uuUndo/uundo13.c

/*
 * uundo.c: extract a multi-part uuencoded archive               Version 1.3a
 * written by Aaron Giles                                           03/08/92
 * 
 * usage:
 *   uundo [-hLloqv] file1 [file2 [...]]
 *   uundo [-hLloqv] < file
 *
 * options:
 *   -h  header: write the article header of the earliest part to target.hdr
 *   -L  lower all: convert all characters in all filenames to lower case
 *   -l  lower: convert only all-upper-case filenames to lower case
 *   -o  overwrite: automatically overwrite existing files without permission
 *   -q  query: allow overwriting of existing files, but ask permission first
 *   -v  verbose: display part numbers and status info
 *
 * special features:
 *   - does not require all parts to be in order*
 *   - attempts to identify missing parts*
 *   - works on uuencoded files included in shar archives
 *   - can accept either single or multiple files on the command line
 *   - can accept stream input from stdin
 * (* requires part numbering informating in the subject line of each part)
 *
 * bugs/requests/modifications to:
 *   a-giles@uchicago.edu     -or-
 *   gile@midway.uchicago.edu -or-
 *   giles@hep.uchicago.edu
 *
 * philosophy:
 *   I will try my best to keep up with any bug reports (first priority) or
 *   new feature requests.  Note that my primary goal is robustness, so that
 *   requests which would overly complicate things or result in "flaky" code
 *   will very likely not be put in.
 *
 * copyright control:
 *   This program is public domain, though copyrighted (c) 1992 by its
 *   author, Aaron Giles.  If you wish to distribute modified copies of
 *   this program, please contact the author first.
 *
 * standard disclaimer:
 *   Use this program at your own risk.  The author takes no responsibility
 *   for any loss of data or damage that results from using this program.
 *
 * known problems/limitations:
 *   - cannot handle multiple target files in the same input file (sorry!)
 *   - can't yet accept input piped from rn or trn
 *
 * to be added in future versions:
 *   - support for saving header information
 *   - support for piping, allowing use with rn/trn
 *
 * version history:
 *   1.0 (2/11/92) - initial release
 *   1.1 (2/13/92) - added stdin support for preliminary use with rn
 *                   no longer so restrictive on the first line of each part
 *                   added verbose option
 *                   added a warning to overwrite existing files
 *                   added an option to turn off this warning
 *                   now attempts to make file writeable before overwriting
 *                   fixed problem with "BEGIN..." lines fooling the decoder
 *   1.2 (2/21/92) - added force lowercase options
 *                   changed procedure dealing with conflicting filenames
 *                   added query option
 *                   now uses process ID in temporary names to avoid conflicts
 *                   output directory can be set via UUNDO environment variable
 *  1.21 (2/28/92) - fixed bug that would alter directory attributes if none
 *                      of the input files were found 
 *   1.3 (3/08/92) - added support for maximum filename length
 *                 - refined handling of jumbled and unlabelled parts
 *                 - fixed the aforementioned bug -- again
 *                 - added option to write header of earliest part to a file
 */

#include <ctype.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/types.h>
#include <unistd.h>

/*
 * Platform-specific definitions
 */
#define PATHSEP '/'               /* path separator character */
#define MAXNAMELEN 32             /* maximum length of a given filename */
#define TEMPNAME "/usr/tmp/uu"    /* prefix for temporary files */

/*
 * Arbitrary global definitions
 */
#define MAXLEN 256                /* maximum length of strings/pathnames */
#define MAXPARTS 256              /* maximum number of parts in file */
#define BUFSIZE 32768             /* size of temporary buffer */

/*
 * Header storage structure
 */
typedef struct he