ndbuf_write_raw manual page has been added;

free allocated stuff via escan function.

ChangeLog

@@ -1,3 +1,9 @@
+0.0.2 (15-nov-2018)
+ * Added possibility to use user defined memory ops with:
+   ndbuf_t *ndbuf_new_wmops(const struct ndbuf_memops *, const size_t);
+ * Fixed bug with pkgconfig %VERSION% value
+
+
 0.0.1 (24-nov-2017)
  * initial version with all functions done
  * tired from reuse this code and ... now it's lib

Makefile.am

@@ -1,8 +1,9 @@
 ## Sample for libndbuf automaken stuff
-## (c) alex@vapaa.xyz
+## Distributed under GNU LGPL v2.1 or later
+## Originally written by Alexander Vdolainen <alex@vapaa.xyz> (c) 2017
 ## Process this file with automake to produce Makefile.in
 
-SUBDIRS = include
+SUBDIRS = include man
 
 clean-local:
 

NEWS

@@ -0,0 +1,2 @@
+NEWS template
+-------------

README

@@ -1,30 +1,28 @@
-libndbuf: Network designed buffer ops library
-----------------------------------------------
+libndbuf: Network-oriented buffer operations library
+----------------------------------------------------
 
-1. What the shit is that ?
-This is a quite small library to manipulate with binary packed buffers
-in a normal network manner (i.e. bigendian). It might be useful to
-apply for network packet creating/parsing.
-Anyway, originally this code was resided in my different other *small*
-projects - and i hate copy-paste -- well, that's why it gone to
-this quite small library.
+1. What is it?
+A small C library providing a simple API to read and write typed values
+to/from buffers with correct endianness handling.
 
-2. API
-Check out include directory...
-btw, might be later i will write manpages, but for now didn't see any
-sense for those effort.
-Generally speaking - all is quite simple - create ndbuf_t structure fill
-it in printf() style, read with sscanf() style, take raw data pointer and ...
-send it somewhere whatever bla bla - you get a point.
+2. Purpose
+Make parsing and building network packets easy and concise. The API is
+intended to act like a binary printf/scanf for packet fields.
+
+Example:
+
+Packet layout:
+<16-bit><8-bit><32-bit><raw data>
+
+Reading with a single call:
+ndbuf_escan(buf, "wbdR", &a16, &a8, &a32, &data_ptr)
+
+The same style is used to build packets.
 
 3. Future plans
-Fix bugs (but ... there are no bugs found, since this code was heavly used
-already, but ... report me if found).
-Write manpages (in my few projects those API is like a part of POSIX -
-still cannot remember all).
-Maybe will add a new functions (useful ones).
+ * Improve the API ergonomics (better support for preallocated buffers).
+ * Add convenience helpers and safer bounds checks.
+ * Possibly extend format specifiers and documentation.
 
 4. Contact
-That's simple -
-Email/XMPP: alex@vapaa.xyz
-
+Email: alex@vapaa.xyz

VERSION

@@ -1,2 +1,2 @@
-0.0.1
+0.0.2
 

configure.ac

@@ -16,4 +16,5 @@ AC_OUTPUT([
 Makefile
 libndbuf.pc
 include/Makefile
+man/Makefile
 ])

include/ndbuf/ndbuf.h

@@ -5,12 +5,12 @@
  * (c) Alexander Vdolainen 2016 <avdolainen@zoho.com>
  * (c) Alexander Vdolainen 2017 <alex@vapaa.xyz>
  *
- * libtbusd is free software: you can redistribute it and/or modify it
+ * 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.
  *
- * libtbusd is distributed in the hope that it will be useful, but
+ * 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.
@@ -27,16 +27,33 @@
 
 #define NDBUF_TERMINAT  0xdeadbeef
 
+/* List of supported flags: */
 #define NDBUF_BURN  (1 << 1)  /* burn buffer data before free */
 #define NDBUF_NREA  (1 << 2)  /* non reallocatable buffer */
+#define NDBUF_UCMO  (1 << 3)  /* user defined memops functions */
+#define NDBUF_RORB  (1 << 4)  /* read-only buffer */
+#define NDBUF_MOLS  (1 << 5)  /* "memory-ops"-less escan i.e. return
+                               * pointers to the raw buffer itself,
+                               *  instead of alloc/memcpy
+                               */
+
+struct ndbuf_memops {
+  void *(*alloc)(size_t);
+  uint32_t (*zero)(void *, size_t);
+  void (*free)(void *ptr);
+};
 
 typedef struct __rawdatabuffer_type {
   char *raw;
+  union {
+    void (*freebuf)(char *);
+    const struct ndbuf_memops *mop;
+  };
   uint32_t rlength; /* raw buffer allocated length */
   uint32_t ulength; /* length of used allocated space */
   uint32_t curr; /* cursor for read/write operations */
-  int flags;
-  void (*freebuf)(char *);
+  size_t blk_size;
+  uint32_t flags;
 } ndbuf_t;
 
 /* variadic macro workaround */
@@ -67,12 +84,15 @@ typedef struct __rawdatabuffer_type {
 /* allocate raw buffer with defaults preallocation */
 ndbuf_t *ndbuf_new(void);
 
-/* will do the same as ndbuf_new but will allocate given length */
+/* will do the same as ndbuf_new but will pre-allocate with the given length */
 ndbuf_t *ndbuf_new_palloc(uint32_t);
 
 /* create ndbuf from raw buffer */
 ndbuf_t *ndbuf_new_frombuf(char *buf, size_t buf_len, void (*freebuf)(char *));
 
+/* create a new buffer with user defined memops */
+ndbuf_t *ndbuf_new_wmops(const struct ndbuf_memops *, const size_t);
+
 /* free all allocated space and buffer itself */
 void ndbuf_free(ndbuf_t *);
 
@@ -158,4 +178,7 @@ int ndbuf_cmp(ndbuf_t *, ndbuf_t *);
  */
 int ndbuf_memopt(ndbuf_t *);
 
+/* free in a right way: freing allocated memory during escan */
+void ndbuf_free_item(ndbuf_t *b, void *ip, size_t is);
+
 #endif /* __NDBUF_H__ */

libndbuf.pc.in

@@ -7,7 +7,7 @@ includedir=@includedir@
 
 Name: libndbuf
 Description: Network designed binary buffer pack/unpack library
-Version: @LIBNDBUF_VERSION@
+Version: @VERSION@
 Requires: 
 Libs: -L${libdir} -lndbuf
 Cflags: -I${includedir}

man/Makefile.am

@@ -0,0 +1,5 @@
+man_MANS = ndbuf_new.3 ndbuf_new_palloc.3 ndbuf_new_wmops.3 ndbuf_new_frombuf.3 \
+	ndbuf_free.3 ndbuf_free_item.3 ndbuf_read_raw.3 ndbuf_read_u8.3 ndbuf_read_u16.3 \
+	ndbuf_read_u32.3 ndbuf_read_u64.3 ndbuf_write_raw.3 ndbuf_write_u8.3 ndbuf_write_u16.3 \
+	ndbuf_write_u32.3 ndbuf_write_u64.3 
+

man/ndbuf_free.3

@@ -0,0 +1 @@
+ndbuf_new.3

man/ndbuf_free_item.3

@@ -0,0 +1 @@
+ndbuf_new.3

man/ndbuf_new.3

@@ -0,0 +1,156 @@
+.TH NDBUF_NEW 3 "15 September 2018" "NDBUF" "Binary buffers lib manual"
+.SH NAME
+ndbuf_new, ndbuf_new_palloc, ndbuf_new_frombuf, ndbuf_new_wmops, ndbuf_free - allocate and free buffer structure
+.SH SYNOPSIS
+.B "#include <ndbuf/ndbuf.h>"
+.PP
+.nf
+ndbuf_t *ndbuf_new(void);
+ndbuf_t *ndbuf_new_palloc(uint32_t len);
+ndbuf_t *ndbuf_new_frombuf(char *buf, size_t buf_len,
+void (*freebuf)(char *));
+ndbuf_t *ndbuf_new_wmops(const struct ndbuf_memops *mops,
+const size_t block_size);
+void ndbuf_free(ndbuf_t *b);
+void ndbuf_free_item(ndbuf_t *b, void *item, size_t item_size);
+.PP
+struct ndbuf_memops {
+.br
+void *(*alloc)(size_t);
+.br
+uint32_t (*zero)(void *, size_t);
+.br
+void (*free)(void *);
+.br
+};
+.fi
+.SH DESCRIPTION
+The
+.B ndbuf_new
+family of functions create and initialize an
+.B ndbuf_t
+structure using different allocation and memory-operation options. These routines simplify handling raw network-oriented buffers while providing hooks for custom memory management and secure wiping.
+.PP
+
+.TP
+.B ndbuf_new()
+Allocate and return a newly initialized
+.B ndbuf_t
+using library defaults. A default memory chunk is preallocated. No special flags are set.
+.PP
+
+.TP
+.B ndbuf_new_palloc(uint32_t len)
+Allocate and return a new
+.B ndbuf_t
+with an initial buffer of the specified length (in bytes). Other defaults apply; no special flags are set.
+.PP
+
+.TP
+.B ndbuf_new_frombuf(char *buf, size_t buf_len, void (*freebuf)(char *))
+Create a
+.B ndbuf_t
+that uses the provided buffer pointer
+.I buf
+of length
+.I buf_len
+as its underlying storage. If
+.I freebuf
+is a valid pointer to the function, it will be called to free the buffer when the ndbuf is destroyed. The returned ndbuf will have the
+.B NDBUF_NREA
+flag set, indicating the buffer is non-reallocatable. See
+.BR ndbuf_setflags(3)
+for flag details.
+.PP
+
+.TP
+.B ndbuf_new_wmops(const struct ndbuf_memops *mops, const size_t block_size)
+Create a
+.B ndbuf_t
+that uses the caller-provided memory-operation callbacks and a custom block size. The
+.I mops
+structure must provide the following function pointers:
+.IP 
+.B alloc(size_t)
+Function to allocate a memory block of the given size.
+.IP
+.B zero(void *, size_t)
+Function to zero or overwrite a memory region; used when the
+.B NDBUF_BURN
+flag is set to securely erase memory.
+.IP
+.B free(void *)
+Free a previously allocated memory block.
+.IP
+No special flags are set by this call.
+.PP
+
+.TP
+.B ndbuf_free(ndbuf_t *b)
+Free the
+.I ndbuf_t
+structure and, unless prevented by flags or missing free callbacks, free the associated buffer data. The underlying buffer is not freed if:
+.IP
+The
+.B NDBUF_NREA
+flag is set and no
+.I freebuf
+callback was provided in
+.B ndbuf_new_frombuf().
+.IP
+The
+.B NDBUF_RORB
+flag is set.
+.PP
+
+.TP
+.B ndbuf_free_item(ndbuf_t *b, void item, size_t item_size)
+Free an item previously allocated via the library's escan function. If the
+.B NDBUF_BURN
+flag is set and
+.I item_size
+is non-zero, the buffer will be securely zeroed (via
+.B zero()
+or
+.B memset()
+) before being freed. This function uses the default memory ops unless custom ops were provided at creation.
+.SH RETURN VALUE
+On success the
+.B ndbuf_new
+family of functions returns a pointer to the newly created
+.B ndbuf_t.
+On failure they return
+.B NULL.
+No specific
+.I errno
+value is set by these functions.
+.SH ERRORS
+These functions return NULL on allocation or initialization failure. Callers should check the return value before use.
+.SH EXAMPLES
+.PP
+.nf
+/ Create a default buffer */
+ndbuf_t *b = ndbuf_new();
+if (!b) { / handle error */ }
+
+/* Create buffer from existing memory */
+char *buf = malloc(256);
+ndbuf_t *b2 = ndbuf_new_frombuf(buf, 256, free);
+
+/* Create buffer with custom memory ops */
+struct ndbuf_memops mops = { custom_alloc, custom_zero, custom_free };
+ndbuf_t *b3 = ndbuf_new_wmops(&mops, 4096);
+.fi
+.SH RATIONALE
+The
+.B ndbuf_new_wmops()
+function is useful for environments requiring special memory handling (for example, preventing pages from being swapped, using locked memory, or providing a custom zeroing routine to avoid compiler optimizations).
+.SH SEE ALSO
+.BR ndbuf_setflags(3),
+.BR ndbuf_escan(3)
+.SH COPYRIGHT
+This software licensed under GNU LGPL v2.1 or later. See COPYING for further details.
+.PP
+(c) Authors of libndbuf 2017-2018 <http://vapaa.xyz>
+.SH AUTHOR
+Alexander Vdolainen (alex@vapaa.xyz)

man/ndbuf_new_frombuf.3

@@ -0,0 +1 @@
+ndbuf_new.3

man/ndbuf_new_palloc.3

@@ -0,0 +1 @@
+ndbuf_new.3

man/ndbuf_new_wmops.3

@@ -0,0 +1 @@
+ndbuf_new.3

man/ndbuf_read_raw.3

@@ -0,0 +1,92 @@
+.TH NDBUF_READ_RAW 3 "15 September 2018" "NDBUF" "Binary buffers lib manual"
+.SH NAME
+ndbuf_read_u8, ndbuf_read_u16, ndbuf_read_u32, ndbuf_read_u64, 
+ndbuf_read_raw - read data of specified length and type
+.SH SYNOPSIS
+.B "#include <ndbuf/ndbuf.h>"
+.PP
+.nf
+uint32_t ndbuf_read_u8(ndbuf_t *b, uint8_t *val);
+uint32_t ndbuf_read_u16(ndbuf_t *b, uint16_t *val);
+uint32_t ndbuf_read_u32(ndbuf_t *b, uint32_t *val);
+uint32_t ndbuf_read_u64(ndbuf_t *b, uint64_t *val);
+uint32_t ndbuf_read_raw(ndbuf_t *b, void *dst, uint32_t len);
+.fi
+.SH DESCRIPTION
+The ndbuf_read_ family copies data from an
+.B ndbuf_t
+instance into caller-provided storage. On success each function returns the number of bytes read; on error it returns 0.
+
+.TP
+.B ndbuf_read_u8(ndbuf_t *b, uint8_t *val)
+Read one unsigned 8‑bit value from the current buffer position into
+.I val
+and advance the buffer cursor by one byte. Returned value is the number of bytes read (1) or 0 on error.
+
+.TP
+.B ndbuf_read_u16(ndbuf_t *b, uint16_t *val)
+Read one unsigned 16‑bit value, store it into
+.I val
+and advance the cursor by two bytes. Returns 2 on success or 0 on error.
+
+.TP
+.B ndbuf_read_u32(ndbuf_t *b, uint32_t *val)
+Read one unsigned 32‑bit value, store into
+.I val
+and advance the cursor by four bytes. Returns 4 on success or 0 on error.
+
+.TP
+.B ndbuf_read_u64(ndbuf_t *b, uint64_t *val)
+Read one unsigned 64‑bit value, store into
+.I val
+and advance the cursor by eight bytes. Returns 8 on success or 0 on error.
+
+.TP
+.B ndbuf_read_raw(ndbuf_t *b, void *dst, uint32_t len)
+Copy
+.I len
+bytes of raw data from the buffer to
+.I dst
+and advance the cursor by
+.I len. The caller must ensure
+.I dst
+points to memory at least
+.I len
+bytes long. Returns the number of bytes copied or 0 on error.
+.SH RETURN VALUE
+On success each function returns the number of bytes read. On error they return 0; no specific
+.I errno
+value is set.
+.SH ERRORS
+Functions return 0 when the requested read would exceed the available data, when
+.I b
+is NULL, or on other internal errors. Callers must validate the return value before using output data.
+.SH RATIONALE
+Use these functions when you need a local copy of numeric or raw data. For zero-copy parsing or formatted
+extraction consider the
+.BR ndbuf_escan(3)
+family instead.
+.SH EXAMPLES
+.PP
+.nf
+/* Read values from buffer */
+uint8_t  a8;
+uint16_t a16;
+uint32_t a32;
+if (ndbuf_read_u8(b, &a8) != 1) { /* handle error */ }
+if (ndbuf_read_u16(b, &a16) != 2) { /* handle error */ }
+if (ndbuf_read_u32(b, &a32) != 4) { /* handle error */ }
+
+/* Read raw payload */
+char payload[128];
+if (ndbuf_read_raw(b, payload, sizeof(payload)) != sizeof(payload)) { /* handle error */ }
+.fi
+.SH SEE ALSO
+.BR ndbuf_write_raw(3),
+.BR ndbuf_escan(3)
+.SH COPYRIGHT
+This software licensed under GNU LGPL v2.1 or later. See COPYING for further details.
+.PP
+(c) Authors of libndbuf 2017-2018 <http://vapaa.xyz>
+.SH AUTHOR
+Alexander Vdolainen (alex@vapaa.xyz)

man/ndbuf_read_u16.3

@@ -0,0 +1 @@
+ndbuf_read_raw.3

man/ndbuf_read_u32.3

@@ -0,0 +1 @@
+ndbuf_read_raw.3

man/ndbuf_read_u64.3

@@ -0,0 +1 @@
+ndbuf_read_raw.3

man/ndbuf_read_u8.3

@@ -0,0 +1 @@
+ndbuf_read_raw.3

man/ndbuf_write_raw.3

@@ -0,0 +1,77 @@
+.TH NDBUF_WRITE_RAW 3 "15 September 2018" "NDBUF" "Binary buffers lib manual"
+.SH NAME
+ndbuf_write_u8, ndbuf_write_u16, ndbuf_write_u32, ndbuf_write_u64, 
+ndbuf_write_raw - write data to the buffer of specified length and type
+.SH SYNOPSIS
+.B "#include <ndbuf/ndbuf.h>"
+.PP
+.nf
+uint32_t ndbuf_write_u8(ndbuf_t *b, uint8_t val);
+uint32_t ndbuf_write_u16(ndbuf_t *b, uint16_t val);
+uint32_t ndbuf_write_u32(ndbuf_t *b, uint32_t val);
+uint32_t ndbuf_write_u64(ndbuf_t *b, uint64_t val);
+uint32_t ndbuf_write_raw(ndbuf_t *b, void *src, uint32_t len);
+.fi
+.SH DESCRIPTION
+The ndbuf_write_ family writes data to an
+.B ndbuf_t
+instance from caller-provided storage. On success each function returns the number of bytes written; on error it returns 0.
+
+.TP
+.B ndbuf_write_u8(ndbuf_t *b, uint8_t val)
+Write one unsigned 8‑bit value to the current buffer position from
+.I val
+and advance the buffer cursor by one byte. Returned value is the number of bytes written (1) or 0 on error.
+
+.TP
+.B ndbuf_write_u16(ndbuf_t *b, uint16_t val)
+Writes one unsigned 16‑bit value, from
+.I val
+and advance the cursor by two bytes. Returns 2 on success or 0 on error.
+
+.TP
+.B ndbuf_write_u32(ndbuf_t *b, uint32_t val)
+Write one unsigned 32‑bit value, from
+.I val
+and advance the cursor by four bytes. Returns 4 on success or 0 on error.
+
+.TP
+.B ndbuf_write_u64(ndbuf_t *b, uint64_t val)
+Write one unsigned 64‑bit value, from
+.I val
+and advance the cursor by eight bytes. Returns 8 on success or 0 on error.
+
+.TP
+.B ndbuf_read_raw(ndbuf_t *b, void *dst, uint32_t len)
+Copy
+.I len
+from
+.I dst
+to the buffer and advance the cursor by
+.I len. The caller must ensure
+.I dst
+points to memory at least
+.I len
+bytes long. Returns the number of bytes copied or 0 on error.
+.SH RETURN VALUE
+On success each function returns the number of bytes read. On error they return 0; no specific
+.I errno
+value is set.
+.SH ERRORS
+Functions return 0 when the requested read would exceed the available data, when
+.I b
+is NULL, or on other internal errors. Callers must validate the return value before using output data.
+.SH RATIONALE
+None
+.SH EXAMPLES
+None
+.PP
+.SH SEE ALSO
+.BR ndbuf_read_raw(3),
+.BR ndbuf_print(3)
+.SH COPYRIGHT
+This software licensed under GNU LGPL v2.1 or later. See COPYING for further details.
+.PP
+(c) Authors of libndbuf 2017-2018 <http://vapaa.xyz>
+.SH AUTHOR
+Alexander Vdolainen (alex@vapaa.xyz)

man/ndbuf_write_u16.3

@@ -0,0 +1 @@
+ndbuf_write_raw.3

man/ndbuf_write_u32.3

@@ -0,0 +1 @@
+ndbuf_write_raw.3

man/ndbuf_write_u64.3

@@ -0,0 +1 @@
+ndbuf_write_raw.3

man/ndbuf_write_u8.3

@@ -0,0 +1 @@
+ndbuf_write_raw.3

ndbuf.c

@@ -2,14 +2,14 @@
  * Networking binary buffers pack/unpack library
  *
  * (c) Alexander Vdolainen 2016 <avdolainen@zoho.com>
- * (c) Alexander Vdolainen 2017 <alex@vapaa.xyz>
+ * (c) Alexander Vdolainen 2017, 2018 <alex@vapaa.xyz>
  *
- * libtbusd is free software: you can redistribute it and/or modify it
+ * 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.
  *
- * libtbusd is distributed in the hope that it will be useful, but
+ * 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.
@@ -34,7 +34,7 @@ static inline uint64_t ntohll(uint64_t n)
 #ifdef WORDS_BIGENDIAN
   return n;
 #else /* WORDS_BIGENDIAN */
-  return (((uint64_t)(n) << 56) | \
+  return (uint64_t)(((uint64_t)(n) << 56) |                      \
          (((uint64_t)(n) << 40) & 0xff000000000000ULL) | \
          (((uint64_t)(n) << 24) & 0xff0000000000ULL) | \
          (((uint64_t)(n) << 8)  & 0xff00000000ULL) | \
@@ -104,16 +104,51 @@ ndbuf_t *ndbuf_new_palloc(uint32_t 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_BURN) && b->raw)
-    memset(b->raw, 0, b->rlength);
+  if(b->flags & NDBUF_UCMO) o = b->mop;
 
-  if((b->flags & NDBUF_NREA) && b->freebuf) b->freebuf(b->raw);
-  else if(b->raw) free(b->raw);
+  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);
@@ -210,23 +245,37 @@ 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;
 
-  rlen = len +
-    (len%DEFAULT_PREALLOC_SIZE != 0 ? (DEFAULT_PREALLOC_SIZE - len%DEFAULT_PREALLOC_SIZE) : 0);
+  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(!(ne = malloc(rlen))) return -1;
+  if(o) ne = (char *)o->alloc(rlen);
+  else ne = malloc(rlen);
 
-  if(b->flags & NDBUF_BURN) memset(ne, 0, 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(b->flags & NDBUF_BURN) memset(b->raw, 0, b->rlength);
-  free(b->raw);
+  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;
 
@@ -287,12 +336,25 @@ uint32_t ndbuf_write_u64(ndbuf_t *b, uint64_t uu)
   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;
   }
 
@@ -306,27 +368,46 @@ uint32_t ndbuf_write_raw(ndbuf_t *b, void *wi, uint32_t len)
 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%DEFAULT_PREALLOC_SIZE != 0 ? (DEFAULT_PREALLOC_SIZE - len%DEFAULT_PREALLOC_SIZE) : 0);
+    rlen = len + (len%bs != 0 ? (bs - len%bs) : 0);
     if(b->rlength + rlen > NDBUF_MAXLENGTH) rlen = len;
 
     rlen += b->rlength;
-    if(!(ne = malloc(rlen))) return -1;
 
-    if(b->flags & NDBUF_BURN) memset(ne, 0, rlen);
+    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(b->flags & NDBUF_BURN) memset(b->raw, 0, b->rlength);
-    free(b->raw);
+    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 {
@@ -339,8 +420,14 @@ uint32_t ndbuf_write_raw_head(ndbuf_t *b, void *wi, uint32_t 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;
@@ -352,7 +439,6 @@ int ndbuf_escan_va(ndbuf_t *b, const char *fmt, int argc, va_list ap)
     ndbuf_t **_rdb;
   } d;
   const char *t, *last;
-  uint32_t len, clen;
   int r, count;
 
   va_copy(ap_copy, ap);
@@ -393,18 +479,26 @@ int ndbuf_escan_va(ndbuf_t *b, const char *fmt, int argc, va_list ap)
         r = -1;
         break;
       }
+      /* FIXME: Document the following line in manpages %limits% */
       if(clen > NDBUF_MAXLENGTH) goto __errrbread;
-      if((*d._cstr = malloc(clen + sizeof(char))) == NULL) {
-        r = -ENOMEM;
-        break;
+
+      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;
       }
-      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':
@@ -414,14 +508,20 @@ int ndbuf_escan_va(ndbuf_t *b, const char *fmt, int argc, va_list ap)
       *d._dp = NULL;
       count++;
 
-      if((*d._dp = malloc(clen)) == NULL) {
-        r = -ENOMEM;
-        break;
-      }
-      len = ndbuf_read_raw(b, *d._dp, clen);
-      if(len != clen) {
-        free(*d._dp);
-        goto __errrbread;
+      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;
@@ -435,19 +535,25 @@ int ndbuf_escan_va(ndbuf_t *b, const char *fmt, int argc, va_list ap)
         r = -1;
         break;
       }
-      if((*d._dp = malloc(clen)) == NULL) {
-        r = -ENOMEM;
-        break;
-      }
-      len = ndbuf_read_raw(b, *d._dp, clen);
-      if(len != clen) {
-        free(*d._dp);
-        goto __errrbread;
+      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':
+    case 'R': /* FIXME: what about moless and user defined ops ? */
       d._rdb = va_arg(ap, ndbuf_t **);
       *d._rdb = NULL;
 
@@ -498,9 +604,14 @@ int ndbuf_escan_va(ndbuf_t *b, const char *fmt, int argc, va_list ap)
         break;
       case 's':
         d._cstr = va_arg(ap_copy, char **);
-        if(*d._cstr) {
-          memset(*d._cstr, 0, strlen(*d._cstr));
-          free(*d._cstr);
+        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':
@@ -511,7 +622,10 @@ int ndbuf_escan_va(ndbuf_t *b, const char *fmt, int argc, va_list ap)
         (void)va_arg(ap_copy, size_t);
       case 'P':
         d._dp = va_arg(ap_copy, void **);
-        if(*d._dp) free(*d._dp);
+        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 *);
@@ -552,6 +666,8 @@ uint32_t ndbuf_print_va(ndbuf_t *b, const char *fmt, int argc, va_list ap)
   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) {
@@ -705,6 +821,8 @@ 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;
@@ -715,6 +833,8 @@ void ndbuf_exflags(ndbuf_t *b, int nf)
 {
   if(!b) return;
 
+  if(b->flags & NDBUF_UCMO) nf |= NDBUF_UCMO;
+
   b->flags = nf;
 
   return;
@@ -749,24 +869,43 @@ int ndbuf_cmp(ndbuf_t *b1, ndbuf_t *b2)
 /* 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) > DEFAULT_PREALLOC_SIZE) {
+  if((b->rlength - b->ulength) > bs) {
     len = b->ulength +
-      (b->ulength%DEFAULT_PREALLOC_SIZE != 0 ?
-       (DEFAULT_PREALLOC_SIZE - b->ulength%DEFAULT_PREALLOC_SIZE) : 0);
-    if(!(ne = malloc(len))) return ENOMEM;
+      (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);
+    }
 
-    if(b->flags & NDBUF_BURN) memset(ne, 0, len);
     memcpy(ne, b->raw, b->ulength);
-    if(b->flags & NDBUF_BURN) memset(b->raw, 0, b->ulength);
-    free(b->raw);
+
+    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;
   }
@@ -774,4 +913,21 @@ int ndbuf_memopt(ndbuf_t *b)
   return 0;
 }
 
+void ndbuf_free_item(ndbuf_t *b, void *ip, size_t is)
+{
+  if(!b || !ip) return;
+
+  if(__is_moless(b->flags)) return;
+
+  if(__is_usermo(b->flags)) {
+    if((b->flags & NDBUF_BURN) && (is > 0)) b->mop->zero(ip, is);
+    b->mop->free(ip);
+  } else {
+    if((b->flags & NDBUF_BURN) && (is > 0)) memset(ip, 0, is);
+    free(ip);
+  }
+
+  return;
+}
+
 #undef DEFAULT_PREALLOC_SIZE