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Diffstat (limited to 'contrib/libarchive/examples/minitar/minitar.c')
-rw-r--r-- | contrib/libarchive/examples/minitar/minitar.c | 421 |
1 files changed, 421 insertions, 0 deletions
diff --git a/contrib/libarchive/examples/minitar/minitar.c b/contrib/libarchive/examples/minitar/minitar.c new file mode 100644 index 0000000..7e90111 --- /dev/null +++ b/contrib/libarchive/examples/minitar/minitar.c @@ -0,0 +1,421 @@ +/*- + * This file is in the public domain. + * Do with it as you will. + */ + +/*- + * This is a compact "tar" program whose primary goal is small size. + * Statically linked, it can be very small indeed. This serves a number + * of goals: + * o a testbed for libarchive (to check for link pollution), + * o a useful tool for space-constrained systems (boot floppies, etc), + * o a place to experiment with new implementation ideas for bsdtar, + * o a small program to demonstrate libarchive usage. + * + * Use the following macros to suppress features: + * NO_BZIP2 - Implies NO_BZIP2_CREATE and NO_BZIP2_EXTRACT + * NO_BZIP2_CREATE - Suppress bzip2 compression support. + * NO_BZIP2_EXTRACT - Suppress bzip2 auto-detection and decompression. + * NO_COMPRESS - Implies NO_COMPRESS_CREATE and NO_COMPRESS_EXTRACT + * NO_COMPRESS_CREATE - Suppress compress(1) compression support + * NO_COMPRESS_EXTRACT - Suppress compress(1) auto-detect and decompression. + * NO_CREATE - Suppress all archive creation support. + * NO_CPIO_EXTRACT - Suppress auto-detect and dearchiving of cpio archives. + * NO_GZIP - Implies NO_GZIP_CREATE and NO_GZIP_EXTRACT + * NO_GZIP_CREATE - Suppress gzip compression support. + * NO_GZIP_EXTRACT - Suppress gzip auto-detection and decompression. + * NO_LOOKUP - Try to avoid getpw/getgr routines, which can be very large + * NO_TAR_EXTRACT - Suppress tar extraction + * + * With all of the above macros defined (except NO_TAR_EXTRACT), you + * get a very small program that can recognize and extract essentially + * any uncompressed tar archive. On FreeBSD 5.1, this minimal program + * is under 64k, statically linked, which compares rather favorably to + * main(){printf("hello, world");} + * which is over 60k statically linked on the same operating system. + * Without any of the above macros, you get a static executable of + * about 180k with a lot of very sophisticated modern features. + * Obviously, it's trivial to add support for ISO, Zip, mtree, + * lzma/xz, etc. Just fill in the appropriate setup calls. + */ + +#include <sys/types.h> +__FBSDID("$FreeBSD$"); + +#include <sys/stat.h> + +#include <archive.h> +#include <archive_entry.h> +#include <fcntl.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <unistd.h> + +#ifndef NO_CREATE +#include "tree.h" +#endif + +/* + * NO_CREATE implies NO_BZIP2_CREATE and NO_GZIP_CREATE and NO_COMPRESS_CREATE. + */ +#ifdef NO_CREATE +#undef NO_BZIP2_CREATE +#define NO_BZIP2_CREATE +#undef NO_COMPRESS_CREATE +#define NO_COMPRESS_CREATE +#undef NO_GZIP_CREATE +#define NO_GZIP_CREATE +#endif + +/* + * The combination of NO_BZIP2_CREATE and NO_BZIP2_EXTRACT is + * equivalent to NO_BZIP2. + */ +#ifdef NO_BZIP2_CREATE +#ifdef NO_BZIP2_EXTRACT +#undef NO_BZIP2 +#define NO_BZIP2 +#endif +#endif + +#ifdef NO_BZIP2 +#undef NO_BZIP2_EXTRACT +#define NO_BZIP2_EXTRACT +#undef NO_BZIP2_CREATE +#define NO_BZIP2_CREATE +#endif + +/* + * The combination of NO_COMPRESS_CREATE and NO_COMPRESS_EXTRACT is + * equivalent to NO_COMPRESS. + */ +#ifdef NO_COMPRESS_CREATE +#ifdef NO_COMPRESS_EXTRACT +#undef NO_COMPRESS +#define NO_COMPRESS +#endif +#endif + +#ifdef NO_COMPRESS +#undef NO_COMPRESS_EXTRACT +#define NO_COMPRESS_EXTRACT +#undef NO_COMPRESS_CREATE +#define NO_COMPRESS_CREATE +#endif + +/* + * The combination of NO_GZIP_CREATE and NO_GZIP_EXTRACT is + * equivalent to NO_GZIP. + */ +#ifdef NO_GZIP_CREATE +#ifdef NO_GZIP_EXTRACT +#undef NO_GZIP +#define NO_GZIP +#endif +#endif + +#ifdef NO_GZIP +#undef NO_GZIP_EXTRACT +#define NO_GZIP_EXTRACT +#undef NO_GZIP_CREATE +#define NO_GZIP_CREATE +#endif + +#ifndef NO_CREATE +static void create(const char *filename, int compress, const char **argv); +#endif +static void errmsg(const char *); +static void extract(const char *filename, int do_extract, int flags); +static int copy_data(struct archive *, struct archive *); +static void msg(const char *); +static void usage(void); + +static int verbose = 0; + +int +main(int argc, const char **argv) +{ + const char *filename = NULL; + int compress, flags, mode, opt; + + (void)argc; + mode = 'x'; + verbose = 0; + compress = '\0'; + flags = ARCHIVE_EXTRACT_TIME; + + /* Among other sins, getopt(3) pulls in printf(3). */ + while (*++argv != NULL && **argv == '-') { + const char *p = *argv + 1; + + while ((opt = *p++) != '\0') { + switch (opt) { +#ifndef NO_CREATE + case 'c': + mode = opt; + break; +#endif + case 'f': + if (*p != '\0') + filename = p; + else + filename = *++argv; + p += strlen(p); + break; +#ifndef NO_BZIP2_CREATE + case 'j': + compress = opt; + break; +#endif + case 'p': + flags |= ARCHIVE_EXTRACT_PERM; + flags |= ARCHIVE_EXTRACT_ACL; + flags |= ARCHIVE_EXTRACT_FFLAGS; + break; + case 't': + mode = opt; + break; + case 'v': + verbose++; + break; + case 'x': + mode = opt; + break; +#ifndef NO_BZIP2_CREATE + case 'y': + compress = opt; + break; +#endif +#ifndef NO_COMPRESS_CREATE + case 'Z': + compress = opt; + break; +#endif +#ifndef NO_GZIP_CREATE + case 'z': + compress = opt; + break; +#endif + default: + usage(); + } + } + } + + switch (mode) { +#ifndef NO_CREATE + case 'c': + create(filename, compress, argv); + break; +#endif + case 't': + extract(filename, 0, flags); + break; + case 'x': + extract(filename, 1, flags); + break; + } + + return (0); +} + + +#ifndef NO_CREATE +static char buff[16384]; + +static void +create(const char *filename, int compress, const char **argv) +{ + struct archive *a; + struct archive *disk; + struct archive_entry *entry; + ssize_t len; + int fd; + + a = archive_write_new(); + switch (compress) { +#ifndef NO_BZIP2_CREATE + case 'j': case 'y': + archive_write_set_compression_bzip2(a); + break; +#endif +#ifndef NO_COMPRESS_CREATE + case 'Z': + archive_write_set_compression_compress(a); + break; +#endif +#ifndef NO_GZIP_CREATE + case 'z': + archive_write_set_compression_gzip(a); + break; +#endif + default: + archive_write_set_compression_none(a); + break; + } + archive_write_set_format_ustar(a); + if (strcmp(filename, "-") == 0) + filename = NULL; + archive_write_open_file(a, filename); + + disk = archive_read_disk_new(); +#ifndef NO_LOOKUP + archive_read_disk_set_standard_lookup(disk); +#endif + while (*argv != NULL) { + struct tree *t = tree_open(*argv); + while (tree_next(t)) { + entry = archive_entry_new(); + archive_entry_set_pathname(entry, tree_current_path(t)); + archive_read_disk_entry_from_file(disk, entry, -1, + tree_current_stat(t)); + if (verbose) { + msg("a "); + msg(tree_current_path(t)); + } + archive_write_header(a, entry); + fd = open(tree_current_access_path(t), O_RDONLY); + len = read(fd, buff, sizeof(buff)); + while (len > 0) { + archive_write_data(a, buff, len); + len = read(fd, buff, sizeof(buff)); + } + close(fd); + archive_entry_free(entry); + if (verbose) + msg("\n"); + } + argv++; + } + archive_write_close(a); + archive_write_finish(a); +} +#endif + +static void +extract(const char *filename, int do_extract, int flags) +{ + struct archive *a; + struct archive *ext; + struct archive_entry *entry; + int r; + + a = archive_read_new(); + ext = archive_write_disk_new(); + archive_write_disk_set_options(ext, flags); +#ifndef NO_BZIP2_EXTRACT + archive_read_support_compression_bzip2(a); +#endif +#ifndef NO_GZIP_EXTRACT + archive_read_support_compression_gzip(a); +#endif +#ifndef NO_COMPRESS_EXTRACT + archive_read_support_compression_compress(a); +#endif +#ifndef NO_TAR_EXTRACT + archive_read_support_format_tar(a); +#endif +#ifndef NO_CPIO_EXTRACT + archive_read_support_format_cpio(a); +#endif +#ifndef NO_LOOKUP + archive_write_disk_set_standard_lookup(ext); +#endif + if (filename != NULL && strcmp(filename, "-") == 0) + filename = NULL; + if ((r = archive_read_open_file(a, filename, 10240))) { + errmsg(archive_error_string(a)); + errmsg("\n"); + exit(r); + } + for (;;) { + r = archive_read_next_header(a, &entry); + if (r == ARCHIVE_EOF) + break; + if (r != ARCHIVE_OK) { + errmsg(archive_error_string(a)); + errmsg("\n"); + exit(1); + } + if (verbose && do_extract) + msg("x "); + if (verbose || !do_extract) + msg(archive_entry_pathname(entry)); + if (do_extract) { + r = archive_write_header(ext, entry); + if (r != ARCHIVE_OK) + errmsg(archive_error_string(a)); + else + copy_data(a, ext); + } + if (verbose || !do_extract) + msg("\n"); + } + archive_read_close(a); + archive_read_finish(a); + exit(0); +} + +static int +copy_data(struct archive *ar, struct archive *aw) +{ + int r; + const void *buff; + size_t size; + off_t offset; + + for (;;) { + r = archive_read_data_block(ar, &buff, &size, &offset); + if (r == ARCHIVE_EOF) { + errmsg(archive_error_string(ar)); + return (ARCHIVE_OK); + } + if (r != ARCHIVE_OK) + return (r); + r = archive_write_data_block(aw, buff, size, offset); + if (r != ARCHIVE_OK) { + errmsg(archive_error_string(ar)); + return (r); + } + } +} + +static void +msg(const char *m) +{ + write(1, m, strlen(m)); +} + +static void +errmsg(const char *m) +{ + write(2, m, strlen(m)); +} + +static void +usage(void) +{ +/* Many program options depend on compile options. */ + const char *m = "Usage: minitar [-" +#ifndef NO_CREATE + "c" +#endif +#ifndef NO_BZIP2 + "j" +#endif + "tvx" +#ifndef NO_BZIP2 + "y" +#endif +#ifndef NO_COMPRESS + "Z" +#endif +#ifndef NO_GZIP + "z" +#endif + "] [-f file] [file]\n"; + + errmsg(m); + exit(1); +} |