void ncbmb_init(struct ncbmbuf *buf, ncb_sz_t head);
struct ncbmbuf ncbmb_make(char *area, ncb_sz_t size, ncb_sz_t head);
+/* Returns start of allocated buffer area. */
+static inline char *ncbmb_orig(const struct ncbmbuf *buf)
+{
+ return buf->area;
+}
+
+/* Returns current head pointer into buffer area. */
+static inline char *ncbmb_head(const struct ncbmbuf *buf)
+{
+ return buf->area + buf->head;
+}
+
+/* Returns the first byte after the allocated buffer area. */
+static inline char *ncbmb_wrap(const struct ncbmbuf *buf)
+{
+ return buf->area + buf->size;
+}
+
/* Returns the usable size of <buf> for data storage. This is the size of the
* allocated buffer without the bitmap space.
*/
int ncbmb_is_empty(const struct ncbmbuf *buf);
+enum ncb_ret ncbmb_add(struct ncbmbuf *buf, ncb_sz_t off,
+ const char *data, ncb_sz_t len, enum ncb_add_mode mode);
+
#endif /* _HAPROXY_NCBMBUF_H */
# define BUG_ON_HOT(x) if (x) { fprintf(stderr, "CRASH ON %s:%d\n", __func__, __LINE__); abort(); }
#endif /* DEBUG_STRICT */
+/* ******** internal API ******** */
+
+static char *ncbmb_peek(const struct ncbmbuf *buf, ncb_sz_t off)
+{
+ char *ptr = ncbmb_head(buf) + off;
+ if (ptr >= buf->area + buf->size)
+ ptr -= buf->size;
+ return ptr;
+}
+
+static void ncbmb_set_bitmap(struct ncbmbuf *buf, ncb_sz_t off, ncb_sz_t len)
+{
+ const ncb_sz_t sz = ncbmb_size(buf);
+ ncb_sz_t off_abs;
+ unsigned char mod;
+ unsigned char *b;
+
+ off_abs = off < sz ? off : off - sz;
+ b = buf->bitmap + (off_abs / 8);
+
+ mod = off_abs % 8;
+ if (mod) {
+ /* adjust first bitmap byte bit by bit if not aligned on 8 */
+ unsigned char to_copy = len < 8 - mod ? len : 8 - mod;
+ *b |= (unsigned char)(0xff << (8 - to_copy)) >> mod;
+ len -= to_copy;
+ ++b;
+ }
+
+ if (len) {
+ size_t to_copy = len / 8;
+ /* bulk set bitmap as many as possible */
+ if (to_copy) {
+ memset(b, 0xff, to_copy);
+ len -= 8 * to_copy;
+ b += to_copy;
+ }
+
+ if (len) {
+ /* adjust last bitmap byte shifted by remaining len */
+ *b |= 0xff << (8 - len);
+ }
+ }
+}
+
+/* ******** public API ******** */
+
/* Initialize or reset <buf> by clearing all data. Its size is untouched.
* Buffer is positioned to <head> offset. Use 0 to realign it. <buf> must not
* be NCBUF_NULL.
return 0;
}
+/* Add a new block at <data> of size <len> in <buf> at offset <off>. Note that
+ * currently only NCB_ADD_OVERWRT mode is supported.
+ *
+ * Always returns NCB_RET_OK as this operation cannot fail.
+ */
enum ncb_ret ncbmb_add(struct ncbmbuf *buf, ncb_sz_t off,
const char *data, ncb_sz_t len, enum ncb_add_mode mode)
{
- /* TODO */
+ char *ptr = ncbmb_peek(buf, off);
+
+ BUG_ON_HOT(mode != NCB_ADD_OVERWRT);
+
+ BUG_ON_HOT(off + len > buf->size);
+
+ if (ptr + len >= ncbmb_wrap(buf)) {
+ ncb_sz_t sz1 = ncbmb_wrap(buf) - ptr;
+
+ memcpy(ptr, data, sz1);
+ ncbmb_set_bitmap(buf, buf->head + off, sz1);
+
+ memcpy(ncbmb_orig(buf), data + sz1, len - sz1);
+ ncbmb_set_bitmap(buf, 0, len - sz1);
+ }
+ else {
+ memcpy(ptr, data, len);
+ ncbmb_set_bitmap(buf, buf->head + off, len);
+ }
+
return NCB_RET_OK;
}
projects / thirdparty / haproxy.git / commitdiff
