*: tar-related cleanups: move struct to unarchive.h; move help to tar.c

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
diff --git a/archival/libunarchive/get_header_tar.c b/archival/libunarchive/get_header_tar.c
index fcddcb8..01c1043 100644
--- a/archival/libunarchive/get_header_tar.c
+++ b/archival/libunarchive/get_header_tar.c
@@ -118,34 +118,10 @@
 }
 #endif
 
-void BUG_tar_header_size(void);
 char FAST_FUNC get_header_tar(archive_handle_t *archive_handle)
 {
 	file_header_t *file_header = archive_handle->file_header;
-	struct {
-		/* ustar header, Posix 1003.1 */
-		char name[100];     /*   0-99 */
-		char mode[8];       /* 100-107 */
-		char uid[8];        /* 108-115 */
-		char gid[8];        /* 116-123 */
-		char size[12];      /* 124-135 */
-		char mtime[12];     /* 136-147 */
-		char chksum[8];     /* 148-155 */
-		char typeflag;      /* 156-156 */
-		char linkname[100]; /* 157-256 */
-		/* POSIX:   "ustar" NUL "00" */
-		/* GNU tar: "ustar  " NUL */
-		/* Normally it's defined as magic[6] followed by
-		 * version[2], but we put them together to simplify code
-		 */
-		char magic[8];      /* 257-264 */
-		char uname[32];     /* 265-296 */
-		char gname[32];     /* 297-328 */
-		char devmajor[8];   /* 329-336 */
-		char devminor[8];   /* 337-344 */
-		char prefix[155];   /* 345-499 */
-		char padding[12];   /* 500-512 */
-	} tar;
+	struct tar_header_t tar;
 	char *cp;
 	int i, sum_u, sum;
 #if ENABLE_FEATURE_TAR_OLDSUN_COMPATIBILITY
@@ -162,9 +138,6 @@
 # define p_linkname 0
 #endif
 
-	if (sizeof(tar) != 512)
-		BUG_tar_header_size();
-
 #if ENABLE_FEATURE_TAR_GNU_EXTENSIONS || ENABLE_FEATURE_TAR_SELINUX
  again:
 #endif
@@ -230,18 +203,21 @@
 		 * we can switch to get_header_tar_gz/bz2/lzma().
 		 * Needs seekable fd. I wish recv(MSG_PEEK) works
 		 * on any fd... */
-#if ENABLE_FEATURE_SEAMLESS_GZ
+# if ENABLE_FEATURE_SEAMLESS_GZ
 		if (tar.name[0] == 0x1f && tar.name[1] == (char)0x8b) { /* gzip */
 			get_header_ptr = get_header_tar_gz;
 		} else
-#endif
-#if ENABLE_FEATURE_SEAMLESS_BZ2
+# endif
+# if ENABLE_FEATURE_SEAMLESS_BZ2
 		if (tar.name[0] == 'B' && tar.name[1] == 'Z'
 		 && tar.name[2] == 'h' && isdigit(tar.name[3])
 		) { /* bzip2 */
 			get_header_ptr = get_header_tar_bz2;
 		} else
-#endif
+# endif
+# if ENABLE_FEATURE_SEAMLESS_XZ
+		//TODO
+# endif
 			goto err;
 		/* Two different causes for lseek() != 0:
 		 * unseekable fd (would like to support that too, but...),
diff --git a/archival/tar.c b/archival/tar.c
index 344c9de..f49fb12 100644
--- a/archival/tar.c
+++ b/archival/tar.c
@@ -48,37 +48,6 @@
 
 #if ENABLE_FEATURE_TAR_CREATE
 
-/* Tar file constants  */
-
-#define TAR_BLOCK_SIZE		512
-
-/* POSIX tar Header Block, from POSIX 1003.1-1990  */
-#define NAME_SIZE      100
-#define NAME_SIZE_STR "100"
-typedef struct TarHeader {       /* byte offset */
-	char name[NAME_SIZE];     /*   0-99 */
-	char mode[8];             /* 100-107 */
-	char uid[8];              /* 108-115 */
-	char gid[8];              /* 116-123 */
-	char size[12];            /* 124-135 */
-	char mtime[12];           /* 136-147 */
-	char chksum[8];           /* 148-155 */
-	char typeflag;            /* 156-156 */
-	char linkname[NAME_SIZE]; /* 157-256 */
-	/* POSIX:   "ustar" NUL "00" */
-	/* GNU tar: "ustar  " NUL */
-	/* Normally it's defined as magic[6] followed by
-	 * version[2], but we put them together to save code.
-	 */
-	char magic[8];            /* 257-264 */
-	char uname[32];           /* 265-296 */
-	char gname[32];           /* 297-328 */
-	char devmajor[8];         /* 329-336 */
-	char devminor[8];         /* 337-344 */
-	char prefix[155];         /* 345-499 */
-	char padding[12];         /* 500-512 (pad to exactly TAR_BLOCK_SIZE) */
-} TarHeader;
-
 /*
 ** writeTarFile(), writeFileToTarball(), and writeTarHeader() are
 ** the only functions that deal with the HardLinkInfo structure.
@@ -193,7 +162,7 @@
 }
 #define PUT_OCTAL(a, b) putOctal((a), sizeof(a), (b))
 
-static void chksum_and_xwrite(int fd, struct TarHeader* hp)
+static void chksum_and_xwrite(int fd, struct tar_header_t* hp)
 {
 	/* POSIX says that checksum is done on unsigned bytes
 	 * (Sun and HP-UX gets it wrong... more details in
@@ -235,7 +204,7 @@
 		"00000000000",
 		"00000000000",
 	};
-	struct TarHeader header;
+	struct tar_header_t header;
 	int size;
 
 	dir = !!dir; /* normalize: 0/1 */
@@ -262,17 +231,13 @@
 #endif
 
 /* Write out a tar header for the specified file/directory/whatever */
-void BUG_tar_header_size(void);
 static int writeTarHeader(struct TarBallInfo *tbInfo,
 		const char *header_name, const char *fileName, struct stat *statbuf)
 {
-	struct TarHeader header;
+	struct tar_header_t header;
 
-	if (sizeof(header) != 512)
-		BUG_tar_header_size();
-
-	memset(&header, 0, sizeof(struct TarHeader));
-
+	memset(&header, 0, sizeof(header));
+ 
 	strncpy(header.name, header_name, sizeof(header.name));
 
 	/* POSIX says to mask mode with 07777. */
@@ -738,6 +703,68 @@
 }
 #endif
 
+//usage:#define tar_trivial_usage
+//usage:       "-[" IF_FEATURE_TAR_CREATE("c") "xt" IF_FEATURE_SEAMLESS_GZ("z")
+//usage:	IF_FEATURE_SEAMLESS_BZ2("j") IF_FEATURE_SEAMLESS_LZMA("a")
+//usage:	IF_FEATURE_SEAMLESS_Z("Z") IF_FEATURE_TAR_NOPRESERVE_TIME("m") "vO] "
+//usage:	IF_FEATURE_TAR_FROM("[-X FILE] ")
+//usage:       "[-f TARFILE] [-C DIR] [FILE]..."
+//usage:#define tar_full_usage "\n\n"
+//usage:	IF_FEATURE_TAR_CREATE("Create, extract, ")
+//usage:	IF_NOT_FEATURE_TAR_CREATE("Extract ")
+//usage:	"or list files from a tar file\n"
+//usage:     "\nOperation:"
+//usage:	IF_FEATURE_TAR_CREATE(
+//usage:     "\n	c	Create"
+//usage:	)
+//usage:     "\n	x	Extract"
+//usage:     "\n	t	List"
+//usage:     "\nOptions:"
+//usage:     "\n	f	Name of TARFILE ('-' for stdin/out)"
+//usage:     "\n	C	Change to DIR before operation"
+//usage:     "\n	v	Verbose"
+//usage:	IF_FEATURE_SEAMLESS_GZ(
+//usage:     "\n	z	(De)compress using gzip"
+//usage:	)
+//usage:	IF_FEATURE_SEAMLESS_BZ2(
+//usage:     "\n	j	(De)compress using bzip2"
+//usage:	)
+//usage:	IF_FEATURE_SEAMLESS_LZMA(
+//usage:     "\n	a	(De)compress using lzma"
+//usage:	)
+//usage:	IF_FEATURE_SEAMLESS_Z(
+//usage:     "\n	Z	(De)compress using compress"
+//usage:	)
+//usage:     "\n	O	Extract to stdout"
+//usage:	IF_FEATURE_TAR_CREATE(
+//usage:     "\n	h	Follow symlinks"
+//usage:	)
+//usage:	IF_FEATURE_TAR_NOPRESERVE_TIME(
+//usage:     "\n	m	Don't restore mtime"
+//usage:	)
+//usage:	IF_FEATURE_TAR_FROM(
+//usage:	IF_FEATURE_TAR_LONG_OPTIONS(
+//usage:     "\n	exclude	File to exclude"
+//usage:	)
+//usage:     "\n	X	File with names to exclude"
+//usage:     "\n	T	File with names to include"
+//usage:	)
+//usage:
+//usage:#define tar_example_usage
+//usage:       "$ zcat /tmp/tarball.tar.gz | tar -xf -\n"
+//usage:       "$ tar -cf /tmp/tarball.tar /usr/local\n"
+
+// Supported but aren't in --help:
+//	o	no-same-owner
+//	p	same-permissions
+//	k	keep-old
+//	numeric-owner
+//	no-same-permissions
+//	overwrite
+//IF_FEATURE_TAR_TO_COMMAND(
+//	to-command
+//)
+
 enum {
 	OPTBIT_KEEP_OLD = 8,
 	IF_FEATURE_TAR_CREATE(   OPTBIT_CREATE      ,)
diff --git a/include/unarchive.h b/include/unarchive.h
index f3aa05d..b4cf160 100644
--- a/include/unarchive.h
+++ b/include/unarchive.h
@@ -113,6 +113,39 @@
 #define ARCHIVE_O_TRUNC             (1 << 8)
 
 
+/* POSIX tar Header Block, from POSIX 1003.1-1990  */
+#define TAR_BLOCK_SIZE 512
+#define NAME_SIZE      100
+#define NAME_SIZE_STR "100"
+typedef struct tar_header_t {       /* byte offset */
+	char name[NAME_SIZE];     /*   0-99 */
+	char mode[8];             /* 100-107 */
+	char uid[8];              /* 108-115 */
+	char gid[8];              /* 116-123 */
+	char size[12];            /* 124-135 */
+	char mtime[12];           /* 136-147 */
+	char chksum[8];           /* 148-155 */
+	char typeflag;            /* 156-156 */
+	char linkname[NAME_SIZE]; /* 157-256 */
+	/* POSIX:   "ustar" NUL "00" */
+	/* GNU tar: "ustar  " NUL */
+	/* Normally it's defined as magic[6] followed by
+	 * version[2], but we put them together to save code.
+	 */
+	char magic[8];            /* 257-264 */
+	char uname[32];           /* 265-296 */
+	char gname[32];           /* 297-328 */
+	char devmajor[8];         /* 329-336 */
+	char devminor[8];         /* 337-344 */
+	char prefix[155];         /* 345-499 */
+	char padding[12];         /* 500-512 (pad to exactly TAR_BLOCK_SIZE) */
+} tar_header_t;
+struct BUG_tar_header {
+	char c[sizeof(tar_header_t) == TAR_BLOCK_SIZE ? 1 : -1];
+};
+
+
+
 /* Info struct unpackers can fill out to inform users of thing like
  * timestamps of unpacked files */
 typedef struct unpack_info_t {
diff --git a/include/usage.src.h b/include/usage.src.h
index f30edbc..f84bb93 100644
--- a/include/usage.src.h
+++ b/include/usage.src.h
@@ -4273,54 +4273,6 @@
 #define tac_full_usage "\n\n" \
 	"Concatenate FILEs and print them in reverse"
 
-#define tar_trivial_usage \
-       "-[" IF_FEATURE_TAR_CREATE("c") "xt" IF_FEATURE_SEAMLESS_GZ("z") \
-	IF_FEATURE_SEAMLESS_BZ2("j") IF_FEATURE_SEAMLESS_LZMA("a") \
-	IF_FEATURE_SEAMLESS_Z("Z") IF_FEATURE_TAR_NOPRESERVE_TIME("m") "vO] " \
-	IF_FEATURE_TAR_FROM("[-X FILE] ") \
-       "[-f TARFILE] [-C DIR] [FILE]..."
-#define tar_full_usage "\n\n" \
-	IF_FEATURE_TAR_CREATE("Create, extract, ") \
-	IF_NOT_FEATURE_TAR_CREATE("Extract ") \
-       "or list files from a tar file\n" \
-     "\nOptions:" \
-	IF_FEATURE_TAR_CREATE( \
-     "\n	c	Create" \
-	) \
-     "\n	x	Extract" \
-     "\n	t	List" \
-     "\nArchive format selection:" \
-	IF_FEATURE_SEAMLESS_GZ( \
-     "\n	z	Filter the archive through gzip" \
-	) \
-	IF_FEATURE_SEAMLESS_BZ2( \
-     "\n	j	Filter the archive through bzip2" \
-	) \
-	IF_FEATURE_SEAMLESS_LZMA( \
-     "\n	a	Filter the archive through lzma" \
-	) \
-	IF_FEATURE_SEAMLESS_Z( \
-     "\n	Z	Filter the archive through compress" \
-	) \
-	IF_FEATURE_TAR_NOPRESERVE_TIME( \
-     "\n	m	Do not restore mtime" \
-	) \
-     "\nFile selection:" \
-     "\n	f	Name of TARFILE or \"-\" for stdin" \
-     "\n	O	Extract to stdout" \
-	IF_FEATURE_TAR_FROM( \
-	IF_FEATURE_TAR_LONG_OPTIONS( \
-     "\n	exclude	File to exclude" \
-	) \
-     "\n	X	File with names to exclude" \
-	) \
-     "\n	C	Change to DIR before operation" \
-     "\n	v	Verbose" \
-
-#define tar_example_usage \
-       "$ zcat /tmp/tarball.tar.gz | tar -xf -\n" \
-       "$ tar -cf /tmp/tarball.tar /usr/local\n"
-
 #define taskset_trivial_usage \
        "[-p] [MASK] [PID | PROG ARGS]"
 #define taskset_full_usage "\n\n" \
diff --git a/procps/smemcap.c b/procps/smemcap.c
index cdcc891..06cf93c 100644
--- a/procps/smemcap.c
+++ b/procps/smemcap.c
@@ -20,42 +20,19 @@
 //config:	  a memory usage statistic tool.
 
 #include "libbb.h"
-
-struct tar_header {
-	char name[100];           /*   0-99 */
-	char mode[8];             /* 100-107 */
-	char uid[8];              /* 108-115 */
-	char gid[8];              /* 116-123 */
-	char size[12];            /* 124-135 */
-	char mtime[12];           /* 136-147 */
-	char chksum[8];           /* 148-155 */
-	char typeflag;            /* 156-156 */
-	char linkname[100];       /* 157-256 */
-	/* POSIX:   "ustar" NUL "00" */
-	/* GNU tar: "ustar  " NUL */
-	/* Normally it's defined as magic[6] followed by
-	 * version[2], but we put them together to save code.
-	 */
-	char magic[8];            /* 257-264 */
-	char uname[32];           /* 265-296 */
-	char gname[32];           /* 297-328 */
-	char devmajor[8];         /* 329-336 */
-	char devminor[8];         /* 337-344 */
-	char prefix[155];         /* 345-499 */
-	char padding[12];         /* 500-512 (pad to exactly TAR_512) */
-};
+#include "unarchive.h"
 
 struct fileblock {
 	struct fileblock *next;
-	char data[512];
+	char data[TAR_BLOCK_SIZE];
 };
 
 static void writeheader(const char *path, struct stat *sb, int type)
 {
-	struct tar_header header;
+	struct tar_header_t header;
 	int i, sum;
 
-	memset(&header, 0, 512);
+	memset(&header, 0, TAR_BLOCK_SIZE);
 	strcpy(header.name, path);
 	sprintf(header.mode, "%o", sb->st_mode & 0777);
 	/* careful to not overflow fields! */
@@ -73,11 +50,11 @@
 	 * digits, followed by a NUL like the other fields... */
 	header.chksum[7] = ' ';
 	sum = ' ' * 7;
-	for (i = 0; i < 512; i++)
+	for (i = 0; i < TAR_BLOCK_SIZE; i++)
 		sum += ((unsigned char*)&header)[i];
 	sprintf(header.chksum, "%06o", sum);
 
-	xwrite(STDOUT_FILENO, &header, 512);
+	xwrite(STDOUT_FILENO, &header, TAR_BLOCK_SIZE);
 }
 
 static void archivefile(const char *path)
@@ -94,10 +71,10 @@
 		cur = xzalloc(sizeof(*cur));
 		*prev = cur;
 		prev = &cur->next;
-		r = full_read(fd, cur->data, 512);
+		r = full_read(fd, cur->data, TAR_BLOCK_SIZE);
 		if (r > 0)
 			size += r;
-	} while (r == 512);
+	} while (r == TAR_BLOCK_SIZE);
 
 	/* write archive header */
 	fstat(fd, &s);
@@ -106,8 +83,8 @@
 	writeheader(path, &s, '0');
 
 	/* dump file contents */
-	for (cur = start; (int)size > 0; size -= 512) {
-		xwrite(STDOUT_FILENO, cur->data, 512);
+	for (cur = start; (int)size > 0; size -= TAR_BLOCK_SIZE) {
+		xwrite(STDOUT_FILENO, cur->data, TAR_BLOCK_SIZE);
 		start = cur;
 		cur = cur->next;
 		free(start);