Head

GCC Code Coverage Report

Directory:	./		Exec	Total	Coverage
File:	bin/chio/parse.y	Lines:	0	179	0.0 %
Date:	2017-11-13	Branches:	0	159	0.0 %


/*	$OpenBSD: parse.y,v 1.20 2014/11/20 05:51:20 jsg Exp $ */

/*
 * Copyright (c) 2006 Bob Beck <beck@openbsd.org>
 * Copyright (c) 2002-2006 Henning Brauer <henning@openbsd.org>
 * Copyright (c) 2001 Markus Friedl.  All rights reserved.
 * Copyright (c) 2001 Daniel Hartmeier.  All rights reserved.
 * Copyright (c) 2001 Theo de Raadt.  All rights reserved.
 *
 * 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 <sys/types.h>
#include <sys/socket.h>
#include <sys/queue.h>

#include <ctype.h>
#include <err.h>
#include <libgen.h>
#include <limits.h>
#include <stdarg.h>
#include <stdio.h>
#include <string.h>

TAILQ_HEAD(files, file)		 files = TAILQ_HEAD_INITIALIZER(files);
static struct file {
	TAILQ_ENTRY(file)	 entry;
	FILE			*stream;
	char			*name;
	int			 lineno;
	int			 errors;
} *file, *topfile;
struct file	*pushfile(const char *);
int		 popfile(void);
int		 yyparse(void);
int		 yylex(void);
int		 yyerror(const char *, ...)
    __attribute__((__format__ (printf, 1, 2)))
    __attribute__((__nonnull__ (1)));
int		 kw_cmp(const void *, const void *);
int		 lookup(char *);
int		 lgetc(int);
int		 lungetc(int);
int		 findeol(void);
char		*parse_tapedev(const char *, const char *, int);
struct changer	*new_changer(char *);

struct changer {
	TAILQ_ENTRY(changer)	  entry;
	char			 *name;
	char			**drives;
	u_int			  drivecnt;
};
TAILQ_HEAD(changers, changer)	 changers;
struct changer			*curchanger;

typedef struct {
	union {
		int64_t			 number;
		char			*string;
	} v;
	int lineno;
} YYSTYPE;

%}

%token	CHANGER
%token	DRIVE
%token	ERROR
%token	<v.string>		STRING
%token	<v.number>		NUMBER
%%

grammar		: /* empty */
		| grammar '\n'
		| grammar main '\n'
		| grammar error '\n'		{ file->errors++; }
		;

optnl		: '\n' optnl
		|
		;

nl		: '\n' optnl
		;

main		: CHANGER STRING optnl '{' optnl {
			curchanger = new_changer($2);
		}
		    changeropts_l '}' {
			TAILQ_INSERT_TAIL(&changers, curchanger, entry);
			curchanger = NULL;
		}
		;

changeropts_l	: changeropts_l changeroptsl
		| changeroptsl
		;

changeroptsl	: changeropts nl
		| error nl
		;

changeropts	: DRIVE STRING	{
			void *newp;

			if ((newp = reallocarray(curchanger->drives,
			    curchanger->drivecnt + 1,
			    sizeof(curchanger->drives))) == NULL)
				err(1, NULL);
			curchanger->drives = newp;
			if ((curchanger->drives[curchanger->drivecnt] =
			    strdup($2)) == NULL)
				err(1, NULL);
			curchanger->drivecnt++;
			free($2);
		}
		;

%%

struct keywords {
	const char	*k_name;
	int		 k_val;
};

int
yyerror(const char *fmt, ...)
{
	va_list		 ap;
	char		*msg;

	file->errors++;
	va_start(ap, fmt);
	if (vasprintf(&msg, fmt, ap) == -1)
		err(1, "yyerror vasprintf");
	va_end(ap);
	err(1, "%s:%d: %s", file->name, yylval.lineno, msg);
	free(msg);
	return (0);
}

int
kw_cmp(const void *k, const void *e)
{
	return (strcmp(k, ((const struct keywords *)e)->k_name));
}

int
lookup(char *s)
{
	/* this has to be sorted always */
	static const struct keywords keywords[] = {
		{ "changer",		CHANGER},
		{ "drive",		DRIVE}
	};
	const struct keywords	*p;

	p = bsearch(s, keywords, sizeof(keywords)/sizeof(keywords[0]),
	    sizeof(keywords[0]), kw_cmp);

	if (p)
		return (p->k_val);
	else
		return (STRING);
}

#define MAXPUSHBACK	128

u_char	*parsebuf;
int	 parseindex;
u_char	 pushback_buffer[MAXPUSHBACK];
int	 pushback_index = 0;

int
lgetc(int quotec)
{
	int		c, next;

	if (parsebuf) {
		/* Read character from the parsebuffer instead of input. */
		if (parseindex >= 0) {
			c = parsebuf[parseindex++];
			if (c != '\0')
				return (c);
			parsebuf = NULL;
		} else
			parseindex++;
	}

	if (pushback_index)
		return (pushback_buffer[--pushback_index]);

	if (quotec) {
		if ((c = getc(file->stream)) == EOF) {
			yyerror("reached end of file while parsing "
			    "quoted string");
			if (file == topfile || popfile() == EOF)
				return (EOF);
			return (quotec);
		}
		return (c);
	}

	while ((c = getc(file->stream)) == '\\') {
		next = getc(file->stream);
		if (next != '\n') {
			c = next;
			break;
		}
		yylval.lineno = file->lineno;
		file->lineno++;
	}

	while (c == EOF) {
		if (file == topfile || popfile() == EOF)
			return (EOF);
		c = getc(file->stream);
	}
	return (c);
}

int
lungetc(int c)
{
	if (c == EOF)
		return (EOF);
	if (parsebuf) {
		parseindex--;
		if (parseindex >= 0)
			return (c);
	}
	if (pushback_index < MAXPUSHBACK-1)
		return (pushback_buffer[pushback_index++] = c);
	else
		return (EOF);
}

int
findeol(void)
{
	int	c;

	parsebuf = NULL;
	pushback_index = 0;

	/* skip to either EOF or the first real EOL */
	while (1) {
		c = lgetc(0);
		if (c == '\n') {
			file->lineno++;
			break;
		}
		if (c == EOF)
			break;
	}
	return (ERROR);
}

int
yylex(void)
{
	u_char	 buf[8096];
	u_char	*p;
	int	 quotec, next, c;
	int	 token;

	p = buf;
	while ((c = lgetc(0)) == ' ' || c == '\t')
		; /* nothing */

	yylval.lineno = file->lineno;
	if (c == '#')
		while ((c = lgetc(0)) != '\n' && c != EOF)
			; /* nothing */

	switch (c) {
	case '\'':
	case '"':
		quotec = c;
		while (1) {
			if ((c = lgetc(quotec)) == EOF)
				return (0);
			if (c == '\n') {
				file->lineno++;
				continue;
			} else if (c == '\\') {
				if ((next = lgetc(quotec)) == EOF)
					return (0);
				if (next == quotec || c == ' ' || c == '\t')
					c = next;
				else if (next == '\n')
					continue;
				else
					lungetc(next);
			} else if (c == quotec) {
				*p = '\0';
				break;
			} else if (c == '\0') {
				yyerror("syntax error");
				return (findeol());
			}
			if (p + 1 >= buf + sizeof(buf) - 1) {
				yyerror("string too long");
				return (findeol());
			}
			*p++ = c;
		}
		yylval.v.string = strdup(buf);
		if (yylval.v.string == NULL)
			err(1, "yylex: strdup");
		return (STRING);
	}

#define allowed_to_end_number(x) \
	(isspace(x) || x == ')' || x ==',' || x == '/' || x == '}' || x == '=')

	if (c == '-' || isdigit(c)) {
		do {
			*p++ = c;
			if ((unsigned)(p-buf) >= sizeof(buf)) {
				yyerror("string too long");
				return (findeol());
			}
		} while ((c = lgetc(0)) != EOF && isdigit(c));
		lungetc(c);
		if (p == buf + 1 && buf[0] == '-')
			goto nodigits;
		if (c == EOF || allowed_to_end_number(c)) {
			const char *errstr = NULL;

			*p = '\0';
			yylval.v.number = strtonum(buf, LLONG_MIN,
			    LLONG_MAX, &errstr);
			if (errstr) {
				yyerror("\"%s\" invalid number: %s",
				    buf, errstr);
				return (findeol());
			}
			return (NUMBER);
		} else {
nodigits:
			while (p > buf + 1)
				lungetc(*--p);
			c = *--p;
			if (c == '-')
				return (c);
		}
	}

#define allowed_in_string(x) \
	(isalnum(x) || (ispunct(x) && x != '(' && x != ')' && \
	x != '{' && x != '}' && x != '<' && x != '>' && \
	x != '!' && x != '=' && x != '/' && x != '#' && \
	x != ','))

	if (isalnum(c) || c == ':' || c == '_' || c == '*') {
		do {
			*p++ = c;
			if ((unsigned)(p-buf) >= sizeof(buf)) {
				yyerror("string too long");
				return (findeol());
			}
		} while ((c = lgetc(0)) != EOF && (allowed_in_string(c)));
		lungetc(c);
		*p = '\0';
		if ((token = lookup(buf)) == STRING)
			if ((yylval.v.string = strdup(buf)) == NULL)
				err(1, "yylex: strdup");
		return (token);
	}
	if (c == '\n') {
		yylval.lineno = file->lineno;
		file->lineno++;
	}
	if (c == EOF)
		return (0);
	return (c);
}

struct file *
pushfile(const char *name)
{
	struct file	*nfile;

	if ((nfile = calloc(1, sizeof(struct file))) == NULL)
		return (NULL);
	if ((nfile->name = strdup(name)) == NULL) {
		free(nfile);
		return (NULL);
	}
	if ((nfile->stream = fopen(nfile->name, "r")) == NULL) {
		free(nfile->name);
		free(nfile);
		return (NULL);
	}
	nfile->lineno = 1;
	TAILQ_INSERT_TAIL(&files, nfile, entry);
	return (nfile);
}

int
popfile(void)
{
	struct file	*prev;

	if ((prev = TAILQ_PREV(file, files, entry)) != NULL)
		prev->errors += file->errors;

	TAILQ_REMOVE(&files, file, entry);
	fclose(file->stream);
	free(file->name);
	free(file);
	file = prev;
	return (file ? 0 : EOF);
}

char *
parse_tapedev(const char *filename, const char *changer, int drive)
{
	struct changer	*p;
	char		*tapedev = NULL;
	int		 errors = 0;

	TAILQ_INIT(&changers);

	if ((file = pushfile(filename)) == NULL) {
		warnx("cannot open the main config file!");
		goto guess;
	}
	topfile = file;

	yyparse();
	errors = file->errors;
	popfile();

	TAILQ_FOREACH(p, &changers, entry) {
		if (strcmp(basename(changer), p->name) == 0) {
			if (drive >= 0 && drive < p->drivecnt) {
				if (asprintf(&tapedev, "/dev/%s",
				     p->drives[drive]) == -1)
					errx(1, "malloc failed");
			} else
				tapedev = NULL;
		}
	}

guess:
	/* if no device found, do the default of /dev/rstX */
	if (tapedev == NULL)
		if (asprintf(&tapedev, "/dev/rst%d", drive) == -1)
			errx(1, "malloc failed");
	return (tapedev);
}

struct changer *
new_changer(char *name)
{
	struct changer	*p;

	if ((p = calloc(1, sizeof(*p))) == NULL)
		err(1, NULL);

	if ((p->name = strdup(name)) == NULL)
		err(1, NULL);

	return (p);
}




Generated by: GCOVR (Version 3.3)

Line	Branch	Exec	Source
1			/* $OpenBSD: parse.y,v 1.20 2014/11/20 05:51:20 jsg Exp $ */
2
3			/*
4			* Copyright (c) 2006 Bob Beck <beck@openbsd.org>
5			* Copyright (c) 2002-2006 Henning Brauer <henning@openbsd.org>
6			* Copyright (c) 2001 Markus Friedl. All rights reserved.
7			* Copyright (c) 2001 Daniel Hartmeier. All rights reserved.
8			* Copyright (c) 2001 Theo de Raadt. All rights reserved.
9			*
10			* Permission to use, copy, modify, and distribute this software for any
11			* purpose with or without fee is hereby granted, provided that the above
12			* copyright notice and this permission notice appear in all copies.
13			*
14			* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
15			* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
16			* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
17			* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
18			* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
19			* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
20			* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
21			*/
22
23			%{
24			#include <sys/types.h>
25			#include <sys/socket.h>
26			#include <sys/queue.h>
27
28			#include <ctype.h>
29			#include <err.h>
30			#include <libgen.h>
31			#include <limits.h>
32			#include <stdarg.h>
33			#include <stdio.h>
34			#include <string.h>
35
36			TAILQ_HEAD(files, file) files = TAILQ_HEAD_INITIALIZER(files);
37			static struct file {
38			TAILQ_ENTRY(file) entry;
39			FILE *stream;
40			char *name;
41			int lineno;
42			int errors;
43			} file, topfile;
44			struct file pushfile(const char );
45			int popfile(void);
46			int yyparse(void);
47			int yylex(void);
48			int yyerror(const char *, ...)
49			__attribute__((__format__ (printf, 1, 2)))
50			__attribute__((__nonnull__ (1)));
51			int kw_cmp(const void , const void );
52			int lookup(char *);
53			int lgetc(int);
54			int lungetc(int);
55			int findeol(void);
56			char parse_tapedev(const char , const char *, int);
57			struct changer new_changer(char );
58
59			struct changer {
60			TAILQ_ENTRY(changer) entry;
61			char *name;
62			char **drives;
63			u_int drivecnt;
64			};
65			TAILQ_HEAD(changers, changer) changers;
66			struct changer *curchanger;
67
68			typedef struct {
69			union {
70			int64_t number;
71			char *string;
72			} v;
73			int lineno;
74			} YYSTYPE;
75
76			%}
77
78			%token CHANGER
79			%token DRIVE
80			%token ERROR
81			%token <v.string> STRING
82			%token <v.number> NUMBER
83			%%
84
85			grammar : /* empty */
86			\| grammar '\n'
87			\| grammar main '\n'
88			\| grammar error '\n' { file->errors++; }
89			;
90
91			optnl : '\n' optnl
92			\|
93			;
94
95			nl : '\n' optnl
96			;
97
98			main : CHANGER STRING optnl '{' optnl {
99			curchanger = new_changer($2);
100			}
101			changeropts_l '}' {
102			TAILQ_INSERT_TAIL(&changers, curchanger, entry);
103			curchanger = NULL;
104			}
105			;
106
107			changeropts_l : changeropts_l changeroptsl
108			\| changeroptsl
109			;
110
111			changeroptsl : changeropts nl
112			\| error nl
113			;
114
115			changeropts : DRIVE STRING {
116			void *newp;
117
118			if ((newp = reallocarray(curchanger->drives,
119			curchanger->drivecnt + 1,
120			sizeof(curchanger->drives))) == NULL)
121			err(1, NULL);
122			curchanger->drives = newp;
123			if ((curchanger->drives[curchanger->drivecnt] =
124			strdup($2)) == NULL)
125			err(1, NULL);
126			curchanger->drivecnt++;
127			free($2);
128			}
129			;
130
131			%%
132
133			struct keywords {
134			const char *k_name;
135			int k_val;
136			};
137
138			int
139			yyerror(const char *fmt, ...)
140			{
141			va_list ap;
142			char *msg;
143
144			file->errors++;
145			va_start(ap, fmt);
146			if (vasprintf(&msg, fmt, ap) == -1)
147			err(1, "yyerror vasprintf");
148			va_end(ap);
149			err(1, "%s:%d: %s", file->name, yylval.lineno, msg);
150			free(msg);
151			return (0);
152			}
153
154			int
155			kw_cmp(const void k, const void e)
156			{
157			return (strcmp(k, ((const struct keywords *)e)->k_name));
158			}
159
160			int
161			lookup(char *s)
162			{
163			/* this has to be sorted always */
164			static const struct keywords keywords[] = {
165			{ "changer", CHANGER},
166			{ "drive", DRIVE}
167			};
168			const struct keywords *p;
169
170			p = bsearch(s, keywords, sizeof(keywords)/sizeof(keywords[0]),
171			sizeof(keywords[0]), kw_cmp);
172
173			if (p)
174			return (p->k_val);
175			else
176			return (STRING);
177			}
178
179			#define MAXPUSHBACK 128
180
181			u_char *parsebuf;
182			int parseindex;
183			u_char pushback_buffer[MAXPUSHBACK];
184			int pushback_index = 0;
185
186			int
187			lgetc(int quotec)
188			{
189			int c, next;
190
191			if (parsebuf) {
192			/* Read character from the parsebuffer instead of input. */
193			if (parseindex >= 0) {
194			c = parsebuf[parseindex++];
195			if (c != '\0')
196			return (c);
197			parsebuf = NULL;
198			} else
199			parseindex++;
200			}
201
202			if (pushback_index)
203			return (pushback_buffer[--pushback_index]);
204
205			if (quotec) {
206			if ((c = getc(file->stream)) == EOF) {
207			yyerror("reached end of file while parsing "
208			"quoted string");
209			if (file == topfile \|\| popfile() == EOF)
210			return (EOF);
211			return (quotec);
212			}
213			return (c);
214			}
215
216			while ((c = getc(file->stream)) == '\\') {
217			next = getc(file->stream);
218			if (next != '\n') {
219			c = next;
220			break;
221			}
222			yylval.lineno = file->lineno;
223			file->lineno++;
224			}
225
226			while (c == EOF) {
227			if (file == topfile \|\| popfile() == EOF)
228			return (EOF);
229			c = getc(file->stream);
230			}
231			return (c);
232			}
233
234			int
235			lungetc(int c)
236			{
237			if (c == EOF)
238			return (EOF);
239			if (parsebuf) {
240			parseindex--;
241			if (parseindex >= 0)
242			return (c);
243			}
244			if (pushback_index < MAXPUSHBACK-1)
245			return (pushback_buffer[pushback_index++] = c);
246			else
247			return (EOF);
248			}
249
250			int
251			findeol(void)
252			{
253			int c;
254
255			parsebuf = NULL;
256			pushback_index = 0;
257
258			/* skip to either EOF or the first real EOL */
259			while (1) {
260			c = lgetc(0);
261			if (c == '\n') {
262			file->lineno++;
263			break;
264			}
265			if (c == EOF)
266			break;
267			}
268			return (ERROR);
269			}
270
271			int
272			yylex(void)
273			{
274			u_char buf[8096];
275			u_char *p;
276			int quotec, next, c;
277			int token;
278
279			p = buf;
280			while ((c = lgetc(0)) == ' ' \|\| c == '\t')
281			; /* nothing */
282
283			yylval.lineno = file->lineno;
284			if (c == '#')
285			while ((c = lgetc(0)) != '\n' && c != EOF)
286			; /* nothing */
287
288			switch (c) {
289			case '\'':
290			case '"':
291			quotec = c;
292			while (1) {
293			if ((c = lgetc(quotec)) == EOF)
294			return (0);
295			if (c == '\n') {
296			file->lineno++;
297			continue;
298			} else if (c == '\\') {
299			if ((next = lgetc(quotec)) == EOF)
300			return (0);
301			if (next == quotec \|\| c == ' ' \|\| c == '\t')
302			c = next;
303			else if (next == '\n')
304			continue;
305			else
306			lungetc(next);
307			} else if (c == quotec) {
308			*p = '\0';
309			break;
310			} else if (c == '\0') {
311			yyerror("syntax error");
312			return (findeol());
313			}
314			if (p + 1 >= buf + sizeof(buf) - 1) {
315			yyerror("string too long");
316			return (findeol());
317			}
318			*p++ = c;
319			}
320			yylval.v.string = strdup(buf);
321			if (yylval.v.string == NULL)
322			err(1, "yylex: strdup");
323			return (STRING);
324			}
325
326			#define allowed_to_end_number(x) \
327			(isspace(x) \|\| x == ')' \|\| x ==',' \|\| x == '/' \|\| x == '}' \|\| x == '=')
328
329			if (c == '-' \|\| isdigit(c)) {
330			do {
331			*p++ = c;
332			if ((unsigned)(p-buf) >= sizeof(buf)) {
333			yyerror("string too long");
334			return (findeol());
335			}
336			} while ((c = lgetc(0)) != EOF && isdigit(c));
337			lungetc(c);
338			if (p == buf + 1 && buf[0] == '-')
339			goto nodigits;
340			if (c == EOF \|\| allowed_to_end_number(c)) {
341			const char *errstr = NULL;
342
343			*p = '\0';
344			yylval.v.number = strtonum(buf, LLONG_MIN,
345			LLONG_MAX, &errstr);
346			if (errstr) {
347			yyerror("\"%s\" invalid number: %s",
348			buf, errstr);
349			return (findeol());
350			}
351			return (NUMBER);
352			} else {
353			nodigits:
354			while (p > buf + 1)
355			lungetc(*--p);
356			c = *--p;
357			if (c == '-')
358			return (c);
359			}
360			}
361
362			#define allowed_in_string(x) \
363			(isalnum(x) \|\| (ispunct(x) && x != '(' && x != ')' && \
364			x != '{' && x != '}' && x != '<' && x != '>' && \
365			x != '!' && x != '=' && x != '/' && x != '#' && \
366			x != ','))
367
368			if (isalnum(c) \|\| c == ':' \|\| c == '_' \|\| c == '*') {
369			do {
370			*p++ = c;
371			if ((unsigned)(p-buf) >= sizeof(buf)) {
372			yyerror("string too long");
373			return (findeol());
374			}
375			} while ((c = lgetc(0)) != EOF && (allowed_in_string(c)));
376			lungetc(c);
377			*p = '\0';
378			if ((token = lookup(buf)) == STRING)
379			if ((yylval.v.string = strdup(buf)) == NULL)
380			err(1, "yylex: strdup");
381			return (token);
382			}
383			if (c == '\n') {
384			yylval.lineno = file->lineno;
385			file->lineno++;
386			}
387			if (c == EOF)
388			return (0);
389			return (c);
390			}
391
392			struct file *
393			pushfile(const char *name)
394			{
395			struct file *nfile;
396
397			if ((nfile = calloc(1, sizeof(struct file))) == NULL)
398			return (NULL);
399			if ((nfile->name = strdup(name)) == NULL) {
400			free(nfile);
401			return (NULL);
402			}
403			if ((nfile->stream = fopen(nfile->name, "r")) == NULL) {
404			free(nfile->name);
405			free(nfile);
406			return (NULL);
407			}
408			nfile->lineno = 1;
409			TAILQ_INSERT_TAIL(&files, nfile, entry);
410			return (nfile);
411			}
412
413			int
414			popfile(void)
415			{
416			struct file *prev;
417
418			if ((prev = TAILQ_PREV(file, files, entry)) != NULL)
419			prev->errors += file->errors;
420
421			TAILQ_REMOVE(&files, file, entry);
422			fclose(file->stream);
423			free(file->name);
424			free(file);
425			file = prev;
426			return (file ? 0 : EOF);
427			}
428
429			char *
430			parse_tapedev(const char filename, const char changer, int drive)
431			{
432			struct changer *p;
433			char *tapedev = NULL;
434			int errors = 0;
435
436			TAILQ_INIT(&changers);
437
438			if ((file = pushfile(filename)) == NULL) {
439			warnx("cannot open the main config file!");
440			goto guess;
441			}
442			topfile = file;
443
444			yyparse();
445			errors = file->errors;
446			popfile();
447
448			TAILQ_FOREACH(p, &changers, entry) {
449			if (strcmp(basename(changer), p->name) == 0) {
450			if (drive >= 0 && drive < p->drivecnt) {
451			if (asprintf(&tapedev, "/dev/%s",
452			p->drives[drive]) == -1)
453			errx(1, "malloc failed");
454			} else
455			tapedev = NULL;
456			}
457			}
458
459			guess:
460			/* if no device found, do the default of /dev/rstX */
461			if (tapedev == NULL)
462			if (asprintf(&tapedev, "/dev/rst%d", drive) == -1)
463			errx(1, "malloc failed");
464			return (tapedev);
465			}
466
467			struct changer *
468			new_changer(char *name)
469			{
470			struct changer *p;
471
472			if ((p = calloc(1, sizeof(*p))) == NULL)
473			err(1, NULL);
474
475			if ((p->name = strdup(name)) == NULL)
476			err(1, NULL);
477
478			return (p);
479			}
480
481