1 files changed, 92 insertions, 0 deletions
diff --git a/lib/progname.c b/lib/progname.c
new file mode 100644
index 0000000..ed928e0
--- /dev/null
+++ b/lib/progname.c
@@ -0,0 +1,92 @@
+/* Program name management.
+   Copyright (C) 2001-2003, 2005-2023 Free Software Foundation, Inc.
+   Written by Bruno Haible <bruno@clisp.org>, 2001.
+
+   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 3 of the License, 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, see <https://www.gnu.org/licenses/>.  */
+
+
+#include <config.h>
+
+/* Specification.  */
+#undef ENABLE_RELOCATABLE /* avoid defining set_program_name as a macro */
+#include "progname.h"
+
+#include <errno.h> /* get program_invocation_name declaration */
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+
+/* String containing name the program is called with.
+   To be initialized by main().  */
+const char *program_name = NULL;
+
+/* Set program_name, based on argv[0].
+   argv0 must be a string allocated with indefinite extent, and must not be
+   modified after this call.  */
+void
+set_program_name (const char *argv0)
+{
+  /* libtool creates a temporary executable whose name is sometimes prefixed
+     with "lt-" (depends on the platform).  It also makes argv[0] absolute.
+     But the name of the temporary executable is a detail that should not be
+     visible to the end user and to the test suite.
+     Remove this "<dirname>/.libs/" or "<dirname>/.libs/lt-" prefix here.  */
+  const char *slash;
+  const char *base;
+
+  /* Sanity check.  POSIX requires the invoking process to pass a non-NULL
+     argv[0].  */
+  if (argv0 == NULL)
+    {
+      /* It's a bug in the invoking program.  Help diagnosing it.  */
+      fputs ("A NULL argv[0] was passed through an exec system call.\n",
+             stderr);
+      abort ();
+    }
+
+  slash = strrchr (argv0, '/');
+  base = (slash != NULL ? slash + 1 : argv0);
+  if (base - argv0 >= 7 && strncmp (base - 7, "/.libs/", 7) == 0)
+    {
+      argv0 = base;
+      if (strncmp (base, "lt-", 3) == 0)
+        {
+          argv0 = base + 3;
+          /* On glibc systems, remove the "lt-" prefix from the variable
+             program_invocation_short_name.  */
+#if HAVE_DECL_PROGRAM_INVOCATION_SHORT_NAME
+          program_invocation_short_name = (char *) argv0;
+#endif
+        }
+    }
+
+  /* But don't strip off a leading <dirname>/ in general, because when the user
+     runs
+         /some/hidden/place/bin/cp foo foo
+     he should get the error message
+         /some/hidden/place/bin/cp: `foo' and `foo' are the same file
+     not
+         cp: `foo' and `foo' are the same file
+   */
+
+  program_name = argv0;
+
+  /* On glibc systems, the error() function comes from libc and uses the
+     variable program_invocation_name, not program_name.  So set this variable
+     as well.  */
+#if HAVE_DECL_PROGRAM_INVOCATION_NAME
+  program_invocation_name = (char *) argv0;
+#endif
+}