X-Git-Url: https://www.chiark.greenend.org.uk/ucgi/~mdw/git/disorder/blobdiff_plain/763d5e6ad88ef3ba1cd1d7742d060e4f1e54c6b8..refs/remotes/upstream/issue29:/lib/filepart.c diff --git a/lib/filepart.c b/lib/filepart.c index c385ef2..20889af 100644 --- a/lib/filepart.c +++ b/lib/filepart.c @@ -1,43 +1,132 @@ /* * This file is part of DisOrder - * Copyright (C) 2005 Richard Kettlewell + * Copyright (C) 2005, 2007 Richard Kettlewell * - * 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 of the License, or + * 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. - * + * + * 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 - * USA + * along with this program. If not, see . + */ +/** @file lib/filepart.c + * @brief Filename parsing */ -#include -#include "types.h" - -#include +#include "common.h" #include "filepart.h" #include "mem.h" +/** @brief Parse a filename + * @param path Filename to parse + * @param dirnamep Where to put directory name, or NULL + * @param basenamep Where to put basename, or NULL + */ +static void parse_filename(const char *path, + char **dirnamep, + char **basenamep) { + const char *s, *e = path + strlen(path); + + /* Strip trailing slashes. We never take these into account. */ + while(e > path && e[-1] == '/') + --e; + if(e == path) { + /* The path is empty or contains only slashes */ + if(*path) { + if(dirnamep) + *dirnamep = xstrdup("/"); + if(basenamep) + *basenamep = xstrdup("/"); + } else { + if(dirnamep) + *dirnamep = xstrdup(""); + if(basenamep) + *basenamep = xstrdup(""); + } + } else { + /* The path isn't empty and has more than just slashes. e therefore now + * points at the end of the basename. */ + s = e; + while(s > path && s[-1] != '/') + --s; + /* Now s points at the start of the basename */ + if(basenamep) + *basenamep = xstrndup(s, e - s); + if(s > path) { + --s; + /* s must now be pointing at a '/' before the basename */ + assert(*s == '/'); + while(s > path && s[-1] == '/') + --s; + /* Now s must be pointing at the last '/' after the dirname */ + assert(*s == '/'); + if(s == path) { + /* If we reached the start we must be at the root */ + if(dirnamep) + *dirnamep = xstrdup("/"); + } else { + /* There's more than just the root here */ + if(dirnamep) + *dirnamep = xstrndup(path, s - path); + } + } else { + /* There wasn't a slash */ + if(dirnamep) + *dirnamep = xstrdup("."); + } + } +} + +/** @brief Return the directory part of @p path + * @param path Path to parse + * @return Directory part of @p path + * + * Extracts the directory part of @p path. This is a simple lexical + * transformation and no canonicalization is performed. The result will only + * ever end "/" if it is the root directory. The result will be "." if there + * is no directory part. + */ char *d_dirname(const char *path) { - const char *s; + char *d = 0; - if((s = strrchr(path, '/'))) { - if(s == path) - return xstrdup("/"); - else - return xstrndup(path, s - path); - } else - return xstrdup("."); + parse_filename(path, &d, 0); + assert(d != 0); + return d; } +/** @brief Return the basename part of @p path + * @param path Path to parse + * @return Base part of @p path + * + * Extracts the base part of @p path. This is a simple lexical transformation + * and no canonicalization is performed. The result is always newly allocated + * even if compares equal to @p path. + */ +char *d_basename(const char *path) { + char *b = 0; + + parse_filename(path, 0, &b); + assert(b != 0); + return b; +} + +/** @brief Find the extension part of @p path + * @param path Path to parse + * @return Start of extension in @p path, or NULL + * + * The return value points into @p path and points at the "." at the start of + * the path. If the basename has no extension the result is NULL. Extensions + * are assumed to only contain the ASCII digits and letters. + * + * See also extension(). + */ static const char *find_extension(const char *path) { const char *q = path + strlen(path); @@ -48,12 +137,29 @@ static const char *find_extension(const char *path) { return *q == '.' ? q : 0; } +/** @brief Strip the extension from @p path + * @param path Path to parse + * @return @p path with extension removed, or @p path + * + * The extension is defined exactly as for find_extension(). The result might + * or might not point into @p path. + */ const char *strip_extension(const char *path) { const char *q = find_extension(path); return q ? xstrndup(path, q - path) : path; } +/** @brief Find the extension part of @p path + * @param path Path to parse + * @return Start of extension in @p path, or "" + * + * The return value may points into @p path and if so points at the "." at the + * start of the path. If the basename has no extension the result is "". + * Extensions are assumed to only contain the ASCII digits and letters. + * + * See also find_extension(). + */ const char *extension(const char *path) { const char *q = find_extension(path);