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authorAndreas Baumann <mail@andreasbaumann.cc>2015-01-03 12:04:58 +0100
committerAndreas Baumann <mail@andreasbaumann.cc>2015-01-03 12:04:58 +0100
commit008d0be72b2f160382c6e880765e96b64a050c65 (patch)
tree36f48a98a3815a408e2ce1693dd182af90f80305 /release/src/router/busybox/coreutils/tail.c
parent611becfb8726c60cb060368541ad98191d4532f5 (diff)
downloadtomato-008d0be72b2f160382c6e880765e96b64a050c65.tar.gz
tomato-008d0be72b2f160382c6e880765e96b64a050c65.tar.bz2
imported original firmware WRT54GL_v4.30.11_11_US
Diffstat (limited to 'release/src/router/busybox/coreutils/tail.c')
-rw-r--r--release/src/router/busybox/coreutils/tail.c339
1 files changed, 339 insertions, 0 deletions
diff --git a/release/src/router/busybox/coreutils/tail.c b/release/src/router/busybox/coreutils/tail.c
new file mode 100644
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--- /dev/null
+++ b/release/src/router/busybox/coreutils/tail.c
@@ -0,0 +1,339 @@
+/* vi: set sw=4 ts=4: */
+/*
+ * Mini tail implementation for busybox
+ *
+ * Copyright (C) 2001 by Matt Kraai <kraai@alumni.carnegiemellon.edu>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ *
+ */
+
+/* BB_AUDIT SUSv3 compliant (need fancy for -c) */
+/* BB_AUDIT GNU compatible -c, -q, and -v options in 'fancy' configuration. */
+/* http://www.opengroup.org/onlinepubs/007904975/utilities/tail.html */
+
+/* Mar 16, 2003 Manuel Novoa III (mjn3@codepoet.org)
+ *
+ * Pretty much rewritten to fix numerous bugs and reduce realloc() calls.
+ * Bugs fixed (although I may have forgotten one or two... it was pretty bad)
+ * 1) mixing printf/write without fflush()ing stdout
+ * 2) no check that any open files are present
+ * 3) optstring had -q taking an arg
+ * 4) no error checking on write in some cases, and a warning even then
+ * 5) q and s interaction bug
+ * 6) no check for lseek error
+ * 7) lseek attempted when count==0 even if arg was +0 (from top)
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <ctype.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <sys/stat.h>
+#include "busybox.h"
+
+static const struct suffix_mult tail_suffixes[] = {
+ { "b", 512 },
+ { "k", 1024 },
+ { "m", 1048576 },
+ { NULL, 0 }
+};
+
+static int status
+#if EXIT_SUCCESS != 0
+ = EXIT_SUCCESS /* If it is 0 (paranoid check), let bss initialize it. */
+#endif
+ ;
+
+static void tail_xprint_header(const char *fmt, const char *filename)
+{
+ /* If we get an output error, there is really no sense in continuing. */
+ if (dprintf(STDOUT_FILENO, fmt, filename) < 0) {
+ bb_perror_nomsg_and_die();
+ }
+}
+
+/* len should probably be size_t */
+static void tail_xbb_full_write(const char *buf, size_t len)
+{
+ /* If we get a write error, there is really no sense in continuing. */
+ if (bb_full_write(STDOUT_FILENO, buf, len) < 0) {
+ bb_perror_nomsg_and_die();
+ }
+}
+
+static ssize_t tail_read(int fd, char *buf, size_t count)
+{
+ ssize_t r;
+
+ if ((r = safe_read(fd, buf, count)) < 0) {
+ bb_perror_msg("read");
+ status = EXIT_FAILURE;
+ }
+
+ return r;
+}
+
+static const char tail_opts[] =
+ "fn:"
+#ifdef CONFIG_FEATURE_FANCY_TAIL
+ "c:qs:v"
+#endif
+ ;
+
+static const char header_fmt[] = "\n==> %s <==\n";
+
+int tail_main(int argc, char **argv)
+{
+ long count = 10;
+ unsigned int sleep_period = 1;
+ int from_top = 0;
+ int follow = 0;
+ int header_threshhold = 1;
+#ifdef CONFIG_FEATURE_FANCY_TAIL
+ int count_bytes = 0;
+#endif
+
+ char *tailbuf;
+ size_t tailbufsize;
+ int taillen = 0;
+ int newline = 0;
+
+ int *fds, nfiles, nread, nwrite, seen, i, opt;
+ char *s, *buf;
+ const char *fmt;
+
+ /* Allow legacy syntax of an initial numeric option without -n. */
+ if (argc >=2 && ((argv[1][0] == '+') || ((argv[1][0] == '-')
+ /* && (isdigit)(argv[1][1]) */
+ && (((unsigned int)(argv[1][1] - '0')) <= 9))))
+ {
+ optind = 2;
+ optarg = argv[1];
+ goto GET_COUNT;
+ }
+
+ while ((opt = getopt(argc, argv, tail_opts)) > 0) {
+ switch (opt) {
+ case 'f':
+ follow = 1;
+ break;
+#ifdef CONFIG_FEATURE_FANCY_TAIL
+ case 'c':
+ count_bytes = 1;
+ /* FALLS THROUGH */
+#endif
+ case 'n':
+ GET_COUNT:
+ count = bb_xgetlarg10_sfx(optarg, tail_suffixes);
+ /* Note: Leading whitespace is an error trapped above. */
+ if (*optarg == '+') {
+ from_top = 1;
+ } else {
+ from_top = 0;
+ }
+ if (count < 0) {
+ count = -count;
+ }
+ break;
+#ifdef CONFIG_FEATURE_FANCY_TAIL
+ case 'q':
+ header_threshhold = INT_MAX;
+ break;
+ case 's':
+ sleep_period =bb_xgetularg10_bnd(optarg, 0, UINT_MAX);
+ break;
+ case 'v':
+ header_threshhold = 0;
+ break;
+#endif
+ default:
+ bb_show_usage();
+ }
+ }
+
+ /* open all the files */
+ fds = (int *)xmalloc(sizeof(int) * (argc - optind + 1));
+
+ argv += optind;
+ nfiles = i = 0;
+
+ if ((argc -= optind) == 0) {
+ struct stat statbuf;
+
+ if (!fstat(STDIN_FILENO, &statbuf) && S_ISFIFO(statbuf.st_mode)) {
+ follow = 0;
+ }
+ /* --argv; */
+ *argv = (char *) bb_msg_standard_input;
+ goto DO_STDIN;
+ }
+
+ do {
+ if ((argv[i][0] == '-') && !argv[i][1]) {
+ DO_STDIN:
+ fds[nfiles] = STDIN_FILENO;
+ } else if ((fds[nfiles] = open(argv[i], O_RDONLY)) < 0) {
+ bb_perror_msg("%s", argv[i]);
+ status = EXIT_FAILURE;
+ continue;
+ }
+ argv[nfiles] = argv[i];
+ ++nfiles;
+ } while (++i < argc);
+
+ if (!nfiles) {
+ bb_error_msg_and_die("no files");
+ }
+
+ tailbufsize = BUFSIZ;
+#ifdef CONFIG_FEATURE_FANCY_TAIL
+ /* tail the files */
+ if (from_top < count_bytes) { /* Each is 0 or 1, so true iff 0 < 1. */
+ /* Hence, !from_top && count_bytes */
+ if (tailbufsize < count) {
+ tailbufsize = count + BUFSIZ;
+ }
+ }
+#endif
+ buf = tailbuf = xmalloc(tailbufsize);
+
+ fmt = header_fmt + 1; /* Skip header leading newline on first output. */
+ i = 0;
+ do {
+ /* Be careful. It would be possible to optimize the count-bytes
+ * case if the file is seekable. If you do though, remember that
+ * starting file position may not be the beginning of the file.
+ * Beware of backing up too far. See example in wc.c.
+ */
+ if ((!(count|from_top)) && (lseek(fds[i], 0, SEEK_END) >= 0)) {
+ continue;
+ }
+
+ if (nfiles > header_threshhold) {
+ tail_xprint_header(fmt, argv[i]);
+ fmt = header_fmt;
+ }
+
+ buf = tailbuf;
+ taillen = 0;
+ seen = 1;
+
+ while ((nread = tail_read(fds[i], buf, tailbufsize-taillen)) > 0) {
+ if (from_top) {
+ nwrite = nread;
+ if (seen < count) {
+#ifdef CONFIG_FEATURE_FANCY_TAIL
+ if (count_bytes) {
+ nwrite -= (count - seen);
+ seen = count;
+ } else
+#endif
+ {
+ s = buf;
+ do {
+ --nwrite;
+ if ((*s++ == '\n') && (++seen == count)) {
+ break;
+ }
+ } while (nwrite);
+ }
+ }
+ tail_xbb_full_write(buf + nread - nwrite, nwrite);
+ } else if (count) {
+#ifdef CONFIG_FEATURE_FANCY_TAIL
+ if (count_bytes) {
+ taillen += nread;
+ if (taillen > count) {
+ memmove(tailbuf, tailbuf + taillen - count, count);
+ taillen = count;
+ }
+ } else
+#endif
+ {
+ int k = nread;
+ int nbuf = 0;
+
+ while (k) {
+ --k;
+ if (buf[k] == '\n') {
+ ++nbuf;
+ }
+ }
+
+ if (newline + nbuf < count) {
+ newline += nbuf;
+ taillen += nread;
+
+ } else {
+ int extra = 0;
+ if (buf[nread-1] != '\n') {
+ extra = 1;
+ }
+
+ k = newline + nbuf + extra - count;
+ s = tailbuf;
+ while (k) {
+ if (*s == '\n') {
+ --k;
+ }
+ ++s;
+ }
+
+ taillen += nread - (s - tailbuf);
+ memmove(tailbuf, s, taillen);
+ newline = count - extra;
+ }
+ if (tailbufsize < taillen + BUFSIZ) {
+ tailbufsize = taillen + BUFSIZ;
+ tailbuf = xrealloc(tailbuf, tailbufsize);
+ }
+ }
+ buf = tailbuf + taillen;
+ }
+ }
+
+ if (!from_top) {
+ tail_xbb_full_write(tailbuf, taillen);
+ }
+
+ taillen = 0;
+ } while (++i < nfiles);
+
+ buf = xrealloc(tailbuf, BUFSIZ);
+
+ fmt = NULL;
+
+ while (follow) {
+ sleep(sleep_period);
+ i = 0;
+ do {
+ if (nfiles > header_threshhold) {
+ fmt = header_fmt;
+ }
+ while ((nread = tail_read(fds[i], buf, sizeof(buf))) > 0) {
+ if (fmt) {
+ tail_xprint_header(fmt, argv[i]);
+ fmt = NULL;
+ }
+ tail_xbb_full_write(buf, nread);
+ }
+ } while (++i < nfiles);
+ }
+
+ return status;
+}