jmemnobs.cpp 2.6 KB

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  1. /*
  2. * jmemnobs.c
  3. *
  4. * Copyright (C) 1992-1994, 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 ri.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. #define JPEG_INTERNALS
  18. #include "jinclude.h"
  19. #include "jpeglib.h"
  20. #include "jmemsys.h" /* import the system-dependent declarations */
  21. /*
  22. * Memory allocation and ri.Freeing are controlled by the regular library
  23. * routines ri.Malloc() and ri.Free().
  24. */
  25. GLOBAL void *
  26. jpeg_get_small (j_common_ptr cinfo, size_t sizeofobject)
  27. {
  28. return (void *) malloc(sizeofobject);
  29. }
  30. GLOBAL void
  31. jpeg_free_small (j_common_ptr cinfo, void * object, size_t sizeofobject)
  32. {
  33. free(object);
  34. }
  35. /*
  36. * "Large" objects are treated the same as "small" ones.
  37. * NB: although we include FAR keywords in the routine declarations,
  38. * this file won't actually work in 80x86 small/medium model; at least,
  39. * you probably won't be able to process useful-size images in only 64KB.
  40. */
  41. GLOBAL void FAR *
  42. jpeg_get_large (j_common_ptr cinfo, size_t sizeofobject)
  43. {
  44. return (void FAR *) malloc(sizeofobject);
  45. }
  46. GLOBAL void
  47. jpeg_free_large (j_common_ptr cinfo, void FAR * object, size_t sizeofobject)
  48. {
  49. free(object);
  50. }
  51. /*
  52. * This routine computes the total memory space available for allocation.
  53. * Here we always say, "we got all you want bud!"
  54. */
  55. GLOBAL long
  56. jpeg_mem_available (j_common_ptr cinfo, long min_bytes_needed,
  57. long max_bytes_needed, long already_allocated)
  58. {
  59. return max_bytes_needed;
  60. }
  61. /*
  62. * Backing store (temporary file) management.
  63. * Since jpeg_mem_available always promised the moon,
  64. * this should never be called and we can just error out.
  65. */
  66. GLOBAL void
  67. jpeg_open_backing_store (j_common_ptr cinfo, backing_store_ptr info,
  68. long total_bytes_needed)
  69. {
  70. ERREXIT(cinfo, JERR_NO_BACKING_STORE);
  71. }
  72. /*
  73. * These routines take care of any system-dependent initialization and
  74. * cleanup required. Here, there isn't any.
  75. */
  76. GLOBAL long
  77. jpeg_mem_init (j_common_ptr cinfo)
  78. {
  79. return 0; /* just set max_memory_to_use to 0 */
  80. }
  81. GLOBAL void
  82. jpeg_mem_term (j_common_ptr cinfo)
  83. {
  84. /* no work */
  85. }