windows-nt/Source/XPSP1/NT/com/ole32/common/cruntime/crt0dat.c
2020-09-26 16:20:57 +08:00

519 lines
14 KiB
C

/***
*crt0dat.c - 32-bit C run-time initialization/termination routines
*
* Copyright (c) 1986-1992, Microsoft Corporation. All rights reserved.
*
*Purpose:
* This module contains the routines _cinit, exit, and _exit
* for C run-time startup and termination. _cinit and exit
* are called from the _astart code in crt0.asm.
* This module also defines several data variables used by the
* runtime.
*
* [NOTE: Lock segment definitions are at end of module.]
*
* *** FLOATING POINT INITIALIZATION AND TERMINATION ARE NOT ***
* *** YET IMPLEMENTED IN THIS FILE ***
*
*Revision History:
* 06-28-89 PHG Module created, based on asm version
* 04-09-90 GJF Added #include <cruntime.h>. Made calling type
* explicit (_CALLTYPE1 or _CALLTYPE4). Also, fixed
* the copyright.
* 04-10-90 GJF Fixed compiler warnings (-W3).
* 05-21-90 GJF Added #undef _NFILE_ (temporary hack) and fixed the
* indents.
* 08-31-90 GJF Removed 32 from API names.
* 09-25-90 GJF Merged tree version with local (8-31 and 5-21 changes).
* 10-08-90 GJF New-style function declarators.
* 10-12-90 GJF Removed divide by 0 stuff.
* 10-18-90 GJF Added _pipech[] array.
* 11-05-90 GJF Added _umaskval.
* 12-04-90 GJF Added _osfinfo[] definition for Win32 target. Note that
* the Win32 support is still incomplete!
* 12-04-90 SRW Changed to include <oscalls.h> instead of <doscalls.h>
* 12-04-90 SRW Added _osfile back for win32. Changed _osfinfo from
* an array of structures to an array of 32-bit handles
* (_osfhnd)
* 12-28-90 SRW Added _CRUISER_ conditional around pack pragmas
* 01-29-91 GJF ANSI naming.
* 01-29-91 SRW Added call to GetFileType [_WIN32_]
* 02-18-91 SRW Removed duplicate defintion of _NFILE_ (see os2dll.h)
* 04-04-91 GJF Added definitions for _base[version|major|minor]
* (_WIN32_).
* 04-08-91 GJF Temporary hack for Win32/DOS folks - added HeapDestroy
* call to doexit to tear down the OS heap used by C
* heap.
* 04-09-91 PNT Added _MAC_ conditional
* 04-26-91 SRW Removed level 3 warnings
* 07-16-91 GJF Added fp initialization test-and-call [_WIN32_].
* 07-26-91 GJF Revised initialization and termination stuff. In
* particular, removed need for win32ini.c [_WIN32_].
* 08-07-91 GJF Added init. for FORTRAN runtime, if present [_WIN32_].
* 08-21-91 GJF Test _prmtmp against NULL, not _prmtmp().
* 08-21-91 JCR Added _exitflag, _endstdio, _cpumode, etc.
* 09-09-91 GJF Revised _doinitterm for C++ init. support and to make
* _onexit/atexit compatible with C++ needs.
* 09-16-91 GJF Must test __onexitend before calling _doinitterm.
* 10-29-91 GJF Force in floating point initialization for MIPS
* compiler [_WIN32_].
* 11-13-91 GJF FORTRAN needs _onexit/atexit init. before call thru
* _pFFinit.
* 01-10-92 GJF Merged. Also, added _C_Termination_Done [_WIN32_].
* 02-13-92 GJF Moved all lowio initialization to ioinit.c for Win32.
* 03-12-92 SKS Major changes to initialization/termination scheme
* 04-16-92 DJM POSIX support.
* 04-17-92 SKS Export _initterm() for CRTDLL model
* 05-07-92 DJM Removed _exit() from POSIX build.
* 06-03-92 GJF Temporarily restored call to FORTRAN init.
* 08-26-92 SKS Add _osver, _winver, _winmajor, _winminor
* 08-28-92 GJF Use unistd.h for POSIX build.
* 09-02-92 SKS Fix _onexit table traversal to be LIFO.
* Since table is built forward (my changes 03-12-92)
* the table must be traversed in reverse order.
* 10-30-92 TVB Force in floating point initialization for ALPHA
* compiler as was done for MIPS. [_WIN32_].
* 11-12-92 SKS Remove hard-coded call to FORTRAN initializer
* 05-11-93 SKS _C_Termination_Done is now used by DLLs in LIBC/LIBCMT
* models, not just in CRTDLL.DLL.
* Remove obsolete variable _child.
* 07-16-93 SRW ALPHA Merge
*
*******************************************************************************/
#include <windows.h>
#include <cruntime.h>
#include <internal.h>
#include <os2dll.h>
/* callable exit flag */
char _exitflag = 0;
/*
* flag indicating if C runtime termination has been done. set if exit,
* _exit, _cexit or _c_exit has been called. checked when _CRTDLL_INIT
* or user DLL's _CRT_INIT is called with DLL_PROCESS_DETACH.
*/
int _C_Termination_Done = FALSE;
/*
* useful type for initialization and termination declarations
*/
typedef void (_CALLTYPE1 *PF)(void);
/*
* NOTE: THE USE OF THE POINTERS DECLARED BELOW DEPENDS ON THE PROPERTIES
* OF C COMMUNAL VARIABLES. SPECIFICALLY, THEY ARE NON-NULL IFF THERE EXISTS
* A DEFINITION ELSEWHERE INITIALIZING THEM TO NON-NULL VALUES.
*/
/*
* pointers to initialization functions
*/
PF _FPinit; /* floating point init. */
/*
* pointers to initialization sections
*/
extern PF __xi_a[], __xi_z[]; /* C initializers */
extern PF __xc_a[], __xc_z[]; /* C++ initializers */
extern PF __xp_a[], __xp_z[]; /* C pre-terminators */
extern PF __xt_a[], __xt_z[]; /* C terminators */
#if defined(_M_MRX000) || defined(_M_ALPHA) || defined(_M_PPC)
/*
* For MIPS or ALPHA compilers, must explicitly force in and call the floating
* point initialization (those system always have floating-point hardware).
*/
extern void _CALLTYPE1 _fpmath(void);
#endif
/*
* pointers to the start and finish of the _onexit/atexit table
*/
PF *__onexitbegin;
PF *__onexitend;
/*
* static (internal) function that walks a table of function pointers,
* calling each entry between the two pointers, skipping NULL entries
*
* Needs to be exported for CRT DLL so that C++ initializers in the
* client EXE / DLLs can be initialized
*/
void _CALLTYPE4 _initterm(PF *, PF *);
#pragma data_seg()
/***
*_cinit - C initialization
*
*Purpose:
* This routine performs the shared DOS and Windows initialization.
* The following order of initialization must be preserved -
*
ifdef MTHREAD
* 0. Call OS2 to bump max file count (mthread only)
endif
* 1. Check for devices for file handles 0 - 2
* 2. Integer divide interrupt vector setup
* 3. General C initializer routines
*
*Entry:
* No parameters: Called from __crtstart and assumes data
* set up correctly there.
*
*Exit:
* Initializes C runtime data.
*
*Exceptions:
*
*******************************************************************************/
void _CALLTYPE1 _cinit (
void
)
{
/*
* initialize floating point package, if present
*/
#if defined(_M_MRX000) || defined(_M_ALPHA) || defined(_M_PPC)
/*
* The Mips, Alpha, and PPC compilers don't emit external reference to
* _fltused. Therefore, must always force in the floating point
* initialization.
*/
_fpmath();
#else
if ( _FPinit != NULL )
(*_FPinit)();
#endif
/*
* do initializations
*/
_initterm( __xi_a, __xi_z );
/*
* do C++ initializations
*/
_initterm( __xc_a, __xc_z );
}
/***
*exit(status), _exit(status), _cexit(void), _c_exit(void) - C termination
*
*Purpose:
*
* Entry points:
*
* exit(code): Performs all the C termination functions
* and terminates the process with the return code
* supplied by the user.
*
* _exit(code): Performs a quick exit routine that does not
* do certain 'high-level' exit processing. The _exit
* routine terminates the process with the return code
* supplied by the user.
*
* _cexit(): Performs the same C lib termination processing
* as exit(code) but returns control to the caller
* when done (i.e., does NOT terminate the process).
*
* _c_exit(): Performs the same C lib termination processing
* as _exit(code) but returns control to the caller
* when done (i.e., does NOT terminate the process).
*
* Termination actions:
*
* exit(), _cexit():
*
* 1. call user's terminator routines
* 2. call C runtime preterminators
*
* _exit(), _c_exit():
*
* 3. call C runtime terminators
* 4. return to DOS or caller
*
* Notes:
*
* The termination sequence is complicated due to the multiple entry
* points sharing the common code body while having different entry/exit
* sequences.
*
* Multi-thread notes:
*
* 1. exit() should NEVER be called when mthread locks are held.
* The exit() routine can make calls that try to get mthread locks.
*
* 2. _exit()/_c_exit() can be called from anywhere, with or without locks held.
* Thus, _exit() can NEVER try to get locks (otherwise, deadlock
* may occur). _exit() should always 'work' (i.e., the process
* should always terminate successfully).
*
* 3. Only one thread is allowed into the exit code (see _lockexit()
* and _unlockexit() routines).
*
*Entry:
* exit(), _exit()
* int status - exit status (0-255)
*
* _cexit(), _c_exit()
* <no input>
*
*Exit:
* exit(), _exit()
* <EXIT to DOS>
*
* _cexit(), _c_exit()
* Return to caller
*
*Uses:
*
*Exceptions:
*
*******************************************************************************/
/* worker routine prototype */
static void _CALLTYPE4 doexit (int code, int quick, int retcaller);
void _CALLTYPE1 exit (
int code
)
{
doexit(code, 0, 0); /* full term, kill process */
}
#ifndef _POSIX_
void _CALLTYPE1 _exit (
int code
)
{
doexit(code, 1, 0); /* quick term, kill process */
}
void _CALLTYPE1 _cexit (
void
)
{
doexit(0, 0, 1); /* full term, return to caller */
}
void _CALLTYPE1 _c_exit (
void
)
{
doexit(0, 1, 1); /* quick term, return to caller */
}
#endif /* _POSIX_ */
static void _CALLTYPE4 doexit (
int code,
int quick,
int retcaller
)
{
_lockexit(); /* assure only 1 thread in exit path */
/* save callable exit flag (for use by terminators) */
_exitflag = (char) retcaller; /* 0 = term, !0 = callable exit */
if (!quick) {
/*
* do _onexit/atexit() terminators
* (if there are any)
*
* These terminators MUST be executed in reverse order (LIFO)!
*
* NOTE:
* This code assumes that __onexitbegin points
* to the first valid onexit() entry and that
* __onexitend points past the last valid entry.
* If __onexitbegin == __onexitend, the table
* is empty and there are no routines to call.
*/
if (__onexitbegin) {
PF * pfend = __onexitend;
while ( -- pfend >= __onexitbegin )
/*
* if current table entry is non-NULL,
* call thru it.
*/
if ( *pfend != NULL )
(**pfend)();
}
/*
* do pre-terminators
*/
_initterm(__xp_a, __xp_z);
}
/*
* do terminators
*/
_initterm(__xt_a, __xt_z);
/********** FLOATING POINT TERMINATION SHOULD GO HERE ************/
/* return to OS/2 or to caller */
if (retcaller) {
_unlockexit(); /* unlock the exit code path */
return;
}
ExitProcess(code);
}
/***
* _lockexit - Aquire the exit code lock
*
*Purpose:
* Makes sure only one thread is in the exit code at a time.
* If a thread is already in the exit code, it must be allowed
* to continue. All other threads must pend.
*
* Notes:
*
* (1) It is legal for a thread that already has the lock to
* try and get it again(!). That is, consider the following
* sequence:
*
* (a) program calls exit()
* (b) thread locks exit code
* (c) user onexit() routine calls _exit()
* (d) same thread tries to lock exit code
*
* Since _exit() must ALWAYS be able to work (i.e., can be called
* from anywhere with no regard for locking), we must make sure the
* program does not deadlock at step (d) above.
*
* (2) If a thread executing exit() or _exit() aquires the exit lock,
* other threads trying to get the lock will pend forever. That is,
* since exit() and _exit() terminate the process, there is not need
* for them to unlock the exit code path.
*
* (3) Note that onexit()/atexit() routines call _lockexit/_unlockexit
* to protect mthread access to the onexit table.
*
* (4) The _lockexit/_unlockexit routines are very complicated in 286
* OS/2 since a thread that held a lock could not request the lock again.
* The 32-bit OS/2 semaphore calls DO allow a single thread to aquire the
* same lock multiple times* thus, this version is straight forward.
*
*Entry: <none>
*
*Exit:
* Calling thread has exit code path locked on return.
*
*Exceptions:
*
*******************************************************************************/
void _CALLTYPE1 _lockexit (
void
)
{
_mlock(_EXIT_LOCK1);
}
/***
* _unlockexit - Release exit code lock
*
*Purpose:
* [See _lockexit() description above.]
*
* This routine is called by _cexit(), _c_exit(), and onexit()/atexit().
* The exit() and _exit() routines never unlock the exit code path since
* they are terminating the process.
*
*Entry:
* Exit code path is unlocked.
*
*Exit:
*
*Exceptions:
*
*******************************************************************************/
void _CALLTYPE1 _unlockexit (
void
)
{
_munlock(_EXIT_LOCK1);
}
/***
* static void _initterm(PF * pfbegin, PF * pfend) - call entries in
* function pointer table
*
*Purpose:
* Walk a table of function pointers, calling each entry, as follows:
*
* 1. walk from beginning to end, pfunctbl is assumed to point
* to the beginning of the table, which is currently a null entry,
* as is the end entry.
* 2. skip NULL entries
* 3. stop walking when the end of the table is encountered
*
*Entry:
* PF *pfbegin - pointer to the beginning of the table (first valid entry).
* PF *pfend - pointer to the end of the table (after last valid entry).
*
*Exit:
* No return value
*
*Notes:
* This routine must be exported in the CRT DLL model so that the client
* EXE and client DLL(s) can call it to initialize their C++ constructors.
*
*Exceptions:
* If either pfbegin or pfend is NULL, or invalid, all bets are off!
*
*******************************************************************************/
void _CALLTYPE4 _initterm (
PF * pfbegin,
PF * pfend
)
{
/*
* walk the table of function pointers from the bottom up, until
* the end is encountered. Do not skip the first entry. The initial
* value of pfbegin points to the first valid entry. Do not try to
* execute what pfend points to. Only entries before pfend are valid.
*/
while ( pfbegin < pfend )
{
/*
* if current table entry is non-NULL, call thru it.
*/
if ( *pfbegin != NULL )
(**pfbegin)();
++pfbegin;
}
}