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Diffstat (limited to 'contrib/tar/src/buffer.c')
| -rw-r--r-- | contrib/tar/src/buffer.c | 1600 |
1 files changed, 1600 insertions, 0 deletions
diff --git a/contrib/tar/src/buffer.c b/contrib/tar/src/buffer.c new file mode 100644 index 0000000..1d164b4 --- /dev/null +++ b/contrib/tar/src/buffer.c @@ -0,0 +1,1600 @@ +/* Buffer management for tar. + + Copyright 1988, 1992, 1993, 1994, 1996, 1997, 1999, 2000, 2001 Free + Software Foundation, Inc. + + Written by John Gilmore, on 1985-08-25. + + This program is free software; you can redistribute it and/or modify it + under the terms of the GNU General Public License as published by the + Free Software Foundation; either version 2, or (at your option) any later + version. + + This program is distributed in the hope that it will be useful, but + WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General + Public License for more details. + + You should have received a copy of the GNU General Public License along + with this program; if not, write to the Free Software Foundation, Inc., + 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ + +#include "system.h" + +#include <signal.h> + +#if MSDOS +# include <process.h> +#endif + +#if XENIX +# include <sys/inode.h> +#endif + +#include <fnmatch.h> +#include <human.h> +#include <quotearg.h> + +#include "common.h" +#include "rmt.h" + +#define PREAD 0 /* read file descriptor from pipe() */ +#define PWRITE 1 /* write file descriptor from pipe() */ + +/* 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 */ +static tarlong bytes_written; /* bytes written on this volume */ + +/* FIXME: The following variables should ideally be static to this + module. However, this cannot be done yet. The cleanup continues! */ + +union block *record_start; /* start of record of archive */ +union block *record_end; /* last+1 block of archive record */ +union block *current_block; /* current block of archive */ +enum access_mode access_mode; /* how do we handle the archive */ +off_t records_read; /* number of records read from this archive */ +off_t records_written; /* likewise, for records written */ + +static struct stat archive_stat; /* stat block for archive file */ + +static off_t record_start_block; /* block ordinal at record_start */ + +/* Where we write list messages (not errors, not interactions) to. Stdout + unless we're writing a pipe, in which case stderr. */ +FILE *stdlis; + +static void backspace_output PARAMS ((void)); +static int new_volume PARAMS ((enum access_mode)); +static void archive_write_error PARAMS ((ssize_t)) __attribute__ ((noreturn)); +static void archive_read_error PARAMS ((void)); + +#if !MSDOS +/* Obnoxious test to see if dimwit is trying to dump the archive. */ +dev_t ar_dev; +ino_t ar_ino; +#endif + +/* PID of child program, if compress_option or remote archive access. */ +static pid_t child_pid; + +/* Error recovery stuff */ +static int read_error_count; + +/* Have we hit EOF yet? */ +static int hit_eof; + +/* Checkpointing counter */ +static int checkpoint; + +/* We're reading, but we just read the last block and its time to update. */ +/* As least EXTERN like this one as possible. FIXME! */ +extern int time_to_start_writing; + +int file_to_switch_to = -1; /* if remote update, close archive, and use + this descriptor to write to */ + +static int volno = 1; /* which volume of a multi-volume tape we're + on */ +static int global_volno = 1; /* volume number to print in external + messages */ + +/* The pointer save_name, which is set in function dump_file() of module + create.c, points to the original long filename instead of the new, + shorter mangled name that is set in start_header() of module create.c. + The pointer save_name is only used in multi-volume mode when the file + being processed is non-sparse; if a file is split between volumes, the + save_name is used in generating the LF_MULTIVOL record on the second + volume. (From Pierce Cantrell, 1991-08-13.) */ + +char *save_name; /* name of the file we are currently writing */ +off_t save_totsize; /* total size of file we are writing, only + valid if save_name is nonzero */ +off_t save_sizeleft; /* where we are in the file we are writing, + only valid if save_name is nonzero */ + +bool write_archive_to_stdout; + +/* Used by flush_read and flush_write to store the real info about saved + names. */ +static char *real_s_name; +static off_t real_s_totsize; +static off_t real_s_sizeleft; + +/* Functions. */ + +void +print_total_written (void) +{ + tarlong written = prev_written + bytes_written; + char bytes[sizeof (tarlong) * CHAR_BIT]; + char abbr[LONGEST_HUMAN_READABLE + 1]; + char rate[LONGEST_HUMAN_READABLE + 1]; + double seconds; + +#if HAVE_CLOCK_GETTIME + struct timespec now; + if (clock_gettime (CLOCK_REALTIME, &now) == 0) + seconds = ((now.tv_sec - start_timespec.tv_sec) + + (now.tv_nsec - start_timespec.tv_nsec) / 1e9); + else +#endif + seconds = time (0) - start_time; + + sprintf (bytes, TARLONG_FORMAT, written); + + /* Amanda 2.4.1p1 looks for "Total bytes written: [0-9][0-9]*". */ + fprintf (stderr, _("Total bytes written: %s (%sB, %sB/s)\n"), bytes, + human_readable ((uintmax_t) written, abbr, 1, -1024), + (0 < seconds && written / seconds < (uintmax_t) -1 + ? human_readable ((uintmax_t) (written / seconds), rate, 1, -1024) + : "?")); +} + +/* Compute and return the block ordinal at current_block. */ +off_t +current_block_ordinal (void) +{ + return record_start_block + (current_block - record_start); +} + +/* If the EOF flag is set, reset it, as well as current_block, etc. */ +void +reset_eof (void) +{ + if (hit_eof) + { + hit_eof = 0; + current_block = record_start; + record_end = record_start + blocking_factor; + access_mode = ACCESS_WRITE; + } +} + +/* Return the location of the next available input or output block. + Return zero for EOF. Once we have returned zero, we just keep returning + it, to avoid accidentally going on to the next file on the tape. */ +union block * +find_next_block (void) +{ + if (current_block == record_end) + { + if (hit_eof) + return 0; + flush_archive (); + if (current_block == record_end) + { + hit_eof = 1; + return 0; + } + } + return current_block; +} + +/* Indicate that we have used all blocks up thru BLOCK. + FIXME: should the arg have an off-by-1? */ +void +set_next_block_after (union block *block) +{ + while (block >= current_block) + current_block++; + + /* Do *not* flush the archive here. If we do, the same argument to + set_next_block_after could mean the next block (if the input record + is exactly one block long), which is not what is intended. */ + + if (current_block > record_end) + abort (); +} + +/* Return the number of bytes comprising the space between POINTER + through the end of the current buffer of blocks. This space is + available for filling with data, or taking data from. POINTER is + usually (but not always) the result previous find_next_block call. */ +size_t +available_space_after (union block *pointer) +{ + return record_end->buffer - pointer->buffer; +} + +/* Close file having descriptor FD, and abort if close unsuccessful. */ +static void +xclose (int fd) +{ + if (close (fd) != 0) + close_error (_("(pipe)")); +} + +/* Duplicate file descriptor FROM into becoming INTO. + INTO is closed first and has to be the next available slot. */ +static void +xdup2 (int from, int into) +{ + if (from != into) + { + int status = close (into); + + if (status != 0 && errno != EBADF) + { + int e = errno; + FATAL_ERROR ((0, e, _("Cannot close"))); + } + status = dup (from); + if (status != into) + { + if (status < 0) + { + int e = errno; + FATAL_ERROR ((0, e, _("Cannot dup"))); + } + abort (); + } + xclose (from); + } +} + +#if MSDOS + +/* Set ARCHIVE for writing, then compressing an archive. */ +static void +child_open_for_compress (void) +{ + FATAL_ERROR ((0, 0, _("Cannot use compressed or remote archives"))); +} + +/* Set ARCHIVE for uncompressing, then reading an archive. */ +static void +child_open_for_uncompress (void) +{ + FATAL_ERROR ((0, 0, _("Cannot use compressed or remote archives"))); +} + +#else /* not MSDOS */ + +/* Return nonzero if NAME is the name of a regular file, or if the file + does not exist (so it would be created as a regular file). */ +static int +is_regular_file (const char *name) +{ + struct stat stbuf; + + if (stat (name, &stbuf) == 0) + return S_ISREG (stbuf.st_mode); + else + return errno == ENOENT; +} + +static ssize_t +write_archive_buffer (void) +{ + ssize_t status; + ssize_t written = 0; + + while (0 <= (status = rmtwrite (archive, record_start->buffer + written, + record_size - written))) + { + written += status; + if (written == record_size + || _isrmt (archive) + || ! (S_ISFIFO (archive_stat.st_mode) + || S_ISSOCK (archive_stat.st_mode))) + break; + } + + return written ? written : status; +} + +/* Set ARCHIVE for writing, then compressing an archive. */ +static void +child_open_for_compress (void) +{ + int parent_pipe[2]; + int child_pipe[2]; + pid_t grandchild_pid; + int wait_status; + + xpipe (parent_pipe); + child_pid = xfork (); + + if (child_pid > 0) + { + /* The parent tar is still here! Just clean up. */ + + archive = parent_pipe[PWRITE]; + xclose (parent_pipe[PREAD]); + return; + } + + /* The new born child tar is here! */ + + program_name = _("tar (child)"); + + xdup2 (parent_pipe[PREAD], STDIN_FILENO); + xclose (parent_pipe[PWRITE]); + + /* Check if we need a grandchild tar. This happens only if either: + a) we are writing stdout: to force reblocking; + b) the file is to be accessed by rmt: compressor doesn't know how; + c) the file is not a plain file. */ + + if (strcmp (archive_name_array[0], "-") != 0 + && !_remdev (archive_name_array[0]) + && is_regular_file (archive_name_array[0])) + { + if (backup_option) + maybe_backup_file (archive_name_array[0], 1); + + /* We don't need a grandchild tar. Open the archive and launch the + compressor. */ + + archive = creat (archive_name_array[0], MODE_RW); + if (archive < 0) + { + int saved_errno = errno; + + if (backup_option) + undo_last_backup (); + errno = saved_errno; + open_fatal (archive_name_array[0]); + } + xdup2 (archive, STDOUT_FILENO); + execlp (use_compress_program_option, use_compress_program_option, + (char *) 0); + exec_fatal (use_compress_program_option); + } + + /* We do need a grandchild tar. */ + + xpipe (child_pipe); + grandchild_pid = xfork (); + + if (grandchild_pid == 0) + { + /* The newborn grandchild tar is here! Launch the compressor. */ + + program_name = _("tar (grandchild)"); + + xdup2 (child_pipe[PWRITE], STDOUT_FILENO); + xclose (child_pipe[PREAD]); + execlp (use_compress_program_option, use_compress_program_option, + (char *) 0); + exec_fatal (use_compress_program_option); + } + + /* The child tar is still here! */ + + /* Prepare for reblocking the data from the compressor into the archive. */ + + xdup2 (child_pipe[PREAD], STDIN_FILENO); + xclose (child_pipe[PWRITE]); + + if (strcmp (archive_name_array[0], "-") == 0) + archive = STDOUT_FILENO; + else + { + archive = rmtcreat (archive_name_array[0], MODE_RW, rsh_command_option); + if (archive < 0) + open_fatal (archive_name_array[0]); + } + + /* Let's read out of the stdin pipe and write an archive. */ + + while (1) + { + ssize_t status = 0; + char *cursor; + size_t length; + + /* Assemble a record. */ + + for (length = 0, cursor = record_start->buffer; + length < record_size; + length += status, cursor += status) + { + size_t size = record_size - length; + + if (size < BLOCKSIZE) + size = BLOCKSIZE; + status = safe_read (STDIN_FILENO, cursor, size); + if (status <= 0) + break; + } + + if (status < 0) + read_fatal (use_compress_program_option); + + /* Copy the record. */ + + if (status == 0) + { + /* We hit the end of the file. Write last record at + full length, as the only role of the grandchild is + doing proper reblocking. */ + + if (length > 0) + { + memset (record_start->buffer + length, 0, record_size - length); + status = write_archive_buffer (); + if (status != record_size) + archive_write_error (status); + } + + /* There is nothing else to read, break out. */ + break; + } + + status = write_archive_buffer (); + if (status != record_size) + archive_write_error (status); + } + +#if 0 + close_archive (); +#endif + + /* Propagate any failure of the grandchild back to the parent. */ + + while (waitpid (grandchild_pid, &wait_status, 0) == -1) + if (errno != EINTR) + { + waitpid_error (use_compress_program_option); + break; + } + + if (WIFSIGNALED (wait_status)) + { + kill (child_pid, WTERMSIG (wait_status)); + exit_status = TAREXIT_FAILURE; + } + else if (WEXITSTATUS (wait_status) != 0) + exit_status = WEXITSTATUS (wait_status); + + exit (exit_status); +} + +/* Set ARCHIVE for uncompressing, then reading an archive. */ +static void +child_open_for_uncompress (void) +{ + int parent_pipe[2]; + int child_pipe[2]; + pid_t grandchild_pid; + int wait_status; + + xpipe (parent_pipe); + child_pid = xfork (); + + if (child_pid > 0) + { + /* The parent tar is still here! Just clean up. */ + + read_full_records_option = 1; + archive = parent_pipe[PREAD]; + xclose (parent_pipe[PWRITE]); + return; + } + + /* The newborn child tar is here! */ + + program_name = _("tar (child)"); + + xdup2 (parent_pipe[PWRITE], STDOUT_FILENO); + xclose (parent_pipe[PREAD]); + + /* Check if we need a grandchild tar. This happens only if either: + a) we're reading stdin: to force unblocking; + b) the file is to be accessed by rmt: compressor doesn't know how; + c) the file is not a plain file. */ + + if (strcmp (archive_name_array[0], "-") != 0 + && !_remdev (archive_name_array[0]) + && is_regular_file (archive_name_array[0])) + { + /* We don't need a grandchild tar. Open the archive and lauch the + uncompressor. */ + + archive = open (archive_name_array[0], O_RDONLY | O_BINARY, MODE_RW); + if (archive < 0) + open_fatal (archive_name_array[0]); + xdup2 (archive, STDIN_FILENO); + execlp (use_compress_program_option, use_compress_program_option, + "-d", (char *) 0); + exec_fatal (use_compress_program_option); + } + + /* We do need a grandchild tar. */ + + xpipe (child_pipe); + grandchild_pid = xfork (); + + if (grandchild_pid == 0) + { + /* The newborn grandchild tar is here! Launch the uncompressor. */ + + program_name = _("tar (grandchild)"); + + xdup2 (child_pipe[PREAD], STDIN_FILENO); + xclose (child_pipe[PWRITE]); + execlp (use_compress_program_option, use_compress_program_option, + "-d", (char *) 0); + exec_fatal (use_compress_program_option); + } + + /* The child tar is still here! */ + + /* Prepare for unblocking the data from the archive into the + uncompressor. */ + + xdup2 (child_pipe[PWRITE], STDOUT_FILENO); + xclose (child_pipe[PREAD]); + + if (strcmp (archive_name_array[0], "-") == 0) + archive = STDIN_FILENO; + else + archive = rmtopen (archive_name_array[0], O_RDONLY | O_BINARY, + MODE_RW, rsh_command_option); + if (archive < 0) + open_fatal (archive_name_array[0]); + + /* Let's read the archive and pipe it into stdout. */ + + while (1) + { + char *cursor; + size_t maximum; + size_t count; + ssize_t status; + + read_error_count = 0; + + error_loop: + status = rmtread (archive, record_start->buffer, record_size); + if (status < 0) + { + archive_read_error (); + goto error_loop; + } + if (status == 0) + break; + cursor = record_start->buffer; + maximum = status; + while (maximum) + { + count = maximum < BLOCKSIZE ? maximum : BLOCKSIZE; + if (full_write (STDOUT_FILENO, cursor, count) != count) + write_error (use_compress_program_option); + cursor += count; + maximum -= count; + } + } + + xclose (STDOUT_FILENO); +#if 0 + close_archive (); +#endif + + /* Propagate any failure of the grandchild back to the parent. */ + + while (waitpid (grandchild_pid, &wait_status, 0) == -1) + if (errno != EINTR) + { + waitpid_error (use_compress_program_option); + break; + } + + if (WIFSIGNALED (wait_status)) + { + kill (child_pid, WTERMSIG (wait_status)); + exit_status = TAREXIT_FAILURE; + } + else if (WEXITSTATUS (wait_status) != 0) + exit_status = WEXITSTATUS (wait_status); + + exit (exit_status); +} + +#endif /* not MSDOS */ + +/* Check the LABEL block 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 int +check_label_pattern (union block *label) +{ + char *string; + int result; + + if (! memchr (label->header.name, '\0', sizeof label->header.name)) + return 0; + + if (fnmatch (volume_label_option, label->header.name, 0) == 0) + return 1; + + if (!multi_volume_option) + return 0; + + 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); + return result; +} + +/* Open an archive file. The argument specifies whether we are + reading or writing, or both. */ +void +open_archive (enum access_mode wanted_access) +{ + int backed_up_flag = 0; + + stdlis = to_stdout_option ? stderr : stdout; + + if (record_size == 0) + FATAL_ERROR ((0, 0, _("Invalid value for record_size"))); + + if (archive_names == 0) + FATAL_ERROR ((0, 0, _("No archive name given"))); + + current_file_name = 0; + current_link_name = 0; + save_name = 0; + real_s_name = 0; + + if (multi_volume_option) + { + if (verify_option) + FATAL_ERROR ((0, 0, _("Cannot verify multi-volume archives"))); + record_start = valloc (record_size + (2 * BLOCKSIZE)); + if (record_start) + record_start += 2; + } + else + record_start = valloc (record_size); + if (!record_start) + FATAL_ERROR ((0, 0, _("Cannot allocate memory for blocking factor %d"), + blocking_factor)); + + current_block = record_start; + record_end = record_start + blocking_factor; + /* When updating the archive, we start with reading. */ + access_mode = wanted_access == ACCESS_UPDATE ? ACCESS_READ : wanted_access; + + if (use_compress_program_option) + { + if (multi_volume_option) + FATAL_ERROR ((0, 0, _("Cannot use multi-volume compressed archives"))); + if (verify_option) + FATAL_ERROR ((0, 0, _("Cannot verify compressed archives"))); + + switch (wanted_access) + { + case ACCESS_READ: + child_open_for_uncompress (); + break; + + case ACCESS_WRITE: + child_open_for_compress (); + break; + + case ACCESS_UPDATE: + FATAL_ERROR ((0, 0, _("Cannot update compressed archives"))); + break; + } + + if (wanted_access == ACCESS_WRITE + && strcmp (archive_name_array[0], "-") == 0) + stdlis = stderr; + } + else if (strcmp (archive_name_array[0], "-") == 0) + { + read_full_records_option = 1; /* could be a pipe, be safe */ + if (verify_option) + FATAL_ERROR ((0, 0, _("Cannot verify stdin/stdout archive"))); + + switch (wanted_access) + { + case ACCESS_READ: + archive = STDIN_FILENO; + break; + + case ACCESS_WRITE: + archive = STDOUT_FILENO; + stdlis = stderr; + break; + + case ACCESS_UPDATE: + archive = STDIN_FILENO; + stdlis = stderr; + write_archive_to_stdout = 1; + break; + } + } + else if (verify_option) + archive = rmtopen (archive_name_array[0], O_RDWR | O_CREAT | O_BINARY, + MODE_RW, rsh_command_option); + else + switch (wanted_access) + { + case ACCESS_READ: + archive = rmtopen (archive_name_array[0], O_RDONLY | O_BINARY, + MODE_RW, rsh_command_option); + break; + + case ACCESS_WRITE: + if (backup_option) + { + maybe_backup_file (archive_name_array[0], 1); + backed_up_flag = 1; + } + archive = rmtcreat (archive_name_array[0], MODE_RW, + rsh_command_option); + break; + + case ACCESS_UPDATE: + archive = rmtopen (archive_name_array[0], O_RDWR | O_CREAT | O_BINARY, + MODE_RW, rsh_command_option); + break; + } + + if (archive < 0 + || (! _isrmt (archive) && fstat (archive, &archive_stat) < 0)) + { + int saved_errno = errno; + + if (backed_up_flag) + undo_last_backup (); + errno = saved_errno; + open_fatal (archive_name_array[0]); + } + +#if !MSDOS + + /* Detect if outputting to "/dev/null". */ + { + static char const dev_null[] = "/dev/null"; + struct stat dev_null_stat; + + dev_null_output = + (strcmp (archive_name_array[0], dev_null) == 0 + || (! _isrmt (archive) + && S_ISCHR (archive_stat.st_mode) + && stat (dev_null, &dev_null_stat) == 0 + && archive_stat.st_dev == dev_null_stat.st_dev + && archive_stat.st_ino == dev_null_stat.st_ino)); + } + + if (!_isrmt (archive) && S_ISREG (archive_stat.st_mode)) + { + ar_dev = archive_stat.st_dev; + ar_ino = archive_stat.st_ino; + } + else + ar_dev = 0; + +#endif /* not MSDOS */ + +#if MSDOS + setmode (archive, O_BINARY); +#endif + + switch (wanted_access) + { + case ACCESS_UPDATE: + records_written = 0; + case ACCESS_READ: + records_read = 0; + record_end = record_start; /* set up for 1st record = # 0 */ + find_next_block (); /* read it in, check for EOF */ + + if (volume_label_option) + { + union block *label = find_next_block (); + + if (!label) + FATAL_ERROR ((0, 0, _("Archive not labeled to match %s"), + quote (volume_label_option))); + if (!check_label_pattern (label)) + FATAL_ERROR ((0, 0, _("Volume %s does not match %s"), + quote_n (0, label->header.name), + quote_n (1, volume_label_option))); + } + break; + + case ACCESS_WRITE: + records_written = 0; + if (volume_label_option) + { + memset (record_start, 0, BLOCKSIZE); + if (multi_volume_option) + sprintf (record_start->header.name, "%s Volume 1", + volume_label_option); + else + strcpy (record_start->header.name, volume_label_option); + + assign_string (¤t_file_name, record_start->header.name); + + record_start->header.typeflag = GNUTYPE_VOLHDR; + TIME_TO_CHARS (start_time, record_start->header.mtime); + finish_header (record_start); +#if 0 + current_block++; +#endif + } + break; + } +} + +/* Perform a write to flush the buffer. */ +void +flush_write (void) +{ + int copy_back; + ssize_t status; + + if (checkpoint_option && !(++checkpoint % 10)) + WARN ((0, 0, _("Write checkpoint %d"), checkpoint)); + + if (tape_length_option && tape_length_option <= bytes_written) + { + errno = ENOSPC; + status = 0; + } + else if (dev_null_output) + status = record_size; + else + status = write_archive_buffer (); + if (status != record_size && !multi_volume_option) + archive_write_error (status); + + if (status > 0) + { + records_written++; + bytes_written += status; + } + + if (status == record_size) + { + if (multi_volume_option) + { + char *cursor; + + if (!save_name) + { + assign_string (&real_s_name, 0); + real_s_totsize = 0; + real_s_sizeleft = 0; + return; + } + + cursor = save_name + FILESYSTEM_PREFIX_LEN (save_name); + while (ISSLASH (*cursor)) + cursor++; + + assign_string (&real_s_name, cursor); + real_s_totsize = save_totsize; + real_s_sizeleft = save_sizeleft; + } + return; + } + + /* We're multivol. Panic if we didn't get the right kind of response. */ + + /* ENXIO is for the UNIX PC. */ + if (status < 0 && errno != ENOSPC && errno != EIO && errno != ENXIO) + archive_write_error (status); + + /* If error indicates a short write, we just move to the next tape. */ + + if (!new_volume (ACCESS_WRITE)) + return; + + if (totals_option) + prev_written += bytes_written; + bytes_written = 0; + + if (volume_label_option && real_s_name) + { + copy_back = 2; + record_start -= 2; + } + else if (volume_label_option || real_s_name) + { + copy_back = 1; + record_start--; + } + else + copy_back = 0; + + if (volume_label_option) + { + memset (record_start, 0, BLOCKSIZE); + sprintf (record_start->header.name, "%s Volume %d", + volume_label_option, volno); + TIME_TO_CHARS (start_time, record_start->header.mtime); + record_start->header.typeflag = GNUTYPE_VOLHDR; + finish_header (record_start); + } + + if (real_s_name) + { + int tmp; + + if (volume_label_option) + record_start++; + + memset (record_start, 0, BLOCKSIZE); + + /* FIXME: Michael P Urban writes: [a long name file] is being written + when a new volume rolls around [...] Looks like the wrong value is + being preserved in real_s_name, though. */ + + strcpy (record_start->header.name, real_s_name); + record_start->header.typeflag = GNUTYPE_MULTIVOL; + OFF_TO_CHARS (real_s_sizeleft, record_start->header.size); + OFF_TO_CHARS (real_s_totsize - real_s_sizeleft, + record_start->oldgnu_header.offset); + tmp = verbose_option; + verbose_option = 0; + finish_header (record_start); + verbose_option = tmp; + + if (volume_label_option) + record_start--; + } + + status = write_archive_buffer (); + if (status != record_size) + archive_write_error (status); + + bytes_written += status; + + if (copy_back) + { + record_start += copy_back; + memcpy (current_block, + record_start + blocking_factor - copy_back, + copy_back * BLOCKSIZE); + current_block += copy_back; + + if (real_s_sizeleft >= copy_back * BLOCKSIZE) + real_s_sizeleft -= copy_back * BLOCKSIZE; + else if ((real_s_sizeleft + BLOCKSIZE - 1) / BLOCKSIZE <= copy_back) + assign_string (&real_s_name, 0); + else + { + char *cursor = save_name + FILESYSTEM_PREFIX_LEN (save_name); + + while (ISSLASH (*cursor)) + cursor++; + + assign_string (&real_s_name, cursor); + real_s_sizeleft = save_sizeleft; + real_s_totsize = save_totsize; + } + copy_back = 0; + } +} + +/* Handle write errors on the archive. Write errors are always fatal. + Hitting the end of a volume does not cause a write error unless the + write was the first record of the volume. */ +static void +archive_write_error (ssize_t status) +{ + /* It might be useful to know how much was written before the error + occurred. */ + if (totals_option) + { + int e = errno; + print_total_written (); + errno = e; + } + + write_fatal_details (*archive_name_cursor, status, record_size); +} + +/* Handle read errors on the archive. If the read should be retried, + return to the caller. */ +static void +archive_read_error (void) +{ + read_error (*archive_name_cursor); + + if (record_start_block == 0) + FATAL_ERROR ((0, 0, _("At beginning of tape, quitting now"))); + + /* Read error in mid archive. We retry up to READ_ERROR_MAX times and + then give up on reading the archive. */ + + if (read_error_count++ > READ_ERROR_MAX) + FATAL_ERROR ((0, 0, _("Too many errors, quitting"))); + return; +} + +/* Perform a read to flush the buffer. */ +void +flush_read (void) +{ + ssize_t status; /* result from system call */ + size_t left; /* bytes left */ + char *more; /* pointer to next byte to read */ + + if (checkpoint_option && !(++checkpoint % 10)) + WARN ((0, 0, _("Read checkpoint %d"), checkpoint)); + + /* Clear the count of errors. This only applies to a single call to + flush_read. */ + + read_error_count = 0; /* clear error count */ + + if (write_archive_to_stdout && record_start_block != 0) + { + archive = STDOUT_FILENO; + status = write_archive_buffer (); + archive = STDIN_FILENO; + if (status != record_size) + archive_write_error (status); + } + if (multi_volume_option) + { + if (save_name) + { + char *cursor = save_name + FILESYSTEM_PREFIX_LEN (save_name); + + while (ISSLASH (*cursor)) + cursor++; + + assign_string (&real_s_name, cursor); + real_s_sizeleft = save_sizeleft; + real_s_totsize = save_totsize; + } + else + { + assign_string (&real_s_name, 0); + real_s_totsize = 0; + real_s_sizeleft = 0; + } + } + + error_loop: + status = rmtread (archive, record_start->buffer, record_size); + if (status == record_size) + { + records_read++; + return; + } + + if ((status == 0 + || (status < 0 && errno == ENOSPC) + || (status > 0 && !read_full_records_option)) + && multi_volume_option) + { + union block *cursor; + + try_volume: + switch (subcommand_option) + { + case APPEND_SUBCOMMAND: + case CAT_SUBCOMMAND: + case UPDATE_SUBCOMMAND: + if (!new_volume (ACCESS_UPDATE)) + return; + break; + + default: + if (!new_volume (ACCESS_READ)) + return; + break; + } + + vol_error: + status = rmtread (archive, record_start->buffer, record_size); + if (status < 0) + { + archive_read_error (); + goto vol_error; + } + if (status != record_size) + goto short_read; + + cursor = record_start; + + if (cursor->header.typeflag == GNUTYPE_VOLHDR) + { + if (volume_label_option) + { + if (!check_label_pattern (cursor)) + { + WARN ((0, 0, _("Volume %s does not match %s"), + quote_n (0, cursor->header.name), + quote_n (1, volume_label_option))); + volno--; + global_volno--; + goto try_volume; + } + } + if (verbose_option) + fprintf (stdlis, _("Reading %s\n"), quote (cursor->header.name)); + cursor++; + } + else if (volume_label_option) + WARN ((0, 0, _("WARNING: No volume header"))); + + if (real_s_name) + { + uintmax_t s1, s2; + if (cursor->header.typeflag != GNUTYPE_MULTIVOL + || strcmp (cursor->header.name, real_s_name)) + { + WARN ((0, 0, _("%s is not continued on this volume"), + quote (real_s_name))); + volno--; + global_volno--; + goto try_volume; + } + s1 = UINTMAX_FROM_HEADER (cursor->header.size); + s2 = UINTMAX_FROM_HEADER (cursor->oldgnu_header.offset); + if (real_s_totsize != s1 + s2 || s1 + s2 < s2) + { + char totsizebuf[UINTMAX_STRSIZE_BOUND]; + char s1buf[UINTMAX_STRSIZE_BOUND]; + char s2buf[UINTMAX_STRSIZE_BOUND]; + + WARN ((0, 0, _("%s is the wrong size (%s != %s + %s)"), + quote (cursor->header.name), + STRINGIFY_BIGINT (save_totsize, totsizebuf), + STRINGIFY_BIGINT (s1, s1buf), + STRINGIFY_BIGINT (s2, s2buf))); + volno--; + global_volno--; + goto try_volume; + } + if (real_s_totsize - real_s_sizeleft + != OFF_FROM_HEADER (cursor->oldgnu_header.offset)) + { + WARN ((0, 0, _("This volume is out of sequence"))); + volno--; + global_volno--; + goto try_volume; + } + cursor++; + } + current_block = cursor; + records_read++; + return; + } + else if (status < 0) + { + archive_read_error (); + goto error_loop; /* try again */ + } + + short_read: + more = record_start->buffer + status; + left = record_size - status; + + while (left % BLOCKSIZE != 0 + || (left && status && read_full_records_option)) + { + if (status) + while ((status = rmtread (archive, more, left)) < 0) + archive_read_error (); + + if (status == 0) + break; + + if (! read_full_records_option) + FATAL_ERROR ((0, 0, _("Unaligned block (%lu bytes) in archive"), + (unsigned long) (record_size - left))); + + /* User warned us about this. Fix up. */ + + left -= status; + more += status; + } + + /* FIXME: for size=0, multi-volume support. On the first record, warn + about the problem. */ + + if (!read_full_records_option && verbose_option + && record_start_block == 0 && status > 0) + WARN ((0, 0, _("Record size = %lu blocks"), + (unsigned long) ((record_size - left) / BLOCKSIZE))); + + record_end = record_start + (record_size - left) / BLOCKSIZE; + records_read++; +} + +/* Flush the current buffer to/from the archive. */ +void +flush_archive (void) +{ + record_start_block += record_end - record_start; + current_block = record_start; + record_end = record_start + blocking_factor; + + if (access_mode == ACCESS_READ && time_to_start_writing) + { + access_mode = ACCESS_WRITE; + time_to_start_writing = 0; + + if (file_to_switch_to >= 0) + { + if (rmtclose (archive) != 0) + close_warn (*archive_name_cursor); + + archive = file_to_switch_to; + } + else + backspace_output (); + } + + switch (access_mode) + { + case ACCESS_READ: + flush_read (); + break; + + case ACCESS_WRITE: + flush_write (); + break; + + case ACCESS_UPDATE: + abort (); + } +} + +/* Backspace the archive descriptor by one record worth. If it's a + tape, MTIOCTOP will work. If it's something else, try to seek on + it. If we can't seek, we lose! */ +static void +backspace_output (void) +{ +#ifdef MTIOCTOP + { + struct mtop operation; + + operation.mt_op = MTBSR; + operation.mt_count = 1; + if (rmtioctl (archive, MTIOCTOP, (char *) &operation) >= 0) + return; + if (errno == EIO && rmtioctl (archive, MTIOCTOP, (char *) &operation) >= 0) + return; + } +#endif + + { + off_t position = rmtlseek (archive, (off_t) 0, SEEK_CUR); + + /* Seek back to the beginning of this record and start writing there. */ + + position -= record_size; + if (position < 0) + position = 0; + if (rmtlseek (archive, position, SEEK_SET) != position) + { + /* Lseek failed. Try a different method. */ + + WARN ((0, 0, + _("Cannot backspace archive file; it may be unreadable without -i"))); + + /* Replace the first part of the record with NULs. */ + + if (record_start->buffer != output_start) + memset (record_start->buffer, 0, + output_start - record_start->buffer); + } + } +} + +/* Close the archive file. */ +void +close_archive (void) +{ + if (time_to_start_writing || access_mode == ACCESS_WRITE) + flush_archive (); + +#if !MSDOS + + /* Manage to fully drain a pipe we might be reading, so to not break it on + the producer after the EOF block. FIXME: one of these days, GNU tar + might become clever enough to just stop working, once there is no more + work to do, we might have to revise this area in such time. */ + + if (access_mode == ACCESS_READ + && ! _isrmt (archive) + && (S_ISFIFO (archive_stat.st_mode) || S_ISSOCK (archive_stat.st_mode))) + while (rmtread (archive, record_start->buffer, record_size) > 0) + continue; +#endif + + if (verify_option) + verify_volume (); + + if (rmtclose (archive) != 0) + close_warn (*archive_name_cursor); + +#if !MSDOS + + if (child_pid) + { + int wait_status; + + while (waitpid (child_pid, &wait_status, 0) == -1) + if (errno != EINTR) + { + waitpid_error (use_compress_program_option); + break; + } + + if (WIFSIGNALED (wait_status)) + ERROR ((0, 0, _("Child died with signal %d"), + WTERMSIG (wait_status))); + else if (WEXITSTATUS (wait_status) != 0) + ERROR ((0, 0, _("Child returned status %d"), + WEXITSTATUS (wait_status))); + } +#endif /* !MSDOS */ + + if (current_file_name) + free (current_file_name); + if (current_link_name) + free (current_link_name); + if (save_name) + free (save_name); + if (real_s_name) + free (real_s_name); + free (multi_volume_option ? record_start - 2 : record_start); +} + +/* Called to initialize the global volume number. */ +void +init_volume_number (void) +{ + FILE *file = fopen (volno_file_option, "r"); + + if (file) + { + if (fscanf (file, "%d", &global_volno) != 1 + || global_volno < 0) + FATAL_ERROR ((0, 0, _("%s: contains invalid volume number"), + quotearg_colon (volno_file_option))); + if (ferror (file)) + read_error (volno_file_option); + if (fclose (file) != 0) + close_error (volno_file_option); + } + else if (errno != ENOENT) + open_error (volno_file_option); +} + +/* Called to write out the closing global volume number. */ +void +closeout_volume_number (void) +{ + FILE *file = fopen (volno_file_option, "w"); + + if (file) + { + fprintf (file, "%d\n", global_volno); + if (ferror (file)) + write_error (volno_file_option); + if (fclose (file) != 0) + close_error (volno_file_option); + } + else + open_error (volno_file_option); +} + +/* We've hit the end of the old volume. Close it and open the next one. + Return nonzero on success. */ +static int +new_volume (enum access_mode access) +{ + static FILE *read_file; + static int looped; + + if (!read_file && !info_script_option) + /* FIXME: if fopen is used, it will never be closed. */ + read_file = archive == STDIN_FILENO ? fopen (TTY_NAME, "r") : stdin; + + if (now_verifying) + return 0; + if (verify_option) + verify_volume (); + + if (rmtclose (archive) != 0) + close_warn (*archive_name_cursor); + + global_volno++; + if (global_volno < 0) + FATAL_ERROR ((0, 0, _("Volume number overflow"))); + volno++; + archive_name_cursor++; + if (archive_name_cursor == archive_name_array + archive_names) + { + archive_name_cursor = archive_name_array; + looped = 1; + } + + tryagain: + if (looped) + { + /* We have to prompt from now on. */ + + if (info_script_option) + { + if (volno_file_option) + closeout_volume_number (); + if (system (info_script_option) != 0) + FATAL_ERROR ((0, 0, _("`%s' command failed"), info_script_option)); + } + else + while (1) + { + char input_buffer[80]; + + fputc ('\007', stderr); + fprintf (stderr, + _("Prepare volume #%d for %s and hit return: "), + global_volno, quote (*archive_name_cursor)); + fflush (stderr); + + if (fgets (input_buffer, sizeof input_buffer, read_file) == 0) + { + WARN ((0, 0, _("EOF where user reply was expected"))); + + if (subcommand_option != EXTRACT_SUBCOMMAND + && subcommand_option != LIST_SUBCOMMAND + && subcommand_option != DIFF_SUBCOMMAND) + WARN ((0, 0, _("WARNING: Archive is incomplete"))); + + fatal_exit (); + } + if (input_buffer[0] == '\n' + || input_buffer[0] == 'y' + || input_buffer[0] == 'Y') + break; + + switch (input_buffer[0]) + { + case '?': + { + fprintf (stderr, _("\ + n [name] Give a new file name for the next (and subsequent) volume(s)\n\ + q Abort tar\n\ + ! Spawn a subshell\n\ + ? Print this list\n")); + } + break; + + case 'q': + /* Quit. */ + + WARN ((0, 0, _("No new volume; exiting.\n"))); + + if (subcommand_option != EXTRACT_SUBCOMMAND + && subcommand_option != LIST_SUBCOMMAND + && subcommand_option != DIFF_SUBCOMMAND) + WARN ((0, 0, _("WARNING: Archive is incomplete"))); + + fatal_exit (); + + case 'n': + /* Get new file name. */ + + { + char *name = &input_buffer[1]; + char *cursor; + + while (*name == ' ' || *name == '\t') + name++; + cursor = name; + while (*cursor && *cursor != '\n') + cursor++; + *cursor = '\0'; + + /* FIXME: the following allocation is never reclaimed. */ + *archive_name_cursor = xstrdup (name); + } + break; + + case '!': +#if MSDOS + spawnl (P_WAIT, getenv ("COMSPEC"), "-", 0); +#else /* not MSDOS */ + { + pid_t child; + const char *shell = getenv ("SHELL"); + if (! shell) + shell = "/bin/sh"; + child = xfork (); + if (child == 0) + { + execlp (shell, "-sh", "-i", 0); + exec_fatal (shell); + } + else + { + int wait_status; + while (waitpid (child, &wait_status, 0) == -1) + if (errno != EINTR) + { + waitpid_error (shell); + break; + } + } + } +#endif /* not MSDOS */ + break; + } + } + } + + if (verify_option) + archive = rmtopen (*archive_name_cursor, O_RDWR | O_CREAT, MODE_RW, + rsh_command_option); + else + switch (access) + { + case ACCESS_READ: + archive = rmtopen (*archive_name_cursor, O_RDONLY, MODE_RW, + rsh_command_option); + break; + + case ACCESS_WRITE: + if (backup_option) + maybe_backup_file (*archive_name_cursor, 1); + archive = rmtcreat (*archive_name_cursor, MODE_RW, + rsh_command_option); + break; + + case ACCESS_UPDATE: + archive = rmtopen (*archive_name_cursor, O_RDWR | O_CREAT, MODE_RW, + rsh_command_option); + break; + } + + if (archive < 0) + { + open_warn (*archive_name_cursor); + if (!verify_option && access == ACCESS_WRITE && backup_option) + undo_last_backup (); + goto tryagain; + } + +#if MSDOS + setmode (archive, O_BINARY); +#endif + + return 1; +} |
