newlib/winsup/cygwin/lib/_cygwin_crt0_common.cc

191 lines
6.2 KiB
C++

/* _cygwin_crt0_common.cc: common crt0 function for cygwin crt0's.
This file is part of Cygwin.
This software is a copyrighted work licensed under the terms of the
Cygwin license. Please consult the file "CYGWIN_LICENSE" for
details. */
#include "winsup.h"
#include "crt0.h"
#include "cygwin-cxx.h"
/* Weaken these declarations so the references don't pull in C++ dependencies
unnecessarily. */
#define WEAK __attribute__ ((weak))
#ifdef __x86_64__
#define REAL_ZNWX "__real__Znwm"
#define REAL_ZNAX "__real__Znam"
#define REAL_ZNWX_NOTHROW_T "__real__ZnwmRKSt9nothrow_t"
#define REAL_ZNAX_NOTHROW_T "__real__ZnamRKSt9nothrow_t"
#else
#define REAL_ZNWX "___real__Znwj"
#define REAL_ZNAX "___real__Znaj"
#define REAL_ZNWX_NOTHROW_T "___real__ZnwjRKSt9nothrow_t"
#define REAL_ZNAX_NOTHROW_T "___real__ZnajRKSt9nothrow_t"
#endif
#define REAL_ZDLPV _SYMSTR (__real__ZdlPv)
#define REAL_ZDAPV _SYMSTR (__real__ZdaPv)
#define REAL_ZDLPV_NOTHROW_T _SYMSTR (__real__ZdlPvRKSt9nothrow_t)
#define REAL_ZDAPV_NOTHROW_T _SYMSTR (__real__ZdaPvRKSt9nothrow_t)
/* Use asm names to bypass the --wrap that is being applied to redirect all other
references to these operators toward the redirectors in the Cygwin DLL; this
way we can record what definitions were visible at final link time but still
send all calls to the redirectors. */
extern WEAK void *operator new(std::size_t sz) throw (std::bad_alloc)
__asm__ (REAL_ZNWX);
extern WEAK void *operator new[](std::size_t sz) throw (std::bad_alloc)
__asm__ (REAL_ZNAX);
extern WEAK void operator delete(void *p) throw()
__asm__ (REAL_ZDLPV);
extern WEAK void operator delete[](void *p) throw()
__asm__ (REAL_ZDAPV);
extern WEAK void *operator new(std::size_t sz, const std::nothrow_t &nt) throw()
__asm__ (REAL_ZNWX_NOTHROW_T);
extern WEAK void *operator new[](std::size_t sz, const std::nothrow_t &nt) throw()
__asm__ (REAL_ZNAX_NOTHROW_T);
extern WEAK void operator delete(void *p, const std::nothrow_t &nt) throw()
__asm__ (REAL_ZDLPV_NOTHROW_T);
extern WEAK void operator delete[](void *p, const std::nothrow_t &nt) throw()
__asm__ (REAL_ZDAPV_NOTHROW_T);
/* Avoid an info message from linker when linking applications. */
extern __declspec(dllimport) struct _reent *_impure_ptr;
/* Initialised in _cygwin_dll_entry. */
extern int __dynamically_loaded;
#undef environ
extern "C"
{
#ifndef __x86_64__
char **environ;
#endif
int _fmode;
extern char __RUNTIME_PSEUDO_RELOC_LIST__;
extern char __RUNTIME_PSEUDO_RELOC_LIST_END__;
#ifdef __x86_64__
extern char __image_base__;
#define _image_base__ __image_base__
#else
extern char _image_base__;
#endif
struct per_process_cxx_malloc __cygwin_cxx_malloc =
{
&(operator new), &(operator new[]),
&(operator delete), &(operator delete[]),
&(operator new), &(operator new[]),
&(operator delete), &(operator delete[])
};
/* Set up pointers to various pieces so the dll can then use them,
and then jump to the dll. */
int __stdcall
_cygwin_crt0_common (MainFunc f, per_process *u)
{
per_process *newu = (per_process *) cygwin_internal (CW_USER_DATA);
bool uwasnull;
/* u is non-NULL if we are in a DLL, and NULL in the main exe.
newu is the Cygwin DLL's internal per_process and never NULL. */
if (u != NULL)
uwasnull = false; /* Caller allocated space for per_process structure. */
else
{
u = newu; /* Using DLL built-in per_process. */
uwasnull = true; /* Remember for later. */
}
/* The version numbers are the main source of compatibility checking.
As a backup to them, we use the size of the per_process struct. */
u->magic_biscuit = sizeof (per_process);
/* cygwin.dll version number in effect at the time the app was created. */
u->dll_major = CYGWIN_VERSION_DLL_MAJOR;
u->dll_minor = CYGWIN_VERSION_DLL_MINOR;
u->api_major = CYGWIN_VERSION_API_MAJOR;
u->api_minor = CYGWIN_VERSION_API_MINOR;
u->ctors = &__CTOR_LIST__;
u->dtors = &__DTOR_LIST__;
#ifndef __x86_64__
u->envptr = &environ;
#endif
if (uwasnull)
_impure_ptr = u->impure_ptr; /* Use field initialized in newer DLLs. */
else
u->impure_ptr_ptr = &_impure_ptr; /* Older DLLs need this. */
u->main = f;
/* These functions are executed prior to main. They are just stubs unless the
user overrides them. */
u->premain[0] = cygwin_premain0;
u->premain[1] = cygwin_premain1;
u->premain[2] = cygwin_premain2;
u->premain[3] = cygwin_premain3;
u->fmode_ptr = &_fmode;
/* Unused */
u->initial_sp = NULL;
/* Remember whatever the user linked his application with - or
point to entries in the dll. */
u->malloc = &malloc;
u->free = &free;
u->realloc = &realloc;
u->calloc = &calloc;
u->posix_memalign = &posix_memalign;
/* Likewise for the C++ memory operators, if any, but not if we
were dlopen()'d, as we might get dlclose()'d and that would
leave stale function pointers behind. */
if (newu && newu->cxx_malloc && !__dynamically_loaded)
{
/* Inherit what we don't override. */
#define CONDITIONALLY_OVERRIDE(MEMBER) \
if (!__cygwin_cxx_malloc.MEMBER) \
__cygwin_cxx_malloc.MEMBER = newu->cxx_malloc->MEMBER;
CONDITIONALLY_OVERRIDE(oper_new);
CONDITIONALLY_OVERRIDE(oper_new__);
CONDITIONALLY_OVERRIDE(oper_delete);
CONDITIONALLY_OVERRIDE(oper_delete__);
CONDITIONALLY_OVERRIDE(oper_new_nt);
CONDITIONALLY_OVERRIDE(oper_new___nt);
CONDITIONALLY_OVERRIDE(oper_delete_nt);
CONDITIONALLY_OVERRIDE(oper_delete___nt);
/* Now update the resulting set into the global redirectors. */
*newu->cxx_malloc = __cygwin_cxx_malloc;
}
/* Setup the module handle so fork can get the path name. */
u->hmodule = GetModuleHandle (0);
/* variables for fork */
#ifdef __x86_64__
u->data_start = &__data_start__;
u->data_end = &__data_end__;
u->bss_start = &__bss_start__;
u->bss_end = &__bss_end__;
#else
u->data_start = &_data_start__;
u->data_end = &_data_end__;
u->bss_start = &_bss_start__;
u->bss_end = &_bss_end__;
#endif
u->pseudo_reloc_start = &__RUNTIME_PSEUDO_RELOC_LIST__;
u->pseudo_reloc_end = &__RUNTIME_PSEUDO_RELOC_LIST_END__;
u->image_base = &_image_base__;
/* This is actually a dummy call to force the linker to load this
symbol for older apps which need it. */
_pei386_runtime_relocator (NULL);
return 1;
}
} /* "C" */