1 files changed, 116 insertions, 0 deletions
diff --git a/library/namespace.c b/library/namespace.c
new file mode 100644
index 0000000..04e4c45
--- /dev/null
+++ b/library/namespace.c
@@ -0,0 +1,116 @@
+/*
+ * namespace.c - Library API for Linux namespaces
+ *
+ * Copyright © 2015-2023 Jim Warner <james.warner@comcast.net>
+ * Copyright © 2015-2023 Craig Small <csmall@dropbear.xyz>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library 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
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+ */
+
+#include <errno.h>
+#include <stdio.h>
+#include <string.h>
+#include <sys/stat.h>
+
+#include "misc.h"
+#include "procps-private.h"
+
+#define NSPATHLEN 64
+
+static const char *ns_names[] = {
+    [PROCPS_NS_CGROUP] = "cgroup",
+    [PROCPS_NS_IPC]    = "ipc",
+    [PROCPS_NS_MNT]    = "mnt",
+    [PROCPS_NS_NET]    = "net",
+    [PROCPS_NS_PID]    = "pid",
+    [PROCPS_NS_TIME]   = "time",
+    [PROCPS_NS_USER]   = "user",
+    [PROCPS_NS_UTS]    = "uts"
+};
+
+
+/*
+ * procps_ns_get_name:
+ *
+ * Find the name of the namespace with the given ID
+ *
+ * @id: The ID of the required namespace, see
+ * namespace_type
+ *
+ * Returns: static string of the namespace
+ */
+PROCPS_EXPORT const char *procps_ns_get_name(const int id)
+{
+    if (id >= PROCPS_NS_COUNT || id < 0)
+        return NULL;
+    return ns_names[id];
+}
+
+/*
+ * procps_ns_get_id:
+ *
+ * Find the namespace ID that matches the given
+ * name.
+ *
+ * @name: the name of the required namespace
+ *
+ * Returns: ID of found name
+ *   < 0 means error
+ */
+PROCPS_EXPORT int procps_ns_get_id(const char *name)
+{
+    int i;
+
+    if (name == NULL)
+        return -EINVAL;
+    for (i=0; i < PROCPS_NS_COUNT; i++)
+        if (!strcmp(ns_names[i], name))
+            return i;
+    return -EINVAL;
+}
+
+/*
+ * procs_ns_read_pid:
+ *
+ * Find all namespaces for the given process.
+ * @pid: Process ID for required process
+ * @nsp: Pointer to the struct procps_ns
+ *
+ * Returns:
+ *   0 on success
+ *   < 0 on error
+ */
+PROCPS_EXPORT int procps_ns_read_pid(
+        const int pid,
+        struct procps_ns *nsp)
+{
+    char path[NSPATHLEN+1];
+    struct stat st;
+    int i;
+
+    if (nsp == NULL)
+        return -EINVAL;
+    if (pid < 1)
+        return -EINVAL;
+
+    for (i=0; i < PROCPS_NS_COUNT; i++) {
+        snprintf(path, NSPATHLEN, "/proc/%d/ns/%s", pid, ns_names[i]);
+        if (0 == stat(path, &st))
+            nsp->ns[i] = (unsigned long)st.st_ino;
+        else
+            nsp->ns[i] = 0;
+    }
+    return 0;
+}