• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
1 /*	$NetBSD: file.c,v 1.7 2011/04/18 22:46:48 joerg Exp $	*/
2 /*	$FreeBSD: head/usr.bin/grep/file.c 211496 2010-08-19 09:28:59Z des $	*/
3 /*	$OpenBSD: file.c,v 1.11 2010/07/02 20:48:48 nicm Exp $	*/
4 
5 /*-
6  * Copyright (c) 1999 James Howard and Dag-Erling Coïdan Smørgrav
7  * Copyright (C) 2008-2010 Gabor Kovesdan <gabor@FreeBSD.org>
8  * Copyright (C) 2010 Dimitry Andric <dimitry@andric.com>
9  * All rights reserved.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions and the following disclaimer.
16  * 2. Redistributions in binary form must reproduce the above copyright
17  *    notice, this list of conditions and the following disclaimer in the
18  *    documentation and/or other materials provided with the distribution.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30  * SUCH DAMAGE.
31  */
32 
33 #if HAVE_NBTOOL_CONFIG_H
34 #include "nbtool_config.h"
35 #endif
36 
37 #include <sys/cdefs.h>
38 __RCSID("$NetBSD: file.c,v 1.7 2011/04/18 22:46:48 joerg Exp $");
39 
40 #include <sys/param.h>
41 #include <sys/types.h>
42 #include <sys/stat.h>
43 
44 #ifndef ANDROID
45 #include <bzlib.h>
46 #endif
47 #include <err.h>
48 #include <errno.h>
49 #include <fcntl.h>
50 #include <stddef.h>
51 #include <stdlib.h>
52 #include <string.h>
53 #include <unistd.h>
54 #include <wchar.h>
55 #include <wctype.h>
56 #ifndef ANDROID
57 #include <zlib.h>
58 #endif
59 
60 #include "grep.h"
61 
62 #define	MAXBUFSIZ	(32 * 1024)
63 #define	LNBUFBUMP	80
64 
65 #ifndef ANDROID
66 static gzFile gzbufdesc;
67 static BZFILE* bzbufdesc;
68 #endif
69 
70 static unsigned char buffer[MAXBUFSIZ];
71 static unsigned char *bufpos;
72 static size_t bufrem;
73 
74 static unsigned char *lnbuf;
75 static size_t lnbuflen;
76 
77 static inline int
grep_refill(struct file * f)78 grep_refill(struct file *f)
79 {
80 	ssize_t nr;
81 	int bzerr;
82 
83 	bufpos = buffer;
84 	bufrem = 0;
85 
86 #ifndef ANDROID
87 	if (filebehave == FILE_GZIP)
88 		nr = gzread(gzbufdesc, buffer, MAXBUFSIZ);
89 	else if (filebehave == FILE_BZIP && bzbufdesc != NULL) {
90 		nr = BZ2_bzRead(&bzerr, bzbufdesc, buffer, MAXBUFSIZ);
91 		switch (bzerr) {
92 		case BZ_OK:
93 		case BZ_STREAM_END:
94 			/* No problem, nr will be okay */
95 			break;
96 		case BZ_DATA_ERROR_MAGIC:
97 			/*
98 			 * As opposed to gzread(), which simply returns the
99 			 * plain file data, if it is not in the correct
100 			 * compressed format, BZ2_bzRead() instead aborts.
101 			 *
102 			 * So, just restart at the beginning of the file again,
103 			 * and use plain reads from now on.
104 			 */
105 			BZ2_bzReadClose(&bzerr, bzbufdesc);
106 			bzbufdesc = NULL;
107 			if (lseek(f->fd, 0, SEEK_SET) == -1)
108 				return (-1);
109 			nr = read(f->fd, buffer, MAXBUFSIZ);
110 			break;
111 		default:
112 			/* Make sure we exit with an error */
113 			nr = -1;
114 		}
115 	} else
116 #endif
117 		nr = read(f->fd, buffer, MAXBUFSIZ);
118 
119 	if (nr < 0)
120 		return (-1);
121 
122 	bufrem = nr;
123 	return (0);
124 }
125 
126 static inline int
grep_lnbufgrow(size_t newlen)127 grep_lnbufgrow(size_t newlen)
128 {
129 
130 	if (lnbuflen < newlen) {
131 		lnbuf = grep_realloc(lnbuf, newlen);
132 		lnbuflen = newlen;
133 	}
134 
135 	return (0);
136 }
137 
138 char *
grep_fgetln(struct file * f,size_t * lenp)139 grep_fgetln(struct file *f, size_t *lenp)
140 {
141 	unsigned char *p;
142 	char *ret;
143 	size_t len;
144 	size_t off;
145 	ptrdiff_t diff;
146 
147 	/* Fill the buffer, if necessary */
148 	if (bufrem == 0 && grep_refill(f) != 0)
149 		goto error;
150 
151 	if (bufrem == 0) {
152 		/* Return zero length to indicate EOF */
153 		*lenp = 0;
154 		return ((char *)bufpos);
155 	}
156 
157 	/* Look for a newline in the remaining part of the buffer */
158 	if ((p = memchr(bufpos, line_sep, bufrem)) != NULL) {
159 		++p; /* advance over newline */
160 		ret = (char *)bufpos;
161 		len = p - bufpos;
162 		bufrem -= len;
163 		bufpos = p;
164 		*lenp = len;
165 		return (ret);
166 	}
167 
168 	/* We have to copy the current buffered data to the line buffer */
169 	for (len = bufrem, off = 0; ; len += bufrem) {
170 		/* Make sure there is room for more data */
171 		if (grep_lnbufgrow(len + LNBUFBUMP))
172 			goto error;
173 		memcpy(lnbuf + off, bufpos, len - off);
174 		off = len;
175 		if (grep_refill(f) != 0)
176 			goto error;
177 		if (bufrem == 0)
178 			/* EOF: return partial line */
179 			break;
180 		if ((p = memchr(bufpos, line_sep, bufrem)) == NULL)
181 			continue;
182 		/* got it: finish up the line (like code above) */
183 		++p;
184 		diff = p - bufpos;
185 		len += diff;
186 		if (grep_lnbufgrow(len))
187 		    goto error;
188 		memcpy(lnbuf + off, bufpos, diff);
189 		bufrem -= diff;
190 		bufpos = p;
191 		break;
192 	}
193 	*lenp = len;
194 	return ((char *)lnbuf);
195 
196 error:
197 	*lenp = 0;
198 	return (NULL);
199 }
200 
201 static inline struct file *
grep_file_init(struct file * f)202 grep_file_init(struct file *f)
203 {
204 
205 #ifndef ANDROID
206 	if (filebehave == FILE_GZIP &&
207 	    (gzbufdesc = gzdopen(f->fd, "r")) == NULL)
208 		goto error;
209 
210 	if (filebehave == FILE_BZIP &&
211 	    (bzbufdesc = BZ2_bzdopen(f->fd, "r")) == NULL)
212 		goto error;
213 #endif
214 
215 	/* Fill read buffer, also catches errors early */
216 	if (grep_refill(f) != 0)
217 		goto error;
218 
219 	/* Check for binary stuff, if necessary */
220 	if (!nulldataflag && binbehave != BINFILE_TEXT &&
221 	    memchr(bufpos, '\0', bufrem) != NULL)
222 		f->binary = true;
223 
224 	return (f);
225 error:
226 	close(f->fd);
227 	free(f);
228 	return (NULL);
229 }
230 
231 /*
232  * Opens a file for processing.
233  */
234 struct file *
grep_open(const char * path)235 grep_open(const char *path)
236 {
237 	struct file *f;
238 
239 	f = grep_malloc(sizeof *f);
240 	memset(f, 0, sizeof *f);
241 	if (path == NULL) {
242 		/* Processing stdin implies --line-buffered. */
243 		lbflag = true;
244 		f->fd = STDIN_FILENO;
245 	} else if ((f->fd = open(path, O_RDONLY)) == -1) {
246 		free(f);
247 		return (NULL);
248 	}
249 
250 	return (grep_file_init(f));
251 }
252 
253 /*
254  * Closes a file.
255  */
256 void
grep_close(struct file * f)257 grep_close(struct file *f)
258 {
259 
260 	close(f->fd);
261 
262 	/* Reset read buffer and line buffer */
263 	bufpos = buffer;
264 	bufrem = 0;
265 
266 	free(lnbuf);
267 	lnbuf = NULL;
268 	lnbuflen = 0;
269 }
270