zig

commit 148fe2e99970ca880a8e10ded5af308e28bbc342 (tree)
parent 8c77c5705f41e55a5f2d80db20270d0c644338ed
Author: Andrew Kelley <superjoe30@gmail.com>
Date:   Tue, 18 Sep 2018 15:31:22 -0400

stage1 caching: don't write manifest until cache release

this prevents the situation where we determine the cache
manifest and write it, but then crash or otherwise error out
before putting the artifacts in the proper place.

now the artifacts will be in place because cache_release
happens after that step is done.

Diffstat:
M
src/cache_hash.cpp
 | 
21
+++++++++++++--------

1 file changed, 13 insertions(+), 8 deletions(-)
diff --git a/src/cache_hash.cpp b/src/cache_hash.cpp
@@ -441,18 +441,13 @@ static Error write_manifest_file(CacheHash *ch) {
 }
 
 Error cache_final(CacheHash *ch, Buf *out_digest) {
-    Error err;
-
     assert(ch->manifest_file_path != nullptr);
 
-    if (ch->manifest_dirty) {
-        if ((err = write_manifest_file(ch))) {
-            fprintf(stderr, "Warning: Unable to write cache file '%s': %s\n",
-                    buf_ptr(ch->manifest_file_path), err_str(err));
-        }
-    }
     // We don't close the manifest file yet, because we want to
     // keep it locked until the API user is done using it.
+    // We also don't write out the manifest yet, because until
+    // cache_release is called we still might be working on creating
+    // the artifacts to cache.
 
     uint8_t bin_digest[48];
     int rc = blake2b_final(&ch->blake, bin_digest, 48);
@@ -465,5 +460,15 @@ Error cache_final(CacheHash *ch, Buf *out_digest) {
 
 void cache_release(CacheHash *ch) {
     assert(ch->manifest_file_path != nullptr);
+
+    Error err;
+
+    if (ch->manifest_dirty) {
+        if ((err = write_manifest_file(ch))) {
+            fprintf(stderr, "Warning: Unable to write cache file '%s': %s\n",
+                    buf_ptr(ch->manifest_file_path), err_str(err));
+        }
+    }
+
     os_file_close(ch->manifest_file);
 }