1 /* vi: set sw=4 ts=4: */
2 /*
3 * wc implementation for busybox
4 *
5 * Copyright (C) 2003 Manuel Novoa III <mjn3@codepoet.org>
6 *
7 * Licensed under GPLv2 or later, see file LICENSE in this source tree.
8 */
9 /* Mar 16, 2003 Manuel Novoa III (mjn3@codepoet.org)
10 *
11 * Rewritten to fix a number of problems and do some size optimizations.
12 * Problems in the previous busybox implementation (besides bloat) included:
13 * 1) broken 'wc -c' optimization (read note below)
14 * 2) broken handling of '-' args
15 * 3) no checking of ferror on EOF returns
16 * 4) isprint() wasn't considered when word counting.
17 *
18 * NOTES:
19 *
20 * The previous busybox wc attempted an optimization using stat for the
21 * case of counting chars only. I omitted that because it was broken.
22 * It didn't take into account the possibility of input coming from a
23 * pipe, or input from a file with file pointer not at the beginning.
24 *
25 * To implement such a speed optimization correctly, not only do you
26 * need the size, but also the file position. Note also that the
27 * file position may be past the end of file. Consider the example
28 * (adapted from example in gnu wc.c)
29 *
30 * echo hello > /tmp/testfile &&
31 * (dd ibs=1k skip=1 count=0 &> /dev/null; wc -c) < /tmp/testfile
32 *
33 * for which 'wc -c' should output '0'.
34 */
35 //config:config WC
36 //config: bool "wc (4.5 kb)"
37 //config: default y
38 //config: help
39 //config: wc is used to print the number of bytes, words, and lines,
40 //config: in specified files.
41 //config:
42 //config:config FEATURE_WC_LARGE
43 //config: bool "Support very large counts"
44 //config: default y
45 //config: depends on WC
46 //config: help
47 //config: Use "unsigned long long" for counter variables.
48
49 //applet:IF_WC(APPLET(wc, BB_DIR_USR_BIN, BB_SUID_DROP))
50
51 //kbuild:lib-$(CONFIG_WC) += wc.o
52
53 /* BB_AUDIT SUSv3 compliant. */
54 /* http://www.opengroup.org/onlinepubs/007904975/utilities/wc.html */
55
56 #include "libbb.h"
57 #include "unicode.h"
58
59 #if !ENABLE_LOCALE_SUPPORT
60 # undef isprint
61 # undef isspace
62 # define isprint(c) ((unsigned)((c) - 0x20) <= (0x7e - 0x20))
63 # define isspace(c) ((c) == ' ')
64 #endif
65
66 #if ENABLE_FEATURE_WC_LARGE
67 # define COUNT_T unsigned long long
68 # define COUNT_FMT "llu"
69 #else
70 # define COUNT_T unsigned
71 # define COUNT_FMT "u"
72 #endif
73
74 /* We support -m even when UNICODE_SUPPORT is off,
75 * we just don't advertise it in help text,
76 * since it is the same as -c in this case.
77 */
78
79 //usage:#define wc_trivial_usage
80 //usage: "[-c"IF_UNICODE_SUPPORT("m")"lwL] [FILE]..."
81 //usage:
82 //usage:#define wc_full_usage "\n\n"
83 //usage: "Count lines, words, and bytes for FILEs (or stdin)\n"
84 //usage: "\n -c Count bytes"
85 //usage: IF_UNICODE_SUPPORT(
86 //usage: "\n -m Count characters"
87 //usage: )
88 //usage: "\n -l Count newlines"
89 //usage: "\n -w Count words"
90 //usage: "\n -L Print longest line length"
91 //usage:
92 //usage:#define wc_example_usage
93 //usage: "$ wc /etc/passwd\n"
94 //usage: " 31 46 1365 /etc/passwd\n"
95
96 /* Order is important if we want to be compatible with
97 * column order in "wc -cmlwL" output:
98 */
99 enum {
100 WC_LINES = 0, /* -l */
101 WC_WORDS = 1, /* -w */
102 WC_UNICHARS = 2, /* -m */
103 WC_BYTES = 3, /* -c */
104 WC_LENGTH = 4, /* -L */
105 NUM_WCS = 5,
106 };
107
108 int wc_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
wc_main(int argc UNUSED_PARAM,char ** argv)109 int wc_main(int argc UNUSED_PARAM, char **argv)
110 {
111 const char *arg;
112 const char *start_fmt = " %9"COUNT_FMT + 1;
113 const char *fname_fmt = " %s\n";
114 COUNT_T *pcounts;
115 COUNT_T counts[NUM_WCS];
116 COUNT_T totals[NUM_WCS];
117 int num_files;
118 smallint status = EXIT_SUCCESS;
119 unsigned print_type;
120
121 init_unicode();
122
123 print_type = getopt32(argv, "lwmcL");
124
125 if (print_type == 0) {
126 print_type = (1 << WC_LINES) | (1 << WC_WORDS) | (1 << WC_BYTES);
127 }
128
129 argv += optind;
130 if (!argv[0]) {
131 *--argv = (char *) bb_msg_standard_input;
132 fname_fmt = "\n";
133 }
134 if (!argv[1]) { /* zero or one filename? */
135 if (!((print_type-1) & print_type)) /* exactly one option? */
136 start_fmt = "%"COUNT_FMT;
137 }
138
139 memset(totals, 0, sizeof(totals));
140
141 pcounts = counts;
142
143 num_files = 0;
144 while ((arg = *argv++) != NULL) {
145 FILE *fp;
146 const char *s;
147 unsigned u;
148 unsigned linepos;
149 smallint in_word;
150
151 ++num_files;
152 fp = fopen_or_warn_stdin(arg);
153 if (!fp) {
154 status = EXIT_FAILURE;
155 continue;
156 }
157
158 memset(counts, 0, sizeof(counts));
159 linepos = 0;
160 in_word = 0;
161
162 while (1) {
163 int c;
164 /* Our -w doesn't match GNU wc exactly... oh well */
165
166 c = getc(fp);
167 if (c == EOF) {
168 if (ferror(fp)) {
169 bb_simple_perror_msg(arg);
170 status = EXIT_FAILURE;
171 }
172 goto DO_EOF; /* Treat an EOF as '\r'. */
173 }
174
175 /* Cater for -c and -m */
176 ++counts[WC_BYTES];
177 if (unicode_status != UNICODE_ON /* every byte is a new char */
178 || (c & 0xc0) != 0x80 /* it isn't a 2nd+ byte of a Unicode char */
179 ) {
180 ++counts[WC_UNICHARS];
181 }
182
183 if (isprint_asciionly(c)) { /* FIXME: not unicode-aware */
184 ++linepos;
185 if (!isspace(c)) {
186 in_word = 1;
187 continue;
188 }
189 } else if ((unsigned)(c - 9) <= 4) {
190 /* \t 9
191 * \n 10
192 * \v 11
193 * \f 12
194 * \r 13
195 */
196 if (c == '\t') {
197 linepos = (linepos | 7) + 1;
198 } else { /* '\n', '\r', '\f', or '\v' */
199 DO_EOF:
200 if (linepos > counts[WC_LENGTH]) {
201 counts[WC_LENGTH] = linepos;
202 }
203 if (c == '\n') {
204 ++counts[WC_LINES];
205 }
206 if (c != '\v') {
207 linepos = 0;
208 }
209 }
210 } else {
211 continue;
212 }
213
214 counts[WC_WORDS] += in_word;
215 in_word = 0;
216 if (c == EOF) {
217 break;
218 }
219 }
220
221 fclose_if_not_stdin(fp);
222
223 if (totals[WC_LENGTH] < counts[WC_LENGTH]) {
224 totals[WC_LENGTH] = counts[WC_LENGTH];
225 }
226 totals[WC_LENGTH] -= counts[WC_LENGTH];
227
228 OUTPUT:
229 /* coreutils wc tries hard to print pretty columns
230 * (saves results for all files, finds max col len etc...)
231 * we won't try that hard, it will bloat us too much */
232 s = start_fmt;
233 u = 0;
234 do {
235 if (print_type & (1 << u)) {
236 printf(s, pcounts[u]);
237 s = " %9"COUNT_FMT; /* Ok... restore the leading space. */
238 }
239 totals[u] += pcounts[u];
240 } while (++u < NUM_WCS);
241 printf(fname_fmt, arg);
242 }
243
244 /* If more than one file was processed, we want the totals. To save some
245 * space, we set the pcounts ptr to the totals array. This has the side
246 * effect of trashing the totals array after outputting it, but that's
247 * irrelavent since we no longer need it. */
248 if (num_files > 1) {
249 num_files = 0; /* Make sure we don't get here again. */
250 arg = "total";
251 pcounts = totals;
252 --argv;
253 goto OUTPUT;
254 }
255
256 fflush_stdout_and_exit(status);
257 }
258