Partial fixes and comments
authorEric Biggers <ebiggers3@gmail.com>
Wed, 22 Aug 2012 05:55:58 +0000 (00:55 -0500)
committerEric Biggers <ebiggers3@gmail.com>
Wed, 22 Aug 2012 05:55:58 +0000 (00:55 -0500)
src/lookup_table.c
src/lookup_table.h
src/resource.c

index e6b8fb2cbafcc86ee033b9d4dd5b579e0b9886d3..0c6a55fcccb9463c8092fda7269ef09b048745a8 100644 (file)
@@ -76,7 +76,9 @@ void free_lookup_table_entry(struct lookup_table_entry *lte)
        if (lte) {
                if (lte->staging_list.next)
                        list_del(&lte->staging_list);
        if (lte) {
                if (lte->staging_list.next)
                        list_del(&lte->staging_list);
-               FREE(lte->file_on_disk);
+               if (lte->resource_location != RESOURCE_IN_WIM &&
+                   lte->resource_location != RESOURCE_NONEXISTENT)
+                       FREE(lte->file_on_disk);
                FREE(lte);
        }
 }
                FREE(lte);
        }
 }
@@ -273,7 +275,7 @@ int zero_out_refcnts(struct lookup_table_entry *entry, void *ignore)
        return 0;
 }
 
        return 0;
 }
 
-void print_lookup_table_entry(struct lookup_table_entry *lte)
+void print_lookup_table_entry(const struct lookup_table_entry *lte)
 {
        if (!lte) {
                putchar('\n');
 {
        if (!lte) {
                putchar('\n');
index c68d89adea6a6370c0986ce15e9d2b0565dba2f4..43dbd4bb9f250b1da8c3cf8c105c774d1619fc86 100644 (file)
@@ -123,11 +123,15 @@ static inline u64 wim_resource_size(const struct lookup_table_entry *lte)
        return lte->resource_entry.original_size;
 }
 
        return lte->resource_entry.original_size;
 }
 
+/*
+ * XXX Probably should store the compression type directly in the lookup table
+ * entry
+ */
 static inline int
 wim_resource_compression_type(const struct lookup_table_entry *lte)
 {
        if (!(lte->resource_entry.flags & WIM_RESHDR_FLAG_COMPRESSED)
 static inline int
 wim_resource_compression_type(const struct lookup_table_entry *lte)
 {
        if (!(lte->resource_entry.flags & WIM_RESHDR_FLAG_COMPRESSED)
-           || !lte->wim)
+           || lte->resource_location != RESOURCE_IN_WIM)
                return WIM_COMPRESSION_TYPE_NONE;
        return wimlib_get_compression_type(lte->wim);
 }
                return WIM_COMPRESSION_TYPE_NONE;
        return wimlib_get_compression_type(lte->wim);
 }
@@ -171,7 +175,7 @@ extern int lookup_resource(WIMStruct *w, const char *path,
 
 extern int zero_out_refcnts(struct lookup_table_entry *entry, void *ignore);
 
 
 extern int zero_out_refcnts(struct lookup_table_entry *entry, void *ignore);
 
-extern void print_lookup_table_entry(struct lookup_table_entry *entry);
+extern void print_lookup_table_entry(const struct lookup_table_entry *entry);
 
 extern int read_lookup_table(WIMStruct *w);
 
 
 extern int read_lookup_table(WIMStruct *w);
 
index 78adfafe6415ea85bfc46524f44cf5cbaa3868ba..8f85cba40b90f42c45c3bc288662fcbb4df2b124 100644 (file)
@@ -346,6 +346,8 @@ err:
 int read_uncompressed_resource(FILE *fp, u64 offset, u64 len,
                               u8 contents_ret[])
 {
 int read_uncompressed_resource(FILE *fp, u64 offset, u64 len,
                               u8 contents_ret[])
 {
+       DEBUG("fp = %p, offset = %lu, len = %lu, contents_ret = %p",
+                       fp, offset, len, contents_ret);
        if (fseeko(fp, offset, SEEK_SET) != 0) {
                ERROR("Failed to seek to byte %"PRIu64" of input file "
                      "to read uncompressed resource (len = %"PRIu64")",
        if (fseeko(fp, offset, SEEK_SET) != 0) {
                ERROR("Failed to seek to byte %"PRIu64" of input file "
                      "to read uncompressed resource (len = %"PRIu64")",
@@ -397,18 +399,38 @@ u8 *put_resource_entry(u8 *p, const struct resource_entry *entry)
        return p;
 }
 
        return p;
 }
 
+/*
+ * Reads some data from a WIM resource.
+ *
+ * If %raw is true, compressed data is read literally rather than being
+ * decompressed first.
+ *
+ * Returns zero on success, nonzero on failure.
+ */
 static int __read_wim_resource(const struct lookup_table_entry *lte,
                               u8 buf[], size_t size, u64 offset, bool raw)
 {
 static int __read_wim_resource(const struct lookup_table_entry *lte,
                               u8 buf[], size_t size, u64 offset, bool raw)
 {
+       /* We shouldn't be allowing read over-runs in any part of the library.
+        * */
        wimlib_assert(offset + size <= wim_resource_size(lte));
        wimlib_assert(offset + size <= wim_resource_size(lte));
+
+       DEBUG("lte = %p, buf = %p, size = %zu, offset = %lu, raw = %d",
+                       lte, buf, size, offset, raw);
+       print_lookup_table_entry(lte);
+
        int ctype;
        int ret;
        FILE *fp;
        switch (lte->resource_location) {
        case RESOURCE_IN_WIM:
        int ctype;
        int ret;
        FILE *fp;
        switch (lte->resource_location) {
        case RESOURCE_IN_WIM:
+               /* The resource is in a WIM file, and its WIMStruct is given by
+                * the lte->wim member.  The resource may be either compressed
+                * or uncompressed. */
                wimlib_assert(lte->wim);
                wimlib_assert(lte->wim->fp);
                ctype = wim_resource_compression_type(lte);
                wimlib_assert(lte->wim);
                wimlib_assert(lte->wim->fp);
                ctype = wim_resource_compression_type(lte);
+
+               /* XXX This check should be moved elsewhere */
                if (ctype == WIM_COMPRESSION_TYPE_NONE &&
                     lte->resource_entry.original_size !=
                      lte->resource_entry.size) {
                if (ctype == WIM_COMPRESSION_TYPE_NONE &&
                     lte->resource_entry.original_size !=
                      lte->resource_entry.size) {
@@ -420,9 +442,11 @@ static int __read_wim_resource(const struct lookup_table_entry *lte,
                              lte->resource_entry.original_size);
                        return WIMLIB_ERR_INVALID_RESOURCE_SIZE;
                }
                              lte->resource_entry.original_size);
                        return WIMLIB_ERR_INVALID_RESOURCE_SIZE;
                }
+
                if (raw || ctype == WIM_COMPRESSION_TYPE_NONE)
                        return read_uncompressed_resource(lte->wim->fp,
                if (raw || ctype == WIM_COMPRESSION_TYPE_NONE)
                        return read_uncompressed_resource(lte->wim->fp,
-                                                         offset, size, buf);
+                                                         lte->resource_entry.offset,
+                                                         size, buf);
                else
                        return read_compressed_resource(lte->wim->fp,
                                                        lte->resource_entry.size,
                else
                        return read_compressed_resource(lte->wim->fp,
                                                        lte->resource_entry.size,
@@ -431,11 +455,18 @@ static int __read_wim_resource(const struct lookup_table_entry *lte,
                                                        ctype, size, offset, buf);
                break;
        case RESOURCE_IN_STAGING_FILE:
                                                        ctype, size, offset, buf);
                break;
        case RESOURCE_IN_STAGING_FILE:
+               /* The WIM FUSE implementation needs to handle multiple open
+                * file descriptors per lookup table entry so it does not
+                * currently work with this function. */
                wimlib_assert(lte->staging_file_name);
                wimlib_assert(0);
                break;
        case RESOURCE_IN_FILE_ON_DISK:
                wimlib_assert(lte->staging_file_name);
                wimlib_assert(0);
                break;
        case RESOURCE_IN_FILE_ON_DISK:
+               /* The resource is in some file on the external filesystem and
+                * needs to be read uncompressed */
                wimlib_assert(lte->file_on_disk);
                wimlib_assert(lte->file_on_disk);
+               /* Use existing file pointer if available; otherwise open one
+                * temporarily */
                if (lte->file_on_disk_fp) {
                        fp = lte->file_on_disk_fp;
                } else {
                if (lte->file_on_disk_fp) {
                        fp = lte->file_on_disk_fp;
                } else {
@@ -445,13 +476,14 @@ static int __read_wim_resource(const struct lookup_table_entry *lte,
                                                 "`%s'", lte->file_on_disk);
                        }
                }
                                                 "`%s'", lte->file_on_disk);
                        }
                }
-               ret = read_uncompressed_resource(lte->file_on_disk_fp,
-                                                offset, size, buf);
+               ret = read_uncompressed_resource(fp, offset, size, buf);
                if (fp != lte->file_on_disk_fp)
                        fclose(fp);
                return ret;
                break;
        case RESOURCE_IN_ATTACHED_BUFFER:
                if (fp != lte->file_on_disk_fp)
                        fclose(fp);
                return ret;
                break;
        case RESOURCE_IN_ATTACHED_BUFFER:
+               /* The resource is directly attached uncompressed in an
+                * in-memory buffer. */
                wimlib_assert(lte->attached_buffer);
                memcpy(buf, lte->attached_buffer + offset, size);
                return 0;
                wimlib_assert(lte->attached_buffer);
                memcpy(buf, lte->attached_buffer + offset, size);
                return 0;
@@ -461,12 +493,32 @@ static int __read_wim_resource(const struct lookup_table_entry *lte,
        }
 }
 
        }
 }
 
+/* 
+ * Reads some data from the resource corresponding to a WIM lookup table entry.
+ *
+ * @lte:       The WIM lookup table entry for the resource.
+ * @buf:       Buffer into which to write the data.
+ * @size:      Number of bytes to read.
+ * @offset:    Offset at which to start reading the resource.
+ *
+ * Returns 0 on success; nonzero on failure.
+ */
 int read_wim_resource(const struct lookup_table_entry *lte, u8 buf[],
                      size_t size, u64 offset)
 {
        return __read_wim_resource(lte, buf, size, offset, false);
 }
 
 int read_wim_resource(const struct lookup_table_entry *lte, u8 buf[],
                      size_t size, u64 offset)
 {
        return __read_wim_resource(lte, buf, size, offset, false);
 }
 
+/* 
+ * Reads all the data from the resource corresponding to a WIM lookup table
+ * entry.
+ *
+ * @lte:       The WIM lookup table entry for the resource.
+ * @buf:       Buffer into which to write the data.  It must be at least
+ *             wim_resource_size(lte) bytes long.
+ *
+ * Returns 0 on success; nonzero on failure.
+ */
 int read_full_wim_resource(const struct lookup_table_entry *lte, u8 buf[])
 {
        return __read_wim_resource(lte, buf, lte->resource_entry.original_size,
 int read_full_wim_resource(const struct lookup_table_entry *lte, u8 buf[])
 {
        return __read_wim_resource(lte, buf, lte->resource_entry.original_size,
@@ -487,6 +539,7 @@ struct chunk_table {
 static int
 begin_wim_resource_chunk_tab(const struct lookup_table_entry *lte,
                             FILE *out_fp,
 static int
 begin_wim_resource_chunk_tab(const struct lookup_table_entry *lte,
                             FILE *out_fp,
+                            off_t file_offset,
                             struct chunk_table **chunk_tab_ret)
 {
        u64 size = wim_resource_size(lte);
                             struct chunk_table **chunk_tab_ret)
 {
        u64 size = wim_resource_size(lte);
@@ -501,12 +554,7 @@ begin_wim_resource_chunk_tab(const struct lookup_table_entry *lte,
                ret = WIMLIB_ERR_NOMEM;
                goto out;
        }
                ret = WIMLIB_ERR_NOMEM;
                goto out;
        }
-       chunk_tab->file_offset = ftello(out_fp);
-       if (chunk_tab->file_offset == -1) {
-               ERROR_WITH_ERRNO("Failed to get file offset in output WIM");
-               ret = WIMLIB_ERR_WRITE;
-               goto out;
-       }
+       chunk_tab->file_offset = file_offset;
        chunk_tab->num_chunks = num_chunks;
        chunk_tab->cur_offset_p = chunk_tab->offsets;
        chunk_tab->original_resource_size = lte->resource_entry.original_size;
        chunk_tab->num_chunks = num_chunks;
        chunk_tab->cur_offset_p = chunk_tab->offsets;
        chunk_tab->original_resource_size = lte->resource_entry.original_size;
@@ -584,8 +632,8 @@ static int write_wim_resource_chunk(const u8 chunk[], unsigned chunk_size,
 }
 
 static int
 }
 
 static int
-finish_wim_resource_chunk_tab(const struct chunk_table *chunk_tab,
-                             FILE *out_fp)
+finish_wim_resource_chunk_tab(struct chunk_table *chunk_tab,
+                             FILE *out_fp, u64 *compressed_size_p)
 {
        if (fseeko(out_fp, chunk_tab->file_offset, SEEK_SET) != 0) {
                ERROR_WITH_ERRNO("Failed to seet to byte "PRIu64" of output "
 {
        if (fseeko(out_fp, chunk_tab->file_offset, SEEK_SET) != 0) {
                ERROR_WITH_ERRNO("Failed to seet to byte "PRIu64" of output "
@@ -612,48 +660,102 @@ finish_wim_resource_chunk_tab(const struct chunk_table *chunk_tab,
                                 "WIM file", chunk_tab->file_offset);
                return WIMLIB_ERR_WRITE;
        }
                                 "WIM file", chunk_tab->file_offset);
                return WIMLIB_ERR_WRITE;
        }
+       *compressed_size_p = chunk_tab->cur_offset;
        return 0;
 }
 
        return 0;
 }
 
-static int write_wim_resource(const struct lookup_table_entry *lte,
-                             FILE *out_fp, int out_ctype)
+/*
+ * Writes a WIM resource to a FILE * opened for writing.  The resource may be
+ * written uncompressed or compressed depending on the @out_ctype parameter.
+ *
+ * @lte:       The lookup table entry for the WIM resource.
+ * @out_fp:    The FILE * to write the resource to.
+ * @out_ctype:  The compression type of the resource to write.  Note: if this is
+ *                     the same as the compression type of the WIM resource we
+ *                     need to read, we simply copy the data (i.e. we do not
+ *                     uncompress it, then compress it again).
+ * @out_res_entry:  If non-NULL, a resource entry that is filled in with the 
+ *                 offset, original size, compressed size, and compression flag
+ *                 of the output resource.
+ *
+ * Returns 0 on success; nonzero on failure.
+ */
+static int __write_wim_resource(const struct lookup_table_entry *lte,
+                               FILE *out_fp, int out_ctype,
+                               struct resource_entry *out_res_entry)
 {
 {
-       u64 bytes_remaining = wim_resource_size(lte);
+       u64 size = wim_resource_size(lte);
+       u64 bytes_remaining = size;
        char buf[min(WIM_CHUNK_SIZE, bytes_remaining)];
        u64 offset = 0;
        char buf[min(WIM_CHUNK_SIZE, bytes_remaining)];
        u64 offset = 0;
+       u64 compressed_size = bytes_remaining;
        int ret = 0;
        int ret = 0;
-       bool raw = wim_resource_compression_type(lte) == out_ctype;
        struct chunk_table *chunk_tab = NULL;
        struct chunk_table *chunk_tab = NULL;
+       bool raw;
+       off_t file_offset;
 
 
+       if (out_res_entry) {
+               file_offset = ftello(out_fp);
+               if (file_offset == -1) {
+                       ERROR_WITH_ERRNO("Failed to get offset in output "
+                                        "stream");
+                       return WIMLIB_ERR_WRITE;
+               }
+       }
+       
+       raw = (wim_resource_compression_type(lte) == out_ctype);
        if (raw)
                out_ctype = WIM_COMPRESSION_TYPE_NONE;
 
        if (out_ctype != WIM_COMPRESSION_TYPE_NONE) {
        if (raw)
                out_ctype = WIM_COMPRESSION_TYPE_NONE;
 
        if (out_ctype != WIM_COMPRESSION_TYPE_NONE) {
-               ret = begin_wim_resource_chunk_tab(lte, out_fp,
+               ret = begin_wim_resource_chunk_tab(lte, out_fp, file_offset,
                                                   &chunk_tab);
                if (ret != 0)
                                                   &chunk_tab);
                if (ret != 0)
-                       return 0;
+                       goto out;
        }
 
        while (bytes_remaining) {
                u64 to_read = min(bytes_remaining, WIM_CHUNK_SIZE);
                ret = __read_wim_resource(lte, buf, to_read, offset, raw);
                if (ret != 0)
        }
 
        while (bytes_remaining) {
                u64 to_read = min(bytes_remaining, WIM_CHUNK_SIZE);
                ret = __read_wim_resource(lte, buf, to_read, offset, raw);
                if (ret != 0)
-                       break;
+                       goto out;
                ret = write_wim_resource_chunk(buf, to_read, out_fp,
                                               out_ctype, chunk_tab);
                if (ret != 0)
                ret = write_wim_resource_chunk(buf, to_read, out_fp,
                                               out_ctype, chunk_tab);
                if (ret != 0)
-                       break;
+                       goto out;
                bytes_remaining -= to_read;
                offset += to_read;
        }
                bytes_remaining -= to_read;
                offset += to_read;
        }
-       if (out_ctype != WIM_COMPRESSION_TYPE_NONE)
-               ret = finish_wim_resource_chunk_tab(chunk_tab, out_fp);
+       if (out_ctype != WIM_COMPRESSION_TYPE_NONE) {
+               ret = finish_wim_resource_chunk_tab(chunk_tab, out_fp,
+                                                   &compressed_size);
+               if (ret != 0)
+                       goto out;
+       }
+       if (out_res_entry) {
+               out_res_entry->size          = compressed_size;
+               out_res_entry->original_size = size;
+               out_res_entry->offset       = file_offset;
+               if (out_ctype == WIM_COMPRESSION_TYPE_NONE)
+                       out_res_entry->flags = 0;
+               else
+                       out_res_entry->flags = WIM_RESHDR_FLAG_COMPRESSED;
+       }
+out:
+       FREE(chunk_tab);
        return ret;
 }
 
        return ret;
 }
 
+static int write_wim_resource(struct lookup_table_entry *lte,
+                             FILE *out_fp, int out_ctype)
+{
+       return __write_wim_resource(lte, out_fp, out_ctype,
+                                   &lte->output_resource_entry);
+}
+
 static int write_wim_resource_from_buffer(const u8 *buf, u64 buf_size,
 static int write_wim_resource_from_buffer(const u8 *buf, u64 buf_size,
-                                         FILE *out_fp, int out_ctype)
+                                         FILE *out_fp, int out_ctype,
+                                         struct resource_entry *out_res_entry)
 {
        struct lookup_table_entry lte;
        lte.resource_entry.flags = 0;
 {
        struct lookup_table_entry lte;
        lte.resource_entry.flags = 0;
@@ -662,7 +764,7 @@ static int write_wim_resource_from_buffer(const u8 *buf, u64 buf_size,
        lte.resource_entry.offset = 0;
        lte.resource_location = RESOURCE_IN_ATTACHED_BUFFER;
        lte.attached_buffer = (u8*)buf;
        lte.resource_entry.offset = 0;
        lte.resource_location = RESOURCE_IN_ATTACHED_BUFFER;
        lte.attached_buffer = (u8*)buf;
-       return write_wim_resource(&lte, out_fp, out_ctype);
+       return __write_wim_resource(&lte, out_fp, out_ctype, out_res_entry);
 }
 
 /* 
 }
 
 /* 
@@ -713,28 +815,14 @@ int copy_resource(struct lookup_table_entry *lte, void *wim)
 {
        WIMStruct *w = wim;
        int ret;
 {
        WIMStruct *w = wim;
        int ret;
-       off_t new_offset;
 
        if ((lte->resource_entry.flags & WIM_RESHDR_FLAG_METADATA) &&
            !w->write_metadata)
                return 0;
 
 
        if ((lte->resource_entry.flags & WIM_RESHDR_FLAG_METADATA) &&
            !w->write_metadata)
                return 0;
 
-       new_offset = ftello(w->out_fp);
-       if (new_offset == -1) {
-               ERROR_WITH_ERRNO("Could not get offset in output WIM");
-               return WIMLIB_ERR_WRITE;
-       }
-
-
-       ret = write_wim_resource(lte, w->out_fp,
-                                wimlib_get_compression_type((WIMStruct*)w));
+       ret = write_wim_resource(lte, w->out_fp, wimlib_get_compression_type(w));
        if (ret != 0)
                return ret;
        if (ret != 0)
                return ret;
-
-       memcpy(&lte->output_resource_entry, &lte->resource_entry, 
-              sizeof(struct resource_entry));
-
-       lte->output_resource_entry.offset = new_offset;
        lte->out_refcnt = lte->refcnt;
        lte->part_number = w->hdr.part_number;
        return 0;
        lte->out_refcnt = lte->refcnt;
        lte->part_number = w->hdr.part_number;
        return 0;
@@ -953,29 +1041,19 @@ int write_metadata_resource(WIMStruct *w)
        sha1_buffer(buf, metadata_original_size, hash);
 
 
        sha1_buffer(buf, metadata_original_size, hash);
 
 
+       lte = wim_metadata_lookup_table_entry(w);
+
        ret = write_wim_resource_from_buffer(buf, metadata_original_size,
        ret = write_wim_resource_from_buffer(buf, metadata_original_size,
-                                            out, metadata_ctype);
+                                            out, metadata_ctype,
+                                            &lte->output_resource_entry);
        FREE(buf);
        if (ret != 0)
                return ret;
 
        FREE(buf);
        if (ret != 0)
                return ret;
 
-       DEBUG("Updating metadata lookup table entry (size %zu)",
-             metadata_original_size);
-
-       /* Update the lookup table entry, including the hash and output resource
-        * entry fields, for this image's metadata resource.  */
-       lte = wim_metadata_lookup_table_entry(w);
        lte->out_refcnt++;
        lte->out_refcnt++;
-       if (!hashes_equal(hash, lte->hash)) {
-               lookup_table_unlink(w->lookup_table, lte);
-               copy_hash(lte->hash, hash);
-               lookup_table_insert(w->lookup_table, lte);
-       }
-       lte->output_resource_entry.original_size = metadata_original_size;
-       lte->output_resource_entry.offset        = metadata_offset;
-       lte->output_resource_entry.size          = metadata_compressed_size;
-       lte->output_resource_entry.flags         = WIM_RESHDR_FLAG_METADATA;
-       if (metadata_ctype != WIM_COMPRESSION_TYPE_NONE)
-               lte->output_resource_entry.flags |= WIM_RESHDR_FLAG_COMPRESSED;
+       lte->output_resource_entry.flags |= WIM_RESHDR_FLAG_METADATA;
+       lookup_table_unlink(w->lookup_table, lte);
+       copy_hash(lte->hash, hash);
+       lookup_table_insert(w->lookup_table, lte);
        return 0;
 }
        return 0;
 }