[ostree] prune: add --delete-commit

[Giuseppe Scrivano <gscrivano src gnome org>]

commit 0aa836c20557f6360b3f82eb0d523916da9e8f63
Author: Giuseppe Scrivano <gscrivan redhat com>
Date:   Thu Nov 5 13:28:37 2015 +0100

    prune: add --delete-commit
    
    Signed-off-by: Giuseppe Scrivano <gscrivan redhat com>

 doc/ostree-prune.xml          |    8 ++++++++
 src/ostree/ot-builtin-fsck.c  |   14 ++------------
 src/ostree/ot-builtin-prune.c |   38 ++++++++++++++++++++++++++++++++++++++
 src/ostree/ot-main.c          |   21 +++++++++++++++++++++
 src/ostree/ot-main.h          |    2 ++
 5 files changed, 71 insertions(+), 12 deletions(-)
---
diff --git a/doc/ostree-prune.xml b/doc/ostree-prune.xml
index 523b722..91caa81 100644
--- a/doc/ostree-prune.xml
+++ b/doc/ostree-prune.xml
@@ -82,6 +82,14 @@ Boston, MA 02111-1307, USA.
             </varlistentry>
 
             <varlistentry>
+                <term><option>--delete-commit</option>=COMMIT</term>
+
+                <listitem><para>
+                    Specify a COMMIT to delete.
+                </para></listitem>
+            </varlistentry>
+
+            <varlistentry>
                 <term><option>--depth</option>=DEPTH</term>
 
                 <listitem><para>
diff --git a/src/ostree/ot-builtin-fsck.c b/src/ostree/ot-builtin-fsck.c
index d16ead8..b192683 100644
--- a/src/ostree/ot-builtin-fsck.c
+++ b/src/ostree/ot-builtin-fsck.c
@@ -310,18 +310,8 @@ ostree_builtin_fsck (int argc, char **argv, GCancellable *cancellable, GError **
       guint i;
       if (tombstones->len)
         {
-          GError *temp_error = NULL;
-          gboolean tombstone_commits = FALSE;
-          GKeyFile *config = ostree_repo_get_config (repo);
-          tombstone_commits = g_key_file_get_boolean (config, "core", "tombstone-commits", &temp_error);
-          /* tombstone_commits is FALSE either if it is not found or it is really set to FALSE in the config 
file.  */
-          if (!tombstone_commits)
-            {
-              g_clear_error (&temp_error);
-              g_key_file_set_boolean (config, "core", "tombstone-commits", TRUE);
-              if (!ostree_repo_write_config (repo, config, error))
-                goto out;
-            }
+          if (!ot_enable_tombstone_commits (repo, error))
+            goto out;
         }
       for (i = 0; i < tombstones->len; i++)
         {
diff --git a/src/ostree/ot-builtin-prune.c b/src/ostree/ot-builtin-prune.c
index 571d1a1..44868a1 100644
--- a/src/ostree/ot-builtin-prune.c
+++ b/src/ostree/ot-builtin-prune.c
@@ -25,15 +25,18 @@
 #include "ot-main.h"
 #include "ot-builtins.h"
 #include "ostree.h"
+#include "otutil.h"
 
 static gboolean opt_no_prune;
 static gint opt_depth = -1;
 static gboolean opt_refs_only;
+static char *opt_delete_commit;
 
 static GOptionEntry options[] = {
   { "no-prune", 0, 0, G_OPTION_ARG_NONE, &opt_no_prune, "Only display unreachable objects; don't delete", 
NULL },
   { "refs-only", 0, 0, G_OPTION_ARG_NONE, &opt_refs_only, "Only compute reachability via refs", NULL },
   { "depth", 0, 0, G_OPTION_ARG_INT, &opt_depth, "Only traverse DEPTH parents for each commit (default: 
-1=infinite)", "DEPTH" },
+  { "delete-commit", 0, 0, G_OPTION_ARG_STRING, &opt_delete_commit, "Specify a commit to delete", "COMMIT" },
   { NULL }
 };
 
@@ -57,6 +60,41 @@ ostree_builtin_prune (int argc, char **argv, GCancellable *cancellable, GError *
   if (!opt_no_prune && !ostree_ensure_repo_writable (repo, error))
     goto out;
 
+  if (opt_delete_commit)
+    {
+      g_autoptr(GHashTable) refs = NULL;
+      GHashTableIter hashiter;
+      gpointer hashkey, hashvalue;
+
+      if (opt_no_prune)
+        {
+          ot_util_usage_error (context, "Cannot specify both --delete-commit and --no-prune", error);
+          goto out;
+        }
+
+      if (!ostree_repo_list_refs (repo, NULL, &refs, cancellable, error))
+        goto out;
+
+      g_hash_table_iter_init (&hashiter, refs);
+      while (g_hash_table_iter_next (&hashiter, &hashkey, &hashvalue))
+        {
+          const char *ref = hashkey;
+          const char *commit = hashvalue;
+          if (g_strcmp0 (commit, opt_delete_commit) == 0)
+            {
+              g_set_error (error, G_IO_ERROR, G_IO_ERROR_FAILED,
+                           "Commit '%s' is referenced by '%s'", opt_delete_commit, ref);
+              goto out;
+            }
+        }
+
+      if (!ot_enable_tombstone_commits (repo, error))
+        goto out;
+
+      if (!ostree_repo_delete_object (repo, OSTREE_OBJECT_TYPE_COMMIT, opt_delete_commit, cancellable, 
error))
+        goto out;
+    }
+
   if (opt_refs_only)
     pruneflags |= OSTREE_REPO_PRUNE_FLAGS_REFS_ONLY;
   if (opt_no_prune)
diff --git a/src/ostree/ot-main.c b/src/ostree/ot-main.c
index d3a7fd4..44e1bd4 100644
--- a/src/ostree/ot-main.c
+++ b/src/ostree/ot-main.c
@@ -419,3 +419,24 @@ ostree_print_gpg_verify_result (OstreeGpgVerifyResult *result)
   g_print ("%s", buffer->str);
   g_string_free (buffer, TRUE);
 }
+
+gboolean
+ot_enable_tombstone_commits (OstreeRepo *repo, GError **error)
+{
+  gboolean ret = FALSE;
+  gboolean tombstone_commits = FALSE;
+  GKeyFile *config = ostree_repo_get_config (repo);
+
+  tombstone_commits = g_key_file_get_boolean (config, "core", "tombstone-commits", NULL);
+  /* tombstone_commits is FALSE either if it is not found or it is really set to FALSE in the config file.  
*/
+  if (!tombstone_commits)
+    {
+      g_key_file_set_boolean (config, "core", "tombstone-commits", TRUE);
+      if (!ostree_repo_write_config (repo, config, error))
+        goto out;
+    }
+
+  ret = TRUE;
+ out:
+  return ret;
+}
diff --git a/src/ostree/ot-main.h b/src/ostree/ot-main.h
index d893b73..32620c5 100644
--- a/src/ostree/ot-main.h
+++ b/src/ostree/ot-main.h
@@ -63,3 +63,5 @@ gboolean ostree_admin_option_context_parse (GOptionContext *context,
 gboolean ostree_ensure_repo_writable (OstreeRepo *repo, GError **error);
 
 void ostree_print_gpg_verify_result (OstreeGpgVerifyResult *result);
+
+gboolean ot_enable_tombstone_commits (OstreeRepo *repo, GError **error);