tar.c

这是一个SIGMA方案的PMP播放器的UCLINUX程序,可播放DVD,VCD,CD MP3...有很好的参考价值.

	}

	/* It is a bad idea to store the archive we are in the process of creating,
	 * so check the device and inode to be sure that this particular file isn't
	 * the new tarball */
	if (tbInfo->statBuf.st_dev == statbuf->st_dev &&
			tbInfo->statBuf.st_ino == statbuf->st_ino) {
		error_msg("%s: file is the archive; skipping", fileName);
		return( TRUE);
	}

	header_name = fileName;
	while (header_name[0] == '/') {
		static int alreadyWarned=FALSE;
		if (alreadyWarned==FALSE) {
			error_msg("Removing leading '/' from member names");
			alreadyWarned=TRUE;
		}
		header_name++;
	}

	if (strlen(fileName) >= NAME_SIZE) {
		error_msg(name_longer_than_foo, NAME_SIZE);
		return ( TRUE);
	}

	if (header_name[0] == '\0')
		return TRUE;

# if defined CONFIG_FEATURE_TAR_EXCLUDE
	if (exclude_file(tbInfo->excludeList, header_name)) {
		return SKIP;
	}
# endif //CONFIG_FEATURE_TAR_EXCLUDE

	if (writeTarHeader(tbInfo, header_name, fileName, statbuf)==FALSE) {
		return( FALSE);
	} 

	/* Now, if the file is a regular file, copy it out to the tarball */
	if ((tbInfo->hlInfo == NULL)
	&&  (S_ISREG(statbuf->st_mode))) {
		int  inputFileFd;
		char buffer[BUFSIZ];
		ssize_t size=0, readSize=0;

		/* open the file we want to archive, and make sure all is well */
		if ((inputFileFd = open(fileName, O_RDONLY)) < 0) {
			error_msg("%s: Cannot open: %s", fileName, strerror(errno));
			return( FALSE);
		}
		
		/* write the file to the archive */
		while ( (size = full_read(inputFileFd, buffer, sizeof(buffer))) > 0 ) {
			if (full_write(tbInfo->tarFd, buffer, size) != size ) {
				/* Output file seems to have a problem */
				error_msg(io_error, fileName, strerror(errno)); 
				return( FALSE);
			}
			readSize+=size;
		}
		if (size == -1) {
			error_msg(io_error, fileName, strerror(errno)); 
			return( FALSE);
		}
		/* Pad the file up to the tar block size */
		for (; (readSize%TAR_BLOCK_SIZE) != 0; readSize++) {
			write(tbInfo->tarFd, "\0", 1);
		}
		close( inputFileFd);
	}

	return( TRUE);
}

static int writeTarFile(const char* tarName, int verboseFlag, char **argv,
		char** excludeList)
{
	int tarFd=-1;
	int errorFlag=FALSE;
	ssize_t size;
	struct TarBallInfo tbInfo;
	tbInfo.verboseFlag = verboseFlag;
	tbInfo.hlInfoHead = NULL;

	/* Make sure there is at least one file to tar up.  */
	if (*argv == NULL)
		error_msg_and_die("Cowardly refusing to create an empty archive");

	/* Open the tar file for writing.  */
	if (tarName == NULL)
		tbInfo.tarFd = fileno(stdout);
	else
		tbInfo.tarFd = open (tarName, O_WRONLY | O_CREAT | O_TRUNC, 0644);
	if (tbInfo.tarFd < 0) {
		perror_msg( "Error opening '%s'", tarName);
		freeHardLinkInfo(&tbInfo.hlInfoHead);
		return ( FALSE);
	}
	tbInfo.excludeList=excludeList;
	/* Store the stat info for the tarball's file, so
	 * can avoid including the tarball into itself....  */
	if (fstat(tbInfo.tarFd, &tbInfo.statBuf) < 0)
		error_msg_and_die(io_error, tarName, strerror(errno)); 

	/* Read the directory/files and iterate over them one at a time */
	while (*argv != NULL) {
		if (! recursive_action(*argv++, TRUE, FALSE, FALSE,
					writeFileToTarball, writeFileToTarball, 
					(void*) &tbInfo)) {
			errorFlag = TRUE;
		}
	}
	/* Write two empty blocks to the end of the archive */
	for (size=0; size<(2*TAR_BLOCK_SIZE); size++) {
		write(tbInfo.tarFd, "\0", 1);
	}

	/* To be pedantically correct, we would check if the tarball
	 * is smaller than 20 tar blocks, and pad it if it was smaller,
	 * but that isn't necessary for GNU tar interoperability, and
	 * so is considered a waste of space */

	/* Hang up the tools, close up shop, head home */
	close(tarFd);
	if (errorFlag) {
		error_msg("Error exit delayed from previous errors");
		freeHardLinkInfo(&tbInfo.hlInfoHead);
		return(FALSE);
	}
	freeHardLinkInfo(&tbInfo.hlInfoHead);
	return( TRUE);
}
#endif //tar_create

void append_file_to_list(const char *new_name, char ***list, int *list_count)
{
	*list = realloc(*list, sizeof(char *) * (*list_count + 2));
	(*list)[*list_count] = xstrdup(new_name);
	(*list_count)++;
	(*list)[*list_count] = NULL;
}

void append_file_list_to_list(char *filename, char ***name_list, int *num_of_entries)
{
	FILE *src_stream;
	char *line;
	
	src_stream = xfopen(filename, "r");
	while ((line = get_line_from_file(src_stream)) != NULL) {
		chomp (line);
		append_file_to_list(line, name_list, num_of_entries);
		free(line);
	}
	fclose(src_stream);
}

#ifdef CONFIG_FEATURE_TAR_EXCLUDE
/*
 * Create a list of names that are in the include list AND NOT in the exclude lists
 */
char **list_and_not_list(char **include_list, char **exclude_list)
{
	char **new_include_list = NULL;
	int new_include_count = 0;
	int include_count = 0;
	int exclude_count;

	if (include_list == NULL) {
		return(NULL);
	}
	
	while (include_list[include_count] != NULL) {
		int found = FALSE;
		exclude_count = 0;
		while (exclude_list[exclude_count] != NULL) {
			if (strcmp(include_list[include_count], exclude_list[exclude_count]) == 0) {
				found = TRUE;
				break;
			}
			exclude_count++;
		}

		if (! found) {
			new_include_list = realloc(new_include_list, sizeof(char *) * (include_count + 2));
			new_include_list[new_include_count] = include_list[include_count];
			new_include_count++;
		} else {
			free(include_list[include_count]);
		}
		include_count++;
	}
	new_include_list[new_include_count] = NULL;
	return(new_include_list);
}
#endif

int tar_main(int argc, char **argv)
{
	enum untar_funct_e {
		/* This is optional */
		untar_unzip = 1,
		/* Require one and only one of these */
		untar_list = 2,
		untar_create = 4,
		untar_extract = 8
	};

	FILE *src_stream = NULL;
	FILE *uncompressed_stream = NULL;
	char **include_list = NULL;
	char **exclude_list = NULL;
	char *src_filename = NULL;
	char *dst_prefix = NULL;
	int opt;
	unsigned short untar_funct = 0;
	unsigned short untar_funct_required = 0;
	unsigned short extract_function = 0;
	int include_list_count = 0;
#ifdef CONFIG_FEATURE_TAR_EXCLUDE
	int exclude_list_count = 0;
#endif
#ifdef CONFIG_FEATURE_TAR_GZIP
	int gunzip_pid;
	int gz_fd = 0;
#endif

	if (argc < 2) {
		show_usage();
	}

	/* Prepend '-' to the first argument if required */
	if (argv[1][0] != '-') {
		char *tmp = xmalloc(strlen(argv[1]) + 2);
		tmp[0] = '-';
		strcpy(tmp + 1, argv[1]);
		argv[1] = tmp;
	}

	while ((opt = getopt(argc, argv, "ctxT:X:C:f:Opvz")) != -1) {
		switch (opt) {

		/* One and only one of these is required */
		case 'c':
			untar_funct_required |= untar_create;
			break;
		case 't':
			untar_funct_required |= untar_list;
			extract_function |= extract_list |extract_unconditional;
			break;
		case 'x':
			untar_funct_required |= untar_extract;
			extract_function |= (extract_all_to_fs | extract_unconditional | extract_create_leading_dirs);
			break;

		/* These are optional */
		/* Exclude or Include files listed in <filename>*/
#ifdef CONFIG_FEATURE_TAR_EXCLUDE
		case 'X':
			append_file_list_to_list(optarg, &exclude_list, &exclude_list_count);
			break;
#endif
		case 'T':
			// by default a list is an include list
			append_file_list_to_list(optarg, &include_list, &include_list_count);
			break;

		case 'C':	// Change to dir <optarg>
			/* Make sure dst_prefix ends in a '/' */
			dst_prefix = concat_path_file(optarg, "/");
			break;
		case 'f':	// archive filename
			if (strcmp(optarg, "-") == 0) {
				src_filename = NULL;
			} else {
				src_filename = xstrdup(optarg);
			}
			break;
		case 'O':
			extract_function |= extract_to_stdout;
			break;
		case 'p':
			break;
		case 'v':
			if (extract_function & extract_list) {
				extract_function |= extract_verbose_list;
			}
			extract_function |= extract_list;
			break;
#ifdef CONFIG_FEATURE_TAR_GZIP
		case 'z':
			untar_funct |= untar_unzip;
			break;
#endif
		default:
			show_usage();
		}
	}

	/* Make sure the valid arguments were passed */
	if (untar_funct_required == 0) {
		error_msg_and_die("You must specify one of the `-ctx' options");
	}
	if ((untar_funct_required != untar_create) && 
			(untar_funct_required != untar_extract) &&
			(untar_funct_required != untar_list)) {
		error_msg_and_die("You may not specify more than one `ctx' option.");
	}
	untar_funct |= untar_funct_required;

	/* Setup an array of filenames to work with */
	while (optind < argc) {
		append_file_to_list(argv[optind], &include_list, &include_list_count);
		optind++;
	}
	if (extract_function & (extract_list | extract_all_to_fs)) {
		if (dst_prefix == NULL) {
			dst_prefix = xstrdup("./");
		}

		/* Setup the source of the tar data */
		if (src_filename != NULL) {
			src_stream = xfopen(src_filename, "r");
		} else {
			src_stream = stdin;
		}
#ifdef CONFIG_FEATURE_TAR_GZIP
		/* Get a binary tree of all the tar file headers */
		if (untar_funct & untar_unzip) {
			uncompressed_stream = gz_open(src_stream, &gunzip_pid);
		} else
#endif // CONFIG_FEATURE_TAR_GZIP
			uncompressed_stream = src_stream;
		
		/* extract or list archive */
		unarchive(uncompressed_stream, stdout, &get_header_tar, extract_function, dst_prefix, include_list, exclude_list);
		fclose(uncompressed_stream);
	}
#ifdef CONFIG_FEATURE_TAR_CREATE
	/* create an archive */
	else if (untar_funct & untar_create) {
		int verboseFlag = FALSE;

#ifdef CONFIG_FEATURE_TAR_GZIP
		if (untar_funct & untar_unzip) {
			error_msg_and_die("Creation of compressed tarfile not internally support by tar, pipe to busybox gunzip");
		}
#endif // CONFIG_FEATURE_TAR_GZIP
		if (extract_function & extract_verbose_list) {
			verboseFlag = TRUE;
		}
		writeTarFile(src_filename, verboseFlag, include_list, exclude_list);
	}
#endif // CONFIG_FEATURE_TAR_CREATE

	/* Cleanups */
#ifdef CONFIG_FEATURE_TAR_GZIP
	if (untar_funct & untar_unzip) {
		fclose(src_stream);
		close(gz_fd);
		gz_close(gunzip_pid);
	}
#endif // CONFIG_FEATURE_TAR_GZIP
#ifdef CONFIG_FEATURE_CLEAN_UP
	if (src_filename) {
		free(src_filename);
	}
#endif
	return(EXIT_SUCCESS);
}