From 1885506f1e01d687b3a206eac7f20a8c49f273ee Mon Sep 17 00:00:00 2001 From: Paul Eggert Date: Thu, 2 Jun 2005 04:59:10 +0000 Subject: Renamed from path-concat.c. (file_name_concat): Renamed from path_concat. All callers changed. [TEST_FILE_NAME_CONCAT]: Renamed from TEST_PATH_CONCAT. --- lib/filenamecat.c | 126 ++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 126 insertions(+) create mode 100644 lib/filenamecat.c (limited to 'lib/filenamecat.c') diff --git a/lib/filenamecat.c b/lib/filenamecat.c new file mode 100644 index 000000000..f56697a6d --- /dev/null +++ b/lib/filenamecat.c @@ -0,0 +1,126 @@ +/* Concatenate two arbitrary file names. + + Copyright (C) 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005 Free + Software Foundation, Inc. + + 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 2, 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, write to the Free Software Foundation, + Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */ + +/* Written by Jim Meyering. */ + +#if HAVE_CONFIG_H +# include +#endif + +/* Specification. */ +#include "filenamecat.h" + +#include + +#include "dirname.h" +#include "xalloc.h" + +#if ! HAVE_MEMPCPY && ! defined mempcpy +# define mempcpy(D, S, N) ((void *) ((char *) memcpy (D, S, N) + (N))) +#endif + +/* Return the longest suffix of F that is a relative file name. + If it has no such suffix, return the empty string. */ + +static char const * +longest_relative_suffix (char const *f) +{ + for (f += FILE_SYSTEM_PREFIX_LEN (f); ISSLASH (*f); f++) + continue; + return f; +} + +/* Concatenate two file name components, DIR and ABASE, in + newly-allocated storage and return the result. + The resulting file name F is such that the commands "ls F" and "(cd + DIR; ls BASE)" refer to the same file, where BASE is ABASE with any + file system prefixes and leading separators removed. + Arrange for a directory separator if necessary between DIR and BASE + in the result, removing any redundant separators. + In any case, if BASE_IN_RESULT is non-NULL, set + *BASE_IN_RESULT to point to the copy of ABASE in the returned + concatenation. However, if ABASE begins with more than one slash, + set *BASE_IN_RESULT to point to the sole corresponding slash that + is copied into the result buffer. + + Report an error if memory is exhausted. */ + +char * +file_name_concat (char const *dir, char const *abase, char **base_in_result) +{ + char const *dirbase = base_name (dir); + size_t dirbaselen = base_len (dirbase); + size_t dirlen = dirbase - dir + dirbaselen; + size_t needs_separator = (dirbaselen && ! ISSLASH (dirbase[dirbaselen - 1])); + + char const *base = longest_relative_suffix (abase); + size_t baselen = strlen (base); + + char *p_concat = xmalloc (dirlen + needs_separator + baselen + 1); + char *p; + + p = mempcpy (p_concat, dir, dirlen); + *p = DIRECTORY_SEPARATOR; + p += needs_separator; + + if (base_in_result) + *base_in_result = p - IS_ABSOLUTE_FILE_NAME (abase); + + p = mempcpy (p, base, baselen); + *p = '\0'; + + return p_concat; +} + +#ifdef TEST_FILE_NAME_CONCAT +# include +# include +int +main () +{ + static char const *const tests[][3] = + { + {"a", "b", "a/b"}, + {"a/", "b", "a/b"}, + {"a/", "/b", "a/b"}, + {"a", "/b", "a/b"}, + + {"/", "b", "/b"}, + {"/", "/b", "/b"}, + {"/", "/", "/"}, + {"a", "/", "a/"}, /* this might deserve a diagnostic */ + {"/a", "/", "/a/"}, /* this might deserve a diagnostic */ + {"a", "//b", "a/b"}, + }; + size_t i; + bool fail = false; + for (i = 0; i < sizeof tests / sizeof tests[0]; i++) + { + char *base_in_result; + char const *const *t = tests[i]; + char *res = file_name_concat (t[0], t[1], &base_in_result); + if (strcmp (res, t[2]) != 0) + { + printf ("got %s, expected %s\n", res, t[2]); + fail = true; + } + } + exit (fail ? EXIT_FAILURE : EXIT_SUCCESS); +} +#endif -- cgit v1.2.3-54-g00ecf