MfP4: Handle entries with unset size properly: Regular files with

unspecified size are "unlimited" (required by Zip reader, which
sometimes does not know the uncompressed size of an entry until it
gets to the end).  Also, hardlinks with unspecified (or zero) size do
not overwrite the data on disk nor do they set metadata.  This is
compatible with GNU tar and NetBSD pax behavior.

1 files changed, 72 insertions, 15 deletions

diff --git a/lib/libarchive/test/test_write_disk_hardlink.c b/lib/libarchive/test/test_write_disk_hardlink.c
index f8197c8..6e38d86 100644
--- a/lib/libarchive/test/test_write_disk_hardlink.c
+++ b/lib/libarchive/test/test_write_disk_hardlink.c
@@ -61,18 +61,48 @@ DEFINE_TEST(test_write_disk_hardlink)
 	archive_entry_set_mode(ae, S_IFREG | 0755);
 	archive_entry_set_size(ae, sizeof(data));
 	assertEqualIntA(ad, 0, archive_write_header(ad, ae));
-	assertEqualInt(sizeof(data), archive_write_data(ad, data, sizeof(data)));
+	assertEqualInt(sizeof(data),
+	    archive_write_data(ad, data, sizeof(data)));
 	assertEqualIntA(ad, 0, archive_write_finish_entry(ad));
 	archive_entry_free(ae);
 
-	/* Link. */
+	/* Link.  Size of zero means this doesn't carry data. */
 	assert((ae = archive_entry_new()) != NULL);
 	archive_entry_copy_pathname(ae, "link1b");
-	archive_entry_set_mode(ae, S_IFREG | 0600);
+	archive_entry_set_mode(ae, S_IFREG | 0642);
 	archive_entry_set_size(ae, 0);
 	archive_entry_copy_hardlink(ae, "link1a");
 	assertEqualIntA(ad, 0, archive_write_header(ad, ae));
-	assertEqualInt(0, archive_write_data(ad, data, sizeof(data)));
+	assertEqualInt(ARCHIVE_WARN,
+	    archive_write_data(ad, data, sizeof(data)));
+	assertEqualIntA(ad, 0, archive_write_finish_entry(ad));
+	archive_entry_free(ae);
+
+	/*
+	 * Repeat tar approach test, but use unset to mark the
+	 * hardlink as having no data.
+	 */
+
+	/* Regular file. */
+	assert((ae = archive_entry_new()) != NULL);
+	archive_entry_copy_pathname(ae, "link2a");
+	archive_entry_set_mode(ae, S_IFREG | 0755);
+	archive_entry_set_size(ae, sizeof(data));
+	assertEqualIntA(ad, 0, archive_write_header(ad, ae));
+	assertEqualInt(sizeof(data),
+	    archive_write_data(ad, data, sizeof(data)));
+	assertEqualIntA(ad, 0, archive_write_finish_entry(ad));
+	archive_entry_free(ae);
+
+	/* Link.  Unset size means this doesn't carry data. */
+	assert((ae = archive_entry_new()) != NULL);
+	archive_entry_copy_pathname(ae, "link2b");
+	archive_entry_set_mode(ae, S_IFREG | 0642);
+	archive_entry_unset_size(ae);
+	archive_entry_copy_hardlink(ae, "link2a");
+	assertEqualIntA(ad, 0, archive_write_header(ad, ae));
+	assertEqualInt(ARCHIVE_WARN,
+	    archive_write_data(ad, data, sizeof(data)));
 	assertEqualIntA(ad, 0, archive_write_finish_entry(ad));
 	archive_entry_free(ae);
 
@@ -83,7 +113,7 @@ DEFINE_TEST(test_write_disk_hardlink)
 
 	/* Regular file. */
 	assert((ae = archive_entry_new()) != NULL);
-	archive_entry_copy_pathname(ae, "link2a");
+	archive_entry_copy_pathname(ae, "link3a");
 	archive_entry_set_mode(ae, S_IFREG | 0600);
 	archive_entry_set_size(ae, sizeof(data));
 	assertEqualIntA(ad, 0, archive_write_header(ad, ae));
@@ -93,10 +123,10 @@ DEFINE_TEST(test_write_disk_hardlink)
 
 	/* Link. */
 	assert((ae = archive_entry_new()) != NULL);
-	archive_entry_copy_pathname(ae, "link2b");
+	archive_entry_copy_pathname(ae, "link3b");
 	archive_entry_set_mode(ae, S_IFREG | 0755);
 	archive_entry_set_size(ae, sizeof(data));
-	archive_entry_copy_hardlink(ae, "link2a");
+	archive_entry_copy_hardlink(ae, "link3a");
 	assertEqualIntA(ad, 0, archive_write_header(ad, ae));
 	assertEqualInt(sizeof(data), archive_write_data(ad, data, sizeof(data)));
 	assertEqualIntA(ad, 0, archive_write_finish_entry(ad));
@@ -109,7 +139,7 @@ DEFINE_TEST(test_write_disk_hardlink)
 
 	/* Regular file. */
 	assert((ae = archive_entry_new()) != NULL);
-	archive_entry_copy_pathname(ae, "link3a");
+	archive_entry_copy_pathname(ae, "link4a");
 	archive_entry_set_mode(ae, S_IFREG | 0600);
 	archive_entry_set_size(ae, 0);
 	assertEqualIntA(ad, 0, archive_write_header(ad, ae));
@@ -123,10 +153,10 @@ DEFINE_TEST(test_write_disk_hardlink)
 
 	/* Link. */
 	assert((ae = archive_entry_new()) != NULL);
-	archive_entry_copy_pathname(ae, "link3b");
+	archive_entry_copy_pathname(ae, "link4b");
 	archive_entry_set_mode(ae, S_IFREG | 0755);
 	archive_entry_set_size(ae, sizeof(data));
-	archive_entry_copy_hardlink(ae, "link3a");
+	archive_entry_copy_hardlink(ae, "link4a");
 	assertEqualIntA(ad, 0, archive_write_header(ad, ae));
 	assertEqualInt(sizeof(data), archive_write_data(ad, data, sizeof(data)));
 	assertEqualIntA(ad, 0, archive_write_finish_entry(ad));
@@ -138,36 +168,63 @@ DEFINE_TEST(test_write_disk_hardlink)
 #endif
 
 	/* Test the entries on disk. */
+
+	/* Test #1 */
 	assert(0 == stat("link1a", &st));
+	/* If the hardlink was successfully created and the archive
+	 * doesn't carry data for it, we consider it to be
+	 * non-authoritive for meta data as well.  This is consistent
+	 * with GNU tar and BSD pax.  */
 	assertEqualInt(st.st_mode, (S_IFREG | 0755) & ~UMASK);
 	assertEqualInt(st.st_size, sizeof(data));
 	assertEqualInt(st.st_nlink, 2);
 
 	assert(0 == stat("link1b", &st2));
-	assertEqualInt(st2.st_mode, (S_IFREG | 0755) & ~UMASK);
-	assertEqualInt(st2.st_size, sizeof(data));
-	assertEqualInt(st2.st_nlink, 2);
+	assertEqualInt(st.st_mode, st2.st_mode);
+	assertEqualInt(st.st_size, st2.st_size);
+	assertEqualInt(st.st_nlink, st2.st_nlink);
 	assertEqualInt(st.st_ino, st2.st_ino);
 	assertEqualInt(st.st_dev, st2.st_dev);
 
+	/* Test #2: Should produce identical results to test #1 */
+	/* Note that marking a hardlink with size = 0 is treated the
+	 * same as having an unset size.  This is partly for backwards
+	 * compatibility (we used to not have unset tracking, so
+	 * relied on size == 0) and partly to match the model used by
+	 * common file formats that store a size of zero for
+	 * hardlinks. */
 	assert(0 == stat("link2a", &st));
 	assertEqualInt(st.st_mode, (S_IFREG | 0755) & ~UMASK);
 	assertEqualInt(st.st_size, sizeof(data));
 	assertEqualInt(st.st_nlink, 2);
 
 	assert(0 == stat("link2b", &st2));
+	assertEqualInt(st.st_mode, st2.st_mode);
+	assertEqualInt(st.st_size, st2.st_size);
+	assertEqualInt(st.st_nlink, st2.st_nlink);
+	assertEqualInt(st.st_ino, st2.st_ino);
+	assertEqualInt(st.st_dev, st2.st_dev);
+
+	/* Test #3 */
+	assert(0 == stat("link3a", &st));
+	assertEqualInt(st.st_mode, (S_IFREG | 0755) & ~UMASK);
+	assertEqualInt(st.st_size, sizeof(data));
+	assertEqualInt(st.st_nlink, 2);
+
+	assert(0 == stat("link3b", &st2));
 	assertEqualInt(st2.st_mode, (S_IFREG | 0755) & ~UMASK);
 	assertEqualInt(st2.st_size, sizeof(data));
 	assertEqualInt(st2.st_nlink, 2);
 	assertEqualInt(st.st_ino, st2.st_ino);
 	assertEqualInt(st.st_dev, st2.st_dev);
 
-	assert(0 == stat("link3a", &st));
+	/* Test #4 */
+	assert(0 == stat("link4a", &st));
 	assertEqualInt(st.st_mode, (S_IFREG | 0755) & ~UMASK);
 	assertEqualInt(st.st_size, sizeof(data));
 	assertEqualInt(st.st_nlink, 2);
 
-	assert(0 == stat("link3b", &st2));
+	assert(0 == stat("link4b", &st2));
 	assertEqualInt(st2.st_mode, (S_IFREG | 0755) & ~UMASK);
 	assertEqualInt(st2.st_size, sizeof(data));
 	assertEqualInt(st2.st_nlink, 2);