From dddb449d2c099ffff5bb4f9de2ed4d2c61b4e905 Mon Sep 17 00:00:00 2001
From: Alexander Larsson <alexl@redhat.com>
Date: Fri, 11 Sep 2020 11:24:43 +0200
Subject: [PATCH] pull: Actually mmap summary files

The change in cbf1aca1d5c08d2f40832d16670484ba878d95fb actually
only mmaps the signature file, not the summary. This change makes
use mmap both, as well as extract the cache loading into a helper
function that we will later use in more places.
---
 src/libostree/ostree-repo-pull.c | 86 ++++++++++++++++++++------------
 1 file changed, 55 insertions(+), 31 deletions(-)

diff --git a/src/libostree/ostree-repo-pull.c b/src/libostree/ostree-repo-pull.c
index 0e342568..f7f34d64 100644
--- a/src/libostree/ostree-repo-pull.c
+++ b/src/libostree/ostree-repo-pull.c
@@ -2626,54 +2626,78 @@ validate_variant_is_csum (GVariant       *csum,
   return ostree_validate_structureof_csum_v (csum, error);
 }
 
+static gboolean
+_ostree_repo_load_cache_summary_file (OstreeRepo        *self,
+                                      const char        *filename,
+                                      const char        *extension,
+                                      GBytes           **out_data,
+                                      GCancellable      *cancellable,
+                                      GError           **error)
+{
+  const char *file = glnx_strjoina (_OSTREE_SUMMARY_CACHE_DIR, "/", filename, extension);
+  glnx_autofd int fd = -1;
+  g_autoptr(GBytes) data = NULL;
+
+  *out_data = NULL;
+
+  if (self->cache_dir_fd == -1)
+    return TRUE;
+
+  fd = openat (self->cache_dir_fd, file, O_CLOEXEC | O_RDONLY);
+  if (fd < 0)
+    {
+      if (errno == ENOENT)
+        return TRUE;
+      return glnx_throw_errno_prefix (error, "openat(%s)", file);
+    }
+
+  data = ot_fd_readall_or_mmap (fd, 0, error);
+  if (!data)
+    return FALSE;
+
+  *out_data =g_steal_pointer (&data);
+  return TRUE;
+}
+
 /* Load the summary from the cache if the provided .sig file is the same as the
    cached version.  */
 static gboolean
 _ostree_repo_load_cache_summary_if_same_sig (OstreeRepo        *self,
                                              const char        *remote,
                                              GBytes            *summary_sig,
-                                             GBytes            **summary,
+                                             GBytes           **out_summary,
                                              GCancellable      *cancellable,
                                              GError           **error)
 {
-  if (self->cache_dir_fd == -1)
-    return TRUE;
+  g_autoptr(GBytes) old_sig_contents = NULL;
 
-  const char *summary_cache_sig_file = glnx_strjoina (_OSTREE_SUMMARY_CACHE_DIR, "/", remote, ".sig");
-  glnx_autofd int prev_fd = -1;
-  if (!ot_openat_ignore_enoent (self->cache_dir_fd, summary_cache_sig_file, &prev_fd, error))
-    return FALSE;
-  if (prev_fd < 0)
-    return TRUE; /* Note early return */
+  *out_summary = NULL;
 
-  g_autoptr(GBytes) old_sig_contents = ot_fd_readall_or_mmap (prev_fd, 0, error);
-  if (!old_sig_contents)
+  if (!_ostree_repo_load_cache_summary_file (self, remote, ".sig",
+                                             &old_sig_contents,
+                                             cancellable, error))
     return FALSE;
 
-  if (g_bytes_compare (old_sig_contents, summary_sig) == 0)
+  if (old_sig_contents != NULL &&
+      g_bytes_compare (old_sig_contents, summary_sig) == 0)
     {
-      const char *summary_cache_file = glnx_strjoina (_OSTREE_SUMMARY_CACHE_DIR, "/", remote);
-      glnx_autofd int summary_fd = -1;
-      GBytes *summary_data;
+      g_autoptr(GBytes) summary_data = NULL;
 
-
-      summary_fd = openat (self->cache_dir_fd, summary_cache_file, O_CLOEXEC | O_RDONLY);
-      if (summary_fd < 0)
-        {
-          if (errno == ENOENT)
-            {
-              (void) unlinkat (self->cache_dir_fd, summary_cache_sig_file, 0);
-              return TRUE; /* Note early return */
-            }
-
-          return glnx_throw_errno_prefix (error, "openat(%s)", summary_cache_file);
-        }
-
-      summary_data = glnx_fd_readall_bytes (summary_fd, cancellable, error);
-      if (!summary_data)
+      if (!_ostree_repo_load_cache_summary_file (self, remote, NULL,
+                                                 &summary_data,
+                                                 cancellable, error))
         return FALSE;
-      *summary = summary_data;
+
+      if (summary_data == NULL)
+        {
+          /* Cached signature without cached summary, remove the signature */
+          const char *summary_cache_sig_file = glnx_strjoina (_OSTREE_SUMMARY_CACHE_DIR, "/", remote, ".sig");
+          (void) unlinkat (self->cache_dir_fd, summary_cache_sig_file, 0);
+        }
+      else
+        *out_summary = g_steal_pointer (&summary_data);
     }
+
   return TRUE;
 }