Exemple #1
0
/* Trims the size of 'b' to fit its actual content, reducing its tailroom to
 * 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 (b->source == OFPBUF_MALLOC
        && (ofpbuf_headroom(b) || ofpbuf_tailroom(b))) {
        ofpbuf_resize__(b, 0, 0);
    }
}
Exemple #2
0
/* Reallocates 'b' so that it has exactly 'new_headroom' and 'new_tailroom'
 * bytes of headroom and tailroom, respectively. */
static void
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 + 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:
        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:
        NOT_REACHED();
    }

    b->allocated = new_allocated;
    b->base = new_base;

    new_data = (char *) new_base + new_headroom;
    if (b->data != new_data) {
        uintptr_t data_delta = (char *) new_data - (char *) b->data;
        b->data = new_data;
        if (b->l2) {
            b->l2 = (char *) b->l2 + data_delta;
        }
        if (b->l2_5) {
            b->l2_5 = (char *) b->l2_5 + data_delta;
        }
        if (b->l3) {
            b->l3 = (char *) b->l3 + data_delta;
        }
        if (b->l4) {
            b->l4 = (char *) b->l4 + data_delta;
        }
        if (b->l7) {
            b->l7 = (char *) b->l7 + data_delta;
        }
    }
}
Exemple #3
0
/* 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=%"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);
}
Exemple #4
0
/* 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;
    }
}
Exemple #5
0
/* 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);
    }
}
Exemple #6
0
/* Reallocates 'b' so that it has exactly 'new_headroom' and 'new_tailroom'
 * bytes of headroom and tailroom, respectively. */
static void
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 + 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) {
            uintptr_t data_delta = (char *) b->header - (char *) b->data;

            b->header = (char *) new_data + data_delta;
        }
        if (b->msg) {
            uintptr_t data_delta = (char *) b->msg - (char *) b->data;

            b->msg = (char *) new_data + data_delta;
        }
        b->data = new_data;
    }
}
Exemple #7
0
static void
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);
}
Exemple #8
0
/* Reallocates 'b' so that it has exactly 'new_headroom' and 'new_tailroom'
 * bytes of headroom and tailroom, respectively. */
static void
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();
    }

    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);
    }
}
Exemple #9
0
void
ofpbuf_prealloc_headroom(struct ofpbuf *b, size_t size) 
{
    assert(size <= ofpbuf_headroom(b));
}
Exemple #10
0
/* 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));
}