/* Returns the name and offset of the last segment */
int af_last_seg(AFFILE *af,char *last_segname,int last_segname_len,int64 *pos)
{
/* Find the name of the last segment */
fseeko(af->aseg,0,SEEK_END);
af_backspace(af); // back up one segment
*pos = ftello(af->aseg); // remember where it is
last_segname[0] = 0;
return af_probe_next_seg(af,last_segname,last_segname_len,0,0,0,0);
}
static int aff_write_ignore(AFFILE *af,size_t bytes)
{
int64_t startpos = ftello(af->aseg); // remember start position
int r = 0;
if(af_trace) fprintf(af_trace,"aff_write_ignore(%p,%d)\n",af,(int)bytes);
/* First write the ignore */
r = aff_write_ignore2(af,bytes);
/* If the next one is also an ignore,
* then we should go back and make the ignore_size bigger.
* We could do this recursively,
* but it's probably not worth the added complexity.
*/
char next[AF_MAX_NAME_LEN];
size_t segsize2=0;
int count=0;
while(af_probe_next_seg(af,next,sizeof(next),0,0,&segsize2,1)==0 && next[0]==0 && segsize2>=0){
count++;
if(count>10) break; // something is wrong; just get out.
//printf("*** next %d segment at %qd len=%d will be deleted\n",count,ftello(af->aseg),segsize2);
bytes += segsize2;
fseeko(af->aseg,startpos,SEEK_SET);
r = aff_write_ignore2(af,bytes);
if(r!=0) return r;
}
/* See if the previous segment is also blank; if so, collapse them */
fseeko(af->aseg,startpos,SEEK_SET);
if(af_backspace(af)==0){
uint64_t prev_segment_loc = ftello(af->aseg); // remember where we are
char prev_segment_name[AF_MAX_NAME_LEN];
size_t prev_segment_size=0;
if(af_probe_next_seg(af,prev_segment_name,sizeof(prev_segment_name),0,0,&prev_segment_size,1)==0){
//printf("** prev segment name='%s' len=%d\n",prev_segment_name,prev_segment_size);
if(prev_segment_name[0]==0){
bytes += prev_segment_size;
fseeko(af->aseg,prev_segment_loc,SEEK_SET);
r = aff_write_ignore2(af,bytes);
fseeko(af->aseg,prev_segment_loc,SEEK_SET);
}
}
}
return(r);
}
/* Removes the last segment of an AFF file if it is blank.
* @return 0 for success, -1 for error */
int af_truncate_blank(AFFILE *af)
{
uint64_t last_loc = ftello(af->aseg); // remember where we are
if(af_backspace(af)==0){
uint64_t backspace_loc = ftello(af->aseg); // remember where we are
char next_segment_name[AF_MAX_NAME_LEN];
if(af_probe_next_seg(af,next_segment_name,sizeof(next_segment_name),0,0,0,1)==0){
if(next_segment_name[0]==0){
/* Remove it */
fflush(af->aseg);
if(ftruncate(fileno(af->aseg),backspace_loc)<0) return -1;
return 0;
}
}
}
fseeko(af->aseg,last_loc,SEEK_SET); // return to where we were
return -1; // say that we couldn't do it.
}