PArtial Changelog update. I'm still on vacation (I'm at a campground
[oweals/busybox.git] / dd.c
1 /* vi: set sw=4 ts=4: */
2 /*
3  * Mini dd implementation for busybox
4  *
5  *
6  * Copyright (C) 2000 by Matt Kraai <kraai@alumni.carnegiemellon.edu>
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License as published by
10  * the Free Software Foundation; either version 2 of the License, or
11  * (at your option) any later version.
12  *
13  * This program is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16  * General Public License for more details.
17  *
18  * You should have received a copy of the GNU General Public License
19  * along with this program; if not, write to the Free Software
20  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
21  *
22  */
23
24 #include <sys/types.h>
25 #include <stdlib.h>
26 #include <stdio.h>
27 #include <unistd.h>
28 #include <string.h>
29 #include <fcntl.h>
30 #include "busybox.h"
31
32
33 static const struct suffix_mult dd_suffixes[] = {
34         { "c", 1 },
35         { "w", 2 },
36         { "b", 512 },
37         { "kD", 1000 },
38         { "k", 1024 },
39         { "MD", 1000000 },
40         { "M", 1048576 },
41         { "GD", 1000000000 },
42         { "G", 1073741824 },
43         { NULL, 0 }
44 };
45
46 int dd_main(int argc, char **argv)
47 {
48         int i, ifd, ofd, oflag, sync_flag = FALSE, trunc = TRUE;
49         size_t in_full = 0, in_part = 0, out_full = 0, out_part = 0;
50         size_t bs = 512, count = -1;
51         ssize_t n;
52         off_t seek = 0, skip = 0;
53         FILE *statusfp;
54         char *infile = NULL, *outfile = NULL, *buf;
55
56         for (i = 1; i < argc; i++) {
57                 if (strncmp("bs=", argv[i], 3) == 0)
58                         bs = parse_number(argv[i]+3, dd_suffixes);
59                 else if (strncmp("count=", argv[i], 6) == 0)
60                         count = parse_number(argv[i]+6, dd_suffixes);
61                 else if (strncmp("seek=", argv[i], 5) == 0)
62                         seek = parse_number(argv[i]+5, dd_suffixes);
63                 else if (strncmp("skip=", argv[i], 5) == 0)
64                         skip = parse_number(argv[i]+5, dd_suffixes);
65                 else if (strncmp("if=", argv[i], 3) == 0)
66                         infile = argv[i]+3;
67                 else if (strncmp("of=", argv[i], 3) == 0)
68                         outfile = argv[i]+3;
69                 else if (strncmp("conv=", argv[i], 5) == 0) {
70                         buf = argv[i]+5;
71                         while (1) {
72                                 if (strncmp("notrunc", buf, 7) == 0) {
73                                         trunc = FALSE;
74                                         buf += 7;
75                                 } else if (strncmp("sync", buf, 4) == 0) {
76                                         sync_flag = TRUE;
77                                         buf += 4;
78                                 } else {
79                                         error_msg_and_die("invalid conversion `%s'", argv[i]+5);
80                                 }
81                                 if (buf[0] == '\0')
82                                         break;
83                                 if (buf[0] == ',')
84                                         buf++;
85                         }
86                 } else
87                         show_usage();
88         }
89
90         buf = xmalloc(bs);
91
92         if (infile != NULL) {
93                 if ((ifd = open(infile, O_RDONLY)) < 0)
94                         perror_msg_and_die("%s", infile);
95         } else {
96                 ifd = STDIN_FILENO;
97                 infile = "standard input";
98         }
99
100         if (outfile != NULL) {
101                 oflag = O_WRONLY | O_CREAT;
102
103                 if (!seek && trunc)
104                         oflag |= O_TRUNC;
105
106                 if ((ofd = open(outfile, oflag, 0666)) < 0)
107                         perror_msg_and_die("%s", outfile);
108
109                 if (seek && trunc) {
110                         if (ftruncate(ofd, seek * bs) < 0)
111                                 perror_msg_and_die("%s", outfile);
112                 }
113
114                 statusfp = stdout;
115         } else {
116                 ofd = STDOUT_FILENO;
117                 outfile = "standard output";
118                 statusfp = stderr;
119         }
120
121         if (skip) {
122                 if (lseek(ifd, skip * bs, SEEK_CUR) < 0)
123                         perror_msg_and_die("%s", infile);
124         }
125
126         if (seek) {
127                 if (lseek(ofd, seek * bs, SEEK_CUR) < 0)
128                         perror_msg_and_die("%s", outfile);
129         }
130
131         while (in_full + in_part != count) {
132                 n = safe_read(ifd, buf, bs);
133                 if (n < 0)
134                         perror_msg_and_die("%s", infile);
135                 if (n == 0)
136                         break;
137                 if (n == bs)
138                         in_full++;
139                 else
140                         in_part++;
141                 if (sync_flag) {
142                         memset(buf + n, '\0', bs - n);
143                         n = bs;
144                 }
145                 n = full_write(ofd, buf, n);
146                 if (n < 0)
147                         perror_msg_and_die("%s", outfile);
148                 if (n == bs)
149                         out_full++;
150                 else
151                         out_part++;
152         }
153
154         fprintf(statusfp, "%ld+%ld records in\n", (long)in_full, (long)in_part);
155         fprintf(statusfp, "%ld+%ld records out\n", (long)out_full, (long)out_part);
156
157         return EXIT_SUCCESS;
158 }