1 /* Program name management. 2 Copyright (C) 2001-2003, 2005-2021 Free Software Foundation, Inc. 3 Written by Bruno Haible <bruno@clisp.org>, 2001. 4 5 This program is free software: you can redistribute it and/or modify 6 it under the terms of the GNU General Public License as published by 7 the Free Software Foundation; either version 3 of the License, or 8 (at your option) any later version. 9 10 This program is distributed in the hope that it will be useful, 11 but WITHOUT ANY WARRANTY; without even the implied warranty of 12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 13 GNU General Public License for more details. 14 15 You should have received a copy of the GNU General Public License 16 along with this program. If not, see <https://www.gnu.org/licenses/>. */ 17 18 19 #include <config.h> 20 21 /* Specification. */ 22 #undef ENABLE_RELOCATABLE /* avoid defining set_program_name as a macro */ 23 #include "progname.h" 24 25 #include <errno.h> /* get program_invocation_name declaration */ 26 #include <stdio.h> 27 #include <stdlib.h> 28 #include <string.h> 29 30 31 /* String containing name the program is called with. 32 To be initialized by main(). */ 33 const char *program_name = NULL; 34 35 /* Set program_name, based on argv[0]. 36 argv0 must be a string allocated with indefinite extent, and must not be 37 modified after this call. */ 38 void 39 set_program_name (const char *argv0) /* */ 40 { 41 /* libtool creates a temporary executable whose name is sometimes prefixed 42 with "lt-" (depends on the platform). It also makes argv[0] absolute. 43 But the name of the temporary executable is a detail that should not be 44 visible to the end user and to the test suite. 45 Remove this "<dirname>/.libs/" or "<dirname>/.libs/lt-" prefix here. */ 46 const char *slash; 47 const char *base; 48 49 /* Sanity check. POSIX requires the invoking process to pass a non-NULL 50 argv[0]. */ 51 if (argv0 == NULL) 52 { 53 /* It's a bug in the invoking program. Help diagnosing it. */ 54 fputs ("A NULL argv[0] was passed through an exec system call.\n", 55 stderr); 56 abort (); 57 } 58 59 slash = strrchr (argv0, '/'); 60 base = (slash != NULL ? slash + 1 : argv0); 61 if (base - argv0 >= 7 && strncmp (base - 7, "/.libs/", 7) == 0) 62 { 63 argv0 = base; 64 if (strncmp (base, "lt-", 3) == 0) 65 { 66 argv0 = base + 3; 67 /* On glibc systems, remove the "lt-" prefix from the variable 68 program_invocation_short_name. */ 69 #if HAVE_DECL_PROGRAM_INVOCATION_SHORT_NAME 70 program_invocation_short_name = (char *) argv0; 71 #endif 72 } 73 } 74 75 /* But don't strip off a leading <dirname>/ in general, because when the user 76 runs 77 /some/hidden/place/bin/cp foo foo 78 he should get the error message 79 /some/hidden/place/bin/cp: `foo' and `foo' are the same file 80 not 81 cp: `foo' and `foo' are the same file 82 */ 83 84 program_name = argv0; 85 86 /* On glibc systems, the error() function comes from libc and uses the 87 variable program_invocation_name, not program_name. So set this variable 88 as well. */ 89 #if HAVE_DECL_PROGRAM_INVOCATION_NAME 90 program_invocation_name = (char *) argv0; 91 #endif 92 }