Portability: Support platforms that lack (struct stat).st_blksize or SSIZE_MAX

Of course, FreeBSD has both.

lib/libarchive/archive_platform.h

@@ -78,6 +78,9 @@
 #if !HAVE_DECL_SIZE_MAX
 #define	SIZE_MAX (~(size_t)0)
 #endif
+#if !HAVE_DECL_SSIZE_MAX
+#define	SSIZE_MAX ((ssize_t)(SIZE_MAX >> 1))
+#endif
 #if !HAVE_DECL_UINT32_MAX
 #define	UINT32_MAX (~(uint32_t)0)
 #endif

lib/libarchive/archive_write_disk.c

@@ -514,9 +514,15 @@ write_data_block(struct archive_write_disk *a,
 	}
 
 	if (a->flags & ARCHIVE_EXTRACT_SPARSE) {
+#if HAVE_STRUCT_STAT_ST_BLKSIZE
 		if ((r = _archive_write_disk_lazy_stat(a)) != ARCHIVE_OK)
 			return (r);
 		block_size = a->pst->st_blksize;
+#else
+		/* XXX TODO XXX Is there a more appropriate choice here ? */
+		/* This needn't match the filesystem allocation size. */
+		block_size = 16*1024;
+#endif
 	}
 
 	if (a->filesize >= 0 && (off_t)(offset + size) > a->filesize)

lib/libarchive/config_freebsd.h

@@ -41,6 +41,7 @@
 #define	HAVE_DECL_INT64_MAX 1
 #define	HAVE_DECL_INT64_MIN 1
 #define	HAVE_DECL_SIZE_MAX 1
+#define	HAVE_DECL_SSIZE_MAX 1
 #define	HAVE_DECL_STRERROR_R 1
 #define	HAVE_DECL_UINT32_MAX 1
 #define	HAVE_DECL_UINT64_MAX 1
@@ -86,6 +87,7 @@
 #define	HAVE_STRINGS_H 1
 #define	HAVE_STRING_H 1
 #define	HAVE_STRRCHR 1
+#define	HAVE_STRUCT_STAT_ST_BLKSIZE 1
 #define	HAVE_STRUCT_STAT_ST_MTIMESPEC_TV_NSEC 1
 #define	HAVE_SYS_ACL_H 1
 #define	HAVE_SYS_IOCTL_H 1