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: qtv --rsyncable 9 10// gzip.net version allows all options for all commands. 11USE_GZIP(NEWTOY(gzip, "ncdfk123456789[-123456789]", TOYFLAG_USR|TOYFLAG_BIN)) 12USE_GUNZIP(NEWTOY(gunzip, "cdfk123456789[-123456789]", TOYFLAG_USR|TOYFLAG_BIN)) 13USE_ZCAT(NEWTOY(zcat, "cdfk123456789[-123456789]", TOYFLAG_USR|TOYFLAG_BIN)) 14 15config GZIP 16 bool "gzip" 17 default n 18 help 19 usage: gzip [-19cdfk] [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 -# Compression level 1-9 (1:fastest, 6:default, 9:best) 30 31config GUNZIP 32 bool "gunzip" 33 default y 34 help 35 usage: gunzip [-cfk] [FILE...] 36 37 Decompress files. With no files, decompresses stdin to stdout. 38 On success, the input files are removed and replaced by new 39 files without the .gz suffix. 40 41 -c Output to stdout (act as zcat) 42 -f Force: allow read from tty 43 -k Keep input files (default is to remove) 44 45config ZCAT 46 bool "zcat" 47 default y 48 help 49 usage: zcat [FILE...] 50 51 Decompress files to stdout. Like `gzip -dc`. 52 53 -f Force: allow read from tty 54*/ 55 56#define FORCE_FLAGS 57#define FOR_gzip 58#include "toys.h" 59 60GLOBALS( 61 int level; 62) 63 64// Use assembly optimized zlib code? 65#if CFG_TOYBOX_LIBZ 66#include <zlib.h> 67 68// Read from in_fd, write to out_fd, decompress if dd else compress 69static int do_deflate(int in_fd, int out_fd, int dd, int level) 70{ 71 int len, err = 0; 72 char *b = "r"; 73 gzFile gz; 74 75 if (!dd) { 76 sprintf(b = toybuf, "w%d", level); 77 if (out_fd == 1) out_fd = xdup(out_fd); 78 } 79 if (!(gz = gzdopen(dd ? in_fd : out_fd, b))) perror_exit("gzdopen"); 80 if (dd) { 81 if (gzdirect(gz)) error_exit("not gzip"); 82 while ((len = gzread(gz, toybuf, sizeof(toybuf))) > 0) 83 if (len != writeall(out_fd, toybuf, len)) break; 84 } else { 85 while ((len = read(in_fd, toybuf, sizeof(toybuf))) > 0) 86 if (len != gzwrite(gz, toybuf, len)) break; 87 } 88 89 err = !!len; 90 if (len>0 || err == Z_ERRNO) perror_msg(dd ? "write" : "read"); 91 if (len<0) 92 error_msg("%s%s: %s", "gz", dd ? "read" : "write", gzerror(gz, &len)); 93 94 if (gzclose(gz) != Z_OK) perror_msg("gzclose"), err++; 95 96 return err; 97} 98 99// Use toybox's builtin lib/deflate.c 100#else 101 102// Read from in_fd, write to out_fd, decompress if dd else compress 103static int do_deflate(int in_fd, int out_fd, int dd, int level) 104{ 105 int x; 106 107 if (dd) WOULD_EXIT(x, gunzip_fd(in_fd, out_fd)); 108 else WOULD_EXIT(x, gzip_fd(in_fd, out_fd)); 109 110 return x; 111} 112 113#endif 114 115static void do_gzip(int ifd, char *in) 116{ 117 struct stat sb; 118 char *out = 0; 119 int ofd = 0; 120 121 // Are we writing to stdout? 122 if (!ifd || FLAG(c)) ofd = 1; 123 if (isatty(ifd)) { 124 if (!FLAG(f)) return error_msg("%s:need -f to read TTY"+3*!!ifd, in); 125 else ofd = 1; 126 } 127 128 // Are we reading file.gz to write to file? 129 if (!ofd) { 130 if (fstat(ifd, &sb)) return perror_msg("%s", in); 131 132 // Add or remove .gz suffix as necessary 133 if (!FLAG(d)) out = xmprintf("%s%s", in, ".gz"); 134 else if ((out = strend(in, ".gz"))>in) out = xstrndup(in, out-in); 135 else return error_msg("no .gz: %s", in); 136 137 ofd = xcreate(out, O_CREAT|O_WRONLY|WARN_ONLY|(O_EXCL*!FLAG(f)),sb.st_mode); 138 if (ofd == -1) return; 139 } 140 141 if (do_deflate(ifd, ofd, FLAG(d), TT.level)) in = out; 142 143 if (out) { 144 struct timespec times[] = {sb.st_atim, sb.st_mtim}; 145 146 if (utimensat(AT_FDCWD, out, times, 0)) perror_exit("utimensat"); 147 if (chmod(out, sb.st_mode)) perror_exit("chmod"); 148 close(ofd); 149 if (!FLAG(k) && in && unlink(in)) perror_msg("unlink %s", in); 150 free(out); 151 } 152} 153 154void gzip_main(void) 155{ 156 // This depends on 1-9 being at the end of the option list 157 for (TT.level = 0; TT.level<9; TT.level++) 158 if ((toys.optflags>>TT.level)&1) break; 159 if (!(TT.level = 9-TT.level)) TT.level = 6; 160 161 loopfiles(toys.optargs, do_gzip); 162} 163 164void gunzip_main(void) 165{ 166 toys.optflags |= FLAG_d; 167 gzip_main(); 168} 169 170void zcat_main(void) 171{ 172 toys.optflags |= (FLAG_c|FLAG_d); 173 gzip_main(); 174} 175