /* no work */ 170 } 171