Enable DJGPP/MS-DOS build of jasper

[SuperIlu]

Changing line https://github.com/jasper-software/jasper/blob/master/src/libjasper/base/jas_malloc.c#L651 from

#elif defined(__unix__) && (!defined(__linux__) && !defined(__APPLE__))

to

#elif defined(__unix__) && (!defined(__linux__) && !defined(__APPLE__)&& !defined(__DJGPP__))

allows Jasper to be cross compiled for MS-DOS using DJGPP

[mdadams]

Could you please specify a condition that could be tested to explicitly detect the DJGPP/MS-DOS environment? Does this environment define something like djgpp and msdos? I very strongly prefer to check for this case directly.

[SuperIlu]

DJGPP defines __DJGPP__ as well as __MSDOS__ (also __MSDOS and MSDOS)

Im using jasper in two of my projects and it cross compiles fine for me besides jas_get_total_mem_size()

full dump of preprocessor variables below (obtained with echo | i586-pc-msdosdjgpp-gcc -dM -E -)

#define __GO32 1
#define __DBL_MIN_EXP__ (-1021)
#define __FLT32X_MAX_EXP__ 1024
#define __UINT_LEAST16_MAX__ 0xffff
#define __ATOMIC_ACQUIRE 2
#define __FLT128_MAX_10_EXP__ 4932
#define __FLT_MIN__ 1.17549435082228750796873653722224568e-38F
#define __GCC_IEC_559_COMPLEX 2
#define __UINT_LEAST8_TYPE__ unsigned char
#define __SIZEOF_FLOAT80__ 12
#define __INTMAX_C(c) c ## LL
#define __CHAR_BIT__ 8
#define __UINT8_MAX__ 0xff
#define __i586 1
#define __WINT_MAX__ 0x7fffffff
#define __FLT32_MIN_EXP__ (-125)
#define __ORDER_LITTLE_ENDIAN__ 1234
#define __SIZE_MAX__ 0xffffffffUL
#define __WCHAR_MAX__ 0xffff
#define __GCC_HAVE_SYNC_COMPARE_AND_SWAP_1 1
#define __GCC_HAVE_SYNC_COMPARE_AND_SWAP_2 1
#define __GCC_HAVE_SYNC_COMPARE_AND_SWAP_4 1
#define __DBL_DENORM_MIN__ ((double)4.94065645841246544176568792868221372e-324L)
#define __GCC_HAVE_SYNC_COMPARE_AND_SWAP_8 1
#define __GCC_ATOMIC_CHAR_LOCK_FREE 2
#define __GCC_IEC_559 2
#define __FLT32X_DECIMAL_DIG__ 17
#define __FLT_EVAL_METHOD__ 2
#define __unix__ 1
#define __FLT64_DECIMAL_DIG__ 17
#define __GCC_ATOMIC_CHAR32_T_LOCK_FREE 2
#define __UINT_FAST64_MAX__ 0xffffffffffffffffULL
#define __SIG_ATOMIC_TYPE__ int
#define __DBL_MIN_10_EXP__ (-307)
#define __FINITE_MATH_ONLY__ 0
#define __GNUC_PATCHLEVEL__ 0
#define __FLT32_HAS_DENORM__ 1
#define __UINT_FAST8_MAX__ 0xff
#define __has_include(STR) __has_include__(STR)
#define __DEC64_MAX_EXP__ 385
#define __INT8_C(c) c
#define __INT_LEAST8_WIDTH__ 8
#define __UINT_LEAST64_MAX__ 0xffffffffffffffffULL
#define __SHRT_MAX__ 0x7fff
#define __LDBL_MAX__ 1.18973149535723176502126385303097021e+4932L
#define __FLT64X_MAX_10_EXP__ 4932
#define __UINT_LEAST8_MAX__ 0xff
#define __GCC_ATOMIC_BOOL_LOCK_FREE 2
#define __FLT128_DENORM_MIN__ 6.47517511943802511092443895822764655e-4966F128
#define __UINTMAX_TYPE__ long long unsigned int
#define __DEC32_EPSILON__ 1E-6DF
#define __FLT_EVAL_METHOD_TS_18661_3__ 2
#define __unix 1
#define __UINT32_MAX__ 0xffffffffU
#define __LDBL_MAX_EXP__ 16384
#define __FLT128_MIN_EXP__ (-16381)
#define __WINT_MIN__ (-__WINT_MAX__ - 1)
#define __DJGPP 2
#define __FLT128_MIN_10_EXP__ (-4931)
#define __INT_LEAST16_WIDTH__ 16
#define __SCHAR_MAX__ 0x7f
#define __FLT128_MANT_DIG__ 113
#define __WCHAR_MIN__ 0
#define __INT64_C(c) c ## LL
#define __DBL_DIG__ 15
#define __GCC_ATOMIC_POINTER_LOCK_FREE 2
#define __FLT64X_MANT_DIG__ 64
#define __SIZEOF_INT__ 4
#define __SIZEOF_POINTER__ 4
#define __USER_LABEL_PREFIX__ _
#define __FLT64X_EPSILON__ 1.08420217248550443400745280086994171e-19F64x
#define __STDC_HOSTED__ 1
#define __LDBL_HAS_INFINITY__ 1
#define __MSDOS__ 1
#define __FLT32_DIG__ 6
#define __FLT_EPSILON__ 1.19209289550781250000000000000000000e-7F
#define __SHRT_WIDTH__ 16
#define __LDBL_MIN__ 3.36210314311209350626267781732175260e-4932L
#define __STDC_UTF_16__ 1
#define __DEC32_MAX__ 9.999999E96DF
#define __FLT64X_DENORM_MIN__ 3.64519953188247460252840593361941982e-4951F64x
#define __DJGPP__ 2
#define __FLT32X_HAS_INFINITY__ 1
#define __INT32_MAX__ 0x7fffffff
#define __INT_WIDTH__ 32
#define __SIZEOF_LONG__ 4
#define __UINT16_C(c) c
#define __PTRDIFF_WIDTH__ 32
#define __DECIMAL_DIG__ 21
#define __FLT64_EPSILON__ 2.22044604925031308084726333618164062e-16F64
#define __INTMAX_WIDTH__ 64
#define __has_include_next(STR) __has_include_next__(STR)
#define __FLT64X_MIN_10_EXP__ (-4931)
#define __LDBL_HAS_QUIET_NAN__ 1
#define __FLT64_MANT_DIG__ 53
#define __GNUC__ 7
#define __FLT_HAS_DENORM__ 1
#define __SIZEOF_LONG_DOUBLE__ 12
#define __tune_i586__ 1
#define __BIGGEST_ALIGNMENT__ 16
#define __FLT64_MAX_10_EXP__ 308
#define __DBL_MAX__ ((double)1.79769313486231570814527423731704357e+308L)
#define __INT_FAST32_MAX__ 0x7fffffff
#define __DBL_HAS_INFINITY__ 1
#define __DEC32_MIN_EXP__ (-94)
#define __INTPTR_WIDTH__ 32
#define __FLT32X_HAS_DENORM__ 1
#define __INT_FAST16_TYPE__ short int
#define __LDBL_HAS_DENORM__ 1
#define __FLT128_HAS_INFINITY__ 1
#define __DEC128_MAX__ 9.999999999999999999999999999999999E6144DL
#define __INT_LEAST32_MAX__ 0x7fffffff
#define __DEC32_MIN__ 1E-95DF
#define __pentium 1
#define __DBL_MAX_EXP__ 1024
#define __WCHAR_WIDTH__ 16
#define __FLT32_MAX__ 3.40282346638528859811704183484516925e+38F32
#define __DEC128_EPSILON__ 1E-33DL
#define __ATOMIC_HLE_RELEASE 131072
#define __PTRDIFF_MAX__ 0x7fffffff
#define __ATOMIC_HLE_ACQUIRE 65536
#define __FLT32_HAS_QUIET_NAN__ 1
#define __LONG_LONG_MAX__ 0x7fffffffffffffffLL
#define __SIZEOF_SIZE_T__ 4
#define __FLT64X_MIN_EXP__ (-16381)
#define __SIZEOF_WINT_T__ 4
#define __LONG_LONG_WIDTH__ 64
#define __FLT32_MAX_EXP__ 128
#define __GCC_HAVE_DWARF2_CFI_ASM 1
#define __GXX_ABI_VERSION 1011
#define __FLT_MIN_EXP__ (-125)
#define __GO32__ 1
#define GO32 1
#define __FLT64X_HAS_QUIET_NAN__ 1
#define __INT_FAST64_TYPE__ long long int
#define __FLT64_DENORM_MIN__ 4.94065645841246544176568792868221372e-324F64
#define __DBL_MIN__ ((double)2.22507385850720138309023271733240406e-308L)
#define MSDOS 1
#define __FLT32X_EPSILON__ 2.22044604925031308084726333618164062e-16F32x
#define __FLT64_MIN_EXP__ (-1021)
#define __FLT64_MIN_10_EXP__ (-307)
#define __FLT64X_DECIMAL_DIG__ 21
#define __DEC128_MIN__ 1E-6143DL
#define __REGISTER_PREFIX__
#define __UINT16_MAX__ 0xffff
#define __DBL_HAS_DENORM__ 1
#define __FLT32_MIN__ 1.17549435082228750796873653722224568e-38F32
#define __UINT8_TYPE__ unsigned char
#define __NO_INLINE__ 1
#define __i386 1
#define __FLT_MANT_DIG__ 24
#define __LDBL_DECIMAL_DIG__ 21
#define __i586__ 1
#define __VERSION__ "7.2.0"
#define __UINT64_C(c) c ## ULL
#define __GCC_ATOMIC_INT_LOCK_FREE 2
#define __FLT128_MAX_EXP__ 16384
#define __FLT32_MANT_DIG__ 24
#define __FLOAT_WORD_ORDER__ __ORDER_LITTLE_ENDIAN__
#define __FLT128_HAS_DENORM__ 1
#define __FLT128_DIG__ 33
#define __SCHAR_WIDTH__ 8
#define __INT32_C(c) c
#define __DEC64_EPSILON__ 1E-15DD
#define __ORDER_PDP_ENDIAN__ 3412
#define __DEC128_MIN_EXP__ (-6142)
#define __code_model_32__ 1
#define __FLT32_MAX_10_EXP__ 38
#define __INT_FAST32_TYPE__ int
#define __UINT_LEAST16_TYPE__ short unsigned int
#define __FLT64X_HAS_INFINITY__ 1
#define unix 1
#define __INT16_MAX__ 0x7fff
#define __i386__ 1
#define __SIZE_TYPE__ long unsigned int
#define __UINT64_MAX__ 0xffffffffffffffffULL
#define __FLT64X_DIG__ 18
#define __INT8_TYPE__ signed char
#define __GCC_ASM_FLAG_OUTPUTS__ 1
#define __FLT_RADIX__ 2
#define __INT_LEAST16_TYPE__ short int
#define __LDBL_EPSILON__ 1.08420217248550443400745280086994171e-19L
#define __UINTMAX_C(c) c ## ULL
#define __SIG_ATOMIC_MAX__ 0x7fffffff
#define __GCC_ATOMIC_WCHAR_T_LOCK_FREE 2
#define __SIZEOF_PTRDIFF_T__ 4
#define __pentium__ 1
#define __FLT32X_MANT_DIG__ 53
#define __FLT32X_MIN_EXP__ (-1021)
#define __DEC32_SUBNORMAL_MIN__ 0.000001E-95DF
#define __INT_FAST16_MAX__ 0x7fff
#define __FLT64_DIG__ 15
#define __UINT_FAST32_MAX__ 0xffffffffU
#define __UINT_LEAST64_TYPE__ long long unsigned int
#define __FLT_HAS_QUIET_NAN__ 1
#define __FLT_MAX_10_EXP__ 38
#define __LONG_MAX__ 0x7fffffffL
#define __FLT64X_HAS_DENORM__ 1
#define __DEC128_SUBNORMAL_MIN__ 0.000000000000000000000000000000001E-6143DL
#define __FLT_HAS_INFINITY__ 1
#define __UINT_FAST16_TYPE__ short unsigned int
#define __DEC64_MAX__ 9.999999999999999E384DD
#define __INT_FAST32_WIDTH__ 32
#define __CHAR16_TYPE__ short unsigned int
#define __PRAGMA_REDEFINE_EXTNAME 1
#define __SIZE_WIDTH__ 32
#define __SEG_FS 1
#define __INT_LEAST16_MAX__ 0x7fff
#define __DEC64_MANT_DIG__ 16
#define __INT64_MAX__ 0x7fffffffffffffffLL
#define __UINT_LEAST32_MAX__ 0xffffffffU
#define __SEG_GS 1
#define __FLT32_DENORM_MIN__ 1.40129846432481707092372958328991613e-45F32
#define __GCC_ATOMIC_LONG_LOCK_FREE 2
#define __SIG_ATOMIC_WIDTH__ 32
#define __INT_LEAST64_TYPE__ long long int
#define __INT16_TYPE__ short int
#define __INT_LEAST8_TYPE__ signed char
#define __STDC_VERSION__ 201112L
#define __DEC32_MAX_EXP__ 97
#define __INT_FAST8_MAX__ 0x7f
#define __FLT128_MAX__ 1.18973149535723176508575932662800702e+4932F128
#define __INTPTR_MAX__ 0x7fffffffL
#define __tune_pentium__ 1
#define __FLT64_HAS_QUIET_NAN__ 1
#define __FLT32_MIN_10_EXP__ (-37)
#define __FLT32X_DIG__ 15
#define DJGPP 2
#define __LDBL_MANT_DIG__ 64
#define __DBL_HAS_QUIET_NAN__ 1
#define __FLT64_HAS_INFINITY__ 1
#define __FLT64X_MAX__ 1.18973149535723176502126385303097021e+4932F64x
#define __SIG_ATOMIC_MIN__ (-__SIG_ATOMIC_MAX__ - 1)
#define __INTPTR_TYPE__ long int
#define __UINT16_TYPE__ short unsigned int
#define __WCHAR_TYPE__ short unsigned int
#define __SIZEOF_FLOAT__ 4
#define __UINTPTR_MAX__ 0xffffffffUL
#define __INT_FAST64_WIDTH__ 64
#define __DEC64_MIN_EXP__ (-382)
#define __FLT32_DECIMAL_DIG__ 9
#define __INT_FAST64_MAX__ 0x7fffffffffffffffLL
#define __GCC_ATOMIC_TEST_AND_SET_TRUEVAL 1
#define __FLT_DIG__ 6
#define __FLT32_HAS_INFINITY__ 1
#define __FLT64X_MAX_EXP__ 16384
#define __UINT_FAST64_TYPE__ long long unsigned int
#define __INT_MAX__ 0x7fffffff
#define __INT64_TYPE__ long long int
#define __FLT_MAX_EXP__ 128
#define __DBL_MANT_DIG__ 53
#define __SIZEOF_FLOAT128__ 16
#define __INT_LEAST64_MAX__ 0x7fffffffffffffffLL
#define __GCC_ATOMIC_CHAR16_T_LOCK_FREE 2
#define __DEC64_MIN__ 1E-383DD
#define __WINT_TYPE__ int
#define __UINT_LEAST32_TYPE__ unsigned int
#define __SIZEOF_SHORT__ 2
#define __LDBL_MIN_EXP__ (-16381)
#define __FLT64_MAX__ 1.79769313486231570814527423731704357e+308F64
#define __WINT_WIDTH__ 32
#define __INT_LEAST8_MAX__ 0x7f
#define __FLT32X_MAX_10_EXP__ 308
#define __LDBL_MAX_10_EXP__ 4932
#define __ATOMIC_RELAXED 0
#define __DBL_EPSILON__ ((double)2.22044604925031308084726333618164062e-16L)
#define __FLT128_MIN__ 3.36210314311209350626267781732175260e-4932F128
#define __UINT8_C(c) c
#define __FLT64_MAX_EXP__ 1024
#define __INT_LEAST32_TYPE__ int
#define __SIZEOF_WCHAR_T__ 2
#define __UINT64_TYPE__ long long unsigned int
#define __FLT128_HAS_QUIET_NAN__ 1
#define __INT_FAST8_TYPE__ signed char
#define __FLT64X_MIN__ 3.36210314311209350626267781732175260e-4932F64x
#define __GNUC_STDC_INLINE__ 1
#define __FLT64_HAS_DENORM__ 1
#define __FLT32_EPSILON__ 1.19209289550781250000000000000000000e-7F32
#define __DBL_DECIMAL_DIG__ 17
#define __STDC_UTF_32__ 1
#define __INT_FAST8_WIDTH__ 8
#define __DEC_EVAL_METHOD__ 2
#define __FLT32X_MAX__ 1.79769313486231570814527423731704357e+308F32x
#define __ORDER_BIG_ENDIAN__ 4321
#define __UINT32_C(c) c ## U
#define __INTMAX_MAX__ 0x7fffffffffffffffLL
#define __BYTE_ORDER__ __ORDER_LITTLE_ENDIAN__
#define __FLT_DENORM_MIN__ 1.40129846432481707092372958328991613e-45F
#define __INT8_MAX__ 0x7f
#define __MSDOS 1
#define __LONG_WIDTH__ 32
#define __UINT_FAST32_TYPE__ unsigned int
#define __CHAR32_TYPE__ unsigned int
#define __FLT_MAX__ 3.40282346638528859811704183484516925e+38F
#define __INT32_TYPE__ int
#define __SIZEOF_DOUBLE__ 8
#define __FLT_MIN_10_EXP__ (-37)
#define __FLT64_MIN__ 2.22507385850720138309023271733240406e-308F64
#define __INT_LEAST32_WIDTH__ 32
#define __INTMAX_TYPE__ long long int
#define i386 1
#define __DEC128_MAX_EXP__ 6145
#define __FLT32X_HAS_QUIET_NAN__ 1
#define __ATOMIC_CONSUME 1
#define __GNUC_MINOR__ 2
#define __INT_FAST16_WIDTH__ 16
#define __UINTMAX_MAX__ 0xffffffffffffffffULL
#define __DEC32_MANT_DIG__ 7
#define __FLT32X_DENORM_MIN__ 4.94065645841246544176568792868221372e-324F32x
#define __DBL_MAX_10_EXP__ 308
#define __LDBL_DENORM_MIN__ 3.64519953188247460252840593361941982e-4951L
#define __INT16_C(c) c
#define __STDC__ 1
#define __PTRDIFF_TYPE__ int
#define __ATOMIC_SEQ_CST 5
#define __UINT32_TYPE__ unsigned int
#define __FLT32X_MIN_10_EXP__ (-307)
#define __UINTPTR_TYPE__ long unsigned int
#define __DEC64_SUBNORMAL_MIN__ 0.000000000000001E-383DD
#define __DEC128_MANT_DIG__ 34
#define __LDBL_MIN_10_EXP__ (-4931)
#define __FLT128_EPSILON__ 1.92592994438723585305597794258492732e-34F128
#define __SIZEOF_LONG_LONG__ 8
#define __FLT128_DECIMAL_DIG__ 36
#define __GCC_ATOMIC_LLONG_LOCK_FREE 2
#define __FLT32X_MIN__ 2.22507385850720138309023271733240406e-308F32x
#define __LDBL_DIG__ 18
#define __FLT_DECIMAL_DIG__ 9
#define __UINT_FAST16_MAX__ 0xffff
#define __GCC_ATOMIC_SHORT_LOCK_FREE 2
#define __INT_LEAST64_WIDTH__ 64
#define __UINT_FAST8_TYPE__ unsigned char
#define __ATOMIC_ACQ_REL 4
#define __ATOMIC_RELEASE 3```

[SuperIlu]

PS: see https://github.com/SuperIlu/DosView/blob/main/3rdparty/jasper-version-4.0.0/cmake-djgpp.sh for the used CMake options and https://github.com/SuperIlu/DosView/blob/main/CMake-DJGPP-Toolchain.txt for the toolchain/cross compilation settings.

[mdadams]

I am still unclear what exactly the problem is. Which case should your environment be using in the #if...#endif? Is the issue actually with this line:

https://github.com/jasper-software/jasper/blob/master/src/libjasper/base/jas_malloc.c#L659 That is, does DJGPP/MSDOS not define _WIN32? So, do I need to change this line to:

elif defined(_WIN32) || defined(__MSDOS)

[SuperIlu]

My change simply makes jas_get_total_mem_size() return 0 in the else branch (memsize not available).

DJGPP does not define _WIN32 because it is pure DOS (no windows whatsoever).

without adding && !defined(__DJGPP__)) the code for Unix is compiled and sysconf() is not available on DJGPP/DOS

[mdadams]

I still don't understand why the existing code does not work. If you are crosscompiling for MSDOS then none of the following should be defined:

• JAS_WASI_LIBC
• __linux__
• __APPLE__
• __unix__
• _WIN32

If this is the case, then you should hit the "#else" case and 0 should be returned.

What am I missing here? Are you not setting the JAS_CROSSCOMPILING option? If not, everything will break horribly.

[SuperIlu]

DJGPP provides a (thin) unix compatible layer on top of MS-DOS. That is why __unix__ is set (see variable dump above).

You are correct, I do not set JAS_CROSSCOMPILING (seems I did miss that option), but I provide the cross compiling toolchain via CMAKE_TOOLCHAIN_FILE (as I do with other projects) and that just works fine (not only for jasper, but for other cross compiled CMake projects as well).

I can try settings CMAKE_TOOLCHAIN_FILE, too. But I'm not sure how that will fix the check in jas_get_total_mem_size() as __unix__ will still be defined (which is done by DJGPP/gcc and not by the stuff detected by CMake)...

[mdadams]

I'm sorry, but I misunderstood part of the problem that you are having. As long as CMake is correctly determining that you are crosscompiling, I think that setting JAS_CROSSCOMPILING may be unnecessary. If I have understood your problem correctly, the issue is not that CMake is failing to understand that you are crosscompiling, but rather that the incorrect code is being selected for the jas_get_total_mem_size function that you mentioned due to DJGPP pretending to be Unix (by defining unix). Does the commit that I just made on the mdadams-djgpp-fix branch resolve your build issue? If so, I will merge it to the master branch.

[SuperIlu]

No worries, if you never heard/seen DJGPP it is quite confusing that you are compiling for DOS, but it declares to be Unix as well :)

I'm not at my desktop RN, so I can't check right away, but looking at the commit I think the brackets are wrong?

Your code:

#elif defined(__unix__) && (!defined(__linux__) && !defined(__APPLE__) && !(defined(__DJGPP__))

I think it should be like this?

#elif defined(__unix__) && (!defined(__linux__) && !defined(__APPLE__) && !defined(__DJGPP__))

[mdadams]

Yes, you are right about the typo. I am sorry about that. I have just fixed the typo in commit 6504d161e1173be5d2f01906a192e0feb63c7e17 (on the mdadams-djgpp-fix branch). Please confirm that this fix resolves your issue. If it does, I will merge it into the master branch.

[mdadams]

I merged the fix to the master branch. So, I have closed this issue. If you still have problems, let me know and I can re-open this issue.

[SuperIlu]

I'll try it out after work, thanks.

[SuperIlu]

I can confirm that this now builds for me.

Thanks for caring

[mdadams]

Thanks for the confirmation. It is much appreciated.