--- /dev/null
+/* -*-c-*-
+ *
+ * $Id: buf.c,v 1.1 2003/10/11 21:02:33 mdw Exp $
+ *
+ * Buffer handling
+ *
+ * (c) 2001 Straylight/Edgeware
+ */
+
+/*----- Licensing notice --------------------------------------------------*
+ *
+ * This file is part of Catacomb.
+ *
+ * Catacomb 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.
+ *
+ * Catacomb 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 Catacomb; if not, write to the Free
+ * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
+ * MA 02111-1307, USA.
+ */
+
+/*----- Revision history --------------------------------------------------*
+ *
+ * $Log: buf.c,v $
+ * Revision 1.1 2003/10/11 21:02:33 mdw
+ * Import buf stuff from tripe.
+ *
+ * Revision 1.4 2001/06/19 22:09:54 mdw
+ * Expose interface, for use in the proxy.
+ *
+ * Revision 1.3 2001/03/03 12:06:48 mdw
+ * Use 16-bit lengths on MPs, since there's a packet limit of 64K anyway.
+ *
+ * Revision 1.2 2001/02/16 21:23:20 mdw
+ * Various minor changes. Check that MPs are in canonical form when
+ * loading.
+ *
+ * Revision 1.1 2001/02/03 20:26:37 mdw
+ * Initial checkin.
+ *
+ */
+
+/*----- Header files ------------------------------------------------------*/
+
+#include <string.h>
+
+#include <catacomb/mp.h>
+
+#include "buf.h"
+
+/*----- Main code ---------------------------------------------------------*/
+
+/* --- @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.
+ */
+
+void buf_init(buf *b, void *p, size_t sz)
+{
+ b->base = b->p = p;
+ b->limit = b->p + sz;
+ b->f = 0;
+}
+
+/* --- @buf_break@ --- *
+ *
+ * Arguments: @buf *b@ = pointer to a buffer block
+ *
+ * Returns: Some negative value.
+ *
+ * Use: Marks a buffer as broken.
+ */
+
+int buf_break(buf *b) { b->f |= BF_BROKEN; return (-1); }
+
+/* --- @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.
+ */
+
+void buf_flip(buf *b)
+{
+ b->limit = b->p;
+ b->p = b->base;
+}
+
+/* --- @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.
+ */
+
+int buf_ensure(buf *b, size_t sz) { return (BENSURE(b, 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.
+ */
+
+void *buf_get(buf *b, size_t sz)
+{
+ void *p;
+ if (BENSURE(b, sz))
+ return (0);
+ p = BCUR(b);
+ BSTEP(b, sz);
+ return (p);
+}
+
+/* --- @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
+ */
+
+int buf_put(buf *b, const void *p, size_t sz)
+{
+ if (BENSURE(b, sz))
+ return (-1);
+ memcpy(BCUR(b), p, sz);
+ BSTEP(b, sz);
+ return (0);
+}
+
+/* --- @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.
+ */
+
+int buf_getbyte(buf *b)
+{
+ if (BENSURE(b, 1))
+ return (-1);
+ return (*b->p++);
+}
+
+/* --- @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.
+ */
+
+int buf_putbyte(buf *b, int ch)
+{
+ if (BENSURE(b, 1))
+ return (-1);
+ *b->p++ = ch;
+ return (0);
+}
+
+/* --- @buf_getu16@ --- *
+ *
+ * Arguments: @buf *b@ = pointer to a buffer block
+ * @uint16 *w@ = where to put the word
+ *
+ * Returns: Zero if OK, or nonzero if there wasn't a word there.
+ *
+ * Use: Gets a 16-bit word from a buffer.
+ */
+
+int buf_getu16(buf *b, uint16 *w)
+{
+ if (BENSURE(b, 2))
+ return (-1);
+ *w = LOAD16(b->p);
+ BSTEP(b, 2);
+ return (0);
+}
+
+/* --- @buf_putu16@ --- *
+ *
+ * Arguments: @buf *b@ = pointer to a buffer block
+ * @uint16 w@ = word to write
+ *
+ * Returns: Zero if OK, nonzero if there wasn't enough space.
+ *
+ * Use: Puts a 16-but word in a buffer.
+ */
+
+int buf_putu16(buf *b, uint16 w)
+{
+ if (BENSURE(b, 2))
+ return (-1);
+ STORE16(b->p, w);
+ BSTEP(b, 2);
+ return (0);
+}
+
+/* --- @buf_getu32@ --- *
+ *
+ * Arguments: @buf *b@ = pointer to a buffer block
+ * @uint32 *w@ = where to put the word
+ *
+ * Returns: Zero if OK, or nonzero if there wasn't a word there.
+ *
+ * Use: Gets a 32-bit word from a buffer.
+ */
+
+int buf_getu32(buf *b, uint32 *w)
+{
+ if (BENSURE(b, 4))
+ return (-1);
+ *w = LOAD32(b->p);
+ BSTEP(b, 4);
+ return (0);
+}
+
+/* --- @buf_putu32@ --- *
+ *
+ * Arguments: @buf *b@ = pointer to a buffer block
+ * @uint32 w@ = word to write
+ *
+ * Returns: Zero if OK, nonzero if there wasn't enough space.
+ *
+ * Use: Puts a 32-but word in a buffer.
+ */
+
+int buf_putu32(buf *b, uint32 w)
+{
+ if (BENSURE(b, 4))
+ return (-1);
+ STORE32(b->p, w);
+ BSTEP(b, 4);
+ return (0);
+}
+
+/* --- @buf_getmp@ --- *
+ *
+ * Arguments: @buf *b@ = pointer to a buffer block
+ *
+ * Returns: A multiprecision integer, or null if there wasn't one there.
+ *
+ * Use: Gets a multiprecision integer from a buffer.
+ */
+
+mp *buf_getmp(buf *b)
+{
+ uint16 sz;
+ mp *m;
+ if (buf_getu16(b, &sz) || buf_ensure(b, sz))
+ return (0);
+ m = mp_loadb(MP_NEW, BCUR(b), sz);
+ if (mp_octets(m) != sz) {
+ mp_drop(m);
+ return (0);
+ }
+ BSTEP(b, sz);
+ return (m);
+}
+
+/* --- @buf_putmp@ --- *
+ *
+ * Arguments: @buf *b@ = pointer to a buffer block
+ * @mp *m@ = a multiprecision integer
+ *
+ * Returns: Zero if it worked, nonzero if there wasn't enough space.
+ *
+ * Use: Puts a multiprecision integer to a buffer.
+ */
+
+int buf_putmp(buf *b, mp *m)
+{
+ size_t sz = mp_octets(m);
+ assert(sz < MASK16);
+ if (buf_putu16(b, sz) || buf_ensure(b, sz))
+ return (-1);
+ mp_storeb(m, BCUR(b), sz);
+ BSTEP(b, sz);
+ return (0);
+}
+
+/*----- That's all, folks -------------------------------------------------*/