X-Git-Url: https://git.cworth.org/git?p=tar;a=blobdiff_plain;f=src%2Fbuffer.c;h=8147def1961246dfdef3f3704432416431c6f932;hp=8edc257fe63ba27510eae8a4153ee2b02c48bf0b;hb=22f1eb8bc17e5be72dd23d42d6aaa60196ac22e6;hpb=00fa13ff3f2d5b6e2a94c5e948c38616ff7ad37a diff --git a/src/buffer.c b/src/buffer.c index 8edc257..8147def 100644 --- a/src/buffer.c +++ b/src/buffer.c @@ -1,7 +1,8 @@ /* Buffer management for tar. Copyright (C) 1988, 1992, 1993, 1994, 1996, 1997, 1999, 2000, 2001, - 2003, 2004, 2005, 2006, 2007, 2008, 2009 Free Software Foundation, Inc. + 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010 Free Software + Foundation, Inc. Written by John Gilmore, on 1985-08-25. @@ -35,9 +36,6 @@ /* Number of retries before giving up on read. */ #define READ_ERROR_MAX 10 -/* Globbing pattern to append to volume label if initial match failed. */ -#define VOLUME_LABEL_APPEND " Volume [1-9]*" - /* Variables. */ static tarlong prev_written; /* bytes written on previous volumes */ @@ -203,6 +201,7 @@ enum compress_type { ct_compress, ct_gzip, ct_bzip2, + ct_lzip, ct_lzma, ct_lzop, ct_xz @@ -220,12 +219,13 @@ struct zip_magic static struct zip_magic const magic[] = { { ct_tar }, { ct_none, }, - { ct_compress, 2, "\037\235", "compress", "-Z" }, - { ct_gzip, 2, "\037\213", "gzip", "-z" }, - { ct_bzip2, 3, "BZh", "bzip2", "-j" }, - { ct_lzma, 6, "\xFFLZMA", "lzma", "--lzma" }, /* FIXME: ???? */ - { ct_lzop, 4, "\211LZO", "lzop", "--lzop" }, - { ct_xz, 6, "\0xFD7zXZ", "-J" }, + { ct_compress, 2, "\037\235", COMPRESS_PROGRAM, "-Z" }, + { ct_gzip, 2, "\037\213", GZIP_PROGRAM, "-z" }, + { ct_bzip2, 3, "BZh", BZIP2_PROGRAM, "-j" }, + { ct_lzip, 4, "LZIP", LZIP_PROGRAM, "--lzip" }, + { ct_lzma, 6, "\xFFLZMA", LZMA_PROGRAM, "--lzma" }, + { ct_lzop, 4, "\211LZO", LZOP_PROGRAM, "--lzop" }, + { ct_xz, 6, "\0xFD7zXZ", XZ_PROGRAM, "-J" }, }; #define NMAGIC (sizeof(magic)/sizeof(magic[0])) @@ -265,6 +265,37 @@ check_compressed_archive (bool *pshort) return ct_none; } +/* Guess if the archive is seekable. */ +static void +guess_seekable_archive () +{ + struct stat st; + + if (subcommand_option == DELETE_SUBCOMMAND) + { + /* The current code in delete.c is based on the assumption that + skip_member() reads all data from the archive. So, we should + make sure it won't use seeks. On the other hand, the same code + depends on the ability to backspace a record in the archive, + so setting seekable_archive to false is technically incorrect. + However, it is tested only in skip_member(), so it's not a + problem. */ + seekable_archive = false; + } + + if (seek_option != -1) + { + seekable_archive = !!seek_option; + return; + } + + if (!multi_volume_option && !use_compress_program_option + && fstat (archive, &st) == 0) + seekable_archive = S_ISREG (st.st_mode); + else + seekable_archive = false; +} + /* Open an archive named archive_name_array[0]. Detect if it is a compressed archive of known type and use corresponding decompression program if so */ @@ -295,7 +326,7 @@ open_compressed_archive () ERROR ((0, 0, _("This does not look like a tar archive"))); set_comression_program_by_suffix (archive_name_array[0], NULL); if (!use_compress_program_option) - return archive; + return archive; break; default: @@ -306,7 +337,7 @@ open_compressed_archive () /* FD is not needed any more */ rmtclose (archive); - + hit_eof = false; /* It might have been set by find_next_block in check_compressed_archive */ @@ -565,6 +596,8 @@ _open_archive (enum access_mode wanted_access) { case ACCESS_READ: archive = open_compressed_archive (); + if (archive >= 0) + guess_seekable_archive (); break; case ACCESS_WRITE: @@ -679,6 +712,19 @@ archive_read_error (void) return; } +static bool +archive_is_dev () +{ + struct stat st; + + if (fstat (archive, &st)) + { + stat_diag (*archive_name_cursor); + return false; + } + return S_ISBLK (st.st_mode) || S_ISCHR (st.st_mode); +} + static void short_read (size_t status) { @@ -690,7 +736,8 @@ short_read (size_t status) if (left && left % BLOCKSIZE == 0 && verbose_option - && record_start_block == 0 && status != 0) + && record_start_block == 0 && status != 0 + && archive_is_dev ()) { unsigned long rsize = status / BLOCKSIZE; WARN ((0, 0, @@ -809,16 +856,16 @@ seek_archive (off_t size) off_t start = current_block_ordinal (); off_t offset; off_t nrec, nblk; - off_t skipped = (blocking_factor - (current_block - record_start)); - - size -= skipped * BLOCKSIZE; + off_t skipped = (blocking_factor - (current_block - record_start)) + * BLOCKSIZE; - if (size < record_size) + if (size <= skipped) return 0; - /* FIXME: flush? */ - + /* Compute number of records to skip */ - nrec = size / record_size; + nrec = (size - skipped) / record_size; + if (nrec == 0) + return 0; offset = rmtlseek (archive, nrec * record_size, SEEK_CUR); if (offset < 0) return offset; @@ -1084,6 +1131,7 @@ new_volume (enum access_mode mode) case ACCESS_READ: archive = rmtopen (*archive_name_cursor, O_RDONLY, MODE_RW, rsh_command_option); + guess_seekable_archive (); break; case ACCESS_WRITE: @@ -1119,7 +1167,7 @@ read_header0 (struct tar_stat_info *info) enum read_header rc; tar_stat_init (info); - rc = read_header_primitive (false, info); + rc = read_header (¤t_header, info, read_header_auto); if (rc == HEADER_SUCCESS) { set_next_block_after (current_header); @@ -1167,17 +1215,42 @@ try_new_volume () { case XGLTYPE: { - if (!read_header0 (&dummy)) - return false; + tar_stat_init (&dummy); + if (read_header (&header, &dummy, read_header_x_global) + != HEADER_SUCCESS_EXTENDED) + { + ERROR ((0, 0, _("This does not look like a tar archive"))); + return false; + } + xheader_decode (&dummy); /* decodes values from the global header */ tar_stat_destroy (&dummy); - if (!real_s_name) - { - /* We have read the extended header of the first member in - this volume. Put it back, so next read_header works as - expected. */ - current_block = record_start; - } + + /* The initial global header must be immediately followed by + an extended PAX header for the first member in this volume. + However, in some cases tar may split volumes in the middle + of a PAX header. This is incorrect, and should be fixed + in the future versions. In the meantime we must be + prepared to correctly list and extract such archives. + + If this happens, the following call to read_header returns + HEADER_FAILURE, which is ignored. + + See also tests/multiv07.at */ + + switch (read_header (&header, &dummy, read_header_auto)) + { + case HEADER_SUCCESS: + set_next_block_after (header); + break; + + case HEADER_FAILURE: + break; + + default: + ERROR ((0, 0, _("This does not look like a tar archive"))); + return false; + } break; } @@ -1264,31 +1337,57 @@ try_new_volume () } -/* Check the LABEL block against the volume label, seen as a globbing +#define VOLUME_TEXT " Volume " +#define VOLUME_TEXT_LEN (sizeof VOLUME_TEXT - 1) + +char * +drop_volume_label_suffix (const char *label) +{ + const char *p; + size_t len = strlen (label); + + if (len < 1) + return NULL; + + for (p = label + len - 1; p > label && isdigit ((unsigned char) *p); p--) + ; + if (p > label && p - (VOLUME_TEXT_LEN - 1) > label) + { + p -= VOLUME_TEXT_LEN - 1; + if (memcmp (p, VOLUME_TEXT, VOLUME_TEXT_LEN) == 0) + { + char *s = xmalloc ((len = p - label) + 1); + memcpy (s, label, len); + s[len] = 0; + return s; + } + } + + return NULL; +} + +/* Check LABEL against the volume label, seen as a globbing pattern. Return true if the pattern matches. In case of failure, retry matching a volume sequence number before giving up in multi-volume mode. */ static bool -check_label_pattern (union block *label) +check_label_pattern (const char *label) { char *string; bool result; - if (! memchr (label->header.name, '\0', sizeof label->header.name)) - return false; - - if (fnmatch (volume_label_option, label->header.name, 0) == 0) + if (fnmatch (volume_label_option, label, 0) == 0) return true; if (!multi_volume_option) return false; - string = xmalloc (strlen (volume_label_option) - + sizeof VOLUME_LABEL_APPEND + 1); - strcpy (string, volume_label_option); - strcat (string, VOLUME_LABEL_APPEND); - result = fnmatch (string, label->header.name, 0) == 0; - free (string); + string = drop_volume_label_suffix (label); + if (string) + { + result = fnmatch (string, volume_label_option, 0) == 0; + free (string); + } return result; } @@ -1297,14 +1396,43 @@ check_label_pattern (union block *label) static void match_volume_label (void) { - union block *label = find_next_block (); - - if (!label) + if (!volume_label) + { + union block *label = find_next_block (); + + if (!label) + FATAL_ERROR ((0, 0, _("Archive not labeled to match %s"), + quote (volume_label_option))); + if (label->header.typeflag == GNUTYPE_VOLHDR) + { + if (memchr (label->header.name, '\0', sizeof label->header.name)) + assign_string (&volume_label, label->header.name); + else + { + volume_label = xmalloc (sizeof (label->header.name) + 1); + memcpy (volume_label, label->header.name, + sizeof (label->header.name)); + volume_label[sizeof (label->header.name)] = 0; + } + } + else if (label->header.typeflag == XGLTYPE) + { + struct tar_stat_info st; + tar_stat_init (&st); + xheader_read (&st.xhdr, label, + OFF_FROM_HEADER (label->header.size)); + xheader_decode (&st); + tar_stat_destroy (&st); + } + } + + if (!volume_label) FATAL_ERROR ((0, 0, _("Archive not labeled to match %s"), quote (volume_label_option))); - if (!check_label_pattern (label)) + + if (!check_label_pattern (volume_label)) FATAL_ERROR ((0, 0, _("Volume %s does not match %s"), - quote_n (0, label->header.name), + quote_n (0, volume_label), quote_n (1, volume_label_option))); }