[evolution-ews] Small cleanups to ews-oal-decompress.[ch]

[David Woodhouse <dwmw2 src gnome org>]

commit 9583a8a6d7d9a8dc4b05cae04349f134cb37c9dc
Author: David Woodhouse <David Woodhouse intel com>
Date:   Wed May 15 12:37:04 2013 +0100

    Small cleanups to ews-oal-decompress.[ch]

 src/addressbook/lzx/ews-oal-decompress.c |   82 +++++++++++++++++------------
 src/addressbook/lzx/ews-oal-decompress.h |    2 +-
 2 files changed, 49 insertions(+), 35 deletions(-)
---
diff --git a/src/addressbook/lzx/ews-oal-decompress.c b/src/addressbook/lzx/ews-oal-decompress.c
index c07d383..96872a2 100644
--- a/src/addressbook/lzx/ews-oal-decompress.c
+++ b/src/addressbook/lzx/ews-oal-decompress.c
@@ -48,17 +48,13 @@ typedef struct {
        guint32 h_version;
        guint32 l_version;
        guint32 max_block_size;
-       guint32 source_size;
        guint32 target_size;
-       guint32 source_crc;
-       guint32 target_crc;
 } LzxHeader;
 
 typedef struct {
        guint32 flags;
        guint32 comp_size;
        guint32 ucomp_size;
-       guint32 source_size;
        guint32 crc;
 } LzxBlockHeader;
 
@@ -171,7 +167,7 @@ oal_decompress_v4_full_detail_file (const gchar *filename,
        }
 
        output = fopen (output_filename, "wb");
-       if (!input) {
+       if (!output) {
                g_set_error_literal (&err, g_quark_from_string ("lzx"), 1, "unable to open the output file");
                ret = FALSE;
                goto exit;
@@ -225,14 +221,13 @@ oal_decompress_v4_full_detail_file (const gchar *filename,
                                window_bits = 25;
 
                        lzs = lzxd_init (input, output, window_bits,
-                                        0, 16, lzx_b->ucomp_size, 1);
+                                        0, 4096, lzx_b->ucomp_size, 1);
                        if (!lzs) {
                                g_set_error_literal (&err, g_quark_from_string ("lzx"), 1, "decompression 
failed (lzxd_init)");
                                ret = FALSE;
                                goto exit;
                        }
-
-                       if (lzxd_decompress (lzs, lzs->length) != LZX_ERR_OK) {
+                       if (lzxd_decompress (lzs, lzx_b->ucomp_size) != LZX_ERR_OK) {
                                g_set_error_literal (&err, g_quark_from_string ("lzx"), 1, "decompression 
failed (lzxd_decompress)");
                                ret = FALSE;
                                goto exit;
@@ -265,14 +260,33 @@ exit:
 
        return ret;
 }
-static LzxHeader *
+
+typedef struct {
+       guint32 h_version;
+       guint32 l_version;
+       guint32 max_block_size;
+       guint32 source_size;
+       guint32 target_size;
+       guint32 source_crc;
+       guint32 target_crc;
+} LzxPatchHeader;
+
+typedef struct {
+       guint32 patch_size;
+       guint32 target_size;
+       guint32 source_size;
+       guint32 crc;
+} LzxPatchBlockHeader;
+
+
+static LzxPatchHeader *
 read_patch_headers (FILE *input,
               GError **error)
 {
-       LzxHeader *lzx_h;
+       LzxPatchHeader *lzx_h;
        gboolean success;
 
-       lzx_h = g_new0 (LzxHeader, 1);
+       lzx_h = g_new0 (LzxPatchHeader, 1);
 
        success = read_uint32 (input, &lzx_h->h_version);
        if (!success)
@@ -315,20 +329,21 @@ exit:
 
        return lzx_h;
 }
-static LzxBlockHeader *
+
+static LzxPatchBlockHeader *
 read_patch_block_header (FILE *input,
                         GError **error)
 {
-       LzxBlockHeader *lzx_b;
+       LzxPatchBlockHeader *lzx_b;
        gboolean success;
 
-       lzx_b = g_new0 (LzxBlockHeader, 1);
+       lzx_b = g_new0 (LzxPatchBlockHeader, 1);
 
-       success = read_uint32 (input, &lzx_b->comp_size);
+       success = read_uint32 (input, &lzx_b->patch_size);
        if (!success)
                goto exit;
 
-       success = read_uint32 (input, &lzx_b->ucomp_size);
+       success = read_uint32 (input, &lzx_b->target_size);
        if (!success)
                goto exit;
 
@@ -352,10 +367,10 @@ exit:
 
 gboolean
 oal_apply_binpatch (const gchar *filename, const gchar *orig_filename,
-                                    const gchar *output_filename,
-                                    GError **error)
+                   const gchar *output_filename,
+                   GError **error)
 {
-       LzxHeader *lzx_h = NULL;
+       LzxPatchHeader *lzx_h = NULL;
        guint total_decomp_size = 0;
        FILE *input = NULL, *output = NULL, *orig_input = NULL;
        gboolean ret = TRUE;
@@ -370,7 +385,7 @@ oal_apply_binpatch (const gchar *filename, const gchar *orig_filename,
 
        orig_input = fopen (orig_filename, "rb");
        if (!orig_input) {
-               g_set_error_literal (&err, g_quark_from_string ("lzx"), 1, "unable to open the input file");
+               g_set_error_literal (&err, g_quark_from_string ("lzx"), 1, "unable to open the reference 
input file");
                ret = FALSE;
                goto exit;
        }
@@ -388,10 +403,9 @@ oal_apply_binpatch (const gchar *filename, const gchar *orig_filename,
                goto exit;
        }
 
-       printf("patch header: %x %x\n", lzx_h->source_size, lzx_h->target_size);
        /* TODO decompressing multiple lzx_blocks has not been tested yet. Will need to get a setup and test 
it. */
        do {
-               LzxBlockHeader *lzx_b;
+               LzxPatchBlockHeader *lzx_b;
                struct lzxd_stream *lzs;
                goffset offset;
                guint ref_size, window_bits;
@@ -404,23 +418,23 @@ oal_apply_binpatch (const gchar *filename, const gchar *orig_filename,
                }
 
                /* note the file offset */
-               offset = ftell (input);
-               
-               /* The window size should be the smallest power of two between 2^17 and 2^25 that is
-                  greater than or equal to the sum of the size of the reference data rounded up to
-                  a multiple of 32768 and the size of the subject data. Since we have no reference
-                  data, forget that and the rounding. Just the smallest power of two which is large
-                  enough to cover the subject data (lzx_b->ucomp_size). */
+               offset = ftell(input);
+
+               /* The window size should be the smallest power of two
+                  between 2^17 and 2^25 that is greater than or equal
+                  to the sum of the size of the reference data
+                  rounded up to a multiple of 32768 and the size of
+                  the subject data. */
                ref_size = (lzx_b->source_size + 32767) & ~32767;
-               window_bits = g_bit_nth_msf(ref_size + lzx_b->ucomp_size - 1, -1) + 1;
+               window_bits = g_bit_nth_msf(ref_size + lzx_b->target_size - 1, -1) + 1;
 
                if (window_bits < 17)
                        window_bits = 17;
                else if (window_bits > 25)
                        window_bits = 25;
 
-               lzs = lzxd_init (input, output,
-                                window_bits, 0, 16, lzx_b->ucomp_size, 1);
+               lzs = lzxd_init (input, output, window_bits,
+                                0, 4096, lzx_b->target_size, 1);
                if (!lzs) {
                        g_set_error_literal (&err, g_quark_from_string ("lzx"), 1, "decompression failed 
(lzxd_init)");
                        ret = FALSE;
@@ -439,10 +453,10 @@ oal_apply_binpatch (const gchar *filename, const gchar *orig_filename,
 
                /* Set the fp to beggining of next block. This is a HACK, looks like decompress reads beyond 
the block.
                 * Since we can identify the next block start from block header, we just reset the offset */
-               offset += lzx_b->comp_size;
+               offset += lzx_b->patch_size;
                fseek (input, offset, SEEK_SET);
 
-               total_decomp_size += lzx_b->ucomp_size;
+               total_decomp_size += lzx_b->target_size;
                g_free (lzx_b);
        } while (total_decomp_size < lzx_h->target_size);
 
diff --git a/src/addressbook/lzx/ews-oal-decompress.h b/src/addressbook/lzx/ews-oal-decompress.h
index dfac44b..c9b6af4 100644
--- a/src/addressbook/lzx/ews-oal-decompress.h
+++ b/src/addressbook/lzx/ews-oal-decompress.h
@@ -29,7 +29,7 @@ gboolean
 oal_decompress_v4_full_detail_file (const gchar *filename, const gchar *output_filename, GError **error);
 gboolean
 oal_apply_binpatch (const gchar *filename, const gchar *orig_filename,
-                                    const gchar *output_filename,
+                   const gchar *output_filename,
                    GError **error);
 
 #endif