SF Bugs#133: Remove the auto added map when opening the first .vik file from the...

[andy/viking.git] / src / compression.c

diff --git a/src/compression.c b/src/compression.c
index 05badab74b7401aa14bfaac3afee7ebbb674e654..291e6c2b00cb2707095a67318194fc64d3dd2bd6 100644 (file)
--- a/src/compression.c
+++ b/src/compression.c
@@ -35,6 +35,7 @@
 #endif
 
 #include "compression.h"
+#include "string.h"
 #include <gio/gio.h>
 #include <glib/gstdio.h>
 
@@ -85,6 +86,7 @@ void *unzip_file(gchar *zip_file, gulong *unzip_size)
        goto end;
 #else
        gchar *zip_data;
+       // See http://en.wikipedia.org/wiki/Zip_(file_format)
        struct _lfh {
                guint32 sig;
                guint16 extract_version;
@@ -97,12 +99,16 @@ void *unzip_file(gchar *zip_file, gulong *unzip_size)
                guint32 uncompressed_size;
                guint16 filename_len;
                guint16 extra_field_len;
-       }  __attribute__ ((__packed__)) *local_file_header = NULL;
+       }  __attribute__ ((gcc_struct,__packed__)) *local_file_header = NULL;
 
+       if ( sizeof(struct _lfh) != 30 ) {
+               g_critical ("Incorrect internal zip header size, should be 30 but is %zd", sizeof(struct _lfh) );
+               goto end;
+       }
 
        local_file_header = (struct _lfh *) zip_file;
        if (GUINT32_FROM_LE(local_file_header->sig) != 0x04034b50) {
-               g_warning("%s(): wrong format", __PRETTY_FUNCTION__);
+               g_warning("%s(): wrong format (%d)", __PRETTY_FUNCTION__, GUINT32_FROM_LE(local_file_header->sig));
                g_free(unzip_data);
                goto end;
        }
@@ -113,6 +119,23 @@ void *unzip_file(gchar *zip_file, gulong *unzip_size)
        gulong uncompressed_size = GUINT32_FROM_LE(local_file_header->uncompressed_size);
        unzip_data = g_malloc(uncompressed_size);
 
+       // Protection against malloc failures
+       // ATM not normally been checking malloc failures in Viking but sometimes using zip files can be quite large
+       //  (e.g. when using DEMs) so more potential for failure.
+       if ( !unzip_data )
+               goto end;
+
+       g_debug ("%s: method %d: from size %d to %ld", __FUNCTION__, GUINT16_FROM_LE(local_file_header->comp_method), GUINT32_FROM_LE(local_file_header->compressed_size), uncompressed_size);
+
+       if ( GUINT16_FROM_LE(local_file_header->comp_method) == 0 &&
+               (uncompressed_size == GUINT32_FROM_LE(local_file_header->compressed_size)) ) {
+               // Stored only - no need to 'uncompress'
+               // Thus just copy
+               memcpy ( unzip_data, zip_data, uncompressed_size );
+               *unzip_size = uncompressed_size;
+               goto end;
+       }
+
        if (!(*unzip_size = uncompress_data(unzip_data, uncompressed_size, zip_data, GUINT32_FROM_LE(local_file_header->compressed_size)))) {
                g_free(unzip_data);
                unzip_data = NULL;
@@ -136,7 +159,9 @@ end:
 gchar* uncompress_bzip2 ( gchar *name )
 {
 #ifdef HAVE_BZLIB_H
-       FILE *ff = g_fopen ( name, "r" );
+       g_debug ( "%s: bzip2 %s", __FUNCTION__, BZ2_bzlibVersion() );
+
+       FILE *ff = g_fopen ( name, "rb" );
        if ( !ff )
                return NULL;
 
@@ -175,7 +200,7 @@ gchar* uncompress_bzip2 ( gchar *name )
        // Process in arbitary sized chunks
        char buf[4096];
        bzerror = BZ_OK;
-       int nBuf;
+       int nBuf = 0;
        // Now process the actual compression data
        while ( bzerror == BZ_OK ) {
                nBuf = BZ2_bzRead ( &bzerror, bf, buf, 4096 );
@@ -191,12 +216,15 @@ gchar* uncompress_bzip2 ( gchar *name )
        }
        if ( bzerror != BZ_STREAM_END ) {
                // handle error...
-               g_warning ( "%s: BZ error :( %d", __FUNCTION__, bzerror );
+               g_warning ( "%s: BZ error :( %d. read %d", __FUNCTION__, bzerror, nBuf );
        }
        BZ2_bzReadClose ( &bzerror, bf );
        g_output_stream_close ( gos, NULL, &error );
 
  end:
+       g_object_unref ( gios );
+       fclose ( ff );
+
        return tmpname;
 #else
        return NULL;