From: David Bremner <david@tethera.net>
Date: Sun, 24 Nov 2013 12:40:13 +0000 (+2000)
Subject: Re: notmuch sha1 implementation broken on (some) big-endian architectures
X-Git-Url: http://git.tremily.us/?a=commitdiff_plain;h=ad18af0165900c938b1dc327da1b6e75fecc98f5;p=notmuch-archives.git

Re: notmuch sha1 implementation broken on (some) big-endian architectures
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+From: David Bremner <david@tethera.net>
+To: notmuch@notmuchmail.org
+Subject: Re: notmuch sha1 implementation broken on (some) big-endian
+	architectures
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+Date: Sun, 24 Nov 2013 08:40:13 -0400
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+
+David Bremner <david@tethera.net> writes:
+
+> The following code, when linked with libnotmuch.a and libutil.a does a
+> passable imitation of sha1sum on amd64 (and I guess also i386) but
+> computes a different digest on powerpc and probably sparc and s390x.
+>
+> In the long run we should maybe outsource hash computations to
+> e.g. librhash, but I'd like a simpler fix for 0.17, if possible
+
+Out of curiousity, I tried out a similar example with librhash, and it
+works fine on powerpc.
+
+#include <errno.h>
+#include "rhash.h" /* LibRHash interface */
+
+int main(int argc, char *argv[])
+{
+  char digest[64];
+  char output[130];
+
+  rhash_library_init(); /* initialize static data */
+
+  int res = rhash_file(RHASH_SHA1, argv[1], digest);
+  if(res < 0) {
+    fprintf(stderr, "LibRHash error: %s: %s\n", argv[1], strerror(errno));
+    return 1;
+  }
+
+  /* convert binary digest to hexadecimal string */
+  rhash_print_bytes(output, digest, rhash_get_digest_size(RHASH_SHA1),RHPR_HEX);
+
+  printf("%s (%s) = %s\n", rhash_get_name(RHASH_SHA1), argv[1], output);
+  return 0;
+}