Split common utility functions for libalpm and pacman

There is duplicated code in the util.c files in the libalpm and pacman
source code. Split this into a separate file so that it can be shared
via a symlink. This prevents code divergence between the two code bases.

Also, move mbasename and mdirname from pacman/util.c into util-common.c
in preparation for the following patch that uses them to add an extension
to pacsave files.

Signed-off-by: Allan McRae <allan@archlinux.org>

3 files changed, 145 insertions, 0 deletions

diff --git a/src/common/Makefile.am b/src/common/Makefile.am
new file mode 100644
index 00000000..49503333
--- /dev/null
+++ b/src/common/Makefile.am
@@ -0,0 +1,4 @@
+EXTRA_DIST = \
+	util-common.h util-common.c
+
+# vim:set ts=2 sw=2 noet:
diff --git a/src/common/util-common.c b/src/common/util-common.c
new file mode 100644
index 00000000..e2b5939c
--- /dev/null
+++ b/src/common/util-common.c
@@ -0,0 +1,109 @@
+/*
+ *  util-common.c
+ *
+ *  Copyright (c) 2006-2012 Pacman Development Team <pacman-dev@archlinux.org>
+ *
+ *  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
+ *  (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.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <stdlib.h>
+#include <string.h>
+
+#include "util-common.h"
+
+
+/** Parse the basename of a program from a path.
+* @param path path to parse basename from
+*
+* @return everything following the final '/'
+*/
+const char *mbasename(const char *path)
+{
+	const char *last = strrchr(path, '/');
+	if(last) {
+		return last + 1;
+	}
+	return path;
+}
+
+/** Parse the dirname of a program from a path.
+* The path returned should be freed.
+* @param path path to parse dirname from
+*
+* @return everything preceding the final '/'
+*/
+char *mdirname(const char *path)
+{
+	char *ret, *last;
+
+	/* null or empty path */
+	if(path == NULL || path == '\0') {
+		return strdup(".");
+	}
+
+	if((ret = strdup(path)) == NULL) {
+		return NULL;
+	}
+
+	last = strrchr(ret, '/');
+
+	if(last != NULL) {
+		/* we found a '/', so terminate our string */
+		if(last == ret) {
+			/* return "/" for root */
+			last++;
+		}
+		*last = '\0';
+		return ret;
+	}
+
+	/* no slash found */
+	free(ret);
+	return strdup(".");
+}
+
+#ifndef HAVE_STRNDUP
+/* A quick and dirty implementation derived from glibc */
+/** Determines the length of a fixed-size string.
+ * @param s string to be measured
+ * @param max maximum number of characters to search for the string end
+ * @return length of s or max, whichever is smaller
+ */
+static size_t strnlen(const char *s, size_t max)
+{
+    register const char *p;
+    for(p = s; *p && max--; ++p);
+    return (p - s);
+}
+
+/** Copies a string.
+ * Returned string needs to be freed
+ * @param s string to be copied
+ * @param n maximum number of characters to copy
+ * @return pointer to the new string on success, NULL on error
+ */
+char *strndup(const char *s, size_t n)
+{
+  size_t len = strnlen(s, n);
+  char *new = (char *) malloc(len + 1);
+
+  if(new == NULL)
+    return NULL;
+
+  new[len] = '\0';
+  return (char *)memcpy(new, s, len);
+}
+#endif
+
+/* vim: set ts=2 sw=2 noet: */
diff --git a/src/common/util-common.h b/src/common/util-common.h
new file mode 100644
index 00000000..04d4e9d8
--- /dev/null
+++ b/src/common/util-common.h
@@ -0,0 +1,32 @@
+/*
+ *  util-common.h
+ *
+ *  Copyright (c) 2006-2013 Pacman Development Team <pacman-dev@archlinux.org>
+ *
+ *  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
+ *  (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.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef _PM_UTIL_COMMON_H
+#define _PM_UTIL_COMMON_H
+
+const char *mbasename(const char *path);
+char *mdirname(const char *path);
+
+#ifndef HAVE_STRNDUP
+char *strndup(const char *s, size_t n);
+#endif
+
+#endif /* _PM_UTIL_COMMON_H */
+
+/* vim: set ts=2 sw=2 noet: */