Add %M{essage} extension which prints an errno value as the
corresponding string if possible or numerically otherwise.
It is not currently possible to do the syslog(3) like %m extension
because errno would need to get capatured on entry to the first
function in the printf family, so %M requires you to supply errno
as an argument.
Add %Q{uote} extension which will print a string in double quotes with
appropriate back-slash escapes (only) if necessary.
on probationary terms: it may go away again if it transpires it is
a bad idea.
This extensible printf version will only be used if either
environment variable USE_XPRINTF is defined
or
one of the extension functions are called.
or
the global variable __use_xprintf is set greater than zero.
In all other cases our traditional printf implementation will
be used.
The extensible version is slower than the default printf, mostly
because less opportunity for combining I/O operation exists when
faced with extensions. The default printf on the other hand
is a bad case of spaghetti code.
The extension API has a GLIBC compatible part and a FreeBSD version
of same. The FreeBSD version exists because the GLIBC version may
run afoul of our FILE * locking in multithreaded programs and it
even further eliminate the opportunities for combining I/O operations.
Include three demo extensions which can be enabled if desired: time
(%T), hexdump (%H) and strvis (%V).
%T can format time_t (%T), struct timeval (%lT) and struct timespec (%llT)
in one of two human readable duration formats:
"%.3llT" -> "20349.245"
"%#.3llT" -> "5h39m9.245"
%H will hexdump a sequence of bytes and takes a pointer and a length
argument. The width specifies number of bytes per line.
"%4H" -> "65 72 20 65"
"%+4H" -> "0000 65 72 20 65"
"%#4H" -> "65 72 20 65 |er e|"
"%+#4H" -> "0000 65 72 20 65 |er e|"
%V will dump a string in strvis format.
"%V" -> "Hello\tWor\377ld" (C-style)
"%0V" -> "Hello\011Wor\377ld" (octal)
"%+V" -> "Hello%09Wor%FFld" (http-style)
Tests, comments, bugreports etc are most welcome.
allocate a memory block. sscanf calls __svfscanf which in turn calls
fread, fread triggers mutex initialization but the mutex is not
destroyed in sscanf, this leads to memory leak. To avoid the memory
leak and performance issue, we create a none MT-safe version of fread:
__fread, and instead let __svfscanf call __fread.
PR: threads/90392
Patch submitted by: dhartmei
MFC after: 7 days
For some denormalized long double values, a bug in __hldtoa() (called
from *printf()'s %A format) results in a base 16 digit being rounded
up from 0xf to 0x10.
When this digit is subsequently converted to string format, an index
of 10 reaches past the end of the uppper-case hex/char array, picking
up whatever the code segment happen to contain at that address.
This mostly seem to be some character from the upper half of the
byte range.
When using the %a format instead of %A, the first character past
the end of the lowercase hex/char table happens to be index 0 in
the uppercase hex/char table hextable and therefore the string
representation features a '0', which is supposedly correct.
This leads me to belive that the proper fix _may_ be as simple as
masking all but the lower four bits off after incrementing a hex-digit
in libc/gdtoa/_hdtoa.c:roundup(). I worry however that the upper
bit in 0x10 indicates a carry not carried.
Until das@ or bde@ finds time to visit this issue, extend the
hexdigit arrays with a 17th index containing '?' so that we get a
invalid but consistent and printable output in both %a and %A formats
whenever this bug strikes.
This unmasks the bug in the %a format therefore solving the real
issue may both become easier and more urgent.
Possibly related to: PR 85080
With help by: bde@
(((truncate to zero length) or (create)) (text file)) (for writing)
and not
((truncate file to zero length) or (create text file)) (for writing)
MFC after: 1 week
convenient when the source string isn't null-terminated.
Implement the other conversion functions (mbstowcs(), mbsrtowcs(), wcstombs(),
wcsrtombs()) in terms of these new functions.
writable. Affected callers include fwrite(), put?(), and *printf().
The issue of whether this is the right errno for funopened streams is
unresolved, but that's an obscure case, and some errno is better than
no errno.
Discussed with: bde, jkh
through byte by byte with mbrtowc(). In the usual case (buffer is big
enough to contain the multibyte character, character does not straddle
buffer boundary) this results in only one call to mbrtowc() for each
wide character read.
to the initial state when a stream is opened or seeked upon. Use the
stream's conversion state object instead of a freshly-zeroed one in
fgetwc(), fputwc() and ungetwc().
This is only a performance improvement for now, but it would also be
required in order to support state-dependent encodings.
floating-point support, remove default definition of FLOATING_POINT
from the source, and change the compile-time option to
NO_FLOATING_POINT.
- Remove the HEXFLOAT option. It saves an insignificant amount of
space (<0.1% of the size of libc on i386) and complicates vfprintf()
and checkfmt().
after their change from an array of char to an array of enum.
This fixes problems that occurred when using positional arguments in
format strings, particularly with more than STATIC_ARG_TBL_SIZE (8)
of them.
PR: 65841
Submitted by: Steven Smith (mostly)
ferror(), fileno() and clearerr(), using the value of __isthreaded to
decide between the fast inline single-threaded code and the more
general function equivalent. This gives most of the performance
benefits of the old unsafe macros while preserving thread safety.
structure and call stdio functions. In 5.X this was broken when FILE
locking was introduced into libc.
This change makes most (relevant) stdio functions work again when the
_extra file in FILE isn't initialised (and can't be without a libc
function to do it since the __sFILEX structure is private to libc).
- Update and improve the documentation for %[aA]
o Like %[eE], %[aA] may round the result if a precision is specified.
o Grammar police: Fix a split infinitive.
o The FreeBSD implementation does better than the minimum required
by C99 (literal translation of the mantissa). The digit before
the hexadecimal-point is never 0 unless the number itself is 0.
o Clarify that the exponent field represents a decimal exponent of 2.
o Discuss the fact that multiple valid representations are possible.
o Remove the entry in the BUGS section claiming that %[aA] is not
implemented.
- Remove the entry in the BUGS section claiming that the ' flag for
printing thousands separators is unimplemented for floating-point.
- Remove the entry in the BUGS section claiming that the L modifier
reduces the precision to "double" before conversion.
these are not fully implemented and ifdef'd out, the bugs have
never manifested themselves. Specifically:
- Fix a memory leak in the case where %a follows another
floating-point format.
- Make the %a/%A code behave like %e/%E with respect to
precision.
- It is no longer valid to assume that '-' and '0x' are
mutually exclusive.
- Address other minor issues.
string files (__SSTR flag set). This is necessary because __sputc()
does not respect the __SALC flag, and crashes trying to flush the buffer
instead of resizing it.
PR: 59167
mbstate_t object that they ignore. The zeroing is fairly expensive, and it
will never be necessary in these functions; when we support state-dependent
encodings, we will pass in a pointer to the file's mbstate_t object, and
only zero it at the time the file gets opened.
by sizeof(wchar_t) to get the number of wide characters it contains.
Remove the !hardway micro-optimisation from the CT_INT case to avoid
having to fix it for wide characters.
is made an array of two, to explicitly avoid stack corruption due to
null-terminating (which is doesn't actually happen due to stack alignment
padding).
Submitted by: Ed Moy <emoy@apple.com>
Obtained from: Apple Computer, Inc.
[+|-]Inf, [+|-]NaN, nan(...), and hexidecimal FP constants.
While here, add %a and %A, which are aliases for %e, and
add support for long doubles.
Reviewed by: standards@
%f and sufficiently short %g specifiers where the precision was
explicitly zero, no '#' flag was specified, and the floating point
argument was > 0 and <= 0.5. While at it, add some comments to better
explain the relevant bits of code.
Noticed by: Christoph Kukulies <kuku@physik.rwth-aachen.de>
be printed.
- Fix %f conversions where the number of significant digits is < expt.
This would be a one-line change were it not for thousands separators.
Noticed by tjr.
- Remove some unnecessary code in the parsing of precision specifiers.
- We used to round long double arguments to double. Now we print
them properly.
- Bugs involving '%F', corner cases of '#' and 'g' format
specifiers, and the '.*' precision specifier have been
fixed.
- Added support for the "'" specifier to print thousands' grouping
characters in a locale-dependent manner.
- Implement the __vfprintf() side of hexadecimal floating point
support. All that is still needed is a routine to convert the
mantissa to hex digits one nibble at a time in the style of ultoa().
Reviewed by: silence on standards@
- __vfprintf()'s 'buf' has never been used for floating point, so
don't define it in terms of (incorrect) constants describing
floating point numbers. The actual size needed depends on
sizeof(uintmax_t) and locale details, so I slightly overestimated.
- We don't need a 308-character buffer to store the string "308".
With long doubles and %a we need more than three characters, though.
dtoa() is buggy. The bug would cause incorrect output to be
generated when format strings such as '%5.0f' were used with
nonzero numbers whose magnitude is less than 1.
Reported by: df(1) by way of periodic(8)
Reviewed by: mike
package, a more recent, generalized set of routines. Among the
changes:
- Declare strtof() and strtold() in stdlib.h.
- Add glue to libc to support these routines for all kinds
of ``long double''.
- Update printf() to reflect the fact that dtoa works slightly
differently now.
As soon as I see that nothing has blown up, I will kill
src/lib/libc/stdlib/strtod.c. Soon printf() will be able
to use the new routines to output long doubles without loss
of precision, but numerous bugs in the existing code must
be addressed first.
Reviewed by: bde (briefly), mike (mentor), obrien
Only warnings that could be fixed without changing the generated object
code and without restructuring the source code have been handled.
Reviewed by: /sbin/md5
a NULL filename argument allows a stream's mode to be changed. At the
moment it just recycles the old file descriptor instead of storing the
filename somewhere and using that to reopen the file, as the standard
seems to require. Strictly conforming C99 applications probably can't
tell the difference but POSIX ones can.
PR: 46791
putchar_unlocked(), putc_unlocked(), feof_unlocked(), ferror_unlocked(),
clearerr_unlocked(), and fileno_unlocked(). The first four are required
by POSIX. The rest are provided for consistency.
to be static for 5.0. I may remove this for 5.1 or 5.2. No more
binaries or libarires will be generated with __sF starting as of
yesterday. Originally the plan had been to eliminate this for 5.0,
but we didn't get the __std{in,out,err}p changes merged into -stable
until yesterday (rather than in September 2001 like it should have
been). Given that didn't happen on time, we can't do the other part
of the scheme now.
# Please do not change this without talking to me first.
