/* path-concat.c -- concatenate two arbitrary pathnames
- Copyright (C) 1996, 1997 Free Software Foundation, Inc.
+
+ Copyright (C) 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004 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
/* Written by Jim Meyering. */
-#ifdef HAVE_CONFIG_H
+#if HAVE_CONFIG_H
# include <config.h>
#endif
+/* Specification. */
+#include "path-concat.h"
+
#ifndef HAVE_MEMPCPY
# define mempcpy(D, S, N) ((void *) ((char *) memcpy (D, S, N) + (N)))
#endif
#include <stdio.h>
-#ifdef HAVE_STRING_H
-# include <string.h>
+#include <stdlib.h>
+#include <string.h>
+
+#if HAVE_UNISTD_H
+# include <unistd.h>
#endif
-#include <sys/types.h>
-char *malloc ();
+#include "strdup.h"
+#include "dirname.h"
+#include "xalloc.h"
-/* Concatenate two pathname components, DIR and BASE, in newly-allocated
- storage and return the result. Return 0 if out of memory. Add a slash
- between DIR and BASE in the result if neither would contribute one.
- If each would contribute at least one, elide one from the end of DIR.
- Otherwise, simply concatenate DIR and BASE. In any case, if
- BASE_IN_RESULT is non-NULL, set *BASE_IN_RESULT to point to the copy of
- BASE in the returned concatenation. */
+/* Concatenate two pathname components, DIR and BASE, in
+ newly-allocated storage and return the result. Return 0 if out of
+ memory. Add a slash between DIR and BASE in the result if neither
+ would contribute one. If each would contribute at least one, elide
+ one from the end of DIR. Otherwise, simply concatenate DIR and
+ BASE. In any case, if BASE_IN_RESULT is non-NULL, set
+ *BASE_IN_RESULT to point to the copy of BASE in the returned
+ concatenation.
+
+ DIR may be NULL, BASE must not be.
+
+ Return NULL if memory is exhausted. */
char *
-path_concat (dir, base, base_in_result)
- const char *dir;
- const char *base;
- char **base_in_result;
+path_concat (const char *dir, const char *base, char **base_in_result)
{
char *p;
char *p_concat;
- size_t base_len = strlen (base);
- size_t dir_len = strlen (dir);
-
- p_concat = malloc (dir_len + base_len + 2);
+ size_t baselen;
+ size_t dirlen;
+
+ if (!dir)
+ {
+ p_concat = strdup (base);
+ if (base_in_result)
+ *base_in_result = p_concat;
+ return p_concat;
+ }
+
+ /* DIR is not empty. */
+ baselen = base_len (base);
+ dirlen = strlen (dir);
+
+ p_concat = malloc (dirlen + baselen + 2);
if (!p_concat)
return 0;
- p = mempcpy (p_concat, dir, dir_len);
+ p = mempcpy (p_concat, dir, dirlen);
- if (*(p - 1) == '/' && *base == '/')
- --p;
- else if (*(p - 1) != '/' && *base != '/')
- *p++ = '/';
+ if (FILESYSTEM_PREFIX_LEN (dir) < dirlen)
+ {
+ if (ISSLASH (*(p - 1)) && ISSLASH (*base))
+ --p;
+ else if (!ISSLASH (*(p - 1)) && !ISSLASH (*base))
+ *p++ = DIRECTORY_SEPARATOR;
+ }
if (base_in_result)
*base_in_result = p;
- memcpy (p, base, base_len + 1);
+ memcpy (p, base, baselen);
+ p[baselen] = '\0';
return p_concat;
}
+
+/* Same, but die when memory is exhausted. */
+
+char *
+xpath_concat (const char *dir, const char *base, char **base_in_result)
+{
+ char *res = path_concat (dir, base, base_in_result);
+ if (! res)
+ xalloc_die ();
+ return res;
+}