toast.c

柏林科技大学开发的gsm编码程序

/*
 * Copyright 1992 by Jutta Degener and Carsten Bormann, Technische
 * Universitaet Berlin.  See the accompanying file "COPYRIGHT" for
 * details.  THERE IS ABSOLUTELY NO WARRANTY FOR THIS SOFTWARE.
 */

/* $Header: /home/kbs/jutta/src/gsm/gsm-1.0/src/RCS/toast.c,v 1.4 1994/05/10 20:18:49 jutta Exp $ */

#include	"private.h"
#include	"toast.h"


/*  toast -- lossy sound compression using the gsm library.
 */

char   * progname;

int	f_decode   = 0;		/* decode rather than encode	 (-d) */
int 	f_cat	   = 0;		/* write to stdout, not foo.gsm	 (-c) */
int	f_force	   = 0;		/* force deletion 		 (-f) */
int	f_precious = 0;		/* avoid deletion		 (-p) */
int	f_fast	   = 0;		/* use faster fpt algorithm	 (-F) */
int	f_verbose  = 0;		/* debugging			 (-V) */

struct stat instat;		/* stat (inname) 		 */

FILE	*in, 	 *out;
char	*inname, *outname;

/*
 *  The function (*output)() writes a frame of 160 samples given as
 *  160 signed 16 bit values (gsm_signals) to <out>.
 *  The function (*input)() reads one such frame from <in>.
 *  The function (*init_output)() begins output (e.g. writes a header).,
 *  The function (*init_input)() begins input (e.g. skips a header).
 *
 *  There are different versions of input, output, init_input and init_output
 *  for different formats understood by toast; which ones are used 
 *  depends on the command line arguments and, in their absence, the
 *  filename; the fallback is #defined in toast.h
 *
 *  The specific implementations of input, output, init_input and init_output
 *  for a format `foo' live in toast_foo.c.
 */

int	(*output   ) P((gsm_signal *)),
	(*input    ) P((gsm_signal *));
int	(*init_input)  P((void)),
	(*init_output) P((void));

static int	generic_init P0() { return 0; }	/* NOP */

struct fmtdesc {

	char * name, * longname, * suffix;

	int  (* init_input )  P((void)),
	     (* init_output)  P((void));

	int  (* input ) P((gsm_signal * )),
	     (* output) P((gsm_signal * ));

} f_audio = {
		"audio",
		"8 kHz, 8 bit u-law encoding with Sun audio header", ".au",
		audio_init_input,
		audio_init_output,
		ulaw_input,
		ulaw_output
}, f_ulaw = {
		"u-law", "plain 8 kHz, 8 bit u-law encoding", ".u",
		generic_init,
		generic_init,
		ulaw_input,
		ulaw_output 

}, f_alaw = {
		"A-law", "8 kHz, 8 bit A-law encoding", ".A",
		generic_init,
		generic_init,
		alaw_input,
		alaw_output

}, f_linear = {
		"linear",
		"16 bit (13 significant) signed 8 kHz signal", ".l",
		generic_init,
		generic_init,
		linear_input,
		linear_output
};

struct fmtdesc * alldescs[] = {
	&f_audio,
	&f_alaw,
	&f_ulaw,
	&f_linear,
	(struct fmtdesc *)NULL
};

#define	DEFAULT_FORMAT	f_ulaw		/* default audio format, others	*/
					/* are: f_alaw,f_audio,f_linear */
struct fmtdesc * f_format  = 0;

/*
 *  basename + suffix of a pathname
 */
static char * endname P1((name), char * name)
{
	if (name) {
		char * s = strrchr(name, '/');
		if (s && s[1]) name = s + 1;
	}
	return name;

}

/*
 *  Try to figure out what we're supposed to do from the argv[0], if
 *  any, and set the parameters accordingly.
 */
static void parse_argv0 P1((av0), char * av0 )
{
	int 	l;

	progname = av0 = endname(av0 ? av0 : "toast");

	/*  If the name starts with `un', we want to decode, not code.
	 *  If the name ends in `cat', we want to write to stdout,
	 *  and decode as well.
	 */

	if (!strncmp(av0, "un", 2)) f_decode = 1;
	if (  (l = strlen(av0)) >= 3 /* strlen("cat") */
	   && !strcmp( av0 + l - 3, "cat" )) f_cat = f_decode = 1;
}


/*
 *  Check whether the name (possibly generated by appending
 *  .gsm to something else) is short enough for this system.
 */
static int length_okay P1((name), char * name)
{
	long	max_filename_length = 0;
	char	* end;

	/* If our _pathname_ is too long, we'll usually not be
	 * able to open the file at all -- don't worry about that.
	 * 
	 * But if the _filename_ is too long, there is danger of
	 * silent truncation on some systems, which results
	 * in the target replacing the source!
	 */

	if (!name) return 0;
	end = endname(name);

#ifdef	NAME_MAX
	max_filename_length  = NAME_MAX;
#else
#ifdef	_PC_NAME_MAX
#ifdef USE_PATHCONF
	{	char * s, tmp; 
		
		/*  s = dirname(name)
		 */
		if ((s = end) > name) {
			if (s > name + 1) s--;
			tmp = s;
			*s  = 0;
		}

		errno = 0;
		max_filename_length = pathconf(s > name ? name : ".",
			_PC_NAME_MAX);
		if (max_filename_length == -1 && errno) {
			perror( s > name ? name : "." );
			fprintf(stderr,
		"%s: cannot get dynamic filename length limit for %s.\n",
				progname, s > name ? name : ".");
			return 0;
		}
		if (s > name) *s = tmp;
	}
#endif /* USE_PATHCONF  */
#endif /* _PC_NAME_MAX  */
#endif /* !NAME_MAX 	*/

	if (max_filename_length > 0 && strlen(end) > max_filename_length) {
		fprintf(stderr,
			"%s: filename \"%s\" is too long (maximum is %ld)\n",
			progname, endname(name), max_filename_length );
		return 0;
	}

	return 1;
}

/*
 *  Return a pointer the suffix of a string, if any.
 *  A suffix alone has no suffix, an empty suffix can not be had.
 */
static char * suffix P2((name, suf), char *name, char * suf) 
{
	size_t nlen = strlen(name);
	size_t slen = strlen(suf);

	if (!slen || nlen <= slen) return (char *)0;
	name += nlen - slen;
	return memcmp(name, suf, slen) ? (char *)0 : name;
}


static void catch_signals P1((fun), SIGHANDLER_T (*fun) ()) 
{
#ifdef	SIGHUP
	signal( SIGHUP,   fun );
#endif
#ifdef	SIGINT
	signal( SIGINT,   fun );
#endif
#ifdef	SIGPIPE
	signal( SIGPIPE,  fun );
#endif
#ifdef	SIGTERM
	signal( SIGTERM,  fun );
#endif
#ifdef	SIGXFSZ
	signal( SIGXFSZ,  fun );
#endif
}

static SIGHANDLER_T onintr P0()
{
	char * tmp = outname;

#ifdef	HAS_SYSV_SIGNALS
	catch_signals( SIG_IGN );
#endif

	outname = (char *)0;
	if (tmp) (void)unlink(tmp);

	exit(1);
}

/*
 *  Allocate some memory and complain if it fails.
 */
static char * emalloc P1((len), size_t len)
{
	char * s;
	if (!(s = malloc(len))) {
		fprintf(stderr, "%s: failed to malloc %d bytes -- abort\n",
			progname, len);
		onintr();
		exit(1);
	}
	return s;
}

static char* normalname P3((name, want, cut), char *name, char *want,char *cut)
{
	size_t	maxlen;
	char 	* s, * p;

	p = (char *)0;
	if (!name) return p;

	maxlen = strlen(name) + 1 + strlen(want) + strlen(cut);
	p = strcpy(emalloc(maxlen), name);

	if (s = suffix(p, cut)) strcpy(s, want);
	else if (*want && !suffix(p, want)) strcat(p, want);

	return p;
}

/*
 *  Generate a `plain' (non-encoded) name from a given name.
 */
static char * plainname P1((name), char *name)
{
	return normalname(name, "", SUFFIX_TOASTED );
}

/*
 *  Generate a `code' name (foo.Z) from a given name.
 */
static char * codename P1((name), char *name)
{
	return normalname( name, SUFFIX_TOASTED, "" );
}

/*
 *  If we're supposed to ask (fileno (stderr) is a tty, and f_force not
 *  set), ask the user whether to overwrite a file or not.
 */
static int ok_to_replace P1(( name ), char * name)
{
	int reply, c;

	if (f_force) return 1;			/* YES, do replace   */
	if (!isatty(fileno(stderr))) return 0;	/* NO, don't replace */

	fprintf(stderr,
		"%s already exists; do you wish to overwrite %s (y or n)? ",
		name, name);
	fflush(stderr);

	for (c = reply = getchar(); c != '\n' && c != EOF; c = getchar()) ;
	if (reply == 'y') return 1;

	fprintf(stderr, "\tnot overwritten\n");
	return 0;
}

static void update_mode P0()
{
	if (!instat.st_nlink) return;		/* couldn't stat in */

#ifdef HAS_FCHMOD
	if (fchmod(fileno(out), instat.st_mode & 07777)) {
		perror(outname);
		fprintf(stderr, "%s: could not change file mode of \"%s\"\n",
			progname, outname);
	}
#else 
	if (outname && chmod(outname, instat.st_mode & 07777)) {
		perror(outname);
		fprintf(stderr, "%s: could not change file mode of \"%s\"\n",
			progname, outname);
	}
#endif /* HAS_FCHMOD */
}

static void update_own P0()
{
	if (!instat.st_nlink) return; /* couldn't stat in */
#ifdef HAS_FCHOWN
	(void)fchown(fileno(out), instat.st_uid, instat.st_gid);
#else 
/*	(void)chown(outname, instat.st_uid, instat.st_gid);*/
#endif /* HAS_FCHOWN */
}

static void update_times P0()
{
	if (!instat.st_nlink) return; 	/* couldn't stat in */

#ifdef HAS_UTIMES
	if (outname) {
		struct timeval tv[2];

		tv[0].tv_sec  = instat.st_atime;
		tv[1].tv_sec  = instat.st_mtime;
		tv[0].tv_usec = tv[1].tv_usec = 0;
		(void) utimes(outname, tv);
	}
#else
#ifdef HAS_UTIME

	if (outname) {

#ifdef	HAS_UTIMBUF
		struct utimbuf ut;

		ut.actime     = instat.st_atime;
		ut.modtime    = instat.st_mtime;

#	ifdef	HAS_UTIMEUSEC
		ut.acusec     = instat.st_ausec;
		ut.modusec    = instat.st_musec;
#	endif 	/* HAS_UTIMEUSEC */

		(void) utime(outname, &ut);

#else /* UTIMBUF */

		time_t ut[2];

		ut[0] = instat.st_atime;