1 /* gzip.c - gzip/gunzip/zcat
2 *
3 * Copyright 2017 The Android Open Source Project
4 *
5 * See http://refspecs.linuxfoundation.org/LSB_4.1.0/LSB-Core-generic/LSB-Core-generic/gzip.html
6 * GZIP RFC: http://www.ietf.org/rfc/rfc1952.txt
7 *
8 * TODO: qv --rsyncable
9
10 // gzip.net version allows all options for all commands.
11 USE_GZIP(NEWTOY(gzip, "n(no-name)cdfkt123456789[-123456789]", TOYFLAG_USR|TOYFLAG_BIN))
12 USE_GUNZIP(NEWTOY(gunzip, "cdfkt123456789[-123456789]", TOYFLAG_USR|TOYFLAG_BIN))
13 USE_ZCAT(NEWTOY(zcat, "cdfkt123456789[-123456789]", TOYFLAG_USR|TOYFLAG_BIN))
14
15 config GZIP
16 bool "gzip"
17 default n
18 help
19 usage: gzip [-19cdfkt] [FILE...]
20
21 Compress files. With no files, compresses stdin to stdout.
22 On success, the input files are removed and replaced by new
23 files with the .gz suffix.
24
25 -c Output to stdout
26 -d Decompress (act as gunzip)
27 -f Force: allow overwrite of output file
28 -k Keep input files (default is to remove)
29 -t Test integrity
30 -# Compression level 1-9 (1:fastest, 6:default, 9:best)
31
32 config GUNZIP
33 bool "gunzip"
34 default y
35 help
36 usage: gunzip [-cfkt] [FILE...]
37
38 Decompress files. With no files, decompresses stdin to stdout.
39 On success, the input files are removed and replaced by new
40 files without the .gz suffix.
41
42 -c Output to stdout (act as zcat)
43 -f Force: allow read from tty
44 -k Keep input files (default is to remove)
45 -t Test integrity
46
47 config ZCAT
48 bool "zcat"
49 default y
50 help
51 usage: zcat [-f] [FILE...]
52
53 Decompress files to stdout. Like `gzip -dc`.
54
55 -f Force: allow read from tty
56 */
57
58 #define FORCE_FLAGS
59 #define FOR_gzip
60 #include "toys.h"
61
GLOBALS(int level;)62 GLOBALS(
63 int level;
64 )
65
66 // Use assembly optimized zlib code?
67 #if CFG_TOYBOX_LIBZ
68 #include <zlib.h>
69
70 // Read from in_fd, write to out_fd, decompress if dd else compress
71 static int do_deflate(int in_fd, int out_fd, int dd, int level)
72 {
73 int len, err = 0;
74 char *b = "r";
75 gzFile gz;
76
77 if (!dd) {
78 sprintf(b = toybuf, "w%d", level);
79 if (out_fd == 1) out_fd = xdup(out_fd);
80 }
81 if (!(gz = gzdopen(dd ? in_fd : out_fd, b))) perror_exit("gzdopen");
82 if (dd) {
83 if (gzdirect(gz)) error_exit("not gzip");
84 while ((len = gzread(gz, toybuf, sizeof(toybuf))) > 0)
85 if (len != writeall(out_fd, toybuf, len)) break;
86 } else {
87 while ((len = read(in_fd, toybuf, sizeof(toybuf))) > 0)
88 if (len != gzwrite(gz, toybuf, len)) break;
89 }
90
91 err = !!len;
92 if (len>0 || err == Z_ERRNO) perror_msg(dd ? "write" : "read");
93 if (len<0)
94 error_msg("%s%s: %s", "gz", dd ? "read" : "write", gzerror(gz, &len));
95
96 if (gzclose(gz) != Z_OK) perror_msg("gzclose"), err++;
97
98 return err;
99 }
100
101 // Use toybox's builtin lib/deflate.c
102 #else
103
104 // Read from in_fd, write to out_fd, decompress if dd else compress
105 static int do_deflate(int in_fd, int out_fd, int dd, int level)
106 {
107 int x;
108
109 if (dd) WOULD_EXIT(x, gunzip_fd(in_fd, out_fd));
110 else WOULD_EXIT(x, gzip_fd(in_fd, out_fd));
111
112 return x;
113 }
114
115 #endif
116
do_gzip(int ifd,char * in)117 static void do_gzip(int ifd, char *in)
118 {
119 struct stat sb;
120 char *out = 0;
121 int ofd = FLAG(t) ? xopen("/dev/null", O_WRONLY) : 0;
122
123 // Are we writing to stdout?
124 if (!ifd || FLAG(c)) ofd = 1;
125 if (isatty(ifd)) {
126 if (!FLAG(f)) return error_msg("%s:need -f to read TTY"+3*!!ifd, in);
127 else ofd = 1;
128 }
129
130 // Are we reading file.gz to write to file?
131 if (!ofd) {
132 if (fstat(ifd, &sb)) return perror_msg_raw(in);
133
134 // Add or remove .gz suffix as necessary
135 if (!FLAG(d)) out = xmprintf("%s%s", in, ".gz");
136 else if ((out = strend(in, ".gz"))>in) out = xstrndup(in, out-in);
137 else if ((out = strend(in, ".tgz"))>in)
138 out = xmprintf("%.*s.tar", (int)(out-in), in);
139 else return error_msg("no .gz: %s", in);
140 ofd = xcreate(out, O_CREAT|O_WRONLY|WARN_ONLY|O_EXCL*!FLAG(f), sb.st_mode);
141 if (ofd == -1) return;
142 }
143
144 if (do_deflate(ifd, ofd, FLAG(d), TT.level)) in = out;
145
146 if (out) {
147 struct timespec times[] = {sb.st_atim, sb.st_mtim};
148
149 if (utimensat(AT_FDCWD, out, times, 0)) perror_exit("utimensat");
150 if (chmod(out, sb.st_mode)) perror_exit("chmod");
151 close(ofd);
152 if (!FLAG(k) && in && unlink(in)) perror_msg("unlink %s", in);
153 free(out);
154 }
155 }
156
gzip_main(void)157 void gzip_main(void)
158 {
159 // This depends on 1-9 being at the end of the option list
160 for (TT.level = 0; TT.level<9; TT.level++)
161 if ((toys.optflags>>TT.level)&1) break;
162 if (!(TT.level = 9-TT.level)) TT.level = 6;
163
164 if (FLAG(t)) toys.optflags |= FLAG_d;
165
166 loopfiles(toys.optargs, do_gzip);
167 }
168
gunzip_main(void)169 void gunzip_main(void)
170 {
171 toys.optflags |= FLAG_d;
172 gzip_main();
173 }
174
zcat_main(void)175 void zcat_main(void)
176 {
177 toys.optflags |= (FLAG_c|FLAG_d);
178 gzip_main();
179 }
180