Ported "grep" from NetBSD to toolbox.
Bug: 6798417
Change-Id: I581c496a726a4814edaaa3672849c090bac8552c
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;
+}