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-rw-r--r--sys/kern/subr_sbuf.c271
-rw-r--r--sys/sys/sbuf.h76
2 files changed, 347 insertions, 0 deletions
diff --git a/sys/kern/subr_sbuf.c b/sys/kern/subr_sbuf.c
new file mode 100644
index 000000000000..9e537a8fbf1a
--- /dev/null
+++ b/sys/kern/subr_sbuf.c
@@ -0,0 +1,271 @@
+/*-
+ * Copyright (c) 2000 Poul-Henning Kamp and Dag-Erling Co´dan Sm°rgrav
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer
+ * in this position and unchanged.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ * derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * $FreeBSD$
+ */
+
+#include <sys/param.h>
+#include <sys/kernel.h>
+#include <sys/malloc.h>
+#include <sys/sbuf.h>
+#include <sys/systm.h>
+
+#include <machine/stdarg.h>
+
+MALLOC_DEFINE(M_SBUF, "sbuf", "string buffers");
+
+#ifdef INVARIANTS
+static void
+assert_sbuf_integrity(struct sbuf *s)
+{
+ KASSERT(s != NULL,
+ (__FUNCTION__ " called with a NULL sbuf pointer"));
+ KASSERT(s->s_buf != NULL,
+ (__FUNCTION__ " called with unitialized or corrupt sbuf"));
+ KASSERT(s->s_len < s->s_size,
+ ("wrote past end of sbuf (%d >= %d)", s->s_len, s->s_size));
+}
+
+static void
+assert_sbuf_state(struct sbuf *s, int state)
+{
+ KASSERT((s->s_flags & SBUF_FINISHED) == state,
+ (__FUNCTION__ " called with %sfinished or corrupt sbuf",
+ (state ? "un" : "")));
+}
+#else
+#define assert_sbuf_integrity(s) do { } while (0)
+#define assert_sbuf_state(s, i) do { } while (0)
+#endif
+
+/*
+ * Initialize an sbuf.
+ * If buf is non-NULL, it points to a static or already-allocated string
+ * big enough to hold at least length characters.
+ */
+int
+sbuf_new(struct sbuf *s, char *buf, size_t length, int flags)
+{
+ KASSERT(flags == 0,
+ (__FUNCTION__ " called with non-zero flags"));
+ KASSERT(s != NULL,
+ (__FUNCTION__ " called with a NULL sbuf pointer"));
+
+ bzero(s, sizeof *s);
+ s->s_size = length;
+ if (buf) {
+ s->s_buf = buf;
+ return (0);
+ }
+ s->s_buf = malloc(s->s_size, M_SBUF, M_WAITOK);
+ if (s->s_buf == NULL)
+ return (-1);
+ SBUF_SETFLAG(s, SBUF_DYNAMIC);
+ return (0);
+}
+
+/*
+ * Set the sbuf's position to an arbitrary value
+ */
+int
+sbuf_setpos(struct sbuf *s, size_t pos)
+{
+ assert_sbuf_integrity(s);
+ assert_sbuf_state(s, 0);
+
+ KASSERT(pos >= 0,
+ ("attempt to seek to a negative position (%d)", pos));
+ KASSERT(pos < s->s_size,
+ ("attempt to seek past end of sbuf (%d >= %d)", pos, s->s_size));
+
+ if (pos < 0 || pos > s->s_len)
+ return (-1);
+ s->s_len = pos;
+ return (0);
+}
+
+/*
+ * Append a string to an sbuf.
+ */
+int
+sbuf_cat(struct sbuf *s, char *str)
+{
+ assert_sbuf_integrity(s);
+ assert_sbuf_state(s, 0);
+
+ if (SBUF_HASOVERFLOWED(s))
+ return (-1);
+
+ while (*str && SBUF_HASROOM(s))
+ s->s_buf[s->s_len++] = *str++;
+ if (*str) {
+ SBUF_SETFLAG(s, SBUF_OVERFLOWED);
+ return (-1);
+ }
+ return (0);
+}
+
+/*
+ * Copy a string into an sbuf.
+ */
+int
+sbuf_cpy(struct sbuf *s, char *str)
+{
+ assert_sbuf_integrity(s);
+ assert_sbuf_state(s, 0);
+
+ s->s_len = 0;
+ return (sbuf_cat(s, str));
+}
+
+/*
+ * PCHAR function for sbuf_printf()
+ */
+static void
+_sbuf_pchar(int c, void *v)
+{
+ struct sbuf *s = (struct sbuf *)v;
+
+ assert_sbuf_integrity(s);
+ assert_sbuf_state(s, 0);
+
+ if (SBUF_HASOVERFLOWED(s))
+ return;
+ if (SBUF_HASROOM(s))
+ s->s_buf[s->s_len++] = c;
+ else
+ SBUF_SETFLAG(s, SBUF_OVERFLOWED);
+}
+
+/*
+ * Format the given arguments and append the resulting string to an sbuf.
+ */
+int
+sbuf_printf(struct sbuf *s, char *fmt, ...)
+{
+ va_list ap;
+ size_t len;
+
+ assert_sbuf_integrity(s);
+ assert_sbuf_state(s, 0);
+
+ KASSERT(fmt != NULL,
+ (__FUNCTION__ " called with a NULL format string"));
+
+ if (SBUF_HASOVERFLOWED(s))
+ return (-1);
+
+ va_start(ap, fmt);
+ len = kvprintf(fmt, _sbuf_pchar, s, 10, ap);
+ va_end(ap);
+
+ KASSERT(s->s_len < s->s_size,
+ ("wrote past end of sbuf (%d >= %d)", s->s_len, s->s_size));
+
+ if (SBUF_HASOVERFLOWED(s))
+ return (-1);
+ return (0);
+}
+
+/*
+ * Append a character to an sbuf.
+ */
+int
+sbuf_putc(struct sbuf *s, int c)
+{
+ assert_sbuf_integrity(s);
+ assert_sbuf_state(s, 0);
+
+ if (SBUF_HASOVERFLOWED(s))
+ return (-1);
+
+ if (!SBUF_HASROOM(s)) {
+ SBUF_SETFLAG(s, SBUF_OVERFLOWED);
+ return (-1);
+ }
+ s->s_buf[s->s_len++] = c;
+ return (0);
+}
+
+/*
+ * Finish off an sbuf.
+ */
+int
+sbuf_finish(struct sbuf *s)
+{
+ assert_sbuf_integrity(s);
+ assert_sbuf_state(s, 0);
+
+ if (SBUF_HASOVERFLOWED(s))
+ return (-1);
+
+ s->s_buf[s->s_len++] = '\0';
+ SBUF_SETFLAG(s, SBUF_FINISHED);
+ return (0);
+}
+
+/*
+ * Return a pointer to the sbuf data.
+ */
+char *
+sbuf_data(struct sbuf *s)
+{
+ assert_sbuf_integrity(s);
+ assert_sbuf_state(s, SBUF_FINISHED);
+
+ if (SBUF_HASOVERFLOWED(s))
+ return (NULL);
+ return s->s_buf;
+}
+
+/*
+ * Return the length of the sbuf data.
+ */
+size_t
+sbuf_len(struct sbuf *s)
+{
+ assert_sbuf_integrity(s);
+ assert_sbuf_state(s, SBUF_FINISHED);
+
+ if (SBUF_HASOVERFLOWED(s))
+ return (0);
+ return s->s_len;
+}
+
+/*
+ * Clear an sbuf, free its buffer if necessary.
+ */
+void
+sbuf_delete(struct sbuf *s)
+{
+ assert_sbuf_integrity(s);
+ /* don't care if it's finished or not */
+
+ if (SBUF_ISDYNAMIC(s))
+ free(s->s_buf, M_SBUF);
+ bzero(s, sizeof *s);
+}
diff --git a/sys/sys/sbuf.h b/sys/sys/sbuf.h
new file mode 100644
index 000000000000..5995ec1c32b4
--- /dev/null
+++ b/sys/sys/sbuf.h
@@ -0,0 +1,76 @@
+/*-
+ * Copyright (c) 2000 Poul-Henning Kamp and Dag-Erling Co´dan Sm°rgrav
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer
+ * in this position and unchanged.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ * derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * $FreeBSD$
+ */
+
+#ifndef _SYS_SBUF_H_
+#define _SYS_SBUF_H_
+
+/*
+ * Structure definition
+ */
+struct sbuf {
+ char *s_buf; /* storage buffer */
+ struct sbuf *s_next; /* next in chain */
+ size_t s_size; /* size of storage buffer */
+ size_t s_len; /* current length of string */
+#define SBUF_AUTOEXTEND 0x00000001 /* automatically extend buffer */
+#define SBUF_DYNAMIC 0x00010000 /* s_buf must be freed */
+#define SBUF_FINISHED 0x00020000 /* set by sbuf_finish() */
+#define SBUF_OVERFLOWED 0x00040000 /* sbuf overflowed */
+ int s_flags; /* flags */
+};
+
+/*
+ * Predicates
+ */
+#define SBUF_ISDYNAMIC(s) ((s)->s_flags & SBUF_DYNAMIC)
+#define SBUF_ISFINISHED(s) ((s)->s_flags & SBUF_FINISHED)
+#define SBUF_HASOVERFLOWED(s) ((s)->s_flags & SBUF_OVERFLOWED)
+#define SBUF_HASROOM(s) ((s)->s_len < (s)->s_size - 1)
+
+/*
+ * Other macros
+ */
+#define SBUF_SETFLAG(s, f) do { (s)->s_flags |= (f); } while (0)
+
+/*
+ * API functions
+ */
+int sbuf_new(struct sbuf *s, char *buf, size_t length, int flags);
+int sbuf_setpos(struct sbuf *s, size_t pos);
+int sbuf_cat(struct sbuf *s, char *str);
+int sbuf_cpy(struct sbuf *s, char *str);
+int sbuf_printf(struct sbuf *s, char *fmt, ...);
+int sbuf_putc(struct sbuf *s, int c);
+int sbuf_finish(struct sbuf *s);
+char *sbuf_data(struct sbuf *s);
+size_t sbuf_len(struct sbuf *s);
+void sbuf_delete(struct sbuf *s);
+
+#endif