diff options
Diffstat (limited to 'gnu/progname.c')
-rw-r--r-- | gnu/progname.c | 92 |
1 files changed, 92 insertions, 0 deletions
diff --git a/gnu/progname.c b/gnu/progname.c new file mode 100644 index 0000000..fe93bca --- /dev/null +++ b/gnu/progname.c @@ -0,0 +1,92 @@ +/* Program name management. + Copyright (C) 2001-2003, 2005-2015 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 <http://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 +} |