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gfa-io.c
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#include <zlib.h>
#include <stdio.h>
#include <stdlib.h>
#include <ctype.h>
#include <string.h>
#include "kstring.h"
#include "gfa-priv.h"
#include <cassert>
#include "kseq.h"
KSTREAM_INIT(gzFile, gzread, 65536)
/***********
* Tag I/O *
***********/
static inline int gfa_aux_type2size(int x)
{
if (x == 'C' || x == 'c' || x == 'A') return 1;
else if (x == 'S' || x == 's') return 2;
else if (x == 'I' || x == 'i' || x == 'f') return 4;
else return 0;
}
#define __skip_tag(s) do { \
int type = *(s); \
++(s); \
if (type == 'Z') { while (*(s)) ++(s); ++(s); } \
else if (type == 'B') (s) += 5 + gfa_aux_type2size(*(s)) * (*(int32_t*)((s)+1)); \
else (s) += gfa_aux_type2size(type); \
} while(0)
uint8_t *gfa_aux_next(int32_t *l_rest, uint8_t **rest)
{
uint8_t *s = (*rest) + 2, *ret = *rest;
if (*l_rest == 0) return 0;
__skip_tag(s);
*l_rest -= s - *rest;
*rest = s;
return ret;
}
void gfa_walk_flip(gfa_t *g)
{
int32_t i, j;
int8_t *strand;
if (g->n_walk == 0) return;
GFA_CALLOC(strand, g->n_seg);
for (i = 0; i < g->n_walk; ++i) {
gfa_walk_t *w = &g->walk[i];
for (j = 0; j < w->n_v; ++j)
if (strand[w->v[j]>>1] == 0)
strand[w->v[j]>>1] = w->v[j]&1? -1 : 1;
}
for (i = 0; i < g->n_walk; ++i) {
gfa_walk_t *w = &g->walk[i];
int32_t n[2];
n[0] = n[1] = 0;
for (j = 0; j < w->n_v; ++j) {
int8_t s;
assert(strand[w->v[j]>>1] != 0);
s = w->v[j]&1? -1 : 1;
if (s == strand[w->v[j]>>1]) ++n[0];
else ++n[1];
}
if (n[0] >= n[1]) continue;
for (j = 0; j < w->n_v>>1; ++j) {
uint32_t t = w->v[j]^1;
w->v[j] = w->v[w->n_v - 1 - j]^1;
w->v[w->n_v - 1 - j] = t;
}
if (w->n_v&1) w->v[w->n_v>>1] ^= 1;
if (w->aux.l_aux > 0) { // reverse array tags
int32_t l_rest = w->aux.l_aux;
uint8_t *t, *rest = w->aux.aux;
while ((t = gfa_aux_next(&l_rest, &rest)) != 0) {
if (t[2] == 'B') {
int32_t ts, n;
ts = gfa_aux_type2size(t[3]);
memcpy(&n, t + 4, 4);
if (n == w->n_v) { // same size as the number of vertices
uint8_t buf[8];
for (j = 0; j < w->n_v>>1; ++j) {
memcpy(buf, t + 8 + j * ts, ts);
memcpy(t + 8 + j * ts, t + 8 + (w->n_v - 1 - j) * ts, ts);
memcpy(t + 8 + (w->n_v - 1 - j) * ts, buf, ts);
}
}
}
}
}
}
free(strand);
}
int gfa_aux_parse(char *s, uint8_t **data, int *max)
{
char *q, *p;
kstring_t str;
if (s == 0) return 0;
str.l = 0, str.m = *max, str.s = (char*)*data;
if (*s == '\t') ++s;
for (p = q = s;; ++p) {
if (*p == 0 || *p == '\t') {
int c = *p;
*p = 0;
if (p - q >= 5 && q[2] == ':' && q[4] == ':' && (q[3] == 'A' || q[3] == 'i' || q[3] == 'f' || q[3] == 'Z' || q[3] == 'B')) {
int type = q[3];
kputsn_(q, 2, &str);
q += 5;
if (type == 'A') {
kputc_('A', &str);
kputc_(*q, &str);
} else if (type == 'i') {
int32_t x;
x = strtol(q, &q, 10);
kputc_(type, &str); kputsn_((char*)&x, 4, &str);
} else if (type == 'f') {
float x;
x = strtod(q, &q);
kputc_('f', &str); kputsn_(&x, 4, &str);
} else if (type == 'Z') {
kputc_('Z', &str); kputsn_(q, p - q + 1, &str); // note that this include the trailing NULL
} else if (type == 'B') {
type = *q++; // q points to the first ',' following the typing byte
if (p - q >= 2 && (type == 'c' || type == 'C' || type == 's' || type == 'S' || type == 'i' || type == 'I' || type != 'f')) {
int32_t n;
char *r;
for (r = q, n = 0; *r; ++r)
if (*r == ',') ++n;
kputc_('B', &str); kputc_(type, &str); kputsn_(&n, 4, &str);
// TODO: to evaluate which is faster: a) aligned array and then memmove(); b) unaligned array; c) kputsn_()
if (type == 'c') while (q + 1 < p) { int8_t x = strtol(q + 1, &q, 0); kputc_(x, &str); }
else if (type == 'C') while (q + 1 < p) { uint8_t x = strtol(q + 1, &q, 0); kputc_(x, &str); }
else if (type == 's') while (q + 1 < p) { int16_t x = strtol(q + 1, &q, 0); kputsn_(&x, 2, &str); }
else if (type == 'S') while (q + 1 < p) { uint16_t x = strtol(q + 1, &q, 0); kputsn_(&x, 2, &str); }
else if (type == 'i') while (q + 1 < p) { int32_t x = strtol(q + 1, &q, 0); kputsn_(&x, 4, &str); }
else if (type == 'I') while (q + 1 < p) { uint32_t x = strtol(q + 1, &q, 0); kputsn_(&x, 4, &str); }
else if (type == 'f') while (q + 1 < p) { float x = strtod(q + 1, &q); kputsn_(&x, 4, &str); }
}
} // should not be here, as we have tested all types
}
q = p + 1;
if (c == 0) break;
}
}
if (str.l > 0 && str.l == str.m) ks_resize(&str, str.l + 1);
if (str.s) str.s[str.l] = 0;
*max = str.m, *data = (uint8_t*)str.s;
return str.l;
}
int gfa_aux_format(int l_aux, const uint8_t *aux, char **t, int *max)
{
kstring_t str;
const uint8_t *s = aux;
str.l = 0, str.s = *t, str.m = *max;
while (s < aux + l_aux) {
uint8_t type, key[2];
key[0] = s[0]; key[1] = s[1];
s += 2; type = *s++;
kputc('\t', &str); kputsn((char*)key, 2, &str); kputc(':', &str);
if (type == 'A') { kputsn("A:", 2, &str); kputc(*s, &str); ++s; }
else if (type == 'i') { kputsn("i:", 2, &str); kputw(*(int32_t*)s, &str); s += 4; }
else if (type == 'f') { ksprintf(&str, "f:%g", *(float*)s); s += 4; }
else if (type == 'Z') { kputc(type, &str); kputc(':', &str); while (*s) kputc(*s++, &str); ++s; }
else if (type == 'B') {
uint8_t sub_type = *(s++);
int32_t i, n;
memcpy(&n, s, 4);
s += 4; // no point to the start of the array
kputsn("B:", 2, &str); kputc(sub_type, &str); // write the typing
for (i = 0; i < n; ++i) { // FIXME: for better performance, put the loop after "if"
kputc(',', &str);
if ('c' == sub_type) { kputw(*(int8_t*)s, &str); ++s; }
else if ('C' == sub_type) { kputw(*(uint8_t*)s, &str); ++s; }
else if ('s' == sub_type) { kputw(*(int16_t*)s, &str); s += 2; }
else if ('S' == sub_type) { kputw(*(uint16_t*)s, &str); s += 2; }
else if ('i' == sub_type) { kputw(*(int32_t*)s, &str); s += 4; }
else if ('I' == sub_type) { kputuw(*(uint32_t*)s, &str); s += 4; }
else if ('f' == sub_type) { ksprintf(&str, "%g", *(float*)s); s += 4; }
}
}
}
*t = str.s, *max = str.m;
return str.l;
}
/****************
* Line parsers *
****************/
int gfa_parse_S(gfa_t *g, char *s)
{
int i, is_ok = 0;
char *p, *q, *seg = 0, *seq = 0, *rest = 0;
uint32_t sid, len = 0;
for (i = 0, p = q = s + 2;; ++p) {
if (*p == 0 || *p == '\t') {
int c = *p;
*p = 0;
if (i == 0) seg = q;
else if (i == 1) {
seq = q[0] == '*'? 0 : gfa_strdup(q);
is_ok = 1, rest = c? p + 1 : 0;
break;
}
++i, q = p + 1;
if (c == 0) break;
}
}
if (is_ok) { // all mandatory fields read
int l_aux, m_aux = 0, LN = -1;
uint8_t *aux = 0, *s_LN = 0;
gfa_seg_t *s;
l_aux = gfa_aux_parse(rest, &aux, &m_aux); // parse optional tags
s_LN = l_aux? gfa_aux_get(l_aux, aux, "LN") : 0;
if (s_LN && s_LN[0] == 'i') {
LN = *(int32_t*)(s_LN + 1);
l_aux = gfa_aux_del(l_aux, aux, s_LN);
}
if (seq == 0) {
if (LN >= 0) len = LN;
} else len = strlen(seq);
if (LN >= 0 && len != LN && gfa_verbose >= 2)
fprintf(stderr, "[W] for segment '%s', LN:i:%d tag is different from sequence length %d\n", seg, LN, len);
sid = gfa_add_seg(g, seg);
s = &g->seg[sid];
s->len = len, s->seq = seq;
if (l_aux > 0) {
uint8_t *s_SN = 0, *s_SO = 0, *s_SR = 0;
s_SN = gfa_aux_get(l_aux, aux, "SN");
if (s_SN && *s_SN == 'Z') { // then parse stable tags
s->snid = gfa_sseq_add(g, (char*)(s_SN + 1)), s->soff = 0;
l_aux = gfa_aux_del(l_aux, aux, s_SN);
s_SO = gfa_aux_get(l_aux, aux, "SO");
if (s_SO && *s_SO == 'i') {
s->soff = *(int32_t*)(s_SO + 1);
l_aux = gfa_aux_del(l_aux, aux, s_SO);
}
}
s_SR = gfa_aux_get(l_aux, aux, "SR");
if (s_SR && *s_SR == 'i') {
s->rank = *(int32_t*)(s_SR + 1);
if (s->rank > g->max_rank) g->max_rank = s->rank;
l_aux = gfa_aux_del(l_aux, aux, s_SR);
}
gfa_sseq_update(g, s);
}
if (l_aux > 0)
s->aux.m_aux = m_aux, s->aux.l_aux = l_aux, s->aux.aux = aux;
else if (aux)
free(aux);
} else return -1;
return 0;
}
int gfa_parse_L(gfa_t *g, char *s)
{
int i, oriv = -1, oriw = -1, is_ok = 0;
char *p, *q, *segv = 0, *segw = 0, *rest = 0;
int32_t ov = INT32_MAX, ow = INT32_MAX;
for (i = 0, p = q = s + 2;; ++p) {
if (*p == 0 || *p == '\t') {
int c = *p;
*p = 0;
if (i == 0) {
segv = q;
} else if (i == 1) {
if (*q != '+' && *q != '-') return -2;
oriv = (*q != '+');
} else if (i == 2) {
segw = q;
} else if (i == 3) {
if (*q != '+' && *q != '-') return -2;
oriw = (*q != '+');
} else if (i == 4) {
if (*q == '*') {
ov = ow = 0;
} else if (*q == ':') {
ov = INT32_MAX;
ow = isdigit(*(q+1))? strtol(q+1, &q, 10) : INT32_MAX;
} else if (isdigit(*q)) {
char *r;
ov = strtol(q, &r, 10);
if (isupper(*r)) { // CIGAR
ov = ow = 0;
do {
long l;
l = strtol(q, &q, 10);
if (*q == 'M' || *q == 'D' || *q == 'N') ov += l;
if (*q == 'M' || *q == 'I' || *q == 'S') ow += l;
++q;
} while (isdigit(*q));
} else if (*r == ':') { // overlap lengths
ow = isdigit(*(r+1))? strtol(r+1, &r, 10) : INT32_MAX;
} else break;
} else break;
is_ok = 1, rest = c? p + 1 : 0;
break;
}
++i, q = p + 1;
if (c == 0) break;
}
}
if (i == 4 && is_ok == 0) ov = ow = 0, is_ok = 1; // no overlap field
if (is_ok) {
uint32_t v, w;
int l_aux, m_aux = 0;
uint8_t *aux = 0;
gfa_arc_t *arc;
v = gfa_add_seg(g, segv) << 1 | oriv;
w = gfa_add_seg(g, segw) << 1 | oriw;
arc = gfa_add_arc1(g, v, w, ov, ow, -1, 0);
l_aux = gfa_aux_parse(rest, &aux, &m_aux); // parse optional tags
if (l_aux) {
gfa_aux_t *a = &g->link_aux[arc->link_id];
uint8_t *s_L1, *s_L2, *s_SR;
a->l_aux = l_aux, a->m_aux = m_aux, a->aux = aux;
s_SR = gfa_aux_get(a->l_aux, a->aux, "SR");
if (s_SR && s_SR[0] == 'i') {
arc->rank = *(int32_t*)(s_SR+1);
a->l_aux = gfa_aux_del(a->l_aux, a->aux, s_SR);
}
s_L1 = gfa_aux_get(a->l_aux, a->aux, "L1");
if (s_L1) {
if (ov != INT32_MAX && s_L1[0] == 'i')
g->seg[v>>1].len = g->seg[v>>1].len > ov + *(int32_t*)(s_L1+1)? g->seg[v>>1].len : ov + *(int32_t*)(s_L1+1);
a->l_aux = gfa_aux_del(a->l_aux, a->aux, s_L1);
}
s_L2 = gfa_aux_get(a->l_aux, a->aux, "L2");
if (s_L2) {
if (ow != INT32_MAX && s_L2[0] == 'i')
g->seg[w>>1].len = g->seg[w>>1].len > ow + *(int32_t*)(s_L2+1)? g->seg[w>>1].len : ow + *(int32_t*)(s_L2+1);
a->l_aux = gfa_aux_del(a->l_aux, a->aux, s_L2);
}
if (a->l_aux == 0) {
free(a->aux);
a->aux = 0, a->m_aux = 0;
}
}
} else return -1;
return 0;
}
int gfa_parse_W(gfa_t *g, char *s)
{
char *p, *q, *ctg = 0, *sample = 0;
int32_t i, is_ok = 0;
char *rest;
gfa_walk_t t;
GFA_BZERO(&t, 1);
for (p = q = s + 2, i = 0;; ++p) {
t.sample = 0;
if (*p == 0 || *p == '\t') {
int32_t c = *p;
*p = 0;
if (i == 0) {
sample = q;
} else if (i == 1) {
t.hap = atoi(q);
} else if (i == 2) {
ctg = q;
} else if (i == 3) {
t.st = atol(q);
} else if (i == 4) {
t.en = atol(q);
} else if (i == 5) {
char *pp, *qq;
for (pp = q, t.n_v = 0; pp < p; ++pp)
if (*pp == '>' || *pp == '<')
t.n_v++;
GFA_MALLOC(t.v, t.n_v);
for (qq = q, pp = q + 1, t.n_v = 0; pp <= p; ++pp) {
if (pp == p || *pp == '>' || *pp == '<') {
int32_t a = *pp, seg;
*pp = 0;
seg = gfa_name2id(g, qq + 1);
if (seg >= 0) {
t.v[t.n_v++] = (uint32_t)seg<<1 | (*qq == '<');
} else {
if (gfa_verbose >= 2)
fprintf(stderr, "WARNING: failed to find segment '%s'\n", qq + 1);
}
*pp = a, qq = pp;
}
}
is_ok = 1, rest = c? p + 1 : 0;
break;
}
q = p + 1, ++i;
if (c == 0) break;
}
}
if (is_ok) {
int l_aux, m_aux = 0;
uint8_t *aux = 0;
l_aux = gfa_aux_parse(rest, &aux, &m_aux); // parse optional tags
t.sample = (char *)malloc((strlen(sample)+1)*sizeof(char));
// t.sample = gfa_sample_add(g, sample);
strcpy(t.sample, sample);
t.snid = gfa_sseq_add(g, ctg);
if (l_aux > 0)
t.aux.m_aux = m_aux, t.aux.l_aux = l_aux, t.aux.aux = aux;
else if (aux)
free(aux);
GFA_GROW(gfa_walk_t, g->walk, g->n_walk, g->m_walk);
g->walk[g->n_walk++] = t;
} else return -1;
return 0;
}
static gfa_seg_t *gfa_parse_fa_hdr(gfa_t *g, char *s)
{
int32_t i;
char buf[16];
gfa_seg_t *seg;
for (i = 0; s[i]; ++i)
if (isspace(s[i])) break;
s[i] = 0;
sprintf(buf, "s%d", g->n_seg + 1);
i = gfa_add_seg(g, buf);
seg = &g->seg[i];
seg->snid = gfa_sseq_add(g, s + 1);
seg->soff = seg->rank = 0;
return seg;
}
static void gfa_update_fa_seq(gfa_t *g, gfa_seg_t *seg, int32_t l_seq, const char *seq)
{
if (seg == 0) return;
seg->seq = gfa_strdup(seq);
seg->len = l_seq;
gfa_sseq_update(g, seg);
}
/****************
* User-end I/O *
****************/
gfa_t *gfa_read(const char *fn)
{
gzFile fp;
gfa_t *g;
kstring_t s = {0,0,0}, fa_seq = {0,0,0};
kstream_t *ks;
int dret, is_fa = 0;
gfa_seg_t *fa_seg = 0;
uint64_t lineno = 0;
fp = fn && strcmp(fn, "-")? gzopen(fn, "r") : gzdopen(0, "r");
if (fp == 0) return 0;
ks = ks_init(fp);
g = gfa_init();
while (ks_getuntil(ks, KS_SEP_LINE, &s, &dret) >= 0) {
int ret = 0;
++lineno;
if (s.l > 0 && s.s[0] == '>') { // FASTA header
is_fa = 1;
if (fa_seg) gfa_update_fa_seq(g, fa_seg, fa_seq.l, fa_seq.s);
fa_seg = gfa_parse_fa_hdr(g, s.s);
fa_seq.l = 0;
} else if (is_fa) { // FASTA mode
if (s.l >= 3 && s.s[1] == '\t') { // likely a GFA line
gfa_update_fa_seq(g, fa_seg, fa_seq.l, fa_seq.s); // finalize fa_seg
fa_seg = 0;
is_fa = 0;
} else kputsn(s.s, s.l, &fa_seq); // likely a FASTA sequence line
}
if (is_fa) continue;
if (s.l < 3 || s.s[1] != '\t') continue; // empty line
if (s.s[0] == 'S') ret = gfa_parse_S(g, s.s);
else if (s.s[0] == 'L') ret = gfa_parse_L(g, s.s);
else if (s.s[0] == 'W') ret = gfa_parse_W(g, s.s);
if (ret < 0 && gfa_verbose >= 1)
fprintf(stderr, "[E] invalid %c-line at line %ld (error code %d)\n", s.s[0], (long)lineno, ret);
}
if (is_fa && fa_seg) gfa_update_fa_seq(g, fa_seg, fa_seq.l, fa_seq.s);
// Flip the wals
gfa_walk_flip(g);
free(fa_seq.s);
free(s.s);
gfa_finalize(g);
ks_destroy(ks);
gzclose(fp);
return g;
}
void gfa_print(const gfa_t *g, FILE *fp, int flag)
{
uint32_t i;
uint64_t k;
for (i = 0; i < g->n_seg; ++i) {
const gfa_seg_t *s = &g->seg[i];
if (s->del) continue;
fprintf(fp, "S\t%s\t", s->name);
if (s->seq && !(flag & GFA_O_NO_SEQ)) fputs(s->seq, fp);
else fputc('*', fp);
fprintf(fp, "\tLN:i:%d", s->len);
if (s->snid >= 0 && s->soff >= 0)
fprintf(fp, "\tSN:Z:%s\tSO:i:%d", g->sseq[s->snid].name, s->soff);
if (s->rank >= 0)
fprintf(fp, "\tSR:i:%d", s->rank);
if (s->utg && s->utg->n) fprintf(fp, "\tRC:i:%d\tlc:i:%d", s->utg->n, s->utg->len_comp);
if (s->aux.l_aux > 0) {
char *t = 0;
int max = 0;
gfa_aux_format(s->aux.l_aux, s->aux.aux, &t, &max);
fputs(t, fp);
free(t);
}
fputc('\n', fp);
if (s->utg && s->utg->n) {
uint32_t j, l;
for (j = l = 0; j < s->utg->n; ++j) {
const gfa_utg_t *u = s->utg;
fprintf(fp, "A\t%s\t%d\t%c\t%s\t%d\t%d\n", s->name, l, "+-"[u->a[j]>>32&1], u->name[j], (int32_t)(u->r[j]>>32), (int32_t)u->r[j]);
l += (uint32_t)u->a[j];
}
}
}
for (k = 0; k < g->n_arc; ++k) {
const gfa_arc_t *a = &g->arc[k];
const gfa_aux_t *aux = a->link_id < g->n_arc? &g->link_aux[a->link_id] : 0;
if (a->del || a->comp) continue;
fprintf(fp, "L\t%s\t%c\t%s\t%c", g->seg[a->v_lv>>33].name, "+-"[a->v_lv>>32&1], g->seg[a->w>>1].name, "+-"[a->w&1]);
if (!(flag & GFA_O_OV_EXT)) {
fprintf(fp, "\t%dM", a->ov < a->ow? a->ov : a->ow);
} else {
if (a->ov == a->ow) fprintf(fp, "\t%dM", a->ov);
else fprintf(fp, "\t%d:%d", a->ov, a->ow);
}
if (a->rank >= 0) fprintf(fp, "\tSR:i:%d", a->rank);
fprintf(fp, "\tL1:i:%d", gfa_arc_len(*a));
fprintf(fp, "\tL2:i:%d", gfa_arc_lw(g, *a));
if (aux && aux->l_aux) {
char *t = 0;
int max = 0;
gfa_aux_format(aux->l_aux, aux->aux, &t, &max);
if (t) fputs(t, fp);
free(t);
}
fputc('\n', fp);
}
}