write.c: let compaction work on untruncatable files

[wimlib] / src / write.c

diff --git a/src/write.c b/src/write.c
index 930c61b1d5dad40f0694102c061d4b2514c3f6cb..7f13630cceec991aea303afd27b74f0b1b67f888 100644 (file)
--- a/src/write.c
+++ b/src/write.c
@@ -2430,7 +2430,10 @@ finish_write(WIMStruct *wim, int image, int write_flags,
        ret = WIMLIB_ERR_WRITE;
        if (unlikely(write_flags & WIMLIB_WRITE_FLAG_UNSAFE_COMPACT)) {
                /* Truncate any data the compaction freed up.  */
-               if (ftruncate(wim->out_fd.fd, wim->out_fd.offset)) {
+               if (ftruncate(wim->out_fd.fd, wim->out_fd.offset) &&
+                   errno != EINVAL) /* allow compaction on untruncatable files,
+                                       e.g. block devices  */
+               {
                        ERROR_WITH_ERRNO("Failed to truncate the output WIM file");
                        goto out;
                }
@@ -3110,8 +3113,11 @@ overwrite_wim_inplace(WIMStruct *wim, int write_flags, unsigned num_threads)
                 * this data would be overwritten.  */
                old_xml_begin = wim->hdr.xml_data_reshdr.offset_in_wim;
                old_xml_end = old_xml_begin + wim->hdr.xml_data_reshdr.size_in_wim;
-               old_blob_table_end = wim->hdr.blob_table_reshdr.offset_in_wim +
-                                    wim->hdr.blob_table_reshdr.size_in_wim;
+               if (wim->hdr.blob_table_reshdr.offset_in_wim == 0)
+                       old_blob_table_end = WIM_HEADER_DISK_SIZE;
+               else
+                       old_blob_table_end = wim->hdr.blob_table_reshdr.offset_in_wim +
+                                            wim->hdr.blob_table_reshdr.size_in_wim;
                if (wim_has_integrity_table(wim) &&
                    wim->hdr.integrity_table_reshdr.offset_in_wim < old_xml_end) {
                        WARNING("Didn't expect the integrity table to be "