Erik Andersen | e49d5ec | 2000-02-08 19:58:47 +0000 | [diff] [blame] | 1 | /* vi: set sw=4 ts=4: */ |
Matt Kraai | 55bccf3 | 2001-01-05 02:57:53 +0000 | [diff] [blame] | 2 | /* |
| 3 | * Mini tail implementation for busybox |
| 4 | * |
Matt Kraai | 55bccf3 | 2001-01-05 02:57:53 +0000 | [diff] [blame] | 5 | * Copyright (C) 2001 by Matt Kraai <kraai@alumni.carnegiemellon.edu> |
| 6 | * |
Rob Landley | f8fd4db | 2006-01-30 01:30:39 +0000 | [diff] [blame] | 7 | * Licensed under GPLv2 or later, see file LICENSE in this tarball for details. |
Erik Andersen | 3fe39dc | 2000-01-25 18:13:53 +0000 | [diff] [blame] | 8 | */ |
Matt Kraai | 55bccf3 | 2001-01-05 02:57:53 +0000 | [diff] [blame] | 9 | |
Manuel Novoa III | cad5364 | 2003-03-19 09:13:01 +0000 | [diff] [blame] | 10 | /* BB_AUDIT SUSv3 compliant (need fancy for -c) */ |
| 11 | /* BB_AUDIT GNU compatible -c, -q, and -v options in 'fancy' configuration. */ |
| 12 | /* http://www.opengroup.org/onlinepubs/007904975/utilities/tail.html */ |
Eric Andersen | abc0f4f | 1999-12-08 23:19:36 +0000 | [diff] [blame] | 13 | |
Manuel Novoa III | cad5364 | 2003-03-19 09:13:01 +0000 | [diff] [blame] | 14 | /* Mar 16, 2003 Manuel Novoa III (mjn3@codepoet.org) |
| 15 | * |
| 16 | * Pretty much rewritten to fix numerous bugs and reduce realloc() calls. |
| 17 | * Bugs fixed (although I may have forgotten one or two... it was pretty bad) |
| 18 | * 1) mixing printf/write without fflush()ing stdout |
| 19 | * 2) no check that any open files are present |
| 20 | * 3) optstring had -q taking an arg |
| 21 | * 4) no error checking on write in some cases, and a warning even then |
| 22 | * 5) q and s interaction bug |
| 23 | * 6) no check for lseek error |
| 24 | * 7) lseek attempted when count==0 even if arg was +0 (from top) |
| 25 | */ |
| 26 | |
Denis Vlasenko | b6adbf1 | 2007-05-26 19:00:18 +0000 | [diff] [blame] | 27 | #include "libbb.h" |
Eric Andersen | abc0f4f | 1999-12-08 23:19:36 +0000 | [diff] [blame] | 28 | |
Matt Kraai | a164c64 | 2001-02-05 17:50:03 +0000 | [diff] [blame] | 29 | static const struct suffix_mult tail_suffixes[] = { |
Matt Kraai | 24ac017 | 2000-12-18 21:38:57 +0000 | [diff] [blame] | 30 | { "b", 512 }, |
| 31 | { "k", 1024 }, |
Denis Vlasenko | e31f721 | 2006-12-22 16:06:16 +0000 | [diff] [blame] | 32 | { "m", 1024*1024 }, |
Denis Vlasenko | f868963 | 2007-07-27 15:06:25 +0000 | [diff] [blame] | 33 | { } |
Matt Kraai | 24ac017 | 2000-12-18 21:38:57 +0000 | [diff] [blame] | 34 | }; |
| 35 | |
Bernhard Reutner-Fischer | d9c2d5f | 2007-04-04 20:29:15 +0000 | [diff] [blame] | 36 | struct globals { |
| 37 | bool status; |
| 38 | }; |
| 39 | #define G (*(struct globals*)&bb_common_bufsiz1) |
Matt Kraai | 55bccf3 | 2001-01-05 02:57:53 +0000 | [diff] [blame] | 40 | |
Bernhard Reutner-Fischer | 73561cc | 2006-08-28 23:31:54 +0000 | [diff] [blame] | 41 | static void tail_xprint_header(const char *fmt, const char *filename) |
| 42 | { |
Denis Vlasenko | e31f721 | 2006-12-22 16:06:16 +0000 | [diff] [blame] | 43 | if (fdprintf(STDOUT_FILENO, fmt, filename) < 0) |
Bernhard Reutner-Fischer | 73561cc | 2006-08-28 23:31:54 +0000 | [diff] [blame] | 44 | bb_perror_nomsg_and_die(); |
Bernhard Reutner-Fischer | 73561cc | 2006-08-28 23:31:54 +0000 | [diff] [blame] | 45 | } |
| 46 | |
Manuel Novoa III | cad5364 | 2003-03-19 09:13:01 +0000 | [diff] [blame] | 47 | static ssize_t tail_read(int fd, char *buf, size_t count) |
| 48 | { |
| 49 | ssize_t r; |
Denis Vlasenko | 368a12e | 2007-10-02 10:17:56 +0000 | [diff] [blame] | 50 | off_t current; |
Paul Fox | 4905434 | 2005-07-20 19:46:32 +0000 | [diff] [blame] | 51 | struct stat sbuf; |
Manuel Novoa III | cad5364 | 2003-03-19 09:13:01 +0000 | [diff] [blame] | 52 | |
Denis Vlasenko | 368a12e | 2007-10-02 10:17:56 +0000 | [diff] [blame] | 53 | /* (A good comment is missing here) */ |
| 54 | current = lseek(fd, 0, SEEK_CUR); |
| 55 | /* /proc files report zero st_size, don't lseek them. */ |
| 56 | if (fstat(fd, &sbuf) == 0 && sbuf.st_size) |
| 57 | if (sbuf.st_size < current) |
| 58 | lseek(fd, 0, SEEK_SET); |
| 59 | |
Denis Vlasenko | 226002e | 2007-10-05 19:17:16 +0000 | [diff] [blame] | 60 | r = full_read(fd, buf, count); |
Denis Vlasenko | e31f721 | 2006-12-22 16:06:16 +0000 | [diff] [blame] | 61 | if (r < 0) { |
Bernhard Reutner-Fischer | 1b9d7c9 | 2006-06-03 22:45:37 +0000 | [diff] [blame] | 62 | bb_perror_msg(bb_msg_read_error); |
Bernhard Reutner-Fischer | d9c2d5f | 2007-04-04 20:29:15 +0000 | [diff] [blame] | 63 | G.status = EXIT_FAILURE; |
Manuel Novoa III | cad5364 | 2003-03-19 09:13:01 +0000 | [diff] [blame] | 64 | } |
| 65 | |
| 66 | return r; |
| 67 | } |
| 68 | |
Denis Vlasenko | 6ca409e | 2007-08-12 20:58:27 +0000 | [diff] [blame] | 69 | static const char header_fmt[] ALIGN1 = "\n==> %s <==\n"; |
Manuel Novoa III | cad5364 | 2003-03-19 09:13:01 +0000 | [diff] [blame] | 70 | |
Denis Vlasenko | ac678ec | 2007-04-16 22:32:04 +0000 | [diff] [blame] | 71 | static unsigned eat_num(const char *p) |
| 72 | { |
Denis Vlasenko | 368a12e | 2007-10-02 10:17:56 +0000 | [diff] [blame] | 73 | if (*p == '-') |
| 74 | p++; |
| 75 | else if (*p == '+') { |
| 76 | p++; |
Denis Vlasenko | e8419c9 | 2008-02-19 00:38:10 +0000 | [diff] [blame] | 77 | G.status = 1; /* mark that we saw "+" */ |
Denis Vlasenko | 368a12e | 2007-10-02 10:17:56 +0000 | [diff] [blame] | 78 | } |
Bernhard Reutner-Fischer | 84d2d49 | 2007-01-24 21:38:10 +0000 | [diff] [blame] | 79 | return xatou_sfx(p, tail_suffixes); |
| 80 | } |
| 81 | |
Denis Vlasenko | 9b49a5e | 2007-10-11 10:05:36 +0000 | [diff] [blame] | 82 | int tail_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE; |
Eric Andersen | 98bbd68 | 2000-07-31 17:05:58 +0000 | [diff] [blame] | 83 | int tail_main(int argc, char **argv) |
Eric Andersen | abc0f4f | 1999-12-08 23:19:36 +0000 | [diff] [blame] | 84 | { |
Denis Vlasenko | e31f721 | 2006-12-22 16:06:16 +0000 | [diff] [blame] | 85 | unsigned count = 10; |
Denis Vlasenko | 459903b | 2006-11-27 14:44:18 +0000 | [diff] [blame] | 86 | unsigned sleep_period = 1; |
Bernhard Reutner-Fischer | 84d2d49 | 2007-01-24 21:38:10 +0000 | [diff] [blame] | 87 | bool from_top; |
Manuel Novoa III | cad5364 | 2003-03-19 09:13:01 +0000 | [diff] [blame] | 88 | int header_threshhold = 1; |
Denis Vlasenko | 92c0b82 | 2007-05-08 17:27:17 +0000 | [diff] [blame] | 89 | const char *str_c, *str_n; |
Eric Andersen | abc0f4f | 1999-12-08 23:19:36 +0000 | [diff] [blame] | 90 | |
Manuel Novoa III | cad5364 | 2003-03-19 09:13:01 +0000 | [diff] [blame] | 91 | char *tailbuf; |
| 92 | size_t tailbufsize; |
| 93 | int taillen = 0; |
Denis Vlasenko | e8419c9 | 2008-02-19 00:38:10 +0000 | [diff] [blame] | 94 | int newlines_seen = 0; |
Denis Vlasenko | 77ad97f | 2008-05-13 02:27:31 +0000 | [diff] [blame] | 95 | int nfiles, nread, nwrite, i, opt; |
| 96 | unsigned seen; |
Manuel Novoa III | cad5364 | 2003-03-19 09:13:01 +0000 | [diff] [blame] | 97 | |
Denis Vlasenko | e31f721 | 2006-12-22 16:06:16 +0000 | [diff] [blame] | 98 | int *fds; |
Manuel Novoa III | cad5364 | 2003-03-19 09:13:01 +0000 | [diff] [blame] | 99 | char *s, *buf; |
| 100 | const char *fmt; |
| 101 | |
Denis Vlasenko | 0849207 | 2006-12-22 13:56:36 +0000 | [diff] [blame] | 102 | #if ENABLE_INCLUDE_SUSv2 || ENABLE_FEATURE_FANCY_TAIL |
Manuel Novoa III | cad5364 | 2003-03-19 09:13:01 +0000 | [diff] [blame] | 103 | /* Allow legacy syntax of an initial numeric option without -n. */ |
Denis Vlasenko | 62a90cd | 2008-03-17 09:07:36 +0000 | [diff] [blame] | 104 | if (argv[1] && (argv[1][0] == '+' || argv[1][0] == '-') |
Denis Vlasenko | 459903b | 2006-11-27 14:44:18 +0000 | [diff] [blame] | 105 | && isdigit(argv[1][1]) |
| 106 | ) { |
Denis Vlasenko | 3603cd2 | 2009-03-27 02:36:02 +0000 | [diff] [blame] | 107 | count = eat_num(argv[1]); |
Denis Vlasenko | 62a90cd | 2008-03-17 09:07:36 +0000 | [diff] [blame] | 108 | argv++; |
| 109 | argc--; |
Robert Griebl | 13c26fc | 2002-05-17 22:18:04 +0000 | [diff] [blame] | 110 | } |
Glenn L McGrath | 0bd0257 | 2005-12-11 03:09:05 +0000 | [diff] [blame] | 111 | #endif |
Robert Griebl | 13c26fc | 2002-05-17 22:18:04 +0000 | [diff] [blame] | 112 | |
Denis Vlasenko | 5e34ff2 | 2009-04-21 11:09:40 +0000 | [diff] [blame^] | 113 | IF_FEATURE_FANCY_TAIL(opt_complementary = "s+";) /* -s N */ |
| 114 | opt = getopt32(argv, "fc:n:" IF_FEATURE_FANCY_TAIL("qs:v"), |
| 115 | &str_c, &str_n IF_FEATURE_FANCY_TAIL(,&sleep_period)); |
Denis Vlasenko | e31f721 | 2006-12-22 16:06:16 +0000 | [diff] [blame] | 116 | #define FOLLOW (opt & 0x1) |
| 117 | #define COUNT_BYTES (opt & 0x2) |
| 118 | //if (opt & 0x1) // -f |
Bernhard Reutner-Fischer | 84d2d49 | 2007-01-24 21:38:10 +0000 | [diff] [blame] | 119 | if (opt & 0x2) count = eat_num(str_c); // -c |
| 120 | if (opt & 0x4) count = eat_num(str_n); // -n |
Bernhard Reutner-Fischer | 5816ccb | 2005-12-13 10:48:45 +0000 | [diff] [blame] | 121 | #if ENABLE_FEATURE_FANCY_TAIL |
Denis Vlasenko | e31f721 | 2006-12-22 16:06:16 +0000 | [diff] [blame] | 122 | if (opt & 0x8) header_threshhold = INT_MAX; // -q |
Denis Vlasenko | e31f721 | 2006-12-22 16:06:16 +0000 | [diff] [blame] | 123 | if (opt & 0x20) header_threshhold = 0; // -v |
Matt Kraai | 55bccf3 | 2001-01-05 02:57:53 +0000 | [diff] [blame] | 124 | #endif |
Denis Vlasenko | 6910741 | 2006-12-21 00:43:06 +0000 | [diff] [blame] | 125 | argc -= optind; |
| 126 | argv += optind; |
Denis Vlasenko | e8419c9 | 2008-02-19 00:38:10 +0000 | [diff] [blame] | 127 | from_top = G.status; /* 1 if there was "-c +N" or "-n +N" */ |
| 128 | G.status = EXIT_SUCCESS; |
Matt Kraai | 55bccf3 | 2001-01-05 02:57:53 +0000 | [diff] [blame] | 129 | |
| 130 | /* open all the files */ |
Denis Vlasenko | 6910741 | 2006-12-21 00:43:06 +0000 | [diff] [blame] | 131 | fds = xmalloc(sizeof(int) * (argc + 1)); |
Denis Vlasenko | 62a90cd | 2008-03-17 09:07:36 +0000 | [diff] [blame] | 132 | if (!argv[0]) { |
Manuel Novoa III | cad5364 | 2003-03-19 09:13:01 +0000 | [diff] [blame] | 133 | struct stat statbuf; |
| 134 | |
| 135 | if (!fstat(STDIN_FILENO, &statbuf) && S_ISFIFO(statbuf.st_mode)) { |
Denis Vlasenko | e31f721 | 2006-12-22 16:06:16 +0000 | [diff] [blame] | 136 | opt &= ~1; /* clear FOLLOW */ |
Matt Kraai | 55bccf3 | 2001-01-05 02:57:53 +0000 | [diff] [blame] | 137 | } |
Manuel Novoa III | cad5364 | 2003-03-19 09:13:01 +0000 | [diff] [blame] | 138 | *argv = (char *) bb_msg_standard_input; |
Matt Kraai | 55bccf3 | 2001-01-05 02:57:53 +0000 | [diff] [blame] | 139 | } |
Denis Vlasenko | 62a90cd | 2008-03-17 09:07:36 +0000 | [diff] [blame] | 140 | nfiles = i = 0; |
Manuel Novoa III | cad5364 | 2003-03-19 09:13:01 +0000 | [diff] [blame] | 141 | do { |
Denis Vlasenko | 62a90cd | 2008-03-17 09:07:36 +0000 | [diff] [blame] | 142 | int fd = open_or_warn_stdin(argv[i]); |
| 143 | if (fd < 0) { |
Bernhard Reutner-Fischer | d9c2d5f | 2007-04-04 20:29:15 +0000 | [diff] [blame] | 144 | G.status = EXIT_FAILURE; |
| 145 | continue; |
Manuel Novoa III | cad5364 | 2003-03-19 09:13:01 +0000 | [diff] [blame] | 146 | } |
Denis Vlasenko | 62a90cd | 2008-03-17 09:07:36 +0000 | [diff] [blame] | 147 | fds[nfiles] = fd; |
Bernhard Reutner-Fischer | d9c2d5f | 2007-04-04 20:29:15 +0000 | [diff] [blame] | 148 | argv[nfiles++] = argv[i]; |
Manuel Novoa III | cad5364 | 2003-03-19 09:13:01 +0000 | [diff] [blame] | 149 | } while (++i < argc); |
| 150 | |
Denis Vlasenko | e31f721 | 2006-12-22 16:06:16 +0000 | [diff] [blame] | 151 | if (!nfiles) |
Manuel Novoa III | cad5364 | 2003-03-19 09:13:01 +0000 | [diff] [blame] | 152 | bb_error_msg_and_die("no files"); |
Manuel Novoa III | cad5364 | 2003-03-19 09:13:01 +0000 | [diff] [blame] | 153 | |
Denis Vlasenko | e8419c9 | 2008-02-19 00:38:10 +0000 | [diff] [blame] | 154 | /* prepare the buffer */ |
Manuel Novoa III | cad5364 | 2003-03-19 09:13:01 +0000 | [diff] [blame] | 155 | tailbufsize = BUFSIZ; |
Denis Vlasenko | e31f721 | 2006-12-22 16:06:16 +0000 | [diff] [blame] | 156 | if (!from_top && COUNT_BYTES) { |
Denis Vlasenko | e8419c9 | 2008-02-19 00:38:10 +0000 | [diff] [blame] | 157 | if (tailbufsize < count + BUFSIZ) { |
Manuel Novoa III | cad5364 | 2003-03-19 09:13:01 +0000 | [diff] [blame] | 158 | tailbufsize = count + BUFSIZ; |
| 159 | } |
| 160 | } |
Denis Vlasenko | e8419c9 | 2008-02-19 00:38:10 +0000 | [diff] [blame] | 161 | tailbuf = xmalloc(tailbufsize); |
Glenn L McGrath | 4ef5a84 | 2003-10-31 00:35:59 +0000 | [diff] [blame] | 162 | |
Denis Vlasenko | e8419c9 | 2008-02-19 00:38:10 +0000 | [diff] [blame] | 163 | /* tail the files */ |
Manuel Novoa III | cad5364 | 2003-03-19 09:13:01 +0000 | [diff] [blame] | 164 | fmt = header_fmt + 1; /* Skip header leading newline on first output. */ |
| 165 | i = 0; |
| 166 | do { |
Manuel Novoa III | cad5364 | 2003-03-19 09:13:01 +0000 | [diff] [blame] | 167 | if (nfiles > header_threshhold) { |
| 168 | tail_xprint_header(fmt, argv[i]); |
| 169 | fmt = header_fmt; |
| 170 | } |
| 171 | |
Denis Vlasenko | e8419c9 | 2008-02-19 00:38:10 +0000 | [diff] [blame] | 172 | /* Optimizing count-bytes case if the file is seekable. |
| 173 | * Beware of backing up too far. |
| 174 | * Also we exclude files with size 0 (because of /proc/xxx) */ |
Denis Vlasenko | 69ca5a7 | 2008-03-23 03:28:40 +0000 | [diff] [blame] | 175 | if (COUNT_BYTES && !from_top) { |
| 176 | off_t current = lseek(fds[i], 0, SEEK_END); |
| 177 | if (current > 0) { |
Denis Vlasenko | e8419c9 | 2008-02-19 00:38:10 +0000 | [diff] [blame] | 178 | if (count == 0) |
| 179 | continue; /* showing zero lines is easy :) */ |
Denis Vlasenko | 69ca5a7 | 2008-03-23 03:28:40 +0000 | [diff] [blame] | 180 | current -= count; |
| 181 | if (current < 0) |
| 182 | current = 0; |
| 183 | xlseek(fds[i], current, SEEK_SET); |
| 184 | bb_copyfd_size(fds[i], STDOUT_FILENO, count); |
| 185 | continue; |
Denis Vlasenko | e8419c9 | 2008-02-19 00:38:10 +0000 | [diff] [blame] | 186 | } |
| 187 | } |
| 188 | |
Manuel Novoa III | cad5364 | 2003-03-19 09:13:01 +0000 | [diff] [blame] | 189 | buf = tailbuf; |
| 190 | taillen = 0; |
| 191 | seen = 1; |
Denis Vlasenko | e8419c9 | 2008-02-19 00:38:10 +0000 | [diff] [blame] | 192 | newlines_seen = 0; |
Manuel Novoa III | cad5364 | 2003-03-19 09:13:01 +0000 | [diff] [blame] | 193 | while ((nread = tail_read(fds[i], buf, tailbufsize-taillen)) > 0) { |
Matt Kraai | 55bccf3 | 2001-01-05 02:57:53 +0000 | [diff] [blame] | 194 | if (from_top) { |
Manuel Novoa III | cad5364 | 2003-03-19 09:13:01 +0000 | [diff] [blame] | 195 | nwrite = nread; |
| 196 | if (seen < count) { |
Denis Vlasenko | e31f721 | 2006-12-22 16:06:16 +0000 | [diff] [blame] | 197 | if (COUNT_BYTES) { |
Manuel Novoa III | cad5364 | 2003-03-19 09:13:01 +0000 | [diff] [blame] | 198 | nwrite -= (count - seen); |
| 199 | seen = count; |
Glenn L McGrath | 4ef5a84 | 2003-10-31 00:35:59 +0000 | [diff] [blame] | 200 | } else { |
Manuel Novoa III | cad5364 | 2003-03-19 09:13:01 +0000 | [diff] [blame] | 201 | s = buf; |
| 202 | do { |
| 203 | --nwrite; |
Denis Vlasenko | e31f721 | 2006-12-22 16:06:16 +0000 | [diff] [blame] | 204 | if (*s++ == '\n' && ++seen == count) { |
Matt Kraai | 55bccf3 | 2001-01-05 02:57:53 +0000 | [diff] [blame] | 205 | break; |
| 206 | } |
Manuel Novoa III | cad5364 | 2003-03-19 09:13:01 +0000 | [diff] [blame] | 207 | } while (nwrite); |
| 208 | } |
| 209 | } |
Denis Vlasenko | e31f721 | 2006-12-22 16:06:16 +0000 | [diff] [blame] | 210 | xwrite(STDOUT_FILENO, buf + nread - nwrite, nwrite); |
Manuel Novoa III | cad5364 | 2003-03-19 09:13:01 +0000 | [diff] [blame] | 211 | } else if (count) { |
Denis Vlasenko | e31f721 | 2006-12-22 16:06:16 +0000 | [diff] [blame] | 212 | if (COUNT_BYTES) { |
Manuel Novoa III | cad5364 | 2003-03-19 09:13:01 +0000 | [diff] [blame] | 213 | taillen += nread; |
Denis Vlasenko | 77ad97f | 2008-05-13 02:27:31 +0000 | [diff] [blame] | 214 | if (taillen > (int)count) { |
Manuel Novoa III | cad5364 | 2003-03-19 09:13:01 +0000 | [diff] [blame] | 215 | memmove(tailbuf, tailbuf + taillen - count, count); |
| 216 | taillen = count; |
| 217 | } |
Glenn L McGrath | 4ef5a84 | 2003-10-31 00:35:59 +0000 | [diff] [blame] | 218 | } else { |
Manuel Novoa III | cad5364 | 2003-03-19 09:13:01 +0000 | [diff] [blame] | 219 | int k = nread; |
Denis Vlasenko | e8419c9 | 2008-02-19 00:38:10 +0000 | [diff] [blame] | 220 | int newlines_in_buf = 0; |
Manuel Novoa III | cad5364 | 2003-03-19 09:13:01 +0000 | [diff] [blame] | 221 | |
Denis Vlasenko | e8419c9 | 2008-02-19 00:38:10 +0000 | [diff] [blame] | 222 | do { /* count '\n' in last read */ |
| 223 | k--; |
Manuel Novoa III | cad5364 | 2003-03-19 09:13:01 +0000 | [diff] [blame] | 224 | if (buf[k] == '\n') { |
Denis Vlasenko | e8419c9 | 2008-02-19 00:38:10 +0000 | [diff] [blame] | 225 | newlines_in_buf++; |
Matt Kraai | 55bccf3 | 2001-01-05 02:57:53 +0000 | [diff] [blame] | 226 | } |
Denis Vlasenko | e8419c9 | 2008-02-19 00:38:10 +0000 | [diff] [blame] | 227 | } while (k); |
Manuel Novoa III | cad5364 | 2003-03-19 09:13:01 +0000 | [diff] [blame] | 228 | |
Denis Vlasenko | 77ad97f | 2008-05-13 02:27:31 +0000 | [diff] [blame] | 229 | if (newlines_seen + newlines_in_buf < (int)count) { |
Denis Vlasenko | e8419c9 | 2008-02-19 00:38:10 +0000 | [diff] [blame] | 230 | newlines_seen += newlines_in_buf; |
Manuel Novoa III | cad5364 | 2003-03-19 09:13:01 +0000 | [diff] [blame] | 231 | taillen += nread; |
Matt Kraai | 55bccf3 | 2001-01-05 02:57:53 +0000 | [diff] [blame] | 232 | } else { |
Denis Vlasenko | e8419c9 | 2008-02-19 00:38:10 +0000 | [diff] [blame] | 233 | int extra = (buf[nread-1] != '\n'); |
Manuel Novoa III | cad5364 | 2003-03-19 09:13:01 +0000 | [diff] [blame] | 234 | |
Denis Vlasenko | e8419c9 | 2008-02-19 00:38:10 +0000 | [diff] [blame] | 235 | k = newlines_seen + newlines_in_buf + extra - count; |
Manuel Novoa III | cad5364 | 2003-03-19 09:13:01 +0000 | [diff] [blame] | 236 | s = tailbuf; |
| 237 | while (k) { |
| 238 | if (*s == '\n') { |
Denis Vlasenko | e8419c9 | 2008-02-19 00:38:10 +0000 | [diff] [blame] | 239 | k--; |
Manuel Novoa III | cad5364 | 2003-03-19 09:13:01 +0000 | [diff] [blame] | 240 | } |
Denis Vlasenko | e8419c9 | 2008-02-19 00:38:10 +0000 | [diff] [blame] | 241 | s++; |
Manuel Novoa III | cad5364 | 2003-03-19 09:13:01 +0000 | [diff] [blame] | 242 | } |
Manuel Novoa III | cad5364 | 2003-03-19 09:13:01 +0000 | [diff] [blame] | 243 | taillen += nread - (s - tailbuf); |
| 244 | memmove(tailbuf, s, taillen); |
Denis Vlasenko | e8419c9 | 2008-02-19 00:38:10 +0000 | [diff] [blame] | 245 | newlines_seen = count - extra; |
Matt Kraai | 55bccf3 | 2001-01-05 02:57:53 +0000 | [diff] [blame] | 246 | } |
Denis Vlasenko | 77ad97f | 2008-05-13 02:27:31 +0000 | [diff] [blame] | 247 | if (tailbufsize < (size_t)taillen + BUFSIZ) { |
Manuel Novoa III | cad5364 | 2003-03-19 09:13:01 +0000 | [diff] [blame] | 248 | tailbufsize = taillen + BUFSIZ; |
| 249 | tailbuf = xrealloc(tailbuf, tailbufsize); |
Matt Kraai | 55bccf3 | 2001-01-05 02:57:53 +0000 | [diff] [blame] | 250 | } |
Eric Andersen | d5fa3e3 | 2000-08-02 16:42:58 +0000 | [diff] [blame] | 251 | } |
Manuel Novoa III | cad5364 | 2003-03-19 09:13:01 +0000 | [diff] [blame] | 252 | buf = tailbuf + taillen; |
Eric Andersen | d5fa3e3 | 2000-08-02 16:42:58 +0000 | [diff] [blame] | 253 | } |
Denis Vlasenko | e8419c9 | 2008-02-19 00:38:10 +0000 | [diff] [blame] | 254 | } /* while (tail_read() > 0) */ |
Manuel Novoa III | cad5364 | 2003-03-19 09:13:01 +0000 | [diff] [blame] | 255 | if (!from_top) { |
Denis Vlasenko | e31f721 | 2006-12-22 16:06:16 +0000 | [diff] [blame] | 256 | xwrite(STDOUT_FILENO, tailbuf, taillen); |
Matt Kraai | 55bccf3 | 2001-01-05 02:57:53 +0000 | [diff] [blame] | 257 | } |
Manuel Novoa III | cad5364 | 2003-03-19 09:13:01 +0000 | [diff] [blame] | 258 | } while (++i < nfiles); |
| 259 | |
| 260 | buf = xrealloc(tailbuf, BUFSIZ); |
| 261 | |
| 262 | fmt = NULL; |
Matt Kraai | 55bccf3 | 2001-01-05 02:57:53 +0000 | [diff] [blame] | 263 | |
Denis Vlasenko | e31f721 | 2006-12-22 16:06:16 +0000 | [diff] [blame] | 264 | if (FOLLOW) while (1) { |
Matt Kraai | 55bccf3 | 2001-01-05 02:57:53 +0000 | [diff] [blame] | 265 | sleep(sleep_period); |
Manuel Novoa III | cad5364 | 2003-03-19 09:13:01 +0000 | [diff] [blame] | 266 | i = 0; |
| 267 | do { |
| 268 | if (nfiles > header_threshhold) { |
| 269 | fmt = header_fmt; |
Matt Kraai | 55bccf3 | 2001-01-05 02:57:53 +0000 | [diff] [blame] | 270 | } |
Denis Vlasenko | 226002e | 2007-10-05 19:17:16 +0000 | [diff] [blame] | 271 | while ((nread = tail_read(fds[i], buf, BUFSIZ)) > 0) { |
Manuel Novoa III | cad5364 | 2003-03-19 09:13:01 +0000 | [diff] [blame] | 272 | if (fmt) { |
| 273 | tail_xprint_header(fmt, argv[i]); |
| 274 | fmt = NULL; |
| 275 | } |
Denis Vlasenko | e31f721 | 2006-12-22 16:06:16 +0000 | [diff] [blame] | 276 | xwrite(STDOUT_FILENO, buf, nread); |
Matt Kraai | 55bccf3 | 2001-01-05 02:57:53 +0000 | [diff] [blame] | 277 | } |
Manuel Novoa III | cad5364 | 2003-03-19 09:13:01 +0000 | [diff] [blame] | 278 | } while (++i < nfiles); |
Matt Kraai | 55bccf3 | 2001-01-05 02:57:53 +0000 | [diff] [blame] | 279 | } |
Bernhard Reutner-Fischer | d9c2d5f | 2007-04-04 20:29:15 +0000 | [diff] [blame] | 280 | if (ENABLE_FEATURE_CLEAN_UP) { |
| 281 | free(fds); |
| 282 | } |
| 283 | return G.status; |
Matt Kraai | 55bccf3 | 2001-01-05 02:57:53 +0000 | [diff] [blame] | 284 | } |