/*
- * Copyright (c) 2008, 2009, 2010 Nicira Networks.
+ * Copyright (c) 2008, 2009, 2010, 2011, 2012, 2013 Nicira, Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
#include <config.h>
#include "ofpbuf.h"
-#include <assert.h>
#include <stdlib.h>
#include <string.h>
#include "dynamic-string.h"
+#include "netdev-dpdk.h"
#include "util.h"
+static void
+ofpbuf_init__(struct ofpbuf *b, size_t allocated, enum ofpbuf_source source)
+{
+ b->allocated = allocated;
+ b->source = source;
+ b->frame = NULL;
+ b->l2_5_ofs = b->l3_ofs = b->l4_ofs = UINT16_MAX;
+ list_poison(&b->list_node);
+}
+
+static void
+ofpbuf_use__(struct ofpbuf *b, void *base, size_t allocated,
+ enum ofpbuf_source source)
+{
+ ofpbuf_set_base(b, base);
+ ofpbuf_set_data(b, base);
+ ofpbuf_set_size(b, 0);
+
+ ofpbuf_init__(b, allocated, source);
+}
+
/* Initializes 'b' as an empty ofpbuf that contains the 'allocated' bytes of
- * memory starting at 'base'.
- *
- * 'base' should ordinarily be the first byte of a region obtained from
- * malloc(), but in circumstances where it can be guaranteed that 'b' will
- * never need to be expanded or freed, it can be a pointer into arbitrary
- * memory. */
+ * memory starting at 'base'. 'base' should be the first byte of a region
+ * obtained from malloc(). It will be freed (with free()) if 'b' is resized or
+ * freed. */
void
ofpbuf_use(struct ofpbuf *b, void *base, size_t allocated)
{
- b->base = b->data = base;
- b->allocated = allocated;
- b->size = 0;
- b->l2 = b->l3 = b->l4 = b->l7 = NULL;
- list_poison(&b->list_node);
- b->private_p = NULL;
+ ofpbuf_use__(b, base, allocated, OFPBUF_MALLOC);
+}
+
+/* Initializes 'b' as an empty ofpbuf that contains the 'allocated' bytes of
+ * memory starting at 'base'. 'base' should point to a buffer on the stack.
+ * (Nothing actually relies on 'base' being allocated on the stack. It could
+ * be static or malloc()'d memory. But stack space is the most common use
+ * case.)
+ *
+ * 'base' should be appropriately aligned. Using an array of uint32_t or
+ * uint64_t for the buffer is a reasonable way to ensure appropriate alignment
+ * for 32- or 64-bit data.
+ *
+ * An ofpbuf operation that requires reallocating data will assert-fail if this
+ * function was used to initialize it. Thus, one need not call ofpbuf_uninit()
+ * on an ofpbuf initialized by this function (though doing so is harmless),
+ * because it is guaranteed that 'b' does not own any heap-allocated memory. */
+void
+ofpbuf_use_stack(struct ofpbuf *b, void *base, size_t allocated)
+{
+ ofpbuf_use__(b, base, allocated, OFPBUF_STACK);
+}
+
+/* Initializes 'b' as an empty ofpbuf that contains the 'allocated' bytes of
+ * memory starting at 'base'. 'base' should point to a buffer on the stack.
+ * (Nothing actually relies on 'base' being allocated on the stack. It could
+ * be static or malloc()'d memory. But stack space is the most common use
+ * case.)
+ *
+ * 'base' should be appropriately aligned. Using an array of uint32_t or
+ * uint64_t for the buffer is a reasonable way to ensure appropriate alignment
+ * for 32- or 64-bit data.
+ *
+ * An ofpbuf operation that requires reallocating data will copy the provided
+ * buffer into a malloc()'d buffer. Thus, it is wise to call ofpbuf_uninit()
+ * on an ofpbuf initialized by this function, so that if it expanded into the
+ * heap, that memory is freed. */
+void
+ofpbuf_use_stub(struct ofpbuf *b, void *base, size_t allocated)
+{
+ ofpbuf_use__(b, base, allocated, OFPBUF_STUB);
}
/* Initializes 'b' as an ofpbuf whose data starts at 'data' and continues for
* 'size' bytes. This is appropriate for an ofpbuf that will be used to
* inspect existing data, without moving it around or reallocating it, and
- * generally without modifying it at all. */
+ * generally without modifying it at all.
+ *
+ * An ofpbuf operation that requires reallocating data will assert-fail if this
+ * function was used to initialize it. */
void
ofpbuf_use_const(struct ofpbuf *b, const void *data, size_t size)
{
- ofpbuf_use(b, (void *) data, size);
- b->size = size;
+ ofpbuf_use__(b, CONST_CAST(void *, data), size, OFPBUF_STACK);
+ ofpbuf_set_size(b, size);
+}
+
+/* Initializes 'b' as an empty ofpbuf that contains the 'allocated' bytes of
+ * memory starting at 'base'. DPDK allocated ofpbuf and *data is allocated
+ * from one continous memory region, so in memory data start right after
+ * ofpbuf. Therefore there is special method to free this type of
+ * buffer. ofpbuf base, data and size are initialized by dpdk rcv() so no
+ * need to initialize those fields. */
+void
+ofpbuf_init_dpdk(struct ofpbuf *b, size_t allocated)
+{
+ ofpbuf_init__(b, allocated, OFPBUF_DPDK);
}
/* Initializes 'b' as an empty ofpbuf with an initial capacity of 'size'
ofpbuf_uninit(struct ofpbuf *b)
{
if (b) {
- free(b->base);
+ if (b->source == OFPBUF_MALLOC) {
+ free(ofpbuf_base(b));
+ }
+ ovs_assert(b->source != OFPBUF_DPDK);
}
}
return b;
}
+/* Creates and returns a new ofpbuf that initially contains a copy of the
+ * 'ofpbuf_size(buffer)' bytes of data starting at 'buffer->data' with no headroom or
+ * tailroom. */
struct ofpbuf *
ofpbuf_clone(const struct ofpbuf *buffer)
{
- return ofpbuf_clone_data(buffer->data, buffer->size);
+ return ofpbuf_clone_with_headroom(buffer, 0);
}
/* Creates and returns a new ofpbuf whose data are copied from 'buffer'. The
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 *new_buffer;
+
+ new_buffer = ofpbuf_clone_data_with_headroom(ofpbuf_data(buffer),
+ ofpbuf_size(buffer),
+ headroom);
+ if (buffer->frame) {
+ uintptr_t data_delta
+ = (char *)ofpbuf_data(new_buffer) - (char *)ofpbuf_data(buffer);
+
+ new_buffer->frame = (char *) buffer->frame + data_delta;
+ }
+ new_buffer->l2_5_ofs = buffer->l2_5_ofs;
+ new_buffer->l3_ofs = buffer->l3_ofs;
+ new_buffer->l4_ofs = buffer->l4_ofs;
+
+ return new_buffer;
}
+/* Creates and returns a new ofpbuf that initially contains a copy of the
+ * 'size' bytes of data starting at 'data' with no headroom or tailroom. */
struct ofpbuf *
ofpbuf_clone_data(const void *data, size_t size)
{
- struct ofpbuf *b = ofpbuf_new(size);
- ofpbuf_put(b, data, size);
- return b;
+ return ofpbuf_clone_data_with_headroom(data, size, 0);
}
-/* Frees memory that 'b' points to, as well as 'b' itself. */
-void
-ofpbuf_delete(struct ofpbuf *b)
+/* Creates and returns a new ofpbuf that initially contains 'headroom' bytes of
+ * headroom followed by a copy of the 'size' bytes of data starting at
+ * 'data'. */
+struct ofpbuf *
+ofpbuf_clone_data_with_headroom(const void *data, size_t size, size_t headroom)
{
- if (b) {
- ofpbuf_uninit(b);
- free(b);
- }
+ struct ofpbuf *b = ofpbuf_new_with_headroom(size, headroom);
+ ofpbuf_put(b, data, size);
+ return b;
}
-/* Returns the number of bytes of headroom in 'b', that is, the number of bytes
- * of unused space in ofpbuf 'b' before the data that is in use. (Most
- * commonly, the data in a ofpbuf is at its beginning, and thus the ofpbuf's
- * headroom is 0.) */
-size_t
-ofpbuf_headroom(const struct ofpbuf *b)
+static void
+ofpbuf_copy__(struct ofpbuf *b, uint8_t *new_base,
+ size_t new_headroom, size_t new_tailroom)
{
- return (char*)b->data - (char*)b->base;
-}
+ const uint8_t *old_base = ofpbuf_base(b);
+ size_t old_headroom = ofpbuf_headroom(b);
+ size_t old_tailroom = ofpbuf_tailroom(b);
+ size_t copy_headroom = MIN(old_headroom, new_headroom);
+ size_t copy_tailroom = MIN(old_tailroom, new_tailroom);
-/* 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(const struct ofpbuf *b)
-{
- return (char*)ofpbuf_end(b) - (char*)ofpbuf_tail(b);
+ memcpy(&new_base[new_headroom - copy_headroom],
+ &old_base[old_headroom - copy_headroom],
+ copy_headroom + ofpbuf_size(b) + copy_tailroom);
}
-/* Changes 'b->base' to 'new_base' and adjusts all of 'b''s internal pointers
- * to reflect the change. */
+/* Reallocates 'b' so that it has exactly 'new_headroom' and 'new_tailroom'
+ * bytes of headroom and tailroom, respectively. */
static void
-ofpbuf_rebase__(struct ofpbuf *b, void *new_base)
-{
- if (b->base != new_base) {
- uintptr_t base_delta = (char*)new_base - (char*)b->base;
- b->base = new_base;
- b->data = (char*)b->data + base_delta;
- if (b->l2) {
- b->l2 = (char*)b->l2 + base_delta;
- }
- if (b->l3) {
- b->l3 = (char*)b->l3 + base_delta;
- }
- if (b->l4) {
- b->l4 = (char*)b->l4 + base_delta;
- }
- if (b->l7) {
- b->l7 = (char*)b->l7 + base_delta;
+ofpbuf_resize__(struct ofpbuf *b, size_t new_headroom, size_t new_tailroom)
+{
+ void *new_base, *new_data;
+ size_t new_allocated;
+
+ new_allocated = new_headroom + ofpbuf_size(b) + new_tailroom;
+
+ switch (b->source) {
+ case OFPBUF_DPDK:
+ OVS_NOT_REACHED();
+
+ case OFPBUF_MALLOC:
+ if (new_headroom == ofpbuf_headroom(b)) {
+ new_base = xrealloc(ofpbuf_base(b), new_allocated);
+ } else {
+ new_base = xmalloc(new_allocated);
+ ofpbuf_copy__(b, new_base, new_headroom, new_tailroom);
+ free(ofpbuf_base(b));
}
+ break;
+
+ case OFPBUF_STACK:
+ OVS_NOT_REACHED();
+
+ case OFPBUF_STUB:
+ b->source = OFPBUF_MALLOC;
+ new_base = xmalloc(new_allocated);
+ ofpbuf_copy__(b, new_base, new_headroom, new_tailroom);
+ break;
+
+ default:
+ OVS_NOT_REACHED();
}
-}
-/* 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));
+ b->allocated = new_allocated;
+ ofpbuf_set_base(b, new_base);
+
+ new_data = (char *) new_base + new_headroom;
+ if (ofpbuf_data(b) != new_data) {
+ if (b->frame) {
+ uintptr_t data_delta = (char *) new_data - (char *) ofpbuf_data(b);
+
+ b->frame = (char *) b->frame + data_delta;
+ }
+ ofpbuf_set_data(b, new_data);
+ }
}
/* Ensures that 'b' has room for at least 'size' bytes at its tail end,
ofpbuf_prealloc_tailroom(struct ofpbuf *b, size_t size)
{
if (size > ofpbuf_tailroom(b)) {
- ofpbuf_resize_tailroom__(b, MAX(size, 64));
+ ofpbuf_resize__(b, ofpbuf_headroom(b), MAX(size, 64));
}
}
+/* Ensures that 'b' has room for at least 'size' bytes at its head,
+ * reallocating and copying its data if necessary. Its tailroom, if any, is
+ * preserved. */
void
ofpbuf_prealloc_headroom(struct ofpbuf *b, size_t size)
{
- assert(size <= ofpbuf_headroom(b));
+ if (size > ofpbuf_headroom(b)) {
+ ofpbuf_resize__(b, MAX(size, 64), ofpbuf_tailroom(b));
+ }
}
/* Trims the size of 'b' to fit its actual content, reducing its tailroom to
- * 0. Its headroom, if any, is preserved. */
+ * 0. Its headroom, if any, is preserved.
+ *
+ * Buffers not obtained from malloc() are not resized, since that wouldn't save
+ * any memory. */
void
ofpbuf_trim(struct ofpbuf *b)
{
- if (ofpbuf_tailroom(b) > 0) {
- ofpbuf_resize_tailroom__(b, 0);
+ ovs_assert(b->source != OFPBUF_DPDK);
+
+ if (b->source == OFPBUF_MALLOC
+ && (ofpbuf_headroom(b) || ofpbuf_tailroom(b))) {
+ ofpbuf_resize__(b, 0, 0);
+ }
+}
+
+/* If 'b' is shorter than 'length' bytes, pads its tail out with zeros to that
+ * length. */
+void
+ofpbuf_padto(struct ofpbuf *b, size_t length)
+{
+ if (ofpbuf_size(b) < length) {
+ ofpbuf_put_zeros(b, length - ofpbuf_size(b));
+ }
+}
+
+/* Shifts all of the data within the allocated space in 'b' by 'delta' bytes.
+ * For example, a 'delta' of 1 would cause each byte of data to move one byte
+ * forward (from address 'p' to 'p+1'), and a 'delta' of -1 would cause each
+ * byte to move one byte backward (from 'p' to 'p-1'). */
+void
+ofpbuf_shift(struct ofpbuf *b, int delta)
+{
+ ovs_assert(delta > 0 ? delta <= ofpbuf_tailroom(b)
+ : delta < 0 ? -delta <= ofpbuf_headroom(b)
+ : true);
+
+ if (delta != 0) {
+ char *dst = (char *) ofpbuf_data(b) + delta;
+ memmove(dst, ofpbuf_data(b), ofpbuf_size(b));
+ ofpbuf_set_data(b, dst);
}
}
void *p;
ofpbuf_prealloc_tailroom(b, size);
p = ofpbuf_tail(b);
- b->size += size;
+ ofpbuf_set_size(b, ofpbuf_size(b) + size);
return p;
}
char *
ofpbuf_put_hex(struct ofpbuf *b, const char *s, size_t *n)
{
- size_t initial_size = b->size;
+ size_t initial_size = ofpbuf_size(b);
for (;;) {
uint8_t byte;
bool ok;
- s += strspn(s, " ");
+ s += strspn(s, " \t\r\n");
byte = hexits_value(s, 2, &ok);
if (!ok) {
if (n) {
- *n = b->size - initial_size;
+ *n = ofpbuf_size(b) - initial_size;
}
- return (char *) s;
+ return CONST_CAST(char *, s);
}
ofpbuf_put(b, &byte, 1);
void
ofpbuf_reserve(struct ofpbuf *b, size_t size)
{
- assert(!b->size);
+ ovs_assert(!ofpbuf_size(b));
ofpbuf_prealloc_tailroom(b, size);
- b->data = (char*)b->data + size;
+ ofpbuf_set_data(b, (char*)ofpbuf_data(b) + size);
+}
+
+/* Reserves 'size' bytes of headroom so that they can be later allocated with
+ * ofpbuf_push_uninit() without reallocating the ofpbuf. */
+void
+ofpbuf_reserve_with_tailroom(struct ofpbuf *b, size_t headroom,
+ size_t tailroom)
+{
+ ovs_assert(!ofpbuf_size(b));
+ ofpbuf_prealloc_tailroom(b, headroom + tailroom);
+ ofpbuf_set_data(b, (char*)ofpbuf_data(b) + headroom);
}
+/* Prefixes 'size' bytes to the head end of 'b', reallocating and copying its
+ * data if necessary. Returns a pointer to the first byte of the data's
+ * location in the ofpbuf. The new data is left uninitialized. */
void *
ofpbuf_push_uninit(struct ofpbuf *b, size_t size)
{
ofpbuf_prealloc_headroom(b, size);
- b->data = (char*)b->data - size;
- b->size += size;
- return b->data;
+ ofpbuf_set_data(b, (char*)ofpbuf_data(b) - size);
+ ofpbuf_set_size(b, ofpbuf_size(b) + size);
+ return ofpbuf_data(b);
}
-/* 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. */
+/* Prefixes 'size' zeroed bytes to the head end of 'b', reallocating and
+ * copying its data if necessary. Returns a pointer to the first byte of the
+ * data's location in the ofpbuf. */
void *
ofpbuf_push_zeros(struct ofpbuf *b, size_t size)
{
return dst;
}
+/* Copies the 'size' bytes starting at 'p' to the head end of 'b', reallocating
+ * and copying its data if necessary. 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)
{
return dst;
}
-/* If 'b' contains at least 'offset + size' bytes of data, returns a pointer to
- * byte 'offset'. Otherwise, returns a null pointer. */
+/* Returns the data in 'b' as a block of malloc()'d memory and frees the buffer
+ * within 'b'. (If 'b' itself was dynamically allocated, e.g. with
+ * ofpbuf_new(), then it should still be freed with, e.g., ofpbuf_delete().) */
void *
-ofpbuf_at(const struct ofpbuf *b, size_t offset, size_t size)
+ofpbuf_steal_data(struct ofpbuf *b)
{
- 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)
-{
- 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)
-{
- 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)
-{
- return (char *) b->base + b->allocated;
-}
-
-/* Clears any data from 'b'. */
-void
-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)
-{
- void *data = b->data;
- assert(b->size >= size);
- b->data = (char*)b->data + size;
- b->size -= size;
- return data;
-}
-
-/* If 'b' has at least 'size' bytes of data, removes that many bytes from the
- * 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)
-{
- return b->size >= size ? ofpbuf_pull(b, size) : NULL;
+ void *p;
+ ovs_assert(b->source != OFPBUF_DPDK);
+
+ if (b->source == OFPBUF_MALLOC && ofpbuf_data(b) == ofpbuf_base(b)) {
+ p = ofpbuf_data(b);
+ } else {
+ p = xmemdup(ofpbuf_data(b), ofpbuf_size(b));
+ if (b->source == OFPBUF_MALLOC) {
+ free(ofpbuf_base(b));
+ }
+ }
+ ofpbuf_set_base(b, NULL);
+ ofpbuf_set_data(b, NULL);
+ return p;
}
/* Returns a string that describes some of 'b''s metadata plus a hex dump of up
struct ds s;
ds_init(&s);
- ds_put_format(&s, "size=%zu, allocated=%zu, head=%zu, tail=%zu\n",
- b->size, b->allocated,
+ ds_put_format(&s, "size=%"PRIu32", allocated=%"PRIu32", head=%"PRIuSIZE", tail=%"PRIuSIZE"\n",
+ ofpbuf_size(b), b->allocated,
ofpbuf_headroom(b), ofpbuf_tailroom(b));
- ds_put_hex_dump(&s, b->data, MIN(b->size, maxbytes), 0, false);
+ ds_put_hex_dump(&s, ofpbuf_data(b), MIN(ofpbuf_size(b), maxbytes), 0, false);
return ds_cstr(&s);
}
ofpbuf_delete(b);
}
}
+
+static inline void
+ofpbuf_adjust_layer_offset(uint16_t *offset, int increment)
+{
+ if (*offset != UINT16_MAX) {
+ *offset += increment;
+ }
+}
+
+/* Adjust the size of the l2_5 portion of the ofpbuf, updating the l2
+ * pointer and the layer offsets. The caller is responsible for
+ * modifying the contents. */
+void *
+ofpbuf_resize_l2_5(struct ofpbuf *b, int increment)
+{
+ if (increment >= 0) {
+ ofpbuf_push_uninit(b, increment);
+ } else {
+ ofpbuf_pull(b, -increment);
+ }
+
+ b->frame = ofpbuf_data(b);
+ /* Adjust layer offsets after l2_5. */
+ ofpbuf_adjust_layer_offset(&b->l3_ofs, increment);
+ ofpbuf_adjust_layer_offset(&b->l4_ofs, increment);
+
+ return b->frame;
+}
+
+/* Adjust the size of the l2 portion of the ofpbuf, updating the l2
+ * pointer and the layer offsets. The caller is responsible for
+ * modifying the contents. */
+void *
+ofpbuf_resize_l2(struct ofpbuf *b, int increment)
+{
+ ofpbuf_resize_l2_5(b, increment);
+ ofpbuf_adjust_layer_offset(&b->l2_5_ofs, increment);
+ return b->frame;
+}