X-Git-Url: http://erislabs.net/gitweb/?a=blobdiff_plain;f=lib%2Fbasename.c;h=426ed40f1a9e19f37abb6be20f72d587a2fc9b8a;hb=2f2f93bfb6e0991467a287c1f4a3e0c13b227ef1;hp=b6de3d610ec7b73a7f9199fe5fd2680c91dae5f7;hpb=267a39bafd249d7eb9c37df06dc6defcf41cb343;p=gnulib.git diff --git a/lib/basename.c b/lib/basename.c index b6de3d610..426ed40f1 100644 --- a/lib/basename.c +++ b/lib/basename.c @@ -1,12 +1,12 @@ -/* basename.c -- return the last element in a path +/* basename.c -- return the last element in a file name - Copyright (C) 1990, 1998, 1999, 2000, 2001, 2003, 2004 Free + Copyright (C) 1990, 1998, 1999, 2000, 2001, 2003, 2004, 2005, 2006 Free Software Foundation, Inc. - This program is free software; you can redistribute it and/or modify + 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. + 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 @@ -14,66 +14,115 @@ 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. */ + along with this program. If not, see . */ -#if HAVE_CONFIG_H -# include -#endif +#include #include "dirname.h" -#include -/* In general, we can't use the builtin `basename' function if available, - since it has different meanings in different environments. - In some environments the builtin `basename' modifies its argument. +#include +#include "xalloc.h" +#include "xstrndup.h" - Return the address of the last file name component of NAME. If - NAME has no file name components because it is all slashes, return - NAME if it is empty, the address of its last slash otherwise. */ +/* Return the address of the last file name component of NAME. If + NAME has no relative file name components because it is a file + system root, return the empty string. */ char * -base_name (char const *name) +last_component (char const *name) { char const *base = name + FILE_SYSTEM_PREFIX_LEN (name); char const *p; + bool saw_slash = false; + + while (ISSLASH (*base)) + base++; for (p = base; *p; p++) { if (ISSLASH (*p)) + saw_slash = true; + else if (saw_slash) { - /* Treat multiple adjacent slashes like a single slash. */ - do p++; - while (ISSLASH (*p)); - - /* If the file name ends in slash, use the trailing slash as - the basename if no non-slashes have been found. */ - if (! *p) - { - if (ISSLASH (*base)) - base = p - 1; - break; - } - - /* *P is a non-slash preceded by a slash. */ base = p; + saw_slash = false; } } return (char *) base; } -/* Return the length of of the basename NAME. Typically NAME is the - value returned by base_name. Act like strlen (NAME), except omit - redundant trailing slashes. */ + +/* In general, we can't use the builtin `basename' function if available, + since it has different meanings in different environments. + In some environments the builtin `basename' modifies its argument. + + Return the last file name component of NAME, allocated with + xmalloc. On systems with drive letters, a leading "./" + distinguishes relative names that would otherwise look like a drive + letter. Unlike POSIX basename(), NAME cannot be NULL, + base_name("") returns "", and the first trailing slash is not + stripped. + + If lstat (NAME) would succeed, then { chdir (dir_name (NAME)); + lstat (base_name (NAME)); } will access the same file. Likewise, + if the sequence { chdir (dir_name (NAME)); + rename (base_name (NAME), "foo"); } succeeds, you have renamed NAME + to "foo" in the same directory NAME was in. */ + +char * +base_name (char const *name) +{ + char const *base = last_component (name); + size_t length; + + /* If there is no last component, then name is a file system root or the + empty string. */ + if (! *base) + return xstrndup (name, base_len (name)); + + /* Collapse a sequence of trailing slashes into one. */ + length = base_len (base); + if (ISSLASH (base[length])) + length++; + + /* On systems with drive letters, `a/b:c' must return `./b:c' rather + than `b:c' to avoid confusion with a drive letter. On systems + with pure POSIX semantics, this is not an issue. */ + if (FILE_SYSTEM_PREFIX_LEN (base)) + { + char *p = xmalloc (length + 3); + p[0] = '.'; + p[1] = '/'; + memcpy (p + 2, base, length); + p[length + 2] = '\0'; + return p; + } + + /* Finally, copy the basename. */ + return xstrndup (base, length); +} + +/* Return the length of the basename NAME. Typically NAME is the + value returned by base_name or last_component. Act like strlen + (NAME), except omit all trailing slashes. */ size_t base_len (char const *name) { size_t len; + size_t prefix_len = FILE_SYSTEM_PREFIX_LEN (name); for (len = strlen (name); 1 < len && ISSLASH (name[len - 1]); len--) continue; + if (DOUBLE_SLASH_IS_DISTINCT_ROOT && len == 1 + && ISSLASH (name[0]) && ISSLASH (name[1]) && ! name[2]) + return 2; + + if (FILE_SYSTEM_DRIVE_PREFIX_CAN_BE_RELATIVE && prefix_len + && len == prefix_len && ISSLASH (name[prefix_len])) + return prefix_len + 1; + return len; }