source: trunk/libjpeg/jmemmac.c @ 89

Last change on this file since 89 was 15, checked in by Eugene Romanenko, 16 years ago

needed libs update

File size: 9.6 KB
Line 
1/*
2 * jmemmac.c
3 *
4 * Copyright (C) 1992-1997, 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 * jmemmac.c provides an Apple Macintosh implementation of the system-
9 * dependent portion of the JPEG memory manager.
10 *
11 * If you use jmemmac.c, then you must define USE_MAC_MEMMGR in the
12 * JPEG_INTERNALS part of jconfig.h.
13 *
14 * jmemmac.c uses the Macintosh toolbox routines NewPtr and DisposePtr
15 * instead of malloc and free.  It accurately determines the amount of
16 * memory available by using CompactMem.  Notice that if left to its
17 * own devices, this code can chew up all available space in the
18 * application's zone, with the exception of the rather small "slop"
19 * factor computed in jpeg_mem_available().  The application can ensure
20 * that more space is left over by reducing max_memory_to_use.
21 *
22 * Large images are swapped to disk using temporary files and System 7.0+'s
23 * temporary folder functionality.
24 *
25 * Note that jmemmac.c depends on two features of MacOS that were first
26 * introduced in System 7: FindFolder and the FSSpec-based calls.
27 * If your application uses jmemmac.c and is run under System 6 or earlier,
28 * and the jpeg library decides it needs a temporary file, it will abort,
29 * printing error messages about requiring System 7.  (If no temporary files
30 * are created, it will run fine.)
31 *
32 * If you want to use jmemmac.c in an application that might be used with
33 * System 6 or earlier, then you should remove dependencies on FindFolder
34 * and the FSSpec calls.  You will need to replace FindFolder with some
35 * other mechanism for finding a place to put temporary files, and you
36 * should replace the FSSpec calls with their HFS equivalents:
37 *
38 *     FSpDelete     ->  HDelete
39 *     FSpGetFInfo   ->  HGetFInfo
40 *     FSpCreate     ->  HCreate
41 *     FSpOpenDF     ->  HOpen      *** Note: not HOpenDF ***
42 *     FSMakeFSSpec  ->  (fill in spec by hand.)
43 *
44 * (Use HOpen instead of HOpenDF.  HOpen is just a glue-interface to PBHOpen,
45 * which is on all HFS macs.  HOpenDF is a System 7 addition which avoids the
46 * ages-old problem of names starting with a period.)
47 *
48 * Contributed by Sam Bushell (jsam@iagu.on.net) and
49 * Dan Gildor (gyld@in-touch.com).
50 */
51
52#define JPEG_INTERNALS
53#include "jinclude.h"
54#include "jpeglib.h"
55#include "jmemsys.h"    /* import the system-dependent declarations */
56
57#ifndef USE_MAC_MEMMGR  /* make sure user got configuration right */
58  You forgot to define USE_MAC_MEMMGR in jconfig.h. /* deliberate syntax error */
59#endif
60
61#include <Memory.h>     /* we use the MacOS memory manager */
62#include <Files.h>      /* we use the MacOS File stuff */
63#include <Folders.h>    /* we use the MacOS HFS stuff */
64#include <Script.h>     /* for smSystemScript */
65#include <Gestalt.h>    /* we use Gestalt to test for specific functionality */
66
67#ifndef TEMP_FILE_NAME          /* can override from jconfig.h or Makefile */
68#define TEMP_FILE_NAME  "JPG%03d.TMP"
69#endif
70
71static int next_file_num;       /* to distinguish among several temp files */
72
73
74/*
75 * Memory allocation and freeing are controlled by the MacOS library
76 * routines NewPtr() and DisposePtr(), which allocate fixed-address
77 * storage.  Unfortunately, the IJG library isn't smart enough to cope
78 * with relocatable storage.
79 */
80
81GLOBAL(void *)
82jpeg_get_small (j_common_ptr cinfo, size_t sizeofobject)
83{
84  return (void *) NewPtr(sizeofobject);
85}
86
87GLOBAL(void)
88jpeg_free_small (j_common_ptr cinfo, void * object, size_t sizeofobject)
89{
90  DisposePtr((Ptr) object);
91}
92
93
94/*
95 * "Large" objects are treated the same as "small" ones.
96 * NB: we include FAR keywords in the routine declarations simply for
97 * consistency with the rest of the IJG code; FAR should expand to empty
98 * on rational architectures like the Mac.
99 */
100
101GLOBAL(void FAR *)
102jpeg_get_large (j_common_ptr cinfo, size_t sizeofobject)
103{
104  return (void FAR *) NewPtr(sizeofobject);
105}
106
107GLOBAL(void)
108jpeg_free_large (j_common_ptr cinfo, void FAR * object, size_t sizeofobject)
109{
110  DisposePtr((Ptr) object);
111}
112
113
114/*
115 * This routine computes the total memory space available for allocation.
116 */
117
118GLOBAL(long)
119jpeg_mem_available (j_common_ptr cinfo, long min_bytes_needed,
120                    long max_bytes_needed, long already_allocated)
121{
122  long limit = cinfo->mem->max_memory_to_use - already_allocated;
123  long slop, mem;
124
125  /* Don't ask for more than what application has told us we may use */
126  if (max_bytes_needed > limit && limit > 0)
127    max_bytes_needed = limit;
128  /* Find whether there's a big enough free block in the heap.
129   * CompactMem tries to create a contiguous block of the requested size,
130   * and then returns the size of the largest free block (which could be
131   * much more or much less than we asked for).
132   * We add some slop to ensure we don't use up all available memory.
133   */
134  slop = max_bytes_needed / 16 + 32768L;
135  mem = CompactMem(max_bytes_needed + slop) - slop;
136  if (mem < 0)
137    mem = 0;                    /* sigh, couldn't even get the slop */
138  /* Don't take more than the application says we can have */
139  if (mem > limit && limit > 0)
140    mem = limit;
141  return mem;
142}
143
144
145/*
146 * Backing store (temporary file) management.
147 * Backing store objects are only used when the value returned by
148 * jpeg_mem_available is less than the total space needed.  You can dispense
149 * with these routines if you have plenty of virtual memory; see jmemnobs.c.
150 */
151
152
153METHODDEF(void)
154read_backing_store (j_common_ptr cinfo, backing_store_ptr info,
155                    void FAR * buffer_address,
156                    long file_offset, long byte_count)
157{
158  long bytes = byte_count;
159  long retVal;
160
161  if ( SetFPos ( info->temp_file, fsFromStart, file_offset ) != noErr )
162    ERREXIT(cinfo, JERR_TFILE_SEEK);
163
164  retVal = FSRead ( info->temp_file, &bytes,
165                    (unsigned char *) buffer_address );
166  if ( retVal != noErr || bytes != byte_count )
167    ERREXIT(cinfo, JERR_TFILE_READ);
168}
169
170
171METHODDEF(void)
172write_backing_store (j_common_ptr cinfo, backing_store_ptr info,
173                     void FAR * buffer_address,
174                     long file_offset, long byte_count)
175{
176  long bytes = byte_count;
177  long retVal;
178
179  if ( SetFPos ( info->temp_file, fsFromStart, file_offset ) != noErr )
180    ERREXIT(cinfo, JERR_TFILE_SEEK);
181
182  retVal = FSWrite ( info->temp_file, &bytes,
183                     (unsigned char *) buffer_address );
184  if ( retVal != noErr || bytes != byte_count )
185    ERREXIT(cinfo, JERR_TFILE_WRITE);
186}
187
188
189METHODDEF(void)
190close_backing_store (j_common_ptr cinfo, backing_store_ptr info)
191{
192  FSClose ( info->temp_file );
193  FSpDelete ( &(info->tempSpec) );
194}
195
196
197/*
198 * Initial opening of a backing-store object.
199 *
200 * This version uses FindFolder to find the Temporary Items folder,
201 * and puts the temporary file in there.
202 */
203
204GLOBAL(void)
205jpeg_open_backing_store (j_common_ptr cinfo, backing_store_ptr info,
206                         long total_bytes_needed)
207{
208  short         tmpRef, vRefNum;
209  long          dirID;
210  FInfo         finderInfo;
211  FSSpec        theSpec;
212  Str255        fName;
213  OSErr         osErr;
214  long          gestaltResponse = 0;
215
216  /* Check that FSSpec calls are available. */
217  osErr = Gestalt( gestaltFSAttr, &gestaltResponse );
218  if ( ( osErr != noErr )
219       || !( gestaltResponse & (1<<gestaltHasFSSpecCalls) ) )
220    ERREXITS(cinfo, JERR_TFILE_CREATE, "- System 7.0 or later required");
221  /* TO DO: add a proper error message to jerror.h. */
222
223  /* Check that FindFolder is available. */
224  osErr = Gestalt( gestaltFindFolderAttr, &gestaltResponse );
225  if ( ( osErr != noErr )
226       || !( gestaltResponse & (1<<gestaltFindFolderPresent) ) )
227    ERREXITS(cinfo, JERR_TFILE_CREATE, "- System 7.0 or later required.");
228  /* TO DO: add a proper error message to jerror.h. */
229
230  osErr = FindFolder ( kOnSystemDisk, kTemporaryFolderType, kCreateFolder,
231                       &vRefNum, &dirID );
232  if ( osErr != noErr )
233    ERREXITS(cinfo, JERR_TFILE_CREATE, "- temporary items folder unavailable");
234  /* TO DO: Try putting the temp files somewhere else. */
235
236  /* Keep generating file names till we find one that's not in use */
237  for (;;) {
238    next_file_num++;            /* advance counter */
239
240    sprintf(info->temp_name, TEMP_FILE_NAME, next_file_num);
241    strcpy ( (Ptr)fName+1, info->temp_name );
242    *fName = strlen (info->temp_name);
243    osErr = FSMakeFSSpec ( vRefNum, dirID, fName, &theSpec );
244
245    if ( (osErr = FSpGetFInfo ( &theSpec, &finderInfo ) ) != noErr )
246      break;
247  }
248
249  osErr = FSpCreate ( &theSpec, '????', '????', smSystemScript );
250  if ( osErr != noErr )
251    ERREXITS(cinfo, JERR_TFILE_CREATE, info->temp_name);
252
253  osErr = FSpOpenDF ( &theSpec, fsRdWrPerm, &(info->temp_file) );
254  if ( osErr != noErr )
255    ERREXITS(cinfo, JERR_TFILE_CREATE, info->temp_name);
256
257  info->tempSpec = theSpec;
258
259  info->read_backing_store = read_backing_store;
260  info->write_backing_store = write_backing_store;
261  info->close_backing_store = close_backing_store;
262  TRACEMSS(cinfo, 1, JTRC_TFILE_OPEN, info->temp_name);
263}
264
265
266/*
267 * These routines take care of any system-dependent initialization and
268 * cleanup required.
269 */
270
271GLOBAL(long)
272jpeg_mem_init (j_common_ptr cinfo)
273{
274  next_file_num = 0;
275
276  /* max_memory_to_use will be initialized to FreeMem()'s result;
277   * the calling application might later reduce it, for example
278   * to leave room to invoke multiple JPEG objects.
279   * Note that FreeMem returns the total number of free bytes;
280   * it may not be possible to allocate a single block of this size.
281   */
282  return FreeMem();
283}
284
285GLOBAL(void)
286jpeg_mem_term (j_common_ptr cinfo)
287{
288  /* no work */
289}
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