--- /dev/null
+/* -*-c-*-
+ *
+ * Buffer handling
+ *
+ * (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.
+ */
+
+/*----- Header files ------------------------------------------------------*/
+
+#include <assert.h>
+#include <string.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_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_GETU_(n, W, w) \
+ int buf_getu##w(buf *b, uint##n *ww) \
+ { \
+ if (BENSURE(b, SZ_##W)) return (-1); \
+ *ww = LOAD##W(b->p); \
+ BSTEP(b, SZ_##W); \
+ return (0); \
+ }
+DOUINTCONV(BUF_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_PUTU_(n, W, w) \
+ int buf_putu##w(buf *b, uint##n ww) \
+ { \
+ if (BENSURE(b, SZ_##W)) return (-1); \
+ STORE##W(b->p, ww); \
+ BSTEP(b, SZ_##W); \
+ return (0); \
+ }
+DOUINTCONV(BUF_PUTU_)
+
+/* --- @findz@ --- *
+ *
+ * Arguments: @buf *b@ = pointer to a buffer block
+ * @size_t *nn@ = where to put the length
+ *
+ * Returns: Zero if OK, nonzero if there wasn't a null byte to be found.
+ *
+ * Use: Finds a terminating null byte. The length includes this
+ * terminator.
+ */
+
+static int findz(buf *b, size_t *nn)
+{
+ octet *p;
+
+ if ((p = memchr(BCUR(b), 0, BLEFT(b))) == 0) {
+ buf_break(b);
+ return (-1);
+ }
+ *nn = p - BCUR(b) + 1;
+ return (0);
+}
+
+/* --- @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_GETMEM_(n, W, w) \
+ void *buf_getmem##w(buf *b, size_t *nn) \
+ { \
+ uint##n sz; \
+ if (buf_getu##w(b, &sz)) return (0); \
+ *nn = sz; \
+ return (buf_get(b, sz)); \
+ }
+DOUINTCONV(BUF_GETMEM_)
+
+void *buf_getmemz(buf *b, size_t *nn)
+{
+ if (findz(b, nn)) return (0);
+ return (buf_get(b, *nn));
+}
+
+/* --- @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_PUTMEM_(n, W, w) \
+ int buf_putmem##w(buf *b, const void *p, size_t sz) \
+ { \
+ assert(sz <= MASK##W); \
+ if (buf_putu##w(b, sz) || buf_put(b, p, sz)) \
+ return (-1); \
+ return (0); \
+ }
+DOUINTCONV(BUF_PUTMEM_)
+
+int buf_putmemz(buf *b, const void *p, size_t n)
+{
+ octet *q;
+
+ assert(!memchr(p, 0, n));
+ if ((q = buf_get(b, n + 1)) == 0)
+ return (-1);
+ memcpy(q, p, n);
+ q[n] = 0;
+ return (0);
+}
+
+/* --- @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_GETBUF_(n, W, w) \
+ int buf_getbuf##w(buf *b, buf *bb) \
+ { \
+ void *p; \
+ size_t sz; \
+ \
+ if ((p = buf_getmem##w(b, &sz)) == 0) \
+ return (-1); \
+ buf_init(bb, p, sz); \
+ return (0); \
+ }
+BUF_DOSUFFIXES(BUF_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_PUTBUF_(n, W, w) \
+ int buf_putbuf##w(buf *b, buf *bb) \
+ { return (buf_putmem##w(b, BBASE(bb), BLEN(bb))); }
+BUF_DOSUFFIXES(BUF_PUTBUF_)
+
+/* --- @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_PUTSTR_(n, W, w) \
+ int buf_putstr##w(buf *b, const char *p) \
+ { return (buf_putmem##w(b, p, strlen(p))); }
+BUF_DOSUFFIXES(BUF_PUTSTR_)
+
+/*----- That's all, folks -------------------------------------------------*/
~mdw / mLib / blobdiff