Head

GCC Code Coverage Report

Directory:	./		Exec	Total	Coverage
File:	usr.bin/less/less/../filename.c	Lines:	81	289	28.0 %
Date:	2017-11-13	Branches:	34	187	18.2 %


/*
 * Copyright (C) 1984-2012  Mark Nudelman
 * Modified for use with illumos by Garrett D'Amore.
 * Copyright 2014 Garrett D'Amore <garrett@damore.org>
 *
 * You may distribute under the terms of either the GNU General Public
 * License or the Less License, as specified in the README file.
 *
 * For more information, see the README file.
 */

/*
 * Routines to mess around with filenames (and files).
 * Much of this is very OS dependent.
 *
 * Modified for illumos/POSIX -- it uses native glob(3C) rather than
 * popen to a shell to perform the expansion.
 */

#include <sys/stat.h>

#include <glob.h>
#include <stdarg.h>

#include "less.h"

extern int force_open;
extern int secure;
extern int use_lessopen;
extern int ctldisp;
extern int utf_mode;
extern IFILE curr_ifile;
extern IFILE old_ifile;
extern char openquote;
extern char closequote;

/*
 * Remove quotes around a filename.
 */
char *
shell_unquote(char *str)
{
	char *name;
	char *p;

	name = p = ecalloc(strlen(str)+1, sizeof (char));
	if (*str == openquote) {
		str++;
		while (*str != '\0') {
			if (*str == closequote) {
				if (str[1] != closequote)
					break;
				str++;
			}
			*p++ = *str++;
		}
	} else {
		char *esc = get_meta_escape();
		int esclen = strlen(esc);
		while (*str != '\0') {
			if (esclen > 0 && strncmp(str, esc, esclen) == 0)
				str += esclen;
			*p++ = *str++;
		}
	}
	*p = '\0';
	return (name);
}

/*
 * Get the shell's escape character.
 */
char *
get_meta_escape(void)
{
	char *s;

	s = lgetenv("LESSMETAESCAPE");
	if (s == NULL)
		s = "\\";
	return (s);
}

/*
 * Get the characters which the shell considers to be "metacharacters".
 */
static char *
metachars(void)
{
	static char *mchars = NULL;

	if (mchars == NULL) {
		mchars = lgetenv("LESSMETACHARS");
		if (mchars == NULL)
			mchars = DEF_METACHARS;
	}
	return (mchars);
}

/*
 * Is this a shell metacharacter?
 */
static int
metachar(char c)
{
	return (strchr(metachars(), c) != NULL);
}

/*
 * Insert a backslash before each metacharacter in a string.
 */
char *
shell_quote(const char *s)
{
	const char *p;
	char *r;
	char *newstr;
	int len;
	char *esc = get_meta_escape();
	int esclen = strlen(esc);
	int use_quotes = 0;
	int have_quotes = 0;

	/*
	 * Determine how big a string we need to allocate.
	 */
	len = 1; /* Trailing null byte */
	for (p = s; *p != '\0'; p++) {
		len++;
		if (*p == openquote || *p == closequote)
			have_quotes = 1;
		if (metachar(*p)) {
			if (esclen == 0) {
				/*
				 * We've got a metachar, but this shell
				 * doesn't support escape chars.  Use quotes.
				 */
				use_quotes = 1;
			} else {
				/*
				 * Allow space for the escape char.
				 */
				len += esclen;
			}
		}
	}
	/*
	 * Allocate and construct the new string.
	 */
	if (use_quotes) {
		/* We can't quote a string that contains quotes. */
		if (have_quotes)
			return (NULL);
		newstr  = easprintf("%c%s%c", openquote, s, closequote);
	} else {
		newstr = r = ecalloc(len, sizeof (char));
		while (*s != '\0') {
			if (metachar(*s)) {
				/*
				 * Add the escape char.
				 */
				(void) strlcpy(r, esc, newstr + len - p);
				r += esclen;
			}
			*r++ = *s++;
		}
		*r = '\0';
	}
	return (newstr);
}

/*
 * Return a pathname that points to a specified file in a specified directory.
 * Return NULL if the file does not exist in the directory.
 */
static char *
dirfile(const char *dirname, const char *filename)
{
	char *pathname;
	char *qpathname;
	int f;

	if (dirname == NULL || *dirname == '\0')
		return (NULL);
	/*
	 * Construct the full pathname.
	 */
	pathname = easprintf("%s/%s", dirname, filename);
	/*
	 * Make sure the file exists.
	 */
	qpathname = shell_unquote(pathname);
	f = open(qpathname, O_RDONLY);
	if (f < 0) {
		free(pathname);
		pathname = NULL;
	} else {
		(void) close(f);
	}
	free(qpathname);
	return (pathname);
}

/*
 * Return the full pathname of the given file in the "home directory".
 */
char *
homefile(char *filename)
{
	return (dirfile(lgetenv("HOME"), filename));
}

/*
 * Expand a string, substituting any "%" with the current filename,
 * and any "#" with the previous filename.
 * But a string of N "%"s is just replaced with N-1 "%"s.
 * Likewise for a string of N "#"s.
 * {{ This is a lot of work just to support % and #. }}
 */
char *
fexpand(char *s)
{
	char *fr, *to;
	int n;
	char *e;
	IFILE ifile;

#define	fchar_ifile(c) \
	((c) == '%' ? curr_ifile : (c) == '#' ? old_ifile : NULL)

	/*
	 * Make one pass to see how big a buffer we
	 * need to allocate for the expanded string.
	 */
	n = 0;
	for (fr = s; *fr != '\0'; fr++) {
		switch (*fr) {
		case '%':
		case '#':
			if (fr > s && fr[-1] == *fr) {
				/*
				 * Second (or later) char in a string
				 * of identical chars.  Treat as normal.
				 */
				n++;
			} else if (fr[1] != *fr) {
				/*
				 * Single char (not repeated).  Treat specially.
				 */
				ifile = fchar_ifile(*fr);
				if (ifile == NULL)
					n++;
				else
					n += strlen(get_filename(ifile));
			}
			/*
			 * Else it is the first char in a string of
			 * identical chars.  Just discard it.
			 */
			break;
		default:
			n++;
			break;
		}
	}

	e = ecalloc(n+1, sizeof (char));

	/*
	 * Now copy the string, expanding any "%" or "#".
	 */
	to = e;
	for (fr = s; *fr != '\0'; fr++) {
		switch (*fr) {
		case '%':
		case '#':
			if (fr > s && fr[-1] == *fr) {
				*to++ = *fr;
			} else if (fr[1] != *fr) {
				ifile = fchar_ifile(*fr);
				if (ifile == NULL) {
					*to++ = *fr;
				} else {
					(void) strlcpy(to, get_filename(ifile),
					    e + n + 1 - to);
					to += strlen(to);
				}
			}
			break;
		default:
			*to++ = *fr;
			break;
		}
	}
	*to = '\0';
	return (e);
}

/*
 * Return a blank-separated list of filenames which "complete"
 * the given string.
 */
char *
fcomplete(char *s)
{
	char *fpat;
	char *qs;

	if (secure)
		return (NULL);
	/*
	 * Complete the filename "s" by globbing "s*".
	 */
	fpat =  easprintf("%s*", s);

	qs = lglob(fpat);
	s = shell_unquote(qs);
	if (strcmp(s, fpat) == 0) {
		/*
		 * The filename didn't expand.
		 */
		free(qs);
		qs = NULL;
	}
	free(s);
	free(fpat);
	return (qs);
}

/*
 * Try to determine if a file is "binary".
 * This is just a guess, and we need not try too hard to make it accurate.
 */
int
bin_file(int f)
{
	int n;
	int bin_count = 0;
	char data[256];
	char *p;
	char *pend;

	if (!seekable(f))
		return (0);
	if (lseek(f, (off_t)0, SEEK_SET) == (off_t)-1)
		return (0);
	n = read(f, data, sizeof (data));
	pend = &data[n];
	for (p = data; p < pend; ) {
		LWCHAR c = step_char(&p, +1, pend);
		if (ctldisp == OPT_ONPLUS && IS_CSI_START(c)) {
			do {
				c = step_char(&p, +1, pend);
			} while (p < pend && is_ansi_middle(c));
		} else if (binary_char(c))
			bin_count++;
	}
	/*
	 * Call it a binary file if there are more than 5 binary characters
	 * in the first 256 bytes of the file.
	 */
	return (bin_count > 5);
}

/*
 * Read a string from a file.
 * Return a pointer to the string in memory.
 */
static char *
readfd(FILE *fd)
{
	int len;
	int ch;
	char *buf;
	char *p;

	/*
	 * Make a guess about how many chars in the string
	 * and allocate a buffer to hold it.
	 */
	len = 100;
	buf = ecalloc(len, sizeof (char));
	for (p = buf; ; p++) {
		if ((ch = getc(fd)) == '\n' || ch == EOF)
			break;
		if (p >= buf + len-1) {
			/*
			 * The string is too big to fit in the buffer we have.
			 * Allocate a new buffer, twice as big.
			 */
			len *= 2;
			*p = '\0';
			p = ecalloc(len, sizeof (char));
			strlcpy(p, buf, len);
			free(buf);
			buf = p;
			p = buf + strlen(buf);
		}
		*p = (char)ch;
	}
	*p = '\0';
	return (buf);
}

/*
 * Execute a shell command.
 * Return a pointer to a pipe connected to the shell command's standard output.
 */
static FILE *
shellcmd(char *cmd)
{
	FILE *fd;

	char *shell;

	shell = lgetenv("SHELL");
	if (shell != NULL && *shell != '\0') {
		char *scmd;
		char *esccmd;

		/*
		 * Read the output of <$SHELL -c cmd>.
		 * Escape any metacharacters in the command.
		 */
		esccmd = shell_quote(cmd);
		if (esccmd == NULL) {
			fd = popen(cmd, "r");
		} else {
			scmd = easprintf("%s -c %s", shell, esccmd);
			free(esccmd);
			fd = popen(scmd, "r");
			free(scmd);
		}
	} else {
		fd = popen(cmd, "r");
	}
	/*
	 * Redirection in `popen' might have messed with the
	 * standard devices.  Restore binary input mode.
	 */
	return (fd);
}

/*
 * Expand a filename, doing any system-specific metacharacter substitutions.
 */
char *
lglob(char *filename)
{
	char *gfilename;
	char *ofilename;
	glob_t list;
	int i;
	int length;
	char *p;
	char *qfilename;

	ofilename = fexpand(filename);
	if (secure)
		return (ofilename);
	filename = shell_unquote(ofilename);

	/*
	 * The globbing function returns a list of names.
	 */

#ifndef	GLOB_TILDE
#define	GLOB_TILDE	0
#endif
#ifndef	GLOB_LIMIT
#define	GLOB_LIMIT	0
#endif
	if (glob(filename, GLOB_TILDE | GLOB_LIMIT, NULL, &list) != 0) {
		free(filename);
		return (ofilename);
	}
	length = 1; /* Room for trailing null byte */
	for (i = 0; i < list.gl_pathc; i++) {
		p = list.gl_pathv[i];
		qfilename = shell_quote(p);
		if (qfilename != NULL) {
			length += strlen(qfilename) + 1;
			free(qfilename);
		}
	}
	gfilename = ecalloc(length, sizeof (char));
	for (i = 0; i < list.gl_pathc; i++) {
		p = list.gl_pathv[i];
		qfilename = shell_quote(p);
		if (qfilename != NULL) {
			if (i != 0) {
				(void) strlcat(gfilename, " ", length);
			}
			(void) strlcat(gfilename, qfilename, length);
			free(qfilename);
		}
	}
	globfree(&list);
	free(filename);
	free(ofilename);
	return (gfilename);
}

/*
 * Expand LESSOPEN or LESSCLOSE.  Returns a newly allocated string
 * on success, NULL otherwise.
 */
static char *
expand_pct_s(const char *fmt, ...)
{
	int		n;
	int		len;
	char		*r, *d;
	const char	*f[3];		/* max expansions + 1 for NULL */
	va_list		ap;

	va_start(ap, fmt);
	for (n = 0; n < ((sizeof (f)/sizeof (f[0])) - 1); n++) {
		f[n] = (const char *)va_arg(ap, const char *);
		if (f[n] == NULL) {
			break;
		}
	}
	va_end(ap);
	f[n] = NULL;	/* terminate list */

	len = strlen(fmt) + 1;
	for (n = 0; f[n] != NULL; n++) {
		len += strlen(f[n]);	/* technically could -2 for "%s" */
	}
	r = ecalloc(len, sizeof (char));

	for (n = 0, d = r; *fmt != 0; ) {
		if (*fmt != '%') {
			*d++ = *fmt++;
			continue;
		}
		fmt++;
		/* Permit embedded "%%" */
		switch (*fmt) {
		case '%':
			*d++ = '%';
			fmt++;
			break;
		case 's':
			if (f[n] == NULL) {
				va_end(ap);
				free(r);
				return (NULL);
			}
			(void) strlcpy(d, f[n++], r + len - d);
			fmt++;
			d += strlen(d);
			break;
		default:
			va_end(ap);
			free(r);
			return (NULL);
		}
	}
	*d = '\0';
	return (r);
}

/*
 * See if we should open a "replacement file"
 * instead of the file we're about to open.
 */
char *
open_altfile(char *filename, int *pf, void **pfd)
{
	char *lessopen;
	char *cmd;
	FILE *fd;
	int returnfd = 0;

	if (!use_lessopen || secure)
		return (NULL);
	ch_ungetchar(-1);
	if ((lessopen = lgetenv("LESSOPEN")) == NULL)
		return (NULL);
	while (*lessopen == '|') {
		/*
		 * If LESSOPEN starts with a |, it indicates
		 * a "pipe preprocessor".
		 */
		lessopen++;
		returnfd++;
	}
	if (*lessopen == '-') {
		/*
		 * Lessopen preprocessor will accept "-" as a filename.
		 */
		lessopen++;
	} else {
		if (strcmp(filename, "-") == 0)
			return (NULL);
	}

	if ((cmd = expand_pct_s(lessopen, filename, NULL)) == NULL) {
		error("Invalid LESSOPEN variable", NULL);
		return (NULL);
	}
	fd = shellcmd(cmd);
	free(cmd);
	if (fd == NULL) {
		/*
		 * Cannot create the pipe.
		 */
		return (NULL);
	}
	if (returnfd) {
		int f;
		char c;

		/*
		 * Read one char to see if the pipe will produce any data.
		 * If it does, push the char back on the pipe.
		 */
		f = fileno(fd);
		if (read(f, &c, 1) != 1) {
			/*
			 * Pipe is empty.
			 * If more than 1 pipe char was specified,
			 * the exit status tells whether the file itself
			 * is empty, or if there is no alt file.
			 * If only one pipe char, just assume no alt file.
			 */
			int status = pclose(fd);
			if (returnfd > 1 && status == 0) {
				*pfd = NULL;
				*pf = -1;
				return (estrdup(FAKE_EMPTYFILE));
			}
			return (NULL);
		}
		ch_ungetchar(c);
		*pfd = (void *) fd;
		*pf = f;
		return (estrdup("-"));
	}
	cmd = readfd(fd);
	pclose(fd);
	if (*cmd == '\0')
		/*
		 * Pipe is empty.  This means there is no alt file.
		 */
		return (NULL);
	return (cmd);
}

/*
 * Close a replacement file.
 */
void
close_altfile(char *altfilename, char *filename, void *pipefd)
{
	char *lessclose;
	FILE *fd;
	char *cmd;

	if (secure)
		return;
	if (pipefd != NULL) {
		pclose((FILE *)pipefd);
	}
	if ((lessclose = lgetenv("LESSCLOSE")) == NULL)
		return;
	cmd = expand_pct_s(lessclose, filename, altfilename, NULL);
	if (cmd == NULL) {
		error("Invalid LESSCLOSE variable", NULL);
		return;
	}
	fd = shellcmd(cmd);
	free(cmd);
	if (fd != NULL)
		(void) pclose(fd);
}

/*
 * Is the specified file a directory?
 */
int
is_dir(char *filename)
{
	int isdir = 0;
	int r;
	struct stat statbuf;

	filename = shell_unquote(filename);

	r = stat(filename, &statbuf);
	isdir = (r >= 0 && S_ISDIR(statbuf.st_mode));
	free(filename);
	return (isdir);
}

/*
 * Returns NULL if the file can be opened and
 * is an ordinary file, otherwise an error message
 * (if it cannot be opened or is a directory, etc.)
 */
char *
bad_file(char *filename)
{
	char *m = NULL;

	filename = shell_unquote(filename);
	if (!force_open && is_dir(filename)) {
		m = easprintf("%s is a directory", filename);
	} else {
		int r;
		struct stat statbuf;

		r = stat(filename, &statbuf);
		if (r < 0) {
			m = errno_message(filename);
		} else if (force_open) {
			m = NULL;
		} else if (!S_ISREG(statbuf.st_mode)) {
			m = easprintf("%s is not a regular file (use -f to "
			    "see it)", filename);
		}
	}
	free(filename);
	return (m);
}

/*
 * Return the size of a file, as cheaply as possible.
 */
off_t
filesize(int f)
{
	struct stat statbuf;

	if (fstat(f, &statbuf) >= 0)
		return (statbuf.st_size);
	return (-1);
}

/*
 * Return last component of a pathname.
 */
char *
last_component(char *name)
{
	char *slash;

	for (slash = name + strlen(name); slash > name; ) {
		--slash;
		if (*slash == '/')
			return (slash + 1);
	}
	return (name);
}


Generated by: GCOVR (Version 3.3)

Line	Branch	Exec	Source
1			/*
2			* Copyright (C) 1984-2012 Mark Nudelman
3			* Modified for use with illumos by Garrett D'Amore.
4			* Copyright 2014 Garrett D'Amore <garrett@damore.org>
5			*
6			* You may distribute under the terms of either the GNU General Public
7			* License or the Less License, as specified in the README file.
8			*
9			* For more information, see the README file.
10			*/
11
12			/*
13			* Routines to mess around with filenames (and files).
14			* Much of this is very OS dependent.
15			*
16			* Modified for illumos/POSIX -- it uses native glob(3C) rather than
17			* popen to a shell to perform the expansion.
18			*/
19
20			#include <sys/stat.h>
21
22			#include <glob.h>
23			#include <stdarg.h>
24
25			#include "less.h"
26
27			extern int force_open;
28			extern int secure;
29			extern int use_lessopen;
30			extern int ctldisp;
31			extern int utf_mode;
32			extern IFILE curr_ifile;
33			extern IFILE old_ifile;
34			extern char openquote;
35			extern char closequote;
36
37			/*
38			* Remove quotes around a filename.
39			*/
40			char *
41			shell_unquote(char *str)
42			{
43			char *name;
44			char *p;
45
46		80	name = p = ecalloc(strlen(str)+1, sizeof (char));
47	✗✓	40	if (*str == openquote) {
48			str++;
49			while (*str != '\0') {
50			if (*str == closequote) {
51			if (str[1] != closequote)
52			break;
53			str++;
54			}
55			p++ = str++;
56			}
57			} else {
58		40	char *esc = get_meta_escape();
59		40	int esclen = strlen(esc);
60	✓✓	1150	while (*str != '\0') {
61	✓✗✗✓	1070	if (esclen > 0 && strncmp(str, esc, esclen) == 0)
62			str += esclen;
63		535	p++ = str++;
64			}
65			}
66		40	*p = '\0';
67		40	return (name);
68			}
69
70			/*
71			* Get the shell's escape character.
72			*/
73			char *
74			get_meta_escape(void)
75			{
76			char *s;
77
78		96	s = lgetenv("LESSMETAESCAPE");
79		48	if (s == NULL)
80			s = "\\";
81		48	return (s);
82			}
83
84			/*
85			* Get the characters which the shell considers to be "metacharacters".
86			*/
87			static char *
88			metachars(void)
89			{
90			static char *mchars = NULL;
91
92	✓✓	468	if (mchars == NULL) {
93		8	mchars = lgetenv("LESSMETACHARS");
94		8	if (mchars == NULL)
95			mchars = DEF_METACHARS;
96		8	}
97		234	return (mchars);
98			}
99
100			/*
101			* Is this a shell metacharacter?
102			*/
103			static int
104			metachar(char c)
105			{
106		468	return (strchr(metachars(), c) != NULL);
107			}
108
109			/*
110			* Insert a backslash before each metacharacter in a string.
111			*/
112			char *
113			shell_quote(const char *s)
114			{
115			const char *p;
116			char *r;
117			char *newstr;
118			int len;
119		16	char *esc = get_meta_escape();
120		8	int esclen = strlen(esc);
121			int use_quotes = 0;
122			int have_quotes = 0;
123
124			/*
125			* Determine how big a string we need to allocate.
126			*/
127			len = 1; /* Trailing null byte */
128	✓✓	250	for (p = s; *p != '\0'; p++) {
129		117	len++;
130	✓✗✗✓	234	if (p == openquote \|\| p == closequote)
131			have_quotes = 1;
132	✗✓	117	if (metachar(*p)) {
133			if (esclen == 0) {
134			/*
135			* We've got a metachar, but this shell
136			* doesn't support escape chars. Use quotes.
137			*/
138			use_quotes = 1;
139			} else {
140			/*
141			* Allow space for the escape char.
142			*/
143			len += esclen;
144			}
145			}
146			}
147			/*
148			* Allocate and construct the new string.
149			*/
150	✗✓	8	if (use_quotes) {
151			/* We can't quote a string that contains quotes. */
152			if (have_quotes)
153			return (NULL);
154			newstr = easprintf("%c%s%c", openquote, s, closequote);
155			} else {
156		8	newstr = r = ecalloc(len, sizeof (char));
157	✓✓	250	while (*s != '\0') {
158	✗✓	117	if (metachar(*s)) {
159			/*
160			* Add the escape char.
161			*/
162			(void) strlcpy(r, esc, newstr + len - p);
163			r += esclen;
164			}
165		117	r++ = s++;
166			}
167		8	*r = '\0';
168			}
169		8	return (newstr);
170		8	}
171
172			/*
173			* Return a pathname that points to a specified file in a specified directory.
174			* Return NULL if the file does not exist in the directory.
175			*/
176			static char *
177			dirfile(const char dirname, const char filename)
178			{
179			char *pathname;
180			char *qpathname;
181			int f;
182
183	✓✗✗✓	24	if (dirname == NULL \|\| *dirname == '\0')
184			return (NULL);
185			/*
186			* Construct the full pathname.
187			*/
188		8	pathname = easprintf("%s/%s", dirname, filename);
189			/*
190			* Make sure the file exists.
191			*/
192		8	qpathname = shell_unquote(pathname);
193		8	f = open(qpathname, O_RDONLY);
194	✓✗	8	if (f < 0) {
195		8	free(pathname);
196			pathname = NULL;
197		8	} else {
198			(void) close(f);
199			}
200		8	free(qpathname);
201		8	return (pathname);
202		8	}
203
204			/*
205			* Return the full pathname of the given file in the "home directory".
206			*/
207			char *
208			homefile(char *filename)
209			{
210		16	return (dirfile(lgetenv("HOME"), filename));
211			}
212
213			/*
214			* Expand a string, substituting any "%" with the current filename,
215			* and any "#" with the previous filename.
216			* But a string of N "%"s is just replaced with N-1 "%"s.
217			* Likewise for a string of N "#"s.
218			* {{ This is a lot of work just to support % and #. }}
219			*/
220			char *
221			fexpand(char *s)
222			{
223			char fr, to;
224			int n;
225			char *e;
226			IFILE ifile;
227
228			#define fchar_ifile(c) \
229			((c) == '%' ? curr_ifile : (c) == '#' ? old_ifile : NULL)
230
231			/*
232			* Make one pass to see how big a buffer we
233			* need to allocate for the expanded string.
234			*/
235			n = 0;
236			for (fr = s; *fr != '\0'; fr++) {
237			switch (*fr) {
238			case '%':
239			case '#':
240			if (fr > s && fr[-1] == *fr) {
241			/*
242			* Second (or later) char in a string
243			* of identical chars. Treat as normal.
244			*/
245			n++;
246			} else if (fr[1] != *fr) {
247			/*
248			* Single char (not repeated). Treat specially.
249			*/
250			ifile = fchar_ifile(*fr);
251			if (ifile == NULL)
252			n++;
253			else
254			n += strlen(get_filename(ifile));
255			}
256			/*
257			* Else it is the first char in a string of
258			* identical chars. Just discard it.
259			*/
260			break;
261			default:
262			n++;
263			break;
264			}
265			}
266
267			e = ecalloc(n+1, sizeof (char));
268
269			/*
270			* Now copy the string, expanding any "%" or "#".
271			*/
272			to = e;
273			for (fr = s; *fr != '\0'; fr++) {
274			switch (*fr) {
275			case '%':
276			case '#':
277			if (fr > s && fr[-1] == *fr) {
278			to++ = fr;
279			} else if (fr[1] != *fr) {
280			ifile = fchar_ifile(*fr);
281			if (ifile == NULL) {
282			to++ = fr;
283			} else {
284			(void) strlcpy(to, get_filename(ifile),
285			e + n + 1 - to);
286			to += strlen(to);
287			}
288			}
289			break;
290			default:
291			to++ = fr;
292			break;
293			}
294			}
295			*to = '\0';
296			return (e);
297			}
298
299			/*
300			* Return a blank-separated list of filenames which "complete"
301			* the given string.
302			*/
303			char *
304			fcomplete(char *s)
305			{
306			char *fpat;
307			char *qs;
308
309			if (secure)
310			return (NULL);
311			/*
312			* Complete the filename "s" by globbing "s*".
313			*/
314			fpat = easprintf("%s*", s);
315
316			qs = lglob(fpat);
317			s = shell_unquote(qs);
318			if (strcmp(s, fpat) == 0) {
319			/*
320			* The filename didn't expand.
321			*/
322			free(qs);
323			qs = NULL;
324			}
325			free(s);
326			free(fpat);
327			return (qs);
328			}
329
330			/*
331			* Try to determine if a file is "binary".
332			* This is just a guess, and we need not try too hard to make it accurate.
333			*/
334			int
335			bin_file(int f)
336			{
337			int n;
338			int bin_count = 0;
339		16	char data[256];
340		8	char *p;
341			char *pend;
342
343	✗✓	8	if (!seekable(f))
344			return (0);
345	✗✓	8	if (lseek(f, (off_t)0, SEEK_SET) == (off_t)-1)
346			return (0);
347		8	n = read(f, data, sizeof (data));
348		8	pend = &data[n];
349	✓✓	4112	for (p = data; p < pend; ) {
350		2048	LWCHAR c = step_char(&p, +1, pend);
351	✗✓✗✗	2048	if (ctldisp == OPT_ONPLUS && IS_CSI_START(c)) {
352			do {
353			c = step_char(&p, +1, pend);
354			} while (p < pend && is_ansi_middle(c));
355	✗✓	2048	} else if (binary_char(c))
356			bin_count++;
357			}
358			/*
359			* Call it a binary file if there are more than 5 binary characters
360			* in the first 256 bytes of the file.
361			*/
362		8	return (bin_count > 5);
363		8	}
364
365			/*
366			* Read a string from a file.
367			* Return a pointer to the string in memory.
368			*/
369			static char *
370			readfd(FILE *fd)
371			{
372			int len;
373			int ch;
374			char *buf;
375			char *p;
376
377			/*
378			* Make a guess about how many chars in the string
379			* and allocate a buffer to hold it.
380			*/
381			len = 100;
382			buf = ecalloc(len, sizeof (char));
383			for (p = buf; ; p++) {
384			if ((ch = getc(fd)) == '\n' \|\| ch == EOF)
385			break;
386			if (p >= buf + len-1) {
387			/*
388			* The string is too big to fit in the buffer we have.
389			* Allocate a new buffer, twice as big.
390			*/
391			len *= 2;
392			*p = '\0';
393			p = ecalloc(len, sizeof (char));
394			strlcpy(p, buf, len);
395			free(buf);
396			buf = p;
397			p = buf + strlen(buf);
398			}
399			*p = (char)ch;
400			}
401			*p = '\0';
402			return (buf);
403			}
404
405			/*
406			* Execute a shell command.
407			* Return a pointer to a pipe connected to the shell command's standard output.
408			*/
409			static FILE *
410			shellcmd(char *cmd)
411			{
412			FILE *fd;
413
414			char *shell;
415
416			shell = lgetenv("SHELL");
417			if (shell != NULL && *shell != '\0') {
418			char *scmd;
419			char *esccmd;
420
421			/*
422			* Read the output of <$SHELL -c cmd>.
423			* Escape any metacharacters in the command.
424			*/
425			esccmd = shell_quote(cmd);
426			if (esccmd == NULL) {
427			fd = popen(cmd, "r");
428			} else {
429			scmd = easprintf("%s -c %s", shell, esccmd);
430			free(esccmd);
431			fd = popen(scmd, "r");
432			free(scmd);
433			}
434			} else {
435			fd = popen(cmd, "r");
436			}
437			/*
438			* Redirection in `popen' might have messed with the
439			* standard devices. Restore binary input mode.
440			*/
441			return (fd);
442			}
443
444			/*
445			* Expand a filename, doing any system-specific metacharacter substitutions.
446			*/
447			char *
448			lglob(char *filename)
449			{
450			char *gfilename;
451			char *ofilename;
452			glob_t list;
453			int i;
454			int length;
455			char *p;
456			char *qfilename;
457
458			ofilename = fexpand(filename);
459			if (secure)
460			return (ofilename);
461			filename = shell_unquote(ofilename);
462
463			/*
464			* The globbing function returns a list of names.
465			*/
466
467			#ifndef GLOB_TILDE
468			#define GLOB_TILDE 0
469			#endif
470			#ifndef GLOB_LIMIT
471			#define GLOB_LIMIT 0
472			#endif
473			if (glob(filename, GLOB_TILDE \| GLOB_LIMIT, NULL, &list) != 0) {
474			free(filename);
475			return (ofilename);
476			}
477			length = 1; /* Room for trailing null byte */
478			for (i = 0; i < list.gl_pathc; i++) {
479			p = list.gl_pathv[i];
480			qfilename = shell_quote(p);
481			if (qfilename != NULL) {
482			length += strlen(qfilename) + 1;
483			free(qfilename);
484			}
485			}
486			gfilename = ecalloc(length, sizeof (char));
487			for (i = 0; i < list.gl_pathc; i++) {
488			p = list.gl_pathv[i];
489			qfilename = shell_quote(p);
490			if (qfilename != NULL) {
491			if (i != 0) {
492			(void) strlcat(gfilename, " ", length);
493			}
494			(void) strlcat(gfilename, qfilename, length);
495			free(qfilename);
496			}
497			}
498			globfree(&list);
499			free(filename);
500			free(ofilename);
501			return (gfilename);
502			}
503
504			/*
505			* Expand LESSOPEN or LESSCLOSE. Returns a newly allocated string
506			* on success, NULL otherwise.
507			*/
508			static char *
509			expand_pct_s(const char *fmt, ...)
510			{
511			int n;
512			int len;
513			char r, d;
514			const char f[3]; / max expansions + 1 for NULL */
515			va_list ap;
516
517			va_start(ap, fmt);
518			for (n = 0; n < ((sizeof (f)/sizeof (f[0])) - 1); n++) {
519			f[n] = (const char )va_arg(ap, const char );
520			if (f[n] == NULL) {
521			break;
522			}
523			}
524			va_end(ap);
525			f[n] = NULL; /* terminate list */
526
527			len = strlen(fmt) + 1;
528			for (n = 0; f[n] != NULL; n++) {
529			len += strlen(f[n]); /* technically could -2 for "%s" */
530			}
531			r = ecalloc(len, sizeof (char));
532
533			for (n = 0, d = r; *fmt != 0; ) {
534			if (*fmt != '%') {
535			d++ = fmt++;
536			continue;
537			}
538			fmt++;
539			/* Permit embedded "%%" */
540			switch (*fmt) {
541			case '%':
542			*d++ = '%';
543			fmt++;
544			break;
545			case 's':
546			if (f[n] == NULL) {
547			va_end(ap);
548			free(r);
549			return (NULL);
550			}
551			(void) strlcpy(d, f[n++], r + len - d);
552			fmt++;
553			d += strlen(d);
554			break;
555			default:
556			va_end(ap);
557			free(r);
558			return (NULL);
559			}
560			}
561			*d = '\0';
562			return (r);
563			}
564
565			/*
566			* See if we should open a "replacement file"
567			* instead of the file we're about to open.
568			*/
569			char *
570			open_altfile(char filename, int pf, void **pfd)
571			{
572			char *lessopen;
573			char *cmd;
574			FILE *fd;
575			int returnfd = 0;
576
577	✗✓	16	if (!use_lessopen \|\| secure)
578			return (NULL);
579		8	ch_ungetchar(-1);
580	✓✗	8	if ((lessopen = lgetenv("LESSOPEN")) == NULL)
581		8	return (NULL);
582			while (*lessopen == '\|') {
583			/*
584			* If LESSOPEN starts with a \|, it indicates
585			* a "pipe preprocessor".
586			*/
587			lessopen++;
588			returnfd++;
589			}
590			if (*lessopen == '-') {
591			/*
592			* Lessopen preprocessor will accept "-" as a filename.
593			*/
594			lessopen++;
595			} else {
596			if (strcmp(filename, "-") == 0)
597			return (NULL);
598			}
599
600			if ((cmd = expand_pct_s(lessopen, filename, NULL)) == NULL) {
601			error("Invalid LESSOPEN variable", NULL);
602			return (NULL);
603			}
604			fd = shellcmd(cmd);
605			free(cmd);
606			if (fd == NULL) {
607			/*
608			* Cannot create the pipe.
609			*/
610			return (NULL);
611			}
612			if (returnfd) {
613			int f;
614			char c;
615
616			/*
617			* Read one char to see if the pipe will produce any data.
618			* If it does, push the char back on the pipe.
619			*/
620			f = fileno(fd);
621			if (read(f, &c, 1) != 1) {
622			/*
623			* Pipe is empty.
624			* If more than 1 pipe char was specified,
625			* the exit status tells whether the file itself
626			* is empty, or if there is no alt file.
627			* If only one pipe char, just assume no alt file.
628			*/
629			int status = pclose(fd);
630			if (returnfd > 1 && status == 0) {
631			*pfd = NULL;
632			*pf = -1;
633			return (estrdup(FAKE_EMPTYFILE));
634			}
635			return (NULL);
636			}
637			ch_ungetchar(c);
638			pfd = (void ) fd;
639			*pf = f;
640			return (estrdup("-"));
641			}
642			cmd = readfd(fd);
643			pclose(fd);
644			if (*cmd == '\0')
645			/*
646			* Pipe is empty. This means there is no alt file.
647			*/
648			return (NULL);
649			return (cmd);
650		8	}
651
652			/*
653			* Close a replacement file.
654			*/
655			void
656			close_altfile(char altfilename, char filename, void *pipefd)
657			{
658			char *lessclose;
659			FILE *fd;
660			char *cmd;
661
662			if (secure)
663			return;
664			if (pipefd != NULL) {
665			pclose((FILE *)pipefd);
666			}
667			if ((lessclose = lgetenv("LESSCLOSE")) == NULL)
668			return;
669			cmd = expand_pct_s(lessclose, filename, altfilename, NULL);
670			if (cmd == NULL) {
671			error("Invalid LESSCLOSE variable", NULL);
672			return;
673			}
674			fd = shellcmd(cmd);
675			free(cmd);
676			if (fd != NULL)
677			(void) pclose(fd);
678			}
679
680			/*
681			* Is the specified file a directory?
682			*/
683			int
684			is_dir(char *filename)
685			{
686			int isdir = 0;
687			int r;
688		16	struct stat statbuf;
689
690		8	filename = shell_unquote(filename);
691
692		8	r = stat(filename, &statbuf);
693	✓✗	24	isdir = (r >= 0 && S_ISDIR(statbuf.st_mode));
694		8	free(filename);
695		8	return (isdir);
696		8	}
697
698			/*
699			* Returns NULL if the file can be opened and
700			* is an ordinary file, otherwise an error message
701			* (if it cannot be opened or is a directory, etc.)
702			*/
703			char *
704			bad_file(char *filename)
705			{
706			char *m = NULL;
707
708		16	filename = shell_unquote(filename);
709	✓✗✗✓	16	if (!force_open && is_dir(filename)) {
710			m = easprintf("%s is a directory", filename);
711			} else {
712			int r;
713		8	struct stat statbuf;
714
715		8	r = stat(filename, &statbuf);
716	✗✓	8	if (r < 0) {
717			m = errno_message(filename);
718	✗✓	8	} else if (force_open) {
719			m = NULL;
720	✗✓	8	} else if (!S_ISREG(statbuf.st_mode)) {
721			m = easprintf("%s is not a regular file (use -f to "
722			"see it)", filename);
723			}
724		8	}
725		8	free(filename);
726		8	return (m);
727			}
728
729			/*
730			* Return the size of a file, as cheaply as possible.
731			*/
732			off_t
733			filesize(int f)
734			{
735		16	struct stat statbuf;
736
737	✓✗	8	if (fstat(f, &statbuf) >= 0)
738		8	return (statbuf.st_size);
739			return (-1);
740		8	}
741
742			/*
743			* Return last component of a pathname.
744			*/
745			char *
746			last_component(char *name)
747			{
748			char *slash;
749
750			for (slash = name + strlen(name); slash > name; ) {
751			--slash;
752			if (*slash == '/')
753			return (slash + 1);
754			}
755			return (name);
756			}