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[CRT] Update file descriptor handling to match Wine (7/7). CORE-14504

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Import Wine commits by Piotr Caban:
* 6ed69c107f8 msvcrt: Avoid using global critical section while allocating new file descriptors.
* 725e4733cf8 msvcrt: Remove no longer needed global lock from functions using fd critical sections.
This commit is contained in:
Thomas Faber 2018-03-25 18:23:18 +02:00
parent 27b79867ea
commit 6aa8e3cc20
No known key found for this signature in database
GPG key ID: 076E7C3D44720826
1 changed files with 47 additions and 105 deletions
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152
sdk/lib/crt/stdio/file.c
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@ -125,9 +125,6 @@ ioinfo * __pioinfo[MSVCRT_MAX_FILES/MSVCRT_FD_BLOCK_SIZE] = { 0 };
*/
ioinfo __badioinfo = { INVALID_HANDLE_VALUE, WX_TEXT };
static int fdstart = 3; /* first unallocated fd */
static int fdend = 3; /* highest allocated fd */
typedef struct {
FILE file;
CRITICAL_SECTION crit;
@ -143,12 +140,9 @@ static int MSVCRT_umask = 0;
/* INTERNAL: static data for tmpnam and _wtmpname functions */
static int tmpnam_unique;
/* This critical section protects the tables __pioinfo and fstreams,
* and their related indexes, fdstart, fdend,
* and MSVCRT_stream_idx, from race conditions.
* It doesn't protect against race conditions manipulating the underlying files
* or flags; doing so would probably be better accomplished with per-file
* protection, rather than locking the whole table for every change.
/* This critical section protects the MSVCRT_fstreams table
* and MSVCRT_stream_idx from race conditions. It also
* protects fd critical sections creation code.
*/
static CRITICAL_SECTION MSVCRT_file_cs;
static CRITICAL_SECTION_DEBUG MSVCRT_file_cs_debug =
@ -172,19 +166,24 @@ static inline ioinfo* get_ioinfo_nolock(int fd)
return ret + (fd%MSVCRT_FD_BLOCK_SIZE);
}
static inline void init_ioinfo_cs(ioinfo *info)
{
if(!(info->exflag & EF_CRIT_INIT)) {
LOCK_FILES();
if(!(info->exflag & EF_CRIT_INIT)) {
InitializeCriticalSection(&info->crit);
info->exflag |= EF_CRIT_INIT;
}
UNLOCK_FILES();
}
}
/*static*/ inline ioinfo* get_ioinfo(int fd)
{
ioinfo *ret = get_ioinfo_nolock(fd);
if(ret == &__badioinfo)
return ret;
if(!(ret->exflag & EF_CRIT_INIT)) {
LOCK_FILES();
if(!(ret->exflag & EF_CRIT_INIT)) {
InitializeCriticalSection(&ret->crit);
ret->exflag |= EF_CRIT_INIT;
}
UNLOCK_FILES();
}
init_ioinfo_cs(ret);
EnterCriticalSection(&ret->crit);
return ret;
}
@ -216,77 +215,49 @@ static inline BOOL alloc_pioinfo_block(int fd)
static inline ioinfo* get_ioinfo_alloc_fd(int fd)
{
ioinfo *ret, *info;
ioinfo *ret;
ret = get_ioinfo(fd);
if(ret != &__badioinfo)
{
LOCK_FILES();
/* locate next free slot */
if (fd == fdstart && fd == fdend)
fdstart = fdend + 1;
else if (fd == fdstart)
{
fdstart++;
while (fdstart < fdend &&
((info = get_ioinfo_nolock(fdstart))->exflag & EF_CRIT_INIT))
{
if (TryEnterCriticalSection(&info->crit))
{
if (info->handle == INVALID_HANDLE_VALUE)
{
LeaveCriticalSection(&info->crit);
break;
}
LeaveCriticalSection(&info->crit);
}
fdstart++;
}
}
/* update last fd in use */
if (fd >= fdend)
fdend = fd + 1;
TRACE("fdstart is %d, fdend is %d\n", fdstart, fdend);
UNLOCK_FILES();
return ret;
}
if(!alloc_pioinfo_block(fd))
return &__badioinfo;
ret = get_ioinfo(fd);
if(ret == &__badioinfo)
return ret;
return get_ioinfo(fd);
}
LOCK_FILES();
/* locate next free slot */
if (fd == fdstart && fd == fdend)
fdstart = fdend + 1;
else if (fd == fdstart)
static inline ioinfo* get_ioinfo_alloc(int *fd)
{
int i;
*fd = -1;
for(i=0; i<MSVCRT_MAX_FILES; i++)
{
fdstart++;
while (fdstart < fdend &&
((info = get_ioinfo_nolock(fdstart))->exflag & EF_CRIT_INIT))
ioinfo *info = get_ioinfo_nolock(i);
if(info == &__badioinfo)
{
if (TryEnterCriticalSection(&info->crit))
if(!alloc_pioinfo_block(i))
return &__badioinfo;
info = get_ioinfo_nolock(i);
}
init_ioinfo_cs(info);
if(TryEnterCriticalSection(&info->crit))
{
if(info->handle == INVALID_HANDLE_VALUE)
{
if (info->handle == INVALID_HANDLE_VALUE)
{
LeaveCriticalSection(&info->crit);
break;
}
LeaveCriticalSection(&info->crit);
*fd = i;
return info;
}
fdstart++;
LeaveCriticalSection(&info->crit);
}
}
/* update last fd in use */
if (fd >= fdend)
fdend = fd + 1;
TRACE("fdstart is %d, fdend is %d\n", fdstart, fdend);
UNLOCK_FILES();
return ret;
WARN(":files exhausted!\n");
*_errno() = ENFILE;
return &__badioinfo;
}
/*static*/ inline void release_ioinfo(ioinfo *info)
@ -349,13 +320,6 @@ static void msvcrt_free_fd(int fd)
}
}
release_ioinfo(fdinfo);
LOCK_FILES();
if (fd == fdend - 1)
fdend--;
if (fd < fdstart)
fdstart = fd;
UNLOCK_FILES();
}
static void msvcrt_set_fd(ioinfo *fdinfo, HANDLE hand, int flag)
@ -378,23 +342,11 @@ static void msvcrt_set_fd(ioinfo *fdinfo, HANDLE hand, int flag)
/* INTERNAL: Allocate an fd slot from a Win32 HANDLE */
/*static*/ int msvcrt_alloc_fd(HANDLE hand, int flag)
{
ioinfo *info;
int fd;
ioinfo *info = get_ioinfo_alloc(&fd);
LOCK_FILES();
fd = fdstart;
TRACE(":handle (%p) allocating fd (%d)\n", hand, fd);
if (fd >= MSVCRT_MAX_FILES)
{
UNLOCK_FILES();
WARN(":files exhausted!\n");
*_errno() = ENFILE;
return -1;
}
info = get_ioinfo_alloc_fd(fd);
UNLOCK_FILES();
if(info == &__badioinfo)
return -1;
@ -533,9 +485,6 @@ void msvcrt_init_io(void)
wxflag_ptr++; handle_ptr++;
}
fdend = max( 3, count );
for (fdstart = 3; fdstart < fdend; fdstart++)
if (get_ioinfo_nolock(fdstart)->handle == INVALID_HANDLE_VALUE) break;
}
fdinfo = get_ioinfo_alloc_fd(STDIN_FILENO);
@ -984,7 +933,6 @@ int CDECL _close(int fd)
ioinfo *info = get_ioinfo(fd);
int ret;
LOCK_FILES();
TRACE(":fd (%d) handle (%p)\n", fd, info->handle);
if (!(info->wxflag & WX_OPEN)) {
ret = -1;
@ -997,7 +945,6 @@ int CDECL _close(int fd)
ret = -1;
}
}
UNLOCK_FILES();
release_ioinfo(info);
return ret;
}
@ -1015,7 +962,6 @@ int CDECL _dup2(int od, int nd)
int ret;
TRACE("(od=%d, nd=%d)\n", od, nd);
LOCK_FILES();
if (od < nd)
{
@ -1062,7 +1008,6 @@ int CDECL _dup2(int od, int nd)
release_ioinfo(info_od);
release_ioinfo(info_nd);
UNLOCK_FILES();
return ret;
}
@ -1072,14 +1017,13 @@ int CDECL _dup2(int od, int nd)
int CDECL _dup(int od)
{
int fd, ret;
ioinfo *info = get_ioinfo_alloc(&fd);
LOCK_FILES();
fd = fdstart;
if (_dup2(od, fd) == 0)
ret = fd;
else
ret = -1;
UNLOCK_FILES();
release_ioinfo(info);
return ret;
}
@ -1767,7 +1711,6 @@ int CDECL _pipe(int *pfds, unsigned int psize, int textmode)
unsigned int wxflags = split_oflags(textmode);
int fd;
LOCK_FILES();
fd = msvcrt_alloc_fd(readHandle, wxflags);
if (fd != -1)
{
@ -1791,7 +1734,6 @@ int CDECL _pipe(int *pfds, unsigned int psize, int textmode)
CloseHandle(writeHandle);
*_errno() = EMFILE;
}
UNLOCK_FILES();
}
else
_dosmaperr(GetLastError());
@ -3468,7 +3410,7 @@ FILE* CDECL _wfreopen(const wchar_t *path, const wchar_t *mode, FILE* file)
TRACE(":path (%p) mode (%s) file (%p) fd (%d)\n", debugstr_w(path), debugstr_w(mode), file, file ? file->_file : -1);
LOCK_FILES();
if (!file || ((fd = file->_file) < 0) || fd > fdend)
if (!file || ((fd = file->_file) < 0))
file = NULL;
else
{