lib/replace/snprintf.c

説明を見る。

/*
 * 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.
 *
 * Darren Tucker (dtucker@zip.com.au) 2005
 *    Fix bug allowing read overruns of the source string with "%.*s"
 *    Usually harmless unless the read runs outside the process' allocation
 *    (eg if your malloc does guard pages) in which case it will segfault.
 *    From OpenSSH.  Also added test for same.
 *
 * Simo Sorce (idra@samba.org) Jan 2006
 * 
 *    Add support for position independent parameters 
 *    fix fmtstr now it conforms to sprintf wrt min.max
 *
 **************************************************************/

#include "replace.h"
#include "system/locale.h"

#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 */

#if defined(HAVE_SNPRINTF) && defined(HAVE_VSNPRINTF) && defined(HAVE_C99_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 */

/* yes this really must be a ||. Don't muck with this (tridge) */
#if !defined(HAVE_VSNPRINTF) || !defined(HAVE_C99_VSNPRINTF)

#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_CHAR    1
#define DP_C_SHORT   2
#define DP_C_LONG    3
#define DP_C_LDOUBLE 4
#define DP_C_LLONG   5
#define DP_C_SIZET   6

/* Chunk types */
#define CNK_FMT_STR 0
#define CNK_INT     1
#define CNK_OCTAL   2
#define CNK_UINT    3
#define CNK_HEX     4
#define CNK_FLOAT   5
#define CNK_CHAR    6
#define CNK_STRING  7
#define CNK_PTR     8
#define CNK_NUM     9
#define CNK_PRCNT   10

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

struct pr_chunk {
        int type; /* chunk type */
        int num; /* parameter number */
        int min; 
        int max;
        int flags;
        int cflags;
        int start;
        int len;
        LLONG value;
        LDOUBLE fvalue;
        char *strvalue;
        void *pnum;
        struct pr_chunk *min_star;
        struct pr_chunk *max_star;
        struct pr_chunk *next;
};

struct pr_chunk_x {
        struct pr_chunk **chunks;
        int num;
};

static int 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,
                    LLONG 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 struct pr_chunk *new_chunk(void);
static int add_cnk_list_entry(struct pr_chunk_x **list,
                                int max_num, struct pr_chunk *chunk);

static int dopr(char *buffer, size_t maxlen, const char *format, va_list args_in)
{
        char ch;
        int state;
        int pflag;
        int pnum;
        int pfirst;
        size_t currlen;
        va_list args;
        const char *base;
        struct pr_chunk *chunks = NULL;
        struct pr_chunk *cnk = NULL;
        struct pr_chunk_x *clist = NULL;
        int max_pos;
        int ret = -1;

        VA_COPY(args, args_in);

        state = DP_S_DEFAULT;
        pfirst = 1;
        pflag = 0;
        pnum = 0;

        max_pos = 0;
        base = format;
        ch = *format++;
        
        /* retrieve the string structure as chunks */
        while (state != DP_S_DONE) {
                if (ch == '\0') 
                        state = DP_S_DONE;

                switch(state) {
                case DP_S_DEFAULT:
                        
                        if (cnk) {
                                cnk->next = new_chunk();
                                cnk = cnk->next;
                        } else {
                                cnk = new_chunk();
                        }
                        if (!cnk) goto done;
                        if (!chunks) chunks = cnk;
                        
                        if (ch == '%') {
                                state = DP_S_FLAGS;
                                ch = *format++;
                        } else {
                                cnk->type = CNK_FMT_STR;
                                cnk->start = format - base -1;
                                while ((ch != '\0') && (ch != '%')) ch = *format++;
                                cnk->len = format - base - cnk->start -1;
                        }
                        break;
                case DP_S_FLAGS:
                        switch (ch) {
                        case '-':
                                cnk->flags |= DP_F_MINUS;
                                ch = *format++;
                                break;
                        case '+':
                                cnk->flags |= DP_F_PLUS;
                                ch = *format++;
                                break;
                        case ' ':
                                cnk->flags |= DP_F_SPACE;
                                ch = *format++;
                                break;
                        case '#':
                                cnk->flags |= DP_F_NUM;
                                ch = *format++;
                                break;
                        case '0':
                                cnk->flags |= DP_F_ZERO;
                                ch = *format++;
                                break;
                        case 'I':
                                /* internationalization not supported yet */
                                ch = *format++;
                                break;
                        default:
                                state = DP_S_MIN;
                                break;
                        }
                        break;
                case DP_S_MIN:
                        if (isdigit((unsigned char)ch)) {
                                cnk->min = 10 * cnk->min + char_to_int (ch);
                                ch = *format++;
                        } else if (ch == '$') {
                                if (!pfirst && !pflag) {
                                        /* parameters must be all positioned or none */
                                        goto done;
                                }
                                if (pfirst) {
                                        pfirst = 0;
                                        pflag = 1;
                                }
                                if (cnk->min == 0) /* what ?? */
                                        goto done;
                                cnk->num = cnk->min;
                                cnk->min = 0;
                                ch = *format++;
                        } else if (ch == '*') {
                                if (pfirst) pfirst = 0;
                                cnk->min_star = new_chunk();
                                if (!cnk->min_star) /* out of memory :-( */
                                        goto done;
                                cnk->min_star->type = CNK_INT;
                                if (pflag) {
                                        int num;
                                        ch = *format++;
                                        if (!isdigit((unsigned char)ch)) {
                                                /* parameters must be all positioned or none */
                                                goto done;
                                        }
                                        for (num = 0; isdigit((unsigned char)ch); ch = *format++) {
                                                num = 10 * num + char_to_int(ch);
                                        }
                                        cnk->min_star->num = num;
                                        if (ch != '$') /* what ?? */
                                                goto done;
                                } else {
                                        cnk->min_star->num = ++pnum;
                                }
                                max_pos = add_cnk_list_entry(&clist, max_pos, cnk->min_star);
                                if (max_pos == 0) /* out of memory :-( */
                                        goto done;
                                ch = *format++;
                                state = DP_S_DOT;
                        } else {
                                if (pfirst) pfirst = 0;
                                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 (cnk->max < 0)
                                        cnk->max = 0;
                                cnk->max = 10 * cnk->max + char_to_int (ch);
                                ch = *format++;
                        } else if (ch == '$') {
                                if (!pfirst && !pflag) {
                                        /* parameters must be all positioned or none */
                                        goto done;
                                }
                                if (cnk->max <= 0) /* what ?? */
                                        goto done;
                                cnk->num = cnk->max;
                                cnk->max = -1;
                                ch = *format++;
                        } else if (ch == '*') {
                                cnk->max_star = new_chunk();
                                if (!cnk->max_star) /* out of memory :-( */
                                        goto done;
                                cnk->max_star->type = CNK_INT;
                                if (pflag) {
                                        int num;
                                        ch = *format++;
                                        if (!isdigit((unsigned char)ch)) {
                                                /* parameters must be all positioned or none */
                                                goto done;
                                        }
                                        for (num = 0; isdigit((unsigned char)ch); ch = *format++) {
                                                num = 10 * num + char_to_int(ch);
                                        }
                                        cnk->max_star->num = num;
                                        if (ch != '$') /* what ?? */
                                                goto done;
                                } else {
                                        cnk->max_star->num = ++pnum;
                                }
                                max_pos = add_cnk_list_entry(&clist, max_pos, cnk->max_star);
                                if (max_pos == 0) /* out of memory :-( */
                                        goto done;

                                ch = *format++;
                                state = DP_S_MOD;
                        } else {
                                state = DP_S_MOD;
                        }
                        break;
                case DP_S_MOD:
                        switch (ch) {
                        case 'h':
                                cnk->cflags = DP_C_SHORT;
                                ch = *format++;
                                if (ch == 'h') {
                                        cnk->cflags = DP_C_CHAR;
                                        ch = *format++;
                                }
                                break;
                        case 'l':
                                cnk->cflags = DP_C_LONG;
                                ch = *format++;
                                if (ch == 'l') {        /* It's a long long */
                                        cnk->cflags = DP_C_LLONG;
                                        ch = *format++;
                                }
                                break;
                        case 'L':
                                cnk->cflags = DP_C_LDOUBLE;
                                ch = *format++;
                                break;
                        case 'z':
                                cnk->cflags = DP_C_SIZET;
                                ch = *format++;
                                break;
                        default:
                                break;
                        }
                        state = DP_S_CONV;
                        break;
                case DP_S_CONV:
                        if (cnk->num == 0) cnk->num = ++pnum;
                        max_pos = add_cnk_list_entry(&clist, max_pos, cnk);
                        if (max_pos == 0) /* out of memory :-( */
                                goto done;
                        
                        switch (ch) {
                        case 'd':
                        case 'i':
                                cnk->type = CNK_INT;
                                break;
                        case 'o':
                                cnk->type = CNK_OCTAL;
                                cnk->flags |= DP_F_UNSIGNED;
                                break;
                        case 'u':
                                cnk->type = CNK_UINT;
                                cnk->flags |= DP_F_UNSIGNED;
                                break;
                        case 'X':
                                cnk->flags |= DP_F_UP;
                        case 'x':
                                cnk->type = CNK_HEX;
                                cnk->flags |= DP_F_UNSIGNED;
                                break;
                        case 'A':
                                /* hex float not supported yet */
                        case 'E':
                        case 'G':
                        case 'F':
                                cnk->flags |= DP_F_UP;
                        case 'a':
                                /* hex float not supported yet */
                        case 'e':
                        case 'f':
                        case 'g':
                                cnk->type = CNK_FLOAT;
                                break;
                        case 'c':
                                cnk->type = CNK_CHAR;
                                break;
                        case 's':
                                cnk->type = CNK_STRING;
                                break;
                        case 'p':
                                cnk->type = CNK_PTR;
                                break;
                        case 'n':
                                cnk->type = CNK_NUM;
                                break;
                        case '%':
                                cnk->type = CNK_PRCNT;
                                break;
                        default:
                                /* Unknown, bail out*/
                                goto done;
                        }
                        ch = *format++;
                        state = DP_S_DEFAULT;
                        break;
                case DP_S_DONE:
                        break;
                default:
                        /* hmm? */
                        break; /* some picky compilers need this */
                }
        }

        /* retieve the format arguments */
        for (pnum = 0; pnum < max_pos; pnum++) {
                int i;

                if (clist[pnum].num == 0) {
                        /* ignoring a parameter should not be permitted
                         * all parameters must be matched at least once
                         * BUT seem some system ignore this rule ...
                         * at least my glibc based system does --SSS
                         */
#ifdef DEBUG_SNPRINTF
                        printf("parameter at position %d not used\n", pnum+1);
#endif
                        /* eat the parameter */
                        va_arg (args, int);
                        continue;
                }
                for (i = 1; i < clist[pnum].num; i++) {
                        if (clist[pnum].chunks[0]->type != clist[pnum].chunks[i]->type) {
                                /* nooo noo no!
                                 * all the references to a parameter
                                 * must be of the same type
                                 */
                                goto done;
                        }
                }
                cnk = clist[pnum].chunks[0];
                switch (cnk->type) {
                case CNK_INT:
                        if (cnk->cflags == DP_C_SHORT) 
                                cnk->value = va_arg (args, int);
                        else if (cnk->cflags == DP_C_LONG)
                                cnk->value = va_arg (args, long int);
                        else if (cnk->cflags == DP_C_LLONG)
                                cnk->value = va_arg (args, LLONG);
                        else if (cnk->cflags == DP_C_SIZET)
                                cnk->value = va_arg (args, ssize_t);
                        else
                                cnk->value = va_arg (args, int);

                        for (i = 1; i < clist[pnum].num; i++) {
                                clist[pnum].chunks[i]->value = cnk->value;
                        }
                        break;

                case CNK_OCTAL:
                case CNK_UINT:
                case CNK_HEX:
                        if (cnk->cflags == DP_C_SHORT)
                                cnk->value = va_arg (args, unsigned int);
                        else if (cnk->cflags == DP_C_LONG)
                                cnk->value = (unsigned long int)va_arg (args, unsigned long int);
                        else if (cnk->cflags == DP_C_LLONG)
                                cnk->value = (LLONG)va_arg (args, unsigned LLONG);
                        else if (cnk->cflags == DP_C_SIZET)
                                cnk->value = (size_t)va_arg (args, size_t);
                        else
                                cnk->value = (unsigned int)va_arg (args, unsigned int);

                        for (i = 1; i < clist[pnum].num; i++) {
                                clist[pnum].chunks[i]->value = cnk->value;
                        }
                        break;

                case CNK_FLOAT:
                        if (cnk->cflags == DP_C_LDOUBLE)
                                cnk->fvalue = va_arg (args, LDOUBLE);
                        else
                                cnk->fvalue = va_arg (args, double);

                        for (i = 1; i < clist[pnum].num; i++) {
                                clist[pnum].chunks[i]->fvalue = cnk->fvalue;
                        }
                        break;

                case CNK_CHAR:
                        cnk->value = va_arg (args, int);

                        for (i = 1; i < clist[pnum].num; i++) {
                                clist[pnum].chunks[i]->value = cnk->value;
                        }
                        break;

                case CNK_STRING:
                        cnk->strvalue = va_arg (args, char *);
                        if (!cnk->strvalue) cnk->strvalue = "(NULL)";

                        for (i = 1; i < clist[pnum].num; i++) {
                                clist[pnum].chunks[i]->strvalue = cnk->strvalue;
                        }
                        break;

                case CNK_PTR:
                        cnk->strvalue = va_arg (args, void *);
                        for (i = 1; i < clist[pnum].num; i++) {
                                clist[pnum].chunks[i]->strvalue = cnk->strvalue;
                        }
                        break;

                case CNK_NUM:
                        if (cnk->cflags == DP_C_CHAR)
                                cnk->pnum = va_arg (args, char *);
                        else if (cnk->cflags == DP_C_SHORT)
                                cnk->pnum = va_arg (args, short int *);
                        else if (cnk->cflags == DP_C_LONG)
                                cnk->pnum = va_arg (args, long int *);
                        else if (cnk->cflags == DP_C_LLONG)
                                cnk->pnum = va_arg (args, LLONG *);
                        else if (cnk->cflags == DP_C_SIZET)
                                cnk->pnum = va_arg (args, ssize_t *);
                        else
                                cnk->pnum = va_arg (args, int *);

                        for (i = 1; i < clist[pnum].num; i++) {
                                clist[pnum].chunks[i]->pnum = cnk->pnum;
                        }
                        break;

                case CNK_PRCNT:
                        break;

                default:
                        /* what ?? */
                        goto done;
                }
        }
        /* print out the actual string from chunks */
        currlen = 0;
        cnk = chunks;
        while (cnk) {
                int len, min, max;

                if (cnk->min_star) min = cnk->min_star->value;
                else min = cnk->min;
                if (cnk->max_star) max = cnk->max_star->value;
                else max = cnk->max;

                switch (cnk->type) {

                case CNK_FMT_STR:
                        if (maxlen != 0 && maxlen > currlen) {
                                if (maxlen > (currlen + cnk->len)) len = cnk->len;
                                else len = maxlen - currlen;

                                memcpy(&(buffer[currlen]), &(base[cnk->start]), len);
                        }
                        currlen += cnk->len;
                                
                        break;

                case CNK_INT:
                case CNK_UINT:
                        fmtint (buffer, &currlen, maxlen, cnk->value, 10, min, max, cnk->flags);
                        break;

                case CNK_OCTAL:
                        fmtint (buffer, &currlen, maxlen, cnk->value, 8, min, max, cnk->flags);
                        break;

                case CNK_HEX:
                        fmtint (buffer, &currlen, maxlen, cnk->value, 16, min, max, cnk->flags);
                        break;

                case CNK_FLOAT:
                        fmtfp (buffer, &currlen, maxlen, cnk->fvalue, min, max, cnk->flags);
                        break;

                case CNK_CHAR:
                        dopr_outch (buffer, &currlen, maxlen, cnk->value);
                        break;

                case CNK_STRING:
                        if (max == -1) {
                                max = strlen(cnk->strvalue);
                        }
                        fmtstr (buffer, &currlen, maxlen, cnk->strvalue, cnk->flags, min, max);
                        break;

                case CNK_PTR:
                        fmtint (buffer, &currlen, maxlen, (long)(cnk->strvalue), 16, min, max, cnk->flags);
                        break;

                case CNK_NUM:
                        if (cnk->cflags == DP_C_CHAR)
                                *((char *)(cnk->pnum)) = (char)currlen;
                        else if (cnk->cflags == DP_C_SHORT)
                                *((short int *)(cnk->pnum)) = (short int)currlen;
                        else if (cnk->cflags == DP_C_LONG)
                                *((long int *)(cnk->pnum)) = (long int)currlen;
                        else if (cnk->cflags == DP_C_LLONG)
                                *((LLONG *)(cnk->pnum)) = (LLONG)currlen;
                        else if (cnk->cflags == DP_C_SIZET)
                                *((ssize_t *)(cnk->pnum)) = (ssize_t)currlen;
                        else
                                *((int *)(cnk->pnum)) = (int)currlen;
                        break;

                case CNK_PRCNT:
                        dopr_outch (buffer, &currlen, maxlen, '%');
                        break;

                default:
                        /* what ?? */
                        goto done;
                }
                cnk = cnk->next;
        }
        if (maxlen != 0) {
                if (currlen < maxlen - 1) 
                        buffer[currlen] = '\0';
                else if (maxlen > 0) 
                        buffer[maxlen - 1] = '\0';
        }
        ret = currlen;

done:
        va_end(args);

        while (chunks) {
                cnk = chunks->next;
                free(chunks);
                chunks = cnk;
        }
        if (clist) {
                for (pnum = 0; pnum < max_pos; pnum++) {
                        if (clist[pnum].chunks) free(clist[pnum].chunks);
                }
                free(clist);
        }
        return ret;
}

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

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

static void fmtint(char *buffer, size_t *currlen, size_t maxlen,
                    LLONG value, int base, int min, int max, int flags)
{
        int signvalue = 0;
        unsigned LLONG 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;
        LLONG l=0;
        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 9 digits past the decimal because of our 
         * conversion method
         */
        if (max > 9)
                max = 9;

        /* 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)++;
}

static struct pr_chunk *new_chunk(void) {
        struct pr_chunk *new_c = (struct pr_chunk *)malloc(sizeof(struct pr_chunk));

        if (!new_c)
                return NULL;

        new_c->type = 0;
        new_c->num = 0;
        new_c->min = 0;
        new_c->min_star = NULL;
        new_c->max = -1;
        new_c->max_star = NULL;
        new_c->flags = 0;
        new_c->cflags = 0;
        new_c->start = 0;
        new_c->len = 0;
        new_c->value = 0;
        new_c->fvalue = 0;
        new_c->strvalue = NULL;
        new_c->pnum = NULL;
        new_c->next = NULL;

        return new_c;
}

static int add_cnk_list_entry(struct pr_chunk_x **list,
                                int max_num, struct pr_chunk *chunk) {
        struct pr_chunk_x *l;
        struct pr_chunk **c;
        int max;
        int cnum;
        int i, pos;

        if (chunk->num > max_num) {
                max = chunk->num;
        
                if (*list == NULL) {
                        l = (struct pr_chunk_x *)malloc(sizeof(struct pr_chunk_x) * max);
                        pos = 0;
                } else {
                        l = (struct pr_chunk_x *)realloc(*list, sizeof(struct pr_chunk_x) * max);
                        pos = max_num;
                }
                if (l == NULL) {
                        for (i = 0; i < max; i++) {
                                if ((*list)[i].chunks) free((*list)[i].chunks);
                        }
                        return 0;
                }
                for (i = pos; i < max; i++) {
                        l[i].chunks = NULL;
                        l[i].num = 0;
                }
        } else {
                l = *list;
                max = max_num;
        }

        i = chunk->num - 1;
        cnum = l[i].num + 1;
        if (l[i].chunks == NULL) {
                c = (struct pr_chunk **)malloc(sizeof(struct pr_chunk *) * cnum); 
        } else {
                c = (struct pr_chunk **)realloc(l[i].chunks, sizeof(struct pr_chunk *) * cnum);
        }
        if (c == NULL) {
                for (i = 0; i < max; i++) {
                        if (l[i].chunks) free(l[i].chunks);
                }
                return 0;
        }
        c[l[i].num] = chunk;
        l[i].chunks = c;
        l[i].num = cnum;

        *list = l;
        return max;
}

 int vsnprintf (char *str, size_t count, const char *fmt, va_list args)
{
        return dopr(str, count, fmt, args);
}
#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) || !defined(HAVE_C99_VSNPRINTF)
 int 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 ret;
}
#endif

#ifndef HAVE_C99_VSNPRINTF
 int printf(const char *fmt, ...)
{
        va_list ap;
        int ret;
        char *s;

        s = NULL;
        va_start(ap, fmt);
        ret = vasprintf(&s, fmt, ap);
        va_end(ap);

        if (s) {
                fwrite(s, 1, strlen(s), stdout);
        }
        free(s);

        return ret;
}
#endif

#ifndef HAVE_C99_VSNPRINTF
 int fprintf(FILE *stream, const char *fmt, ...)
{
        va_list ap;
        int ret;
        char *s;

        s = NULL;
        va_start(ap, fmt);
        ret = vasprintf(&s, fmt, ap);
        va_end(ap);

        if (s) {
                fwrite(s, 1, strlen(s), stream);
        }
        free(s);

        return ret;
}
#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);
        va_end(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);
        va_end(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 printf(const char *fmt,...);

 int main (void)
{
        char buf1[1024];
        char buf2[1024];
        char *buf3;
        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",
                "%-8.8f",
                "%-9.9f",
                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, 1234567890, 0};
        char *str_fmt[] = {
                "%10.5s",
                "%-10.5s",
                "%5.10s",
                "%-5.10s",
                "%10.1s",
                "%0.10s",
                "%10.0s",
                "%1.10s",
                "%s",
                "%.1s",
                "%.10s",
                "%10s",
                NULL
        };
        char *str_vals[] = {"hello", "a", "", "a longer string", NULL};
#ifdef HAVE_LONG_LONG
        char *ll_fmt[] = {
                "%llu",
                NULL
        };
        LLONG ll_nums[] = { 134, 91340, 341, 0203, 1234567890, 128006186140000000LL, 0};
#endif
        int x, y;
        int fail = 0;
        int num = 0;
        int l1, l2;
        char *ss_fmt[] = {
                "%zd",
                "%zu",
                NULL
        };
        size_t ss_nums[] = {134, 91340, 123456789, 0203, 1234567890, 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++) {
                        buf1[0] = buf2[0] = '\0';
                        l1 = snprintf(buf1, sizeof(buf1), fp_fmt[x], fp_nums[y]);
                        l2 = sprintf (buf2, fp_fmt[x], fp_nums[y]);
                        buf1[1023] = buf2[1023] = '\0';
                        if (strcmp (buf1, buf2) || (l1 != l2)) {
                                printf("snprintf doesn't match Format: %s\n\tsnprintf(%d) = [%s]\n\t sprintf(%d) = [%s]\n", 
                                       fp_fmt[x], l1, buf1, l2, buf2);
                                fail++;
                        }
                        num++;
                }
        }

        for (x = 0; int_fmt[x] ; x++) {
                for (y = 0; int_nums[y] != 0 ; y++) {
                        buf1[0] = buf2[0] = '\0';
                        l1 = snprintf(buf1, sizeof(buf1), int_fmt[x], int_nums[y]);
                        l2 = sprintf (buf2, int_fmt[x], int_nums[y]);
                        buf1[1023] = buf2[1023] = '\0';
                        if (strcmp (buf1, buf2) || (l1 != l2)) {
                                printf("snprintf doesn't match Format: %s\n\tsnprintf(%d) = [%s]\n\t sprintf(%d) = [%s]\n", 
                                       int_fmt[x], l1, buf1, l2, buf2);
                                fail++;
                        }
                        num++;
                }
        }

        for (x = 0; str_fmt[x] ; x++) {
                for (y = 0; str_vals[y] != 0 ; y++) {
                        buf1[0] = buf2[0] = '\0';
                        l1 = snprintf(buf1, sizeof(buf1), str_fmt[x], str_vals[y]);
                        l2 = sprintf (buf2, str_fmt[x], str_vals[y]);
                        buf1[1023] = buf2[1023] = '\0';
                        if (strcmp (buf1, buf2) || (l1 != l2)) {
                                printf("snprintf doesn't match Format: %s\n\tsnprintf(%d) = [%s]\n\t sprintf(%d) = [%s]\n", 
                                       str_fmt[x], l1, buf1, l2, buf2);
                                fail++;
                        }
                        num++;
                }
        }

#ifdef HAVE_LONG_LONG
        for (x = 0; ll_fmt[x] ; x++) {
                for (y = 0; ll_nums[y] != 0 ; y++) {
                        buf1[0] = buf2[0] = '\0';
                        l1 = snprintf(buf1, sizeof(buf1), ll_fmt[x], ll_nums[y]);
                        l2 = sprintf (buf2, ll_fmt[x], ll_nums[y]);
                        buf1[1023] = buf2[1023] = '\0';
                        if (strcmp (buf1, buf2) || (l1 != l2)) {
                                printf("snprintf doesn't match Format: %s\n\tsnprintf(%d) = [%s]\n\t sprintf(%d) = [%s]\n", 
                                       ll_fmt[x], l1, buf1, l2, buf2);
                                fail++;
                        }
                        num++;
                }
        }
#endif

#define BUFSZ 2048

        buf1[0] = buf2[0] = '\0';
        if ((buf3 = malloc(BUFSZ)) == NULL) {
                fail++;
        } else {
                num++;
                memset(buf3, 'a', BUFSZ);
                snprintf(buf1, sizeof(buf1), "%.*s", 1, buf3);
                buf1[1023] = '\0';
                if (strcmp(buf1, "a") != 0) {
                        printf("length limit buf1 '%s' expected 'a'\n", buf1);
                        fail++;
                }
        }

        buf1[0] = buf2[0] = '\0';
        l1 = snprintf(buf1, sizeof(buf1), "%4$*1$d %2$s %3$*1$.*1$f", 3, "pos test", 12.3456, 9);
        l2 = sprintf(buf2, "%4$*1$d %2$s %3$*1$.*1$f", 3, "pos test", 12.3456, 9);
        buf1[1023] = buf2[1023] = '\0';
        if (strcmp(buf1, buf2) || (l1 != l2)) {
                printf("snprintf doesn't match Format: %s\n\tsnprintf(%d) = [%s]\n\t sprintf(%d) = [%s]\n",
                                "%4$*1$d %2$s %3$*1$.*1$f", l1, buf1, l2, buf2);
                fail++;
        }

        buf1[0] = buf2[0] = '\0';
        l1 = snprintf(buf1, sizeof(buf1), "%4$*4$d %2$s %3$*4$.*4$f", 3, "pos test", 12.3456, 9);
        l2 = sprintf(buf2, "%4$*4$d %2$s %3$*4$.*4$f", 3, "pos test", 12.3456, 9);
        buf1[1023] = buf2[1023] = '\0';
        if (strcmp(buf1, buf2)) {
                printf("snprintf doesn't match Format: %s\n\tsnprintf(%d) = [%s]\n\t sprintf(%d) = [%s]\n",
                                "%4$*1$d %2$s %3$*1$.*1$f", l1, buf1, l2, buf2);
                fail++;
        }

        for (x = 0; ss_fmt[x] ; x++) {
                for (y = 0; ss_nums[y] != 0 ; y++) {
                        buf1[0] = buf2[0] = '\0';
                        l1 = snprintf(buf1, sizeof(buf1), ss_fmt[x], ss_nums[y]);
                        l2 = sprintf (buf2, ss_fmt[x], ss_nums[y]);
                        buf1[1023] = buf2[1023] = '\0';
                        if (strcmp (buf1, buf2) || (l1 != l2)) {
                                printf("snprintf doesn't match Format: %s\n\tsnprintf(%d) = [%s]\n\t sprintf(%d) = [%s]\n", 
                                       ss_fmt[x], l1, buf1, l2, buf2);
                                fail++;
                        }
                        num++;
                }
        }
#if 0
        buf1[0] = buf2[0] = '\0';
        l1 = snprintf(buf1, sizeof(buf1), "%lld", (LLONG)1234567890);
        l2 = sprintf(buf2, "%lld", (LLONG)1234567890);
        buf1[1023] = buf2[1023] = '\0';
        if (strcmp(buf1, buf2)) {
                printf("snprintf doesn't match Format: %s\n\tsnprintf(%d) = [%s]\n\t sprintf(%d) = [%s]\n",
                                "%lld", l1, buf1, l2, buf2);
                fail++;
        }

        buf1[0] = buf2[0] = '\0';
        l1 = snprintf(buf1, sizeof(buf1), "%Lf", (LDOUBLE)890.1234567890123);
        l2 = sprintf(buf2, "%Lf", (LDOUBLE)890.1234567890123);
        buf1[1023] = buf2[1023] = '\0';
        if (strcmp(buf1, buf2)) {
                printf("snprintf doesn't match Format: %s\n\tsnprintf(%d) = [%s]\n\t sprintf(%d) = [%s]\n",
                                "%Lf", l1, buf1, l2, buf2);
                fail++;
        }
#endif
        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 */

---