Add sprint_hash()

[wimlib] / src / sha1.c

diff --git a/src/sha1.c b/src/sha1.c
index bd83a413745bd0f8c8bd747517c09cad6c939a2d..9ed26fd1ebe418d36eb3f9373d4baaf255cc0139 100644 (file)
--- a/src/sha1.c
+++ b/src/sha1.c
@@ -23,6 +23,26 @@
  * mean "SHA-1 not specified".  */
 const u8 zero_hash[20];
 
+/*
+ * Builds a hexadecimal string representation of a SHA-1 message digest.
+ *
+ * The output buffer must be at least 41 characters.
+ */
+void
+sprint_hash(const u8 hash[SHA1_HASH_SIZE], tchar strbuf[SHA1_HASH_SIZE * 2 + 1])
+{
+       int i;
+       u8 high, low;
+
+       for (i = 0; i < SHA1_HASH_SIZE; i++) {
+               high = hash[i] >> 4;
+               low = hash[i] & 0xF;
+               strbuf[i * 2 + 0] = (high < 10 ? high + '0' : high - 10 + 'a');
+               strbuf[i * 2 + 1] = (low  < 10 ? low  + '0' : low  - 10 + 'a');
+       }
+       strbuf[i * 2] = 0;
+}
+
 /* If we use libcrypto (e.g. OpenSSL) then we get all the SHA-1 functions for
  * free.  Otherwise we need to implement them ourselves.  */