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Next stage of stdio cleanup: Retire __sFILEX and merge the fields bac…
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__sFILE.  This was supposed to be done in 6.0.  Some notes:
- Where possible I restored the various lines to their pre-__sFILEX state.
- Retire INITEXTRA() and just initialize the wchar bits (orientation and
  mbstate) explicitly instead.  The various places that used INITEXTRA
  didn't need the locking fields or _up initialized.  (Some places needed
  _up to exist and not be off the end of a NULL or garbage pointer, but
  they didn't require it to be initialized to a specific value.)
- For now, stdio.h "knows" that pthread_t is a 'struct pthread *' to
  avoid namespace pollution of including all the pthread types in stdio.h.
  Once we remove all the inlines and make __sFILE private it can go back
  to using pthread_t, etc.
- This does not remove any of the inlines currently and does not change
  any of the public ABI of 'FILE'.

MFC after:	1 month
Reviewed by:	peter
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bsdjhb committed Apr 17, 2008
1 parent aba7c5b commit 1e98f88
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Showing 27 changed files with 79 additions and 147 deletions.
11 changes: 7 additions & 4 deletions include/stdio.h
Original file line number Diff line number Diff line change
Expand Up @@ -72,9 +72,6 @@ struct __sbuf {
int _size;
};

/* hold a buncha junk that would grow the ABI */
struct __sFILEX;

/*
* stdio state variables.
*
Expand Down Expand Up @@ -121,7 +118,7 @@ typedef struct __sFILE {

/* separate buffer for long sequences of ungetc() */
struct __sbuf _ub; /* ungetc buffer */
struct __sFILEX *_extra; /* additions to FILE to not break ABI */
unsigned char *_up; /* saved _p when _p is doing ungetc data */
int _ur; /* saved _r when _r is counting ungetc data */

/* tricks to meet minimum requirements even when malloc() fails */
Expand All @@ -134,6 +131,12 @@ typedef struct __sFILE {
/* Unix stdio files get aligned to block boundaries on fseek() */
int _blksize; /* stat.st_blksize (may be != _bf._size) */
fpos_t _offset; /* current lseek offset */

struct pthread_mutex *_fl_mutex; /* used for MT-safety */
struct pthread *_fl_owner; /* current owner */
int _fl_count; /* recursive lock count */
int _orientation; /* orientation for fwide() */
__mbstate_t _mbstate; /* multibyte conversion state */
} FILE;

#ifndef _STDSTREAM_DECLARED
Expand Down
42 changes: 16 additions & 26 deletions lib/libc/stdio/_flock_stub.c
Original file line number Diff line number Diff line change
Expand Up @@ -55,31 +55,21 @@ __weak_reference(_flockfile_debug_stub, _flockfile_debug);
__weak_reference(_ftrylockfile, ftrylockfile);
__weak_reference(_funlockfile, funlockfile);

/*
* We need to retain binary compatibility for a while. So pretend
* that _lock is part of FILE * even though it is dereferenced off
* _extra now. When we stop encoding the size of FILE into binaries
* this can be changed in stdio.h. This will reduce the amount of
* code that has to change in the future (just remove this comment
* and #define).
*/
#define _lock _extra

void
_flockfile(FILE *fp)
{
pthread_t curthread = _pthread_self();

if (fp->_lock->fl_owner == curthread)
fp->_lock->fl_count++;
if (fp->_fl_owner == curthread)
fp->_fl_count++;
else {
/*
* Make sure this mutex is treated as a private
* internal mutex:
*/
_pthread_mutex_lock(&fp->_lock->fl_mutex);
fp->_lock->fl_owner = curthread;
fp->_lock->fl_count = 1;
_pthread_mutex_lock(&fp->_fl_mutex);
fp->_fl_owner = curthread;
fp->_fl_count = 1;
}
}

Expand All @@ -98,15 +88,15 @@ _ftrylockfile(FILE *fp)
pthread_t curthread = _pthread_self();
int ret = 0;

if (fp->_lock->fl_owner == curthread)
fp->_lock->fl_count++;
if (fp->_fl_owner == curthread)
fp->_fl_count++;
/*
* Make sure this mutex is treated as a private
* internal mutex:
*/
else if (_pthread_mutex_trylock(&fp->_lock->fl_mutex) == 0) {
fp->_lock->fl_owner = curthread;
fp->_lock->fl_count = 1;
else if (_pthread_mutex_trylock(&fp->_fl_mutex) == 0) {
fp->_fl_owner = curthread;
fp->_fl_count = 1;
}
else
ret = -1;
Expand All @@ -121,26 +111,26 @@ _funlockfile(FILE *fp)
/*
* Check if this file is owned by the current thread:
*/
if (fp->_lock->fl_owner == curthread) {
if (fp->_fl_owner == curthread) {
/*
* Check if this thread has locked the FILE
* more than once:
*/
if (fp->_lock->fl_count > 1)
if (fp->_fl_count > 1)
/*
* Decrement the count of the number of
* times the running thread has locked this
* file:
*/
fp->_lock->fl_count--;
fp->_fl_count--;
else {
/*
* The running thread will release the
* lock now:
*/
fp->_lock->fl_count = 0;
fp->_lock->fl_owner = NULL;
_pthread_mutex_unlock(&fp->_lock->fl_mutex);
fp->_fl_count = 0;
fp->_fl_owner = NULL;
_pthread_mutex_unlock(&fp->_fl_mutex);
}
}
}
5 changes: 2 additions & 3 deletions lib/libc/stdio/asprintf.c
Original file line number Diff line number Diff line change
Expand Up @@ -43,7 +43,6 @@ asprintf(char **str, char const *fmt, ...)
int ret;
va_list ap;
FILE f;
struct __sFILEX ext;

f._file = -1;
f._flags = __SWR | __SSTR | __SALC;
Expand All @@ -54,8 +53,8 @@ asprintf(char **str, char const *fmt, ...)
return (-1);
}
f._bf._size = f._w = 127; /* Leave room for the NUL */
f._extra = &ext;
INITEXTRA(&f);
f._orientation = 0;
memset(&f._mbstate, 0, sizeof(mbstate_t));
va_start(ap, fmt);
ret = __vfprintf(&f, fmt, ap); /* Use unlocked __vfprintf */
va_end(ap);
Expand Down
2 changes: 1 addition & 1 deletion lib/libc/stdio/fgetwc.c
Original file line number Diff line number Diff line change
Expand Up @@ -71,7 +71,7 @@ __fgetwc(FILE *fp)
return (wc);
}
do {
nconv = __mbrtowc(&wc, fp->_p, fp->_r, &fp->_extra->mbstate);
nconv = __mbrtowc(&wc, fp->_p, fp->_r, &fp->_mbstate);
if (nconv == (size_t)-1)
break;
else if (nconv == (size_t)-2)
Expand Down
4 changes: 2 additions & 2 deletions lib/libc/stdio/fgetws.c
Original file line number Diff line number Diff line change
Expand Up @@ -62,7 +62,7 @@ fgetws(wchar_t * __restrict ws, int n, FILE * __restrict fp)
nl = memchr(fp->_p, '\n', fp->_r);
nconv = __mbsnrtowcs(wsp, &src,
nl != NULL ? (nl - fp->_p + 1) : fp->_r,
n - 1, &fp->_extra->mbstate);
n - 1, &fp->_mbstate);
if (nconv == (size_t)-1)
/* Conversion error */
goto error;
Expand All @@ -86,7 +86,7 @@ fgetws(wchar_t * __restrict ws, int n, FILE * __restrict fp)
if (wsp == ws)
/* EOF */
goto error;
if (!__mbsinit(&fp->_extra->mbstate))
if (!__mbsinit(&fp->_mbstate))
/* Incomplete character */
goto error;
*wsp++ = L'\0';
Expand Down
56 changes: 11 additions & 45 deletions lib/libc/stdio/findfp.c
Original file line number Diff line number Diff line change
Expand Up @@ -54,36 +54,19 @@ int __sdidinit;
#define NDYNAMIC 10 /* add ten more whenever necessary */

#define std(flags, file) \
{0,0,0,flags,file,{0},0,__sF+file,__sclose,__sread,__sseek,__swrite, \
{0}, __sFX + file}
{0,0,0,flags,file,{0},0,__sF+file,__sclose,__sread,__sseek,__swrite}
/* p r w flags file _bf z cookie close read seek write */
/* _ub _extra */

/* the usual - (stdin + stdout + stderr) */
static FILE usual[FOPEN_MAX - 3];
static struct __sFILEX usual_extra[FOPEN_MAX - 3];
static struct glue uglue = { NULL, FOPEN_MAX - 3, usual };

static struct __sFILEX __sFX[3];

/*
* We can't make this 'static' until 6.0-current due to binary
* compatibility concerns. This also means we cannot change the
* sizeof(FILE) until that time either and must continue to use the
* __sFILEX stuff to add to FILE.
*/
FILE __sF[3] = {
static FILE __sF[3] = {
std(__SRD, STDIN_FILENO),
std(__SWR, STDOUT_FILENO),
std(__SWR|__SNBF, STDERR_FILENO)
};

/*
* The following kludge is done to ensure enough binary compatibility
* with future versions of libc. Or rather it allows us to work with
* libraries that have been built with a newer libc that defines these
* symbols and expects libc to provide them. We only have need to support
* i386 because it is the only "old" system we have deployed.
*/
FILE *__stdinp = &__sF[0];
FILE *__stdoutp = &__sF[1];
FILE *__stderrp = &__sF[2];
Expand All @@ -109,25 +92,17 @@ moreglue(n)
{
struct glue *g;
static FILE empty;
static struct __sFILEX emptyx;
FILE *p;
struct __sFILEX *fx;

g = (struct glue *)malloc(sizeof(*g) + ALIGNBYTES + n * sizeof(FILE) +
n * sizeof(struct __sFILEX));
g = (struct glue *)malloc(sizeof(*g) + ALIGNBYTES + n * sizeof(FILE));
if (g == NULL)
return (NULL);
p = (FILE *)ALIGN(g + 1);
fx = (struct __sFILEX *)&p[n];
g->next = NULL;
g->niobs = n;
g->iobs = p;
while (--n >= 0) {
*p = empty;
p->_extra = fx;
*p->_extra = emptyx;
p++, fx++;
}
while (--n >= 0)
*p++ = empty;
return (g);
}

Expand Down Expand Up @@ -175,8 +150,8 @@ __sfp()
fp->_lb._base = NULL; /* no line buffer */
fp->_lb._size = 0;
/* fp->_lock = NULL; */ /* once set always set (reused) */
fp->_extra->orientation = 0;
memset(&fp->_extra->mbstate, 0, sizeof(mbstate_t));
fp->_orientation = 0;
memset(&fp->_mbstate, 0, sizeof(mbstate_t));
return (fp);
}

Expand Down Expand Up @@ -229,17 +204,8 @@ _cleanup()
void
__sinit()
{
int i;

THREAD_LOCK();
if (__sdidinit == 0) {
/* Set _extra for the usual suspects. */
for (i = 0; i < FOPEN_MAX - 3; i++)
usual[i]._extra = &usual_extra[i];

/* Make sure we clean up on exit. */
__cleanup = _cleanup; /* conservative */
__sdidinit = 1;
}
THREAD_UNLOCK();
/* Make sure we clean up on exit. */
__cleanup = _cleanup; /* conservative */
__sdidinit = 1;
}
3 changes: 1 addition & 2 deletions lib/libc/stdio/fputwc.c
Original file line number Diff line number Diff line change
Expand Up @@ -56,8 +56,7 @@ __fputwc(wchar_t wc, FILE *fp)
*buf = (unsigned char)wc;
len = 1;
} else {
if ((len = __wcrtomb(buf, wc, &fp->_extra->mbstate)) ==
(size_t)-1) {
if ((len = __wcrtomb(buf, wc, &fp->_mbstate)) == (size_t)-1) {
fp->_flags |= __SERR;
return (WEOF);
}
Expand Down
2 changes: 1 addition & 1 deletion lib/libc/stdio/fputws.c
Original file line number Diff line number Diff line change
Expand Up @@ -55,7 +55,7 @@ fputws(const wchar_t * __restrict ws, FILE * __restrict fp)
iov.iov_base = buf;
do {
nbytes = __wcsnrtombs(buf, &ws, SIZE_T_MAX, sizeof(buf),
&fp->_extra->mbstate);
&fp->_mbstate);
if (nbytes == (size_t)-1)
goto error;
iov.iov_len = uio.uio_resid = nbytes;
Expand Down
4 changes: 2 additions & 2 deletions lib/libc/stdio/freopen.c
Original file line number Diff line number Diff line change
Expand Up @@ -182,8 +182,8 @@ freopen(file, mode, fp)
if (HASLB(fp))
FREELB(fp);
fp->_lb._size = 0;
fp->_extra->orientation = 0;
memset(&fp->_extra->mbstate, 0, sizeof(mbstate_t));
fp->_orientation = 0;
memset(&fp->_mbstate, 0, sizeof(mbstate_t));

if (f < 0) { /* did not get it after all */
fp->_flags = 0; /* set it free */
Expand Down
8 changes: 4 additions & 4 deletions lib/libc/stdio/fseek.c
Original file line number Diff line number Diff line change
Expand Up @@ -233,7 +233,7 @@ _fseeko(fp, offset, whence, ltest)
*/
if (HASUB(fp)) {
curoff += fp->_r; /* kill off ungetc */
n = fp->_extra->_up - fp->_bf._base;
n = fp->_up - fp->_bf._base;
curoff -= n;
n += fp->_ur;
} else {
Expand All @@ -255,7 +255,7 @@ _fseeko(fp, offset, whence, ltest)
if (HASUB(fp))
FREEUB(fp);
fp->_flags &= ~__SEOF;
memset(&fp->_extra->mbstate, 0, sizeof(mbstate_t));
memset(&fp->_mbstate, 0, sizeof(mbstate_t));
return (0);
}

Expand Down Expand Up @@ -283,7 +283,7 @@ _fseeko(fp, offset, whence, ltest)
fp->_r -= n;
}
fp->_flags &= ~__SEOF;
memset(&fp->_extra->mbstate, 0, sizeof(mbstate_t));
memset(&fp->_mbstate, 0, sizeof(mbstate_t));
return (0);

/*
Expand All @@ -306,6 +306,6 @@ _fseeko(fp, offset, whence, ltest)
fp->_r = 0;
/* fp->_w = 0; */ /* unnecessary (I think...) */
fp->_flags &= ~__SEOF;
memset(&fp->_extra->mbstate, 0, sizeof(mbstate_t));
memset(&fp->_mbstate, 0, sizeof(mbstate_t));
return (0);
}
6 changes: 3 additions & 3 deletions lib/libc/stdio/fwide.c
Original file line number Diff line number Diff line change
Expand Up @@ -42,9 +42,9 @@ fwide(FILE *fp, int mode)

FLOCKFILE(fp);
/* Only change the orientation if the stream is not oriented yet. */
if (mode != 0 && fp->_extra->orientation == 0)
fp->_extra->orientation = mode > 0 ? 1 : -1;
m = fp->_extra->orientation;
if (mode != 0 && fp->_orientation == 0)
fp->_orientation = mode > 0 ? 1 : -1;
m = fp->_orientation;
FUNLOCKFILE(fp);

return (m);
Expand Down
23 changes: 2 additions & 21 deletions lib/libc/stdio/local.h
Original file line number Diff line number Diff line change
Expand Up @@ -80,16 +80,6 @@ extern size_t __fread(void * __restrict buf, size_t size, size_t count,
extern int __sdidinit;


/* hold a buncha junk that would grow the ABI */
struct __sFILEX {
unsigned char *_up; /* saved _p when _p is doing ungetc data */
pthread_mutex_t fl_mutex; /* used for MT-safety */
pthread_t fl_owner; /* current owner */
int fl_count; /* recursive lock count */
int orientation; /* orientation for fwide() */
mbstate_t mbstate; /* multibyte conversion state */
};

/*
* Prepare the given FILE for writing, and return 0 iff it
* can be written now. Otherwise, return EOF and set errno.
Expand Down Expand Up @@ -119,20 +109,11 @@ struct __sFILEX {
(fp)->_lb._base = NULL; \
}

#define INITEXTRA(fp) { \
(fp)->_extra->_up = NULL; \
(fp)->_extra->fl_mutex = PTHREAD_MUTEX_INITIALIZER; \
(fp)->_extra->fl_owner = NULL; \
(fp)->_extra->fl_count = 0; \
(fp)->_extra->orientation = 0; \
memset(&(fp)->_extra->mbstate, 0, sizeof(mbstate_t)); \
}

/*
* Set the orientation for a stream. If o > 0, the stream has wide-
* orientation. If o < 0, the stream has byte-orientation.
*/
#define ORIENT(fp, o) do { \
if ((fp)->_extra->orientation == 0) \
(fp)->_extra->orientation = (o); \
if ((fp)->_orientation == 0) \
(fp)->_orientation = (o); \
} while (0)
2 changes: 1 addition & 1 deletion lib/libc/stdio/refill.c
Original file line number Diff line number Diff line change
Expand Up @@ -106,7 +106,7 @@ __srefill(FILE *fp)
if (HASUB(fp)) {
FREEUB(fp);
if ((fp->_r = fp->_ur) != 0) {
fp->_p = fp->_extra->_up;
fp->_p = fp->_up;
return (0);
}
}
Expand Down
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