Remove damned ancient DOS line endings from Irrlicht. Hopefully I did not go overboard.

1 files changed, 638 insertions, 638 deletions

diff --git a/libraries/irrlicht-1.8/source/Irrlicht/jpeglib/jmemdos.c b/libraries/irrlicht-1.8/source/Irrlicht/jpeglib/jmemdos.c
index 0955047..60b45c6 100644
--- a/libraries/irrlicht-1.8/source/Irrlicht/jpeglib/jmemdos.c
+++ b/libraries/irrlicht-1.8/source/Irrlicht/jpeglib/jmemdos.c
@@ -1,638 +1,638 @@
-/*

- * jmemdos.c

- *

- * Copyright (C) 1992-1997, Thomas G. Lane.

- * This file is part of the Independent JPEG Group's software.

- * For conditions of distribution and use, see the accompanying README file.

- *

- * This file provides an MS-DOS-compatible implementation of the system-

- * dependent portion of the JPEG memory manager.  Temporary data can be

- * stored in extended or expanded memory as well as in regular DOS files.

- *

- * If you use this file, you must be sure that NEED_FAR_POINTERS is defined

- * if you compile in a small-data memory model; it should NOT be defined if

- * you use a large-data memory model.  This file is not recommended if you

- * are using a flat-memory-space 386 environment such as DJGCC or Watcom C.

- * Also, this code will NOT work if struct fields are aligned on greater than

- * 2-byte boundaries.

- *

- * Based on code contributed by Ge' Weijers.

- */

-

-/*

- * If you have both extended and expanded memory, you may want to change the

- * order in which they are tried in jopen_backing_store.  On a 286 machine

- * expanded memory is usually faster, since extended memory access involves

- * an expensive protected-mode-and-back switch.  On 386 and better, extended

- * memory is usually faster.  As distributed, the code tries extended memory

- * first (what? not everyone has a 386? :-).

- *

- * You can disable use of extended/expanded memory entirely by altering these

- * definitions or overriding them from the Makefile (eg, -DEMS_SUPPORTED=0).

- */

-

-#ifndef XMS_SUPPORTED

-#define XMS_SUPPORTED  1

-#endif

-#ifndef EMS_SUPPORTED

-#define EMS_SUPPORTED  1

-#endif

-

-

-#define JPEG_INTERNALS

-#include "jinclude.h"

-#include "jpeglib.h"

-#include "jmemsys.h"            /* import the system-dependent declarations */

-

-#ifndef HAVE_STDLIB_H           /* <stdlib.h> should declare these */

-extern void * malloc JPP((size_t size));

-extern void free JPP((void *ptr));

-extern char * getenv JPP((const char * name));

-#endif

-

-#ifdef NEED_FAR_POINTERS

-

-#ifdef __TURBOC__

-/* These definitions work for Borland C (Turbo C) */

-#include <alloc.h>              /* need farmalloc(), farfree() */

-#define far_malloc(x)   farmalloc(x)

-#define far_free(x)     farfree(x)

-#else

-/* These definitions work for Microsoft C and compatible compilers */

-#include <malloc.h>             /* need _fmalloc(), _ffree() */

-#define far_malloc(x)   _fmalloc(x)

-#define far_free(x)     _ffree(x)

-#endif

-

-#else /* not NEED_FAR_POINTERS */

-

-#define far_malloc(x)   malloc(x)

-#define far_free(x)     free(x)

-

-#endif /* NEED_FAR_POINTERS */

-

-#ifdef DONT_USE_B_MODE          /* define mode parameters for fopen() */

-#define READ_BINARY     "r"

-#else

-#define READ_BINARY     "rb"

-#endif

-

-#ifndef USE_MSDOS_MEMMGR        /* make sure user got configuration right */

-  You forgot to define USE_MSDOS_MEMMGR in jconfig.h. /* deliberate syntax error */

-#endif

-

-#if MAX_ALLOC_CHUNK >= 65535L   /* make sure jconfig.h got this right */

-  MAX_ALLOC_CHUNK should be less than 64K. /* deliberate syntax error */

-#endif

-

-

-/*

- * Declarations for assembly-language support routines (see jmemdosa.asm).

- *

- * The functions are declared "far" as are all their pointer arguments;

- * this ensures the assembly source code will work regardless of the

- * compiler memory model.  We assume "short" is 16 bits, "long" is 32.

- */

-

-typedef void far * XMSDRIVER;   /* actually a pointer to code */

-typedef struct {                /* registers for calling XMS driver */

-        unsigned short ax, dx, bx;

-        void far * ds_si;

-      } XMScontext;

-typedef struct {                /* registers for calling EMS driver */

-        unsigned short ax, dx, bx;

-        void far * ds_si;

-      } EMScontext;

-

-extern short far jdos_open JPP((short far * handle, char far * filename));

-extern short far jdos_close JPP((short handle));

-extern short far jdos_seek JPP((short handle, long offset));

-extern short far jdos_read JPP((short handle, void far * buffer,

-                                unsigned short count));

-extern short far jdos_write JPP((short handle, void far * buffer,

-                                 unsigned short count));

-extern void far jxms_getdriver JPP((XMSDRIVER far *));

-extern void far jxms_calldriver JPP((XMSDRIVER, XMScontext far *));

-extern short far jems_available JPP((void));

-extern void far jems_calldriver JPP((EMScontext far *));

-

-

-/*

- * Selection of a file name for a temporary file.

- * This is highly system-dependent, and you may want to customize it.

- */

-

-static int next_file_num;       /* to distinguish among several temp files */

-

-LOCAL(void)

-select_file_name (char * fname)

-{

-  const char * env;

-  char * ptr;

-  FILE * tfile;

-

-  /* Keep generating file names till we find one that's not in use */

-  for (;;) {

-    /* Get temp directory name from environment TMP or TEMP variable;

-     * if none, use "."

-     */

-    if ((env = (const char *) getenv("TMP")) == NULL)

-      if ((env = (const char *) getenv("TEMP")) == NULL)

-        env = ".";

-    if (*env == '\0')           /* null string means "." */

-      env = ".";

-    ptr = fname;                /* copy name to fname */

-    while (*env != '\0')

-      *ptr++ = *env++;

-    if (ptr[-1] != '\\' && ptr[-1] != '/')

-      *ptr++ = '\\';            /* append backslash if not in env variable */

-    /* Append a suitable file name */

-    next_file_num++;            /* advance counter */

-    sprintf(ptr, "JPG%03d.TMP", next_file_num);

-    /* Probe to see if file name is already in use */

-    if ((tfile = fopen(fname, READ_BINARY)) == NULL)

-      break;

-    fclose(tfile);              /* oops, it's there; close tfile & try again */

-  }

-}

-

-

-/*

- * Near-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 allocated in far memory, if possible

- */

-

-GLOBAL(void FAR *)

-jpeg_get_large (j_common_ptr cinfo, size_t sizeofobject)

-{

-  return (void FAR *) far_malloc(sizeofobject);

-}

-

-GLOBAL(void)

-jpeg_free_large (j_common_ptr cinfo, void FAR * object, size_t sizeofobject)

-{

-  far_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         300000L /* for total usage about 450K */

-#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.

- */

-

-/*

- * For MS-DOS we support three types of backing storage:

- *   1. Conventional DOS files.  We access these by direct DOS calls rather

- *      than via the stdio package.  This provides a bit better performance,

- *      but the real reason is that the buffers to be read or written are FAR.

- *      The stdio library for small-data memory models can't cope with that.

- *   2. Extended memory, accessed per the XMS V2.0 specification.

- *   3. Expanded memory, accessed per the LIM/EMS 4.0 specification.

- * You'll need copies of those specs to make sense of the related code.

- * The specs are available by Internet FTP from the SIMTEL archives 

- * (oak.oakland.edu and its various mirror sites).  See files

- * pub/msdos/microsoft/xms20.arc and pub/msdos/info/limems41.zip.

- */

-

-

-/*

- * Access methods for a DOS file.

- */

-

-

-METHODDEF(void)

-read_file_store (j_common_ptr cinfo, backing_store_ptr info,

-                 void FAR * buffer_address,

-                 long file_offset, long byte_count)

-{

-  if (jdos_seek(info->handle.file_handle, file_offset))

-    ERREXIT(cinfo, JERR_TFILE_SEEK);

-  /* Since MAX_ALLOC_CHUNK is less than 64K, byte_count will be too. */

-  if (byte_count > 65535L)      /* safety check */

-    ERREXIT(cinfo, JERR_BAD_ALLOC_CHUNK);

-  if (jdos_read(info->handle.file_handle, buffer_address,

-                (unsigned short) byte_count))

-    ERREXIT(cinfo, JERR_TFILE_READ);

-}

-

-

-METHODDEF(void)

-write_file_store (j_common_ptr cinfo, backing_store_ptr info,

-                  void FAR * buffer_address,

-                  long file_offset, long byte_count)

-{

-  if (jdos_seek(info->handle.file_handle, file_offset))

-    ERREXIT(cinfo, JERR_TFILE_SEEK);

-  /* Since MAX_ALLOC_CHUNK is less than 64K, byte_count will be too. */

-  if (byte_count > 65535L)      /* safety check */

-    ERREXIT(cinfo, JERR_BAD_ALLOC_CHUNK);

-  if (jdos_write(info->handle.file_handle, buffer_address,

-                 (unsigned short) byte_count))

-    ERREXIT(cinfo, JERR_TFILE_WRITE);

-}

-

-

-METHODDEF(void)

-close_file_store (j_common_ptr cinfo, backing_store_ptr info)

-{

-  jdos_close(info->handle.file_handle); /* close the file */

-  remove(info->temp_name);      /* delete the file */

-/* If your system doesn't have remove(), try unlink() instead.

- * remove() is the ANSI-standard name for this function, but

- * unlink() was more common in pre-ANSI systems.

- */

-  TRACEMSS(cinfo, 1, JTRC_TFILE_CLOSE, info->temp_name);

-}

-

-

-LOCAL(boolean)

-open_file_store (j_common_ptr cinfo, backing_store_ptr info,

-                 long total_bytes_needed)

-{

-  short handle;

-

-  select_file_name(info->temp_name);

-  if (jdos_open((short far *) & handle, (char far *) info->temp_name)) {

-    /* might as well exit since jpeg_open_backing_store will fail anyway */

-    ERREXITS(cinfo, JERR_TFILE_CREATE, info->temp_name);

-    return FALSE;

-  }

-  info->handle.file_handle = handle;

-  info->read_backing_store = read_file_store;

-  info->write_backing_store = write_file_store;

-  info->close_backing_store = close_file_store;

-  TRACEMSS(cinfo, 1, JTRC_TFILE_OPEN, info->temp_name);

-  return TRUE;                  /* succeeded */

-}

-

-

-/*

- * Access methods for extended memory.

- */

-

-#if XMS_SUPPORTED

-

-static XMSDRIVER xms_driver;    /* saved address of XMS driver */

-

-typedef union {                 /* either long offset or real-mode pointer */

-        long offset;

-        void far * ptr;

-      } XMSPTR;

-

-typedef struct {                /* XMS move specification structure */

-        long length;

-        XMSH src_handle;

-        XMSPTR src;

-        XMSH dst_handle;

-        XMSPTR dst;

-      } XMSspec;

-

-#define ODD(X)  (((X) & 1L) != 0)

-

-

-METHODDEF(void)

-read_xms_store (j_common_ptr cinfo, backing_store_ptr info,

-                void FAR * buffer_address,

-                long file_offset, long byte_count)

-{

-  XMScontext ctx;

-  XMSspec spec;

-  char endbuffer[2];

-

-  /* The XMS driver can't cope with an odd length, so handle the last byte

-   * specially if byte_count is odd.  We don't expect this to be common.

-   */

-

-  spec.length = byte_count & (~ 1L);

-  spec.src_handle = info->handle.xms_handle;

-  spec.src.offset = file_offset;

-  spec.dst_handle = 0;

-  spec.dst.ptr = buffer_address;

-  

-  ctx.ds_si = (void far *) & spec;

-  ctx.ax = 0x0b00;              /* EMB move */

-  jxms_calldriver(xms_driver, (XMScontext far *) & ctx);

-  if (ctx.ax != 1)

-    ERREXIT(cinfo, JERR_XMS_READ);

-

-  if (ODD(byte_count)) {

-    read_xms_store(cinfo, info, (void FAR *) endbuffer,

-                   file_offset + byte_count - 1L, 2L);

-    ((char FAR *) buffer_address)[byte_count - 1L] = endbuffer[0];

-  }

-}

-

-

-METHODDEF(void)

-write_xms_store (j_common_ptr cinfo, backing_store_ptr info,

-                 void FAR * buffer_address,

-                 long file_offset, long byte_count)

-{

-  XMScontext ctx;

-  XMSspec spec;

-  char endbuffer[2];

-

-  /* The XMS driver can't cope with an odd length, so handle the last byte

-   * specially if byte_count is odd.  We don't expect this to be common.

-   */

-

-  spec.length = byte_count & (~ 1L);

-  spec.src_handle = 0;

-  spec.src.ptr = buffer_address;

-  spec.dst_handle = info->handle.xms_handle;

-  spec.dst.offset = file_offset;

-

-  ctx.ds_si = (void far *) & spec;

-  ctx.ax = 0x0b00;              /* EMB move */

-  jxms_calldriver(xms_driver, (XMScontext far *) & ctx);

-  if (ctx.ax != 1)

-    ERREXIT(cinfo, JERR_XMS_WRITE);

-

-  if (ODD(byte_count)) {

-    read_xms_store(cinfo, info, (void FAR *) endbuffer,

-                   file_offset + byte_count - 1L, 2L);

-    endbuffer[0] = ((char FAR *) buffer_address)[byte_count - 1L];

-    write_xms_store(cinfo, info, (void FAR *) endbuffer,

-                    file_offset + byte_count - 1L, 2L);

-  }

-}

-

-

-METHODDEF(void)

-close_xms_store (j_common_ptr cinfo, backing_store_ptr info)

-{

-  XMScontext ctx;

-

-  ctx.dx = info->handle.xms_handle;

-  ctx.ax = 0x0a00;

-  jxms_calldriver(xms_driver, (XMScontext far *) & ctx);

-  TRACEMS1(cinfo, 1, JTRC_XMS_CLOSE, info->handle.xms_handle);

-  /* we ignore any error return from the driver */

-}

-

-

-LOCAL(boolean)

-open_xms_store (j_common_ptr cinfo, backing_store_ptr info,

-                long total_bytes_needed)

-{

-  XMScontext ctx;

-

-  /* Get address of XMS driver */

-  jxms_getdriver((XMSDRIVER far *) & xms_driver);

-  if (xms_driver == NULL)

-    return FALSE;               /* no driver to be had */

-

-  /* Get version number, must be >= 2.00 */

-  ctx.ax = 0x0000;

-  jxms_calldriver(xms_driver, (XMScontext far *) & ctx);

-  if (ctx.ax < (unsigned short) 0x0200)

-    return FALSE;

-

-  /* Try to get space (expressed in kilobytes) */

-  ctx.dx = (unsigned short) ((total_bytes_needed + 1023L) >> 10);

-  ctx.ax = 0x0900;

-  jxms_calldriver(xms_driver, (XMScontext far *) & ctx);

-  if (ctx.ax != 1)

-    return FALSE;

-

-  /* Succeeded, save the handle and away we go */

-  info->handle.xms_handle = ctx.dx;

-  info->read_backing_store = read_xms_store;

-  info->write_backing_store = write_xms_store;

-  info->close_backing_store = close_xms_store;

-  TRACEMS1(cinfo, 1, JTRC_XMS_OPEN, ctx.dx);

-  return TRUE;                  /* succeeded */

-}

-

-#endif /* XMS_SUPPORTED */

-

-

-/*

- * Access methods for expanded memory.

- */

-

-#if EMS_SUPPORTED

-

-/* The EMS move specification structure requires word and long fields aligned

- * at odd byte boundaries.  Some compilers will align struct fields at even

- * byte boundaries.  While it's usually possible to force byte alignment,

- * that causes an overall performance penalty and may pose problems in merging

- * JPEG into a larger application.  Instead we accept some rather dirty code

- * here.  Note this code would fail if the hardware did not allow odd-byte

- * word & long accesses, but all 80x86 CPUs do.

- */

-

-typedef void far * EMSPTR;

-

-typedef union {                 /* EMS move specification structure */

-        long length;            /* It's easy to access first 4 bytes */

-        char bytes[18];         /* Misaligned fields in here! */

-      } EMSspec;

-

-/* Macros for accessing misaligned fields */

-#define FIELD_AT(spec,offset,type)  (*((type *) &(spec.bytes[offset])))

-#define SRC_TYPE(spec)          FIELD_AT(spec,4,char)

-#define SRC_HANDLE(spec)        FIELD_AT(spec,5,EMSH)

-#define SRC_OFFSET(spec)        FIELD_AT(spec,7,unsigned short)

-#define SRC_PAGE(spec)          FIELD_AT(spec,9,unsigned short)

-#define SRC_PTR(spec)           FIELD_AT(spec,7,EMSPTR)

-#define DST_TYPE(spec)          FIELD_AT(spec,11,char)

-#define DST_HANDLE(spec)        FIELD_AT(spec,12,EMSH)

-#define DST_OFFSET(spec)        FIELD_AT(spec,14,unsigned short)

-#define DST_PAGE(spec)          FIELD_AT(spec,16,unsigned short)

-#define DST_PTR(spec)           FIELD_AT(spec,14,EMSPTR)

-

-#define EMSPAGESIZE     16384L  /* gospel, see the EMS specs */

-

-#define HIBYTE(W)  (((W) >> 8) & 0xFF)

-#define LOBYTE(W)  ((W) & 0xFF)

-

-

-METHODDEF(void)

-read_ems_store (j_common_ptr cinfo, backing_store_ptr info,

-                void FAR * buffer_address,

-                long file_offset, long byte_count)

-{

-  EMScontext ctx;

-  EMSspec spec;

-

-  spec.length = byte_count;

-  SRC_TYPE(spec) = 1;

-  SRC_HANDLE(spec) = info->handle.ems_handle;

-  SRC_PAGE(spec)   = (unsigned short) (file_offset / EMSPAGESIZE);

-  SRC_OFFSET(spec) = (unsigned short) (file_offset % EMSPAGESIZE);

-  DST_TYPE(spec) = 0;

-  DST_HANDLE(spec) = 0;

-  DST_PTR(spec)    = buffer_address;

-  

-  ctx.ds_si = (void far *) & spec;

-  ctx.ax = 0x5700;              /* move memory region */

-  jems_calldriver((EMScontext far *) & ctx);

-  if (HIBYTE(ctx.ax) != 0)

-    ERREXIT(cinfo, JERR_EMS_READ);

-}

-

-

-METHODDEF(void)

-write_ems_store (j_common_ptr cinfo, backing_store_ptr info,

-                 void FAR * buffer_address,

-                 long file_offset, long byte_count)

-{

-  EMScontext ctx;

-  EMSspec spec;

-

-  spec.length = byte_count;

-  SRC_TYPE(spec) = 0;

-  SRC_HANDLE(spec) = 0;

-  SRC_PTR(spec)    = buffer_address;

-  DST_TYPE(spec) = 1;

-  DST_HANDLE(spec) = info->handle.ems_handle;

-  DST_PAGE(spec)   = (unsigned short) (file_offset / EMSPAGESIZE);

-  DST_OFFSET(spec) = (unsigned short) (file_offset % EMSPAGESIZE);

-  

-  ctx.ds_si = (void far *) & spec;

-  ctx.ax = 0x5700;              /* move memory region */

-  jems_calldriver((EMScontext far *) & ctx);

-  if (HIBYTE(ctx.ax) != 0)

-    ERREXIT(cinfo, JERR_EMS_WRITE);

-}

-

-

-METHODDEF(void)

-close_ems_store (j_common_ptr cinfo, backing_store_ptr info)

-{

-  EMScontext ctx;

-

-  ctx.ax = 0x4500;

-  ctx.dx = info->handle.ems_handle;

-  jems_calldriver((EMScontext far *) & ctx);

-  TRACEMS1(cinfo, 1, JTRC_EMS_CLOSE, info->handle.ems_handle);

-  /* we ignore any error return from the driver */

-}

-

-

-LOCAL(boolean)

-open_ems_store (j_common_ptr cinfo, backing_store_ptr info,

-                long total_bytes_needed)

-{

-  EMScontext ctx;

-

-  /* Is EMS driver there? */

-  if (! jems_available())

-    return FALSE;

-

-  /* Get status, make sure EMS is OK */

-  ctx.ax = 0x4000;

-  jems_calldriver((EMScontext far *) & ctx);

-  if (HIBYTE(ctx.ax) != 0)

-    return FALSE;

-

-  /* Get version, must be >= 4.0 */

-  ctx.ax = 0x4600;

-  jems_calldriver((EMScontext far *) & ctx);

-  if (HIBYTE(ctx.ax) != 0 || LOBYTE(ctx.ax) < 0x40)

-    return FALSE;

-

-  /* Try to allocate requested space */

-  ctx.ax = 0x4300;

-  ctx.bx = (unsigned short) ((total_bytes_needed + EMSPAGESIZE-1L) / EMSPAGESIZE);

-  jems_calldriver((EMScontext far *) & ctx);

-  if (HIBYTE(ctx.ax) != 0)

-    return FALSE;

-

-  /* Succeeded, save the handle and away we go */

-  info->handle.ems_handle = ctx.dx;

-  info->read_backing_store = read_ems_store;

-  info->write_backing_store = write_ems_store;

-  info->close_backing_store = close_ems_store;

-  TRACEMS1(cinfo, 1, JTRC_EMS_OPEN, ctx.dx);

-  return TRUE;                  /* succeeded */

-}

-

-#endif /* EMS_SUPPORTED */

-

-

-/*

- * Initial opening of a backing-store object.

- */

-

-GLOBAL(void)

-jpeg_open_backing_store (j_common_ptr cinfo, backing_store_ptr info,

-                         long total_bytes_needed)

-{

-  /* Try extended memory, then expanded memory, then regular file. */

-#if XMS_SUPPORTED

-  if (open_xms_store(cinfo, info, total_bytes_needed))

-    return;

-#endif

-#if EMS_SUPPORTED

-  if (open_ems_store(cinfo, info, total_bytes_needed))

-    return;

-#endif

-  if (open_file_store(cinfo, info, total_bytes_needed))

-    return;

-  ERREXITS(cinfo, JERR_TFILE_CREATE, "");

-}

-

-

-/*

- * These routines take care of any system-dependent initialization and

- * cleanup required.

- */

-

-GLOBAL(long)

-jpeg_mem_init (j_common_ptr cinfo)

-{

-  next_file_num = 0;            /* initialize temp file name generator */

-  return DEFAULT_MAX_MEM;       /* default for max_memory_to_use */

-}

-

-GLOBAL(void)

-jpeg_mem_term (j_common_ptr cinfo)

-{

-  /* Microsoft C, at least in v6.00A, will not successfully reclaim freed

-   * blocks of size > 32Kbytes unless we give it a kick in the rear, like so:

-   */

-#ifdef NEED_FHEAPMIN

-  _fheapmin();

-#endif

-}

+/*
+ * jmemdos.c
+ *
+ * Copyright (C) 1992-1997, Thomas G. Lane.
+ * This file is part of the Independent JPEG Group's software.
+ * For conditions of distribution and use, see the accompanying README file.
+ *
+ * This file provides an MS-DOS-compatible implementation of the system-
+ * dependent portion of the JPEG memory manager.  Temporary data can be
+ * stored in extended or expanded memory as well as in regular DOS files.
+ *
+ * If you use this file, you must be sure that NEED_FAR_POINTERS is defined
+ * if you compile in a small-data memory model; it should NOT be defined if
+ * you use a large-data memory model.  This file is not recommended if you
+ * are using a flat-memory-space 386 environment such as DJGCC or Watcom C.
+ * Also, this code will NOT work if struct fields are aligned on greater than
+ * 2-byte boundaries.
+ *
+ * Based on code contributed by Ge' Weijers.
+ */
+
+/*
+ * If you have both extended and expanded memory, you may want to change the
+ * order in which they are tried in jopen_backing_store.  On a 286 machine
+ * expanded memory is usually faster, since extended memory access involves
+ * an expensive protected-mode-and-back switch.  On 386 and better, extended
+ * memory is usually faster.  As distributed, the code tries extended memory
+ * first (what? not everyone has a 386? :-).
+ *
+ * You can disable use of extended/expanded memory entirely by altering these
+ * definitions or overriding them from the Makefile (eg, -DEMS_SUPPORTED=0).
+ */
+
+#ifndef XMS_SUPPORTED
+#define XMS_SUPPORTED  1
+#endif
+#ifndef EMS_SUPPORTED
+#define EMS_SUPPORTED  1
+#endif
+
+
+#define JPEG_INTERNALS
+#include "jinclude.h"
+#include "jpeglib.h"
+#include "jmemsys.h"            /* import the system-dependent declarations */
+
+#ifndef HAVE_STDLIB_H           /* <stdlib.h> should declare these */
+extern void * malloc JPP((size_t size));
+extern void free JPP((void *ptr));
+extern char * getenv JPP((const char * name));
+#endif
+
+#ifdef NEED_FAR_POINTERS
+
+#ifdef __TURBOC__
+/* These definitions work for Borland C (Turbo C) */
+#include <alloc.h>              /* need farmalloc(), farfree() */
+#define far_malloc(x)   farmalloc(x)
+#define far_free(x)     farfree(x)
+#else
+/* These definitions work for Microsoft C and compatible compilers */
+#include <malloc.h>             /* need _fmalloc(), _ffree() */
+#define far_malloc(x)   _fmalloc(x)
+#define far_free(x)     _ffree(x)
+#endif
+
+#else /* not NEED_FAR_POINTERS */
+
+#define far_malloc(x)   malloc(x)
+#define far_free(x)     free(x)
+
+#endif /* NEED_FAR_POINTERS */
+
+#ifdef DONT_USE_B_MODE          /* define mode parameters for fopen() */
+#define READ_BINARY     "r"
+#else
+#define READ_BINARY     "rb"
+#endif
+
+#ifndef USE_MSDOS_MEMMGR        /* make sure user got configuration right */
+  You forgot to define USE_MSDOS_MEMMGR in jconfig.h. /* deliberate syntax error */
+#endif
+
+#if MAX_ALLOC_CHUNK >= 65535L   /* make sure jconfig.h got this right */
+  MAX_ALLOC_CHUNK should be less than 64K. /* deliberate syntax error */
+#endif
+
+
+/*
+ * Declarations for assembly-language support routines (see jmemdosa.asm).
+ *
+ * The functions are declared "far" as are all their pointer arguments;
+ * this ensures the assembly source code will work regardless of the
+ * compiler memory model.  We assume "short" is 16 bits, "long" is 32.
+ */
+
+typedef void far * XMSDRIVER;   /* actually a pointer to code */
+typedef struct {                /* registers for calling XMS driver */
+        unsigned short ax, dx, bx;
+        void far * ds_si;
+      } XMScontext;
+typedef struct {                /* registers for calling EMS driver */
+        unsigned short ax, dx, bx;
+        void far * ds_si;
+      } EMScontext;
+
+extern short far jdos_open JPP((short far * handle, char far * filename));
+extern short far jdos_close JPP((short handle));
+extern short far jdos_seek JPP((short handle, long offset));
+extern short far jdos_read JPP((short handle, void far * buffer,
+                                unsigned short count));
+extern short far jdos_write JPP((short handle, void far * buffer,
+                                 unsigned short count));
+extern void far jxms_getdriver JPP((XMSDRIVER far *));
+extern void far jxms_calldriver JPP((XMSDRIVER, XMScontext far *));
+extern short far jems_available JPP((void));
+extern void far jems_calldriver JPP((EMScontext far *));
+
+
+/*
+ * Selection of a file name for a temporary file.
+ * This is highly system-dependent, and you may want to customize it.
+ */
+
+static int next_file_num;       /* to distinguish among several temp files */
+
+LOCAL(void)
+select_file_name (char * fname)
+{
+  const char * env;
+  char * ptr;
+  FILE * tfile;
+
+  /* Keep generating file names till we find one that's not in use */
+  for (;;) {
+    /* Get temp directory name from environment TMP or TEMP variable;
+     * if none, use "."
+     */
+    if ((env = (const char *) getenv("TMP")) == NULL)
+      if ((env = (const char *) getenv("TEMP")) == NULL)
+        env = ".";
+    if (*env == '\0')           /* null string means "." */
+      env = ".";
+    ptr = fname;                /* copy name to fname */
+    while (*env != '\0')
+      *ptr++ = *env++;
+    if (ptr[-1] != '\\' && ptr[-1] != '/')
+      *ptr++ = '\\';            /* append backslash if not in env variable */
+    /* Append a suitable file name */
+    next_file_num++;            /* advance counter */
+    sprintf(ptr, "JPG%03d.TMP", next_file_num);
+    /* Probe to see if file name is already in use */
+    if ((tfile = fopen(fname, READ_BINARY)) == NULL)
+      break;
+    fclose(tfile);              /* oops, it's there; close tfile & try again */
+  }
+}
+
+
+/*
+ * Near-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 allocated in far memory, if possible
+ */
+
+GLOBAL(void FAR *)
+jpeg_get_large (j_common_ptr cinfo, size_t sizeofobject)
+{
+  return (void FAR *) far_malloc(sizeofobject);
+}
+
+GLOBAL(void)
+jpeg_free_large (j_common_ptr cinfo, void FAR * object, size_t sizeofobject)
+{
+  far_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         300000L /* for total usage about 450K */
+#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.
+ */
+
+/*
+ * For MS-DOS we support three types of backing storage:
+ *   1. Conventional DOS files.  We access these by direct DOS calls rather
+ *      than via the stdio package.  This provides a bit better performance,
+ *      but the real reason is that the buffers to be read or written are FAR.
+ *      The stdio library for small-data memory models can't cope with that.
+ *   2. Extended memory, accessed per the XMS V2.0 specification.
+ *   3. Expanded memory, accessed per the LIM/EMS 4.0 specification.
+ * You'll need copies of those specs to make sense of the related code.
+ * The specs are available by Internet FTP from the SIMTEL archives 
+ * (oak.oakland.edu and its various mirror sites).  See files
+ * pub/msdos/microsoft/xms20.arc and pub/msdos/info/limems41.zip.
+ */
+
+
+/*
+ * Access methods for a DOS file.
+ */
+
+
+METHODDEF(void)
+read_file_store (j_common_ptr cinfo, backing_store_ptr info,
+                 void FAR * buffer_address,
+                 long file_offset, long byte_count)
+{
+  if (jdos_seek(info->handle.file_handle, file_offset))
+    ERREXIT(cinfo, JERR_TFILE_SEEK);
+  /* Since MAX_ALLOC_CHUNK is less than 64K, byte_count will be too. */
+  if (byte_count > 65535L)      /* safety check */
+    ERREXIT(cinfo, JERR_BAD_ALLOC_CHUNK);
+  if (jdos_read(info->handle.file_handle, buffer_address,
+                (unsigned short) byte_count))
+    ERREXIT(cinfo, JERR_TFILE_READ);
+}
+
+
+METHODDEF(void)
+write_file_store (j_common_ptr cinfo, backing_store_ptr info,
+                  void FAR * buffer_address,
+                  long file_offset, long byte_count)
+{
+  if (jdos_seek(info->handle.file_handle, file_offset))
+    ERREXIT(cinfo, JERR_TFILE_SEEK);
+  /* Since MAX_ALLOC_CHUNK is less than 64K, byte_count will be too. */
+  if (byte_count > 65535L)      /* safety check */
+    ERREXIT(cinfo, JERR_BAD_ALLOC_CHUNK);
+  if (jdos_write(info->handle.file_handle, buffer_address,
+                 (unsigned short) byte_count))
+    ERREXIT(cinfo, JERR_TFILE_WRITE);
+}
+
+
+METHODDEF(void)
+close_file_store (j_common_ptr cinfo, backing_store_ptr info)
+{
+  jdos_close(info->handle.file_handle); /* close the file */
+  remove(info->temp_name);      /* delete the file */
+/* If your system doesn't have remove(), try unlink() instead.
+ * remove() is the ANSI-standard name for this function, but
+ * unlink() was more common in pre-ANSI systems.
+ */
+  TRACEMSS(cinfo, 1, JTRC_TFILE_CLOSE, info->temp_name);
+}
+
+
+LOCAL(boolean)
+open_file_store (j_common_ptr cinfo, backing_store_ptr info,
+                 long total_bytes_needed)
+{
+  short handle;
+
+  select_file_name(info->temp_name);
+  if (jdos_open((short far *) & handle, (char far *) info->temp_name)) {
+    /* might as well exit since jpeg_open_backing_store will fail anyway */
+    ERREXITS(cinfo, JERR_TFILE_CREATE, info->temp_name);
+    return FALSE;
+  }
+  info->handle.file_handle = handle;
+  info->read_backing_store = read_file_store;
+  info->write_backing_store = write_file_store;
+  info->close_backing_store = close_file_store;
+  TRACEMSS(cinfo, 1, JTRC_TFILE_OPEN, info->temp_name);
+  return TRUE;                  /* succeeded */
+}
+
+
+/*
+ * Access methods for extended memory.
+ */
+
+#if XMS_SUPPORTED
+
+static XMSDRIVER xms_driver;    /* saved address of XMS driver */
+
+typedef union {                 /* either long offset or real-mode pointer */
+        long offset;
+        void far * ptr;
+      } XMSPTR;
+
+typedef struct {                /* XMS move specification structure */
+        long length;
+        XMSH src_handle;
+        XMSPTR src;
+        XMSH dst_handle;
+        XMSPTR dst;
+      } XMSspec;
+
+#define ODD(X)  (((X) & 1L) != 0)
+
+
+METHODDEF(void)
+read_xms_store (j_common_ptr cinfo, backing_store_ptr info,
+                void FAR * buffer_address,
+                long file_offset, long byte_count)
+{
+  XMScontext ctx;
+  XMSspec spec;
+  char endbuffer[2];
+
+  /* The XMS driver can't cope with an odd length, so handle the last byte
+   * specially if byte_count is odd.  We don't expect this to be common.
+   */
+
+  spec.length = byte_count & (~ 1L);
+  spec.src_handle = info->handle.xms_handle;
+  spec.src.offset = file_offset;
+  spec.dst_handle = 0;
+  spec.dst.ptr = buffer_address;
+  
+  ctx.ds_si = (void far *) & spec;
+  ctx.ax = 0x0b00;              /* EMB move */
+  jxms_calldriver(xms_driver, (XMScontext far *) & ctx);
+  if (ctx.ax != 1)
+    ERREXIT(cinfo, JERR_XMS_READ);
+
+  if (ODD(byte_count)) {
+    read_xms_store(cinfo, info, (void FAR *) endbuffer,
+                   file_offset + byte_count - 1L, 2L);
+    ((char FAR *) buffer_address)[byte_count - 1L] = endbuffer[0];
+  }
+}
+
+
+METHODDEF(void)
+write_xms_store (j_common_ptr cinfo, backing_store_ptr info,
+                 void FAR * buffer_address,
+                 long file_offset, long byte_count)
+{
+  XMScontext ctx;
+  XMSspec spec;
+  char endbuffer[2];
+
+  /* The XMS driver can't cope with an odd length, so handle the last byte
+   * specially if byte_count is odd.  We don't expect this to be common.
+   */
+
+  spec.length = byte_count & (~ 1L);
+  spec.src_handle = 0;
+  spec.src.ptr = buffer_address;
+  spec.dst_handle = info->handle.xms_handle;
+  spec.dst.offset = file_offset;
+
+  ctx.ds_si = (void far *) & spec;
+  ctx.ax = 0x0b00;              /* EMB move */
+  jxms_calldriver(xms_driver, (XMScontext far *) & ctx);
+  if (ctx.ax != 1)
+    ERREXIT(cinfo, JERR_XMS_WRITE);
+
+  if (ODD(byte_count)) {
+    read_xms_store(cinfo, info, (void FAR *) endbuffer,
+                   file_offset + byte_count - 1L, 2L);
+    endbuffer[0] = ((char FAR *) buffer_address)[byte_count - 1L];
+    write_xms_store(cinfo, info, (void FAR *) endbuffer,
+                    file_offset + byte_count - 1L, 2L);
+  }
+}
+
+
+METHODDEF(void)
+close_xms_store (j_common_ptr cinfo, backing_store_ptr info)
+{
+  XMScontext ctx;
+
+  ctx.dx = info->handle.xms_handle;
+  ctx.ax = 0x0a00;
+  jxms_calldriver(xms_driver, (XMScontext far *) & ctx);
+  TRACEMS1(cinfo, 1, JTRC_XMS_CLOSE, info->handle.xms_handle);
+  /* we ignore any error return from the driver */
+}
+
+
+LOCAL(boolean)
+open_xms_store (j_common_ptr cinfo, backing_store_ptr info,
+                long total_bytes_needed)
+{
+  XMScontext ctx;
+
+  /* Get address of XMS driver */
+  jxms_getdriver((XMSDRIVER far *) & xms_driver);
+  if (xms_driver == NULL)
+    return FALSE;               /* no driver to be had */
+
+  /* Get version number, must be >= 2.00 */
+  ctx.ax = 0x0000;
+  jxms_calldriver(xms_driver, (XMScontext far *) & ctx);
+  if (ctx.ax < (unsigned short) 0x0200)
+    return FALSE;
+
+  /* Try to get space (expressed in kilobytes) */
+  ctx.dx = (unsigned short) ((total_bytes_needed + 1023L) >> 10);
+  ctx.ax = 0x0900;
+  jxms_calldriver(xms_driver, (XMScontext far *) & ctx);
+  if (ctx.ax != 1)
+    return FALSE;
+
+  /* Succeeded, save the handle and away we go */
+  info->handle.xms_handle = ctx.dx;
+  info->read_backing_store = read_xms_store;
+  info->write_backing_store = write_xms_store;
+  info->close_backing_store = close_xms_store;
+  TRACEMS1(cinfo, 1, JTRC_XMS_OPEN, ctx.dx);
+  return TRUE;                  /* succeeded */
+}
+
+#endif /* XMS_SUPPORTED */
+
+
+/*
+ * Access methods for expanded memory.
+ */
+
+#if EMS_SUPPORTED
+
+/* The EMS move specification structure requires word and long fields aligned
+ * at odd byte boundaries.  Some compilers will align struct fields at even
+ * byte boundaries.  While it's usually possible to force byte alignment,
+ * that causes an overall performance penalty and may pose problems in merging
+ * JPEG into a larger application.  Instead we accept some rather dirty code
+ * here.  Note this code would fail if the hardware did not allow odd-byte
+ * word & long accesses, but all 80x86 CPUs do.
+ */
+
+typedef void far * EMSPTR;
+
+typedef union {                 /* EMS move specification structure */
+        long length;            /* It's easy to access first 4 bytes */
+        char bytes[18];         /* Misaligned fields in here! */
+      } EMSspec;
+
+/* Macros for accessing misaligned fields */
+#define FIELD_AT(spec,offset,type)  (*((type *) &(spec.bytes[offset])))
+#define SRC_TYPE(spec)          FIELD_AT(spec,4,char)
+#define SRC_HANDLE(spec)        FIELD_AT(spec,5,EMSH)
+#define SRC_OFFSET(spec)        FIELD_AT(spec,7,unsigned short)
+#define SRC_PAGE(spec)          FIELD_AT(spec,9,unsigned short)
+#define SRC_PTR(spec)           FIELD_AT(spec,7,EMSPTR)
+#define DST_TYPE(spec)          FIELD_AT(spec,11,char)
+#define DST_HANDLE(spec)        FIELD_AT(spec,12,EMSH)
+#define DST_OFFSET(spec)        FIELD_AT(spec,14,unsigned short)
+#define DST_PAGE(spec)          FIELD_AT(spec,16,unsigned short)
+#define DST_PTR(spec)           FIELD_AT(spec,14,EMSPTR)
+
+#define EMSPAGESIZE     16384L  /* gospel, see the EMS specs */
+
+#define HIBYTE(W)  (((W) >> 8) & 0xFF)
+#define LOBYTE(W)  ((W) & 0xFF)
+
+
+METHODDEF(void)
+read_ems_store (j_common_ptr cinfo, backing_store_ptr info,
+                void FAR * buffer_address,
+                long file_offset, long byte_count)
+{
+  EMScontext ctx;
+  EMSspec spec;
+
+  spec.length = byte_count;
+  SRC_TYPE(spec) = 1;
+  SRC_HANDLE(spec) = info->handle.ems_handle;
+  SRC_PAGE(spec)   = (unsigned short) (file_offset / EMSPAGESIZE);
+  SRC_OFFSET(spec) = (unsigned short) (file_offset % EMSPAGESIZE);
+  DST_TYPE(spec) = 0;
+  DST_HANDLE(spec) = 0;
+  DST_PTR(spec)    = buffer_address;
+  
+  ctx.ds_si = (void far *) & spec;
+  ctx.ax = 0x5700;              /* move memory region */
+  jems_calldriver((EMScontext far *) & ctx);
+  if (HIBYTE(ctx.ax) != 0)
+    ERREXIT(cinfo, JERR_EMS_READ);
+}
+
+
+METHODDEF(void)
+write_ems_store (j_common_ptr cinfo, backing_store_ptr info,
+                 void FAR * buffer_address,
+                 long file_offset, long byte_count)
+{
+  EMScontext ctx;
+  EMSspec spec;
+
+  spec.length = byte_count;
+  SRC_TYPE(spec) = 0;
+  SRC_HANDLE(spec) = 0;
+  SRC_PTR(spec)    = buffer_address;
+  DST_TYPE(spec) = 1;
+  DST_HANDLE(spec) = info->handle.ems_handle;
+  DST_PAGE(spec)   = (unsigned short) (file_offset / EMSPAGESIZE);
+  DST_OFFSET(spec) = (unsigned short) (file_offset % EMSPAGESIZE);
+  
+  ctx.ds_si = (void far *) & spec;
+  ctx.ax = 0x5700;              /* move memory region */
+  jems_calldriver((EMScontext far *) & ctx);
+  if (HIBYTE(ctx.ax) != 0)
+    ERREXIT(cinfo, JERR_EMS_WRITE);
+}
+
+
+METHODDEF(void)
+close_ems_store (j_common_ptr cinfo, backing_store_ptr info)
+{
+  EMScontext ctx;
+
+  ctx.ax = 0x4500;
+  ctx.dx = info->handle.ems_handle;
+  jems_calldriver((EMScontext far *) & ctx);
+  TRACEMS1(cinfo, 1, JTRC_EMS_CLOSE, info->handle.ems_handle);
+  /* we ignore any error return from the driver */
+}
+
+
+LOCAL(boolean)
+open_ems_store (j_common_ptr cinfo, backing_store_ptr info,
+                long total_bytes_needed)
+{
+  EMScontext ctx;
+
+  /* Is EMS driver there? */
+  if (! jems_available())
+    return FALSE;
+
+  /* Get status, make sure EMS is OK */
+  ctx.ax = 0x4000;
+  jems_calldriver((EMScontext far *) & ctx);
+  if (HIBYTE(ctx.ax) != 0)
+    return FALSE;
+
+  /* Get version, must be >= 4.0 */
+  ctx.ax = 0x4600;
+  jems_calldriver((EMScontext far *) & ctx);
+  if (HIBYTE(ctx.ax) != 0 || LOBYTE(ctx.ax) < 0x40)
+    return FALSE;
+
+  /* Try to allocate requested space */
+  ctx.ax = 0x4300;
+  ctx.bx = (unsigned short) ((total_bytes_needed + EMSPAGESIZE-1L) / EMSPAGESIZE);
+  jems_calldriver((EMScontext far *) & ctx);
+  if (HIBYTE(ctx.ax) != 0)
+    return FALSE;
+
+  /* Succeeded, save the handle and away we go */
+  info->handle.ems_handle = ctx.dx;
+  info->read_backing_store = read_ems_store;
+  info->write_backing_store = write_ems_store;
+  info->close_backing_store = close_ems_store;
+  TRACEMS1(cinfo, 1, JTRC_EMS_OPEN, ctx.dx);
+  return TRUE;                  /* succeeded */
+}
+
+#endif /* EMS_SUPPORTED */
+
+
+/*
+ * Initial opening of a backing-store object.
+ */
+
+GLOBAL(void)
+jpeg_open_backing_store (j_common_ptr cinfo, backing_store_ptr info,
+                         long total_bytes_needed)
+{
+  /* Try extended memory, then expanded memory, then regular file. */
+#if XMS_SUPPORTED
+  if (open_xms_store(cinfo, info, total_bytes_needed))
+    return;
+#endif
+#if EMS_SUPPORTED
+  if (open_ems_store(cinfo, info, total_bytes_needed))
+    return;
+#endif
+  if (open_file_store(cinfo, info, total_bytes_needed))
+    return;
+  ERREXITS(cinfo, JERR_TFILE_CREATE, "");
+}
+
+
+/*
+ * These routines take care of any system-dependent initialization and
+ * cleanup required.
+ */
+
+GLOBAL(long)
+jpeg_mem_init (j_common_ptr cinfo)
+{
+  next_file_num = 0;            /* initialize temp file name generator */
+  return DEFAULT_MAX_MEM;       /* default for max_memory_to_use */
+}
+
+GLOBAL(void)
+jpeg_mem_term (j_common_ptr cinfo)
+{
+  /* Microsoft C, at least in v6.00A, will not successfully reclaim freed
+   * blocks of size > 32Kbytes unless we give it a kick in the rear, like so:
+   */
+#ifdef NEED_FHEAPMIN
+  _fheapmin();
+#endif
+}