link failure on MSVC

[oneeyeman1]

Hi,

As directed in one of my previous questions in order to get SQL Anywhere SDK for Windows I downloaded the full server package and iinstalled it on my development machine.

I then added the project  to my MSVC solution, add some code and then looking at the samples\build.bat I modified the options as follows:

C/C++ options:

/GS /analyze- /W4 /Zc:wchar_t /I"C:\Program Files (x86)\Visual Leak Detector\include" /I"..\dbinterface" /I"C:\Program Files\SQL Anywhere 17\SDK\include" /Zi /Gm- /Od /Fd"vc_mswuddll\sqlany_dll.pdb" /Zc:inline /fp:precise /D "__MEMORYLEAKS__" /D "WIN32" /D "_USRDLL" /D "DLL_EXPORTS" /D "_DEBUG" /D "_CRT_SECURE_NO_DEPRECATE=1" /D "_CRT_NON_CONFORMING_SWPRINTFS=1" /D "_SCL_SECURE_NO_WARNINGS=1" /D "_SACAPI_VERSION=6" /D "_UNICODE" /D "MY_DLL_BUILDING" /D "_WINDLL" /D "UNICODE" /errorReport:prompt /WX- /Zc:forScope /RTC1 /GR /Gd /Oy- /MDd /FC /Fa"vc_mswuddll\" /EHsc /nologo /Fo"vc_mswuddll\" /Fp"vc_mswuddll\sqlany_dll.pch" /diagnostics:classic

Linker options:

/OUT:"..\dbhandler\vc_mswuddll\sqlany.dll" /MANIFEST /NXCOMPAT /PDB:"vc_mswuddll\sqlany_dll.pdb" /DYNAMICBASE "vld.lib" "dbinterface.lib" "user32.lib" "gdi32.lib" "advapi32.lib" "dbcapi.lib" "kernel32.lib" "winspool.lib" "comdlg32.lib" "shell32.lib" "ole32.lib" "oleaut32.lib" "uuid.lib" "odbc32.lib" "odbccp32.lib" /IMPLIB:"vc_mswuddll\sqlany_dll.lib" /DEBUG /DLL /MACHINE:X86 /SAFESEH /INCREMENTAL /PGD:"C:\Users\Igor\OneDrive\Documents\dbhandler_app\libsqlany\vc_mswuddll\sqlany_dll.pgd" /MANIFESTUAC:"level='asInvoker' uiAccess='false'" /ManifestFile:"vc_mswuddll\sqlany_dll.dll.intermediate.manifest" /ERRORREPORT:PROMPT /NOLOGO /LIBPATH:"..\dbhandler\Debug" /LIBPATH:"C:\Program Files\SQL Anywhere 17\SDK\Lib\X86" /LIBPATH:"C:\Program Files (x86)\Visual Leak Detector\lib\Win32" /TLBID:1

Trying to build it I received the following:

1> database_sqlany.obj : error LNK2019: unresolved external symbol "int __cdecl sqlany_initialize_interface(struct SQLAnywhereInterface *,char const *)" (?sqlany_initialize_interface@@YAHPAUSQLAnywhereInterface@@PBD@Z) referenced in function "public: __thiscall SQLAnyDatabase::SQLAnyDatabase(int,class std::basic_string<wchar_t,struct std::char_traits<wchar_t>,class std::allocator<wchar_t> > const &)" (??0SQLAnyDatabase@@QAE@HABV?$basic_string@_WU?$char_traits@_W@std@@V?$allocator@_W@2@@std@@@Z)
1> database_sqlany.obj : error LNK2019: unresolved external symbol "void __cdecl sqlany_finalize_interface(struct SQLAnywhereInterface *)" (?sqlany_finalize_interface@@YAXPAUSQLAnywhereInterface@@@Z) referenced in function "public: __thiscall SQLAnyDatabase::SQLAnyDatabase(int,class std::basic_string<wchar_t,struct std::char_traits<wchar_t>,class std::allocator<wchar_t> > const &)" (??0SQLAnyDatabase@@QAE@HABV?$basic_string@_WU?$char_traits@_W@std@@V?$allocator@_W@2@@std@@@Z)
1> ..\dbhandler\vc_mswuddll\sqlany.dll : fatal error LNK1120: 2 unresolved externals

What am I missing?

Thank you,

P.S.:

In my code I follow the sample code which have:

[code]

if( !sqlany_initialize_interface( &api, NULL ) ) {
printf( "Could not initialize the interface!\n" );
exit( 0 );
}

if( !api.sqlany_init( "MyAPP", SQLANY_API_VERSION_1, &max_api_ver )) {
printf( "Failed to initialize the interface! Supported version = %d\n", max_api_ver );
sqlany_finalize_interface( &api );
return -1;
}

/* A connection object needs to be created first */
sqlany_conn = api.sqlany_new_connection();

[/code]

[oneeyeman1]

Trying to answer my own question 😉

It looks like the samples building includes the additional files inside SDK\dbcapi directory which contains declaration/definition of API in question. I copied those 3 files but I now have compilation error. I did change the project settings to use /TP to compile as C++ code.

I am defining UNICODE and so compiling I get:

  1>c:\users\igor\onedrive\documents\dbhandler_app\libsqlany\sacapidll.c(57): error C2664: 'HMODULE LoadLibraryW(LPCWSTR)': cannot convert argument 1 from 'const char *' to 'LPCWSTR'

I am hesitant to change it, since it is not my code and I want to be on the safe side.

However I do believe that this needs to be fixed. Something like:

#ifdef _UNICODE

static void *loadLibrary(LPCWSTR name)

#else

static void *loadLiibrary(const char *name)

#endif

(Above is untested)

I'm sure someone on this forum can submit this as a bug/improvement.

Thank you.

[oneeyeman1]

@chris_keating,

thx for the suggestion.

There are couple of things to consider.

1. The sample code uses the interface files and so use dynamic linking.

2. My project uses dynamic linking all the way thru and for other DBMSes as well.

3. Also it defines _UNICODE and so I had to fix building my code with it.

i understand that 3 will be eliminated and 2 is not really an argument. But I’m not sure what consequences will be if I use it as static library.

Thank you.

[oneeyeman1]

@chris_keating, yes. Why?

[chris_keating]

I don't know the context for your question "Why".

[oneeyeman1]

@chris_keating,

I replied to this comment:

[quote]

I see this in your output "/LIBPATH:"C:\Program Files\SQL Anywhere 17\SDK\Lib\X86". Are you really building a 32-bit application?

[/quote]

Thank you.

[chris_keating]

Use the static library.  To do so, do not use the sacapidll.* files but include the sacapi.h header only. You are already referencing the static library dbcapi.lib in the linker options.  Additionally, you will not use the SQLAnywhereInterface in code.  As a result, don't call sqlany_initialize_interface or sqlany_finalize_interface methods. Additionally, the other APIs can be invoked as is, for example, the  api.sqlany_init would get called without the api. Your code snippet would be rewritten as:

if( !sqlany_init( "MyAPP", SQLANY_API_VERSION_1, &max_api_ver )) {
    printf( "[ERROR] Failed to initialize the interface! Supported version = %d\n", max_api_ver );
    exit( EXIT_FAILURE );
}

/* A connection object needs to be created first */
sqlany_conn = sqlany_new_connection();
if( sqlany_conn ) {

[jack_schueler]

I see this in your output "/LIBPATH:"C:\Program Files\SQL Anywhere 17\SDK\Lib\X86". Are you really building a 32-bit application?

[chris_keating]

A discussion today pointed out that the sacapidll.c  can be compiled without requiring it to be UNICODE. I don't use MSVC IDE for development but just the command link cl and link executables but here is an example batch that compiles the DBCAPI connecting.cpp example as UNICODE (see __MCUNICODE definition)  and the sacapidll.c without UNICODE .  You can likely do the same in MSVC but I leave that as an exercise to the reader. 

setlocal

set __MCOPTS={compiler options excluding UNICODE}
set __MCUNICODE=/D_UNICODE /DUNICODE
set __LNKOPTS={linker options}

cl %__MCOPTS% %__MCUNICODE% -c /Tp connecting.cpp
cl %__MCOPTS% -c /Tp %SQLANY17%\SDK\dbcapi\sacapidll.c
link /out:connect%PLAT_EXT%.exe connecting.obj sacapidll.obj %__LNKOPTS%

endlocal