static inline int __flush_send_buffer(struct send_buffer *s, struct connection_pair *cp){
register int j, l;
lock_send_buffer(s);
l= (s->end_ptr - s->start_ptr);
if(l <= 0){
unlock_send_buffer(s);
return l;
}
for (j = 0; j < cp->n_remote; ++j) {
if (!cp->remote[j].socketfd)
continue;
if (write (cp->remote[j].socketfd, s->start_ptr, l) < 0) {
close(cp->remote[j].socketfd);
fclose(cp->remote[j].socketfp);
memset(&cp->remote[j], 0, sizeof(struct connection));
continue;
}
}
s->end_ptr = s->start_ptr;
unlock_send_buffer(s);
return l;
}
int get_chunk_from_buffer(struct sb_config *sb, void **ptr, unsigned int chunk_size, struct send_buffer **s){
unsigned int unoccupied;
/* first try */
lock_whole_buffer(sb);
*s= &(sb->buffers[sb->current_buffer]);
unlock_whole_buffer(sb);
lock_send_buffer(*s);
unoccupied= (sb->buffer_size - ((*s)->end_ptr - (*s)->start_ptr));
if (unoccupied >= chunk_size) {
(*ptr)= (*s)->end_ptr;
(*s)->end_ptr += chunk_size;
unlock_send_buffer(*s);
return 0;
}
unlock_send_buffer(*s);
/* move to next buffer and try */
lock_whole_buffer(sb);
++(sb->current_buffer);
sb->current_buffer %= sb->n_buffers;
*s = &(sb->buffers[sb->current_buffer]);
unlock_whole_buffer(sb);
lock_send_buffer(*s);
unoccupied = (sb->buffer_size - ((*s)->end_ptr - (*s)->start_ptr));
if (unoccupied >= chunk_size) {
(*ptr)= (*s)->end_ptr;
(*s)->end_ptr += chunk_size;
unlock_send_buffer(*s);
return 0;
}
unlock_send_buffer(*s);
/* no memory left in buffer to fit chunk_size */
*s=NULL;
return -1;
}
int copy_to_send_buffer(struct sb_config *sb, void *p, unsigned int len)
{
struct send_buffer *tmp = &(sb->buffers[sb->current_buffer]);
unsigned int unoccupied;
lock_send_buffer(tmp);
unoccupied = (sb->buffer_size - (tmp->end_ptr - tmp->start_ptr));
if (unoccupied >= len) {
memcpy(tmp->end_ptr, p, len);
tmp->end_ptr += len;
unlock_send_buffer(tmp);
return 0;
}
unlock_send_buffer(tmp);
pthread_mutex_lock(&sb->lock);
++(sb->current_buffer);
sb->current_buffer %= sb->n_buffers;
pthread_mutex_unlock(&sb->lock);
tmp = &(sb->buffers[sb->current_buffer]);
lock_send_buffer(tmp);
unoccupied = (sb->buffer_size - (tmp->end_ptr - tmp->start_ptr));
if (unoccupied >= len) { /* used to be (unoccupied < len) WHY?? */
memcpy(tmp->end_ptr, p, len);
tmp->end_ptr += len;
unlock_send_buffer(tmp);
return 0;
}
unlock_send_buffer(tmp);
return -1;
}
static inline int flush_send_buffer(struct sb_config *sb, struct send_buffer *s, struct connection_pair *cp){
register int j, l;
int fs, fc;
void *ptr;
lock_send_buffer(s);
/* find first flushable chunk */
bit_ffs(s->bitmap, sb->chunks_in_a_buffer, &fs);
if(fs == -1){ /* nothing flushable */
unlock_send_buffer(s);
return 0;
}
/* find first non-flushable chunk */
bit_ffc(s->bitmap, sb->chunks_in_a_buffer, &fc);
if(fc == -1){ /* everything is flushable */
l= (s->end_ptr - s->start_ptr);
fprintf(stderr, "flushing everything (%d bytes).", l);
for (j = 0; j < cp->n_remote; ++j) {
if (!cp->remote[j].socketfd)
continue;
if (write (cp->remote[j].socketfd, s->start_ptr, l) < 0) {
close(cp->remote[j].socketfd);
fclose(cp->remote[j].socketfp);
memset(&cp->remote[j], 0, sizeof(struct connection));
continue;
}
}
s->end_ptr = s->start_ptr;
bit_nclear(s->bitmap, 0, (sb->chunks_in_a_buffer - 1));
unlock_send_buffer(s);
return l;
}
/* some chunks flushable, some not. flush the first available window and
* only that. this keeps the flush-window moving in only forward direction
*/
ptr= (fs == 0)? (s->start_ptr): ((s->start_ptr) + (fs * sb->chunk_size));
l= ((fc - fs) * sb->chunk_size);
fprintf(stderr, "flushing a range (%d bytes).", l);
for (j = 0; j < cp->n_remote; ++j) {
if (!cp->remote[j].socketfd)
continue;
if (write (cp->remote[j].socketfd, ptr, l) < 0) {
close(cp->remote[j].socketfd);
fclose(cp->remote[j].socketfp);
memset(&cp->remote[j], 0, sizeof(struct connection));
continue;
}
}
/* when and only when the last chunk is flushed, reset the buffer */
if(s->end_ptr == (ptr + l)){
s->end_ptr= s->start_ptr;
bit_nclear(s->bitmap, 0, (sb->chunks_in_a_buffer - 1));
}
unlock_send_buffer(s);
return l;
}
