1 files changed, 123 insertions, 0 deletions
diff --git a/lib/fnutil.c b/lib/fnutil.c
new file mode 100644
index 0000000..1ec5ca4
--- /dev/null
+++ b/lib/fnutil.c
@@ -0,0 +1,123 @@
+/* fnutil.c - file name utilities
+   (Originally composed from several files in Lars Wirzenius' publib.)
+
+   Copyright (c) 1994 Lars Wirzenius.  All rights reserved.
+   Copyright (C) 2004 Antti-Juhani Kaijanaho.  All rights reserved.
+
+   Redistribution and use in source and binary forms, with or without
+   modification, are permitted provided that the following conditions
+   are met:
+
+   1. Redistributions of source code must retain the above copyright
+      notice, this list of conditions and the following disclaimer.
+
+   2. Redistributions in binary form must reproduce the above
+      copyright notice, this list of conditions and the following
+      disclaimer in the documentation and/or other materials provided
+      with the distribution.
+
+   THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS
+   OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+   WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+   ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
+   DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+   DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
+   GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+   INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
+   WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+   NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+   SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+ */
+
+#include <assert.h>
+#include <errno.h>
+#include <pwd.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+#ifndef USERNAME_MAX
+#define USERNAME_MAX 9
+#endif
+
+char *fnbase(const char *fname)
+{
+	char *base;
+
+	assert(fname != NULL);
+	base = strrchr(fname, '/');
+	if (base == NULL)
+		return (char *) fname;
+	return base+1;
+}
+
+char * fnqualify(char const * path)
+{
+	size_t len, size;
+	struct passwd *pwd;
+	const char *p;
+
+	assert(path != NULL);
+
+	/* Is it qualified already? */
+	if (path[0] == '/') {
+		return strdup(path);
+	}
+
+	/* Do we just need to prepend the current directory? */
+	if (path[0] != '~') {
+		char * cwd = get_current_dir_name();
+		if (cwd == 0) return 0;
+		len = strlen(cwd);
+		size = len + 1 + strlen(path) + 1; /* +2 for '/' and '\0' */
+		char * res = malloc(size);
+		if (res == 0) {
+			free(cwd);
+			return 0;
+		}
+		sprintf(res, "%s/%s", cwd, path);
+		return res;
+	}
+
+	/* We need to do tilde substitution, get the password entry (which
+           includes the name of the home directory) */
+	if (path[1] == '\0' || path[1] == '/') {
+		pwd = getpwuid(getuid());
+		if (path[1] == '\0')
+			p = path + 1;
+		else
+			p = path + 2;
+	} else {
+
+		p = strchr(path, '/');
+		if (p == NULL)
+			p = strchr(path, '\0');
+		size = (size_t) (p-path);
+		char * username = malloc(size);
+		if (username == 0) {
+			errno = ENOMEM;
+			return 0;
+		}
+		memcpy(username, path+1, size);
+		username[size-1] = '\0';
+
+		pwd = getpwnam(username);
+		if (*p == '/')
+			++p;
+		free(username);
+	}
+	if (pwd == NULL) {
+		errno = ENOENT;
+		return 0;
+	}
+
+
+	/* Now we have all the necessary information, build the result */
+	size = strlen(pwd->pw_dir) + 1 + strlen(p) + 1;
+	char * result = malloc(size);
+	if (result == 0) return 0;
+	sprintf(result, "%s/%s", pwd->pw_dir, p);
+	return result;
+}