commit 2022ddc85f812b6990b72c7e95b8207e07ac8984
author Than McIntosh <thanm@google.com> Thu Sep 08 15:45:56 2016 -0400
committer Ian Lance Taylor <iant@golang.org> Fri Sep 09 18:23:58 2016 +0000
tree 81362703f0635e1f8fc88aa61732462772c615df
parent 4de301275dfed034a1dd9dff3d1af8643ee5cb4b

compiler: add abstraction layer for sha1 checksums.

Add new interface for the front end code to use when computing SHA1
checksums; the intent is to allow the different implementation in
different back ends.

No change in functionality for gccgo; this is an enabling change to
permit the front end to be used with other back ends (e.g. LLVM).

Change-Id: Ia9afcccc1fe4a1546cd2cdbde2e6fc79a6cea0bf
Reviewed-on: https://go-review.googlesource.com/28833
Reviewed-by: Ian Lance Taylor <iant@golang.org>

go/export.cc

diff --git a/go/export.cc b/go/export.cc
index e9040ef..bec4c7f 100644
--- a/go/export.cc
+++ b/go/export.cc
@@ -6,8 +6,7 @@
 
 #include "go-system.h"
 
-#include "sha1.h"
-
+#include "go-sha1.h"
 #include "go-c.h"
 
 #include "gogo.h"
@@ -40,6 +39,7 @@
 Export::Export(Stream* stream)
   : stream_(stream), type_refs_(), type_index_(1), packages_()
 {
+  go_assert(Export::checksum_len == Go_sha1_helper::checksum_len);
 }
 
 // A functor to sort Named_object pointers by name.
@@ -686,9 +686,8 @@
 
 Export::Stream::Stream()
 {
-  this->checksum_ = new sha1_ctx;
-  memset(this->checksum_, 0, sizeof(sha1_ctx));
-  sha1_init_ctx(this->checksum_);
+  this->sha1_helper_ = go_create_sha1_helper();
+  go_assert(this->sha1_helper_ != NULL);
 }
 
 Export::Stream::~Stream()
@@ -701,7 +700,7 @@
 void
 Export::Stream::write_and_sum_bytes(const char* bytes, size_t length)
 {
-  sha1_process_bytes(bytes, length, this->checksum_);
+  this->sha1_helper_->process_bytes(bytes, length);
   this->do_write(bytes, length);
 }
 
@@ -710,14 +709,9 @@
 std::string
 Export::Stream::checksum()
 {
-  // Use a union to provide the required alignment.
-  union
-  {
-    char checksum[Export::checksum_len];
-    long align;
-  } u;
-  sha1_finish_ctx(this->checksum_, u.checksum);
-  return std::string(u.checksum, Export::checksum_len);
+  std::string rval = this->sha1_helper_->finish();
+  delete this->sha1_helper_;
+  return rval;
 }
 
 // Write the checksum string to the export data.