/*
- * Copyright (c) 2008, 2009, 2010 Nicira Networks.
+ * Copyright (c) 2008, 2009, 2010, 2011, 2012, 2013, 2016 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->header = NULL;
+ b->msg = NULL;
+ list_poison(&b->list_node);
+}
+
+static void
+ofpbuf_use__(struct ofpbuf *b, void *base, size_t allocated, size_t size,
+ enum ofpbuf_source source)
+{
+ b->base = base;
+ b->data = base;
+ b->size = size;
+
+ ofpbuf_init__(b, allocated, source);
+}
+
/* Initializes 'b' as an empty ofpbuf that contains the 'allocated' bytes of
- * memory starting at 'base'.
+ * 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. */
+static void
+ofpbuf_use(struct ofpbuf *b, void *base, size_t allocated)
+{
+ ofpbuf_use__(b, base, allocated, 0, OFPBUF_MALLOC);
+}
+
+/* Converts ds into ofpbuf 'b'. 'b' contains the 'ds->allocated' bytes of
+ * memory starting at 'ds->string'. 'ds' should not be modified any more.
+ * The memory allocated for 'ds' will be freed (with free()) if 'b' is
+ * resized or freed. */
+void
+ofpbuf_use_ds(struct ofpbuf *b, const struct ds *ds)
+{
+ ofpbuf_use__(b, ds->string, ds->allocated + 1, ds->length, 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.
*
- * '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. */
+ * 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(struct ofpbuf *b, void *base, size_t allocated)
+ofpbuf_use_stack(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;
- b->next = NULL;
- b->private_p = NULL;
+ ofpbuf_use__(b, base, allocated, 0, 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, 0, 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.
+ *
+ * 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, CONST_CAST(void *, data), size, size, OFPBUF_STACK);
}
/* 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);
+ if (b->source == OFPBUF_MALLOC) {
+ 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_clone(const struct ofpbuf *buffer)
+ofpbuf_new_with_headroom(size_t size, size_t headroom)
{
- return ofpbuf_clone_data(buffer->data, buffer->size);
+ struct ofpbuf *b = ofpbuf_new(size + headroom);
+ ofpbuf_reserve(b, headroom);
+ return b;
}
+/* Creates and returns a new ofpbuf that initially contains a copy of the
+ * 'buffer->size' bytes of data starting at 'buffer->data' with no headroom or
+ * tailroom. */
struct ofpbuf *
-ofpbuf_clone_data(const void *data, size_t size)
+ofpbuf_clone(const struct ofpbuf *buffer)
{
- struct ofpbuf *b = ofpbuf_new(size);
- ofpbuf_put(b, data, size);
- return b;
+ return ofpbuf_clone_with_headroom(buffer, 0);
}
-/* Frees memory that 'b' points to, as well as 'b' itself. */
-void
-ofpbuf_delete(struct ofpbuf *b)
+/* 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)
{
- if (b) {
- ofpbuf_uninit(b);
- free(b);
+ struct ofpbuf *new_buffer;
+
+ new_buffer = ofpbuf_clone_data_with_headroom(buffer->data,
+ buffer->size,
+ headroom);
+ if (buffer->header) {
+ ptrdiff_t data_delta = (char *)new_buffer->data - (char *)buffer->data;
+
+ new_buffer->header = (char *) buffer->header + data_delta;
}
+ new_buffer->msg = buffer->msg;
+
+ return new_buffer;
}
-/* 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)
+/* 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)
{
- return (char*)b->data - (char*)b->base;
+ return ofpbuf_clone_data_with_headroom(data, size, 0);
}
-/* 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)
+/* 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)
{
- return (char*)ofpbuf_end(b) - (char*)ofpbuf_tail(b);
+ struct ofpbuf *b = ofpbuf_new_with_headroom(size, headroom);
+ ofpbuf_put(b, data, size);
+ return b;
}
-/* 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 (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_copy__(struct ofpbuf *b, uint8_t *new_base,
+ size_t new_headroom, size_t new_tailroom)
+{
+ const uint8_t *old_base = b->base;
+ 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);
+
+ memcpy(&new_base[new_headroom - copy_headroom],
+ &old_base[old_headroom - copy_headroom],
+ copy_headroom + b->size + copy_tailroom);
}
-/* Reallocates 'b' so that it has exactly 'new_tailroom' bytes of tailroom. */
+/* Reallocates 'b' so that it has exactly 'new_headroom' and 'new_tailroom'
+ * bytes of headroom and tailroom, respectively. */
static void
-ofpbuf_resize_tailroom__(struct ofpbuf *b, size_t new_tailroom)
+ofpbuf_resize__(struct ofpbuf *b, size_t new_headroom, size_t new_tailroom)
{
- b->allocated = ofpbuf_headroom(b) + b->size + new_tailroom;
- ofpbuf_rebase__(b, xrealloc(b->base, b->allocated));
+ void *new_base, *new_data;
+ size_t new_allocated;
+
+ new_allocated = new_headroom + b->size + new_tailroom;
+
+ switch (b->source) {
+ case OFPBUF_MALLOC:
+ if (new_headroom == ofpbuf_headroom(b)) {
+ new_base = xrealloc(b->base, new_allocated);
+ } else {
+ new_base = xmalloc(new_allocated);
+ ofpbuf_copy__(b, new_base, new_headroom, new_tailroom);
+ free(b->base);
+ }
+ 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();
+ }
+
+ b->allocated = new_allocated;
+ b->base = new_base;
+
+ new_data = (char *) new_base + new_headroom;
+ if (b->data != new_data) {
+ if (b->header) {
+ ptrdiff_t data_delta = (char *) b->header - (char *) b->data;
+
+ b->header = (char *) new_data + data_delta;
+ }
+ if (b->msg) {
+ ptrdiff_t data_delta = (char *) b->msg - (char *) b->data;
+
+ b->msg = (char *) new_data + data_delta;
+ }
+ b->data = new_data;
+ }
}
/* 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_tailroom(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));
+ 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)
+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. */
+/* Trims the size of 'b' to fit its actual content, reducing its headroom and
+ * tailroom to 0, if any.
+ *
+ * Buffers not obtained from malloc() are not resized, since that wouldn't save
+ * any memory.
+ *
+ * Caller needs to updates 'b->header' and 'b->msg' so that they point to the
+ * same locations in the data. (If they pointed into the tailroom or headroom
+ * then they become invalid.)
+ *
+ */
void
ofpbuf_trim(struct ofpbuf *b)
{
- if (ofpbuf_tailroom(b) > 0) {
- ofpbuf_resize_tailroom__(b, 0);
+ 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 (b->size < length) {
+ ofpbuf_put_zeros(b, length - b->size);
+ }
+}
+
+/* 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').
+ *
+ * If used, user must make sure the 'header' and 'msg' pointers are updated
+ * after shifting.
+ */
+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 *) b->data + delta;
+ memmove(dst, b->data, b->size);
+ b->data = dst;
}
}
* 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);
return dst;
}
+/* Parses as many pairs of hex digits as possible (possibly separated by spaces
+ * or periods) from the beginning of 's', appending bytes for their values to
+ * 'b'. Returns the first character of 's' that is not the first of a pair of
+ * hex digits. If 'n' is nonnull, stores the number of bytes added to 'b' in
+ * '*n'. */
+char *
+ofpbuf_put_hex(struct ofpbuf *b, const char *s, size_t *n)
+{
+ size_t initial_size = b->size;
+ for (;;) {
+ uint8_t byte;
+ bool ok;
+
+ s += strspn(s, " .\t\r\n");
+ byte = hexits_value(s, 2, &ok);
+ if (!ok) {
+ if (n) {
+ *n = b->size - initial_size;
+ }
+ return CONST_CAST(char *, s);
+ }
+
+ ofpbuf_put(b, &byte, 1);
+ s += 2;
+ }
+}
+
/* 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);
+ ovs_assert(!b->size);
ofpbuf_prealloc_tailroom(b, size);
b->data = (char*)b->data + size;
}
+/* 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_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. */
+/* 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)
+ofpbuf_push(struct ofpbuf *b, const void *p, size_t size)
{
void *dst = ofpbuf_push_uninit(b, size);
memcpy(dst, p, size);
return dst;
}
-/* 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)
-{
- 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. */
+/* 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_assert(const struct ofpbuf *b, size_t offset, size_t size)
+ofpbuf_steal_data(struct ofpbuf *b)
{
- 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;
-}
+ void *p;
-/* 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;
+ if (b->source == OFPBUF_MALLOC && b->data == b->base) {
+ p = b->data;
+ } else {
+ p = xmemdup(b->data, b->size);
+ if (b->source == OFPBUF_MALLOC) {
+ free(b->base);
+ }
+ }
+ b->base = NULL;
+ b->data = NULL;
+ b->header = NULL;
+ b->msg = 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",
+ ds_put_format(&s, "size=%"PRIu32", allocated=%"PRIu32", head=%"PRIuSIZE", tail=%"PRIuSIZE"\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);
}
+
+/* Removes each of the "struct ofpbuf"s on 'list' from the list and frees
+ * them. */
+void
+ofpbuf_list_delete(struct ovs_list *list)
+{
+ struct ofpbuf *b;
+
+ LIST_FOR_EACH_POP (b, list_node, list) {
+ ofpbuf_delete(b);
+ }
+}
projects / cascardo / ovs.git / blobdiff