--- /dev/null
+/* -*-c-*-
+ *
+ * Reading and writing packet buffers
+ *
+ * (c) 2001 Straylight/Edgeware
+ */
+
+/*----- Licensing notice --------------------------------------------------*
+ *
+ * This file is part of the mLib utilities library.
+ *
+ * mLib is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Library General Public License as
+ * published by the Free Software Foundation; either version 2 of the
+ * License, or (at your option) any later version.
+ *
+ * mLib 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 Library General Public License for more details.
+ *
+ * You should have received a copy of the GNU Library General Public
+ * License along with mLib; if not, write to the Free
+ * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
+ * MA 02111-1307, USA.
+ */
+
+#ifndef MLIB_BUF_H
+#define MLIB_BUF_H
+
+#ifdef __cplusplus
+ extern "C" {
+#endif
+
+/*----- Header files ------------------------------------------------------*/
+
+#include <stddef.h>
+
+#ifndef MLIB_BITS_H
+# include "bits.h"
+#endif
+
+#ifndef MLIB_DSTR_H
+# include "dstr.h"
+#endif
+
+/*----- Data structures ---------------------------------------------------*/
+
+/* --- Buffers --- *
+ *
+ * Buffers provide a simple stream-like interface for building and parsing
+ * packets.
+ */
+
+typedef struct buf {
+ octet *base, *p, *limit; /* Pointers to the buffer */
+ unsigned f; /* Various flags */
+} buf;
+
+#define BF_BROKEN 1u /* Buffer is broken */
+
+/*----- Useful macros -----------------------------------------------------*/
+
+#define BBASE(b) ((b)->base)
+#define BLIM(b) ((b)->limit)
+#define BCUR(b) ((b)->p)
+#define BSZ(b) ((b)->limit - (b)->base)
+#define BLEN(b) ((b)->p - (b)->base)
+#define BLEFT(b) ((b)->limit - (b)->p)
+#define BSTEP(b, sz) ((b)->p += (sz))
+#define BBAD(b) ((b)->f & BF_BROKEN)
+#define BOK(b) (!BBAD(b))
+
+#define BENSURE(b, sz) \
+ (BBAD(b) ? -1 : (sz) > BLEFT(b) ? (b)->f |= BF_BROKEN, -1 : 0)
+
+#define BUF_DOSUFFIXES(_) DOUINTCONV(_) _(z, z, z)
+
+/*----- Functions provided ------------------------------------------------*/
+
+/* --- @buf_init@ --- *
+ *
+ * Arguments: @buf *b@ = pointer to a buffer block
+ * @void *p@ = pointer to a buffer
+ * @size_t sz@ = size of the buffer
+ *
+ * Returns: ---
+ *
+ * Use: Initializes the buffer block appropriately.
+ */
+
+extern void buf_init(buf */*b*/, void */*p*/, size_t /*sz*/);
+
+/* --- @buf_break@ --- *
+ *
+ * Arguments: @buf *b@ = pointer to a buffer block
+ *
+ * Returns: Some negative value.
+ *
+ * Use: Marks a buffer as broken.
+ */
+
+extern int buf_break(buf */*b*/);
+
+/* --- @buf_flip@ --- *
+ *
+ * Arguments: @buf *b@ = pointer to a buffer block
+ *
+ * Returns: ---
+ *
+ * Use: Flips a buffer so that if you've just been writing to it,
+ * you can now read from the bit you've written.
+ */
+
+extern void buf_flip(buf */*b*/);
+
+/* --- @buf_ensure@ --- *
+ *
+ * Arguments: @buf *b@ = pointer to a buffer block
+ * @size_t sz@ = size of data wanted
+ *
+ * Returns: Zero if it worked, nonzero if there wasn't enough space.
+ *
+ * Use: Ensures that there are @sz@ bytes still in the buffer.
+ */
+
+extern int buf_ensure(buf */*b*/, size_t /*sz*/);
+
+/* --- @buf_get@ --- *
+ *
+ * Arguments: @buf *b@ = pointer to a buffer block
+ * @size_t sz@ = size of the buffer
+ *
+ * Returns: Pointer to the place in the buffer.
+ *
+ * Use: Reserves a space in the buffer of the requested size, and
+ * returns its start address.
+ */
+
+extern void *buf_get(buf */*b*/, size_t /*sz*/);
+
+/* --- @buf_put@ --- *
+ *
+ * Arguments: @buf *b@ = pointer to a buffer block
+ * @const void *p@ = pointer to a buffer
+ * @size_t sz@ = size of the buffer
+ *
+ * Returns: Zero if it worked, nonzero if there wasn't enough space.
+ *
+ * Use: Fetches data from some place and puts it in the buffer
+ */
+
+extern int buf_put(buf */*b*/, const void */*p*/, size_t /*sz*/);
+
+/* --- @buf_getbyte@ --- *
+ *
+ * Arguments: @buf *b@ = pointer to a buffer block
+ *
+ * Returns: A byte, or less than zero if there wasn't a byte there.
+ *
+ * Use: Gets a single byte from a buffer.
+ */
+
+extern int buf_getbyte(buf */*b*/);
+
+/* --- @buf_putbyte@ --- *
+ *
+ * Arguments: @buf *b@ = pointer to a buffer block
+ * @int ch@ = byte to write
+ *
+ * Returns: Zero if OK, nonzero if there wasn't enough space.
+ *
+ * Use: Puts a single byte in a buffer.
+ */
+
+extern int buf_putbyte(buf */*b*/, int /*ch*/);
+
+/* --- @buf_getu{8,{16,24,32,64}{,l,b}}@ --- *
+ *
+ * Arguments: @buf *b@ = pointer to a buffer block
+ * @uintSZ *w@ = where to put the word
+ *
+ * Returns: Zero if OK, or nonzero if there wasn't a word there.
+ *
+ * Use: Gets a word of appropriate size and order from a buffer.
+ */
+
+#define BUF_DECL_GETU_(n, W, w) \
+ extern int buf_getu##w(buf */*b*/, uint##n */*w*/);
+DOUINTCONV(BUF_DECL_GETU_)
+
+/* --- @buf_putu{8,{16,24,32,64}{,l,b}}@ --- *
+ *
+ * Arguments: @buf *b@ = pointer to a buffer block
+ * @uintSZ w@ = word to write
+ *
+ * Returns: Zero if OK, or nonzero if there wasn't enough space
+ *
+ * Use: Puts a word into a buffer with appropriate size and order.
+ */
+
+#define BUF_DECL_PUTU_(n, W, w) \
+ extern int buf_putu##w(buf */*b*/, uint##n /*w*/);
+DOUINTCONV(BUF_DECL_PUTU_)
+
+/* --- @buf_getmem{8,{16,24,32,64}{,l,b},z} --- *
+ *
+ * Arguments: @buf *b@ = pointer to a buffer block
+ * @size_t *nn@ = where to put the length
+ *
+ * Returns: Pointer to the buffer data, or null.
+ *
+ * Use: Gets a chunk of memory from a buffer. The suffix is the
+ * width and byte order of the length; @z@ means null-
+ * terminated.
+ */
+
+#define BUF_DECL_GETMEM_(n, W, w) \
+ extern void *buf_getmem##w(buf */*b*/, size_t */*nn*/);
+BUF_DOSUFFIXES(BUF_DECL_GETMEM_)
+
+/* --- @buf_putmem{8,{16,24,32,64}{,l,b},z} --- *
+ *
+ * Arguments: @buf *b@ = pointer to a buffer block
+ * @const void *p@ = pointer to data to write
+ * @size_t n@ = length to write
+ *
+ * Returns: Zero if OK, nonzero if there wasn't enough space.
+ *
+ * Use: Writes a chunk of data to a buffer. The suffix is the
+ * width and byte order of the length; @z@ means null-
+ * terminated.
+ */
+
+#define BUF_DECL_PUTMEM_(n, W, w) \
+ extern int buf_putmem##w(buf */*b*/, const void */*p*/, size_t /*nn*/);
+BUF_DOSUFFIXES(BUF_DECL_PUTMEM_)
+
+/* --- @buf_getbuf{8,{16,24,32,64}{,l,b},z} --- *
+ *
+ * Arguments: @buf *b@ = pointer to a buffer block
+ * @buf *bb@ = where to put the result
+ *
+ * Returns: Zero if it worked, nonzero if there wasn't enough space.
+ *
+ * Use: Gets a block of data from a buffer, and writes its bounds to
+ * another buffer.
+ */
+
+#define BUF_DECL_GETBUF_(n, W, w) \
+ extern int buf_getbuf##w(buf */*b*/, buf */*bb*/);
+BUF_DOSUFFIXES(BUF_DECL_GETBUF_)
+
+/* --- @buf_putbuf{8,{16,24,32,64}{,l,b},z} --- *
+ *
+ * Arguments: @buf *b@ = pointer to a buffer block
+ * @buf *bb@ = buffer to write
+ *
+ * Returns: Zero if it worked, nonzero if there wasn't enough space.
+ *
+ * Use: Puts the contents of a buffer to a buffer.
+ */
+
+#define BUF_DECL_PUTBUF_(n, W, w) \
+ extern int buf_putbuf##w(buf */*b*/, buf */*bb*/);
+BUF_DOSUFFIXES(BUF_DECL_PUTBUF_)
+
+/* --- @buf_getdstr{8,{16,24,32,64}{,l,b},z} --- *
+ *
+ * Arguments: @buf *b@ = pointer to a buffer block
+ * @dstr *d@ = where to put the result
+ *
+ * Returns: Zero if it worked, nonzero if there wasn't enough space.
+ *
+ * Use: Gets a block of data from a buffer, and writes its contents
+ * to a string.
+ */
+
+#define BUF_DECL_GETDSTR_(n, W, w) \
+ extern int buf_getdstr##w(buf */*b*/, dstr */*d*/);
+BUF_DOSUFFIXES(BUF_DECL_GETDSTR_)
+
+/* --- @buf_putdstr{8,{16,24,32,64}{,l,b},z} --- *
+ *
+ * Arguments: @buf *b@ = pointer to a buffer block
+ * @dstr *d@ = string to write
+ *
+ * Returns: Zero if it worked, nonzero if there wasn't enough space.
+ *
+ * Use: Puts a dynamic string to a buffer.
+ */
+
+#define BUF_DECL_PUTDSTR_(n, W, w) \
+ extern int buf_putdstr##w(buf */*b*/, dstr */*d*/);
+BUF_DOSUFFIXES(BUF_DECL_PUTDSTR_)
+
+/* --- @buf_putstr{8,{16,24,32,64}{,l,b},z} --- *
+ *
+ * Arguments: @buf *b@ = pointer to a buffer block
+ * @const char *p@ = string to write
+ *
+ * Returns: Zero if it worked, nonzero if there wasn't enough space.
+ *
+ * Use: Puts a null-terminated string to a buffer.
+ */
+
+#define BUF_DECL_PUTSTR_(n, W, w) \
+ extern int buf_putstr##w(buf */*b*/, const char */*p*/);
+BUF_DOSUFFIXES(BUF_DECL_PUTSTR_)
+
+/*----- That's all, folks -------------------------------------------------*/
+
+#ifdef __cplusplus
+ }
+#endif
+
+#endif
~mdw / mLib / blobdiff