| 1 | /* Concatenate two arbitrary file names.
|
|---|
| 2 |
|
|---|
| 3 | Copyright (C) 1996-2007, 2009-2012 Free Software Foundation, Inc.
|
|---|
| 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 <http://www.gnu.org/licenses/>. */
|
|---|
| 17 |
|
|---|
| 18 | /* Written by Jim Meyering. */
|
|---|
| 19 |
|
|---|
| 20 | #include <config.h>
|
|---|
| 21 |
|
|---|
| 22 | /* Specification. */
|
|---|
| 23 | #include "filenamecat.h"
|
|---|
| 24 |
|
|---|
| 25 | #include <stdlib.h>
|
|---|
| 26 | #include <string.h>
|
|---|
| 27 |
|
|---|
| 28 | #include "dirname.h"
|
|---|
| 29 |
|
|---|
| 30 | #if ! HAVE_MEMPCPY && ! defined mempcpy
|
|---|
| 31 | # define mempcpy(D, S, N) ((void *) ((char *) memcpy (D, S, N) + (N)))
|
|---|
| 32 | #endif
|
|---|
| 33 |
|
|---|
| 34 | /* Return the longest suffix of F that is a relative file name.
|
|---|
| 35 | If it has no such suffix, return the empty string. */
|
|---|
| 36 |
|
|---|
| 37 | static char const * _GL_ATTRIBUTE_PURE
|
|---|
| 38 | longest_relative_suffix (char const *f)
|
|---|
| 39 | {
|
|---|
| 40 | for (f += FILE_SYSTEM_PREFIX_LEN (f); ISSLASH (*f); f++)
|
|---|
| 41 | continue;
|
|---|
| 42 | return f;
|
|---|
| 43 | }
|
|---|
| 44 |
|
|---|
| 45 | /* Concatenate two file name components, DIR and ABASE, in
|
|---|
| 46 | newly-allocated storage and return the result.
|
|---|
| 47 | The resulting file name F is such that the commands "ls F" and "(cd
|
|---|
| 48 | DIR; ls BASE)" refer to the same file, where BASE is ABASE with any
|
|---|
| 49 | file system prefixes and leading separators removed.
|
|---|
| 50 | Arrange for a directory separator if necessary between DIR and BASE
|
|---|
| 51 | in the result, removing any redundant separators.
|
|---|
| 52 | In any case, if BASE_IN_RESULT is non-NULL, set
|
|---|
| 53 | *BASE_IN_RESULT to point to the copy of ABASE in the returned
|
|---|
| 54 | concatenation. However, if ABASE begins with more than one slash,
|
|---|
| 55 | set *BASE_IN_RESULT to point to the sole corresponding slash that
|
|---|
| 56 | is copied into the result buffer.
|
|---|
| 57 |
|
|---|
| 58 | Return NULL if malloc fails. */
|
|---|
| 59 |
|
|---|
| 60 | char *
|
|---|
| 61 | mfile_name_concat (char const *dir, char const *abase, char **base_in_result)
|
|---|
| 62 | {
|
|---|
| 63 | char const *dirbase = last_component (dir);
|
|---|
| 64 | size_t dirbaselen = base_len (dirbase);
|
|---|
| 65 | size_t dirlen = dirbase - dir + dirbaselen;
|
|---|
| 66 | size_t needs_separator = (dirbaselen && ! ISSLASH (dirbase[dirbaselen - 1]));
|
|---|
| 67 |
|
|---|
| 68 | char const *base = longest_relative_suffix (abase);
|
|---|
| 69 | size_t baselen = strlen (base);
|
|---|
| 70 |
|
|---|
| 71 | char *p_concat = malloc (dirlen + needs_separator + baselen + 1);
|
|---|
| 72 | char *p;
|
|---|
| 73 |
|
|---|
| 74 | if (p_concat == NULL)
|
|---|
| 75 | return NULL;
|
|---|
| 76 |
|
|---|
| 77 | p = mempcpy (p_concat, dir, dirlen);
|
|---|
| 78 | *p = DIRECTORY_SEPARATOR;
|
|---|
| 79 | p += needs_separator;
|
|---|
| 80 |
|
|---|
| 81 | if (base_in_result)
|
|---|
| 82 | *base_in_result = p - IS_ABSOLUTE_FILE_NAME (abase);
|
|---|
| 83 |
|
|---|
| 84 | p = mempcpy (p, base, baselen);
|
|---|
| 85 | *p = '\0';
|
|---|
| 86 |
|
|---|
| 87 | return p_concat;
|
|---|
| 88 | }
|
|---|