]> wimlib.net Git - wimlib/blobdiff - src/write.c
Fix typo
[wimlib] / src / write.c
index 29a8f21f0acc5be377f0c8b72bf4736a82c604b0..4d3ade0893b02da6eec64a460a693540c3b09f84 100644 (file)
@@ -43,7 +43,6 @@
 #include "xpress.h"
 
 #ifdef ENABLE_MULTITHREADED_COMPRESSION
-#include <semaphore.h>
 #include <pthread.h>
 #endif
 
 #include <stdlib.h>
 #endif
 
-
-static int do_fflush(FILE *fp)
+static int fflush_and_ftruncate(FILE *fp, off_t size)
 {
-       int ret = fflush(fp);
+       int ret;
+
+       ret = fflush(fp);
        if (ret != 0) {
                ERROR_WITH_ERRNO("Failed to flush data to output WIM file");
                return WIMLIB_ERR_WRITE;
        }
-       return 0;
-}
-
-static int fflush_and_ftruncate(FILE *fp, off_t size)
-{
-       int ret;
-
-       ret = do_fflush(fp);
-       if (ret != 0)
-               return ret;
        ret = ftruncate(fileno(fp), size);
        if (ret != 0) {
                ERROR_WITH_ERRNO("Failed to truncate output WIM file to "
@@ -219,7 +209,7 @@ static int write_wim_resource_chunk(const u8 chunk[], unsigned chunk_size,
 }
 
 /*
- * Finishes a WIM chunk tale and writes it to the output file at the correct
+ * Finishes a WIM chunk table and writes it to the output file at the correct
  * offset.
  *
  * The final size of the full compressed resource is returned in the
@@ -333,6 +323,27 @@ static void end_wim_resource_read(struct lookup_table_entry *lte
 #endif
 }
 
+static int
+write_uncompressed_resource_and_truncate(struct lookup_table_entry *lte,
+                                        FILE *out_fp,
+                                        off_t file_offset,
+                                        struct resource_entry *out_res_entry)
+{
+       int ret;
+       if (fseeko(out_fp, file_offset, SEEK_SET) != 0) {
+               ERROR_WITH_ERRNO("Failed to seek to byte %"PRIu64" of "
+                                "output WIM file", file_offset);
+               return WIMLIB_ERR_WRITE;
+       }
+       ret = write_wim_resource(lte, out_fp, WIMLIB_COMPRESSION_TYPE_NONE,
+                                out_res_entry, 0);
+       if (ret != 0)
+               return ret;
+
+       return fflush_and_ftruncate(out_fp,
+                                   file_offset + wim_resource_size(lte));
+}
+
 /*
  * Writes a WIM resource to a FILE * opened for writing.  The resource may be
  * written uncompressed or compressed depending on the @out_ctype parameter.
@@ -508,18 +519,10 @@ int write_wim_resource(struct lookup_table_entry *lte,
        {
                /* Oops!  We compressed the resource to larger than the original
                 * size.  Write the resource uncompressed instead. */
-               if (fseeko(out_fp, file_offset, SEEK_SET) != 0) {
-                       ERROR_WITH_ERRNO("Failed to seek to byte %"PRIu64" "
-                                        "of output WIM file", file_offset);
-                       ret = WIMLIB_ERR_WRITE;
-                       goto out_fclose;
-               }
-               ret = write_wim_resource(lte, out_fp, WIMLIB_COMPRESSION_TYPE_NONE,
-                                        out_res_entry, flags);
-               if (ret != 0)
-                       goto out_fclose;
-
-               ret = fflush_and_ftruncate(out_fp, file_offset + out_res_entry->size);
+               ret = write_uncompressed_resource_and_truncate(lte,
+                                                              out_fp,
+                                                              file_offset,
+                                                              out_res_entry);
                if (ret != 0)
                        goto out_fclose;
        } else {
@@ -547,13 +550,14 @@ out:
 
 #ifdef ENABLE_MULTITHREADED_COMPRESSION
 struct shared_queue {
-       sem_t filled_slots;
-       sem_t empty_slots;
-       pthread_mutex_t lock;
+       unsigned size;
        unsigned front;
        unsigned back;
+       unsigned filled_slots;
        void **array;
-       unsigned size;
+       pthread_mutex_t lock;
+       pthread_cond_t msg_avail_cond;
+       pthread_cond_t space_avail_cond;
 };
 
 static int shared_queue_init(struct shared_queue *q, unsigned size)
@@ -561,46 +565,52 @@ static int shared_queue_init(struct shared_queue *q, unsigned size)
        q->array = CALLOC(sizeof(q->array[0]), size);
        if (!q->array)
                return WIMLIB_ERR_NOMEM;
-
-       sem_init(&q->filled_slots, 0, 0);
-       sem_init(&q->empty_slots, 0, size);
-       pthread_mutex_init(&q->lock, NULL);
+       q->filled_slots = 0;
        q->front = 0;
        q->back = size - 1;
        q->size = size;
+       pthread_mutex_init(&q->lock, NULL);
+       pthread_cond_init(&q->msg_avail_cond, NULL);
+       pthread_cond_init(&q->space_avail_cond, NULL);
        return 0;
 }
 
 static void shared_queue_destroy(struct shared_queue *q)
 {
-       sem_destroy(&q->filled_slots);
-       sem_destroy(&q->empty_slots);
-       pthread_mutex_destroy(&q->lock);
        FREE(q->array);
+       pthread_mutex_destroy(&q->lock);
+       pthread_cond_destroy(&q->msg_avail_cond);
+       pthread_cond_destroy(&q->space_avail_cond);
 }
 
 static void shared_queue_put(struct shared_queue *q, void *obj)
 {
-       sem_wait(&q->empty_slots);
        pthread_mutex_lock(&q->lock);
+       while (q->filled_slots == q->size)
+               pthread_cond_wait(&q->space_avail_cond, &q->lock);
 
        q->back = (q->back + 1) % q->size;
        q->array[q->back] = obj;
+       q->filled_slots++;
 
-       sem_post(&q->filled_slots);
+       pthread_cond_broadcast(&q->msg_avail_cond);
        pthread_mutex_unlock(&q->lock);
 }
 
 static void *shared_queue_get(struct shared_queue *q)
 {
-       sem_wait(&q->filled_slots);
+       void *obj;
+
        pthread_mutex_lock(&q->lock);
+       while (q->filled_slots == 0)
+               pthread_cond_wait(&q->msg_avail_cond, &q->lock);
 
-       void *obj = q->array[q->front];
+       obj = q->array[q->front];
        q->array[q->front] = NULL;
        q->front = (q->front + 1) % q->size;
+       q->filled_slots--;
 
-       sem_post(&q->empty_slots);
+       pthread_cond_broadcast(&q->space_avail_cond);
        pthread_mutex_unlock(&q->lock);
        return obj;
 }
@@ -784,25 +794,19 @@ static int main_writer_thread_proc(struct list_head *stream_list,
        //
        LIST_HEAD(outstanding_resources);
        struct list_head *next_resource = stream_list->next;
-       struct lookup_table_entry *next_lte = container_of(next_resource,
-                                                          struct lookup_table_entry,
-                                                          staging_list);
-       next_resource = next_resource->next;
+       struct lookup_table_entry *next_lte = NULL;
        u64 next_chunk = 0;
-       u64 next_num_chunks = wim_resource_chunks(next_lte);
-       INIT_LIST_HEAD(&next_lte->msg_list);
-       list_add_tail(&next_lte->staging_list, &outstanding_resources);
+       u64 next_num_chunks = 0;
 
        // As in write_wim_resource(), each resource we read is checksummed.
        SHA_CTX next_sha_ctx;
-       sha1_init(&next_sha_ctx);
        u8 next_hash[SHA1_HASH_SIZE];
 
        // Resources that don't need any chunks compressed are added to this
        // list and written directly by the main thread.
        LIST_HEAD(my_resources);
 
-       struct lookup_table_entry *cur_lte = next_lte;
+       struct lookup_table_entry *cur_lte = NULL;
        struct chunk_table *cur_chunk_tab = NULL;
        struct message *msg;
 
@@ -810,14 +814,6 @@ static int main_writer_thread_proc(struct list_head *stream_list,
        ntfs_inode *ni = NULL;
 #endif
 
-#ifdef WITH_NTFS_3G
-       ret = prepare_resource_for_read(next_lte, &ni);
-#else
-       ret = prepare_resource_for_read(next_lte);
-#endif
-       if (ret != 0)
-               goto out;
-
        DEBUG("Initializing buffers for uncompressed "
              "and compressed data (%zu bytes needed)",
              queue_size * MAX_CHUNKS_PER_MSG * WIM_CHUNK_SIZE * 2);
@@ -827,7 +823,12 @@ static int main_writer_thread_proc(struct list_head *stream_list,
        for (size_t i = 0; i < ARRAY_LEN(msgs); i++) {
                for (size_t j = 0; j < MAX_CHUNKS_PER_MSG; j++) {
                        msgs[i].compressed_chunks[j] = MALLOC(WIM_CHUNK_SIZE);
-                       msgs[i].uncompressed_chunks[j] = MALLOC(WIM_CHUNK_SIZE);
+
+                       // The extra 8 bytes is because longest_match() in lz.c
+                       // may read a little bit off the end of the uncompressed
+                       // data.  It doesn't need to be initialized--- we really
+                       // just need to avoid accessing an unmapped page.
+                       msgs[i].uncompressed_chunks[j] = MALLOC(WIM_CHUNK_SIZE + 8);
                        if (msgs[i].compressed_chunks[j] == NULL ||
                            msgs[i].uncompressed_chunks[j] == NULL)
                        {
@@ -847,7 +848,88 @@ static int main_writer_thread_proc(struct list_head *stream_list,
                // are no more messages available since they were all sent off,
                // or (b) there are no more resources that need to be
                // compressed.
-               while (!list_empty(&available_msgs) && next_lte != NULL) {
+               while (!list_empty(&available_msgs)) {
+                       if (next_chunk == next_num_chunks) {
+                               // If next_chunk == next_num_chunks, there are
+                               // no more chunks to write in the current
+                               // stream.  So, check the SHA1 message digest of
+                               // the stream that was just finished (unless
+                               // next_lte == NULL, which is the case the very
+                               // first time this loop is entered, and also
+                               // near the very end of the compression when
+                               // there are no more streams.)  Then, advance to
+                               // the next stream (if there is one).
+                               if (next_lte != NULL) {
+                               #ifdef WITH_NTFS_3G
+                                       end_wim_resource_read(next_lte, ni);
+                                       ni = NULL;
+                               #else
+                                       end_wim_resource_read(next_lte);
+                               #endif
+                                       DEBUG2("Finalize SHA1 md (next_num_chunks=%zu)",
+                                              next_num_chunks);
+                                       sha1_final(next_hash, &next_sha_ctx);
+                                       if (!hashes_equal(next_lte->hash, next_hash)) {
+                                               ERROR("WIM resource has incorrect hash!");
+                                               if (next_lte->resource_location ==
+                                                   RESOURCE_IN_FILE_ON_DISK)
+                                               {
+                                                       ERROR("We were reading it from `%s'; "
+                                                             "maybe it changed while we were "
+                                                             "reading it.",
+                                                             next_lte->file_on_disk);
+                                               }
+                                               ret = WIMLIB_ERR_INVALID_RESOURCE_HASH;
+                                               goto out;
+                                       }
+                               }
+
+                               // Advance to the next resource.
+                               //
+                               // If the next resource needs no compression, just write
+                               // it with this thread (not now though--- we could be in
+                               // the middle of writing another resource.)  Keep doing
+                               // this until we either get to the end of the resources
+                               // list, or we get to a resource that needs compression.
+                               while (1) {
+                                       if (next_resource == stream_list) {
+                                               next_lte = NULL;
+                                               break;
+                                       }
+                                       next_lte = container_of(next_resource,
+                                                               struct lookup_table_entry,
+                                                               staging_list);
+                                       next_resource = next_resource->next;
+                                       if ((!(write_flags & WIMLIB_WRITE_FLAG_RECOMPRESS)
+                                              && wim_resource_compression_type(next_lte) == out_ctype)
+                                           || wim_resource_size(next_lte) == 0)
+                                       {
+                                               list_add_tail(&next_lte->staging_list,
+                                                             &my_resources);
+                                       } else {
+                                               list_add_tail(&next_lte->staging_list,
+                                                             &outstanding_resources);
+                                               next_chunk = 0;
+                                               next_num_chunks = wim_resource_chunks(next_lte);
+                                               sha1_init(&next_sha_ctx);
+                                               INIT_LIST_HEAD(&next_lte->msg_list);
+                                       #ifdef WITH_NTFS_3G
+                                               ret = prepare_resource_for_read(next_lte, &ni);
+                                       #else
+                                               ret = prepare_resource_for_read(next_lte);
+                                       #endif
+
+                                               if (ret != 0)
+                                                       goto out;
+                                               if (cur_lte == NULL)
+                                                       cur_lte = next_lte;
+                                               break;
+                                       }
+                               }
+                       }
+
+                       if (next_lte == NULL)
+                               break;
 
                        // Get a message from the available messages
                        // list
@@ -902,81 +984,11 @@ static int main_writer_thread_proc(struct list_head *stream_list,
                        list_add_tail(&msg->list, &next_lte->msg_list);
                        shared_queue_put(res_to_compress_queue, msg);
                        DEBUG2("Compression request sent");
-
-                       if (next_chunk != next_num_chunks)
-                               // More chunks to send for this resource
-                               continue;
-
-                       // Done sending compression requests for a resource!
-                       // Check the SHA1 message digest.
-                       DEBUG2("Finalize SHA1 md (next_num_chunks=%zu)", next_num_chunks);
-                       sha1_final(next_hash, &next_sha_ctx);
-                       if (!hashes_equal(next_lte->hash, next_hash)) {
-                               ERROR("WIM resource has incorrect hash!");
-                               if (next_lte->resource_location == RESOURCE_IN_FILE_ON_DISK) {
-                                       ERROR("We were reading it from `%s'; maybe it changed "
-                                             "while we were reading it.",
-                                             next_lte->file_on_disk);
-                               }
-                               ret = WIMLIB_ERR_INVALID_RESOURCE_HASH;
-                               goto out;
-                       }
-
-                       // Advance to the next resource.
-                       //
-                       // If the next resource needs no compression, just write
-                       // it with this thread (not now though--- we could be in
-                       // the middle of writing another resource.)  Keep doing
-                       // this until we either get to the end of the resources
-                       // list, or we get to a resource that needs compression.
-
-                       while (1) {
-                               if (next_resource == stream_list) {
-                                       next_lte = NULL;
-                                       break;
-                               }
-                       #ifdef WITH_NTFS_3G
-                               end_wim_resource_read(next_lte, ni);
-                               ni = NULL;
-                       #else
-                               end_wim_resource_read(next_lte);
-                       #endif
-
-                               next_lte = container_of(next_resource,
-                                                       struct lookup_table_entry,
-                                                       staging_list);
-                               next_resource = next_resource->next;
-                               if ((!(write_flags & WIMLIB_WRITE_FLAG_RECOMPRESS)
-                                     && next_lte->resource_location == RESOURCE_IN_WIM
-                                     && wimlib_get_compression_type(next_lte->wim) == out_ctype)
-                                   || wim_resource_size(next_lte) == 0)
-                               {
-                                       list_add_tail(&next_lte->staging_list,
-                                                     &my_resources);
-                               } else {
-                                       list_add_tail(&next_lte->staging_list,
-                                                     &outstanding_resources);
-                                       next_chunk = 0;
-                                       next_num_chunks = wim_resource_chunks(next_lte);
-                                       sha1_init(&next_sha_ctx);
-                                       INIT_LIST_HEAD(&next_lte->msg_list);
-                               #ifdef WITH_NTFS_3G
-                                       ret = prepare_resource_for_read(next_lte, &ni);
-                               #else
-                                       ret = prepare_resource_for_read(next_lte);
-                               #endif
-                                       if (ret != 0)
-                                               goto out;
-                                       DEBUG2("Updated next_lte");
-                                       break;
-                               }
-                       }
                }
 
                // If there are no outstanding resources, there are no more
                // resources that need to be written.
                if (list_empty(&outstanding_resources)) {
-                       DEBUG("No outstanding resources! Done");
                        ret = 0;
                        goto out;
                }
@@ -984,23 +996,16 @@ static int main_writer_thread_proc(struct list_head *stream_list,
                // Get the next message from the queue and process it.
                // The message will contain 1 or more data chunks that have been
                // compressed.
-               DEBUG2("Waiting for message");
                msg = shared_queue_get(compressed_res_queue);
                msg->complete = true;
 
-               DEBUG2("Received msg (begin_chunk=%"PRIu64")", msg->begin_chunk);
-
-               list_for_each_entry(msg, &cur_lte->msg_list, list) {
-                       DEBUG2("complete=%d", msg->complete);
-               }
-
                // Is this the next chunk in the current resource?  If it's not
                // (i.e., an earlier chunk in a same or different resource
                // hasn't been compressed yet), do nothing, and keep this
                // message around until all earlier chunks are received.
                //
                // Otherwise, write all the chunks we can.
-               while (!list_empty(&cur_lte->msg_list)
+               while (cur_lte != NULL && !list_empty(&cur_lte->msg_list)
                        && (msg = container_of(cur_lte->msg_list.next,
                                               struct message,
                                               list))->complete)
@@ -1048,6 +1053,32 @@ static int main_writer_thread_proc(struct list_head *stream_list,
                                if (ret != 0)
                                        goto out;
 
+                               if (res_csize >= wim_resource_size(cur_lte)) {
+                                       /* Oops!  We compressed the resource to
+                                        * larger than the original size.  Write
+                                        * the resource uncompressed instead. */
+                                       ret = write_uncompressed_resource_and_truncate(
+                                                        cur_lte,
+                                                        out_fp,
+                                                        cur_chunk_tab->file_offset,
+                                                        &cur_lte->output_resource_entry);
+                                       if (ret != 0)
+                                               goto out;
+                               } else {
+                                       cur_lte->output_resource_entry.size =
+                                               res_csize;
+
+                                       cur_lte->output_resource_entry.original_size =
+                                               cur_lte->resource_entry.original_size;
+
+                                       cur_lte->output_resource_entry.offset =
+                                               cur_chunk_tab->file_offset;
+
+                                       cur_lte->output_resource_entry.flags =
+                                               cur_lte->resource_entry.flags |
+                                                       WIM_RESHDR_FLAG_COMPRESSED;
+                               }
+
                                progress->write_streams.completed_bytes +=
                                                wim_resource_size(cur_lte);
                                progress->write_streams.completed_streams++;
@@ -1057,19 +1088,6 @@ static int main_writer_thread_proc(struct list_head *stream_list,
                                                      progress);
                                }
 
-                               cur_lte->output_resource_entry.size =
-                                       res_csize;
-
-                               cur_lte->output_resource_entry.original_size =
-                                       cur_lte->resource_entry.original_size;
-
-                               cur_lte->output_resource_entry.offset =
-                                       cur_chunk_tab->file_offset;
-
-                               cur_lte->output_resource_entry.flags =
-                                       cur_lte->resource_entry.flags |
-                                               WIM_RESHDR_FLAG_COMPRESSED;
-
                                FREE(cur_chunk_tab);
                                cur_chunk_tab = NULL;
 
@@ -1077,9 +1095,15 @@ static int main_writer_thread_proc(struct list_head *stream_list,
                                list_del(&cur_lte->staging_list);
 
                                if (next == &outstanding_resources) {
-                                       DEBUG("No more outstanding resources");
-                                       ret = 0;
-                                       goto out;
+                                       if (next_lte == NULL) {
+                                               DEBUG("No more outstanding resources");
+                                               ret = 0;
+                                               goto out;
+                                       } else {
+                                               DEBUG("No more outstanding resources---"
+                                                     "but still more to compress!");
+                                               cur_lte = NULL;
+                                       }
                                } else {
                                        cur_lte = container_of(cur_lte->staging_list.next,
                                                               struct lookup_table_entry,
@@ -1106,11 +1130,14 @@ static int main_writer_thread_proc(struct list_head *stream_list,
        }
 
 out:
+       if (next_lte) {
 #ifdef WITH_NTFS_3G
-       end_wim_resource_read(cur_lte, ni);
+               end_wim_resource_read(next_lte, ni);
 #else
-       end_wim_resource_read(cur_lte);
+               end_wim_resource_read(next_lte);
 #endif
+       }
+
        if (ret == 0) {
                ret = do_write_stream_list(&my_resources, out_fp,
                                           out_ctype, progress_func,
@@ -1253,6 +1280,7 @@ static int write_stream_list(struct list_head *stream_list, FILE *out_fp,
        struct lookup_table_entry *lte;
        size_t num_streams = 0;
        u64 total_bytes = 0;
+       u64 total_compression_bytes = 0;
        bool compression_needed = false;
        union wimlib_progress_info progress;
        int ret;
@@ -1260,14 +1288,12 @@ static int write_stream_list(struct list_head *stream_list, FILE *out_fp,
        list_for_each_entry(lte, stream_list, staging_list) {
                num_streams++;
                total_bytes += wim_resource_size(lte);
-               if (!compression_needed
-                   &&
-                   (out_ctype != WIMLIB_COMPRESSION_TYPE_NONE
-                      && (lte->resource_location != RESOURCE_IN_WIM
-                          || wimlib_get_compression_type(lte->wim) != out_ctype
-                          || (write_flags & WIMLIB_WRITE_FLAG_REBUILD)))
-                   && wim_resource_size(lte) != 0)
-                       compression_needed = true;
+               if (out_ctype != WIMLIB_COMPRESSION_TYPE_NONE
+                      && (wim_resource_compression_type(lte) != out_ctype ||
+                          (write_flags & WIMLIB_WRITE_FLAG_RECOMPRESS)))
+               {
+                       total_compression_bytes += wim_resource_size(lte);
+               }
        }
        progress.write_streams.total_bytes       = total_bytes;
        progress.write_streams.total_streams     = num_streams;
@@ -1282,7 +1308,7 @@ static int write_stream_list(struct list_head *stream_list, FILE *out_fp,
        }
 
 #ifdef ENABLE_MULTITHREADED_COMPRESSION
-       if (compression_needed && total_bytes >= 1000000 && num_threads != 1) {
+       if (total_compression_bytes >= 1000000 && num_threads != 1) {
                ret = write_stream_list_parallel(stream_list,
                                                 out_fp,
                                                 out_ctype,
@@ -1523,7 +1549,6 @@ static int open_wim_writable(WIMStruct *w, const char *path,
                             bool trunc, bool readable)
 {
        const char *mode;
-       int ret = 0;
        if (trunc)
                if (readable)
                        mode = "w+b";
@@ -1532,26 +1557,18 @@ static int open_wim_writable(WIMStruct *w, const char *path,
        else
                mode = "r+b";
 
-       DEBUG("Opening `%s' read-write", path);
        wimlib_assert(w->out_fp == NULL);
-       wimlib_assert(path != NULL);
        w->out_fp = fopen(path, mode);
-       if (!w->out_fp) {
+       if (w->out_fp) {
+               return 0;
+       } else {
                ERROR_WITH_ERRNO("Failed to open `%s' for writing", path);
                return WIMLIB_ERR_OPEN;
        }
-       if (trunc) {
-               ret = lock_wim(w->out_fp, path);
-               if (ret != 0) {
-                       fclose(w->out_fp);
-                       w->out_fp = NULL;
-               }
-       }
-       return ret;
 }
 
 
-static void close_wim_writable(WIMStruct *w)
+void close_wim_writable(WIMStruct *w)
 {
        if (w->out_fp) {
                if (fclose(w->out_fp) != 0) {
@@ -1566,12 +1583,8 @@ static void close_wim_writable(WIMStruct *w)
 int begin_write(WIMStruct *w, const char *path, int write_flags)
 {
        int ret;
-       bool need_readable = false;
-       bool trunc = true;
-       if (write_flags & WIMLIB_WRITE_FLAG_CHECK_INTEGRITY)
-               need_readable = true;
-
-       ret = open_wim_writable(w, path, trunc, need_readable);
+       ret = open_wim_writable(w, path, true,
+                               (write_flags & WIMLIB_WRITE_FLAG_CHECK_INTEGRITY) != 0);
        if (ret != 0)
                return ret;
        /* Write dummy header. It will be overwritten later. */
@@ -1745,10 +1758,6 @@ static int overwrite_wim_inplace(WIMStruct *w, int write_flags,
        INIT_LIST_HEAD(&stream_list);
        for (int i = modified_image_idx; i < w->hdr.image_count; i++) {
                DEBUG("Identifiying streams in image %d", i + 1);
-               wimlib_assert(w->image_metadata[i].modified);
-               wimlib_assert(!w->image_metadata[i].has_been_mounted_rw);
-               wimlib_assert(w->image_metadata[i].root_dentry != NULL);
-               wimlib_assert(w->image_metadata[i].metadata_lte != NULL);
                w->private = &stream_list;
                for_dentry_in_tree(w->image_metadata[i].root_dentry,
                                   dentry_find_streams_to_write, w);
@@ -1767,7 +1776,6 @@ static int overwrite_wim_inplace(WIMStruct *w, int write_flags,
        if (modified_image_idx == w->hdr.image_count && !w->deletion_occurred) {
                /* If no images have been modified and no images have been
                 * deleted, a new lookup table does not need to be written. */
-               wimlib_assert(list_empty(&stream_list));
                old_wim_end = w->hdr.lookup_table_res_entry.offset +
                              w->hdr.lookup_table_res_entry.size;
                write_flags |= WIMLIB_WRITE_FLAG_NO_LOOKUP_TABLE |
@@ -1783,9 +1791,17 @@ static int overwrite_wim_inplace(WIMStruct *w, int write_flags,
        if (ret != 0)
                return ret;
 
+       ret = lock_wim(w->out_fp, w->filename);
+       if (ret != 0) {
+               fclose(w->out_fp);
+               w->out_fp = NULL;
+               return ret;
+       }
+
        if (fseeko(w->out_fp, old_wim_end, SEEK_SET) != 0) {
                ERROR_WITH_ERRNO("Can't seek to end of WIM");
-               return WIMLIB_ERR_WRITE;
+               ret = WIMLIB_ERR_WRITE;
+               goto out_ftruncate;
        }
 
        if (!list_empty(&stream_list)) {
@@ -1845,12 +1861,6 @@ static int overwrite_wim_via_tmpfile(WIMStruct *w, int write_flags,
                goto err;
        }
 
-       /* Close the original WIM file that was opened for reading. */
-       if (w->fp != NULL) {
-               fclose(w->fp);
-               w->fp = NULL;
-       }
-
        DEBUG("Renaming `%s' to `%s'", tmpfile, w->filename);
 
        /* Rename the new file to the old file .*/
@@ -1868,12 +1878,20 @@ static int overwrite_wim_via_tmpfile(WIMStruct *w, int write_flags,
                progress_func(WIMLIB_PROGRESS_MSG_RENAME, &progress);
        }
 
+       /* Close the original WIM file that was opened for reading. */
+       if (w->fp != NULL) {
+               fclose(w->fp);
+               w->fp = NULL;
+       }
+
        /* Re-open the WIM read-only. */
        w->fp = fopen(w->filename, "rb");
        if (w->fp == NULL) {
                ret = WIMLIB_ERR_REOPEN;
                WARNING("Failed to re-open `%s' read-only: %s",
                        w->filename, strerror(errno));
+               FREE(w->filename);
+               w->filename = NULL;
        }
        return ret;
 err: