/* * tkWin32Dll.c -- * * This file contains a stub dll entry point. * * Copyright (c) 1995 Sun Microsystems, Inc. * * See the file "license.terms" for information on usage and redistribution of * this file, and for a DISCLAIMER OF ALL WARRANTIES. * * RCS: @(#) $Id: tkWin32Dll.c,v 1.12.4.1 2010/12/13 21:23:59 nijtmans Exp $ */ #include "tkWinInt.h" #ifndef STATIC_BUILD #ifdef HAVE_NO_SEH /* * Unlike Borland and Microsoft, we don't register exception handlers by * pushing registration records onto the runtime stack. Instead, we register * them by creating an EXCEPTION_REGISTRATION within the activation record. */ typedef struct EXCEPTION_REGISTRATION { struct EXCEPTION_REGISTRATION *link; EXCEPTION_DISPOSITION (*handler)( struct _EXCEPTION_RECORD*, void*, struct _CONTEXT*, void*); void *ebp; void *esp; int status; } EXCEPTION_REGISTRATION; /* * Need to add noinline flag to DllMain declaration so that gcc -O3 does not * inline asm code into DllEntryPoint and cause a compile time error because * of redefined local labels. */ BOOL APIENTRY DllMain(HINSTANCE hInst, DWORD reason, LPVOID reserved) __attribute__ ((noinline)); #else /* !HAVE_NO_SEH */ /* * The following declaration is for the VC++ DLL entry point. */ BOOL APIENTRY DllMain(HINSTANCE hInst, DWORD reason, LPVOID reserved); #endif /* HAVE_NO_SEH */ /* *---------------------------------------------------------------------- * * DllEntryPoint -- * * This wrapper function is used by Borland to invoke the initialization * code for Tk. It simply calls the DllMain routine. * * Results: * See DllMain. * * Side effects: * See DllMain. * *---------------------------------------------------------------------- */ BOOL APIENTRY DllEntryPoint( HINSTANCE hInst, /* Library instance handle. */ DWORD reason, /* Reason this function is being called. */ LPVOID reserved) /* Not used. */ { return DllMain(hInst, reason, reserved); } /* *---------------------------------------------------------------------- * * DllMain -- * * DLL entry point. It is only necessary to specify our dll here so that * resources are found correctly. Otherwise Tk will initialize and clean * up after itself through other methods, in order to be consistent * whether the build is static or dynamic. * * Results: * Always TRUE. * * Side effects: * This might call some synchronization functions, but MSDN documentation * states: "Waiting on synchronization objects in DllMain can cause a * deadlock." * *---------------------------------------------------------------------- */ BOOL APIENTRY DllMain( HINSTANCE hInstance, DWORD reason, LPVOID reserved) { #ifdef HAVE_NO_SEH EXCEPTION_REGISTRATION registration; #endif /* * If we are attaching to the DLL from a new process, tell Tk about the * hInstance to use. */ switch (reason) { case DLL_PROCESS_ATTACH: DisableThreadLibraryCalls(hInstance); TkWinSetHINSTANCE(hInstance); break; case DLL_PROCESS_DETACH: /* * Protect the call to TkFinalize in an SEH block. We can't be * guarenteed Tk is always being unloaded from a stable condition. */ #ifdef HAVE_NO_SEH # ifdef __WIN64 __asm__ __volatile__ ( /* * Construct an EXCEPTION_REGISTRATION to protect the call to * TkFinalize */ "leaq %[registration], %%rdx" "\n\t" "movq %%gs:0, %%rax" "\n\t" "movq %%rax, 0x0(%%edx)" "\n\t" /* link */ "leaq 1f, %%rax" "\n\t" "movq %%rax, 0x8(%%rdx)" "\n\t" /* handler */ "movq %%rbp, 0x10(%%rdx)" "\n\t" /* ebp */ "movq %%rsp, 0x18(%%rdx)" "\n\t" /* esp */ "movl %[error], 0x20(%%rdx)" "\n\t" /* status */ /* * Link the EXCEPTION_REGISTRATION on the chain */ "movq %%rdx, %%gs:0" "\n\t" /* * Call TkFinalize */ "movq $0x0, 0x0(%%esp)" "\n\t" "call TkFinalize" "\n\t" /* * Come here on a normal exit. Recover the EXCEPTION_REGISTRATION * and store a TCL_OK status */ "movq %%gs:0, %%rdx" "\n\t" "movl %[ok], %%eax" "\n\t" "movl %%eax, 0x20(%%rdx)" "\n\t" "jmp 2f" "\n" /* * Come here on an exception. Get the EXCEPTION_REGISTRATION that * we previously put on the chain. */ "1:" "\t" "movq %%gs:0, %%rdx" "\n\t" "movq 0x10(%%rdx), %%rdx" "\n\t" /* * Come here however we exited. Restore context from the * EXCEPTION_REGISTRATION in case the stack is unbalanced. */ "2:" "\t" "movq 0x18(%%rdx), %%rsp" "\n\t" "movq 0x10(%%rdx), %%rbp" "\n\t" "movq 0x0(%%rdx), %%rax" "\n\t" "movq %%rax, %%gs:0" "\n\t" : /* No outputs */ : [registration] "m" (registration), [ok] "i" (TCL_OK), [error] "i" (TCL_ERROR) : "%rax", "%rbx", "%rcx", "%rdx", "%rsi", "%rdi", "memory" ); # else __asm__ __volatile__ ( /* * Construct an EXCEPTION_REGISTRATION to protect the call to * TkFinalize */ "leal %[registration], %%edx" "\n\t" "movl %%fs:0, %%eax" "\n\t" "movl %%eax, 0x0(%%edx)" "\n\t" /* link */ "leal 1f, %%eax" "\n\t" "movl %%eax, 0x4(%%edx)" "\n\t" /* handler */ "movl %%ebp, 0x8(%%edx)" "\n\t" /* ebp */ "movl %%esp, 0xc(%%edx)" "\n\t" /* esp */ "movl %[error], 0x10(%%edx)" "\n\t" /* status */ /* * Link the EXCEPTION_REGISTRATION on the chain */ "movl %%edx, %%fs:0" "\n\t" /* * Call TkFinalize */ "movl $0x0, 0x0(%%esp)" "\n\t" "call _TkFinalize" "\n\t" /* * Come here on a normal exit. Recover the EXCEPTION_REGISTRATION * and store a TCL_OK status */ "movl %%fs:0, %%edx" "\n\t" "movl %[ok], %%eax" "\n\t" "movl %%eax, 0x10(%%edx)" "\n\t" "jmp 2f" "\n" /* * Come here on an exception. Get the EXCEPTION_REGISTRATION that * we previously put on the chain. */ "1:" "\t" "movl %%fs:0, %%edx" "\n\t" "movl 0x8(%%edx), %%edx" "\n" /* * Come here however we exited. Restore context from the * EXCEPTION_REGISTRATION in case the stack is unbalanced. */ "2:" "\t" "movl 0xc(%%edx), %%esp" "\n\t" "movl 0x8(%%edx), %%ebp" "\n\t" "movl 0x0(%%edx), %%eax" "\n\t" "movl %%eax, %%fs:0" "\n\t" : /* No outputs */ : [registration] "m" (registration), [ok] "i" (TCL_OK), [error] "i" (TCL_ERROR) : "%eax", "%ebx", "%ecx", "%edx", "%esi", "%edi", "memory" ); # endif #else /* HAVE_NO_SEH */ __try { /* * Run and remove our exit handlers, if they haven't already been * run. Just in case we are being unloaded prior to Tcl (it can * happen), we won't leave any dangling pointers hanging around * for when Tcl gets unloaded later. */ TkFinalize(NULL); } __except (EXCEPTION_EXECUTE_HANDLER) { /* empty handler body. */ } #endif break; } return TRUE; } #endif /* !STATIC_BUILD */ /* * Local Variables: * mode: c * c-basic-offset: 4 * fill-column: 78 * End: */