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freebsd/usr.bin/m4/eval.c
Baptiste Daroussin fb3f3d7caf Improve m4 compatibility with GNU m4 extension ** (exponent)
Submitted by:	Marc Espie (espie@OpenBSD.org)
Approved by:	des@ (mentor)
2012-04-15 13:25:51 +00:00

1015 lines
21 KiB
C

/* $OpenBSD: eval.c,v 1.69 2011/03/24 11:23:08 espie Exp $ */
/* $NetBSD: eval.c,v 1.7 1996/11/10 21:21:29 pk Exp $ */
/*
* Copyright (c) 1989, 1993
* The Regents of the University of California. All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* Ozan Yigit at York University.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
/*
* eval.c
* Facility: m4 macro processor
* by: oz
*/
#include <sys/types.h>
#include <err.h>
#include <errno.h>
#include <limits.h>
#include <unistd.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <stddef.h>
#include <string.h>
#include <fcntl.h>
#include "mdef.h"
#include "stdd.h"
#include "extern.h"
#include "pathnames.h"
static void dodefn(const char *);
static void dopushdef(const char *, const char *);
static void dodump(const char *[], int);
static void dotrace(const char *[], int, int);
static void doifelse(const char *[], int);
static int doincl(const char *);
static int dopaste(const char *);
static void dochq(const char *[], int);
static void dochc(const char *[], int);
static void dom4wrap(const char *);
static void dodiv(int);
static void doundiv(const char *[], int);
static void dosub(const char *[], int);
static void map(char *, const char *, const char *, const char *);
static const char *handledash(char *, char *, const char *);
static void expand_builtin(const char *[], int, int);
static void expand_macro(const char *[], int);
static void dump_one_def(const char *, struct macro_definition *);
unsigned long expansion_id;
/*
* eval - eval all macros and builtins calls
* argc - number of elements in argv.
* argv - element vector :
* argv[0] = definition of a user
* macro or NULL if built-in.
* argv[1] = name of the macro or
* built-in.
* argv[2] = parameters to user-defined
* . macro or built-in.
* .
*
* A call in the form of macro-or-builtin() will result in:
* argv[0] = nullstr
* argv[1] = macro-or-builtin
* argv[2] = nullstr
*
* argc is 3 for macro-or-builtin() and 2 for macro-or-builtin
*/
void
eval(const char *argv[], int argc, int td, int is_traced)
{
size_t mark = SIZE_MAX;
expansion_id++;
if (td & RECDEF)
m4errx(1, "expanding recursive definition for %s.", argv[1]);
if (is_traced)
mark = trace(argv, argc, infile+ilevel);
if (td == MACRTYPE)
expand_macro(argv, argc);
else
expand_builtin(argv, argc, td);
if (mark != SIZE_MAX)
finish_trace(mark);
}
/*
* expand_builtin - evaluate built-in macros.
*/
void
expand_builtin(const char *argv[], int argc, int td)
{
int c, n;
int ac;
static int sysval = 0;
#ifdef DEBUG
printf("argc = %d\n", argc);
for (n = 0; n < argc; n++)
printf("argv[%d] = %s\n", n, argv[n]);
fflush(stdout);
#endif
/*
* if argc == 3 and argv[2] is null, then we
* have macro-or-builtin() type call. We adjust
* argc to avoid further checking..
*/
/* we keep the initial value for those built-ins that differentiate
* between builtin() and builtin.
*/
ac = argc;
if (argc == 3 && !*(argv[2]) && !mimic_gnu)
argc--;
switch (td & TYPEMASK) {
case DEFITYPE:
if (argc > 2)
dodefine(argv[2], (argc > 3) ? argv[3] : null);
break;
case PUSDTYPE:
if (argc > 2)
dopushdef(argv[2], (argc > 3) ? argv[3] : null);
break;
case DUMPTYPE:
dodump(argv, argc);
break;
case TRACEONTYPE:
dotrace(argv, argc, 1);
break;
case TRACEOFFTYPE:
dotrace(argv, argc, 0);
break;
case EXPRTYPE:
/*
* doexpr - evaluate arithmetic
* expression
*/
{
int base = 10;
int maxdigits = 0;
const char *errstr;
if (argc > 3) {
base = strtonum(argv[3], 2, 36, &errstr);
if (errstr) {
m4errx(1, "expr: base %s invalid.", argv[3]);
}
}
if (argc > 4) {
maxdigits = strtonum(argv[4], 0, INT_MAX, &errstr);
if (errstr) {
m4errx(1, "expr: maxdigits %s invalid.", argv[4]);
}
}
if (argc > 2)
pbnumbase(expr(argv[2]), base, maxdigits);
break;
}
case IFELTYPE:
if (argc > 4)
doifelse(argv, argc);
break;
case IFDFTYPE:
/*
* doifdef - select one of two
* alternatives based on the existence of
* another definition
*/
if (argc > 3) {
if (lookup_macro_definition(argv[2]) != NULL)
pbstr(argv[3]);
else if (argc > 4)
pbstr(argv[4]);
}
break;
case LENGTYPE:
/*
* dolen - find the length of the
* argument
*/
pbnum((argc > 2) ? strlen(argv[2]) : 0);
break;
case INCRTYPE:
/*
* doincr - increment the value of the
* argument
*/
if (argc > 2)
pbnum(atoi(argv[2]) + 1);
break;
case DECRTYPE:
/*
* dodecr - decrement the value of the
* argument
*/
if (argc > 2)
pbnum(atoi(argv[2]) - 1);
break;
case SYSCTYPE:
/*
* dosys - execute system command
*/
if (argc > 2) {
fflush(stdout);
sysval = system(argv[2]);
}
break;
case SYSVTYPE:
/*
* dosysval - return value of the last
* system call.
*
*/
pbnum(sysval);
break;
case ESYSCMDTYPE:
if (argc > 2)
doesyscmd(argv[2]);
break;
case INCLTYPE:
if (argc > 2)
if (!doincl(argv[2])) {
if (mimic_gnu) {
warn("%s at line %lu: include(%s)",
CURRENT_NAME, CURRENT_LINE, argv[2]);
exit_code = 1;
} else
err(1, "%s at line %lu: include(%s)",
CURRENT_NAME, CURRENT_LINE, argv[2]);
}
break;
case SINCTYPE:
if (argc > 2)
(void) doincl(argv[2]);
break;
#ifdef EXTENDED
case PASTTYPE:
if (argc > 2)
if (!dopaste(argv[2]))
err(1, "%s at line %lu: paste(%s)",
CURRENT_NAME, CURRENT_LINE, argv[2]);
break;
case SPASTYPE:
if (argc > 2)
(void) dopaste(argv[2]);
break;
case FORMATTYPE:
doformat(argv, argc);
break;
#endif
case CHNQTYPE:
dochq(argv, ac);
break;
case CHNCTYPE:
dochc(argv, argc);
break;
case SUBSTYPE:
/*
* dosub - select substring
*
*/
if (argc > 3)
dosub(argv, argc);
break;
case SHIFTYPE:
/*
* doshift - push back all arguments
* except the first one (i.e. skip
* argv[2])
*/
if (argc > 3) {
for (n = argc - 1; n > 3; n--) {
pbstr(rquote);
pbstr(argv[n]);
pbstr(lquote);
pushback(COMMA);
}
pbstr(rquote);
pbstr(argv[3]);
pbstr(lquote);
}
break;
case DIVRTYPE:
if (argc > 2 && (n = atoi(argv[2])) != 0)
dodiv(n);
else {
active = stdout;
oindex = 0;
}
break;
case UNDVTYPE:
doundiv(argv, argc);
break;
case DIVNTYPE:
/*
* dodivnum - return the number of
* current output diversion
*/
pbnum(oindex);
break;
case UNDFTYPE:
/*
* doundefine - undefine a previously
* defined macro(s) or m4 keyword(s).
*/
if (argc > 2)
for (n = 2; n < argc; n++)
macro_undefine(argv[n]);
break;
case POPDTYPE:
/*
* dopopdef - remove the topmost
* definitions of macro(s) or m4
* keyword(s).
*/
if (argc > 2)
for (n = 2; n < argc; n++)
macro_popdef(argv[n]);
break;
case MKTMTYPE:
/*
* dotemp - create a temporary file
*/
if (argc > 2) {
int fd;
char *temp;
temp = xstrdup(argv[2]);
fd = mkstemp(temp);
if (fd == -1)
err(1,
"%s at line %lu: couldn't make temp file %s",
CURRENT_NAME, CURRENT_LINE, argv[2]);
close(fd);
pbstr(temp);
free(temp);
}
break;
case TRNLTYPE:
/*
* dotranslit - replace all characters in
* the source string that appears in the
* "from" string with the corresponding
* characters in the "to" string.
*/
if (argc > 3) {
char *temp;
temp = xalloc(strlen(argv[2])+1, NULL);
if (argc > 4)
map(temp, argv[2], argv[3], argv[4]);
else
map(temp, argv[2], argv[3], null);
pbstr(temp);
free(temp);
} else if (argc > 2)
pbstr(argv[2]);
break;
case INDXTYPE:
/*
* doindex - find the index of the second
* argument string in the first argument
* string. -1 if not present.
*/
pbnum((argc > 3) ? indx(argv[2], argv[3]) : -1);
break;
case ERRPTYPE:
/*
* doerrp - print the arguments to stderr
* file
*/
if (argc > 2) {
for (n = 2; n < argc; n++)
fprintf(stderr, "%s ", argv[n]);
fprintf(stderr, "\n");
}
break;
case DNLNTYPE:
/*
* dodnl - eat-up-to and including
* newline
*/
while ((c = gpbc()) != '\n' && c != EOF)
;
break;
case M4WRTYPE:
/*
* dom4wrap - set up for
* wrap-up/wind-down activity
*/
if (argc > 2)
dom4wrap(argv[2]);
break;
case EXITTYPE:
/*
* doexit - immediate exit from m4.
*/
killdiv();
exit((argc > 2) ? atoi(argv[2]) : 0);
break;
case DEFNTYPE:
if (argc > 2)
for (n = 2; n < argc; n++)
dodefn(argv[n]);
break;
case INDIRTYPE: /* Indirect call */
if (argc > 2)
doindir(argv, argc);
break;
case BUILTINTYPE: /* Builtins only */
if (argc > 2)
dobuiltin(argv, argc);
break;
case PATSTYPE:
if (argc > 2)
dopatsubst(argv, argc);
break;
case REGEXPTYPE:
if (argc > 2)
doregexp(argv, argc);
break;
case LINETYPE:
doprintlineno(infile+ilevel);
break;
case FILENAMETYPE:
doprintfilename(infile+ilevel);
break;
case SELFTYPE:
pbstr(rquote);
pbstr(argv[1]);
pbstr(lquote);
break;
default:
m4errx(1, "eval: major botch.");
break;
}
}
/*
* expand_macro - user-defined macro expansion
*/
void
expand_macro(const char *argv[], int argc)
{
const char *t;
const char *p;
int n;
int argno;
t = argv[0]; /* defn string as a whole */
p = t;
while (*p)
p++;
p--; /* last character of defn */
while (p > t) {
if (*(p - 1) != ARGFLAG)
PUSHBACK(*p);
else {
switch (*p) {
case '#':
pbnum(argc - 2);
break;
case '0':
case '1':
case '2':
case '3':
case '4':
case '5':
case '6':
case '7':
case '8':
case '9':
if ((argno = *p - '0') < argc - 1)
pbstr(argv[argno + 1]);
break;
case '*':
if (argc > 2) {
for (n = argc - 1; n > 2; n--) {
pbstr(argv[n]);
pushback(COMMA);
}
pbstr(argv[2]);
}
break;
case '@':
if (argc > 2) {
for (n = argc - 1; n > 2; n--) {
pbstr(rquote);
pbstr(argv[n]);
pbstr(lquote);
pushback(COMMA);
}
pbstr(rquote);
pbstr(argv[2]);
pbstr(lquote);
}
break;
default:
PUSHBACK(*p);
PUSHBACK('$');
break;
}
p--;
}
p--;
}
if (p == t) /* do last character */
PUSHBACK(*p);
}
/*
* dodefine - install definition in the table
*/
void
dodefine(const char *name, const char *defn)
{
if (!*name && !mimic_gnu)
m4errx(1, "null definition.");
else
macro_define(name, defn);
}
/*
* dodefn - push back a quoted definition of
* the given name.
*/
static void
dodefn(const char *name)
{
struct macro_definition *p;
if ((p = lookup_macro_definition(name)) != NULL) {
if ((p->type & TYPEMASK) == MACRTYPE) {
pbstr(rquote);
pbstr(p->defn);
pbstr(lquote);
} else {
pbstr(p->defn);
pbstr(BUILTIN_MARKER);
}
}
}
/*
* dopushdef - install a definition in the hash table
* without removing a previous definition. Since
* each new entry is entered in *front* of the
* hash bucket, it hides a previous definition from
* lookup.
*/
static void
dopushdef(const char *name, const char *defn)
{
if (!*name && !mimic_gnu)
m4errx(1, "null definition.");
else
macro_pushdef(name, defn);
}
/*
* dump_one_def - dump the specified definition.
*/
static void
dump_one_def(const char *name, struct macro_definition *p)
{
if (!traceout)
traceout = stderr;
if (mimic_gnu) {
if ((p->type & TYPEMASK) == MACRTYPE)
fprintf(traceout, "%s:\t%s\n", name, p->defn);
else {
fprintf(traceout, "%s:\t<%s>\n", name, p->defn);
}
} else
fprintf(traceout, "`%s'\t`%s'\n", name, p->defn);
}
/*
* dodumpdef - dump the specified definitions in the hash
* table to stderr. If nothing is specified, the entire
* hash table is dumped.
*/
static void
dodump(const char *argv[], int argc)
{
int n;
struct macro_definition *p;
if (argc > 2) {
for (n = 2; n < argc; n++)
if ((p = lookup_macro_definition(argv[n])) != NULL)
dump_one_def(argv[n], p);
} else
macro_for_all(dump_one_def);
}
/*
* dotrace - mark some macros as traced/untraced depending upon on.
*/
static void
dotrace(const char *argv[], int argc, int on)
{
int n;
if (argc > 2) {
for (n = 2; n < argc; n++)
mark_traced(argv[n], on);
} else
mark_traced(NULL, on);
}
/*
* doifelse - select one of two alternatives - loop.
*/
static void
doifelse(const char *argv[], int argc)
{
cycle {
if (STREQ(argv[2], argv[3]))
pbstr(argv[4]);
else if (argc == 6)
pbstr(argv[5]);
else if (argc > 6) {
argv += 3;
argc -= 3;
continue;
}
break;
}
}
/*
* doinclude - include a given file.
*/
static int
doincl(const char *ifile)
{
if (ilevel + 1 == MAXINP)
m4errx(1, "too many include files.");
if (fopen_trypath(infile+ilevel+1, ifile) != NULL) {
ilevel++;
bbase[ilevel] = bufbase = bp;
return (1);
} else
return (0);
}
#ifdef EXTENDED
/*
* dopaste - include a given file without any
* macro processing.
*/
static int
dopaste(const char *pfile)
{
FILE *pf;
int c;
if ((pf = fopen(pfile, "r")) != NULL) {
if (synch_lines)
fprintf(active, "#line 1 \"%s\"\n", pfile);
while ((c = getc(pf)) != EOF)
putc(c, active);
(void) fclose(pf);
emit_synchline();
return (1);
} else
return (0);
}
#endif
/*
* dochq - change quote characters
*/
static void
dochq(const char *argv[], int ac)
{
if (ac == 2) {
lquote[0] = LQUOTE; lquote[1] = EOS;
rquote[0] = RQUOTE; rquote[1] = EOS;
} else {
strlcpy(lquote, argv[2], sizeof(lquote));
if (ac > 3) {
strlcpy(rquote, argv[3], sizeof(rquote));
} else {
rquote[0] = ECOMMT; rquote[1] = EOS;
}
}
}
/*
* dochc - change comment characters
*/
static void
dochc(const char *argv[], int argc)
{
/* XXX Note that there is no difference between no argument and a single
* empty argument.
*/
if (argc == 2) {
scommt[0] = EOS;
ecommt[0] = EOS;
} else {
strlcpy(scommt, argv[2], sizeof(scommt));
if (argc == 3) {
ecommt[0] = ECOMMT; ecommt[1] = EOS;
} else {
strlcpy(ecommt, argv[3], sizeof(ecommt));
}
}
}
/*
* dom4wrap - expand text at EOF
*/
static void
dom4wrap(const char *text)
{
if (wrapindex >= maxwraps) {
if (maxwraps == 0)
maxwraps = 16;
else
maxwraps *= 2;
m4wraps = xrealloc(m4wraps, maxwraps * sizeof(*m4wraps),
"too many m4wraps");
}
m4wraps[wrapindex++] = xstrdup(text);
}
/*
* dodivert - divert the output to a temporary file
*/
static void
dodiv(int n)
{
int fd;
oindex = n;
if (n >= maxout) {
if (mimic_gnu)
resizedivs(n + 10);
else
n = 0; /* bitbucket */
}
if (n < 0)
n = 0; /* bitbucket */
if (outfile[n] == NULL) {
char fname[] = _PATH_DIVNAME;
if ((fd = mkstemp(fname)) < 0 ||
(outfile[n] = fdopen(fd, "w+")) == NULL)
err(1, "%s: cannot divert", fname);
if (unlink(fname) == -1)
err(1, "%s: cannot unlink", fname);
}
active = outfile[n];
}
/*
* doundivert - undivert a specified output, or all
* other outputs, in numerical order.
*/
static void
doundiv(const char *argv[], int argc)
{
int ind;
int n;
if (argc > 2) {
for (ind = 2; ind < argc; ind++) {
const char *errstr;
n = strtonum(argv[ind], 1, INT_MAX, &errstr);
if (errstr) {
if (errno == EINVAL && mimic_gnu)
getdivfile(argv[ind]);
} else {
if (n < maxout && outfile[n] != NULL)
getdiv(n);
}
}
}
else
for (n = 1; n < maxout; n++)
if (outfile[n] != NULL)
getdiv(n);
}
/*
* dosub - select substring
*/
static void
dosub(const char *argv[], int argc)
{
const char *ap, *fc, *k;
int nc;
ap = argv[2]; /* target string */
#ifdef EXPR
fc = ap + expr(argv[3]); /* first char */
#else
fc = ap + atoi(argv[3]); /* first char */
#endif
nc = strlen(fc);
if (argc >= 5)
#ifdef EXPR
nc = min(nc, expr(argv[4]));
#else
nc = min(nc, atoi(argv[4]));
#endif
if (fc >= ap && fc < ap + strlen(ap))
for (k = fc + nc - 1; k >= fc; k--)
pushback(*k);
}
/*
* map:
* map every character of s1 that is specified in from
* into s3 and replace in s. (source s1 remains untouched)
*
* This is derived from the a standard implementation of map(s,from,to)
* function of ICON language. Within mapvec, we replace every character
* of "from" with the corresponding character in "to".
* If "to" is shorter than "from", than the corresponding entries are null,
* which means that those characters dissapear altogether.
*/
static void
map(char *dest, const char *src, const char *from, const char *to)
{
const char *tmp;
unsigned char sch, dch;
static char frombis[257];
static char tobis[257];
int i;
char seen[256];
static unsigned char mapvec[256] = {
0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18,
19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35,
36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52,
53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69,
70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86,
87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102,
103, 104, 105, 106, 107, 108, 109, 110, 111, 112, 113, 114, 115,
116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127, 128,
129, 130, 131, 132, 133, 134, 135, 136, 137, 138, 139, 140, 141,
142, 143, 144, 145, 146, 147, 148, 149, 150, 151, 152, 153, 154,
155, 156, 157, 158, 159, 160, 161, 162, 163, 164, 165, 166, 167,
168, 169, 170, 171, 172, 173, 174, 175, 176, 177, 178, 179, 180,
181, 182, 183, 184, 185, 186, 187, 188, 189, 190, 191, 192, 193,
194, 195, 196, 197, 198, 199, 200, 201, 202, 203, 204, 205, 206,
207, 208, 209, 210, 211, 212, 213, 214, 215, 216, 217, 218, 219,
220, 221, 222, 223, 224, 225, 226, 227, 228, 229, 230, 231, 232,
233, 234, 235, 236, 237, 238, 239, 240, 241, 242, 243, 244, 245,
246, 247, 248, 249, 250, 251, 252, 253, 254, 255
};
if (*src) {
if (mimic_gnu) {
/*
* expand character ranges on the fly
*/
from = handledash(frombis, frombis + 256, from);
to = handledash(tobis, tobis + 256, to);
}
tmp = from;
/*
* create a mapping between "from" and
* "to"
*/
for (i = 0; i < 256; i++)
seen[i] = 0;
while (*from) {
if (!seen[(unsigned char)(*from)]) {
mapvec[(unsigned char)(*from)] = (unsigned char)(*to);
seen[(unsigned char)(*from)] = 1;
}
from++;
if (*to)
to++;
}
while (*src) {
sch = (unsigned char)(*src++);
dch = mapvec[sch];
if ((*dest = (char)dch))
dest++;
}
/*
* restore all the changed characters
*/
while (*tmp) {
mapvec[(unsigned char)(*tmp)] = (unsigned char)(*tmp);
tmp++;
}
}
*dest = '\0';
}
/*
* handledash:
* use buffer to copy the src string, expanding character ranges
* on the way.
*/
static const char *
handledash(char *buffer, char *end, const char *src)
{
char *p;
p = buffer;
while(*src) {
if (src[1] == '-' && src[2]) {
unsigned char i;
if ((unsigned char)src[0] <= (unsigned char)src[2]) {
for (i = (unsigned char)src[0];
i <= (unsigned char)src[2]; i++) {
*p++ = i;
if (p == end) {
*p = '\0';
return buffer;
}
}
} else {
for (i = (unsigned char)src[0];
i >= (unsigned char)src[2]; i--) {
*p++ = i;
if (p == end) {
*p = '\0';
return buffer;
}
}
}
src += 3;
} else
*p++ = *src++;
if (p == end)
break;
}
*p = '\0';
return buffer;
}