Initial packer/vagrant/autotest setup

[grml-debootstrap.git] / packer / fake-uname.c

diff --git a/packer/fake-uname.c b/packer/fake-uname.c
new file mode 100644 (file)
index 0000000..7bbcb24
--- /dev/null
+++ b/packer/fake-uname.c
@@ -0,0 +1,44 @@
+#include <stdio.h>
+#include <string.h>
+#include <dlfcn.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <sys/syslog.h>
+#include <sys/utsname.h>
+
+#ifndef UTS_RELEASE
+#define UTS_RELEASE "0.0.0"
+#endif
+
+#ifndef RTLD_NEXT
+#define RTLD_NEXT      ((void *) -1l)
+#endif
+
+typedef int (*uname_t) (struct utsname * buf);
+
+static void *get_libc_func(const char *funcname)
+{
+  void *func;
+  char *error;
+
+  func = dlsym(RTLD_NEXT, funcname);
+  if ((error = dlerror()) != NULL) {
+    fprintf(stderr, "Can't locate libc function `%s' error: %s", funcname, error);
+    _exit(EXIT_FAILURE);
+  }
+  return func;
+}
+
+int uname(struct utsname *buf)
+{
+  int ret;
+  char *env = NULL;
+  uname_t real_uname = (uname_t) get_libc_func("uname");
+
+  ret = real_uname((struct utsname *) buf);
+  strncpy(buf->release, ((env = getenv("UTS_RELEASE")) == NULL) ? UTS_RELEASE : env, 65);
+  return ret;
+}