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/*

 * Copyright (c) 1990 The Regents of the University of California.

 * All rights reserved.

 *

 * Redistribution and use in source and binary forms are permitted

 * provided that the above copyright notice and this paragraph are

 * duplicated in all such forms and that any documentation,

 * advertising materials, and other materials related to such

 * distribution and use acknowledge that the software was developed

 * by the University of California, Berkeley.  The name of the

 * University may not be used to endorse or promote products derived

 * from this software without specific prior written permission.

 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR

 * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED

 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.

 */

/*

FUNCTION

<>, <>, <>---scan and format input

INDEX

	scanf

INDEX

	_scanf_r

INDEX

	fscanf

INDEX

	_fscanf_r

INDEX

	sscanf

INDEX

	_sscanf_r

ANSI_SYNOPSIS

        #include 

        int scanf(const char *restrict <[format]>, ...);

        int fscanf(FILE *restrict <[fd]>, const char *restrict <[format]>, ...);

        int sscanf(const char *restrict <[str]>, const char *restrict <[format]>, ...);

        int _scanf_r(struct _reent *<[ptr]>, const char *restrict <[format]>, ...);

        int _fscanf_r(struct _reent *<[ptr]>, FILE *restrict <[fd]>,

                      const char *restrict <[format]>, ...);

        int _sscanf_r(struct _reent *<[ptr]>, const char *restrict <[str]>,

                      const char *restrict <[format]>, ...);

TRAD_SYNOPSIS

	#include 

	int scanf(<[format]> [, <[arg]>, ...])

	char *<[format]>;

	int fscanf(<[fd]>, <[format]> [, <[arg]>, ...]);

	FILE *<[fd]>;

	char *<[format]>;

	int sscanf(<[str]>, <[format]> [, <[arg]>, ...]);

	char *<[str]>;

	char *<[format]>;

	int _scanf_r(<[ptr]>, <[format]> [, <[arg]>, ...])

        struct _reent *<[ptr]>;

	char *<[format]>;

	int _fscanf_r(<[ptr]>, <[fd]>, <[format]> [, <[arg]>, ...]);

        struct _reent *<[ptr]>;

	FILE *<[fd]>;

	char *<[format]>;

	int _sscanf_r(<[ptr]>, <[str]>, <[format]> [, <[arg]>, ...]);

        struct _reent *<[ptr]>;

	char *<[str]>;

	char *<[format]>;

DESCRIPTION

        <> scans a series of input fields from standard input,

		one character at a time.  Each field is interpreted according to

		a format specifier passed to <> in the format string at

        <<*<[format]>>>.  <> stores the interpreted input from

		each field at the address passed to it as the corresponding argument

		following <[format]>.  You must supply the same number of

		format specifiers and address arguments as there are input fields.

        There must be sufficient address arguments for the given format

        specifiers; if not the results are unpredictable and likely

        disasterous.  Excess address arguments are merely ignored.

        <> often produces unexpected results if the input diverges from

        an expected pattern. Since the combination of <> or <>

        followed by <> is safe and easy, that is the preferred way

        to be certain that a program is synchronized with input at the end

		of a line.

        <> and <> are identical to <>, other than the

        source of input: <> reads from a file, and <>

		from a string.

        The routines <<_scanf_r>>, <<_fscanf_r>>, and <<_sscanf_r>> are reentrant

        versions of <>, <>, and <> that take an additional

        first argument pointing to a reentrancy structure.

        The string at <<*<[format]>>> is a character sequence composed

        of zero or more directives. Directives are composed of

        one or more whitespace characters, non-whitespace characters,

        and format specifications.

        Whitespace characters are blank (<< >>), tab (<<\t>>), or

		newline (<<\n>>).

        When <> encounters a whitespace character in the format string

        it will read (but not store) all consecutive whitespace characters

        up to the next non-whitespace character in the input.

        Non-whitespace characters are all other ASCII characters except the

        percent sign (<<%>>).  When <> encounters a non-whitespace

        character in the format string it will read, but not store

        a matching non-whitespace character.

        Format specifications tell <> to read and convert characters

        from the input field into specific types of values, and store then

        in the locations specified by the address arguments.

        Trailing whitespace is left unread unless explicitly

        matched in the format string.

        The format specifiers must begin with a percent sign (<<%>>)

        and have the following form:

.       %[*][<[width]>][<[size]>]<[type]>

        Each format specification begins with the percent character (<<%>>).

        The other fields are:

	o+

		o *

		an optional marker; if present, it suppresses interpretation and

        assignment of this input field.

        o <[width]>

		an optional maximum field width: a decimal integer,

		which controls the maximum number of characters that

		will be read before converting the current input field.  If the

		input field has fewer than <[width]> characters, <>

		reads all the characters in the field, and then

		proceeds with the next field and its format specification.

		If a whitespace or a non-convertable character occurs

		before <[width]> character are read, the characters up

		to that character are read, converted, and stored.

		Then <> proceeds to the next format specification.

        o size

		<>, <>, <>, <>, <>, and <> are optional size

		characters which override the default way that <>

		interprets the data type of the corresponding argument.

.Modifier   Type(s)

.   hh      d, i, o, u, x, n  convert input to char,

.                             store in char object

.

.   h       d, i, o, u, x, n  convert input to short,

.                             store in short object

.

.   h       D, I, O, U, X     no effect

.           e, f, c, s, p

.

.   j       d, i, o, u, x, n  convert input to intmax_t,

.                             store in intmax_t object

.

.   j       all others        no effect

.

.   l       d, i, o, u, x, n  convert input to long,

.                             store in long object

.

.   l       e, f, g           convert input to double

.                             store in a double object

.

.   l       D, I, O, U, X     no effect

.           c, s, p

.

.   ll      d, i, o, u, x, n  convert to long long,

.                             store in long long

.

.   L       d, i, o, u, x, n  convert to long long,

.                             store in long long

.

.   L       e, f, g, E, G     convert to long double,

.                             store in long double

.

.   L       all others        no effect

.

.   t       d, i, o, u, x, n  convert input to ptrdiff_t,

.                             store in ptrdiff_t object

.

.   t       all others        no effect

.

.   z       d, i, o, u, x, n  convert input to size_t,

.                             store in size_t object

.

.   z       all others        no effect

.

        o <[type]>

		A character to specify what kind of conversion

                <> performs.  Here is a table of the conversion

                characters:

		o+

		o  %

		No conversion is done; the percent character (<<%>>) is stored.

		o c

		Scans one character.  Corresponding <[arg]>: <<(char *arg)>>.

		o s

		Reads a character string into the array supplied.

		Corresponding <[arg]>: <<(char arg[])>>.

		o  [<[pattern]>]

		Reads a non-empty character string into memory

		starting at <[arg]>.  This area must be large

		enough to accept the sequence and a

		terminating null character which will be added

		automatically.  (<[pattern]> is discussed in the paragraph following

		this table). Corresponding <[arg]>: <<(char *arg)>>.

		o d

		Reads a decimal integer into the corresponding <[arg]>: <<(int *arg)>>.

		o D

		Reads a decimal integer into the corresponding

		<[arg]>: <<(long *arg)>>.

		o o

		Reads an octal integer into the corresponding <[arg]>: <<(int *arg)>>.

		o O

		Reads an octal integer into the corresponding <[arg]>: <<(long *arg)>>.

		o u

		Reads an unsigned decimal integer into the corresponding

		<[arg]>: <<(unsigned int *arg)>>.

		o U

		Reads an unsigned decimal integer into the corresponding <[arg]>:

		<<(unsigned long *arg)>>.

		o x,X

		Read a hexadecimal integer into the corresponding <[arg]>:

		<<(int *arg)>>.

		o e, f, g

		Read a floating-point number into the corresponding <[arg]>:

		<<(float *arg)>>.

		o E, F, G

		Read a floating-point number into the corresponding <[arg]>:

		<<(double *arg)>>.

		o  i

		Reads a decimal, octal or hexadecimal integer into the

		corresponding <[arg]>: <<(int *arg)>>.

		o  I

		Reads a decimal, octal or hexadecimal integer into the

		corresponding <[arg]>: <<(long *arg)>>.

		o  n

		Stores the number of characters read in the corresponding

		<[arg]>: <<(int *arg)>>.

		o  p

                Stores a scanned pointer.  ANSI C leaves the details

		to each implementation; this implementation treats

		<<%p>> exactly the same as <<%U>>.  Corresponding

		<[arg]>: <<(void **arg)>>.

                o-

	A <[pattern]> of characters surrounded by square brackets can be used

	instead of the <> type character.  <[pattern]> is a set of

	characters which define a search set of possible characters making up

	the <> input field.  If the first character in the brackets is a

	caret (<<^>>), the search set is inverted to include all ASCII characters

	except those between the brackets.  There is also a range facility

	which you can use as a shortcut. <<%[0-9] >> matches all decimal digits.

	The hyphen must not be the first or last character in the set.

	The character prior to the hyphen must be lexically less than the

	character after it.

	Here are some <[pattern]> examples:

		o+

		o %[abcd]

		matches strings containing only <>, <>, <>, and <>.

		o %[^abcd]

		matches strings containing any characters except <>, <>,

		<>, or <>

		o %[A-DW-Z]

		matches strings containing <>, <>, <>, <>, <>,

		<>, <>, <>

		o %[z-a]

		matches the characters  <>, <<->>, and <>

		o-

	Floating point numbers (for field types <>, <>, <>, <>,

	<>, <>) must correspond to the following general form:

.		[+/-] ddddd[.]ddd [E|e[+|-]ddd]

	where objects inclosed in square brackets are optional, and <>

	represents decimal, octal, or hexadecimal digits.

	o-

RETURNS

        <> returns the number of input fields successfully

        scanned, converted and stored; the return value does

        not include scanned fields which were not stored.

        If <> attempts to read at end-of-file, the return

        value is <>.

        If no fields were stored, the return value is <<0>>.

        <> might stop scanning a particular field before

        reaching the normal field end character, or may

        terminate entirely.

        <> stops scanning and storing the current field

        and moves to the next input field (if any)

        in any of the following situations:

	O+

	o       The assignment suppressing character (<<*>>) appears

	after the <<%>> in the format specification; the current

	input field is scanned but not stored.

	o       <[width]> characters have been read (<[width]> is a

	width specification, a positive decimal integer).

	o       The next character read cannot be converted

	under the the current format (for example,

	if a <> is read when the format is decimal).

	o       The next character in the input field does not appear

	in the search set (or does appear in the inverted search set).

	O-

	When <> stops scanning the current input field for one of

	these reasons, the next character is considered unread and

	used as the first character of the following input field, or the

	first character in a subsequent read operation on the input.

	<> will terminate under the following circumstances:

	O+

	o       The next character in the input field conflicts

	with a corresponding non-whitespace character in the

	format string.

	o       The next character in the input field is <>.

	o       The format string has been exhausted.

	O-

	When the format string contains a character sequence that is

	not part of a format specification, the same character

	sequence must appear in the input; <> will

	scan but not store the matched characters.  If a

	conflict occurs, the first conflicting character remains in the input

	as if it had never been read.

PORTABILITY

<> is ANSI C.

Supporting OS subroutines required: <>, <>, <>,

<>, <>, <>, <>.

*/

#include <_ansi.h>

#include 

#include 

#include 

#ifdef _HAVE_STDC

#include 

#else

#include 

#endif

#include "local.h"

#ifndef _REENT_ONLY

#ifdef _HAVE_STDC

int

_DEFUN(sscanf, (str, fmt),

       _CONST char *__restrict str _AND

       _CONST char * fmt _DOTS)

#else

int

sscanf(str, fmt, va_alist)

       _CONST char *str;

       _CONST char *fmt;

       va_dcl

#endif

{

  int ret;

  va_list ap;

  FILE f;

  f._flags = __SRD | __SSTR;

  f._bf._base = f._p = (unsigned char *) str;

  f._bf._size = f._r = strlen (str);

  f._read = __seofread;

  f._ub._base = NULL;

  f._lb._base = NULL;

  f._file = -1;  /* No file. */

#ifdef _HAVE_STDC

  va_start (ap, fmt);

#else

  va_start (ap);

#endif

  ret = __ssvfscanf_r (_REENT, &f, fmt, ap);

  va_end (ap);

  return ret;

}

#endif /* !_REENT_ONLY */

#ifdef _HAVE_STDC

int

_DEFUN(_sscanf_r, (ptr, str, fmt),

       struct _reent *ptr _AND

       _CONST char *__restrict str   _AND

       _CONST char *__restrict fmt _DOTS)

#else

int

_sscanf_r(ptr, str, fmt, va_alist)

          struct _reent *ptr;

          _CONST char *__restrict str;

          _CONST char *__restrict fmt;

          va_dcl

#endif

{

  int ret;

  va_list ap;

  FILE f;

  f._flags = __SRD | __SSTR;

  f._bf._base = f._p = (unsigned char *) str;

  f._bf._size = f._r = strlen (str);

  f._read = __seofread;

  f._ub._base = NULL;

  f._lb._base = NULL;

  f._file = -1;  /* No file. */

#ifdef _HAVE_STDC

  va_start (ap, fmt);

#else

  va_start (ap);

#endif

  ret = __ssvfscanf_r (ptr, &f, fmt, ap);

  va_end (ap);

  return ret;

}