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For open/openat, if the flags parameter does not contain O_CREAT, the
3rd (variadic) mode_t parameter is irrelevant.  Many developers in the past
have passed mode_t (0, 044, 0644, or such), which might lead future people
to copy this broken idiom, and perhaps even believe this parameter has some
meaning or implication or application. Delete them all.
This comes out of a conversation where tb@ noticed that a strange (but
intentional) pledge behaviour is to always knock-out high-bits from
mode_t on a number of system calls as a safety factor, and his bewilderment
that this appeared to be happening against valid modes (at least visually),
but no sorry, they are all irrelevant junk.  They could all be 0xdeafbeef.
ok millert

/*
 * Copyright (c) 2008-2014 Alexandre Ratchov <alex@caoua.org>
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

#include <fcntl.h>
#include <string.h>
#include <unistd.h>
#include "afile.h"
#include "utils.h"

typedef struct {
	unsigned char ld[4];
} le32_t;

typedef struct {
	unsigned char lw[2];
} le16_t;

typedef struct {
	unsigned char bd[4];
} be32_t;

typedef struct {
	unsigned char bw[2];
} be16_t;

struct wav_riff {
	char id[4];
	le32_t size;
	char type[4];
};

struct wav_chunk {
	char id[4];
	le32_t size;
};

struct wav_fmt {
#define WAV_FMT_PCM	1
#define WAV_FMT_FLOAT	3
#define WAV_FMT_ALAW	6
#define WAV_FMT_ULAW	7
#define WAV_FMT_EXT	0xfffe
	le16_t fmt;
	le16_t nch;
	le32_t rate;
	le32_t byterate;
	le16_t blkalign;
	le16_t bits;
#define WAV_FMT_SIZE		 16
#define WAV_FMT_EXT_SIZE	(16 + 24)
	le16_t extsize;
	le16_t valbits;
	le32_t chanmask;
	le16_t extfmt;
	char guid[14];
};

struct wav_hdr {
	struct wav_riff riff;		/* 00..11 */
	struct wav_chunk fmt_hdr;	/* 12..20 */
	struct wav_fmt fmt;
	struct wav_chunk data_hdr;
};

struct aiff_form {
	char id[4];
	be32_t size;
	char type[4];
};

struct aiff_chunk {
	char id[4];
	be32_t size;
};

struct aiff_comm {
	struct aiff_commbase {
		be16_t nch;
		be32_t nfr;
		be16_t bits;
		/* rate in 80-bit floating point */
		be16_t rate_ex;
		be32_t rate_hi;
		be32_t rate_lo;
	} base;
	char comp_id[4];
	/* followed by stuff we don't care about */
};

struct aiff_data {
	be32_t offs;
	be32_t blksz;
};

struct aiff_hdr {
	struct aiff_form form;
	struct aiff_chunk comm_hdr;
	struct aiff_commbase comm;
	struct aiff_chunk data_hdr;
	struct aiff_data data;
};

struct au_hdr {
	char id[4];
	be32_t offs;
	be32_t size;
#define AU_FMT_PCM8	2
#define AU_FMT_PCM16	3
#define AU_FMT_PCM24	4
#define AU_FMT_PCM32	5
#define AU_FMT_FLOAT	6
#define AU_FMT_ALAW	0x1b
#define AU_FMT_ULAW	1
	be32_t fmt;
	be32_t rate;
	be32_t nch;
	char desc[8];
	/* followed by optional desc[] continuation */
};

const char wav_id_riff[4] = {'R', 'I', 'F', 'F'};
const char wav_id_wave[4] = {'W', 'A', 'V', 'E'};
const char wav_id_data[4] = {'d', 'a', 't', 'a'};
const char wav_id_fmt[4] = {'f', 'm', 't', ' '};
const char wav_guid[14] = {
	0x00, 0x00, 0x00, 0x00,
	0x10, 0x00, 0x80, 0x00,
	0x00, 0xAA, 0x00, 0x38,
	0x9B, 0x71
};

const char aiff_id_form[4] = {'F', 'O', 'R', 'M'};
const char aiff_id_aiff[4] = {'A', 'I', 'F', 'F'};
const char aiff_id_aifc[4] = {'A', 'I', 'F', 'C'};
const char aiff_id_data[4] = {'S', 'S', 'N', 'D'};
const char aiff_id_comm[4] = {'C', 'O', 'M', 'M'};
const char aiff_id_none[4] = {'N', 'O', 'N', 'E'};
const char aiff_id_fl32[4] = {'f', 'l', '3', '2'};
const char aiff_id_ulaw[4] = {'u', 'l', 'a', 'w'};
const char aiff_id_alaw[4] = {'a', 'l', 'a', 'w'};

const char au_id[4] = {'.', 's', 'n', 'd'};

static inline unsigned int
le16_get(le16_t *p)
{
	return p->lw[0] | p->lw[1] << 8;
}

static inline void
le16_set(le16_t *p, unsigned int v)
{
	p->lw[0] = v;
	p->lw[1] = v >> 8;
}

static inline unsigned int
le32_get(le32_t *p)
{
	return p->ld[0] |
	       p->ld[1] << 8 |
	       p->ld[2] << 16 |
	       p->ld[3] << 24;
}

static inline void
le32_set(le32_t *p, unsigned int v)
{
	p->ld[0] = v;
	p->ld[1] = v >> 8;
	p->ld[2] = v >> 16;
	p->ld[3] = v >> 24;
}

static inline unsigned int
be16_get(be16_t *p)
{
	return p->bw[1] | p->bw[0] << 8;
}

static inline void
be16_set(be16_t *p, unsigned int v)
{
	p->bw[1] = v;
	p->bw[0] = v >> 8;
}

static inline unsigned int
be32_get(be32_t *p)
{
	return p->bd[3] |
	       p->bd[2] << 8 |
	       p->bd[1] << 16 |
	       p->bd[0] << 24;
}

static inline void
be32_set(be32_t *p, unsigned int v)
{
	p->bd[3] = v;
	p->bd[2] = v >> 8;
	p->bd[1] = v >> 16;
	p->bd[0] = v >> 24;
}

static int
afile_readhdr(struct afile *f, void *addr, size_t size)
{
	if (lseek(f->fd, 0, SEEK_SET) == -1) {
		log_puts(f->path);
		log_puts(": failed to seek to beginning of file\n");
		return 0;
	}
	if (read(f->fd, addr, size) != size) {
		log_puts(f->path);
		log_puts(": failed to read header\n");
		return 0;
	}
	return 1;
}

static int
afile_writehdr(struct afile *f, void *addr, size_t size)
{
	if (lseek(f->fd, 0, SEEK_SET) == -1) {
		log_puts(f->path);
		log_puts(": failed to seek back to header\n");
		return 0;
	}
	if (write(f->fd, addr, size) != size) {
		log_puts(f->path);
		log_puts(": failed to write header\n");
		return 0;
	}
	f->curpos = f->startpos;
	return 1;
}

static int
afile_checkpar(struct afile *f)
{
	if (f->nch == 0 || f->nch > NCHAN_MAX) {
		log_puts(f->path);
		log_puts(": ");
		log_putu(f->nch);
		log_puts(": unsupported number of channels\n");
		return 0;
	}
	if (f->rate < RATE_MIN || f->rate > RATE_MAX) {
		log_puts(f->path);
		log_puts(": ");
		log_putu(f->rate);
		log_puts(": unsupported rate\n");
		return 0;
	}
	if (f->par.bits < BITS_MIN || f->par.bits > BITS_MAX) {
		log_puts(f->path);
		log_puts(": ");
		log_putu(f->par.bits);
		log_puts(": unsupported bits per sample\n");
		return 0;
	}
	if (f->par.bits > f->par.bps * 8) {
		log_puts(f->path);
		log_puts(": bits larger than bytes-per-sample\n");
		return 0;
	}
	if (f->fmt == AFILE_FMT_FLOAT && f->par.bits != 32) {
		log_puts(f->path);
		log_puts(": only 32-bit floating points are supported\n");
		return 0;
	}
	return 1;
}

static int
afile_wav_readfmt(struct afile *f, unsigned int csize)
{
	struct wav_fmt fmt;
	unsigned int wenc;

	if (csize < WAV_FMT_SIZE) {
		log_puts(f->path);
		log_puts(": ");
		log_putu(csize);
		log_puts(": bogus format chunk size\n");
		return 0;
	}
	if (csize > WAV_FMT_EXT_SIZE)
		csize = WAV_FMT_EXT_SIZE;
	if (read(f->fd, &fmt, csize) != csize) {
		log_puts(f->path);
		log_puts(": failed to read format chunk\n");
		return 0;
	}
	wenc = le16_get(&fmt.fmt);
	f->par.bits = le16_get(&fmt.bits);
	if (wenc == WAV_FMT_EXT) {
		if (csize != WAV_FMT_EXT_SIZE) {
			log_puts(f->path);
			log_puts(": missing extended format chunk\n");
			return 0;
		}
		if (memcmp(fmt.guid, wav_guid, sizeof(wav_guid)) != 0) {
			log_puts(f->path);
			log_puts(": unknown format (GUID)\n");
			return 0;
		}
		f->par.bps = (f->par.bits + 7) / 8;
		f->par.bits = le16_get(&fmt.valbits);
		wenc = le16_get(&fmt.extfmt);
	} else
		f->par.bps = (f->par.bits + 7) / 8;
	f->nch = le16_get(&fmt.nch);
	f->rate = le32_get(&fmt.rate);
	f->par.le = 1;
	f->par.msb = 1;
	switch (wenc) {
	case WAV_FMT_PCM:
		f->fmt = AFILE_FMT_PCM;
		f->par.sig = (f->par.bits <= 8) ? 0 : 1;
		break;
	case WAV_FMT_ALAW:
		f->fmt = AFILE_FMT_ALAW;
		f->par.bits = 8;
		f->par.bps = 1;
		break;
	case WAV_FMT_ULAW:
		f->fmt = AFILE_FMT_ULAW;
		f->par.bits = 8;
		f->par.bps = 1;
		break;
	case WAV_FMT_FLOAT:
		f->fmt = AFILE_FMT_FLOAT;
		break;
	default:
		log_putu(wenc);
		log_puts(": unsupported encoding\n");
		return 0;
	}
	return afile_checkpar(f);
}

static int
afile_wav_readhdr(struct afile *f)
{
	struct wav_riff riff;
	struct wav_chunk chunk;
	unsigned int csize, rsize, pos = 0;
	int fmt_done = 0;

	if (!afile_readhdr(f, &riff, sizeof(struct wav_riff)))
		return 0;
	if (memcmp(&riff.id, &wav_id_riff, 4) != 0 ||
	    memcmp(&riff.type, &wav_id_wave, 4)) {
		log_puts(f->path);
		log_puts(": not a .wav file\n");
		return 0;
	}
	rsize = le32_get(&riff.size);
	for (;;) {
		if (pos + sizeof(struct wav_chunk) > rsize) {
			log_puts(f->path);
			log_puts(": missing data chunk\n");
			return 0;
		}
		if (read(f->fd, &chunk, sizeof(chunk)) != sizeof(chunk)) {
			log_puts(f->path);
			log_puts(": failed to read chunk header\n");
			return 0;
		}
		csize = le32_get(&chunk.size);
		if (memcmp(chunk.id, wav_id_fmt, 4) == 0) {
			if (!afile_wav_readfmt(f, csize))
				return 0;
			fmt_done = 1;
		} else if (memcmp(chunk.id, wav_id_data, 4) == 0) {
			f->startpos = pos + sizeof(riff) + sizeof(chunk);
			f->endpos = f->startpos + csize;
			break;
		} else {
#ifdef DEBUG
			if (log_level >= 2) {
				log_puts(f->path);
				log_puts(": skipped unknown chunk\n");
			}
#endif
		}

		/*
		 * next chunk
		 */
		pos += sizeof(struct wav_chunk) + csize;
		if (lseek(f->fd, sizeof(riff) + pos, SEEK_SET) == -1) {
			log_puts(f->path);
			log_puts(": filed to seek to chunk\n");
			return 0;
		}
	}
	if (!fmt_done) {
		log_puts(f->path);
		log_puts(": missing format chunk\n");
		return 0;
	}
	return 1;
}

/*
 * Write header and seek to start position
 */
static int
afile_wav_writehdr(struct afile *f)
{
	struct wav_hdr hdr;

	memset(&hdr, 0, sizeof(struct wav_hdr));
	memcpy(hdr.riff.id, wav_id_riff, 4);
	memcpy(hdr.riff.type, wav_id_wave, 4);
	le32_set(&hdr.riff.size, f->endpos - sizeof(hdr.riff));
	memcpy(hdr.fmt_hdr.id, wav_id_fmt, 4);
	le32_set(&hdr.fmt_hdr.size, sizeof(hdr.fmt));
	le16_set(&hdr.fmt.fmt, 1);
	le16_set(&hdr.fmt.nch, f->nch);
	le32_set(&hdr.fmt.rate, f->rate);
	le32_set(&hdr.fmt.byterate, f->rate * f->par.bps * f->nch);
	le16_set(&hdr.fmt.blkalign, f->par.bps * f->nch);
	le16_set(&hdr.fmt.bits, f->par.bits);
	memcpy(hdr.data_hdr.id, wav_id_data, 4);
	le32_set(&hdr.data_hdr.size, f->endpos - f->startpos);
	return afile_writehdr(f, &hdr, sizeof(struct wav_hdr));
}

static int
afile_aiff_readcomm(struct afile *f, unsigned int csize,
    int comp, unsigned int *nfr)
{
	struct aiff_comm comm;
	unsigned int csize_min;
	unsigned int e, m;

	csize_min = comp ?
	    sizeof(struct aiff_comm) : sizeof(struct aiff_commbase);
	if (csize < csize_min) {
		log_puts(f->path);
		log_puts(": ");
		log_putu(csize);
		log_puts(": bogus comm chunk size\n");
		return 0;
	}
	if (read(f->fd, &comm, csize_min) != csize_min) {
		log_puts(f->path);
		log_puts(": failed to read comm chunk\n");
		return 0;
	}
	f->nch = be16_get(&comm.base.nch);
	e = be16_get(&comm.base.rate_ex);
	m = be32_get(&comm.base.rate_hi);
	if (e < 0x3fff || e > 0x3fff + 31) {
		log_puts(f->path);
		log_puts(": malformed sample rate\n");
		return 0;
	}
	f->rate = m >> (0x3fff + 31 - e);
	if (comp) {
		if (memcmp(comm.comp_id, aiff_id_none, 4) == 0) {
			f->fmt = AFILE_FMT_PCM;
			f->par.bits = be16_get(&comm.base.bits);
		} else if (memcmp(comm.comp_id, aiff_id_fl32, 4) == 0) {
			f->fmt = AFILE_FMT_FLOAT;
			f->par.bits = 32;
		} else if (memcmp(comm.comp_id, aiff_id_ulaw, 4) == 0) {
			f->fmt = AFILE_FMT_ULAW;
			f->par.bits = 8;
		} else if (memcmp(comm.comp_id, aiff_id_alaw, 4) == 0) {
			f->fmt = AFILE_FMT_ALAW;
			f->par.bits = 8;
		} else {
			log_puts(f->path);
			log_puts(": unsupported encoding\n");
			return 0;
		}
	} else {
		f->fmt = AFILE_FMT_PCM;
		f->par.bits = be16_get(&comm.base.bits);
	}
	f->par.le = 0;
	f->par.sig = 1;
	f->par.msb = 1;
	f->par.bps = (f->par.bits + 7) / 8;
	*nfr = be32_get(&comm.base.nfr);
	return afile_checkpar(f);
}

static int
afile_aiff_readdata(struct afile *f, unsigned int csize, unsigned int *roffs)
{
	struct aiff_data data;

	if (csize < sizeof(struct aiff_data)) {
		log_puts(f->path);
		log_puts(": ");
		log_putu(csize);
		log_puts(": bogus data chunk size\n");
		return 0;
	}
	csize = sizeof(struct aiff_data);
	if (read(f->fd, &data, csize) != csize) {
		log_puts(f->path);
		log_puts(": failed to read data chunk\n");
		return 0;
	}
	*roffs = csize + be32_get(&data.offs);
	return 1;
}

static int
afile_aiff_readhdr(struct afile *f)
{
	struct aiff_form form;
	struct aiff_chunk chunk;
	unsigned int csize, rsize, nfr = 0, pos = 0, offs;
	int comm_done = 0, comp;

	if (!afile_readhdr(f, &form, sizeof(struct aiff_form)))
		return 0;
	if (memcmp(&form.id, &aiff_id_form, 4) != 0) {
		log_puts(f->path);
		log_puts(": not an aiff file\n");
		return 0;
	}
	if (memcmp(&form.type, &aiff_id_aiff, 4) == 0) {
		comp = 0;
	} else if (memcmp(&form.type, &aiff_id_aifc, 4) == 0)
		comp = 1;
	else {
		log_puts(f->path);
		log_puts(": unsupported aiff file sub-type\n");
		return 0;
	}
	rsize = be32_get(&form.size);
	for (;;) {
		if (pos + sizeof(struct aiff_chunk) > rsize) {
			log_puts(f->path);
			log_puts(": missing data chunk\n");
			return 0;
		}
		if (read(f->fd, &chunk, sizeof(chunk)) != sizeof(chunk)) {
			log_puts(f->path);
			log_puts(": failed to read chunk header\n");
			return 0;
		}
		csize = be32_get(&chunk.size);
		if (memcmp(chunk.id, aiff_id_comm, 4) == 0) {
			if (!afile_aiff_readcomm(f, csize, comp, &nfr))
				return 0;
			comm_done = 1;
		} else if (memcmp(chunk.id, aiff_id_data, 4) == 0) {
			if (!afile_aiff_readdata(f, csize, &offs))
				return 0;
			f->startpos = sizeof(form) + pos +
			    sizeof(chunk) + offs;
			break;
		} else {
#ifdef DEBUG
			if (log_level >= 2) {
				log_puts(f->path);
				log_puts(": skipped unknown chunk\n");
			}
#endif
		}

		/*
		 * The aiff spec says "Each Chunk must contain an even
		 * number of bytes. For those Chunks whose total
		 * contents would yield an odd number of bytes, a zero
		 * pad byte must be added at the end of the Chunk. This
		 * pad byte is not included in ckDataSize, which
		 * indicates the size of the data in the Chunk."
		 */
		csize = (csize + 1) & ~1;
		pos += sizeof(struct aiff_chunk) + csize;

		if (lseek(f->fd, sizeof(form) + pos, SEEK_SET) == -1) {
			log_puts(f->path);
			log_puts(": filed to seek to chunk\n");
			return 0;
		}
	}
	if (!comm_done) {
		log_puts(f->path);
		log_puts(": missing comm chunk\n");
		return 0;
	}
	f->endpos = f->startpos + f->par.bps * f->nch * nfr;
	return 1;
}

/*
 * Write header and seek to start position
 */
static int
afile_aiff_writehdr(struct afile *f)
{
	struct aiff_hdr hdr;
	unsigned int bpf;
	unsigned int e, m;

	/* convert rate to 80-bit float (exponent and fraction part) */
	m = f->rate;
	e = 0x3fff + 31;
	while ((m & 0x80000000) == 0) {
		e--;
		m <<= 1;
	}

	/* bytes per frame */
	bpf = f->nch * f->par.bps;

	memset(&hdr, 0, sizeof(struct aiff_hdr));
	memcpy(hdr.form.id, aiff_id_form, 4);
	memcpy(hdr.form.type, aiff_id_aiff, 4);
	be32_set(&hdr.form.size, f->endpos - sizeof(hdr.form));

	memcpy(hdr.comm_hdr.id, aiff_id_comm, 4);
	be32_set(&hdr.comm_hdr.size, sizeof(hdr.comm));
	be16_set(&hdr.comm.nch, f->nch);
	be16_set(&hdr.comm.bits, f->par.bits);
	be16_set(&hdr.comm.rate_ex, e);
	be32_set(&hdr.comm.rate_hi, m);
	be32_set(&hdr.comm.rate_lo, 0);
	be32_set(&hdr.comm.nfr, (f->endpos - f->startpos) / bpf);

	memcpy(hdr.data_hdr.id, aiff_id_data, 4);
	be32_set(&hdr.data_hdr.size, f->endpos - f->startpos);
	be32_set(&hdr.data.offs, 0);
	be32_set(&hdr.data.blksz, 0);
	return afile_writehdr(f, &hdr, sizeof(struct aiff_hdr));
}

static int
afile_au_readhdr(struct afile *f)
{
	struct au_hdr hdr;
	unsigned int fmt;

	if (!afile_readhdr(f, &hdr, sizeof(struct au_hdr)))
		return 0;
	if (memcmp(&hdr.id, &au_id, 4) != 0) {
		log_puts(f->path);
		log_puts(": not a .au file\n");
		return 0;
	}
	f->startpos = be32_get(&hdr.offs);
	f->endpos = f->startpos + be32_get(&hdr.size);
	fmt = be32_get(&hdr.fmt);
	switch (fmt) {
	case AU_FMT_PCM8:
		f->fmt = AFILE_FMT_PCM;
		f->par.bits = 8;
		break;
	case AU_FMT_PCM16:
		f->fmt = AFILE_FMT_PCM;
		f->par.bits = 16;
		break;
	case AU_FMT_PCM24:
		f->fmt = AFILE_FMT_PCM;
		f->par.bits = 24;
		break;
	case AU_FMT_PCM32:
		f->fmt = AFILE_FMT_PCM;
		f->par.bits = 32;
		break;
	case AU_FMT_ULAW:
		f->fmt = AFILE_FMT_ULAW;
		f->par.bits = 8;
		break;
	case AU_FMT_ALAW:
		f->fmt = AFILE_FMT_ALAW;
		f->par.bits = 8;
		break;
	case AU_FMT_FLOAT:
		f->fmt = AFILE_FMT_FLOAT;
		f->par.bits = 32;
		break;
	default:
		log_puts(f->path);
		log_puts(": ");
		log_putu(fmt);
		log_puts(": unsupported encoding\n");
		return 0;
	}
	f->par.le = 0;
	f->par.sig = 1;
	f->par.bps = f->par.bits / 8;
	f->par.msb = 0;
	f->rate = be32_get(&hdr.rate);
	f->nch = be32_get(&hdr.nch);
	if (lseek(f->fd, f->startpos, SEEK_SET) == -1) {
		log_puts(f->path);
		log_puts(": ");
		log_puts("failed to seek to data chunk\n");
		return 0;
	}
	return afile_checkpar(f);
}

/*
 * Write header and seek to start position
 */
static int
afile_au_writehdr(struct afile *f)
{
	struct au_hdr hdr;
	unsigned int fmt;

	memset(&hdr, 0, sizeof(struct au_hdr));
	memcpy(hdr.id, au_id, 4);
	be32_set(&hdr.offs, f->startpos);
	be32_set(&hdr.size, f->endpos - f->startpos);
	switch (f->par.bits) {
	case 8:
		fmt = AU_FMT_PCM8;
		break;
	case 16:
		fmt = AU_FMT_PCM16;
		break;
	case 24:
		fmt = AU_FMT_PCM24;
		break;
	case 32:
		fmt = AU_FMT_PCM32;
		break;
#ifdef DEBUG
	default:
		log_puts(f->path);
		log_puts(": wrong precision\n");
		panic();
		return 0;
#endif
	}
	be32_set(&hdr.fmt, fmt);
	be32_set(&hdr.rate, f->rate);
	be32_set(&hdr.nch, f->nch);
	return afile_writehdr(f, &hdr, sizeof(struct au_hdr));
}

size_t
afile_read(struct afile *f, void *data, size_t count)
{
	off_t maxread;
	ssize_t n;

	if (f->endpos >= 0) {
		maxread = f->endpos - f->curpos;
		if (maxread == 0) {
#ifdef DEBUG
			if (log_level >= 3) {
				log_puts(f->path);
				log_puts(": end reached\n");
			}
#endif
			return 0;
		}
		if (count > maxread)
			count = maxread;
	}
	n = read(f->fd, data, count);
	if (n == -1) {
		log_puts(f->path);
		log_puts(": couldn't read\n");
		return 0;
	}
	f->curpos += n;
	return n;
}

size_t
afile_write(struct afile *f, void *data, size_t count)
{
	off_t maxwrite;
	int n;

	if (f->maxpos >= 0) {
		maxwrite = f->maxpos - f->curpos;
		if (maxwrite == 0) {
#ifdef DEBUG
			if (log_level >= 3) {
				log_puts(f->path);
				log_puts(": max file size reached\n");
			}
#endif
			return 0;
		}
		if (count > maxwrite)
			count = maxwrite;
	}
	n = write(f->fd, data, count);
	if (n == -1) {
		log_puts(f->path);
		log_puts(": couldn't write\n");
		return 0;
	}
	f->curpos += n;
	if (f->endpos < f->curpos)
		f->endpos = f->curpos;
	return n;
}

int
afile_seek(struct afile *f, off_t pos)
{
	pos += f->startpos;
	if (f->endpos >= 0 && pos > f->endpos && !f->par.sig) {
		log_puts(f->path);
		log_puts(": attempt to seek outside file boundaries\n");
		return 0;
	}

	/*
	 * seek only if needed to avoid errors with pipes & sockets
	 */
	if (pos != f->curpos) {
		if (lseek(f->fd, pos, SEEK_SET) == -1) {
			log_puts(f->path);
			log_puts(": couldn't seek\n");
			return 0;
		}
		f->curpos = pos;
	}
	return 1;
}

void
afile_close(struct afile *f)
{
	if (f->flags & AFILE_FWRITE) {
		if (f->hdr == AFILE_HDR_WAV)
			afile_wav_writehdr(f);
		else if (f->hdr == AFILE_HDR_AIFF)
			afile_aiff_writehdr(f);
		else if (f->hdr == AFILE_HDR_AU)
			afile_au_writehdr(f);
	}
	close(f->fd);
}

int
afile_open(struct afile *f, char *path, int hdr, int flags,
    struct aparams *par, int rate, int nch)
{
	char *ext;
	static union {
		struct wav_hdr wav;
		struct aiff_hdr aiff;
		struct au_hdr au;
	} dummy;

	f->par = *par;
	f->rate = rate;
	f->nch = nch;
	f->flags = flags;
	f->hdr = hdr;
	if (hdr == AFILE_HDR_AUTO) {
		f->hdr = AFILE_HDR_RAW;
		ext = strrchr(path, '.');
		if (ext != NULL) {
			ext++;
			if (strcasecmp(ext, "aif") == 0 ||
			    strcasecmp(ext, "aiff") == 0 ||
			    strcasecmp(ext, "aifc") == 0)
				f->hdr = AFILE_HDR_AIFF;
			else if (strcasecmp(ext, "au") == 0 ||
			    strcasecmp(ext, "snd") == 0)
				f->hdr = AFILE_HDR_AU;
			else if (strcasecmp(ext, "wav") == 0)
				f->hdr = AFILE_HDR_WAV;
		}
	}
	if (f->flags == AFILE_FREAD) {
		if (strcmp(path, "-") == 0) {
			f->path = "stdin";
			f->fd = STDIN_FILENO;
		} else {
			f->path = path;
			f->fd = open(f->path, O_RDONLY);
			if (f->fd == -1) {
				log_puts(f->path);
				log_puts(": failed to open for reading\n");
				return 0;
			}
		}
		if (f->hdr == AFILE_HDR_WAV) {
			if (!afile_wav_readhdr(f))
				goto bad_close;
		} else if (f->hdr == AFILE_HDR_AIFF) {
			if (!afile_aiff_readhdr(f))
				goto bad_close;
		} else if (f->hdr == AFILE_HDR_AU) {
			if (!afile_au_readhdr(f))
				goto bad_close;
		} else {
			f->startpos = 0;
			f->endpos = -1; /* read until EOF */
			f->fmt = AFILE_FMT_PCM;
		}
		f->curpos = f->startpos;
	} else if (flags == AFILE_FWRITE) {
		if (strcmp(path, "-") == 0) {
			f->path = "stdout";
			f->fd = STDOUT_FILENO;
		} else {
			f->path = path;
			f->fd = open(f->path,
			    O_WRONLY | O_TRUNC | O_CREAT, 0666);
			if (f->fd == -1) {
				log_puts(f->path);
				log_puts(": failed to create file\n");
				return 0;
			}
		}
		if (f->hdr == AFILE_HDR_WAV) {
			f->par.bps = (f->par.bits + 7) >> 3;
			if (f->par.bits > 8) {
				f->par.le = 1;
				f->par.sig = 1;
			} else
				f->par.sig = 0;
			if (f->par.bits & 7)
				f->par.msb = 1;
			f->endpos = f->startpos = sizeof(struct wav_hdr);
			f->maxpos = 0x7fffffff;
			if (!afile_writehdr(f, &dummy, sizeof(struct wav_hdr)))
				goto bad_close;
		} else if (f->hdr == AFILE_HDR_AIFF) {
			f->par.bps = (f->par.bits + 7) >> 3;
			if (f->par.bps > 1)
				f->par.le = 0;
			f->par.sig = 1;
			if (f->par.bits & 7)
				f->par.msb = 1;
			f->endpos = f->startpos = sizeof(struct aiff_hdr);
			f->maxpos = 0x7fffffff;
			if (!afile_writehdr(f, &dummy,
				sizeof(struct aiff_hdr)))
				goto bad_close;
		} else if (f->hdr == AFILE_HDR_AU) {
			f->par.bits = (f->par.bits + 7) & ~7;
			f->par.bps = f->par.bits / 8;
			f->par.le = 0;
			f->par.sig = 1;
			f->par.msb = 1;
			f->endpos = f->startpos = sizeof(struct au_hdr);
			f->maxpos = 0x7fffffff;
			if (!afile_writehdr(f, &dummy, sizeof(struct au_hdr)))
				goto bad_close;
		} else {
			f->endpos = f->startpos = 0;
			f->maxpos = -1;
		}
		f->curpos = f->startpos;
	} else {
#ifdef DEBUG
		log_puts("afile_open: wrong flags\n");
		panic();
#endif
	}
	return 1;
bad_close:
	close(f->fd);
	return 0;
}