+{
+ printf("Usage : minizip [-o] [-a] [-0 to -9] [-p password] file.zip [files_to_add]\n\n" \
+ " -o Overwrite existing file.zip\n" \
+ " -a Append to existing file.zip\n" \
+ " -0 Store only\n" \
+ " -1 Compress faster\n" \
+ " -9 Compress better\n\n");
+}
+
+/* calculate the CRC32 of a file,
+ because to encrypt a file, we need known the CRC32 of the file before */
+int getFileCrc(const char* filenameinzip,void*buf,unsigned long size_buf,unsigned long* result_crc)
+{
+ unsigned long calculate_crc=0;
+ int err=ZIP_OK;
+ FILE * fin = fopen(filenameinzip,"rb");
+ unsigned long size_read = 0;
+ unsigned long total_read = 0;
+ if (fin==NULL)
+ {
+ err = ZIP_ERRNO;
+ }
+
+ if (err == ZIP_OK)
+ do
+ {
+ err = ZIP_OK;
+ size_read = (int)fread(buf,1,size_buf,fin);
+ if (size_read < size_buf)
+ if (feof(fin)==0)
+ {
+ printf("error in reading %s\n",filenameinzip);
+ err = ZIP_ERRNO;
+ }
+
+ if (size_read>0)
+ calculate_crc = crc32(calculate_crc,buf,size_read);
+ total_read += size_read;
+
+ } while ((err == ZIP_OK) && (size_read>0));
+
+ if (fin)
+ fclose(fin);
+
+ *result_crc=calculate_crc;
+ printf("file %s crc %x\n",filenameinzip,calculate_crc);
+ return err;