Ported "grep" from NetBSD to toolbox.

Bug: 6798417
Change-Id: I581c496a726a4814edaaa3672849c090bac8552c

1 files changed, 269 insertions, 0 deletions

diff --git a/toolbox/grep/file.c b/toolbox/grep/file.c
new file mode 100644
index 0000000..86b7658
--- /dev/null
+++ b/toolbox/grep/file.c
@@ -0,0 +1,269 @@
+/*	$NetBSD: file.c,v 1.7 2011/04/18 22:46:48 joerg Exp $	*/
+/*	$FreeBSD: head/usr.bin/grep/file.c 211496 2010-08-19 09:28:59Z des $	*/
+/*	$OpenBSD: file.c,v 1.11 2010/07/02 20:48:48 nicm Exp $	*/
+
+/*-
+ * Copyright (c) 1999 James Howard and Dag-Erling Coïdan Smørgrav
+ * Copyright (C) 2008-2010 Gabor Kovesdan <gabor@FreeBSD.org>
+ * Copyright (C) 2010 Dimitry Andric <dimitry@andric.com>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#if HAVE_NBTOOL_CONFIG_H
+#include "nbtool_config.h"
+#endif
+
+#include <sys/cdefs.h>
+__RCSID("$NetBSD: file.c,v 1.7 2011/04/18 22:46:48 joerg Exp $");
+
+#include <sys/param.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+
+#ifndef ANDROID
+#include <bzlib.h>
+#endif
+#include <err.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <stddef.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <wchar.h>
+#include <wctype.h>
+#ifndef ANDROID
+#include <zlib.h>
+#endif
+
+#include "grep.h"
+
+#define	MAXBUFSIZ	(32 * 1024)
+#define	LNBUFBUMP	80
+
+#ifndef ANDROID
+static gzFile gzbufdesc;
+static BZFILE* bzbufdesc;
+#endif
+
+static unsigned char buffer[MAXBUFSIZ];
+static unsigned char *bufpos;
+static size_t bufrem;
+
+static unsigned char *lnbuf;
+static size_t lnbuflen;
+
+static inline int
+grep_refill(struct file *f)
+{
+	ssize_t nr;
+	int bzerr;
+
+	bufpos = buffer;
+	bufrem = 0;
+
+#ifndef ANDROID
+	if (filebehave == FILE_GZIP)
+		nr = gzread(gzbufdesc, buffer, MAXBUFSIZ);
+	else if (filebehave == FILE_BZIP && bzbufdesc != NULL) {
+		nr = BZ2_bzRead(&bzerr, bzbufdesc, buffer, MAXBUFSIZ);
+		switch (bzerr) {
+		case BZ_OK:
+		case BZ_STREAM_END:
+			/* No problem, nr will be okay */
+			break;
+		case BZ_DATA_ERROR_MAGIC:
+			/*
+			 * As opposed to gzread(), which simply returns the
+			 * plain file data, if it is not in the correct
+			 * compressed format, BZ2_bzRead() instead aborts.
+			 *
+			 * So, just restart at the beginning of the file again,
+			 * and use plain reads from now on.
+			 */
+			BZ2_bzReadClose(&bzerr, bzbufdesc);
+			bzbufdesc = NULL;
+			if (lseek(f->fd, 0, SEEK_SET) == -1)
+				return (-1);
+			nr = read(f->fd, buffer, MAXBUFSIZ);
+			break;
+		default:
+			/* Make sure we exit with an error */
+			nr = -1;
+		}
+	} else
+#endif
+		nr = read(f->fd, buffer, MAXBUFSIZ);
+
+	if (nr < 0)
+		return (-1);
+
+	bufrem = nr;
+	return (0);
+}
+
+static inline int
+grep_lnbufgrow(size_t newlen)
+{
+
+	if (lnbuflen < newlen) {
+		lnbuf = grep_realloc(lnbuf, newlen);
+		lnbuflen = newlen;
+	}
+
+	return (0);
+}
+
+char *
+grep_fgetln(struct file *f, size_t *lenp)
+{
+	unsigned char *p;
+	char *ret;
+	size_t len;
+	size_t off;
+	ptrdiff_t diff;
+
+	/* Fill the buffer, if necessary */
+	if (bufrem == 0 && grep_refill(f) != 0)
+		goto error;
+
+	if (bufrem == 0) {
+		/* Return zero length to indicate EOF */
+		*lenp = 0;
+		return ((char *)bufpos);
+	}
+
+	/* Look for a newline in the remaining part of the buffer */
+	if ((p = memchr(bufpos, line_sep, bufrem)) != NULL) {
+		++p; /* advance over newline */
+		ret = (char *)bufpos;
+		len = p - bufpos;
+		bufrem -= len;
+		bufpos = p;
+		*lenp = len;
+		return (ret);
+	}
+
+	/* We have to copy the current buffered data to the line buffer */
+	for (len = bufrem, off = 0; ; len += bufrem) {
+		/* Make sure there is room for more data */
+		if (grep_lnbufgrow(len + LNBUFBUMP))
+			goto error;
+		memcpy(lnbuf + off, bufpos, len - off);
+		off = len;
+		if (grep_refill(f) != 0)
+			goto error;
+		if (bufrem == 0)
+			/* EOF: return partial line */
+			break;
+		if ((p = memchr(bufpos, line_sep, bufrem)) == NULL)
+			continue;
+		/* got it: finish up the line (like code above) */
+		++p;
+		diff = p - bufpos;
+		len += diff;
+		if (grep_lnbufgrow(len))
+		    goto error;
+		memcpy(lnbuf + off, bufpos, diff);
+		bufrem -= diff;
+		bufpos = p;
+		break;
+	}
+	*lenp = len;
+	return ((char *)lnbuf);
+
+error:
+	*lenp = 0;
+	return (NULL);
+}
+
+static inline struct file *
+grep_file_init(struct file *f)
+{
+
+#ifndef ANDROID
+	if (filebehave == FILE_GZIP &&
+	    (gzbufdesc = gzdopen(f->fd, "r")) == NULL)
+		goto error;
+
+	if (filebehave == FILE_BZIP &&
+	    (bzbufdesc = BZ2_bzdopen(f->fd, "r")) == NULL)
+		goto error;
+#endif
+
+	/* Fill read buffer, also catches errors early */
+	if (grep_refill(f) != 0)
+		goto error;
+
+	/* Check for binary stuff, if necessary */
+	if (!nulldataflag && binbehave != BINFILE_TEXT &&
+	    memchr(bufpos, '\0', bufrem) != NULL)
+		f->binary = true;
+
+	return (f);
+error:
+	close(f->fd);
+	free(f);
+	return (NULL);
+}
+
+/*
+ * Opens a file for processing.
+ */
+struct file *
+grep_open(const char *path)
+{
+	struct file *f;
+
+	f = grep_malloc(sizeof *f);
+	memset(f, 0, sizeof *f);
+	if (path == NULL) {
+		/* Processing stdin implies --line-buffered. */
+		lbflag = true;
+		f->fd = STDIN_FILENO;
+	} else if ((f->fd = open(path, O_RDONLY)) == -1) {
+		free(f);
+		return (NULL);
+	}
+
+	return (grep_file_init(f));
+}
+
+/*
+ * Closes a file.
+ */
+void
+grep_close(struct file *f)
+{
+
+	close(f->fd);
+
+	/* Reset read buffer and line buffer */
+	bufpos = buffer;
+	bufrem = 0;
+
+	free(lnbuf);
+	lnbuf = NULL;
+	lnbuflen = 0;
+}