snprintf.c

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/*
 * NOTE: If you change this file, please merge it into rsync, samba, etc.
 */

/*
 * Copyright Patrick Powell 1995
 * This code is based on code written by Patrick Powell (papowell@astart.com)
 * It may be used for any purpose as long as this notice remains intact
 * on all source code distributions
 */

/**************************************************************
 * Original:
 * Patrick Powell Tue Apr 11 09:48:21 PDT 1995
 * A bombproof version of doprnt (dopr) included.
 * Sigh.  This sort of thing is always nasty do deal with.  Note that
 * the version here does not include floating point...
 *
 * snprintf() is used instead of sprintf() as it does limit checks
 * for string length.  This covers a nasty loophole.
 *
 * The other functions are there to prevent NULL pointers from
 * causing nast effects.
 *
 * More Recently:
 *  Brandon Long <blong@fiction.net> 9/15/96 for mutt 0.43
 *  This was ugly.  It is still ugly.  I opted out of floating point
 *  numbers, but the formatter understands just about everything
 *  from the normal C string format, at least as far as I can tell from
 *  the Solaris 2.5 printf(3S) man page.
 *
 *  Brandon Long <blong@fiction.net> 10/22/97 for mutt 0.87.1
 *    Ok, added some minimal floating point support, which means this
 *    probably requires libm on most operating systems.  Don't yet
 *    support the exponent (e,E) and sigfig (g,G).  Also, fmtint()
 *    was pretty badly broken, it just wasn't being exercised in ways
 *    which showed it, so that's been fixed.  Also, formated the code
 *    to mutt conventions, and removed dead code left over from the
 *    original.  Also, there is now a builtin-test, just compile with:
 *           gcc -DTEST_SNPRINTF -o snprintf snprintf.c -lm
 *    and run snprintf for results.
 * 
 *  Thomas Roessler <roessler@guug.de> 01/27/98 for mutt 0.89i
 *    The PGP code was using unsigned hexadecimal formats. 
 *    Unfortunately, unsigned formats simply didn't work.
 *
 *  Michael Elkins <me@cs.hmc.edu> 03/05/98 for mutt 0.90.8
 *    The original code assumed that both snprintf() and vsnprintf() were
 *    missing.  Some systems only have snprintf() but not vsnprintf(), so
 *    the code is now broken down under HAVE_SNPRINTF and HAVE_VSNPRINTF.
 *
 *  Andrew Tridgell (tridge@samba.org) Oct 1998
 *    fixed handling of %.0f
 *    added test for HAVE_LONG_DOUBLE
 *
 * tridge@samba.org, idra@samba.org, April 2001
 *    got rid of fcvt code (twas buggy and made testing harder)
 *    added C99 semantics
 *
 * date: 2002/12/19 19:56:31;  author: herb;  state: Exp;  lines: +2 -0
 * actually print args for %g and %e
 * 
 * date: 2002/06/03 13:37:52;  author: jmcd;  state: Exp;  lines: +8 -0
 * Since includes.h isn't included here, VA_COPY has to be defined here.  I don't
 * see any include file that is guaranteed to be here, so I'm defining it
 * locally.  Fixes AIX and Solaris builds.
 * 
 * date: 2002/06/03 03:07:24;  author: tridge;  state: Exp;  lines: +5 -13
 * put the ifdef for HAVE_VA_COPY in one place rather than in lots of
 * functions
 * 
 * date: 2002/05/17 14:51:22;  author: jmcd;  state: Exp;  lines: +21 -4
 * Fix usage of va_list passed as an arg.  Use __va_copy before using it
 * when it exists.
 * 
 * date: 2002/04/16 22:38:04;  author: idra;  state: Exp;  lines: +20 -14
 * Fix incorrect zpadlen handling in fmtfp.
 * Thanks to Ollie Oldham <ollie.oldham@metro-optix.com> for spotting it.
 * few mods to make it easier to compile the tests.
 * addedd the "Ollie" test to the floating point ones.
 *
 * Martin Pool (mbp@samba.org) April 2003
 *    Remove NO_CONFIG_H so that the test case can be built within a source
 *    tree with less trouble.
 *    Remove unnecessary SAFE_FREE() definition.
 *
 * Martin Pool (mbp@samba.org) May 2003
 *    Put in a prototype for dummy_snprintf() to quiet compiler warnings.
 *
 *    Move #endif to make sure VA_COPY, LDOUBLE, etc are defined even
 *    if the C library has some snprintf functions already.
 **************************************************************/

#define NULL 0

#ifdef TEST_SNPRINTF /* need math library headers for testing */

/* In test mode, we pretend that this system doesn't have any snprintf
 * functions, regardless of what config.h says. */
#  undef HAVE_SNPRINTF
#  undef HAVE_VSNPRINTF
#  undef HAVE_C99_VSNPRINTF
#  undef HAVE_ASPRINTF
#  undef HAVE_VASPRINTF
#  include <math.h>
#endif /* TEST_SNPRINTF */

#include <stddef.h>
#include <string.h>
#include <sys/types.h>
#include <stdarg.h>
#include <stdlib.h>
#include <ctype.h>

#if defined(HAVE_SNPRINTF) && defined(HAVE_VSNPRINTF)
/* only include stdio.h if we are not re-defining snprintf or vsnprintf */
#include <stdio.h>
 /* make the compiler happy with an empty file */
 void dummy_snprintf(void);
 void dummy_snprintf(void) {} 
#endif /* HAVE_SNPRINTF, etc */

#ifdef HAVE_LONG_DOUBLE
#define LDOUBLE long double
#else
#define LDOUBLE double
#endif

#ifdef HAVE_LONG_LONG
#define LLONG long long
#else
#define LLONG long
#endif

#ifndef VA_COPY
#ifdef HAVE_VA_COPY
#define VA_COPY(dest, src) va_copy(dest, src)
#else
#ifdef HAVE___VA_COPY
#define VA_COPY(dest, src) __va_copy(dest, src)
#else
#define VA_COPY(dest, src) (dest) = (src)
#endif
#endif

/*
 * dopr(): poor man's version of doprintf
 */

/* format read states */
#define DP_S_DEFAULT 0
#define DP_S_FLAGS   1
#define DP_S_MIN     2
#define DP_S_DOT     3
#define DP_S_MAX     4
#define DP_S_MOD     5
#define DP_S_CONV    6
#define DP_S_DONE    7

/* format flags - Bits */
#define DP_F_MINUS      (1 << 0)
#define DP_F_PLUS       (1 << 1)
#define DP_F_SPACE      (1 << 2)
#define DP_F_NUM        (1 << 3)
#define DP_F_ZERO       (1 << 4)
#define DP_F_UP         (1 << 5)
#define DP_F_UNSIGNED   (1 << 6)

/* Conversion Flags */
#define DP_C_SHORT   1
#define DP_C_LONG    2
#define DP_C_LDOUBLE 3
#define DP_C_LLONG   4

#define char_to_int(p) ((p)- '0')
#ifndef MAX
#define MAX(p,q) (((p) >= (q)) ? (p) : (q))
#endif

/* yes this really must be a ||. Don't muck with this (tridge) */
#if !defined(HAVE_VSNPRINTF)

static size_t dopr(char *buffer, size_t maxlen, const char *format, 
                   va_list args_in);
static void fmtstr(char *buffer, size_t *currlen, size_t maxlen,
                    char *value, int flags, int min, int max);
static void fmtint(char *buffer, size_t *currlen, size_t maxlen,
                    long value, int base, int min, int max, int flags);
static void fmtfp(char *buffer, size_t *currlen, size_t maxlen,
                   LDOUBLE fvalue, int min, int max, int flags);
static void dopr_outch(char *buffer, size_t *currlen, size_t maxlen, char c);

static size_t dopr(char *buffer, size_t maxlen, const char *format, va_list args_in)
{
        char ch;
        LLONG value;
        LDOUBLE fvalue;
        char *strvalue;
        int min;
        int max;
        int state;
        int flags;
        int cflags;
        size_t currlen;
        va_list args;

        VA_COPY(args, args_in);
        
        state = DP_S_DEFAULT;
        currlen = flags = cflags = min = 0;
        max = -1;
        ch = *format++;
        
        while (state != DP_S_DONE) {
                if (ch == '\0') 
                        state = DP_S_DONE;

                switch(state) {
                case DP_S_DEFAULT:
                        if (ch == '%') 
                                state = DP_S_FLAGS;
                        else 
                                dopr_outch (buffer, &currlen, maxlen, ch);
                        ch = *format++;
                        break;
                case DP_S_FLAGS:
                        switch (ch) {
                        case '-':
                                flags |= DP_F_MINUS;
                                ch = *format++;
                                break;
                        case '+':
                                flags |= DP_F_PLUS;
                                ch = *format++;
                                break;
                        case ' ':
                                flags |= DP_F_SPACE;
                                ch = *format++;
                                break;
                        case '#':
                                flags |= DP_F_NUM;
                                ch = *format++;
                                break;
                        case '0':
                                flags |= DP_F_ZERO;
                                ch = *format++;
                                break;
                        default:
                                state = DP_S_MIN;
                                break;
                        }
                        break;
                case DP_S_MIN:
                        if (isdigit((unsigned char)ch)) {
                                min = 10*min + char_to_int (ch);
                                ch = *format++;
                        } else if (ch == '*') {
                                min = va_arg (args, int);
                                ch = *format++;
                                state = DP_S_DOT;
                        } else {
                                state = DP_S_DOT;
                        }
                        break;
                case DP_S_DOT:
                        if (ch == '.') {
                                state = DP_S_MAX;
                                ch = *format++;
                        } else { 
                                state = DP_S_MOD;
                        }
                        break;
                case DP_S_MAX:
                        if (isdigit((unsigned char)ch)) {
                                if (max < 0)
                                        max = 0;
                                max = 10*max + char_to_int (ch);
                                ch = *format++;
                        } else if (ch == '*') {
                                max = va_arg (args, int);
                                ch = *format++;
                                state = DP_S_MOD;
                        } else {
                                state = DP_S_MOD;
                        }
                        break;
                case DP_S_MOD:
                        switch (ch) {
                        case 'h':
                                cflags = DP_C_SHORT;
                                ch = *format++;
                                break;
                        case 'l':
                                cflags = DP_C_LONG;
                                ch = *format++;
                                if (ch == 'l') {        /* It's a long long */
                                        cflags = DP_C_LLONG;
                                        ch = *format++;
                                }
                                break;
                        case 'L':
                                cflags = DP_C_LDOUBLE;
                                ch = *format++;
                                break;
                        default:
                                break;
                        }
                        state = DP_S_CONV;
                        break;
                case DP_S_CONV:
                        switch (ch) {
                        case 'd':
                        case 'i':
                                if (cflags == DP_C_SHORT) 
                                        value = va_arg (args, int);
                                else if (cflags == DP_C_LONG)
                                        value = va_arg (args, long int);
                                else if (cflags == DP_C_LLONG)
                                        value = va_arg (args, LLONG);
                                else
                                        value = va_arg (args, int);
                                fmtint (buffer, &currlen, maxlen, value, 10, min, max, flags);
                                break;
                        case 'o':
                                flags |= DP_F_UNSIGNED;
                                if (cflags == DP_C_SHORT)
                                        value = va_arg (args, unsigned int);
                                else if (cflags == DP_C_LONG)
                                        value = (long)va_arg (args, unsigned long int);
                                else if (cflags == DP_C_LLONG)
                                        value = (long)va_arg (args, unsigned LLONG);
                                else
                                        value = (long)va_arg (args, unsigned int);
                                fmtint (buffer, &currlen, maxlen, value, 8, min, max, flags);
                                break;
                        case 'u':
                                flags |= DP_F_UNSIGNED;
                                if (cflags == DP_C_SHORT)
                                        value = va_arg (args, unsigned int);
                                else if (cflags == DP_C_LONG)
                                        value = (long)va_arg (args, unsigned long int);
                                else if (cflags == DP_C_LLONG)
                                        value = (LLONG)va_arg (args, unsigned LLONG);
                                else
                                        value = (long)va_arg (args, unsigned int);
                                fmtint (buffer, &currlen, maxlen, value, 10, min, max, flags);
                                break;
                        case 'X':
                                flags |= DP_F_UP;
                        case 'x':
                                flags |= DP_F_UNSIGNED;
                                if (cflags == DP_C_SHORT)
                                        value = va_arg (args, unsigned int);
                                else if (cflags == DP_C_LONG)
                                        value = (long)va_arg (args, unsigned long int);
                                else if (cflags == DP_C_LLONG)
                                        value = (LLONG)va_arg (args, unsigned LLONG);
                                else
                                        value = (long)va_arg (args, unsigned int);
                                fmtint (buffer, &currlen, maxlen, value, 16, min, max, flags);
                                break;
                        case 'f':
                                if (cflags == DP_C_LDOUBLE)
                                        fvalue = va_arg (args, LDOUBLE);
                                else
                                        fvalue = va_arg (args, double);
                                /* um, floating point? */
                                fmtfp (buffer, &currlen, maxlen, fvalue, min, max, flags);
                                break;
                        case 'E':
                                flags |= DP_F_UP;
                        case 'e':
                                if (cflags == DP_C_LDOUBLE)
                                        fvalue = va_arg (args, LDOUBLE);
                                else
                                        fvalue = va_arg (args, double);
                                fmtfp (buffer, &currlen, maxlen, fvalue, min, max, flags);
                                break;
                        case 'G':
                                flags |= DP_F_UP;
                        case 'g':
                                if (cflags == DP_C_LDOUBLE)
                                        fvalue = va_arg (args, LDOUBLE);
                                else
                                        fvalue = va_arg (args, double);
                                fmtfp (buffer, &currlen, maxlen, fvalue, min, max, flags);
                                break;
                        case 'c':
                                dopr_outch (buffer, &currlen, maxlen, va_arg (args, int));
                                break;
                        case 's':
                                strvalue = va_arg (args, char *);
                                if (!strvalue) strvalue = "(NULL)";
                                if (max == -1) {
                                        max = (int) strlen(strvalue);
                                }
                                if (min > 0 && max >= 0 && min > max) max = min;
                                fmtstr (buffer, &currlen, maxlen, strvalue, flags, min, max);
                                break;
                        case 'p':
                                strvalue = va_arg (args, void *);
                                fmtint (buffer, &currlen, maxlen, (long) strvalue, 16, min, max, flags);
                                break;
                        case 'n':
                                if (cflags == DP_C_SHORT) {
                                        short int *num;
                                        num = va_arg (args, short int *);
                                        *num = (short int) currlen;
                                } else if (cflags == DP_C_LONG) {
                                        long int *num;
                                        num = va_arg (args, long int *);
                                        *num = (long int)currlen;
                                } else if (cflags == DP_C_LLONG) {
                                        LLONG *num;
                                        num = va_arg (args, LLONG *);
                                        *num = (LLONG)currlen;
                                } else {
                                        int *num;
                                        num = va_arg (args, int *);
                                        *num = (int) currlen;
                                }
                                break;
                        case '%':
                                dopr_outch (buffer, &currlen, maxlen, ch);
                                break;
                        case 'w':
                                /* not supported yet, treat as next char */
                                ch = *format++;
                                break;
                        default:
                                /* Unknown, skip */
                                break;
                        }
                        ch = *format++;
                        state = DP_S_DEFAULT;
                        flags = cflags = min = 0;
                        max = -1;
                        break;
                case DP_S_DONE:
                        break;
                default:
                        /* hmm? */
                        break; /* some picky compilers need this */
                }
        }
        if (maxlen != 0) {
                if (currlen < maxlen - 1) 
                        buffer[currlen] = '\0';
                else if (maxlen > 0) 
                        buffer[maxlen - 1] = '\0';
        }
        
        return currlen;
}

static void fmtstr(char *buffer, size_t *currlen, size_t maxlen,
                    char *value, int flags, int min, int max)
{
        int padlen, strln;     /* amount to pad */
        int cnt = 0;

#ifdef DEBUG_SNPRINTF
        printf("fmtstr min=%d max=%d s=[%s]\n", min, max, value);
#endif
        if (value == 0) {
                value = "<NULL>";
        }

        for (strln = 0; value[strln]; ++strln); /* strlen */
        padlen = min - strln;
        if (padlen < 0) 
                padlen = 0;
        if (flags & DP_F_MINUS) 
                padlen = -padlen; /* Left Justify */
        
        while ((padlen > 0) && (cnt < max)) {
                dopr_outch (buffer, currlen, maxlen, ' ');
                --padlen;
                ++cnt;
        }
        while (*value && (cnt < max)) {
                dopr_outch (buffer, currlen, maxlen, *value++);
                ++cnt;
        }
        while ((padlen < 0) && (cnt < max)) {
                dopr_outch (buffer, currlen, maxlen, ' ');
                ++padlen;
                ++cnt;
        }
}

/* Have to handle DP_F_NUM (ie 0x and 0 alternates) */

static void fmtint(char *buffer, size_t *currlen, size_t maxlen,
                    long value, int base, int min, int max, int flags)
{
        int signvalue = 0;
        unsigned long uvalue;
        char convert[20];
        int place = 0;
        int spadlen = 0; /* amount to space pad */
        int zpadlen = 0; /* amount to zero pad */
        int caps = 0;
        
        if (max < 0)
                max = 0;
        
        uvalue = value;
        
        if(!(flags & DP_F_UNSIGNED)) {
                if( value < 0 ) {
                        signvalue = '-';
                        uvalue = -value;
                } else {
                        if (flags & DP_F_PLUS)  /* Do a sign (+/i) */
                                signvalue = '+';
                        else if (flags & DP_F_SPACE)
                                signvalue = ' ';
                }
        }
  
        if (flags & DP_F_UP) caps = 1; /* Should characters be upper case? */

        do {
                convert[place++] =
                        (caps? "0123456789ABCDEF":"0123456789abcdef")
                        [uvalue % (unsigned)base  ];
                uvalue = (uvalue / (unsigned)base );
        } while(uvalue && (place < 20));
        if (place == 20) place--;
        convert[place] = 0;

        zpadlen = max - place;
        spadlen = min - MAX (max, place) - (signvalue ? 1 : 0);
        if (zpadlen < 0) zpadlen = 0;
        if (spadlen < 0) spadlen = 0;
        if (flags & DP_F_ZERO) {
                zpadlen = MAX(zpadlen, spadlen);
                spadlen = 0;
        }
        if (flags & DP_F_MINUS) 
                spadlen = -spadlen; /* Left Justifty */

#ifdef DEBUG_SNPRINTF
        printf("zpad: %d, spad: %d, min: %d, max: %d, place: %d\n",
               zpadlen, spadlen, min, max, place);
#endif

        /* Spaces */
        while (spadlen > 0) {
                dopr_outch (buffer, currlen, maxlen, ' ');
                --spadlen;
        }

        /* Sign */
        if (signvalue) 
                dopr_outch (buffer, currlen, maxlen, signvalue);

        /* Zeros */
        if (zpadlen > 0) {
                while (zpadlen > 0) {
                        dopr_outch (buffer, currlen, maxlen, '0');
                        --zpadlen;
                }
        }

        /* Digits */
        while (place > 0) 
                dopr_outch (buffer, currlen, maxlen, convert[--place]);
  
        /* Left Justified spaces */
        while (spadlen < 0) {
                dopr_outch (buffer, currlen, maxlen, ' ');
                ++spadlen;
        }
}

static LDOUBLE abs_val(LDOUBLE value)
{
        LDOUBLE result = value;

        if (value < 0)
                result = -value;
        
        return result;
}

static LDOUBLE POW10(int exp)
{
        LDOUBLE result = 1;
        
        while (exp) {
                result *= 10;
                exp--;
        }
  
        return result;
}

static LLONG ROUND(LDOUBLE value)
{
        LLONG intpart;

        intpart = (LLONG)value;
        value = value - intpart;
        if (value >= 0.5) intpart++;
        
        return intpart;
}

/* a replacement for modf that doesn't need the math library. Should
   be portable, but slow */
static double my_modf(double x0, double *iptr)
{
        int i;
        long l;
        double x = x0;
        double f = 1.0;

        for (i=0;i<100;i++) {
                l = (long)x;
                if (l <= (x+1) && l >= (x-1)) break;
                x *= 0.1;
                f *= 10.0;
        }

        if (i == 100) {
                /* yikes! the number is beyond what we can handle. What do we do? */
                (*iptr) = 0;
                return 0;
        }

        if (i != 0) {
                double i2;
                double ret;

                ret = my_modf(x0-l*f, &i2);
                (*iptr) = l*f + i2;
                return ret;
        } 

        (*iptr) = l;
        return x - (*iptr);
}


static void fmtfp (char *buffer, size_t *currlen, size_t maxlen,
                   LDOUBLE fvalue, int min, int max, int flags)
{
        int signvalue = 0;
        double ufvalue;
        char iconvert[311];
        char fconvert[311];
        int iplace = 0;
        int fplace = 0;
        int padlen = 0; /* amount to pad */
        int zpadlen = 0; 
        int caps = 0;
        int idx;
        double intpart;
        double fracpart;
        double temp;
  
        /* 
         * AIX manpage says the default is 0, but Solaris says the default
         * is 6, and sprintf on AIX defaults to 6
         */
        if (max < 0)
                max = 6;

        ufvalue = abs_val (fvalue);

        if (fvalue < 0) {
                signvalue = '-';
        } else {
                if (flags & DP_F_PLUS) { /* Do a sign (+/i) */
                        signvalue = '+';
                } else {
                        if (flags & DP_F_SPACE)
                                signvalue = ' ';
                }
        }

#if 0
        if (flags & DP_F_UP) caps = 1; /* Should characters be upper case? */
#endif

#if 0
         if (max == 0) ufvalue += 0.5; /* if max = 0 we must round */
#endif

        /* 
         * Sorry, we only support 16 digits past the decimal because of our 
         * conversion method
         */
        if (max > 16)
                max = 16;

        /* We "cheat" by converting the fractional part to integer by
         * multiplying by a factor of 10
         */

        temp = ufvalue;
        my_modf(temp, &intpart);

        fracpart = ROUND((POW10(max)) * (ufvalue - intpart));
        
        if (fracpart >= POW10(max)) {
                intpart++;
                fracpart -= POW10(max);
        }


        /* Convert integer part */
        do {
                temp = intpart*0.1;
                my_modf(temp, &intpart);
                idx = (int) ((temp -intpart +0.05)* 10.0);
                /* idx = (int) (((double)(temp*0.1) -intpart +0.05) *10.0); */
                /* printf ("%llf, %f, %x\n", temp, intpart, idx); */
                iconvert[iplace++] =
                        (caps? "0123456789ABCDEF":"0123456789abcdef")[idx];
        } while (intpart && (iplace < 311));
        if (iplace == 311) iplace--;
        iconvert[iplace] = 0;

        /* Convert fractional part */
        if (fracpart)
        {
                do {
                        temp = fracpart*0.1;
                        my_modf(temp, &fracpart);
                        idx = (int) ((temp -fracpart +0.05)* 10.0);
                        /* idx = (int) ((((temp/10) -fracpart) +0.05) *10); */
                        /* printf ("%lf, %lf, %ld\n", temp, fracpart, idx ); */
                        fconvert[fplace++] =
                        (caps? "0123456789ABCDEF":"0123456789abcdef")[idx];
                } while(fracpart && (fplace < 311));
                if (fplace == 311) fplace--;
        }
        fconvert[fplace] = 0;
  
        /* -1 for decimal point, another -1 if we are printing a sign */
        padlen = min - iplace - max - 1 - ((signvalue) ? 1 : 0); 
        zpadlen = max - fplace;
        if (zpadlen < 0) zpadlen = 0;
        if (padlen < 0) 
                padlen = 0;
        if (flags & DP_F_MINUS) 
                padlen = -padlen; /* Left Justifty */
        
        if ((flags & DP_F_ZERO) && (padlen > 0)) {
                if (signvalue) {
                        dopr_outch (buffer, currlen, maxlen, signvalue);
                        --padlen;
                        signvalue = 0;
                }
                while (padlen > 0) {
                        dopr_outch (buffer, currlen, maxlen, '0');
                        --padlen;
                }
        }
        while (padlen > 0) {
                dopr_outch (buffer, currlen, maxlen, ' ');
                --padlen;
        }
        if (signvalue) 
                dopr_outch (buffer, currlen, maxlen, signvalue);
        
        while (iplace > 0) 
                dopr_outch (buffer, currlen, maxlen, iconvert[--iplace]);

#ifdef DEBUG_SNPRINTF
        printf("fmtfp: fplace=%d zpadlen=%d\n", fplace, zpadlen);
#endif

        /*
         * Decimal point.  This should probably use locale to find the correct
         * char to print out.
         */
        if (max > 0) {
                dopr_outch (buffer, currlen, maxlen, '.');
                
                while (zpadlen > 0) {
                        dopr_outch (buffer, currlen, maxlen, '0');
                        --zpadlen;
                }

                while (fplace > 0) 
                        dopr_outch (buffer, currlen, maxlen, fconvert[--fplace]);
        }

        while (padlen < 0) {
                dopr_outch (buffer, currlen, maxlen, ' ');
                ++padlen;
        }
}

static void dopr_outch(char *buffer, size_t *currlen, size_t maxlen, char c)
{
        if (*currlen < maxlen) {
                buffer[(*currlen)] = c;
        }
        (*currlen)++;
}

 int smb_vsnprintf (char *str, size_t count, const char *fmt, va_list args)
{
        return (int) dopr(str, count, fmt, args);
}
#define vsnprintf smb_vsnprintf
#endif

/* yes this really must be a ||. Don't muck with this (tridge)
 *
 * The logic for these two is that we need our own definition if the
 * OS *either* has no definition of *sprintf, or if it does have one
 * that doesn't work properly according to the autoconf test.
 */
#if !defined(HAVE_SNPRINTF)
int smb_snprintf(char *str,size_t count,const char *fmt,...)
{
        size_t ret;
        va_list ap;
    
        va_start(ap, fmt);
        ret = vsnprintf(str, count, fmt, ap);
        va_end(ap);
        return (int) ret;
}
#define snprintf smb_snprintf
#endif

#endif 

#ifndef HAVE_VASPRINTF
 int vasprintf(char **ptr, const char *format, va_list ap)
{
        int ret;
        va_list ap2;

        VA_COPY(ap2, ap);
        
        ret = vsnprintf(NULL, 0, format, ap2);
        if (ret <= 0) return ret;

        (*ptr) = (char *)malloc(ret+1);
        if (!*ptr) return -1;

        VA_COPY(ap2, ap);

        ret = vsnprintf(*ptr, ret+1, format, ap2);

        return ret;
}
#endif


#ifndef HAVE_ASPRINTF
 int asprintf(char **ptr, const char *format, ...)
{
        va_list ap;
        int ret;
        
        *ptr = NULL;
        va_start(ap, format);
        ret = vasprintf(ptr, format, ap);
        va_end(ap);

        return ret;
}
#endif

#ifdef TEST_SNPRINTF

 int sprintf(char *str,const char *fmt,...);

 int main (void)
{
        char buf1[1024];
        char buf2[1024];
        char *fp_fmt[] = {
                "%1.1f",
                "%-1.5f",
                "%1.5f",
                "%123.9f",
                "%10.5f",
                "% 10.5f",
                "%+22.9f",
                "%+4.9f",
                "%01.3f",
                "%4f",
                "%3.1f",
                "%3.2f",
                "%.0f",
                "%f",
                "-16.16f",
                NULL
        };
        double fp_nums[] = { 6442452944.1234, -1.5, 134.21, 91340.2, 341.1234, 203.9, 0.96, 0.996, 
                             0.9996, 1.996, 4.136, 5.030201, 0.00205,
                             /* END LIST */ 0};
        char *int_fmt[] = {
                "%-1.5d",
                "%1.5d",
                "%123.9d",
                "%5.5d",
                "%10.5d",
                "% 10.5d",
                "%+22.33d",
                "%01.3d",
                "%4d",
                "%d",
                NULL
        };
        long int_nums[] = { -1, 134, 91340, 341, 0203, 0};
        char *str_fmt[] = {
                "10.5s",
                "5.10s",
                "10.1s",
                "0.10s",
                "10.0s",
                "1.10s",
                "%s",
                "%.1s",
                "%.10s",
                "%10s",
                NULL
        };
        char *str_vals[] = {"hello", "a", "", "a longer string", NULL};
        int x, y;
        int fail = 0;
        int num = 0;

        printf ("Testing snprintf format codes against system sprintf...\n");

        for (x = 0; fp_fmt[x] ; x++) {
                for (y = 0; fp_nums[y] != 0 ; y++) {
                        int l1 = snprintf(NULL, 0, fp_fmt[x], fp_nums[y]);
                        int l2 = snprintf(buf1, sizeof(buf1), fp_fmt[x], fp_nums[y]);
                        sprintf (buf2, fp_fmt[x], fp_nums[y]);
                        if (strcmp (buf1, buf2)) {
                                printf("snprintf doesn't match Format: %s\n\tsnprintf = [%s]\n\t sprintf = [%s]\n", 
                                       fp_fmt[x], buf1, buf2);
                                fail++;
                        }
                        if (l1 != l2) {
                                printf("snprintf l1 != l2 (%d %d) %s\n", l1, l2, fp_fmt[x]);
                                fail++;
                        }
                        num++;
                }
        }

        for (x = 0; int_fmt[x] ; x++) {
                for (y = 0; int_nums[y] != 0 ; y++) {
                        int l1 = snprintf(NULL, 0, int_fmt[x], int_nums[y]);
                        int l2 = snprintf(buf1, sizeof(buf1), int_fmt[x], int_nums[y]);
                        sprintf (buf2, int_fmt[x], int_nums[y]);
                        if (strcmp (buf1, buf2)) {
                                printf("snprintf doesn't match Format: %s\n\tsnprintf = [%s]\n\t sprintf = [%s]\n", 
                                       int_fmt[x], buf1, buf2);
                                fail++;
                        }
                        if (l1 != l2) {
                                printf("snprintf l1 != l2 (%d %d) %s\n", l1, l2, int_fmt[x]);
                                fail++;
                        }
                        num++;
                }
        }

        for (x = 0; str_fmt[x] ; x++) {
                for (y = 0; str_vals[y] != 0 ; y++) {
                        int l1 = snprintf(NULL, 0, str_fmt[x], str_vals[y]);
                        int l2 = snprintf(buf1, sizeof(buf1), str_fmt[x], str_vals[y]);
                        sprintf (buf2, str_fmt[x], str_vals[y]);
                        if (strcmp (buf1, buf2)) {
                                printf("snprintf doesn't match Format: %s\n\tsnprintf = [%s]\n\t sprintf = [%s]\n", 
                                       str_fmt[x], buf1, buf2);
                                fail++;
                        }
                        if (l1 != l2) {
                                printf("snprintf l1 != l2 (%d %d) %s\n", l1, l2, str_fmt[x]);
                                fail++;
                        }
                        num++;
                }
        }

        printf ("%d tests failed out of %d.\n", fail, num);

        printf("seeing how many digits we support\n");
        {
                double v0 = 0.12345678901234567890123456789012345678901;
                for (x=0; x<100; x++) {
                        double p = pow(10, x); 
                        double r = v0*p;
                        snprintf(buf1, sizeof(buf1), "%1.1f", r);
                        sprintf(buf2,                "%1.1f", r);
                        if (strcmp(buf1, buf2)) {
                                printf("we seem to support %d digits\n", x-1);
                                break;
                        }
                }
        }

        return 0;
}
#endif /* TEST_SNPRINTF */

---