/*
- * Copyright (c) 2008, 2009 Nicira Networks.
+ * Copyright (c) 2008, 2009, 2010 Nicira Networks.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
#include <assert.h>
#include <stdlib.h>
#include <string.h>
+#include "dynamic-string.h"
#include "util.h"
/* Initializes 'b' as an empty ofpbuf that contains the 'allocated' bytes of
b->size = 0;
b->l2 = b->l3 = b->l4 = b->l7 = NULL;
b->next = NULL;
- b->private = NULL;
+ b->private_p = NULL;
}
/* Initializes 'b' as an empty ofpbuf with an initial capacity of 'size'
/* Frees memory that 'b' points to. */
void
-ofpbuf_uninit(struct ofpbuf *b)
+ofpbuf_uninit(struct ofpbuf *b)
{
if (b) {
free(b->base);
return b;
}
+/* Creates and returns a new ofpbuf with an initial capacity of 'size +
+ * headroom' bytes, reserving the first 'headroom' bytes as headroom. */
+struct ofpbuf *
+ofpbuf_new_with_headroom(size_t size, size_t headroom)
+{
+ struct ofpbuf *b = ofpbuf_new(size + headroom);
+ ofpbuf_reserve(b, headroom);
+ return b;
+}
+
struct ofpbuf *
ofpbuf_clone(const struct ofpbuf *buffer)
{
return ofpbuf_clone_data(buffer->data, buffer->size);
}
+/* Creates and returns a new ofpbuf whose data are copied from 'buffer'. The
+ * returned ofpbuf will additionally have 'headroom' bytes of headroom. */
+struct ofpbuf *
+ofpbuf_clone_with_headroom(const struct ofpbuf *buffer, size_t headroom)
+{
+ struct ofpbuf *b = ofpbuf_new_with_headroom(buffer->size, headroom);
+ ofpbuf_put(b, buffer->data, buffer->size);
+ return b;
+}
+
struct ofpbuf *
ofpbuf_clone_data(const void *data, size_t size)
{
/* Frees memory that 'b' points to, as well as 'b' itself. */
void
-ofpbuf_delete(struct ofpbuf *b)
+ofpbuf_delete(struct ofpbuf *b)
{
if (b) {
ofpbuf_uninit(b);
* commonly, the data in a ofpbuf is at its beginning, and thus the ofpbuf's
* headroom is 0.) */
size_t
-ofpbuf_headroom(struct ofpbuf *b)
+ofpbuf_headroom(const struct ofpbuf *b)
{
return (char*)b->data - (char*)b->base;
}
/* Returns the number of bytes that may be appended to the tail end of ofpbuf
* 'b' before the ofpbuf must be reallocated. */
size_t
-ofpbuf_tailroom(struct ofpbuf *b)
+ofpbuf_tailroom(const struct ofpbuf *b)
{
return (char*)ofpbuf_end(b) - (char*)ofpbuf_tail(b);
}
-/* Ensures that 'b' has room for at least 'size' bytes at its tail end,
- * reallocating and copying its data if necessary. */
-void
-ofpbuf_prealloc_tailroom(struct ofpbuf *b, size_t size)
+/* Changes 'b->base' to 'new_base' and adjusts all of 'b''s internal pointers
+ * to reflect the change. */
+static void
+ofpbuf_rebase__(struct ofpbuf *b, void *new_base)
{
- if (size > ofpbuf_tailroom(b)) {
- size_t new_allocated = b->allocated + MAX(size, 64);
- void *new_base = xmalloc(new_allocated);
+ if (b->base != new_base) {
uintptr_t base_delta = (char*)new_base - (char*)b->base;
- memcpy(new_base, b->base, b->allocated);
- free(b->base);
b->base = new_base;
- b->allocated = new_allocated;
b->data = (char*)b->data + base_delta;
if (b->l2) {
b->l2 = (char*)b->l2 + base_delta;
}
}
+/* Reallocates 'b' so that it has exactly 'new_tailroom' bytes of tailroom. */
+static void
+ofpbuf_resize_tailroom__(struct ofpbuf *b, size_t new_tailroom)
+{
+ b->allocated = ofpbuf_headroom(b) + b->size + new_tailroom;
+ ofpbuf_rebase__(b, xrealloc(b->base, b->allocated));
+}
+
+/* Ensures that 'b' has room for at least 'size' bytes at its tail end,
+ * reallocating and copying its data if necessary. Its headroom, if any, is
+ * preserved. */
void
-ofpbuf_prealloc_headroom(struct ofpbuf *b, size_t size)
+ofpbuf_prealloc_tailroom(struct ofpbuf *b, size_t size)
+{
+ if (size > ofpbuf_tailroom(b)) {
+ ofpbuf_resize_tailroom__(b, MAX(size, 64));
+ }
+}
+
+void
+ofpbuf_prealloc_headroom(struct ofpbuf *b, size_t size)
{
assert(size <= ofpbuf_headroom(b));
}
-/* Trims the size of 'b' to fit its actual content. */
+/* Trims the size of 'b' to fit its actual content, reducing its tailroom to
+ * 0. Its headroom, if any, is preserved. */
void
ofpbuf_trim(struct ofpbuf *b)
{
- /* XXX These could be supported, but the current client doesn't care. */
- assert(b->data == b->base);
- assert(b->l2 == NULL && b->l3 == NULL && b->l4 == NULL && b->l7 == NULL);
- if (b->allocated > b->size) {
- b->base = b->data = xrealloc(b->base, b->size);
- b->allocated = b->size;
+ if (ofpbuf_tailroom(b) > 0) {
+ ofpbuf_resize_tailroom__(b, 0);
}
}
* copying its data if necessary. Returns a pointer to the first byte of the
* new data, which is left uninitialized. */
void *
-ofpbuf_put_uninit(struct ofpbuf *b, size_t size)
+ofpbuf_put_uninit(struct ofpbuf *b, size_t size)
{
void *p;
ofpbuf_prealloc_tailroom(b, size);
* is reallocated and copied if necessary. Returns a pointer to the first
* byte of the data's location in the ofpbuf. */
void *
-ofpbuf_put(struct ofpbuf *b, const void *p, size_t size)
+ofpbuf_put(struct ofpbuf *b, const void *p, size_t size)
{
void *dst = ofpbuf_put_uninit(b, size);
memcpy(dst, p, size);
/* Reserves 'size' bytes of headroom so that they can be later allocated with
* ofpbuf_push_uninit() without reallocating the ofpbuf. */
void
-ofpbuf_reserve(struct ofpbuf *b, size_t size)
+ofpbuf_reserve(struct ofpbuf *b, size_t size)
{
assert(!b->size);
ofpbuf_prealloc_tailroom(b, size);
}
void *
-ofpbuf_push_uninit(struct ofpbuf *b, size_t size)
+ofpbuf_push_uninit(struct ofpbuf *b, size_t size)
{
ofpbuf_prealloc_headroom(b, size);
b->data = (char*)b->data - size;
return b->data;
}
+/* Prefixes 'size' zeroed bytes to the head end of 'b'. 'b' must have at least
+ * 'size' bytes of headroom. Returns a pointer to the first byte of the data's
+ * location in the ofpbuf. */
void *
-ofpbuf_push(struct ofpbuf *b, const void *p, size_t size)
+ofpbuf_push_zeros(struct ofpbuf *b, size_t size)
+{
+ void *dst = ofpbuf_push_uninit(b, size);
+ memset(dst, 0, size);
+ return dst;
+}
+
+void *
+ofpbuf_push(struct ofpbuf *b, const void *p, size_t size)
{
void *dst = ofpbuf_push_uninit(b, size);
memcpy(dst, p, size);
/* If 'b' contains at least 'offset + size' bytes of data, returns a pointer to
* byte 'offset'. Otherwise, returns a null pointer. */
void *
-ofpbuf_at(const struct ofpbuf *b, size_t offset, size_t size)
+ofpbuf_at(const struct ofpbuf *b, size_t offset, size_t size)
{
return offset + size <= b->size ? (char *) b->data + offset : NULL;
}
/* Returns a pointer to byte 'offset' in 'b', which must contain at least
* 'offset + size' bytes of data. */
void *
-ofpbuf_at_assert(const struct ofpbuf *b, size_t offset, size_t size)
+ofpbuf_at_assert(const struct ofpbuf *b, size_t offset, size_t size)
{
assert(offset + size <= b->size);
return ((char *) b->data) + offset;
/* Returns the byte following the last byte of data in use in 'b'. */
void *
-ofpbuf_tail(const struct ofpbuf *b)
+ofpbuf_tail(const struct ofpbuf *b)
{
return (char *) b->data + b->size;
}
/* Returns the byte following the last byte allocated for use (but not
* necessarily in use) by 'b'. */
void *
-ofpbuf_end(const struct ofpbuf *b)
+ofpbuf_end(const struct ofpbuf *b)
{
return (char *) b->base + b->allocated;
}
/* Clears any data from 'b'. */
void
-ofpbuf_clear(struct ofpbuf *b)
+ofpbuf_clear(struct ofpbuf *b)
{
b->data = b->base;
b->size = 0;
/* Removes 'size' bytes from the head end of 'b', which must contain at least
* 'size' bytes of data. Returns the first byte of data removed. */
void *
-ofpbuf_pull(struct ofpbuf *b, size_t size)
+ofpbuf_pull(struct ofpbuf *b, size_t size)
{
void *data = b->data;
assert(b->size >= size);
* head end of 'b' and returns the first byte removed. Otherwise, returns a
* null pointer without modifying 'b'. */
void *
-ofpbuf_try_pull(struct ofpbuf *b, size_t size)
+ofpbuf_try_pull(struct ofpbuf *b, size_t size)
{
return b->size >= size ? ofpbuf_pull(b, size) : NULL;
}
+
+/* Returns a string that describes some of 'b''s metadata plus a hex dump of up
+ * to 'maxbytes' from the start of the buffer. */
+char *
+ofpbuf_to_string(const struct ofpbuf *b, size_t maxbytes)
+{
+ struct ds s;
+
+ ds_init(&s);
+ ds_put_format(&s, "size=%zu, allocated=%zu, head=%zu, tail=%zu\n",
+ b->size, b->allocated,
+ ofpbuf_headroom(b), ofpbuf_tailroom(b));
+ ds_put_hex_dump(&s, b->data, MIN(b->size, maxbytes), 0, false);
+ return ds_cstr(&s);
+}