common: Add mkdir_p.

* common/mkdir_p.c: New file.
* common/mkdir_p.h: New file.
* common/Makefile.am (common_sources): Add mkdir_p.c and mkdir_p.h.

--
Signed-off-by: Neal H. Walfield <neal@g10code.com>.

common/Makefile.am

@@ -86,7 +86,8 @@ common_sources = \
 	openpgp-oid.c \
 	ssh-utils.c ssh-utils.h \
 	agent-opt.c \
-	helpfile.c
+	helpfile.c \
+	mkdir_p.c mkdir_p.h
 
 if HAVE_W32_SYSTEM
 common_sources += w32-reg.c w32-afunix.c w32-afunix.h

common/mkdir_p.c

@@ -0,0 +1,161 @@
+/* mkdir_p.c - Create a directory and any missing parents.
+ * Copyright (C) 2015 g10 Code GmbH
+ *
+ * This file is part of GnuPG.
+ *
+ * GnuPG 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 3 of the License, or
+ * (at your option) any later version.
+ *
+ * GnuPG 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, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <config.h>
+#include <sys/stat.h>
+#include <errno.h>
+#include <assert.h>
+#include <stdarg.h>
+
+#include "mkdir_p.h"
+#include "stringhelp.h"
+#include "logging.h"
+#include "util.h"
+
+#define DEBUG 0
+
+int
+amkdir_p (char **directory_components)
+{
+  int count;
+  char **dirs;
+  int i;
+  int rc;
+
+  for (count = 0; directory_components[count]; count ++)
+    ;
+
+  if (DEBUG)
+    log_debug ("%s: %d directory components.\n", __func__, count);
+
+  dirs = xcalloc (count, sizeof (char *));
+  for (i = 0; directory_components[i]; i ++)
+    {
+      if (i == 0)
+	dirs[i] = directory_components[i];
+      else
+	dirs[i] = make_filename (dirs[i - 1], directory_components[i], NULL);
+
+      if (DEBUG)
+	log_debug ("%s: Directory %d: `%s'.\n", __func__, i, dirs[i]);
+    }
+
+  for (i = count - 1; i >= 0; i --)
+    {
+      struct stat s;
+
+      if (DEBUG)
+	log_debug ("%s: stat(%s)\n", __func__, dirs[i]);
+
+      rc = stat (dirs[i], &s);
+      if (rc == 0 && ! S_ISDIR (s.st_mode))
+	{
+	  if (DEBUG)
+	    log_debug ("%s: %s exists, but is not a directory!\n",
+		       __func__, dirs[i]);
+	  rc = gpg_error (GPG_ERR_ENOTDIR);
+	  goto out;
+	}
+      else if (rc == 0)
+	{
+	  /* Got a directory.  */
+	  if (DEBUG)
+	    log_debug ("%s: %s exists and is a directory!\n",
+		       __func__, dirs[i]);
+	  break;
+	}
+      else if (errno == ENOENT)
+	/* This directory does not exist yet.  Continue walking up the
+	   hierarchy.  */
+	{
+	  if (DEBUG)
+	    log_debug ("%s: %s does not exist!\n",
+		       __func__, dirs[i]);
+	  continue;
+	}
+      else
+	/* Some other error code.  Die.  Note: this could be ENOTDIR
+	   (we return this above), which means that a component of the
+	   path prefix is not a directory.  */
+	{
+	  if (DEBUG)
+	    log_debug ("%s: stat(%s) => %s!\n",
+		       __func__, dirs[i], strerror (errno));
+	  rc = gpg_error_from_syserror ();
+	  goto out;
+	}
+    }
+
+  assert (i >= -1);
+  /* DIRS[I] exists.  Start with the following entry.  */
+  i ++;
+
+  for (; i < count; i ++)
+    {
+      if (DEBUG)
+	log_debug ("Creating directory: %s\n", dirs[i]);
+
+      rc = mkdir (dirs[i], S_IRUSR | S_IWUSR | S_IXUSR);
+      if (rc)
+	{
+	  rc = gpg_error_from_syserror ();
+	  goto out;
+	}
+    }
+
+ out:
+  for (i = 1; i < count; i ++)
+    xfree (dirs[i]);
+  xfree (dirs);
+
+  if (DEBUG)
+    log_debug ("%s: Returning %s\n", __func__, gpg_strerror (rc));
+
+  return rc;
+}
+
+int
+mkdir_p (char *directory_component, ...)
+{
+  va_list ap;
+  int i;
+  int space = 1;
+  char **dirs = xmalloc (space * sizeof (char *));
+  int rc;
+
+  dirs[0] = directory_component;
+
+  va_start (ap, directory_component);
+  for (i = 1; dirs[i - 1]; i ++)
+    {
+      if (i == space)
+	{
+	  space = 2 * space;
+	  dirs = xrealloc (dirs, space * sizeof (char *));
+	}
+      dirs[i] = va_arg (ap, char *);
+    }
+  va_end (ap);
+
+  rc = amkdir_p (dirs);
+
+  xfree (dirs);
+
+  return rc;
+}

common/mkdir_p.h

@@ -0,0 +1,42 @@
+/* mkdir_p.h - Create a directory and any missing parents.
+ * Copyright (C) 2015 g10 Code GmbH
+ *
+ * This file is part of GnuPG.
+ *
+ * GnuPG 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 3 of the License, or
+ * (at your option) any later version.
+ *
+ * GnuPG 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, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef MKDIR_P_H
+#define MKDIR_P_H
+
+#include "types.h"
+
+/* Create a directory as well as any missing parents.
+
+   The arguments must be NULL termianted.  If DIRECTORY_COMPONENTS...
+   consists of two elements, "foo/bar" and "xyzzy", this function will
+   first try to create the directory "foo/bar" and then the directory
+   "foo/bar/xyzzy".  On success returns 0, otherwise an error code is
+   returned.  */
+int mkdir_p (char *directory_component, ...) GPGRT_ATTR_SENTINEL(0);
+
+/* Like mkdir_p, but DIRECTORY_COMPONENTS is a NULL terminated
+   array, e.g.:
+
+     char **dirs = { "foo", "bar", NULL };
+     amkdir_p (dirs);
+ */
+int amkdir_p (char **directory_components);
+
+#endif