net-snmp/snmplib/snprintf.c

813 lines
22 KiB
C

/*
* 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
*
* Portions of this file are copyrighted by:
* Copyright (c) 2016 VMware, Inc. All rights reserved.
* Use is subject to license terms specified in the COPYING file
* distributed with the Net-SNMP package.
*/
/**************************************************************
* 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
*
**************************************************************/
#include <net-snmp/net-snmp-config.h>
#if !defined(HAVE_SNPRINTF) || !defined(HAVE_VSNPRINTF)
#if HAVE_STRING_H
#include <string.h>
#else
#include <strings.h>
#endif
#include <ctype.h>
#include <sys/types.h>
#include <stdarg.h>
#include "snprintf.h"
# define VA_LOCAL_DECL va_list ap
# define VA_START(f) va_start(ap, f)
# define VA_SHIFT(v,t) ; /* no-op for ANSI */
# define VA_END va_end(ap)
#ifdef HAVE_LONG_DOUBLE
#define LDOUBLE long double
#else
#define LDOUBLE double
#endif
static void dopr(char *buffer, size_t maxlen, const char *format,
va_list args);
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);
/*
* 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 char_to_int(p) (p - '0')
#define MAX(p,q) ((p >= q) ? p : q)
static void
dopr(char *buffer, size_t maxlen, const char *format, va_list args)
{
char ch;
long value;
LDOUBLE fvalue;
char *strvalue;
int min;
int max;
int state;
int flags;
int cflags;
size_t currlen;
state = DP_S_DEFAULT;
currlen = flags = cflags = min = 0;
max = -1;
ch = *format++;
while (state != DP_S_DONE) {
if ((ch == '\0') || (currlen >= maxlen))
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(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(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:
/*
* Currently, we don't support Long Long, bummer
*/
switch (ch) {
case 'h':
cflags = DP_C_SHORT;
ch = *format++;
break;
case 'l':
cflags = DP_C_LONG;
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, long);
else if (cflags == DP_C_LONG)
value = va_arg(args, long int);
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 long);
else if (cflags == DP_C_LONG)
value = va_arg(args, unsigned long int);
else
value = 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 long);
else if (cflags == DP_C_LONG)
value = va_arg(args, unsigned long int);
else
value = 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 long);
else if (cflags == DP_C_LONG)
value = va_arg(args, unsigned long int);
else
value = 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);
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);
break;
case 'c':
dopr_outch(buffer, &currlen, maxlen, va_arg(args, int));
break;
case 's':
strvalue = va_arg(args, char *);
if (max < 0)
max = maxlen; /* ie, no max */
fmtstr(buffer, &currlen, maxlen, strvalue, flags, min,
max);
break;
case 'p':
strvalue = (char *) 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 = currlen;
} else if (cflags == DP_C_LONG) {
long int *num;
num = va_arg(args, long int *);
*num = currlen;
} else {
int *num;
num = va_arg(args, int *);
*num = 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 (currlen < maxlen - 1)
buffer[currlen] = '\0';
else
buffer[maxlen - 1] = '\0';
}
static void
fmtstr(char *buffer, size_t * currlen, size_t maxlen,
char *valuein, int flags, int min, int max)
{
int padlen, strln; /* amount to pad */
int cnt = 0;
const char *value = valuein;
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
dprint(1,
(debugfile, "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
ns_pow10(int exp)
{
LDOUBLE result = 1;
while (exp) {
result *= 10;
exp--;
}
return result;
}
static long
ns_round(LDOUBLE value)
{
long intpart;
intpart = value;
value = value - intpart;
if (value >= 0.5)
intpart++;
return intpart;
}
static void
fmtfp(char *buffer, size_t * currlen, size_t maxlen,
LDOUBLE fvalue, int min, int max, int flags)
{
int signvalue = 0;
LDOUBLE ufvalue;
char iconvert[20];
char fconvert[20];
int iplace = 0;
int fplace = 0;
int padlen = 0; /* amount to pad */
int zpadlen = 0;
int caps = 0;
long intpart;
long fracpart;
/*
* 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
intpart = ufvalue;
/*
* 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
*/
fracpart = ns_round((ns_pow10(max)) * (ufvalue - intpart));
if (fracpart >= ns_pow10(max)) {
intpart++;
fracpart -= ns_pow10(max);
}
#ifdef DEBUG_SNPRINTF
dprint(1,
(debugfile, "fmtfp: %f =? %d.%d\n", fvalue, intpart, fracpart));
#endif
/*
* Convert integer part
*/
do {
iconvert[iplace++] =
(caps ? "0123456789ABCDEF" : "0123456789abcdef")[intpart % 10];
intpart = (intpart / 10);
} while (intpart && (iplace < 20));
if (iplace == 20)
iplace--;
iconvert[iplace] = 0;
/*
* Convert fractional part
*/
do {
fconvert[fplace++] =
(caps ? "0123456789ABCDEF" : "0123456789abcdef")[fracpart %
10];
fracpart = (fracpart / 10);
} while (fracpart && (fplace < 20));
if (fplace == 20)
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]);
/*
* Decimal point. This should probably use locale to find the correct
* char to print out.
*/
if (max > 0) {
dopr_outch(buffer, currlen, maxlen, '.');
while (fplace > 0)
dopr_outch(buffer, currlen, maxlen, fconvert[--fplace]);
}
while (zpadlen > 0) {
dopr_outch(buffer, currlen, maxlen, '0');
--zpadlen;
}
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;
}
#ifndef HAVE_VSNPRINTF
int
vsnprintf(char *str, size_t count, const char *fmt, va_list args)
{
str[0] = 0;
dopr(str, count, fmt, args);
return (strlen(str));
}
#endif /* !HAVE_VSNPRINTF */
#ifndef HAVE_SNPRINTF
/*
* VARARGS3
*/
int
snprintf(char *str, size_t count, const char *fmt, ...)
{
VA_LOCAL_DECL;
VA_START(fmt);
VA_SHIFT(str, char *);
VA_SHIFT(count, size_t);
VA_SHIFT(fmt, char *);
(void) vsnprintf(str, count, fmt, ap);
VA_END;
return (strlen(str));
}
#endif /* !HAVE_SNPRINTF */
#ifdef TEST_SNPRINTF
#ifndef LONG_STRING
#define LONG_STRING 1024
#endif
int
main(void)
{
char buf1[LONG_STRING];
char buf2[LONG_STRING];
char *fp_fmt[] = {
"%-1.5f",
"%1.5f",
"%123.9f",
"%10.5f",
"% 10.5f",
"%+22.9f",
"%+4.9f",
"%01.3f",
"%4f",
"%3.1f",
"%3.2f",
"%.0f",
"%.1f",
NULL
};
double fp_nums[] =
{ -1.5, 134.21, 91340.2, 341.1234, 0203.9, 0.96, 0.996,
0.9996, 1.996, 4.136, 0
};
char *int_fmt[] = {
"%-1.5d",
"%1.5d",
"%123.9d",
"%5.5d",
"%10.5d",
"% 10.5d",
"%+22.33d",
"%01.3d",
"%4d",
NULL
};
long int_nums[] = { -1, 134, 91340, 341, 0203, 0 };
int x, y;
int fail = 0;
int num = 0;
printf("Testing snprintf format codes against system sprintf...\n");
for (x = 0; fp_fmt[x] != NULL; x++)
for (y = 0; fp_nums[y] != 0; y++) {
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\tsprintf = %s\n",
fp_fmt[x], buf1, buf2);
fail++;
}
num++;
}
for (x = 0; int_fmt[x] != NULL; x++)
for (y = 0; int_nums[y] != 0; y++) {
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\tsprintf = %s\n",
int_fmt[x], buf1, buf2);
fail++;
}
num++;
}
printf("%d tests failed out of %d.\n", fail, num);
}
#endif /* SNPRINTF_TEST */
#else
int snprintf_unused; /* Suppress "empty translation unit" warning */
#endif /* !HAVE_SNPRINTF */