From 1fabc4ecbedd1fbfaca7886cf1b34a7e9409a80b Mon Sep 17 00:00:00 2001
From: Timothy Arceri <tarceri@itsqueeze.com>
Date: Wed, 10 Feb 2021 17:05:24 +1100
Subject: [PATCH] util/mesa_sha1: add helper to reconvert sha1 hex strings

Converts the sha1 hex string representation back into its original
more compact format.

Reviewed-by: Pierre-Eric Pelloux-Prayer <pierre-eric.pelloux-prayer@amd.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/7725>
---
 src/util/mesa-sha1.c | 15 +++++++++++++++
 src/util/mesa-sha1.h |  3 +++
 2 files changed, 18 insertions(+)

diff --git a/src/util/mesa-sha1.c b/src/util/mesa-sha1.c
index fa9284627b1..410e82c7104 100644
--- a/src/util/mesa-sha1.c
+++ b/src/util/mesa-sha1.c
@@ -49,3 +49,18 @@ _mesa_sha1_format(char *buf, const unsigned char *sha1)
    }
    buf[i] = '\0';
 }
+
+/* Convert a hashs string hexidecimal representation into its more compact
+ * form.
+ */
+void
+_mesa_sha1_hex_to_sha1(unsigned char *buf, const char *hex)
+{
+   for (unsigned i = 0; i < 20; i++) {
+      char tmp[3];
+      tmp[0] = hex[i * 2];
+      tmp[1] = hex[(i * 2) + 1];
+      tmp[2] = '\0';
+      buf[i] = strtol(tmp, NULL, 16);
+   }
+}
diff --git a/src/util/mesa-sha1.h b/src/util/mesa-sha1.h
index bde50ba1eb4..9842bbb1e2d 100644
--- a/src/util/mesa-sha1.h
+++ b/src/util/mesa-sha1.h
@@ -54,6 +54,9 @@ _mesa_sha1_final(struct mesa_sha1 *ctx, unsigned char result[20])
 void
 _mesa_sha1_format(char *buf, const unsigned char *sha1);
 
+void
+_mesa_sha1_hex_to_sha1(unsigned char *buf, const char *hex);
+
 void
 _mesa_sha1_compute(const void *data, size_t size, unsigned char result[20]);