util-vserver-0.30.208

[util-vserver.git] / lib / getvserverctx.c

diff --git a/lib/getvserverctx.c b/lib/getvserverctx.c
new file mode 100644 (file)
index 0000000..ce116ae
--- /dev/null
+++ b/lib/getvserverctx.c
@@ -0,0 +1,156 @@
+// $Id: getvserverctx.c,v 1.8 2004/06/27 13:02:07 ensc Exp $    --*- c -*--
+
+// Copyright (C) 2003 Enrico Scholz <enrico.scholz@informatik.tu-chemnitz.de>
+//  
+// 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; version 2 of the License.
+//  
+// 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.
+
+
+#ifdef HAVE_CONFIG_H
+#  include <config.h>
+#endif
+
+#include "vserver.h"
+#include "pathconfig.h"
+#include "compat-c99.h"
+#include "lib_internal/util.h"
+
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <errno.h>
+#include <string.h>
+#include <unistd.h>
+
+#ifdef VC_ENABLE_API_COMPAT
+#include <fcntl.h>
+
+static xid_t
+extractLegacyXID(char const *dir, char const *basename)
+{
+  size_t       l1 = strlen(dir);
+  size_t       l2 = strlen(basename);
+  char         path[l1 + l2 + sizeof("/.ctx")];
+  char *       ptr = path;
+  int          fd;
+  ssize_t      len;
+  xid_t                result = VC_NOXID;
+
+  ptr    = Xmemcpy(ptr, dir, l1);
+  *ptr++ = '/';
+  ptr    = Xmemcpy(ptr, basename, l2);
+  ptr    = Xmemcpy(ptr, ".ctx",    5);
+
+  fd = open(path, O_RDONLY);
+  if (fd==-1) return VC_NOXID;
+
+  len = lseek(fd, 0, SEEK_END);
+
+  if (len!=-1 && lseek(fd, 0, SEEK_SET)!=-1) {
+    char       buf[len+2];
+    char const *pos = 0;
+
+    buf[0] = '\n';
+    
+    if (read(fd, buf+1, len+1)==len) {
+      buf[len+1] = '\0';
+      pos        = strstr(buf, "\nS_CONTEXT=");
+    }
+
+    if (pos) pos += 11;
+    if (*pos>='1' && *pos<='9')
+      result = atoi(pos);
+  }
+
+  close(fd);
+  return result;
+}
+#else
+static xid_t
+extractLegacyXID(char const UNUSED *dir, char const UNUSED *basename)
+{
+  return VC_NOXID;
+}
+#endif
+
+
+static xid_t
+getCtxFromFile(char const *pathname)
+{
+  int          fd;
+  off_t                len;
+
+  fd = open(pathname, O_RDONLY);
+
+  if (fd==-1 ||
+      (len=lseek(fd, 0, SEEK_END))==-1 ||
+      (len>50) ||
+      (lseek(fd, 0, SEEK_SET)==-1))
+    return VC_NOCTX;
+
+  {
+  char         buf[len+1];
+  char         *errptr;
+  xid_t                res;
+  
+  if (TEMP_FAILURE_RETRY(read(fd, buf, len+1))!=len)
+    return VC_NOCTX;
+
+  res = strtol(buf, &errptr, 10);
+  if (*errptr!='\0' && *errptr!='\n') return VC_NOCTX;
+
+  return res;
+  }
+}
+
+xid_t
+vc_getVserverCtx(char const *id, vcCfgStyle style, bool honor_static, bool *is_running)
+{
+  size_t               l1 = strlen(id);
+  char                 buf[sizeof(CONFDIR "//") + l1 + sizeof("/context")];
+                           
+  if (style==vcCFG_NONE || style==vcCFG_AUTO)
+    style = vc_getVserverCfgStyle(id);
+
+  if (is_running) *is_running = false;
+
+  switch (style) {
+    case vcCFG_NONE            :  return VC_NOCTX;
+    case vcCFG_LEGACY          :
+      return extractLegacyXID(DEFAULT_PKGSTATEDIR, id);
+    case vcCFG_RECENT_SHORT    :
+    case vcCFG_RECENT_FULL     : {
+      size_t           idx = 0;
+      xid_t            res = 0;
+
+      if (style==vcCFG_RECENT_SHORT) {
+       memcpy(buf, CONFDIR "/", sizeof(CONFDIR "/")-1);
+       idx  = sizeof(CONFDIR "/") - 1;
+      }
+      memcpy(buf+idx, id, l1);    idx += l1;
+      memcpy(buf+idx, "/run", 5);      // appends '\0' too
+      
+      res = getCtxFromFile(buf);
+      if (is_running) *is_running = res!=VC_NOCTX;
+      
+      if (res==VC_NOCTX && honor_static) {
+       memcpy(buf+idx, "/context", 9); // appends '\0' too
+
+       res = getCtxFromFile(buf);
+      }
+      
+      return res;
+    }
+    default                    :  return VC_NOCTX;
+  }
+}