initial NAMESPACE implementation

+/* GNU mailutils - a suite of utilities for electronic mail
+   Copyright (C) 1999, 2001 Free Software Foundation, 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, 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 "imap4d.h"
+
+/*FIXME: should be global? */
+typedef int (*nsfp_t) __P((void *closure, int ns, char *path, int delim));
+
+struct namespace_t
+{
+  int subdir_c;
+  char **subdir_v;
+};
+
+struct namespace_t namespace[NS_MAX];
+
+/* Note: str is not supposed to be NULL */
+int
+set_namespace(int i, char *str)
+{
+  char *p, *save;
+  struct namespace_t ns;
+  
+  /* first, estimate the number of items in subdir_v array: */
+  ns.subdir_c = 1; 
+  for (p = strchr(str, ':'); p && *p; p = strchr(p+1, ':'))
+    ns.subdir_c++;
+  
+  /* Now allocate the memory */
+  ns.subdir_v = calloc(ns.subdir_c, sizeof(ns.subdir_v[0]));
+
+  /* Fill in the array */
+  if (ns.subdir_c == 1)
+    {
+      ns.subdir_v[0] = util_normalize_path(strdup(str), "/");
+    }
+  else
+    {
+      ns.subdir_c = 0;
+      for (p = strtok_r(str, ":", &save); p; p = strtok_r(NULL, ":", &save))
+	{
+	  ns.subdir_v[ns.subdir_c++] = util_normalize_path(strdup(p), "/");
+	}
+    }
+  
+  namespace[i] = ns;
+  
+  return 0;
+}
+
+static char *
+printable_pathname(char *str)
+{
+  if (strncmp(str, homedir, strlen(homedir)) == 0)
+    {
+      str += strlen(homedir);
+      if (str[0] == '/')
+	str++;
+    }
+  return str;
+}
+
+static int
+print_namespace(int n)
+{
+  int i;
+  
+  if (namespace[n].subdir_c == 0)
+    {
+      util_send("NIL");
+      return;
+    }
+  
+  util_send("(");
+  for (i = 0; i < namespace[n].subdir_c; i++)
+    {
+      util_send("(\"%s\" \"/\")", printable_pathname(namespace[n].subdir_v[i]));
+    }
+  util_send(")");
+}
+
+int
+namespace_enumerate(int ns, nsfp_t f, void *closure)
+{
+  int i, rc;
+
+  for (i = 0; i < namespace[ns].subdir_c; i++)
+    if (rc = (*f)(closure, ns, namespace[ns].subdir_v[i], '/'))
+      return rc;
+  return 0;
+}
+
+int
+namespace_enumerate_all(nsfp_t f, void *closure)
+{
+  return namespace_enumerate(NS_PRIVATE, f, closure)
+    || namespace_enumerate(NS_OTHER, f, closure)
+    || namespace_enumerate(NS_SHARED, f, closure);
+}
+    
+int
+imap4d_namespace(struct imap4d_command *command, char *arg)
+{
+  if (! (command->states & state))
+    return util_finish (command, RESP_BAD, "Wrong state");
+  if (*arg)
+    return util_finish (command, RESP_BAD, "Too many arguments");
+
+  util_send("* NAMESPACE ");
+
+  print_namespace(NS_PRIVATE);
+  util_send(" ");
+  print_namespace(NS_OTHER);
+  util_send(" ");
+  print_namespace(NS_SHARED);
+  util_send("\r\n");
+  
+  return util_finish (command, RESP_OK, "Completed");
+}
+
+
+struct namespace_info
+{
+  char *name;
+  int  namelen;
+  int ns;
+  int exact;
+};
+
+static int
+check_namespace (void *closure, int ns, char *path, int delim)
+{
+  struct namespace_info *p = (struct namespace_info *)closure;
+  int len = strlen(path);
+  if ((len == 0 && p->namelen == len)
+      || (len > 0 && strncmp(path, p->name, strlen(path)) == 0))
+    {
+      p->ns = ns;
+      p->exact = len == p->namelen;
+      return 1;
+    }
+  return 0;
+}
+
+static int
+risky_pattern(const char *pattern, int delim)
+{
+  for (; *pattern && *pattern != delim; pattern++)
+    {
+      if (*pattern == '%' || *pattern == '*')
+	return 1;
+    }
+  return 0;
+}
+
+char *
+namespace_checkfullpath (char *name, const char *pattern, const char *delim)
+{
+  struct namespace_info info;
+  char *path = util_getfullpath(name, delim);
+
+  if (!path)
+    return path;
+
+  util_normalize_path(path, "/");
+  
+  info.name = path;
+  info.namelen = strlen(path);
+  if (!namespace_enumerate_all(check_namespace, &info))
+    {
+      free(path);
+      return NULL;
+    }
+
+  if (pattern &&
+      info.ns == NS_OTHER && info.exact && risky_pattern(pattern, '/'))
+    {
+      free(path);
+      return NULL;
+    }
+  
+  return path;
+}
+
+char *
+namespace_getfullpath (char *name, const char *delim)
+{
+  return namespace_checkfullpath (name, NULL, delim);
+}
+
+
+int
+namespace_init(char *path)
+{
+  set_namespace(NS_PRIVATE, path);
+}