1 files changed, 117 insertions, 0 deletions
diff --git a/helper/checksum.c b/helper/checksum.c
new file mode 100644
index 0000000..337134c
--- /dev/null
+++ b/helper/checksum.c
@@ -0,0 +1,117 @@
+/* febootstrap-supermin-helper reimplementation in C.
+ * Copyright (C) 2009-2010 Red Hat Inc.
+ *
+ * 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., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include <config.h>
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <errno.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <assert.h>
+
+#include "error.h"
+
+#include "helper.h"
+
+static FILE *pp = NULL;
+
+/* This is the command we run to calculate the SHA.  Note that we sort
+ * the rows first so that the checksum is roughly stable, since the
+ * order that we output files might not be (eg. because we rely on the
+ * ordering of readdir).  Uncomment the second line to see the output
+ * before hashing.
+ */
+static const char *shacmd = "sort | sha256sum | awk '{print $1}'";
+//static const char *shacmd = "sort | cat";
+
+static void
+checksum_start (const char *hostcpu, const char *appliance,
+                const char *modpath, const char *initrd)
+{
+  pp = popen (shacmd, "w");
+  if (pp == NULL)
+    error (EXIT_FAILURE, errno, "popen: command failed: %s", shacmd);
+
+  fprintf (pp, "%s %s %s %d\n",
+           PACKAGE_STRING, hostcpu, modpath, geteuid ());
+}
+
+static void
+checksum_end (void)
+{
+  if (pclose (pp) == -1)
+    error (EXIT_FAILURE, errno, "pclose: command failed: %s", shacmd);
+  pp = NULL;
+}
+
+static void
+checksum_file_stat (const char *filename, const struct stat *statbuf)
+{
+  /* Publically writable directories (ie. /tmp) don't have stable
+   * times.  Since we only care about some attributes of directories
+   * in any case, we vary the output accordingly.
+   */
+  if (!S_ISDIR (statbuf->st_mode))
+    fprintf (pp, "%s %ld %ld %d %d %ld %o\n",
+             filename,
+             (long) statbuf->st_ctime, (long) statbuf->st_mtime,
+             statbuf->st_uid, statbuf->st_gid, statbuf->st_size,
+             statbuf->st_mode);
+  else
+    fprintf (pp, "%s %d %d %o\n",
+             filename,
+             statbuf->st_uid, statbuf->st_gid,
+             statbuf->st_mode);
+}
+
+static void
+checksum_file (const char *filename)
+{
+  struct stat statbuf;
+
+  if (lstat (filename, &statbuf) == -1)
+    error (EXIT_FAILURE, errno, "lstat: %s", filename);
+  checksum_file_stat (filename, &statbuf);
+}
+
+static void
+checksum_fts_entry (FTSENT *entry)
+{
+  if (entry->fts_info & FTS_NS || entry->fts_info & FTS_NSOK)
+    checksum_file (entry->fts_path);
+  else
+    checksum_file_stat (entry->fts_path, entry->fts_statp);
+}
+
+static void
+checksum_cpio_file (const char *cpio_file)
+{
+  checksum_file (cpio_file);
+}
+
+struct writer checksum_writer = {
+  .wr_start = checksum_start,
+  .wr_end = checksum_end,
+  .wr_file = checksum_file,
+  .wr_file_stat = checksum_file_stat,
+  .wr_fts_entry = checksum_fts_entry,
+  .wr_cpio_file = checksum_cpio_file,
+};