introduce incremental md5 digester

Signed-off-by: Michael Krelin <hacker@klever.net>

1 files changed, 14 insertions, 0 deletions

diff --git a/src/eyetil.cc b/src/eyetil.cc
index 7669cb6..57ae607 100644
--- a/src/eyetil.cc
+++ b/src/eyetil.cc
@@ -25,96 +25,110 @@ binary_t& binary_t::from_hex(const std::string& h) {
     char t[3] = { 0,0,0 };
     for(int i=0;i<rvs;++i) {
 	t[0]=*(hp++); t[1]=*(hp++);
 	*(oi++) = strtol(t,0,16);
     }
     return *this;
 }
 
 binary_t& binary_t::from_data(const void *d,size_t s) {
     resize(s);
     std::copy((const unsigned char*)d,(const unsigned char *)d+s,
 	    begin() );
     return *this;
 }
 
 binary_t& binary_t::make_nonce() {
 #ifdef HAVE_LIBUUID
     uuid_t uuid;
     uuid_generate(uuid);
     from_data((unsigned char*)uuid,sizeof(uuid));
 #else
     resize(16);
     std::generate_n(begin(),16,rand);
 #endif /* HAVE_LIBUUID */
     return *this;
 }
 
 std::string binary_t::hex() const {
     std::string rv;
     rv.reserve((size()<<1)+1);
     char t[3] = {0,0,0};
     for(const_iterator i=begin(),ie=end();i!=ie;++i) {
 	int rc = snprintf(t,sizeof(t),"%02x",*i);
 	assert(rc<sizeof(t));
 	rv += t;
     }
     return rv;
 }
 
 binary_t binary_t::md5() const {
     binary_t rv(MD5_DIGEST_LENGTH);
     if(!MD5(
 		(const unsigned char*)&(front()),size(),
 		(unsigned char*)&(rv.front()) ))
 	throw std::runtime_error("failed to md5()");
     return rv;
 }
 
+void md5_digester::init() {
+    if(!MD5_Init(&ctx)) throw std::runtime_error("failed to MD5_Init()");
+}
+void md5_digester::update(const void *d,size_t l) {
+    if(!MD5_Update(&ctx,d,l)) throw std::runtime_error("failed to MD5_Update()");
+}
+binary_t md5_digester::final() {
+    binary_t rv(MD5_DIGEST_LENGTH);
+    if(!MD5_Final((unsigned char*)&(rv.front()), &ctx))
+	throw std::runtime_error("failed to MD5_Final()");
+    return rv;
+}
+
+
 static void make_path_for_template(const std::string& p,mode_t m) {
     struct stat st;
     std::string pp;
     for(std::string::size_type sl=p.find('/',1);
 	    sl!=std::string::npos;
 	    sl=p.find('/',sl+1)) {
 	if(stat( (pp=p.substr(0,sl)).c_str() ,&st)
 		|| !S_ISDIR(st.st_mode)) {
 	    if(mkdir(pp.c_str(),m))
 		throw std::runtime_error("failed to mkdir()");
 	}
     }
 }
 
 tmpdir_t::tmpdir_t(const std::string& dt) : dir(dt) {
     make_path_for_template(dt,0777);
     if(!mkdtemp((char*)dir.data()))
 	throw std::runtime_error("failed to mkdtmp()");
 }
 tmpdir_t::~tmpdir_t() {
     assert(!dir.empty());
     if(rmdir(dir.c_str())) {
 	syslog(LOG_WARNING,"Failed to remove '%s' directory",dir.c_str());
     }
 }
 
 std::string tmpdir_t::get_file(const std::string& f) {
     std::string::size_type ls = f.rfind('/');
     return dir+'/'+(
 	    (ls==std::string::npos)
 	    ? f
 	    : f.substr(ls+1)
 	);
 }
 
 tarchive_t::tarchive_t(void *p,size_t s) : a(archive_read_new()), e(0) {
     if(!a) throw std::runtime_error("failed to archive_read_new()");
     if(archive_read_support_format_tar(a)) {
 	archive_read_finish(a);
 	throw std::runtime_error("failed to archive_read_support_format_tar()");
     }
     if(archive_read_open_memory(a,p,s)) {
 	archive_read_finish(a);
 	throw std::runtime_error("failed to archive_read_open_memory()");
     }
 }
 tarchive_t::~tarchive_t() {
     assert(a);