1 /* vi: set sw=4 ts=4: */
2 /*
3 * Mini comm implementation for busybox
4 *
5 * Copyright (C) 2005 by Robert Sullivan <cogito.ergo.cogito@gmail.com>
6 *
7 * Licensed under GPLv2 or later, see file LICENSE in this source tree.
8 */
9 //config:config COMM
10 //config: bool "comm (4.2 kb)"
11 //config: default y
12 //config: help
13 //config: comm is used to compare two files line by line and return
14 //config: a three-column output.
15
16 //applet:IF_COMM(APPLET(comm, BB_DIR_USR_BIN, BB_SUID_DROP))
17
18 //kbuild:lib-$(CONFIG_COMM) += comm.o
19
20 //usage:#define comm_trivial_usage
21 //usage: "[-123] FILE1 FILE2"
22 //usage:#define comm_full_usage "\n\n"
23 //usage: "Compare FILE1 with FILE2\n"
24 //usage: "\n -1 Suppress lines unique to FILE1"
25 //usage: "\n -2 Suppress lines unique to FILE2"
26 //usage: "\n -3 Suppress lines common to both files"
27
28 #include "libbb.h"
29
30 #define COMM_OPT_1 (1 << 0)
31 #define COMM_OPT_2 (1 << 1)
32 #define COMM_OPT_3 (1 << 2)
33
34 /* writeline outputs the input given, appropriately aligned according to class */
writeline(char * line,int class)35 static void writeline(char *line, int class)
36 {
37 int flags = option_mask32;
38 if (class == 0) {
39 if (flags & COMM_OPT_1)
40 return;
41 } else if (class == 1) {
42 if (flags & COMM_OPT_2)
43 return;
44 if (!(flags & COMM_OPT_1))
45 putchar('\t');
46 } else /*if (class == 2)*/ {
47 if (flags & COMM_OPT_3)
48 return;
49 if (!(flags & COMM_OPT_1))
50 putchar('\t');
51 if (!(flags & COMM_OPT_2))
52 putchar('\t');
53 }
54 puts(line);
55 }
56
57 int comm_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
comm_main(int argc UNUSED_PARAM,char ** argv)58 int comm_main(int argc UNUSED_PARAM, char **argv)
59 {
60 char *thisline[2];
61 FILE *stream[2];
62 int i;
63 int order;
64
65 getopt32(argv, "^" "123" "\0" "=2");
66 argv += optind;
67
68 for (i = 0; i < 2; ++i) {
69 stream[i] = xfopen_stdin(argv[i]);
70 }
71
72 order = 0;
73 thisline[1] = thisline[0] = NULL;
74 while (1) {
75 if (order <= 0) {
76 free(thisline[0]);
77 thisline[0] = xmalloc_fgetline(stream[0]);
78 }
79 if (order >= 0) {
80 free(thisline[1]);
81 thisline[1] = xmalloc_fgetline(stream[1]);
82 }
83
84 i = !thisline[0] + (!thisline[1] << 1);
85 if (i)
86 break;
87 order = strcmp(thisline[0], thisline[1]);
88
89 if (order >= 0)
90 writeline(thisline[1], order ? 1 : 2);
91 else
92 writeline(thisline[0], 0);
93 }
94
95 /* EOF at least on one of the streams */
96 i &= 1;
97 if (thisline[i]) {
98 /* stream[i] is not at EOF yet */
99 /* we did not print thisline[i] yet */
100 char *p = thisline[i];
101 writeline(p, i);
102 while (1) {
103 free(p);
104 p = xmalloc_fgetline(stream[i]);
105 if (!p)
106 break;
107 writeline(p, i);
108 }
109 }
110
111 if (ENABLE_FEATURE_CLEAN_UP) {
112 fclose(stream[0]);
113 fclose(stream[1]);
114 }
115
116 return EXIT_SUCCESS;
117 }
118