When a sparse file is stored, use a special name in ustar header

according to GNU PAX Format 1.0.

SVN-Revision: 1883

diff --git a/libarchive/archive_write_set_format_pax.c b/libarchive/archive_write_set_format_pax.c
index ffddee0dedf3195de9b5753b0dd534c60c7551f5..892295467430e5f281d657115d2c8c433f276bb9 100644 (file)
--- a/libarchive/archive_write_set_format_pax.c
+++ b/libarchive/archive_write_set_format_pax.c
@@ -76,6 +76,7 @@ static int             archive_write_pax_finish_entry(struct archive_write *);
 static int              archive_write_pax_header(struct archive_write *,
                             struct archive_entry *);
 static char            *base64_encode(const char *src, size_t len);
+static char            *build_gnu_sparse_name(char *dest, const char *src);
 static char            *build_pax_attribute_name(char *dest, const char *src);
 static char            *build_ustar_entry_name(char *dest, const char *src,
                             size_t src_length, const char *insert);
@@ -433,6 +434,8 @@ archive_write_pax_header(struct archive_write *a,
        char ustarbuff[512];
        char ustar_entry_name[256];
        char pax_entry_name[256];
+       char gnu_sparse_name[256];
+       struct archive_string entry_name;
 
        ret = ARCHIVE_OK;
        need_extension = 0;
@@ -641,6 +644,10 @@ archive_write_pax_header(struct archive_write *a,
                        need_extension = 1;
                }
        }
+       /* Save a pathname since it will be renamed if `entry_main` has
+        * sparse blocks. */
+       archive_string_init(&entry_name);
+       archive_strcpy(&entry_name, archive_entry_pathname(entry_main));
 
        /* If file size is too large, add 'size' to pax extended attrs. */
        if (archive_entry_size(entry_main) >= (((int64_t)1) << 33)) {
@@ -861,11 +868,18 @@ archive_write_pax_header(struct archive_write *a,
                        add_pax_attr_int(&(pax->pax_header),
                            "GNU.sparse.minor", 0);
                        add_pax_attr(&(pax->pax_header),
-                           "GNU.sparse.name", path);/*TODO*/
+                           "GNU.sparse.name", entry_name.s);
                        add_pax_attr_int(&(pax->pax_header),
                            "GNU.sparse.realsize",
                            archive_entry_size(entry_main));
 
+                       /* Rename the file name which will be used for
+                        * ustar header to a special name, which GNU
+                        * PAX Format 1.0 requires */
+                       archive_entry_set_pathname(entry_main,
+                           build_gnu_sparse_name(gnu_sparse_name,
+                               entry_name.s));
+
                        /*
                         * - Make a sparse map, which will precede a file data.
                         * - Get the total size of available data of sparse.
@@ -883,6 +897,7 @@ archive_write_pax_header(struct archive_write *a,
                                            ENOMEM,
                                            "Can't allocate memory");
                                        archive_entry_free(entry_main);
+                                       archive_string_free(&entry_name);
                                        return (ARCHIVE_FATAL);
                                }
                        }
@@ -968,7 +983,7 @@ archive_write_pax_header(struct archive_write *a,
                mode_t mode;
 
                pax_attr_entry = archive_entry_new();
-               p = archive_entry_pathname(entry_main);
+               p = entry_name.s;
                archive_entry_set_pathname(pax_attr_entry,
                    build_pax_attribute_name(pax_entry_name, p));
                archive_entry_set_size(pax_attr_entry,
@@ -1071,6 +1086,7 @@ archive_write_pax_header(struct archive_write *a,
        }
        pax->entry_padding = 0x1ff & (-(int64_t)sparse_total);
        archive_entry_free(entry_main);
+       archive_string_free(&entry_name);
 
        return (ret);
 }
@@ -1291,6 +1307,54 @@ build_pax_attribute_name(char *dest, const char *src)
        return (dest);
 }
 
+/*
+ * GNU PAX Format 1.0 requires the special name, which pattern is:
+ * <dir>/GNUSparseFile.<pid>/<original file name>
+ *
+ * This function is used for only Sparse file, a file type of which
+ * is regular file. 
+ */
+static char *
+build_gnu_sparse_name(char *dest, const char *src)
+{
+       char buff[64];
+       const char *p;
+
+       /* Handle the null filename case. */
+       if (src == NULL || *src == '\0') {
+               strcpy(dest, "GNUSparseFile/blank");
+               return (dest);
+       }
+
+       /* Prune final '/' and other unwanted final elements. */
+       p = src + strlen(src);
+       for (;;) {
+               /* Ends in "/", remove the '/' */
+               if (p > src && p[-1] == '/') {
+                       --p;
+                       continue;
+               }
+               /* Ends in "/.", remove the '.' */
+               if (p > src + 1 && p[-1] == '.'
+                   && p[-2] == '/') {
+                       --p;
+                       continue;
+               }
+               break;
+       }
+
+#if HAVE_GETPID && 0  /* Disable this as pax attribute name. */
+       sprintf(buff, "GNUSparseFile.%d", getpid());
+#else
+       /* If the platform can't fetch the pid, don't include it. */
+       strcpy(buff, "GNUSparseFile");
+#endif
+       /* General case: build a ustar-compatible name adding "/GNUSparseFile/". */
+       build_ustar_entry_name(dest, src, p - src, buff);
+
+       return (dest);
+}
+
 /* Write two null blocks for the end of archive */
 static int
 archive_write_pax_finish(struct archive_write *a)