1 files changed, 124 insertions, 0 deletions
diff --git a/src/libutil/hash.cc b/src/libutil/hash.cc
new file mode 100644
index 000000000..752b26912
--- /dev/null
+++ b/src/libutil/hash.cc
@@ -0,0 +1,124 @@
+#include <iostream>
+
+extern "C" {
+#include "md5.h"
+}
+
+#include "hash.hh"
+#include "archive.hh"
+
+
+Hash::Hash()
+{
+    memset(hash, 0, sizeof(hash));
+}
+
+
+bool Hash::operator == (const Hash & h2) const
+{
+    for (unsigned int i = 0; i < hashSize; i++)
+        if (hash[i] != h2.hash[i]) return false;
+    return true;
+}
+
+
+bool Hash::operator != (const Hash & h2) const
+{
+    return !(*this == h2);
+}
+
+
+bool Hash::operator < (const Hash & h) const
+{
+    for (unsigned int i = 0; i < hashSize; i++) {
+        if (hash[i] < h.hash[i]) return true;
+        if (hash[i] > h.hash[i]) return false;
+    }
+    return false;
+}
+
+
+Hash::operator string() const
+{
+    ostringstream str;
+    for (unsigned int i = 0; i < hashSize; i++) {
+        str.fill('0');
+        str.width(2);
+        str << hex << (int) hash[i];
+    }
+    return str.str();
+}
+
+    
+Hash parseHash(const string & s)
+{
+    Hash hash;
+    if (s.length() != Hash::hashSize * 2)
+        throw Error(format("invalid hash `%1%'") % s);
+    for (unsigned int i = 0; i < Hash::hashSize; i++) {
+        string s2(s, i * 2, 2);
+        if (!isxdigit(s2[0]) || !isxdigit(s2[1])) 
+            throw Error(format("invalid hash `%1%'") % s);
+        istringstream str(s2);
+        int n;
+        str >> hex >> n;
+        hash.hash[i] = n;
+    }
+    return hash;
+}
+
+
+bool isHash(const string & s)
+{
+    if (s.length() != 32) return false;
+    for (int i = 0; i < 32; i++) {
+        char c = s[i];
+        if (!((c >= '0' && c <= '9') ||
+              (c >= 'a' && c <= 'f')))
+            return false;
+    }
+    return true;
+}
+
+
+Hash hashString(const string & s)
+{
+    Hash hash;
+    md5_buffer(s.c_str(), s.length(), hash.hash);
+    return hash;
+}
+
+
+Hash hashFile(const Path & path)
+{
+    Hash hash;
+    FILE * file = fopen(path.c_str(), "rb");
+    if (!file)
+        throw SysError(format("file `%1%' does not exist") % path);
+    int err = md5_stream(file, hash.hash);
+    fclose(file);
+    if (err) throw SysError(format("cannot hash file `%1%'") % path);
+    return hash;
+}
+
+
+struct HashSink : DumpSink
+{
+    struct md5_ctx ctx;
+    virtual void operator ()
+        (const unsigned char * data, unsigned int len)
+    {
+        md5_process_bytes(data, len, &ctx);
+    }
+};
+
+
+Hash hashPath(const Path & path)
+{
+    Hash hash;
+    HashSink sink;
+    md5_init_ctx(&sink.ctx);
+    dumpPath(path, sink);
+    md5_finish_ctx(&sink.ctx, hash.hash);
+    return hash;
+}