off_t hseek(hFILE *fp, off_t offset, int whence)
{
off_t curpos, pos;
if (writebuffer_is_nonempty(fp) && fp->mobile) {
int ret = flush_buffer(fp);
if (ret < 0) return ret;
}
curpos = htell(fp);
// Relative offsets are given relative to the hFILE's stream position,
// which may differ from the backend's physical position due to buffering
// read-ahead. Correct for this by converting to an absolute position.
if (whence == SEEK_CUR) {
if (curpos + offset < 0) {
// Either a negative offset resulted in a position before the
// start of the file, or we overflowed when given a positive offset
fp->has_errno = errno = (offset < 0)? EINVAL : EOVERFLOW;
return -1;
}
whence = SEEK_SET;
offset = curpos + offset;
}
// For fixed immobile buffers, convert everything else to SEEK_SET too
// so that seeking can be avoided for all (within range) requests.
else if (! fp->mobile && whence == SEEK_END) {
size_t length = fp->end - fp->buffer;
if (offset > 0 || -offset > length) {
fp->has_errno = errno = EINVAL;
return -1;
}
whence = SEEK_SET;
offset = length + offset;
}
// Avoid seeking if the desired position is within our read buffer.
// (But not when the next operation may be a write on a mobile buffer.)
if (whence == SEEK_SET && (! fp->mobile || fp->readonly) &&
offset >= fp->offset && offset - fp->offset <= fp->end - fp->buffer) {
fp->begin = &fp->buffer[offset - fp->offset];
return offset;
}
pos = fp->backend->seek(fp, offset, whence);
if (pos < 0) { fp->has_errno = errno; return pos; }
// Seeking succeeded, so discard any non-empty read buffer
fp->begin = fp->end = fp->buffer;
fp->at_eof = 0;
fp->offset = pos;
return pos;
}
void check_offset(hFILE *f, off_t off, const char *message)
{
off_t ret = htell(f);
if (ret < 0) fail("htell(%s)", message);
if (ret == off) return;
fprintf(stderr, "%s offset incorrect: expected %ld but got %ld\n",
message, (long)off, (long)ret);
exit(EXIT_FAILURE);
}
/*
* Builds an index file.
*
* fd is a newly opened cram file that we wish to index.
* fn_base is the filename of the associated CRAM file. Internally we
* add ".crai" to this to get the index filename.
*
* Returns 0 on success
* -1 on failure
*/
int cram_index_build(cram_fd *fd, const char *fn_base) {
cram_container *c;
off_t cpos, spos, hpos;
zfp *fp;
char fn_idx[PATH_MAX];
if (strlen(fn_base) > PATH_MAX-6)
return -1;
sprintf(fn_idx, "%s.crai", fn_base);
if (!(fp = zfopen(fn_idx, "wz"))) {
perror(fn_idx);
return -1;
}
cpos = htell(fd->fp);
while ((c = cram_read_container(fd))) {
int j;
if (fd->err) {
perror("Cram container read");
return 1;
}
hpos = htell(fd->fp);
if (!(c->comp_hdr_block = cram_read_block(fd)))
return 1;
assert(c->comp_hdr_block->content_type == COMPRESSION_HEADER);
c->comp_hdr = cram_decode_compression_header(fd, c->comp_hdr_block);
if (!c->comp_hdr)
return -1;
// 2.0 format
for (j = 0; j < c->num_landmarks; j++) {
char buf[1024];
cram_slice *s;
int sz;
spos = htell(fd->fp);
assert(spos - cpos - c->offset == c->landmark[j]);
if (!(s = cram_read_slice(fd))) {
zfclose(fp);
return -1;
}
sz = (int)(htell(fd->fp) - spos);
if (s->hdr->ref_seq_id == -2) {
cram_index_build_multiref(fd, c, s, fp,
cpos, c->landmark[j], sz);
} else {
sprintf(buf, "%d\t%d\t%d\t%"PRId64"\t%d\t%d\n",
s->hdr->ref_seq_id, s->hdr->ref_seq_start,
s->hdr->ref_seq_span, (int64_t)cpos,
c->landmark[j], sz);
zfputs(buf, fp);
}
cram_free_slice(s);
}
cpos = htell(fd->fp);
assert(cpos == hpos + c->length);
cram_free_container(c);
}
if (fd->err) {
zfclose(fp);
return -1;
}
return zfclose(fp);
}
/*
* Reads a version 3 CRAM file and replaces the header in-place,
* provided the header is small enough to fit without growing the
* entire file.
*
* Version 3 format has a SAM header held as an (optionally)
* compressed block within the header container. Additional
* uncompressed blocks or simply unallocated space (the difference
* between total block sizes and the container size) are used to
* provide room for growth or contraction of the compressed header.
*
* Returns 0 on success;
* -1 on general failure;
* -2 on failure due to insufficient size
*/
int cram_reheader_inplace3(cram_fd *fd, const bam_hdr_t *h, const char *arg_list,
int add_PG)
{
cram_container *c = NULL;
cram_block *b = NULL;
SAM_hdr *hdr = NULL;
off_t start, sz, end;
int container_sz, max_container_sz;
char *buf = NULL;
int ret = -1;
if (cram_major_vers(fd) < 2 ||
cram_major_vers(fd) > 3) {
fprintf(stderr, "[%s] unsupported CRAM version %d\n", __func__,
cram_major_vers(fd));
goto err;
}
if (!(hdr = sam_hdr_parse_(h->text, h->l_text)))
goto err;
if (add_PG && sam_hdr_add_PG(hdr, "samtools", "VN", samtools_version(),
arg_list ? "CL": NULL,
arg_list ? arg_list : NULL,
NULL))
goto err;
int header_len = sam_hdr_length(hdr);
/* Fix M5 strings? Maybe out of scope for this tool */
// Find current size of SAM header block
if ((start = hseek(cram_fd_get_fp(fd), 26, SEEK_SET)) != 26)
goto err;
if (!(c = cram_read_container(fd)))
goto err;
// +5 allows num_landmarks to increase from 0 to 1 (Cramtools)
max_container_sz = cram_container_size(c)+5;
sz = htell(cram_fd_get_fp(fd)) + cram_container_get_length(c) - start;
end = htell(cram_fd_get_fp(fd)) + cram_container_get_length(c);
// We force 1 block instead of (optionally) 2. C CRAM
// implementations for v3 were writing 1 compressed block followed
// by 1 uncompressed block. However this is tricky to deal with
// as changing block sizes can mean the block header also changes
// size due to itf8 and variable size integers.
//
// If we had 1 block, this doesn't change anything.
// If we had 2 blocks, the new container header will be smaller by
// 1+ bytes, requiring the cram_container_get_length(c) to be larger in value.
// However this is an int32 instead of itf8 so the container
// header structure stays the same size. This means we can always
// reduce the number of blocks without running into size problems.
cram_container_set_num_blocks(c, 1);
int32_t *landmark;
int32_t num_landmarks;
landmark = cram_container_get_landmarks(c, &num_landmarks);
if (num_landmarks && landmark) {
num_landmarks = 1;
landmark[0] = 0;
} else {
num_landmarks = 0;
}
cram_container_set_landmarks(c, num_landmarks, landmark);
buf = malloc(max_container_sz);
container_sz = max_container_sz;
if (cram_store_container(fd, c, buf, &container_sz) != 0)
goto err;
if (!buf)
goto err;
// Proposed new length, but changing cram_container_get_length(c) may change the
// container_sz and thus the remainder (cram_container_get_length(c) itself).
cram_container_set_length(c, sz - container_sz);
int old_container_sz = container_sz;
container_sz = max_container_sz;
if (cram_store_container(fd, c, buf, &container_sz) != 0)
goto err;
if (old_container_sz != container_sz) {
fprintf(stderr, "Quirk of fate makes this troublesome! "
"Please use non-inplace version.\n");
goto err;
}
// Version 3.0 supports compressed header
b = cram_new_block(FILE_HEADER, 0);
int32_put_blk(b, header_len);
cram_block_append(b, sam_hdr_str(hdr), header_len);
cram_block_update_size(b);
cram_compress_block(fd, b, NULL, -1, -1);
if (hseek(cram_fd_get_fp(fd), 26, SEEK_SET) != 26)
goto err;
if (cram_block_size(b) > cram_container_get_length(c)) {
fprintf(stderr, "New header will not fit. Use non-inplace version"
" (%d > %d)\n",
(int)cram_block_size(b), cram_container_get_length(c));
ret = -2;
goto err;
}
if (cram_write_container(fd, c) == -1)
goto err;
if (cram_write_block(fd, b) == -1)
goto err;
// Blank out the remainder
int rsz = end - htell(cram_fd_get_fp(fd));
assert(rsz >= 0);
if (rsz) {
char *rem = calloc(1, rsz);
ret = hwrite(cram_fd_get_fp(fd), rem, rsz) == rsz ? 0 : -1;
free(rem);
}
err:
if (c) cram_free_container(c);
if (buf) free(buf);
if (b) cram_free_block(b);
if (hdr) sam_hdr_free(hdr);
return ret;
}
