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20 KiB
C

/*
* Networking binary buffers pack/unpack library
*
* (c) Alexander Vdolainen 2016 <avdolainen@zoho.com>
* (c) Alexander Vdolainen 2017, 2018 <alex@vapaa.xyz>
*
* libndbuf is free software: you can redistribute it and/or modify it
* under the terms of the GNU Lesser General Public License as published
* by the Free Software Foundation, either version 2.1 of the License, or
* (at your option) any later version.
*
* libndbuf is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
* See the GNU Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.";
*
*/
#include <stdint.h>
#include <stdlib.h>
#include <string.h>
#include <stdarg.h>
#include <sys/types.h>
#include <arpa/inet.h>
#include <errno.h>
#include <ndbuf/ndbuf.h>
static inline uint64_t ntohll(uint64_t n)
{
#ifdef WORDS_BIGENDIAN
return n;
#else /* WORDS_BIGENDIAN */
return (uint64_t)(((uint64_t)(n) << 56) | \
(((uint64_t)(n) << 40) & 0xff000000000000ULL) | \
(((uint64_t)(n) << 24) & 0xff0000000000ULL) | \
(((uint64_t)(n) << 8) & 0xff00000000ULL) | \
(((uint64_t)(n) >> 8) & 0xff000000ULL) | \
(((uint64_t)(n) >> 24) & 0xff0000ULL) | \
(((uint64_t)(n) >> 40) & 0xff00ULL) | \
((uint64_t)(n) >> 56));
#endif /* WORDS_BIGENDIAN */
}
/* allocation, freeing */
#define DEFAULT_PREALLOC_SIZE 256
#define NDBUF_MAXLENGTH 6*(1024*1024)
/* allocate raw buffer with defaults preallocation */
ndbuf_t *ndbuf_new(void)
{
ndbuf_t *b = malloc(sizeof(ndbuf_t));
if(!b) return NULL;
if(!(b->raw = malloc(DEFAULT_PREALLOC_SIZE))) {
free(b);
b = NULL;
} else {
b->rlength = DEFAULT_PREALLOC_SIZE;
b->ulength = b->curr = 0;
b->flags = 0;
}
return b;
}
/* create ndbuf from raw buffer */
ndbuf_t *ndbuf_new_frombuf(char *buf, size_t buf_len, void (*freebuf)(char *))
{
ndbuf_t *b = NULL;
if(!buf || !buf_len) return NULL;
if(!(b = malloc(sizeof(ndbuf_t)))) return NULL;
/* init buffer */
b->raw = buf;
b->rlength = b->ulength = buf_len;
b->flags = b->curr = 0;
b->freebuf = freebuf;
b->flags |= NDBUF_NREA;
return b;
}
/* will do the same as ndbuf_new but will allocate given length */
ndbuf_t *ndbuf_new_palloc(uint32_t alen)
{
ndbuf_t *b = NULL;
if(alen > NDBUF_MAXLENGTH) return NULL;
if(!(b = malloc(sizeof(ndbuf_t)))) return NULL;
else memset(b, 0, sizeof(ndbuf_t));
if(!(b->raw = malloc(alen))) {
free(b);
b = NULL;
} else b->rlength = alen;
return b;
}
ndbuf_t *ndbuf_new_wmops(const struct ndbuf_memops *o, const size_t blk_len)
{
ndbuf_t *b = NULL;
if(!o) return NULL;
else { /* avoid nil calls */
if(!o->alloc || !o->free) return NULL;
}
if(!(b = malloc(sizeof(ndbuf_t)))) return NULL;
else memset(b, 0, sizeof(ndbuf_t));
if(blk_len <= 0) b->blk_size = DEFAULT_PREALLOC_SIZE;
if(!(b->raw = o->alloc(b->blk_size))) {
free(b);
return NULL;
} else {
b->rlength = b->blk_size;
b->ulength = b->curr = 0;
b->mop = o;
b->flags |= NDBUF_UCMO;
}
return b;
}
/* free all allocated space and buffer itself */
void ndbuf_free(ndbuf_t *b)
{
const struct ndbuf_memops *o = NULL;
if(!b) return;
if(b->flags & NDBUF_UCMO) o = b->mop;
if(o) {
if((b->flags & NDBUF_BURN) && o->zero) o->zero((void *)b->raw, b->rlength);
o->free(b->raw);
} else {
if((b->flags & NDBUF_BURN) && b->raw)
memset(b->raw, 0, b->rlength);
if((b->flags & NDBUF_NREA) && b->freebuf) b->freebuf(b->raw);
else if(b->raw) free(b->raw);
}
if(b->flags & NDBUF_BURN) memset(b, 0, sizeof(ndbuf_t));
free(b);
return;
}
/* read/write */
/* read different types, should return the size of the
* ridden data, otherwise error occurs */
uint32_t ndbuf_read_u8(ndbuf_t *b, uint8_t *o)
{
uint8_t u;
if(!b || !o) return 0;
if(!b->raw) return 0;
if(b->curr >= b->ulength) return 0;
u = *((uint8_t*)(b->raw + b->curr));
b->curr += sizeof(uint8_t);
*o = u;
return sizeof(uint8_t);
}
uint32_t ndbuf_read_u16(ndbuf_t *b, uint16_t *o)
{
uint16_t u;
if(!b || !o) return 0;
if(!b->raw) return 0;
if(b->curr >= b->ulength) return 0;
if(b->curr + sizeof(uint16_t) > b->ulength) return 0;
u = *((uint16_t *)(b->raw + b->curr));
b->curr += sizeof(uint16_t);
*o = ntohs(u);
return sizeof(uint16_t);
}
uint32_t ndbuf_read_u32(ndbuf_t *b, uint32_t *o)
{
uint32_t u;
if(!b || !o) return 0;
if(!b->raw) return 0;
if(b->curr >= b->ulength) return 0;
if(b->curr + sizeof(uint32_t) > b->ulength) return 0;
u = *((uint32_t *)(b->raw + b->curr));
b->curr += sizeof(uint32_t);
*o = ntohl(u);
return sizeof(uint32_t);
}
uint32_t ndbuf_read_u64(ndbuf_t *b, uint64_t *o)
{
uint64_t u;
if(!b || !o) return 0;
if(!b->raw) return 0;
if(b->curr >= b->ulength) return 0;
if(b->curr + sizeof(uint64_t) > b->ulength) return 0;
u = *((uint64_t *)(b->raw + b->curr));
b->curr += sizeof(uint64_t);
*o = ntohll(u);
return sizeof(uint64_t);
}
/* get raw data, pointer must be allocated with at least required length,
* will return size of ridden data
*/
uint32_t ndbuf_read_raw(ndbuf_t *b, void *o, uint32_t rlen)
{
if(!b || !o) return 0;
if(!rlen || !b->raw) return 0;
if(b->curr >= b->ulength) return 0;
if(b->curr + rlen > b->ulength) return 0;
memcpy(o, (const void*)b->raw + b->curr, rlen);
b->curr += rlen;
return rlen;
}
static int __rdb_grow(ndbuf_t *b, uint32_t len)
{
uint32_t rlen;
char *ne = NULL;
const struct ndbuf_memops *o = NULL;
size_t bs = b->blk_size;
if(!len) return -1;
if(b->rlength + len > NDBUF_MAXLENGTH) return -1;
if(b->flags & NDBUF_UCMO) o = b->mop;
rlen = len + (len%bs != 0 ? (bs - len%bs) : 0);
if(b->rlength + rlen > NDBUF_MAXLENGTH) rlen = len;
rlen += b->rlength;
if(o) ne = (char *)o->alloc(rlen);
else ne = malloc(rlen);
if(!ne) return -1;
if(b->flags & NDBUF_BURN) {
if(o) o->zero((void *)ne, rlen);
else memset(ne, 0, rlen);
}
memcpy(ne, b->raw, b->ulength);
if(o) {
if(b->flags & NDBUF_BURN) o->zero((void *)b->raw, b->rlength);
o->free((void *)b->raw);
} else {
if(b->flags & NDBUF_BURN) memset(b->raw, 0, b->rlength);
free(b->raw);
}
b->raw = ne;
b->rlength = rlen;
return 0;
}
/* write different types, should return the size of the
* written data, otherwise error occurs */
uint32_t ndbuf_write_u8(ndbuf_t *b, uint8_t u)
{
if(!b || !b->raw) return 0;
if(b->ulength == b->rlength) {
if(__rdb_grow(b, sizeof(uint8_t))) return 0;
}
*(uint8_t *)(b->raw + b->ulength) = u;
b->ulength += sizeof(uint8_t);
return sizeof(uint8_t);
}
uint32_t ndbuf_write_u16(ndbuf_t *b, uint16_t uu)
{
if(!b || !b->raw) return 0;
if(b->ulength + sizeof(uint16_t) >= b->rlength) {
if(__rdb_grow(b, sizeof(uint16_t))) return 0;
}
*(uint16_t *)(b->raw + b->ulength) = htons(uu);
b->ulength += sizeof(uint16_t);
return sizeof(uint16_t);
}
uint32_t ndbuf_write_u32(ndbuf_t *b, uint32_t uu)
{
if(!b || !b->raw) return 0;
if(b->ulength + sizeof(uint32_t) >= b->rlength) {
if(__rdb_grow(b, sizeof(uint32_t))) return 0;
}
*(uint32_t *)(b->raw + b->ulength) = htonl(uu);
b->ulength += sizeof(uint32_t);
return sizeof(uint32_t);
}
uint32_t ndbuf_write_u64(ndbuf_t *b, uint64_t uu)
{
if(!b || !b->raw) return 0;
if(b->ulength + sizeof(uint64_t) >= b->rlength) {
if(__rdb_grow(b, sizeof(uint64_t))) return 0;
}
*(uint64_t *)(b->raw + b->ulength) = ntohll(uu);
b->ulength += sizeof(uint64_t);
return sizeof(uint64_t);
}
static inline int __ndbuf_is_ro(ndbuf_t *b)
{
return (b->flags & NDBUF_RORB) ? 1 : 0;
}
static inline int __ndbuf_is_nrea(ndbuf_t *b)
{
return (b->flags & NDBUF_NREA) ? 1 : 0;
}
/* write raw data with the given length */
uint32_t ndbuf_write_raw(ndbuf_t *b, void *wi, uint32_t len)
{
if(!b || !b->raw) return 0;
if(!wi || !len) return 0;
if(__ndbuf_is_ro(b)) return 0; /* read only buffer */
if(b->ulength + len >= b->rlength) {
if(__ndbuf_is_nrea(b)) return 0; /* non reallocatable buffer */
if(__rdb_grow(b, len)) return 0;
}
memcpy((void *)b->raw + b->ulength, (const void *)wi, len);
b->ulength += len;
return len;
}
/* write raw data *before* existing data */
uint32_t ndbuf_write_raw_head(ndbuf_t *b, void *wi, uint32_t len)
{
char *ne;
const struct ndbuf_memops *o = NULL;
uint32_t rlen;
size_t bs = b->blk_size;
if(!b || !b->raw) return 0;
if(!wi || !len) return 0;
if(__ndbuf_is_ro(b)) return 0; /* read only buffer */
if(b->ulength + len > b->rlength) {
if(__ndbuf_is_nrea(b)) return 0; /* non reallocatable buffer */
/* allocate a new one and copy it right */
if(b->rlength + len > NDBUF_MAXLENGTH) return -1;
rlen = len + (len%bs != 0 ? (bs - len%bs) : 0);
if(b->rlength + rlen > NDBUF_MAXLENGTH) rlen = len;
rlen += b->rlength;
if(b->flags & NDBUF_UCMO) o = b->mop;
if(o) ne = (char *)o->alloc(rlen);
else ne = malloc(rlen);
if(!ne) return -1;
if(b->flags & NDBUF_BURN) {
if(o) o->zero((void *)ne, rlen);
else memset(ne, 0, rlen);
}
memcpy((void *)ne + len, b->raw, b->ulength);
if(o) {
if(b->flags & NDBUF_BURN) o->zero((void *)b->raw, b->rlength);
o->free((void *)b->raw);
} else {
if(b->flags & NDBUF_BURN) memset(b->raw, 0, b->rlength);
free(b->raw);
}
b->raw = ne;
b->rlength = rlen;
} else {
memmove((void *)b->raw + b->ulength, b->raw, b->ulength);
}
memcpy(b->raw, wi, len);
b->ulength += len;
return len;
}
/* parse */
#define __is_moless(x) ((x) & NDBUF_MOLS) ? 1 : 0
#define __is_usermo(x) ((x) & NDBUF_UCMO) ? 1 : 0
int ndbuf_escan_va(ndbuf_t *b, const char *fmt, int argc, va_list ap)
{
register uint32_t fo = b->flags;
register uint32_t len;
uint32_t clen;
va_list ap_copy;
union {
uint8_t *_u8;
uint16_t *_u16;
uint32_t *_u32;
uint64_t *_u64;
void **_dp;
char **_cstr;
ndbuf_t **_rdb;
} d;
const char *t, *last;
int r, count;
va_copy(ap_copy, ap);
for(t = fmt, count = 0; *t != '\0'; t++, count++) {
if(count > argc && argc != -1) {
va_end(ap_copy);
return EINVAL;
}
switch(*t) {
case 'b':
d._u8 = va_arg(ap, uint8_t *);
len = ndbuf_read_u8(b, d._u8);
r = (len == sizeof(uint8_t)) ? 0 : -1;
break;
case 'w':
d._u16 = va_arg(ap, uint16_t *);
len = ndbuf_read_u16(b, d._u16);
r = (len == sizeof(uint16_t)) ? 0 : -1;
break;
case 'd':
d._u32 = va_arg(ap, uint32_t *);
len = ndbuf_read_u32(b, d._u32);
r = (len == sizeof(uint32_t)) ? 0 : -1;
break;
case 'q':
d._u64 = va_arg(ap, uint64_t *);
len = ndbuf_read_u64(b, d._u64);
r = (len == sizeof(uint64_t)) ? 0 : -1;
break;
case 's':
d._cstr = va_arg(ap, char **);
*d._cstr = NULL;
len = ndbuf_read_u32(b, &clen);
if(len != sizeof(uint32_t)) {
__errrbread:
r = -1;
break;
}
/* FIXME: Document the following line in manpages %limits% */
if(clen > NDBUF_MAXLENGTH) goto __errrbread;
if(__is_moless(fo)) {
*d._cstr = b->raw + b->curr;
} else {
if(__is_usermo(fo)) *d._cstr = b->mop->alloc(clen + sizeof(char));
else *d._cstr = malloc(clen + sizeof(char));
if(*d._cstr == NULL) {
r = -ENOMEM;
break;
}
len = ndbuf_read_raw(b, *d._cstr, clen);
if(len != clen) {
free(*d._cstr);
goto __errrbread;
}
(*d._cstr)[len] = '\0';
d._cstr = NULL;
}
r = 0;
break;
case 'p':
clen = va_arg(ap, size_t);
d._dp = va_arg(ap, void **);
*d._dp = NULL;
count++;
if(__is_moless(fo)) {
*d._dp = b->raw + b->curr;
} else {
if(__is_usermo(fo)) *d._dp = b->mop->alloc(clen);
else *d._dp = malloc(clen);
if(*d._dp == NULL) {
r = -ENOMEM;
break;
}
len = ndbuf_read_raw(b, *d._dp, clen);
if(len != clen) {
free(*d._dp);
goto __errrbread;
}
}
d._dp = NULL;
r = 0;
break;
case 'P':
d._dp = va_arg(ap, void **);
*d._dp = NULL;
len = ndbuf_read_u32(b, &clen);
if(len != sizeof(uint32_t)) {
r = -1;
break;
}
if(__is_moless(fo)) {
*d._dp = b->raw + b->curr;
} else {
if(__is_usermo(fo)) *d._dp = b->mop->alloc(clen);
else *d._dp = malloc(clen);
if(*d._dp == NULL) {
r = -ENOMEM;
break;
}
len = ndbuf_read_raw(b, *d._dp, clen);
if(len != clen) {
free(*d._dp);
goto __errrbread;
}
}
d._dp = NULL;
r = 0;
break;
case 'R': /* FIXME: what about moless and user defined ops ? */
d._rdb = va_arg(ap, ndbuf_t **);
*d._rdb = NULL;
len = ndbuf_read_u32(b, &clen);
if(len != sizeof(uint32_t)) {
r = -1;
break;
}
/* allocate rdb and write to it */
if((*d._rdb = ndbuf_new_palloc(clen)) == NULL) {
r = -ENOMEM;
break;
} else ndbuf_setflags(*d._rdb, NDBUF_BURN);
len = ndbuf_read_raw(b, ndbuf_rdata(*d._rdb), clen);
if(len != clen) {
ndbuf_free(*d._dp);
goto __errrbread;
} else ndbuf_setlength(*d._rdb, clen);
d._rdb = NULL;
r = 0;
break;
}
if(r) break;
}
if(argc != -1 && argc != count) r = -EINVAL;
if(!r) {
clen = va_arg(ap, uint32_t);
if(clen != NDBUF_TERMINAT) {
if(argc == -1) r = -EINVAL;
else abort();
}
}
/* clean up all the stuff on error */
if(r) {
last = t;
for(t = fmt; t < last; ++t) {
switch(*t) {
case 'b':
case 'w':
case 'd':
case 'q':
(void)va_arg(ap_copy, void *);
break;
case 's':
d._cstr = va_arg(ap_copy, char **);
if(*d._cstr && !__is_moless(fo)) {
if(__is_usermo(fo)) {
b->mop->zero(*d._cstr, strlen(*d._cstr));
b->mop->free(*d._cstr);
} else {
memset(*d._cstr, 0, strlen(*d._cstr));
free(*d._cstr);
}
}
break;
case 'R':
d._rdb = va_arg(ap_copy, ndbuf_t **);
if(*d._rdb) ndbuf_free(*d._rdb);
break;
case 'p':
(void)va_arg(ap_copy, size_t);
case 'P':
d._dp = va_arg(ap_copy, void **);
if(*d._dp && !__is_moless(fo)) {
if(__is_usermo(fo)) b->mop->free(*d._dp);
else free(*d._dp);
}
break;
default:
(void)va_arg(ap_copy, void *);
break;
}
}
}
va_end(ap_copy);
return r;
}
int ndbuf_escan_wot(ndbuf_t *b, const char *fmt, int argc, ...)
{
va_list ap;
int r;
va_start(ap, argc);
r = ndbuf_escan_va(b, fmt, argc, ap);
va_end(ap);
return r;
}
/* print FIXME: TODO: add errno setting upon failure */
uint32_t ndbuf_print_va(ndbuf_t *b, const char *fmt, int argc, va_list ap)
{
const char *t;
char *cstr;
ndbuf_t *rdb;
union {
uint8_t _u8;
uint16_t _u16;
uint32_t _u32;
uint64_t _u64;
void *_dp;
} d;
uint32_t len = 0, clen;
int r, count;
if(__ndbuf_is_ro(b)) return 0; /* read only buffer */
for(t = fmt, count = 0; *t != '\0'; t++, count++) {
if(count > argc && argc != -1) return 0;
switch(*t) {
case 'b':
d._u8 = (uint8_t)va_arg(ap, unsigned int);
r = ndbuf_write_u8(b, d._u8);
if(r != sizeof(uint8_t)) return 0;
else len += r;
break;
case 'w':
d._u16 = (uint16_t)va_arg(ap, unsigned int);
r = ndbuf_write_u16(b, d._u16);
if(r != sizeof(uint16_t)) return 0;
else len += r;
break;
case 'd':
d._u32 = (uint32_t)va_arg(ap, uint32_t);
r = ndbuf_write_u32(b, d._u32);
if(r != sizeof(uint32_t)) return 0;
else len += r;
break;
case 'q':
d._u64 = (uint64_t)va_arg(ap, uint64_t);
r = ndbuf_write_u64(b, d._u64);
if(r != sizeof(uint64_t)) return 0;
else len += r;
break;
case 's':
cstr = (char *)va_arg(ap, char *);
clen = strlen(cstr);
r = ndbuf_write_u32(b, (uint32_t)clen);
if(r != sizeof(uint32_t)) return 0;
else len += r;
r = ndbuf_write_raw(b, cstr, clen);
if(r != clen) return 0;
else len += clen;
break;
case 'R':
rdb = (ndbuf_t *)va_arg(ap, ndbuf_t *);
clen = ndbuf_length(rdb);
r = ndbuf_write_u32(b, (uint32_t)clen);
if(r != sizeof(uint32_t)) return 0;
else len += r;
r = ndbuf_write_raw(b, ndbuf_rdata(rdb), (uint32_t)clen);
if(r != clen) return 0;
else len += clen;
break;
case 'P':
clen = va_arg(ap, size_t);
d._dp = va_arg(ap, void *);
count++;
r = ndbuf_write_u32(b, (uint32_t)clen);
if(r != sizeof(uint32_t)) return 0;
else len += r;
r = ndbuf_write_raw(b, d._dp, (uint32_t)clen);
if(r != clen) return 0;
else len += clen;
break;
case 'p':
clen = va_arg(ap, size_t);
d._dp = va_arg(ap, void *);
count++;
r = ndbuf_write_raw(b, d._dp, (uint32_t)clen);
if(r != clen) return 0;
else len += clen;
break;
default:
return 0;
break;
}
}
if(argc != count && argc != -1) return 0;
clen = va_arg(ap, uint32_t);
if(clen != NDBUF_TERMINAT) {
if(argc == -1) return 0;
else abort(); /* corruption */
}
return len;
}
uint32_t ndbuf_print_wot(ndbuf_t *b, const char *fmt, int argc, ...)
{
va_list ap;
uint32_t wrl;
va_start(ap, argc);
wrl = ndbuf_print_va(b, fmt, argc, ap);
va_end(ap);
return wrl;
}
/* misc */
/* returns length of used space in the buffer */
uint32_t ndbuf_length(ndbuf_t *b)
{
if(!b || !b->raw) return 0;
return b->ulength;
}
/* returns length of allocated space in the buffer */
uint32_t ndbuf_alength(ndbuf_t *b)
{
if(!b || !b->raw) return 0;
return b->rlength;
}
/* returns length of the left data to read */
uint32_t ndbuf_leftlength(ndbuf_t *b)
{
if(!b || !b->raw) return 0;
if(b->curr > b->ulength) return 0;
return b->ulength - b->curr;
}
/* reaturn a pointer to the raw data */
void *ndbuf_rdata(ndbuf_t *b)
{
if(!b || !b->raw) return NULL;
return (void *)b->raw;
}
/* return pointer to the data currently being read/write */
void *ndbuf_rdatacur(ndbuf_t *b)
{
if(!b || !b->raw) return NULL;
if(b->curr >= b->ulength) return NULL;
return (void *)(b->raw + b->curr);
}
/* reset current pointer */
void ndbuf_resetcur(ndbuf_t *b)
{
if(!b || b->raw) return;
else b->curr = 0;
return;
}
/* set flags to the raw buffer */
void ndbuf_setflags(ndbuf_t *b, int af)
{
if(!b) return;
if(((af & NDBUF_BURN) && (b->flags & NDBUF_UCMO)) && !b->mop->zero) return;
b->flags |= af;
return;
}
/* exchange flags for raw buff */
void ndbuf_exflags(ndbuf_t *b, int nf)
{
if(!b) return;
if(b->flags & NDBUF_UCMO) nf |= NDBUF_UCMO;
b->flags = nf;
return;
}
int ndbuf_setlength(ndbuf_t *b, uint32_t s)
{
if(!b) return EINVAL;
if(s > b->rlength) return EINVAL;
else b->ulength = s;
return 0;
}
/* compare buffers, returns 0 if equal */
int ndbuf_cmp(ndbuf_t *b1, ndbuf_t *b2)
{
int c = 0;
if(!b1 | !b2) return -1;
if((c = ndbuf_length(b1) - ndbuf_length(b2)) != 0) return c;
else c = memcmp((const void *)ndbuf_rdata(b1),
(const void *)ndbuf_rdata(b2),
ndbuf_length(b1));
return c;
}
/* let the buffer to use actually used bytes, not all allocated space
* will return 0 on success (or in case if it doesn't required),
* ENOMEM or other error if fails
* TODO: ? make this buffer non reallocable ?
*/
int ndbuf_memopt(ndbuf_t *b)
{
uint32_t len;
size_t bs = b->blk_size;
char *ne;
const struct ndbuf_memops *o = NULL;
if(!b || !b->raw) return EINVAL;
if((b->rlength - b->ulength) > bs) {
len = b->ulength +
(b->ulength%bs != 0 ? (bs - b->ulength%bs) : 0);
if(b->flags & NDBUF_UCMO) o = b->mop;
if(o) ne = (char *)o->alloc(len);
else ne = malloc(len);
if(!ne) return ENOMEM;
if(b->flags & NDBUF_BURN) {
if(o) o->zero((void *)ne, len);
else memset(ne, 0, len);
}
memcpy(ne, b->raw, b->ulength);
if(o) {
if(b->flags & NDBUF_BURN) o->zero((void *)b->raw, b->rlength);
o->free((void *)b->raw);
} else {
if(b->flags & NDBUF_BURN) memset(b->raw, 0, b->rlength);
free(b->raw);
}
b->raw = ne;
b->rlength = len;
}
return 0;
}
#undef DEFAULT_PREALLOC_SIZE