newlib/winsup/cygwin/dcrt0.cc

1368 lines
39 KiB
C++

/* dcrt0.cc -- essentially the main() for the Cygwin dll
Copyright 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006,
2007, 2008, 2009, 2010, 2011, 2012, 2013, 2014 Red Hat, Inc.
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 "miscfuncs.h"
#include <unistd.h>
#include <stdlib.h>
#include "glob.h"
#include <ctype.h>
#include <locale.h>
#include "environ.h"
#include "sigproc.h"
#include "pinfo.h"
#include "cygerrno.h"
#define NEED_VFORK
#include "perprocess.h"
#include "path.h"
#include "fhandler.h"
#include "dtable.h"
#include "cygheap.h"
#include "child_info_magic.h"
#include "cygtls.h"
#include "shared_info.h"
#include "cygwin_version.h"
#include "dll_init.h"
#include "heap.h"
#include "tls_pbuf.h"
#include "exception.h"
#include "cygxdr.h"
#include "fenv.h"
#include "ntdll.h"
#include "wow64.h"
#define MAX_AT_FILE_LEVEL 10
#define PREMAIN_LEN (sizeof (user_data->premain) / sizeof (user_data->premain[0]))
extern "C" void cygwin_exit (int) __attribute__ ((noreturn));
extern "C" void __sinit (_reent *);
static int NO_COPY envc;
static char NO_COPY **envp;
bool NO_COPY jit_debug;
static void
do_global_dtors ()
{
void (**pfunc) () = user_data->dtors;
if (pfunc)
{
user_data->dtors = NULL;
while (*++pfunc)
(*pfunc) ();
}
}
static void __stdcall
do_global_ctors (void (**in_pfunc)(), int force)
{
if (!force && in_forkee)
return; // inherit constructed stuff from parent pid
/* Run ctors backwards, so skip the first entry and find how many
there are, then run them. */
void (**pfunc) () = in_pfunc;
while (*++pfunc)
;
while (--pfunc > in_pfunc)
(*pfunc) ();
}
/*
* Replaces @file in the command line with the contents of the file.
* There may be multiple @file's in a single command line
* A \@file is replaced with @file so that echo \@foo would print
* @foo and not the contents of foo.
*/
static bool __stdcall
insert_file (char *name, char *&cmd)
{
HANDLE f;
DWORD size;
tmp_pathbuf tp;
PWCHAR wname = tp.w_get ();
sys_mbstowcs (wname, NT_MAX_PATH, name + 1);
f = CreateFileW (wname,
GENERIC_READ, /* open for reading */
FILE_SHARE_VALID_FLAGS, /* share for reading */
&sec_none_nih, /* default security */
OPEN_EXISTING, /* existing file only */
FILE_ATTRIBUTE_NORMAL, /* normal file */
NULL); /* no attr. template */
if (f == INVALID_HANDLE_VALUE)
{
debug_printf ("couldn't open file '%s', %E", name);
return false;
}
/* This only supports files up to about 4 billion bytes in
size. I am making the bold assumption that this is big
enough for this feature */
size = GetFileSize (f, NULL);
if (size == 0xFFFFFFFF)
{
CloseHandle (f);
debug_printf ("couldn't get file size for '%s', %E", name);
return false;
}
int new_size = strlen (cmd) + size + 2;
char *tmp = (char *) malloc (new_size);
if (!tmp)
{
CloseHandle (f);
debug_printf ("malloc failed, %E");
return false;
}
/* realloc passed as it should */
DWORD rf_read;
BOOL rf_result;
rf_result = ReadFile (f, tmp, size, &rf_read, NULL);
CloseHandle (f);
if (!rf_result || (rf_read != size))
{
free (tmp);
debug_printf ("ReadFile failed, %E");
return false;
}
tmp[size++] = ' ';
strcpy (tmp + size, cmd);
cmd = tmp;
return true;
}
static inline int
isquote (char c)
{
char ch = c;
return ch == '"' || ch == '\'';
}
/* Step over a run of characters delimited by quotes */
static /*__inline*/ char *
quoted (char *cmd, int winshell)
{
char *p;
char quote = *cmd;
if (!winshell)
{
char *p;
strcpy (cmd, cmd + 1);
if (*(p = strchrnul (cmd, quote)))
strcpy (p, p + 1);
return p;
}
const char *s = quote == '\'' ? "'" : "\\\"";
/* This must have been run from a Windows shell, so preserve
quotes for globify to play with later. */
while (*cmd && *++cmd)
if ((p = strpbrk (cmd, s)) == NULL)
{
cmd = strchr (cmd, '\0'); // no closing quote
break;
}
else if (*p == '\\')
cmd = ++p;
else if (quote == '"' && p[1] == '"')
{
*p = '\\';
cmd = ++p; // a quoted quote
}
else
{
cmd = p + 1; // point to after end
break;
}
return cmd;
}
/* Perform a glob on word if it contains wildcard characters.
Also quote every character between quotes to force glob to
treat the characters literally. */
/* Either X:[...] or \\server\[...] */
#define is_dos_path(s) (isdrive(s) \
|| ((s)[0] == '\\' \
&& (s)[1] == '\\' \
&& isalpha ((s)[2]) \
&& strchr ((s) + 3, '\\')))
static int __stdcall
globify (char *word, char **&argv, int &argc, int &argvlen)
{
if (*word != '~' && strpbrk (word, "?*[\"\'(){}") == NULL)
return 0;
int n = 0;
char *p, *s;
int dos_spec = is_dos_path (word);
if (!dos_spec && isquote (*word) && word[1] && word[2])
dos_spec = is_dos_path (word + 1);
/* We'll need more space if there are quoting characters in
word. If that is the case, doubling the size of the
string should provide more than enough space. */
if (strpbrk (word, "'\""))
n = strlen (word);
char pattern[strlen (word) + ((dos_spec + 1) * n) + 1];
/* Fill pattern with characters from word, quoting any
characters found within quotes. */
for (p = pattern, s = word; *s != '\000'; s++, p++)
if (!isquote (*s))
{
if (dos_spec && *s == '\\')
*p++ = '\\';
*p = *s;
}
else
{
char quote = *s;
while (*++s && *s != quote)
{
if (dos_spec || *s != '\\')
/* nothing */;
else if (s[1] == quote || s[1] == '\\')
s++;
*p++ = '\\';
size_t cnt = isascii (*s) ? 1 : mbtowc (NULL, s, MB_CUR_MAX);
if (cnt <= 1 || cnt == (size_t)-1)
*p++ = *s;
else
{
--s;
while (cnt-- > 0)
*p++ = *++s;
}
}
if (*s == quote)
p--;
if (*s == '\0')
break;
}
*p = '\0';
glob_t gl;
gl.gl_offs = 0;
/* Attempt to match the argument. Return just word (minus quoting) if no match. */
if (glob (pattern, GLOB_TILDE | GLOB_NOCHECK | GLOB_BRACE | GLOB_QUOTE, NULL, &gl) || !gl.gl_pathc)
return 0;
/* Allocate enough space in argv for the matched filenames. */
n = argc;
if ((argc += gl.gl_pathc) > argvlen)
{
argvlen = argc + 10;
argv = (char **) realloc (argv, (1 + argvlen) * sizeof (argv[0]));
}
/* Copy the matched filenames to argv. */
char **gv = gl.gl_pathv;
char **av = argv + n;
while (*gv)
{
debug_printf ("argv[%d] = '%s'", n++, *gv);
*av++ = *gv++;
}
/* Clean up after glob. */
free (gl.gl_pathv);
return 1;
}
/* Build argv, argc from string passed from Windows. */
static void __stdcall
build_argv (char *cmd, char **&argv, int &argc, int winshell)
{
int argvlen = 0;
int nesting = 0; // monitor "nesting" from insert_file
argc = 0;
argvlen = 0;
argv = NULL;
/* Scan command line until there is nothing left. */
while (*cmd)
{
/* Ignore spaces */
if (issep (*cmd))
{
cmd++;
continue;
}
/* Found the beginning of an argument. */
char *word = cmd;
char *sawquote = NULL;
while (*cmd)
{
if (*cmd != '"' && (!winshell || *cmd != '\''))
cmd++; // Skip over this character
else
/* Skip over characters until the closing quote */
{
sawquote = cmd;
/* Handle quoting. Only strip off quotes if the parent is
a Cygwin process, or if the word starts with a '@'.
In this case, the insert_file function needs an unquoted
DOS filename and globbing isn't performed anyway. */
cmd = quoted (cmd, winshell && argc > 0 && *word != '@');
}
if (issep (*cmd)) // End of argument if space
break;
}
if (*cmd)
*cmd++ = '\0'; // Terminate `word'
/* Possibly look for @file construction assuming that this isn't
the very first argument and the @ wasn't quoted */
if (argc && sawquote != word && *word == '@')
{
if (++nesting > MAX_AT_FILE_LEVEL)
api_fatal ("Too many levels of nesting for %s", word);
if (insert_file (word, cmd))
continue; // There's new stuff in cmd now
}
/* See if we need to allocate more space for argv */
if (argc >= argvlen)
{
argvlen = argc + 10;
argv = (char **) realloc (argv, (1 + argvlen) * sizeof (argv[0]));
}
/* Add word to argv file after (optional) wildcard expansion. */
if (!winshell || !argc || !globify (word, argv, argc, argvlen))
{
debug_printf ("argv[%d] = '%s'", argc, word);
argv[argc++] = word;
}
}
if (argv)
argv[argc] = NULL;
debug_printf ("argc %d", argc);
}
/* sanity and sync check */
void __stdcall
check_sanity_and_sync (per_process *p)
{
/* Sanity check to make sure developers didn't change the per_process */
/* struct without updating SIZEOF_PER_PROCESS [it makes them think twice */
/* about changing it]. */
if (sizeof (per_process) != SIZEOF_PER_PROCESS)
api_fatal ("per_process sanity check failed");
/* Make sure that the app and the dll are in sync. */
/* Complain if older than last incompatible change */
if (p->dll_major < CYGWIN_VERSION_DLL_EPOCH)
api_fatal ("cygwin DLL and APP are out of sync -- DLL version mismatch %u < %u",
p->dll_major, CYGWIN_VERSION_DLL_EPOCH);
/* magic_biscuit != 0 if using the old style version numbering scheme. */
if (p->magic_biscuit != SIZEOF_PER_PROCESS)
api_fatal ("Incompatible cygwin .dll -- incompatible per_process info %u != %u",
p->magic_biscuit, SIZEOF_PER_PROCESS);
/* Complain if incompatible API changes made */
if (p->api_major > cygwin_version.api_major)
api_fatal ("cygwin DLL and APP are out of sync -- API version mismatch %u > %u",
p->api_major, cygwin_version.api_major);
#ifndef __x86_64__
/* This is a kludge to work around a version of _cygwin_common_crt0
which overwrote the cxx_malloc field with the local DLL copy.
Hilarity ensues if the DLL is not loaded while the process
is forking. */
__cygwin_user_data.cxx_malloc = &default_cygwin_cxx_malloc;
#endif
}
child_info NO_COPY *child_proc_info;
#define CYGWIN_GUARD (PAGE_READWRITE | PAGE_GUARD)
void
child_info_fork::alloc_stack_hard_way (volatile char *b)
{
void *stack_ptr;
SIZE_T stacksize;
/* First check if the requested stack area is part of the user heap
or part of a mmapped region. If so, we have been started from a
pthread with an application-provided stack, and the stack has just
to be used as is. */
if ((stacktop >= cygheap->user_heap.base
&& stackbottom <= cygheap->user_heap.max)
|| is_mmapped_region ((caddr_t) stacktop, (caddr_t) stackbottom))
return;
/* First, try to reserve the entire stack. */
stacksize = (SIZE_T) stackbottom - (SIZE_T) stackaddr;
if (!VirtualAlloc (stackaddr, stacksize, MEM_RESERVE, PAGE_NOACCESS))
{
PTEB teb = NtCurrentTeb ();
api_fatal ("fork: can't reserve memory for parent stack "
"%p - %p, (child has %p - %p), %E",
stackaddr, stackbottom, teb->DeallocationStack, _tlsbase);
}
stacksize = (SIZE_T) stackbottom - (SIZE_T) stacktop;
stack_ptr = VirtualAlloc (stacktop, stacksize, MEM_COMMIT, PAGE_READWRITE);
if (!stack_ptr)
abort ("can't commit memory for stack %p(%ly), %E", stacktop, stacksize);
if (guardsize != (size_t) -1)
{
/* Allocate PAGE_GUARD page if it still fits. */
if (stack_ptr > stackaddr)
{
stack_ptr = (void *) ((LPBYTE) stack_ptr
- wincap.page_size ());
if (!VirtualAlloc (stack_ptr, wincap.page_size (), MEM_COMMIT,
CYGWIN_GUARD))
api_fatal ("fork: couldn't allocate new stack guard page %p, %E",
stack_ptr);
}
/* Allocate POSIX guard pages. */
if (guardsize > 0)
VirtualAlloc (stackaddr, guardsize, MEM_COMMIT, PAGE_NOACCESS);
}
b[0] = '\0';
}
void *getstack (void *) __attribute__ ((noinline));
volatile char *
getstack (volatile char * volatile p)
{
*p ^= 1;
*p ^= 1;
return p - 4096;
}
/* extend the stack prior to fork longjmp */
void
child_info_fork::alloc_stack ()
{
volatile char * volatile stackp;
#ifdef __x86_64__
__asm__ volatile ("movq %%rsp,%0": "=r" (stackp));
#else
__asm__ volatile ("movl %%esp,%0": "=r" (stackp));
#endif
/* Make sure not to try a hard allocation if we have been forked off from
the main thread of a Cygwin process which has been started from a 64 bit
parent. In that case the _tlsbase of the forked child is not the same
as the _tlsbase of the parent (== stackbottom), but only because the
stack of the parent has been slightly rearranged. See comment in
wow64_revert_to_original_stack for details. We check here if the
parent stack fits into the child stack. */
if (_tlsbase != stackbottom
&& (!wincap.is_wow64 ()
|| stacktop < (char *) NtCurrentTeb ()->DeallocationStack
|| stackbottom > _tlsbase))
alloc_stack_hard_way (stackp);
else
{
char *st = (char *) stacktop;
while (_tlstop > st)
stackp = getstack (stackp);
stackaddr = 0;
/* This only affects forked children of a process started from a native
64 bit process, but it doesn't hurt to do it unconditionally. Fix
StackBase in the child to be the same as in the parent, so that the
computation of _my_tls is correct. */
_tlsbase = (PVOID) stackbottom;
}
}
extern "C" void
break_here ()
{
static int NO_COPY sent_break;
if (!sent_break++)
DebugBreak ();
debug_printf ("break here");
}
static void
initial_env ()
{
if (GetEnvironmentVariableA ("CYGWIN_TESTING", NULL, 0))
_cygwin_testing = 1;
#ifdef DEBUGGING
char buf[NT_MAX_PATH];
if (GetEnvironmentVariableA ("CYGWIN_DEBUG", buf, sizeof (buf) - 1))
{
char buf1[NT_MAX_PATH];
GetModuleFileName (NULL, buf1, NT_MAX_PATH);
char *p = strpbrk (buf, ":=");
if (!p)
p = (char *) "gdb.exe -nw";
else
*p++ = '\0';
if (strcasestr (buf1, buf))
{
error_start_init (p);
jit_debug = true;
try_to_debug ();
console_printf ("*** Sending Break. gdb may issue spurious SIGTRAP message.\n");
break_here ();
}
}
#endif
}
child_info *
get_cygwin_startup_info ()
{
STARTUPINFO si;
GetStartupInfo (&si);
child_info *res = (child_info *) si.lpReserved2;
if (si.cbReserved2 < EXEC_MAGIC_SIZE || !res
|| res->intro != PROC_MAGIC_GENERIC || res->magic != CHILD_INFO_MAGIC)
{
strace.activate (false);
res = NULL;
}
else
{
if ((res->intro & OPROC_MAGIC_MASK) == OPROC_MAGIC_GENERIC)
multiple_cygwin_problem ("proc intro", res->intro, 0);
else if (res->cygheap != (void *) &_cygheap_start)
multiple_cygwin_problem ("cygheap base", (uintptr_t) res->cygheap,
(uintptr_t) &_cygheap_start);
unsigned should_be_cb = 0;
switch (res->type)
{
case _CH_FORK:
in_forkee = true;
should_be_cb = sizeof (child_info_fork);
/* fall through */;
case _CH_SPAWN:
case _CH_EXEC:
if (!should_be_cb)
should_be_cb = sizeof (child_info_spawn);
if (should_be_cb != res->cb)
multiple_cygwin_problem ("proc size", res->cb, should_be_cb);
else if (sizeof (fhandler_union) != res->fhandler_union_cb)
multiple_cygwin_problem ("fhandler size", res->fhandler_union_cb,
sizeof (fhandler_union));
if (res->isstraced ())
{
while (!being_debugged ())
yield ();
strace.activate (res->type == _CH_FORK);
}
break;
default:
system_printf ("unknown exec type %u", res->type);
/* intentionally fall through */
case _CH_WHOOPS:
res = NULL;
break;
}
}
return res;
}
#ifdef __x86_64__
#define dll_data_start &__data_start__
#define dll_data_end &__data_end__
#define dll_bss_start &__bss_start__
#define dll_bss_end &__bss_end__
#else
#define dll_data_start &_data_start__
#define dll_data_end &_data_end__
#define dll_bss_start &_bss_start__
#define dll_bss_end &_bss_end__
#endif
void
child_info_fork::handle_fork ()
{
cygheap_fixup_in_child (false);
memory_init ();
myself.thisproc (NULL);
myself->uid = cygheap->user.real_uid;
myself->gid = cygheap->user.real_gid;
child_copy (parent, false,
"dll data", dll_data_start, dll_data_end,
"dll bss", dll_bss_start, dll_bss_end,
"user heap", cygheap->user_heap.base, cygheap->user_heap.ptr,
NULL);
/* If my_wr_proc_pipe != NULL then it's a leftover handle from a previously
forked process. Close it now or suffer confusion with the parent of our
parent. */
if (my_wr_proc_pipe)
ForceCloseHandle1 (my_wr_proc_pipe, wr_proc_pipe);
/* Setup our write end of the process pipe. Clear the one in the structure.
The destructor should never be called for this but, it can't hurt to be
safe. */
my_wr_proc_pipe = wr_proc_pipe;
rd_proc_pipe = wr_proc_pipe = NULL;
/* Do the relocations here. These will actually likely be overwritten by the
below child_copy but we do them here in case there is a read-only section
which does not get copied by fork. */
_pei386_runtime_relocator (user_data);
/* step 2 now that the dll has its heap filled in, we can fill in the
user's data and bss since user_data is now filled out. */
child_copy (parent, false,
"data", user_data->data_start, user_data->data_end,
"bss", user_data->bss_start, user_data->bss_end,
NULL);
if (fixup_mmaps_after_fork (parent))
api_fatal ("recreate_mmaps_after_fork_failed");
}
bool
child_info_spawn::get_parent_handle ()
{
parent = OpenProcess (PROCESS_VM_READ, false, parent_winpid);
moreinfo->myself_pinfo = NULL;
return !!parent;
}
void
child_info_spawn::handle_spawn ()
{
extern void fixup_lockf_after_exec (bool);
HANDLE h;
if (!dynamically_loaded || get_parent_handle ())
{
cygheap_fixup_in_child (true);
memory_init ();
}
if (!moreinfo->myself_pinfo ||
!DuplicateHandle (GetCurrentProcess (), moreinfo->myself_pinfo,
GetCurrentProcess (), &h, 0,
FALSE, DUPLICATE_SAME_ACCESS | DUPLICATE_CLOSE_SOURCE))
h = NULL;
/* Setup our write end of the process pipe. Clear the one in the structure.
The destructor should never be called for this but, it can't hurt to be
safe. */
my_wr_proc_pipe = wr_proc_pipe;
rd_proc_pipe = wr_proc_pipe = NULL;
myself.thisproc (h);
__argc = moreinfo->argc;
__argv = moreinfo->argv;
envp = moreinfo->envp;
envc = moreinfo->envc;
if (!dynamically_loaded)
cygheap->fdtab.fixup_after_exec ();
if (__stdin >= 0)
cygheap->fdtab.move_fd (__stdin, 0);
if (__stdout >= 0)
cygheap->fdtab.move_fd (__stdout, 1);
cygheap->user.groups.clear_supp ();
/* If we're execing we may have "inherited" a list of children forked by the
previous process executing under this pid. Reattach them here so that we
can wait for them. */
if (type == _CH_EXEC)
reattach_children ();
ready (true);
/* Keep pointer to parent open if we've execed so that pid will not be reused.
Otherwise, we no longer need this handle so close it.
Need to do this after debug_fixup_after_fork_exec or DEBUGGING handling of
handles might get confused. */
if (type != _CH_EXEC && child_proc_info->parent)
{
CloseHandle (child_proc_info->parent);
child_proc_info->parent = NULL;
}
signal_fixup_after_exec ();
fixup_lockf_after_exec (type == _CH_EXEC);
}
/* Retrieve and store system directory for later use. Note that the
directory is stored with a trailing backslash! */
static void
init_windows_system_directory ()
{
if (!windows_system_directory_length)
{
windows_system_directory_length =
GetSystemDirectoryW (windows_system_directory, MAX_PATH);
if (windows_system_directory_length == 0)
api_fatal ("can't find windows system directory");
windows_system_directory[windows_system_directory_length++] = L'\\';
windows_system_directory[windows_system_directory_length] = L'\0';
#ifndef __x86_64__
system_wow64_directory_length =
GetSystemWow64DirectoryW (system_wow64_directory, MAX_PATH);
if (system_wow64_directory_length)
{
system_wow64_directory[system_wow64_directory_length++] = L'\\';
system_wow64_directory[system_wow64_directory_length] = L'\0';
}
#endif /* !__x86_64__ */
}
}
void
dll_crt0_0 ()
{
wincap.init ();
child_proc_info = get_cygwin_startup_info ();
init_windows_system_directory ();
initial_env ();
SetErrorMode (SEM_FAILCRITICALERRORS | SEM_NOGPFAULTERRORBOX);
lock_process::init ();
_impure_ptr = _GLOBAL_REENT;
_impure_ptr->_stdin = &_impure_ptr->__sf[0];
_impure_ptr->_stdout = &_impure_ptr->__sf[1];
_impure_ptr->_stderr = &_impure_ptr->__sf[2];
_impure_ptr->_current_locale = "C";
user_data->impure_ptr = _impure_ptr;
user_data->impure_ptr_ptr = &_impure_ptr;
DuplicateHandle (GetCurrentProcess (), GetCurrentThread (),
GetCurrentProcess (), &hMainThread,
0, false, DUPLICATE_SAME_ACCESS);
NtOpenProcessToken (NtCurrentProcess (), MAXIMUM_ALLOWED, &hProcToken);
set_cygwin_privileges (hProcToken);
device::init ();
do_global_ctors (&__CTOR_LIST__, 1);
cygthread::init ();
if (!child_proc_info)
{
setup_cygheap ();
memory_init ();
#ifndef __x86_64__
/* WOW64 process on XP/64 or Server 2003/64? Check if we have been
started from 64 bit process and if our stack is at an unusual
address. Set wow64_needs_stack_adjustment if so. Problem
description in wow64_test_for_64bit_parent. */
if (wincap.wow64_has_secondary_stack ())
wow64_needs_stack_adjustment = wow64_test_for_64bit_parent ();
#endif /* !__x86_64__ */
}
else
{
cygwin_user_h = child_proc_info->user_h;
switch (child_proc_info->type)
{
case _CH_FORK:
fork_info->handle_fork ();
break;
case _CH_SPAWN:
case _CH_EXEC:
spawn_info->handle_spawn ();
break;
}
}
user_data->threadinterface->Init ();
_main_tls = &_my_tls;
/* Initialize signal processing here, early, in the hopes that the creation
of a thread early in the process will cause more predictability in memory
layout for the main thread. */
if (!dynamically_loaded)
sigproc_init ();
debug_printf ("finished dll_crt0_0 initialization");
}
static inline void
main_thread_sinit ()
{
__sinit (_impure_ptr);
/* At this point, _impure_ptr == _global_impure_ptr == _GLOBAL_REENT is
initialized, but _REENT == _my_tls.local_clib doesn't know about it.
It has been copied over from _GLOBAL_REENT in _cygtls::init_thread
*before* the initialization took place.
As soon as the main thread calls a stdio function, this would be
rectified. But if another thread calls a stdio function on
stdin/out/err before the main thread does, all the required
initialization of stdin/out/err will be done, but _REENT->__sdidinit
is *still* 0. This in turn will result in a call to __sinit in the
wrong spot. The input or output buffer will be NULLed and nothing is
read or written in the first stdio function call in the main thread.
To fix this issue we have to copy over the relevant part of _GLOBAL_REENT
to _REENT here again. */
_REENT->__sdidinit = -1;
_REENT->__cleanup = _GLOBAL_REENT->__cleanup;
}
/* Take over from libc's crt0.o and start the application. Note the
various special cases when Cygwin DLL is being runtime loaded (as
opposed to being link-time loaded by Cygwin apps) from a non
cygwin app via LoadLibrary. */
void
dll_crt0_1 (void *)
{
extern void initial_setlocale ();
_my_tls.incyg++;
/* Inherit "parent" exec'ed process sigmask */
if (spawn_info && !in_forkee)
_my_tls.sigmask = spawn_info->moreinfo->sigmask;
if (dynamically_loaded)
sigproc_init ();
check_sanity_and_sync (user_data);
/* Initialize malloc and then call user_shared_initialize since it relies
on a functioning malloc and it's possible that the user's program may
have overridden malloc. We only know about that at this stage,
unfortunately. */
malloc_init ();
user_shared->initialize ();
#ifdef CYGHEAP_DEBUG
int i = 0;
const int n = 2 * 1024 * 1024;
while (i--)
{
void *p = cmalloc (HEAP_STR, n);
if (p)
small_printf ("cmalloc returns %p\n", cmalloc (HEAP_STR, n));
else
{
small_printf ("total allocated %y\n", (i - 1) * n);
break;
}
}
#endif
ProtectHandle (hMainThread);
cygheap->cwd.init ();
/* Initialize pthread mainthread when not forked and it is safe to call new,
otherwise it is reinitalized in fixup_after_fork */
if (!in_forkee)
{
pthread::init_mainthread ();
_pei386_runtime_relocator (user_data);
}
#ifdef DEBUGGING
strace.microseconds ();
#endif
/* Initialize debug muto, if DLL is built with --enable-debugging.
Need to do this before any helper threads start. */
debug_init ();
#ifdef NEWVFORK
cygheap->fdtab.vfork_child_fixup ();
main_vfork = vfork_storage.create ();
#endif
cygbench ("pre-forkee");
if (in_forkee)
{
/* If we've played with the stack, stacksize != 0. That means that
fork() was invoked from other than the main thread. Make sure that
frame pointer is referencing the new stack so that the OS knows what
to do when it needs to increase the size of the stack.
NOTE: Don't do anything that involves the stack until you've completed
this step. */
if (fork_info->stackaddr)
{
_tlsbase = (PVOID) fork_info->stackbottom;
_tlstop = (PVOID) fork_info->stacktop;
}
/* Not resetting _my_tls.incyg here because presumably fork will overwrite
it with the value of the forker and all will be good. */
longjmp (fork_info->jmp, true);
}
main_thread_sinit ();
#ifdef DEBUGGING
{
extern void fork_init ();
fork_init ();
}
#endif
pinfo_init (envp, envc);
strace.dll_info ();
/* Allocate cygheap->fdtab */
dtable_init ();
/* Set internal locale to the environment settings. */
initial_setlocale ();
uinfo_init (); /* initialize user info */
/* Connect to tty. */
tty::init_session ();
if (!__argc)
{
PWCHAR wline = GetCommandLineW ();
size_t size = sys_wcstombs (NULL, 0, wline);
char *line = (char *) alloca (size);
sys_wcstombs (line, size, wline);
/* Scan the command line and build argv. Expand wildcards if not
called from another cygwin process. */
build_argv (line, __argv, __argc,
NOTSTATE (myself, PID_CYGPARENT) && allow_glob);
/* Convert argv[0] to posix rules if it's currently blatantly
win32 style. */
if ((strchr (__argv[0], ':')) || (strchr (__argv[0], '\\')))
{
char *new_argv0 = (char *) malloc (NT_MAX_PATH);
cygwin_conv_path (CCP_WIN_A_TO_POSIX | CCP_RELATIVE, __argv[0],
new_argv0, NT_MAX_PATH);
__argv[0] = (char *) realloc (new_argv0, strlen (new_argv0) + 1);
}
}
__argc_safe = __argc;
if (user_data->premain[0])
for (unsigned int i = 0; i < PREMAIN_LEN / 2; i++)
user_data->premain[i] (__argc, __argv, user_data);
/* Set up standard fds in file descriptor table. */
cygheap->fdtab.stdio_init ();
/* Set up __progname for getopt error call. */
if (__argv[0] && (__progname = strrchr (__argv[0], '/')))
++__progname;
else
__progname = __argv[0];
program_invocation_name = __argv[0];
program_invocation_short_name = __progname;
if (__progname)
{
char *cp = strchr (__progname, '\0') - 4;
if (cp > __progname && ascii_strcasematch (cp, ".exe"))
*cp = '\0';
}
(void) xdr_set_vprintf (&cygxdr_vwarnx);
cygwin_finished_initializing = true;
/* Call init of loaded dlls. */
dlls.init ();
/* Execute any specified "premain" functions */
if (user_data->premain[PREMAIN_LEN / 2])
for (unsigned int i = PREMAIN_LEN / 2; i < PREMAIN_LEN; i++)
user_data->premain[i] (__argc, __argv, user_data);
set_errno (0);
if (dynamically_loaded)
{
_setlocale_r (_REENT, LC_CTYPE, "C");
return;
}
/* Disable case-insensitive globbing */
ignore_case_with_glob = false;
MALLOC_CHECK;
cygbench (__progname);
ld_preload ();
/* Per POSIX set the default application locale back to "C". */
_setlocale_r (_REENT, LC_CTYPE, "C");
if (!user_data->main)
{
/* Handle any signals which may have arrived */
_my_tls.call_signal_handler ();
_my_tls.incyg--; /* Not in Cygwin anymore */
}
else
{
/* Create a copy of Cygwin's version of __argv so that, if the user makes
a change to an element of argv[] it does not affect Cygwin's argv.
Changing the the contents of what argv[n] points to will still
affect Cygwin. This is similar (but not exactly like) Linux. */
char *newargv[__argc + 1];
char **nav = newargv;
char **oav = __argv;
while ((*nav++ = *oav++) != NULL)
continue;
/* Handle any signals which may have arrived */
sig_dispatch_pending (false);
_my_tls.call_signal_handler ();
_my_tls.incyg--; /* Not in Cygwin anymore */
#ifdef __x86_64__
cygwin_exit (user_data->main (__argc, newargv, __cygwin_environ));
#else
cygwin_exit (user_data->main (__argc, newargv, *user_data->envptr));
#endif
}
__asm__ (" \n\
.global _cygwin_exit_return \n\
.global __cygwin_exit_return \n\
_cygwin_exit_return: \n\
__cygwin_exit_return: \n\
nop \n\
");
}
extern "C" void __stdcall
_dll_crt0 ()
{
#ifndef __x86_64__
/* Handle WOW64 process on XP/2K3 which has been started from native 64 bit
process. See comment in wow64_test_for_64bit_parent for a full problem
description. */
if (wow64_needs_stack_adjustment && !dynamically_loaded)
{
/* Must be static since it's referenced after the stack and frame
pointer registers have been changed. */
static PVOID allocationbase = 0;
/* Check if we just move the stack. If so, wow64_revert_to_original_stack
returns a non-NULL, 16 byte aligned address. See comments in
wow64_revert_to_original_stack for the gory details. */
PVOID stackaddr = wow64_revert_to_original_stack (allocationbase);
if (stackaddr)
{
/* 2nd half of the stack move. Set stack pointer to new address.
Set frame pointer to 0. */
__asm__ ("\n\
movl %[ADDR], %%esp \n\
xorl %%ebp, %%ebp \n"
: : [ADDR] "r" (stackaddr));
/* Now we're back on the original stack. Free up space taken by the
former main thread stack and set DeallocationStack correctly. */
VirtualFree (NtCurrentTeb ()->DeallocationStack, 0, MEM_RELEASE);
NtCurrentTeb ()->DeallocationStack = allocationbase;
}
else
/* Fall back to respawn if wow64_revert_to_original_stack fails. */
wow64_respawn_process ();
}
#endif /* !__x86_64__ */
_feinitialise ();
#ifndef __x86_64__
main_environ = user_data->envptr;
#endif
if (in_forkee)
{
fork_info->alloc_stack ();
_main_tls = &_my_tls;
}
_main_tls->call ((DWORD (*) (void *, void *)) dll_crt0_1, NULL);
}
void
dll_crt0 (per_process *uptr)
{
/* Set the local copy of the pointer into the user space. */
if (!in_forkee && uptr && uptr != user_data)
{
memcpy (user_data, uptr, per_process_overwrite);
*(user_data->impure_ptr_ptr) = _GLOBAL_REENT;
}
_dll_crt0 ();
}
/* This must be called by anyone who uses LoadLibrary to load cygwin1.dll.
You must have CYGTLS_PADSIZE bytes reserved at the bottom of the stack
calling this function, and that storage must not be overwritten until you
unload cygwin1.dll, as it is used for _my_tls. It is best to load
cygwin1.dll before spawning any additional threads in your process.
See winsup/testsuite/cygload for an example of how to use cygwin1.dll
from MSVC and non-cygwin MinGW applications. */
extern "C" void
cygwin_dll_init ()
{
#ifndef __x86_64__
static char **envp;
#endif
static int _fmode;
user_data->magic_biscuit = sizeof (per_process);
#ifndef __x86_64__
user_data->envptr = &envp;
#endif
user_data->fmode_ptr = &_fmode;
_dll_crt0 ();
}
extern "C" void
__main (void)
{
/* Ordering is critical here. DLL ctors have already been
run as they were being loaded, so we should stack the
queued call to DLL dtors now. */
atexit (dll_global_dtors);
do_global_ctors (user_data->ctors, false);
/* Now we have run global ctors, register their dtors.
At exit, global dtors will run first, so the app can still
use shared library functions while terminating; then the
DLLs will be destroyed; finally newlib will shut down stdio
and terminate itself. */
atexit (do_global_dtors);
sig_dispatch_pending (true);
}
void __reg1
do_exit (int status)
{
syscall_printf ("do_exit (%d), exit_state %d", status, exit_state);
#ifdef NEWVFORK
vfork_save *vf = vfork_storage.val ();
if (vf != NULL && vf->pid < 0)
{
exit_state = ES_NOT_EXITING;
vf->restore_exit (status);
}
#endif
lock_process until_exit (true);
if (exit_state < ES_EVENTS_TERMINATE)
exit_state = ES_EVENTS_TERMINATE;
if (exit_state < ES_SIGNAL)
{
exit_state = ES_SIGNAL;
signal (SIGCHLD, SIG_IGN);
signal (SIGHUP, SIG_IGN);
signal (SIGINT, SIG_IGN);
signal (SIGQUIT, SIG_IGN);
}
if (exit_state < ES_CLOSEALL)
{
exit_state = ES_CLOSEALL;
close_all_files ();
}
UINT n = (UINT) status;
if (exit_state < ES_THREADTERM)
{
exit_state = ES_THREADTERM;
cygthread::terminate ();
}
myself->stopsig = 0;
if (exit_state < ES_HUP_PGRP)
{
exit_state = ES_HUP_PGRP;
/* Kill orphaned children on group leader exit */
if (myself->has_pgid_children && myself->pid == myself->pgid)
{
siginfo_t si = {0};
si.si_signo = -SIGHUP;
si.si_code = SI_KERNEL;
sigproc_printf ("%u == pgrp %u, send SIG{HUP,CONT} to stopped children",
myself->pid, myself->pgid);
kill_pgrp (myself->pgid, si);
}
}
if (exit_state < ES_HUP_SID)
{
exit_state = ES_HUP_SID;
/* Kill the foreground process group on session leader exit */
if (getpgrp () > 0 && myself->pid == myself->sid && real_tty_attached (myself))
{
tty *tp = cygwin_shared->tty[myself->ctty];
sigproc_printf ("%u == sid %u, send SIGHUP to children",
myself->pid, myself->sid);
/* CGF FIXME: This can't be right. */
if (tp->getsid () == myself->sid)
tp->kill_pgrp (SIGHUP);
}
}
myself.exit (n);
}
/* When introducing support for -fuse-cxa-atexit with Cygwin 1.7.32 and
GCC 4.8.3-3, we defined __dso_value as &ImageBase. This supposedly allowed
a reproducible value which could also be easily evaluated in cygwin_atexit.
However, when building C++ applications with -fuse-cxa-atexit, G++ creates
calls to __cxa_atexit using the *address* of __dso_handle as DSO handle.
So what we do here is this: A call to __cxa_atexit from the application
actually calls cygwin__cxa_atexit. From dso_handle (which is either
&__dso_handle, or __dso_handle == ImageBase or NULL) we fetch the dll
structure of the DLL. Then use dll::handle == ImageBase as the actual DSO
handle value in calls to __cxa_atexit and __cxa_finalize.
Thus, __cxa_atexit becomes entirely independent of the incoming value of
dso_handle, as long as it's *some* pointer into the DSO's address space. */
extern "C" int
cygwin__cxa_atexit (void (*fn)(void *), void *obj, void *dso_handle)
{
dll *d = dso_handle ? dlls.find (dso_handle) : NULL;
return __cxa_atexit (fn, obj, d ? d->handle : NULL);
}
/* This function is only called for applications built with Cygwin versions
up to API 0.279. Starting with API 0.280 (Cygwin 1.7.33/1.8.6-2), atexit
is a statically linked function inside of libcygwin.a. The reason is that
the old method to fetch the caller return address is unreliable given GCCs
ability to perform tail call elimination. For the details, see the below
comment. The atexit replacement is defined in libcygwin.a to allow reliable
access to the correct DSO handle. */
extern "C" int
cygwin_atexit (void (*fn) (void))
{
int res;
dll *d = dlls.find ((void *) _my_tls.retaddr ());
#ifdef __x86_64__
/* x86_64 DLLs created with GCC 4.8.3-3 register __gcc_deregister_frame
as atexit function using a call to atexit, rather than __cxa_atexit.
Due to GCC's tail call optimizing, cygwin_atexit doesn't get the correct
return address on the stack. As a result it fails to get the HMODULE of
the caller and thus calls atexit rather than __cxa_atexit. Then, if the
module gets dlclosed, __cxa_finalize (called from dll_list::detach) can't
remove __gcc_deregister_frame from the atexit function chain. So at
process exit, __call_exitprocs calls __gcc_deregister_frame while the
module is already unloaded and the __gcc_deregister_frame function not
available ==> SEGV.
This also occurs for other functions.
Workaround: If dlls.find fails, try to find the dll entry of the DLL
containing fn. If that works, proceed by calling __cxa_atexit, otherwise
call atexit.
This *should* be sufficiently safe. Ultimately, new applications will
use the statically linked atexit function though, as outlined above. */
if (!d)
d = dlls.find ((void *) fn);
#endif
res = d ? __cxa_atexit ((void (*) (void *)) fn, NULL, d->handle) : atexit (fn);
return res;
}
extern "C" void
cygwin_exit (int n)
{
exit_state = ES_EXIT_STARTING;
exit (n);
}
extern "C" void
_exit (int n)
{
do_exit (((DWORD) n & 0xff) << 8);
}
extern "C" void cygwin_stackdump ();
extern "C" void
vapi_fatal (const char *fmt, va_list ap)
{
char buf[4096];
int n = __small_sprintf (buf, "%P: *** fatal error %s- ", in_forkee ? "in forked process " : "");
__small_vsprintf (buf + n, fmt, ap);
va_end (ap);
strace.prntf (_STRACE_SYSTEM, NULL, "%s", buf);
#ifdef DEBUGGING
try_to_debug ();
#endif
cygwin_stackdump ();
myself.exit (__api_fatal_exit_val);
}
extern "C" void
api_fatal (const char *fmt, ...)
{
va_list ap;
va_start (ap, fmt);
vapi_fatal (fmt, ap);
}
void
multiple_cygwin_problem (const char *what, uintptr_t magic_version, uintptr_t version)
{
if (_cygwin_testing && (strstr (what, "proc") || strstr (what, "cygheap")))
{
child_proc_info->type = _CH_WHOOPS;
return;
}
if (GetEnvironmentVariableA ("CYGWIN_MISMATCH_OK", NULL, 0))
return;
if (CYGWIN_VERSION_MAGIC_VERSION (magic_version) == version)
system_printf ("%s magic number mismatch detected - %p/%ly", what, magic_version, version);
else
api_fatal ("%s mismatch detected - %ly/%ly.\n\
This problem is probably due to using incompatible versions of the cygwin DLL.\n\
Search for cygwin1.dll using the Windows Start->Find/Search facility\n\
and delete all but the most recent version. The most recent version *should*\n\
reside in x:\\cygwin\\bin, where 'x' is the drive on which you have\n\
installed the cygwin distribution. Rebooting is also suggested if you\n\
are unable to find another cygwin DLL.",
what, magic_version, version);
}
#ifdef DEBUGGING
void __reg1
cygbench (const char *s)
{
if (GetEnvironmentVariableA ("CYGWIN_BENCH", NULL, 0))
small_printf ("%05u ***** %s : %10d\n", GetCurrentProcessId (), s, strace.microseconds ());
}
#endif