1 /* 2 * jmemnobs.c 3 * 4 * Copyright (C) 1992-1996, Thomas G. Lane. 5 * This file is part of the Independent JPEG Group's software. 6 * For conditions of distribution and use, see the accompanying README file. 7 * 8 * This file provides a really simple implementation of the system- 9 * dependent portion of the JPEG memory manager. This implementation 10 * assumes that no backing-store files are needed: all required space 11 * can be obtained from malloc(). 12 * This is very portable in the sense that it'll compile on almost anything, 13 * but you'd better have lots of main memory (or virtual memory) if you want 14 * to process big images. 15 * Note that the max_memory_to_use option is ignored by this implementation. 16 */ 17 18 #define JPEG_INTERNALS 19 #include "jinclude.h" 20 #include "jpeglib.h" 21 #include "jmemsys.h" /* import the system-dependent declarations */ 22 23 #ifndef HAVE_STDLIB_H /* <stdlib.h> should declare malloc(),free() */ 24 extern void * malloc JPP((size_t size)); 25 extern void free JPP((void *ptr)); 26 #endif 27 28 29 /* 30 * Memory allocation and freeing are controlled by the regular library 31 * routines malloc() and free(). 32 */ 33 34 GLOBAL(void *) 35 jpeg_get_small (j_common_ptr cinfo, size_t sizeofobject) 36 { 37 return (void *) malloc(sizeofobject); 38 } 39 40 GLOBAL(void) 41 jpeg_free_small (j_common_ptr cinfo, void * object, size_t sizeofobject) 42 { 43 free(object); 44 } 45 46 47 /* 48 * "Large" objects are treated the same as "small" ones. 49 * NB: although we include FAR keywords in the routine declarations, 50 * this file won't actually work in 80x86 small/medium model; at least, 51 * you probably won't be able to process useful-size images in only 64KB. 52 */ 53 54 GLOBAL(void FAR *) 55 jpeg_get_large (j_common_ptr cinfo, size_t sizeofobject) 56 { 57 return (void FAR *) malloc(sizeofobject); 58 } 59 60 GLOBAL(void) 61 jpeg_free_large (j_common_ptr cinfo, void FAR * object, size_t sizeofobject) 62 { 63 free(object); 64 } 65 66 67 /* 68 * This routine computes the total memory space available for allocation. 69 * Here we always say, "we got all you want bud!" 70 */ 71 72 GLOBAL(long) 73 jpeg_mem_available (j_common_ptr cinfo, long min_bytes_needed, 74 long max_bytes_needed, long already_allocated) 75 { 76 return max_bytes_needed; 77 } 78 79 80 /* 81 * Backing store (temporary file) management. 82 * Since jpeg_mem_available always promised the moon, 83 * this should never be called and we can just error out. 84 */ 85 86 GLOBAL(void) 87 jpeg_open_backing_store (j_common_ptr cinfo, backing_store_ptr info, 88 long total_bytes_needed) 89 { 90 ERREXIT(cinfo, JERR_NO_BACKING_STORE); 91 } 92 93 94 /* 95 * These routines take care of any system-dependent initialization and 96 * cleanup required. Here, there isn't any. 97 */ 98 99 GLOBAL(long) 100 jpeg_mem_init (j_common_ptr cinfo) 101 { 102 return 0; /* just set max_memory_to_use to 0 */ 103 } 104 105 GLOBAL(void) 106 jpeg_mem_term (j_common_ptr cinfo) 107 { 108 /* no work */ 109 } 110