LoadLibraryEx ignores side-by-side manifest

问题

Does LoadLibraryEx function use side-by-side manifests? I have bar.dll with embedded SxS manifest, and that manifest describes version of this bar.dll, other dll file foo.dll has manifest that lists bar.dll as dependency, with specified version. But when I try to load bar.dll from foo.dll with LoadLibraryEx("bar.dll", NULL, 0) I see (with enabled sls with gflags) that it ignores these manifests, and loads first version of bar.dll that it sees in searchpath, if I define ISOLATION_AWARE_ENABLED and use LoadLibrary it finds right version, but this ISOLATION_AWARE_ENABLED doesn't affect behaviour of LoadLibraryEx, I need to load right version with LoadLibraryEx because LoadLibraryEx is used implicitly for delayed loading of dll's. Is LoadLibraryEx supposed to work like this, or is it some problem in my project configuration?

foo dll

<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<assembly xmlns="urn:schemas-microsoft-com:asm.v1" manifestVersion="1.0">
<assemblyIdentity name="foo" version="0.1.2.3" type="win32"/>
<dependency>
    <dependentAssembly>
        <assemblyIdentity name="bar" version="0.1.2.3" type="win32" />
    </dependentAssembly>
</dependency>
<file name="foo.dll">
</file>
</assembly> 

bar.dll

<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<assembly xmlns="urn:schemas-microsoft-com:asm.v1" manifestVersion="1.0">
<assemblyIdentity name="bar" version="0.1.2.3" type="win32"/>
<file name="bar.dll">
</file>
</assembly> 

回答1:

LoadLibrary used active activation context of the calling thread. but which is this context ? why it must be from your foo.dll ? why not from xyz.dll or from exe ? really most time active activation context was exactly from exe.

if dll have own manifest - system create activation context for this dll and save it (until dll will be unloaded) but not make it active. and this is obviously - we have multiple dlls in process, but active context only one - from which dll select it ? from exe. however system activate (make it current active) dll activation context before call it entry point. and deactivate it after entry point return. but say inside another dll functions - (who called it ?) the context already not from your dll.

so solution must be next:

define 2 global variables in dll:

BOOL gActCtx;
HANDLE ghActCtx

on DLL_PROCESS_ATTACH save current activation context (it from your dll manifest)

gActCtx = GetCurrentActCtx(&ghActCtx);

free it on DLL_PROCESS_DETACH

if (gActCtx) ReleaseActCtx(ghActCtx);

and when you need load bar.dll do next:

if (gActCtx)
{
    ULONG_PTR Cookie;

    if (ActivateActCtx(ghActCtx, &Cookie))
    {
        LoadLibraryExW(L"bar.dll", NULL, 0);

        DeactivateActCtx(0, Cookie);
    }
}

来源：https://stackoverflow.com/questions/48308530/loadlibraryex-ignores-side-by-side-manifest