+
+int bcf_append_info(bcf1_t *b, const char *info, int l)
+{
+ int shift = b->fmt - b->str;
+ int l_fmt = b->l_str - shift;
+ char *ori = b->str;
+ if (b->l_str + l > b->m_str) { // enlarge if necessary
+ b->m_str = b->l_str + l;
+ kroundup32(b->m_str);
+ b->str = realloc(b->str, b->m_str);
+ }
+ memmove(b->str + shift + l, b->str + shift, l_fmt); // move the FORMAT field
+ memcpy(b->str + shift - 1, info, l); // append to the INFO field
+ b->str[shift + l - 1] = '\0';
+ b->fmt = b->str + shift + l;
+ b->l_str += l;
+ if (ori != b->str) bcf_sync(b); // synchronize when realloc changes the pointer
+ return 0;
+}
+
+int remove_tag(char *str, const char *tag, char delim)
+{
+ char *tmp = str, *p;
+ int len_diff = 0, ori_len = strlen(str);
+ while ( *tmp && (p = strstr(tmp,tag)) )
+ {
+ if ( p>str )
+ {
+ if ( *(p-1)!=delim ) { tmp=p+1; continue; } // shared substring
+ p--;
+ }
+ char *q=p+1;
+ while ( *q && *q!=delim ) q++;
+ if ( p==str && *q ) q++; // the tag is first, don't move the delim char
+ len_diff += q-p;
+ if ( ! *q ) { *p = 0; break; } // the tag was last, no delim follows
+ else
+ memmove(p,q,ori_len-(int)(p-str)-(int)(q-p)); // *q==delim
+ }
+ if ( len_diff==ori_len )
+ str[0]='.', str[1]=0, len_diff--;
+
+ return len_diff;
+}
+
+
+void rm_info(kstring_t *s, const char *key)
+{
+ char *p = s->s;
+ int n = 0;
+ while ( n<4 )
+ {
+ if ( !*p ) n++;
+ p++;
+ }
+ char *q = p+1;
+ while ( *q && q-s->s<s->l ) q++;
+
+ int nrm = remove_tag(p, key, ';');
+ if ( nrm )
+ memmove(q-nrm, q, s->s+s->l-q+1);
+ s->l -= nrm;
+}
+
+int bcf_cpy(bcf1_t *r, const bcf1_t *b)
+{
+ char *t1 = r->str;
+ bcf_ginfo_t *t2 = r->gi;
+ int i, t3 = r->m_str, t4 = r->m_gi;
+ *r = *b;
+ r->str = t1; r->gi = t2; r->m_str = t3; r->m_gi = t4;
+ if (r->m_str < b->m_str) {
+ r->m_str = b->m_str;
+ r->str = realloc(r->str, r->m_str);
+ }
+ memcpy(r->str, b->str, r->m_str);
+ bcf_sync(r); // calling bcf_sync() is simple but inefficient
+ for (i = 0; i < r->n_gi; ++i)
+ memcpy(r->gi[i].data, b->gi[i].data, r->n_smpl * r->gi[i].len);
+ return 0;
+}
+
+int bcf_is_indel(const bcf1_t *b)
+{
+ char *p;
+ if (strlen(b->ref) > 1) return 1;
+ for (p = b->alt; *p; ++p)
+ if (*p != ',' && p[1] != ',' && p[1] != '\0')
+ return 1;
+ return 0;
+}