[ostree] core: Add ostree checkout --compose

[Colin Walters <walters src gnome org>]

commit d23f20310810e0f182797f5a58826aafda636fe0
Author: Colin Walters <walters verbum org>
Date:   Thu Nov 3 21:50:00 2011 -0400

    core: Add ostree checkout --compose
    
    This allows merging e.g. multiple artifact trees into one big tree.

 libostree/ostree-repo.c         |    1 +
 ostree/ot-builtin-checkout.c    |  236 +++++++++++++++++++++++++++++++++++++--
 tests/t0005-checkout-compose.sh |   63 +++++++++++
 3 files changed, 288 insertions(+), 12 deletions(-)
---
diff --git a/libostree/ostree-repo.c b/libostree/ostree-repo.c
index 1b58d32..cd7b504 100644
--- a/libostree/ostree-repo.c
+++ b/libostree/ostree-repo.c
@@ -349,6 +349,7 @@ ostree_repo_resolve_rev (OstreeRepo     *self,
                          char          **sha256,
                          GError        **error)
 {
+  g_return_val_if_fail (rev != NULL, FALSE);
   return resolve_rev (self, rev, FALSE, sha256, error);
 }
 
diff --git a/ostree/ot-builtin-checkout.c b/ostree/ot-builtin-checkout.c
index 30622fd..00aaa79 100644
--- a/ostree/ot-builtin-checkout.c
+++ b/ostree/ot-builtin-checkout.c
@@ -27,12 +27,194 @@
 #include <glib/gi18n.h>
 
 static char *repo_path;
+static gboolean compose;
+
+#define FAST_QUERYINFO "standard::name,standard::type,standard::is-symlink,standard::symlink-target,unix::*"
 
 static GOptionEntry options[] = {
   { "repo", 0, 0, G_OPTION_ARG_FILENAME, &repo_path, "Repository path", "repo" },
+  { "compose", 0, 0, G_OPTION_ARG_NONE, &compose, "Extra arguments are branches to compose, in order", NULL },
   { NULL }
 };
 
+static void
+rm_rf (GFile *path)
+{
+  GFileInfo *finfo = NULL;
+  GFileEnumerator *path_enum = NULL;
+  guint32 type;
+  
+  finfo = g_file_query_info (path, FAST_QUERYINFO,
+                             G_FILE_QUERY_INFO_NOFOLLOW_SYMLINKS,
+                             NULL, NULL);
+  if (!finfo)
+    goto out;
+
+  type = g_file_info_get_attribute_uint32 (finfo, "standard::type");
+  if (type == G_FILE_TYPE_DIRECTORY)
+    {
+      path_enum = g_file_enumerate_children (path, FAST_QUERYINFO, 
+                                             G_FILE_QUERY_INFO_NOFOLLOW_SYMLINKS,
+                                             NULL, NULL);
+      if (!path_enum)
+        goto out;
+
+      
+      g_clear_object (&finfo);
+      while ((finfo = g_file_enumerator_next_file (path_enum, NULL, NULL)) != NULL)
+        {
+          GFile *child = g_file_get_child (path, g_file_info_get_attribute_byte_string (finfo, "standard::name"));
+          rm_rf (child);
+          g_clear_object (&child);
+          g_clear_object (&finfo);
+        }
+    }
+
+  (void) g_file_delete (path, NULL, NULL);
+
+ out:
+  g_clear_object (&finfo);
+  g_clear_object (&path_enum);
+}
+
+static gboolean
+merge_dir (GFile    *destination,
+           GFile    *src,
+           GError  **error)
+{
+  gboolean ret = FALSE;
+  char *dest_path = NULL;
+  char *src_path = NULL;
+  GError *temp_error = NULL;
+  GFileInfo *src_fileinfo = NULL;
+  GFileInfo *dest_fileinfo = NULL;
+  GFileEnumerator *src_enum = NULL;
+  GFile *dest_subfile = NULL;
+  GFile *src_subfile = NULL;
+  const char *name;
+  guint32 type;
+
+  dest_path = g_file_get_path (destination);
+  src_path = g_file_get_path (src);
+
+  dest_fileinfo = g_file_query_info (destination, FAST_QUERYINFO,
+                                     G_FILE_QUERY_INFO_NOFOLLOW_SYMLINKS,
+                                     NULL, &temp_error);
+  if (dest_fileinfo)
+    {
+      type = g_file_info_get_attribute_uint32 (dest_fileinfo, "standard::type");
+      if (type != G_FILE_TYPE_DIRECTORY)
+        {
+          g_set_error (error, G_IO_ERROR, G_IO_ERROR_FAILED,
+                       "Attempting to replace non-directory %s with directory %s",
+                       dest_path, src_path);
+          goto out;
+        }
+
+      src_enum = g_file_enumerate_children (src, FAST_QUERYINFO, 
+                                            G_FILE_QUERY_INFO_NOFOLLOW_SYMLINKS,
+                                            NULL, error);
+      if (!src_enum)
+        goto out;
+
+      while ((src_fileinfo = g_file_enumerator_next_file (src_enum, NULL, &temp_error)) != NULL)
+        {
+          type = g_file_info_get_attribute_uint32 (src_fileinfo, "standard::type");
+          name = g_file_info_get_attribute_byte_string (src_fileinfo, "standard::name");
+      
+          dest_subfile = g_file_get_child (destination, name);
+          src_subfile = g_file_get_child (src, name);
+
+          if (type == G_FILE_TYPE_DIRECTORY)
+            {
+              if (!merge_dir (dest_subfile, src_subfile, error))
+                goto out;
+            }
+          else
+            {
+              if (!g_file_delete (dest_subfile, NULL, &temp_error))
+                {
+                  if (g_error_matches (temp_error, G_IO_ERROR, G_IO_ERROR_NOT_FOUND))
+                    g_clear_error (&temp_error);
+                  else
+                    {
+                      g_propagate_error (error, temp_error);
+                      goto out;
+                    }
+                }
+              if (!g_file_move (src_subfile, dest_subfile, 0, NULL, NULL, NULL, error))
+                goto out;
+            }
+        }
+      if (temp_error)
+        {
+          g_propagate_error (error, temp_error);
+          goto out;
+        }
+    }
+  else if (g_error_matches (temp_error, G_IO_ERROR, G_IO_ERROR_NOT_FOUND))
+    {
+      g_clear_error (&temp_error);
+      if (!g_file_move (src, destination, 0, NULL, NULL, NULL, error))
+        goto out;
+    }
+  else
+    goto out;
+
+  ret = TRUE;
+ out:
+  g_free (dest_path);
+  g_free (src_path);
+  g_clear_object (&src_fileinfo);
+  g_clear_object (&dest_fileinfo);
+  g_clear_object (&src_enum);
+  g_clear_object (&dest_subfile);
+  g_clear_object (&src_subfile);
+  return ret;
+}
+
+static gboolean
+compose_branch_on_dir (OstreeRepo *repo,
+                       GFile *destination,
+                       const char *branch,
+                       GError **error)
+{
+  char *destpath = NULL;
+  char *branchpath = NULL;
+  GFile *branchf = NULL;
+  GFileEnumerator *enumerator = NULL;
+  gboolean ret = FALSE;
+  char *branchrev = NULL;
+
+  if (!ostree_repo_resolve_rev (repo, branch, &branchrev, error))
+    goto out;
+  
+  destpath = g_file_get_path (destination);
+  if (g_str_has_suffix (destpath, "/"))
+    destpath[strlen (destpath) - 1] = '\0';
+  branchpath = g_strconcat (destpath, "-tmp-checkout-", branchrev, NULL);
+  branchf = ot_util_new_file_for_path (branchpath);
+
+  g_print ("Checking out %s (commit %s)...\n", branch, branchrev);
+  if (!ostree_repo_checkout (repo, branchrev, branchpath, error))
+    goto out;
+  g_print ("...done\n", branch);
+  g_print ("Merging over destination...\n", branch, branchrev);
+  if (!merge_dir (destination, branchf, error))
+    goto out;
+
+  ret = TRUE;
+ out:
+  if (branchf)
+    rm_rf (branchf);
+  g_clear_object (&enumerator);
+  g_clear_object (&branchf);
+  g_free (branchrev);
+  g_free (destpath);
+  g_free (branchpath);
+  return ret;
+}
+
 gboolean
 ostree_builtin_checkout (int argc, char **argv, const char *prefix, GError **error)
 {
@@ -42,6 +224,8 @@ ostree_builtin_checkout (int argc, char **argv, const char *prefix, GError **err
   OstreeCheckout *checkout = NULL;
   const char *commit;
   const char *destination;
+  GFile *destf = NULL;
+  int i;
 
   context = g_option_context_new ("COMMIT DESTINATION - Check out a commit into a filesystem tree");
   g_option_context_add_main_entries (context, options, NULL);
@@ -56,21 +240,48 @@ ostree_builtin_checkout (int argc, char **argv, const char *prefix, GError **err
   if (!ostree_repo_check (repo, error))
     goto out;
 
-  if (argc < 3)
-    {
-      gchar *help = g_option_context_get_help (context, TRUE, NULL);
-      g_printerr ("%s\n", help);
-      g_free (help);
-      g_set_error_literal (error, G_IO_ERROR, G_IO_ERROR_FAILED,
-                           "COMMIT and DESTINATION must be specified");
-      goto out;
+  if (!compose)
+    { 
+      if (argc < 3)
+        {
+          gchar *help = g_option_context_get_help (context, TRUE, NULL);
+          g_printerr ("%s\n", help);
+          g_free (help);
+          g_set_error_literal (error, G_IO_ERROR, G_IO_ERROR_FAILED,
+                               "COMMIT and DESTINATION must be specified");
+          goto out;
+        }
+      
+      commit = argv[1];
+      destination = argv[2];
+
+      if (!ostree_repo_checkout (repo, commit, destination, error))
+        goto out;
     }
+  else
+    {
+      destination = argv[1];
 
-  commit = argv[1];
-  destination = argv[2];
+      destf = ot_util_new_file_for_path (destination);
 
-  if (!ostree_repo_checkout (repo, commit, destination, error))
-    goto out;
+      if (argc < 3)
+        {
+          gchar *help = g_option_context_get_help (context, TRUE, NULL);
+          g_printerr ("%s\n", help);
+          g_free (help);
+          g_set_error_literal (error, G_IO_ERROR, G_IO_ERROR_FAILED,
+                               "DESTINATION and at least one COMMIT must be specified");
+          goto out;
+        }
+
+      for (i = 2; i < argc; i++)
+        {
+          const char *branch = argv[i];
+
+          if (!compose_branch_on_dir (repo, destf, branch, error))
+            goto out;
+        }
+    }
 
   ret = TRUE;
  out:
@@ -78,5 +289,6 @@ ostree_builtin_checkout (int argc, char **argv, const char *prefix, GError **err
     g_option_context_free (context);
   g_clear_object (&repo);
   g_clear_object (&checkout);
+  g_clear_object (&destf);
   return ret;
 }
diff --git a/tests/t0005-checkout-compose.sh b/tests/t0005-checkout-compose.sh
new file mode 100755
index 0000000..22c0b2f
--- /dev/null
+++ b/tests/t0005-checkout-compose.sh
@@ -0,0 +1,63 @@
+#!/bin/bash
+#
+# Copyright (C) 2011 Colin Walters <walters verbum org>
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 2 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software
+# Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+#
+# Author: Colin Walters <walters verbum org>
+
+set -e
+
+echo "1..8"
+
+. libtest.sh
+
+setup_test_repository "regular"
+
+ostree checkout $ot_repo test2 checkout-test2
+
+cd "${test_tmpdir}"
+mkdir artifact-libfoo-runtime
+cd artifact-libfoo-runtime
+mkdir -p usr/lib/
+echo 'an ELF file' > usr/lib/libfoo.so
+mkdir -p usr/share
+echo 'some data' > usr/share/foo.data
+
+find | grep -v '^\.$' | ostree commit $ot_repo -b artifact-libfoo-runtime -s 'Build 12345 of libfoo' --from-stdin
+
+cd "${test_tmpdir}"
+mkdir artifact-libfoo-devel
+cd artifact-libfoo-devel
+mkdir -p usr/include
+echo 'a header' > usr/include/foo.h
+mkdir -p usr/share/doc
+echo 'some documentation' > usr/share/doc/foo.txt
+
+find | grep -v '^\.$' | ostree commit $ot_repo -b artifact-libfoo-devel -s 'Build 12345 of libfoo' --from-stdin
+
+cd "${test_tmpdir}"
+mkdir artifact-barapp
+cd artifact-barapp
+mkdir -p usr/bin
+echo 'another ELF file' > usr/bin/bar
+
+find | grep -v '^\.$' | ostree commit $ot_repo -b artifact-barapp -s 'Build 42 of barapp' --from-stdin
+
+echo 'ok artifacts committed'
+
+cd "${test_tmpdir}"
+ostree checkout $ot_repo --compose some-compose artifact-libfoo-runtime artifact-libfoo-devel artifact-barapp
+echo 'ok compose command'