resource.c: Don't manually align buffer for uncompressed data

[wimlib] / src / resource.c

diff --git a/src/resource.c b/src/resource.c
index fb5761d9e68ba60cf7bbf262efb4ce0e303ad5a1..13c1581fc866ff48e51fef709ef75887c0109c3c 100644 (file)
--- a/src/resource.c
+++ b/src/resource.c
@@ -26,6 +26,7 @@
 #endif
 
 #include "wimlib/assert.h"
+#include "wimlib/bitops.h"
 #include "wimlib/endianness.h"
 #include "wimlib/error.h"
 #include "wimlib/file_io.h"
@@ -136,7 +137,6 @@ read_compressed_wim_resource(const struct wim_resource_spec * const rspec,
        int errno_save;
 
        u64 *chunk_offsets = NULL;
-       u8 *_ubuf = NULL;
        u8 *ubuf = NULL;
        void *cbuf = NULL;
        bool chunk_offsets_malloced = false;
@@ -214,7 +214,7 @@ read_compressed_wim_resource(const struct wim_resource_spec * const rspec,
                }
        }
 
-       const u32 chunk_order = bsr32(chunk_size);
+       const u32 chunk_order = fls32(chunk_size);
 
        /* Calculate the total number of chunks the resource is divided into.  */
        const u64 num_chunks = (rspec->uncompressed_size + chunk_size - 1) >> chunk_order;
@@ -326,8 +326,8 @@ read_compressed_wim_resource(const struct wim_resource_spec * const rspec,
                /* Now fill in chunk_offsets from the entries we have read in
                 * chunk_tab_data.  We break aliasing rules here to avoid having
                 * to allocate yet another array.  */
-               typedef le64 __attribute__((may_alias)) aliased_le64_t;
-               typedef le32 __attribute__((may_alias)) aliased_le32_t;
+               typedef le64 _may_alias_attribute aliased_le64_t;
+               typedef le32 _may_alias_attribute aliased_le32_t;
                u64 * chunk_offsets_p = chunk_offsets;
 
                if (alt_chunk_table) {
@@ -367,14 +367,13 @@ read_compressed_wim_resource(const struct wim_resource_spec * const rspec,
 
        /* Allocate buffer for holding the uncompressed data of each chunk.  */
        if (chunk_size <= STACK_MAX) {
-               _ubuf = alloca(chunk_size + 15);
+               ubuf = alloca(chunk_size);
        } else {
-               _ubuf = MALLOC(chunk_size + 15);
-               if (_ubuf == NULL)
+               ubuf = MALLOC(chunk_size);
+               if (ubuf == NULL)
                        goto oom;
                ubuf_malloced = true;
        }
-       ubuf = (u8 *)(((uintptr_t)_ubuf + 15) & ~15);
 
        /* Allocate a temporary buffer for reading compressed chunks, each of
         * which can be at most @chunk_size - 1 bytes.  This excludes compressed
@@ -548,7 +547,7 @@ out_free_memory:
        if (chunk_offsets_malloced)
                FREE(chunk_offsets);
        if (ubuf_malloced)
-               FREE(_ubuf);
+               FREE(ubuf);
        if (cbuf_malloced)
                FREE(cbuf);
        errno = errno_save;