/* bamFile -- interface to binary alignment format files using Heng Li's samtools lib. */

#include "common.h"
#include "portable.h"
#include "bamFile.h"
#ifdef USE_BAM
#include "htmshell.h"
#include "udc.h"

#ifndef KNETFILE_HOOKS
static char *getSamDir()
/* Return the name of a trash dir for samtools to run in (it creates files in current dir)
 * and make sure the directory exists. */
{
static char *samDir = NULL;
char *dirName = "samtools";
if (samDir == NULL)
    {
    mkdirTrashDirectory(dirName);
    size_t len = strlen(trashDir()) + 1 + strlen(dirName) + 1;
    samDir = needMem(len);
    safef(samDir, len, "%s/%s", trashDir(), dirName);
    }
return samDir;
}
#endif//ndef KNETFILE_HOOKS

boolean bamFileExists(char *fileOrUrl)
/* Return TRUE if we can successfully open the bam file and its index file. */
{
char *bamFileName = fileOrUrl;
samfile_t *fh = samopen(bamFileName, "rb", NULL);
boolean usingUrl = TRUE; 
usingUrl = (strstr(fileOrUrl, "tp://") || strstr(fileOrUrl, "https://"));
if (fh != NULL)
    {
#ifndef KNETFILE_HOOKS
    // When file is an URL, this caches the index file in addition to validating:
    // Since samtools's url-handling code saves the .bai file to the current directory,
    // chdir to a trash directory before calling bam_index_load, then chdir back.
    char *runDir = getCurrentDir();
    char *samDir = getSamDir();
    if (usingUrl)
	setCurrentDir(samDir);
#endif//ndef KNETFILE_HOOKS
    bam_index_t *idx = bam_index_load(bamFileName);
#ifndef KNETFILE_HOOKS
    if (usingUrl)
	setCurrentDir(runDir);
#endif//ndef KNETFILE_HOOKS
    samclose(fh);
    if (idx == NULL)
	{
	warn("bamFileExists: failed to read index corresponding to %s", bamFileName);
	return FALSE;
	}
    free(idx); // Not freeMem, freez etc -- sam just uses malloc/calloc.
    return TRUE;
    }
return FALSE;
}

samfile_t *bamOpen(char *fileOrUrl, char **retBamFileName)
/* Return an open bam file, dealing with FUSE caching if need be. 
 * Return parameter if NON-null will return the file name after FUSing */
{
char *bamFileName = fileOrUrl;
if (retBamFileName != NULL)
    *retBamFileName = bamFileName;

#ifdef BAM_VERSION
// suppress too verbose messages in samtools >= 0.1.18; see redmine #6491
// This variable didn't exist in older versions of samtools (where BAM_VERSION wasn't defined).
bam_verbose = 1;
#endif

samfile_t *fh = samopen(bamFileName, "rb", NULL);
if (fh == NULL)
    {
    boolean usingUrl = (strstr(fileOrUrl, "tp://") || strstr(fileOrUrl, "https://"));
    struct dyString *urlWarning = dyStringNew(0);
    if (usingUrl)
	{
	dyStringAppend(urlWarning,
		       ". If you are able to access the URL with your web browser, "
		       "please try reloading this page.");
	}
    errAbort("Failed to open %s%s", fileOrUrl, urlWarning->string);
    }
return fh;
}

void bamClose(samfile_t **pSamFile)
/* Close down a samefile_t */
{
if (pSamFile != NULL)
    {
    samclose(*pSamFile);
    *pSamFile = NULL;
    }
}

void bamFetchAlreadyOpen(samfile_t *samfile, bam_index_t *idx, char *bamFileName, 
			 char *position, bam_fetch_f callbackFunc, void *callbackData)
/* With the open bam file, return items the same way with the callbacks as with bamFetch() */
/* except in this case use an already-open bam file and index (use bam_index_load and free() for */
/* the index). It seems a little strange to pass the filename in with the open bam, but */
/* it's just used to report errors. */
{
int chromId, start, end;
int ret = bam_parse_region(samfile->header, position, &chromId, &start, &end);
if (ret != 0 && startsWith("chr", position))
    ret = bam_parse_region(samfile->header, position+strlen("chr"), &chromId, &start, &end);
if (ret != 0)
    // If the bam file does not cover the current chromosome, OK
    return;
ret = bam_fetch(samfile->x.bam, idx, chromId, start, end, callbackData, callbackFunc);
if (ret != 0)
    warn("bam_fetch(%s, %s (chromId=%d) failed (%d)", bamFileName, position, chromId, ret);
}

void bamFetch(char *fileOrUrl, char *position, bam_fetch_f callbackFunc, void *callbackData,
		 samfile_t **pSamFile)
/* Open the .bam file, fetch items in the seq:start-end position range,
 * and call callbackFunc on each bam item retrieved from the file plus callbackData.
 * This handles BAM files with "chr"-less sequence names, e.g. from Ensembl. 
 * The pSamFile parameter is optional.  If non-NULL it will be filled in, just for
 * the benefit of the callback function, with the open samFile.  */
{
char *bamFileName = NULL;
samfile_t *fh = bamOpen(fileOrUrl, &bamFileName);
boolean usingUrl = TRUE;
usingUrl = (strstr(fileOrUrl, "tp://") || strstr(fileOrUrl, "https://"));
if (pSamFile != NULL)
    *pSamFile = fh;
#ifndef KNETFILE_HOOKS
// Since samtools' url-handling code saves the .bai file to the current directory,
// chdir to a trash directory before calling bam_index_load, then chdir back.
char *runDir = getCurrentDir();
char *samDir = getSamDir();
if (usingUrl)
    setCurrentDir(samDir);
#endif//ndef KNETFILE_HOOKS
bam_index_t *idx = bam_index_load(bamFileName);
#ifndef KNETFILE_HOOKS
if (usingUrl)
    setCurrentDir(runDir);
#endif//ndef KNETFILE_HOOKS
if (idx == NULL)
    warn("bam_index_load(%s) failed.", bamFileName);
else
    {
    bamFetchAlreadyOpen(fh, idx, bamFileName, position, callbackFunc, callbackData);
    free(idx); // Not freeMem, freez etc -- sam just uses malloc/calloc.
    }
bamClose(&fh);
}

boolean bamIsRc(const bam1_t *bam)
/* Return TRUE if alignment is on - strand. */
{
const bam1_core_t *core = &bam->core;
return (core->flag & BAM_FREVERSE);
}

void bamGetSoftClipping(const bam1_t *bam, int *retLow, int *retHigh, int *retClippedQLen)
/* If retLow is non-NULL, set it to the number of "soft-clipped" (skipped) bases at
 * the beginning of the query sequence and quality; likewise for retHigh at end.
 * For convenience, retClippedQLen is the original query length minus soft clipping
 * (and the length of the query sequence that will be returned). */
{
unsigned int *cigarPacked = bam1_cigar(bam);
const bam1_core_t *core = &bam->core;
char op;
int n = bamUnpackCigarElement(cigarPacked[0], &op);
int low = (op == 'S') ? n : 0;
n = bamUnpackCigarElement(cigarPacked[core->n_cigar-1], &op);
int high = (op == 'S') ? n : 0;
if (retLow != NULL)
    *retLow = low;
if (retHigh != NULL)
    *retHigh = high;
if (retClippedQLen != NULL)
    *retClippedQLen = (core->l_qseq - low - high);
}


void bamUnpackQuerySequence(const bam1_t *bam, boolean useStrand, char *qSeq)
/* Fill in qSeq with the nucleotide sequence encoded in bam.  The BAM format 
 * reverse-complements query sequence when the alignment is on the - strand,
 * so if useStrand is given we rev-comp it back to restore the original query 
 * sequence. */
{
const bam1_core_t *core = &bam->core;
int qLen = core->l_qseq;
uint8_t *packedQSeq = bam1_seq(bam);
int i;
for (i = 0; i < qLen; i++)
    qSeq[i] = bam_nt16_rev_table[bam1_seqi(packedQSeq, i)];
qSeq[i] = '\0';
if (useStrand && bamIsRc(bam))
    reverseComplement(qSeq, qLen);
}

char *bamGetQuerySequence(const bam1_t *bam, boolean useStrand)
/* Allocate and return the nucleotide sequence encoded in bam.  The BAM format 
 * reverse-complements query sequence when the alignment is on the - strand,
 * so if useStrand is given we rev-comp it back to restore the original query 
 * sequence. */
{
const bam1_core_t *core = &bam->core;
int qLen = core->l_qseq;
char *qSeq = needMem(qLen+1);
bamUnpackQuerySequence(bam, useStrand, qSeq);
return qSeq;
}

UBYTE *bamGetQueryQuals(const bam1_t *bam, boolean useStrand)
/* Return the base quality scores encoded in bam as an array of ubytes. */
{
const bam1_core_t *core = &bam->core;
int qLen = core->l_qseq;
UBYTE *arr = needMem(qLen);
boolean isRc = useStrand && bamIsRc(bam);
UBYTE *qualStr = bam1_qual(bam);
int i;
for (i = 0;  i < core->l_qseq;  i++)
    {
    int offset = isRc ? (qLen - 1 - i) : i;
    arr[i] = (qualStr[0] == 255) ? 255 : qualStr[offset];
    }
return arr;
}

void bamUnpackCigar(const bam1_t *bam, struct dyString *dyCigar)
/* Unpack CIGAR string into dynamic string */
{
unsigned int *cigarPacked = bam1_cigar(bam);
const bam1_core_t *core = &bam->core;
int i;
for (i = 0;  i < core->n_cigar;  i++)
    {
    char op;
    int n = bamUnpackCigarElement(cigarPacked[i], &op);
    dyStringPrintf(dyCigar, "%d", n);
    dyStringAppendC(dyCigar, op);
    }
}

char *bamGetCigar(const bam1_t *bam)
/* Return a BAM-enhanced CIGAR string, decoded from the packed encoding in bam. */
{
const bam1_core_t *core = &bam->core;
struct dyString *dyCigar = dyStringNew(min(8, core->n_cigar*4));
bamUnpackCigar(bam, dyCigar);
return dyStringCannibalize(&dyCigar);
}

void bamShowCigarEnglish(const bam1_t *bam)
/* Print out cigar in English e.g. "20 (mis)Match, 1 Deletion, 3 (mis)Match" */
{
unsigned int *cigarPacked = bam1_cigar(bam);
const bam1_core_t *core = &bam->core;
int i;
for (i = 0;  i < core->n_cigar;  i++)
    {
    char op;
    int n = bamUnpackCigarElement(cigarPacked[i], &op);
    if (i > 0)
	printf(", ");
    switch (op)
	{
	case 'M': // match or mismatch (gapless aligned block)
	    printf("%d (mis)Match", n);
	    break;
	case '=': // match
	    printf("%d Match", n);
	    break;
	case 'X': // mismatch
	    printf("%d Mismatch", n);
	    break;
	case 'I': // inserted in query
	    printf("%d Insertion", n);
	    break;
	case 'S': // skipped query bases at beginning or end ("soft clipping")
	    printf("%d Skipped", n);
	    break;
	case 'D': // deleted from query
	    printf("%d Deletion", n);
	    break;
	case 'N': // long deletion from query (intron as opposed to small del)
	    printf("%d deletioN", n);
	    break;
	case 'H': // skipped query bases not stored in record's query sequence ("hard clipping")
	    printf("%d Hard clipped query", n);
	    break;
	case 'P': // P="silent deletion from padded reference sequence"
	    printf("%d Padded / silent deletion", n);
	    break;
	default:
	    errAbort("bamShowCigarEnglish: unrecognized CIGAR op %c -- update me", op);
	}
    }
}

static void descFlag(unsigned flag, unsigned bitMask, char *desc, boolean makeRed,
	      boolean *retFirst)
/* Describe a flag bit (or multi-bit mask) if it is set in flag. */
{
if ((flag & bitMask) == bitMask) // *all* bits in bitMask are set in flag
    {
    if (!*retFirst)
	printf(" | ");
    printf("<span%s>(<TT>0x%02x</TT>) %s</span>",
	   (makeRed ? " style='color: red'" : ""), bitMask, desc);
    *retFirst = FALSE;
    }
}

void bamShowFlagsEnglish(const bam1_t *bam)
/* Print out flags in English, e.g. "Mate is on '-' strand; Properly paired". */
{
const bam1_core_t *core = &bam->core;
unsigned flag = core->flag;
boolean first = TRUE;
descFlag(flag, BAM_FDUP, "Optical or PCR duplicate", TRUE, &first);
descFlag(flag, BAM_FQCFAIL, "QC failure", TRUE, &first);
descFlag(flag, BAM_FSECONDARY, "Not primary alignment", TRUE, &first);
descFlag(flag, BAM_FREAD2, "Read 2 of pair", FALSE, &first);
descFlag(flag, BAM_FREAD1, "Read 1 of pair", FALSE, &first);
descFlag(flag, BAM_FMREVERSE, "Mate is on '-' strand", FALSE, &first);
descFlag(flag, BAM_FREVERSE, "Read is on '-' strand", FALSE, &first);
descFlag(flag, BAM_FMUNMAP, "Mate is unmapped", TRUE, &first);
if (flag & BAM_FUNMAP)
    errAbort("Read is unmapped (what is it doing here?!?)");
descFlag(flag, (BAM_FPROPER_PAIR | BAM_FPAIRED), "Properly paired", FALSE, &first);
if ((flag & BAM_FPAIRED) && !(flag & BAM_FPROPER_PAIR))
    descFlag(flag, BAM_FPAIRED, "Not properly paired", TRUE, &first);
}

int bamGetTargetLength(const bam1_t *bam)
/* Tally up the alignment's length on the reference sequence from
 * bam's packed-int CIGAR representation. */
{
unsigned int *cigarPacked = bam1_cigar(bam);
const bam1_core_t *core = &bam->core;
int tLength=0;
int i;
for (i = 0;  i < core->n_cigar;  i++)
    {
    char op;
    int n = bamUnpackCigarElement(cigarPacked[i], &op);
    switch (op)
	{
	case 'M': // match or mismatch (gapless aligned block)
	case '=': // match
	case 'X': // mismatch
	    tLength += n;
	    break;
	case 'I': // inserted in query
	    break;
	case 'D': // deleted from query
	case 'N': // long deletion from query (intron as opposed to small del)
	    tLength += n;
	    break;
	case 'S': // skipped query bases at beginning or end ("soft clipping")
	case 'H': // skipped query bases not stored in record's query sequence ("hard clipping")
	case 'P': // P="silent deletion from padded reference sequence" -- ignore these.
	    break;
	default:
	    errAbort("bamGetTargetLength: unrecognized CIGAR op %c -- update me", op);
	}
    }
return tLength;
}

bam1_t *bamClone(const bam1_t *bam)
/* Return a newly allocated copy of bam. */
{
// Using typecasts to get around compiler complaints about bam being const:
bam1_t *newBam = cloneMem((void *)bam, sizeof(*bam));
newBam->data = cloneMem((void *)bam->data, bam->data_len*sizeof(bam->data[0]));
return newBam;
}

void bamShowTags(const bam1_t *bam)
/* Print out tags in HTML: bold key, no type indicator for brevity. */
{
// adapted from part of bam.c bam_format1:
uint8_t *s = bam1_aux(bam);
while (s < bam->data + bam->data_len)
    {
    uint8_t type, key[2];
    key[0] = s[0]; key[1] = s[1];
    s += 2; type = *s; ++s;
    printf(" <B>%c%c</B>:", key[0], key[1]);
    if (type == 'A') { printf("%c", *s); ++s; }
    else if (type == 'C') { printf("%u", *s); ++s; }
    else if (type == 'c') { printf("%d", *(int8_t*)s); ++s; }
    else if (type == 'S') { printf("%u", *(uint16_t*)s); s += 2; }
    else if (type == 's') { printf("%d", *(int16_t*)s); s += 2; }
    else if (type == 'I') { printf("%u", *(uint32_t*)s); s += 4; }
    else if (type == 'i') { printf("%d", *(int32_t*)s); s += 4; }
    else if (type == 'f') { printf("%g", *(float*)s); s += 4; }
    else if (type == 'd') { printf("%lg", *(double*)s); s += 8; }
    else if (type == 'Z' || type == 'H')
	{
	htmTextOut(stdout, (char *)s);
	s += strlen((char *)s) + 1;
	}
    }
putc('\n', stdout);
}

char *bamGetTagString(const bam1_t *bam, char *tag, char *buf, size_t bufSize)
/* If bam's tags include the given 2-character tag, place the value into 
 * buf (zero-terminated, trunc'd if nec) and return a pointer to buf,
 * or NULL if tag is not present. */
{
if (tag == NULL)
    errAbort("NULL tag passed to bamGetTagString");
if (! (isalpha(tag[0]) && isalnum(tag[1]) && tag[2] == '\0'))
    errAbort("bamGetTagString: invalid tag '%s'", htmlEncode(tag));
char *val = NULL;
// adapted from part of bam.c bam_format1:
uint8_t *s = bam1_aux(bam);
while (s < bam->data + bam->data_len)
    {
    uint8_t type, key[2];
    key[0] = s[0]; key[1] = s[1];
    s += 2; type = *s; ++s;
    if (key[0] == tag[0] && key[1] == tag[1])
	{
	if (type == 'A') { snprintf(buf, bufSize, "%c", *s);}
	else if (type == 'C') { snprintf(buf, bufSize, "%u", *s); }
	else if (type == 'c') { snprintf(buf, bufSize, "%d", *s); }
	else if (type == 'S') { snprintf(buf, bufSize, "%u", *(uint16_t*)s); }
	else if (type == 's') { snprintf(buf, bufSize, "%d", *(int16_t*)s); }
	else if (type == 'I') { snprintf(buf, bufSize, "%u", *(uint32_t*)s); }
	else if (type == 'i') { snprintf(buf, bufSize, "%d", *(int32_t*)s); }
	else if (type == 'f') { snprintf(buf, bufSize, "%g", *(float*)s); }
	else if (type == 'd') { snprintf(buf, bufSize, "%lg", *(double*)s); }
	else if (type == 'Z' || type == 'H') strncpy(buf, (char *)s, bufSize);
	else buf[0] = '\0';
	buf[bufSize-1] = '\0'; // TODO: is this nec?? see man pages
	val = buf;
	break;
	}
    else
	{
	if (type == 'A' || type == 'C' || type == 'c') { ++s; }
	else if (type == 'S' || type == 's') { s += 2; }
	else if (type == 'I' || type == 'i' || type == 'f') { s += 4; }
	else if (type == 'd') { s += 8; }
	else if (type == 'Z' || type == 'H')
	    {
	    while (*s++);
	    }
	}
    }
return val;
}

void bamUnpackAux(const bam1_t *bam, struct dyString *dy)
/* Unpack the tag:type:val part of bam into dy */
{
// adapted from part of bam.c bam_format1:
uint8_t *s = bam1_aux(bam);
boolean firstTime = TRUE;
while (s < bam->data + bam->data_len)
    {
    if (firstTime)
        firstTime = FALSE;
    else
        dyStringAppendC(dy, '\t');
    dyStringAppendC(dy, *s++);
    dyStringAppendC(dy, *s++);
    dyStringAppendC(dy, ':');
    dyStringAppendC(dy, s[0]);
    dyStringAppendC(dy, ':');
    uint8_t type = *s++;
    if (type == 'A') { dyStringPrintf(dy, "%c", *s); ++s; }
    else if (type == 'C') { dyStringPrintf(dy, "%u", *s); ++s; }
    else if (type == 'c') { dyStringPrintf(dy, "%d", *s); ++s; }
    else if (type == 'S') { dyStringPrintf(dy, "%u", *(uint16_t*)s); s += 2; }
    else if (type == 's') { dyStringPrintf(dy, "%d", *(int16_t*)s); s += 2; }
    else if (type == 'I') { dyStringPrintf(dy, "%u", *(uint32_t*)s); s += 4; }
    else if (type == 'i') { dyStringPrintf(dy, "%d", *(int32_t*)s); s += 4; }
    else if (type == 'f') { dyStringPrintf(dy, "%g", *(float*)s); s += 4; }
    else if (type == 'd') { dyStringPrintf(dy, "%lg", *(double*)s); s += 8; }
    else if (type == 'Z' || type == 'H')
	{
	dyStringAppend(dy, (char *)s);
	s += strlen((char *)s) + 1;
	}
    }
}

struct bamChromInfo *bamChromList(samfile_t *fh)
{
/* Return list of chromosomes from bam header. We make no attempty to normalize chromosome names to UCSC format,
   so list may contain things like "1" for "chr1", "I" for "chrI", "MT" for "chrM" etc. */
int i;
struct bamChromInfo *list = NULL;
bam_header_t *bamHeader = fh->header;
if(bamHeader == NULL)
    return NULL;
for(i = 0; i < bamHeader->n_targets; i++)
    {
    struct bamChromInfo *info = NULL;
    AllocVar(info);
    info->name = cloneString(bamHeader->target_name[i]);
    info->size = bamHeader->target_len[i];
    slAddHead(&list, info);
    }
slReverse(&list);
return list;
}

#else
// If we're not compiling with samtools, make stub routines so compile won't fail:

boolean bamFileExists(char *bamFileName)
/* Return TRUE if we can successfully open the bam file and its index file. */
{
warn(COMPILE_WITH_SAMTOOLS, "bamFileExists");
return FALSE;
}

samfile_t *bamOpen(char *fileOrUrl, char **retBamFileName)
/* Return an open bam file */
{
warn(COMPILE_WITH_SAMTOOLS, "bamOpenUdc");
return FALSE;
}

void bamClose(samfile_t **pSamFile)
/* Close down a samefile_t */
{
errAbort(COMPILE_WITH_SAMTOOLS, "bamClose");
}

void bamFetch(char *fileOrUrl, char *position, bam_fetch_f callbackFunc, void *callbackData,
	      samfile_t **pSamFile)
/* Open the .bam file, fetch items in the seq:start-end position range,
 * and call callbackFunc on each bam item retrieved from the file plus callbackData.
 * This handles BAM files with "chr"-less sequence names, e.g. from Ensembl.
 * The pSamFile parameter is optional.  If non-NULL it will be filled in, just for
 * the benefit of the callback function, with the open samFile.  */
{
errAbort(COMPILE_WITH_SAMTOOLS, "bamFetch");
}

boolean bamIsRc(const bam1_t *bam)
/* Return TRUE if alignment is on - strand. */
{
errAbort(COMPILE_WITH_SAMTOOLS, "bamIsRc");
return FALSE;
}

void bamGetSoftClipping(const bam1_t *bam, int *retLow, int *retHigh, int *retClippedQLen)
/* If retLow is non-NULL, set it to the number of "soft-clipped" (skipped) bases at
 * the beginning of the query sequence and quality; likewise for retHigh at end.
 * For convenience, retClippedQLen is the original query length minus soft clipping
 * (and the length of the query sequence that will be returned). */
{
errAbort(COMPILE_WITH_SAMTOOLS, "bamGetSoftClipping");
}

char *bamGetQuerySequence(const bam1_t *bam, boolean useStrand)
/* Return the nucleotide sequence encoded in bam.  The BAM format
 * reverse-complements query sequence when the alignment is on the - strand,
 * so if useStrand is given we rev-comp it back to restore the original query
 * sequence. */
{
errAbort(COMPILE_WITH_SAMTOOLS, "bamGetQuerySequence");
return NULL;
}

UBYTE *bamGetQueryQuals(const bam1_t *bam, boolean useStrand)
/* Return the base quality scores encoded in bam as an array of ubytes. */
{
errAbort(COMPILE_WITH_SAMTOOLS, "bamGetQueryQuals");
return NULL;
}

char *bamGetCigar(const bam1_t *bam)
/* Return a BAM-enhanced CIGAR string, decoded from the packed encoding in bam. */
{
errAbort(COMPILE_WITH_SAMTOOLS, "bamGetCigar");
return NULL;
}

void bamShowCigarEnglish(const bam1_t *bam)
/* Print out cigar in English e.g. "20 (mis)Match, 1 Deletion, 3 (mis)Match" */
{
errAbort(COMPILE_WITH_SAMTOOLS, "bamShowCigarEnglish");
}

void bamShowFlagsEnglish(const bam1_t *bam)
/* Print out flags in English, e.g. "Mate is on '-' strand; Properly paired". */
{
errAbort(COMPILE_WITH_SAMTOOLS, "bamShowFlagsEnglish");
}

int bamGetTargetLength(const bam1_t *bam)
/* Tally up the alignment's length on the reference sequence from
 * bam's packed-int CIGAR representation. */
{
errAbort(COMPILE_WITH_SAMTOOLS, "bamGetTargetLength");
return 0;
}

bam1_t *bamClone(const bam1_t *bam)
/* Return a newly allocated copy of bam. */
{
errAbort(COMPILE_WITH_SAMTOOLS, "bamClone");
return NULL;
}

void bamShowTags(const bam1_t *bam)
/* Print out tags in HTML: bold key, no type indicator for brevity. */
{
errAbort(COMPILE_WITH_SAMTOOLS, "bamShowTags");
}

char *bamGetTagString(const bam1_t *bam, char *tag, char *buf, size_t bufSize)
/* If bam's tags include the given 2-character tag, place the value into
 * buf (zero-terminated, trunc'd if nec) and return a pointer to buf,
 * or NULL if tag is not present. */
{
errAbort(COMPILE_WITH_SAMTOOLS, "bamGetTagString");
return NULL;
}

struct bamChromInfo *bamChromList(samfile_t *fh)
{
errAbort(COMPILE_WITH_SAMTOOLS, "bamChromList");
return NULL;
}

#endif//ndef USE_BAM

static void bamChromInfoFree(struct bamChromInfo **pInfo)
/* Free up one chromInfo */
{
struct bamChromInfo *info = *pInfo;
if (info != NULL)
    {
    freeMem(info->name);
    freez(pInfo);
    }
}

void bamChromInfoFreeList(struct bamChromInfo **pList)
/* Free a list of dynamically allocated bamChromInfo's */
{
struct bamChromInfo *el, *next;

for (el = *pList; el != NULL; el = next)
    {
    next = el->next;
    bamChromInfoFree(&el);
    }
*pList = NULL;
}