printf.c

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/*
 * This file based on printf.c from 'Dlibs' on the atari ST  (RdeBath)
 *
 * 
 *    Dale Schumacher                         399 Beacon Ave.
 *    (alias: Dalnefre')                      St. Paul, MN  55104
 *    [e-mail]                         United States of America
 *  "It's not reality that's important, but how you perceive things."
 */

/* Altered to use stdarg, made the core function vfnprintf.
 * Hooked into the stdio package using 'inside information'
 * Altered sizeof() assumptions, now assumes all integers except chars
 * will be either
 *  sizeof(xxx) == sizeof(long) or sizeof(xxx) == sizeof(short)
 *
 * -RDB
 */

/*
 *                    Manuel Novoa III   Dec 2000
 *
 * The previous vfnprintf routine was almost completely rewritten with the
 * goal of fixing some shortcomings and reducing object size.
 *
 * The summary of changes:
 *
 * Converted print conversion specification parsing from one big switch
 *   to a method using string tables.  This new method verifies that the
 *   conversion flags, field width, precision, qualifier, and specifier
 *   appear in the correct order.  Many questionable specifications were
 *   accepted by the previous code.  This new method also resulted in a
 *   substantial reduction in object size of about 330 bytes (20%) from
 *   the old version (1627 bytes) on i386, even with the following
 *   improvements.
 *
 *     Implemented %n specifier as required by the standards.
 *     Implemented proper handling of precision for int types.
 *     Implemented # for hex and pointer, fixed error for octal rep of 0.
 *     Implemented return of -1 on stream error.
 *
 * Added optional support for the GNU extension %m which prints the string
 *   corresponding the errno.
 *
 * Added optional support for long long ints and unsigned long long ints
 *   using the conversion qualifiers "ll", "L", or "q" (like glibc).
 *
 * Added optional support for doubles in a very limited form.  None of
 *   the formating options are obeyed.  The string returned by __dtostr
 *   is printed directly.
 *
 * Converted to use my (un)signed long (long) to string routines, which are
 * smaller than the previous functions and don't require static buffers.
 *
 * Other Modifications:
 *   Modified sprintf, snprintf, vsprintf, vsnprintf to share on fake-file.
 */

/*
 *                    Manuel Novoa III   Jan 2001
 *
 * Removed fake file from *s*printf functions because of possible problems
 *    if called recursively.  Instead, have sprintf, snprintf, and vsprintf
 *    call vsnprintf which allocates a fake file on the stack.
 * Removed WANT_FPUTC option.  Always use standard putc macro to avoid
 *    problems with the fake file used by the *s*printf functions.
 * Fixed bug parsing flags -- did not restart scan.
 * Added function asprintf.
 * Fixed 0-pad prefixing bug.
 * Converted sizeof(int) == sizeof(long) tests to compile time vs run time.
 *    This saves 112 bytes of code on i386.
 * Fixed precision bug -- when negative set to default.
 * Added function fnprintf to support __dtostr.
 * Added floating point support for doubles.  Yeah!
 * 
 *
 * May 2001     Fixes from Johan Adolfsson ([e-mail])
 *    1) printf("%c",0) returned 0 instead of 1.
 *    2) unrolled loop in asprintf to reduce size and remove compile warning.
 *
 *
 * June 2001
 *    1) fix %p so that "0x" is prepended to outputed hex val
 *    2) fix %p so that "(nil)" is output for (void *)0 to match glibc
 *
 */

/*****************************************************************************/
/*                            OPTIONS                                        */
/*****************************************************************************/
/* The optional support for long longs and doubles comes in two forms.
 *
 *   1) Normal (or partial for doubles) output support.  Set to 1 to turn on.
 *      Adds about 130 bytes for doubles, about 220 bytes for long longs,
 *      and about 275 for both to the base code size of 1163 on i386.
 */

/* These are now set in uClibc_config.h based on Config. */
/*
#define __UCLIBC_HAS_LONG_LONG__         1
#define __UCLIBC_HAS_FLOATS__            1
*/

/*   2) An error message is inserted into the stream, an arg of the
 *      appropriate size is removed from the arglist, and processing
 *      continues.  This is adds less code and may be useful in some
 *      cases.  Set to 1 to turn on.  Adds about 50 bytes for doubles,
 *      about 140 bytes for long longs, and about 175 bytes for both
 *      to the base code size of 1163 on i386.
 */

#define WANT_LONG_LONG_ERROR   0
#define WANT_FLOAT_ERROR      0

/*
 * Set to support GNU extension of %m to print string corresponding to errno.
 *
 * Warning: This adds about 50 bytes (i386) to the code but it also pulls in
 * strerror and the corresponding string table which together are about 3.8k.
 */

#define WANT_GNU_ERRNO         0

/**************************************************************************/

#include <sys/types.h>
#include <fcntl.h>
#include <string.h>
#include <stdlib.h>
#include <limits.h>
#include <assert.h>

#if WANT_GNU_ERRNO
#include <errno.h>
#endif

#ifdef __STDC__
#include <stdarg.h>
#define va_strt      va_start
#else
#include <varargs.h>
#define va_strt(p,i) va_start(p)
#endif

#include "stdio.h"

extern int vfnprintf(FILE * op, size_t max_size,
					 register __const char *fmt, register va_list ap);

#ifdef L_printf
int printf(const char *fmt, ...)
{
	va_list ptr;
	int rv;

	va_strt(ptr, fmt);
	rv = vfnprintf(stdout, -1, fmt, ptr);
	va_end(ptr);
	return rv;
}
#endif

#ifdef L_asprintf
int asprintf(char **app, const char *fmt, ...)
{
	va_list ptr;
	int rv;
	char *p;

	/*
	 * First iteration - find out size of buffer required and allocate it.
	 */
	va_strt(ptr, fmt);
	rv = vsnprintf(NULL, 0, fmt, ptr);
	va_end(ptr);

	p = malloc(++rv);			/* allocate the buffer */
	*app = p;
	if (!p) {
		return -1;
	}

	/*
	 * Second iteration - actually produce output.
	 */
	va_strt(ptr, fmt);
	rv = vsnprintf(p, rv, fmt, ptr);
	va_end(ptr);

	return rv;
}
#endif

#ifdef L_sprintf
int sprintf(char *sp, const char *fmt, ...)
{
	va_list ptr;
	int rv;

	va_strt(ptr, fmt);
	rv = vsnprintf(sp, -1, fmt, ptr);
	va_end(ptr);
	return rv;
}
#endif


#ifdef L_snprintf
int snprintf(char *sp, size_t size, const char *fmt, ...)
{
	va_list ptr;
	int rv;

	va_strt(ptr, fmt);
	rv = vsnprintf(sp, size, fmt, ptr);
	va_end(ptr);
	return rv;
}
#endif

#ifdef L_fprintf
int fprintf(FILE * fp, const char *fmt, ...)
{
	va_list ptr;
	int rv;

	va_strt(ptr, fmt);
	rv = vfnprintf(fp, -1, fmt, ptr);
	va_end(ptr);
	return rv;
}
#endif

#ifdef L_fnprintf
int fnprintf(FILE * fp, size_t size, const char *fmt, ...)
{
	va_list ptr;
	int rv;

	va_strt(ptr, fmt);
	rv = vfnprintf(fp, size, fmt, ptr);
	va_end(ptr);
	return rv;
}
#endif

#ifdef L_vprintf
int vprintf(const char *fmt, va_list ap)
{
	return vfprintf(stdout, fmt, ap);
}
#endif

#ifdef L_vfprintf

int vfprintf(FILE * op, register __const char *fmt, register va_list ap)
{
	return vfnprintf(op, -1, fmt, ap);
}

#endif

#ifdef L_vsprintf
int vsprintf(char *sp, __const char *fmt, va_list ap)
{
	return vsnprintf(sp, -1, fmt, ap);
}
#endif

#ifdef L_vsnprintf
int vsnprintf(char *sp, size_t size, __const char *fmt, va_list ap)
{
	int rv;
	FILE f;

	/*
	 * As we're only using the putc macro in vfnprintf, we don't need to
	 * initialize all FILE f's fields.
	 */
	f.bufwrite = (char *) ((unsigned) -1);
	f.bufpos = sp;
	f.mode = _IOFBF;

	rv = vfnprintf(&f, size, fmt, ap);
	if (size) {					/* If this is going to a buffer, */
		*(f.bufpos) = 0;		/* don't forget to nul-terminate. */
	}
	return rv;
}
#endif

#ifdef L_vdprintf
/*
 * Note: If fd has an associated buffered FILE, bad things happen.
 */
extern int vdprintf(int fd, const char *fmt, va_list ap)
{
	char buf[BUFSIZ];
	FILE f = {buf, 0, buf+sizeof(buf), buf, buf+sizeof(buf), 0, fd, _IOFBF};
	int rv;

	rv = vfnprintf(&f, -1, fmt, ap);

	if (fflush(&f)) {
		return -1;
	}

	return rv;
}
#endif

#ifdef L_vfnprintf

extern char *__ultostr(char *buf, unsigned long uval, int base, int uppercase);
extern char *__ltostr(char *buf, long val, int base, int uppercase);
extern char *__ulltostr(char *buf, unsigned long long uval, int base, int uppercase);
extern char *__lltostr(char *buf, long long val, int base, int uppercase);
extern int __dtostr(FILE * fp, size_t size, long double x,
				  char flag[], int width, int preci, char mode);

enum {
	FLAG_PLUS = 0,
	FLAG_MINUS_LJUSTIFY,
	FLAG_HASH,
	FLAG_0_PAD,
	FLAG_SPACE,
};

/* layout                   01234  */
static const char spec[] = "+-#0 ";

#if defined(__UCLIBC_HAS_LONG_LONG__) || WANT_LONG_LONG_ERROR
static const char qual[] = "hlLq";
#else
static const char qual[] = "hl";
#endif

#if !defined(__UCLIBC_HAS_LONG_LONG__) && WANT_LONG_LONG_ERROR
static const char ll_err[] = "<LONG-LONG>";
#endif

#if !defined(__UCLIBC_HAS_FLOATS__) && WANT_FLOAT_ERROR
static const char dbl_err[] = "<DOUBLE>";
#endif

#if defined(__UCLIBC_HAS_FLOATS__) || WANT_FLOAT_ERROR
/* layout                     012345678901234567   */
static const char u_spec[] = "%nbopxXudicsfgGeEaA";
#else
/* layout                     0123456789012   */
static const char u_spec[] = "%nbopxXudics";
#endif

/* WARNING: u_spec and u_radix need to stay in agreement!!! */
/* u_radix[i] <-> u_spec[i+2] for unsigned entries only */
static const char u_radix[] = "\x02\x08\x10\x10\x10\x0a";