whereis: make subdirs scan more robust

* call strchr() only once
* avoid things like strcat(buf, strchr(dir, '*') + 1)
* make it more readable
* improve debug messages

Signed-off-by: Karel Zak <kzak@redhat.com>

diff --git a/misc-utils/whereis.c b/misc-utils/whereis.c
index debd5da55f4904954635f2d623b5b7dcf7d0be40..48361f5981998a1f2913c4434f4ed6242a078c3e 100644 (file)
--- a/misc-utils/whereis.c
+++ b/misc-utils/whereis.c
@@ -263,30 +263,47 @@ static void dirlist_add_subdir(struct wh_dirlist **ls, int type, const char *dir
        char buf[PATH_MAX], *d;
        DIR *dirp;
        struct dirent *dp;
+       char *postfix;
+       size_t len;
 
-       xstrncpy(buf, dir, PATH_MAX);
+       postfix = strchr(dir, '*');
+       if (!postfix)
+               goto ignore;
 
-       d = strchr(buf, '*');
-       if (!d)
-               return;
-       *d = 0;
+       /* copy begin of the path to the buffer (part before '*') */
+       len = (postfix - dir) + 1;
+       xstrncpy(buf, dir, len);
+
+       /* remember place where to append subdirs */
+       d = buf + len - 1;
+
+       /* skip '*' */
+       postfix++;
+       if (!*postfix)
+               postfix = NULL;
 
+       /* open parental dir t scan */
        dirp = opendir(buf);
        if (!dirp)
-               return;
+               goto ignore;
 
-       DBG(LIST, ul_debugobj(*ls, " scanning subdir: %s", dir));
+       DBG(LIST, ul_debugobj(*ls, " scanning subdirs: %s [%s<subdir>%s]",
+                               dir, buf, postfix ? postfix : ""));
 
        while ((dp = readdir(dirp)) != NULL) {
                if (!strcmp(dp->d_name, ".") || !strcmp(dp->d_name, ".."))
                        continue;
-               snprintf(d, PATH_MAX - (d - buf), "%s", dp->d_name);
-               /* a dir definition can have a star in middle of path */
-               strcat(buf, strchr(dir, '*') + 1);
+               if (postfix)
+                       snprintf(d, PATH_MAX - len, "%s%s", dp->d_name, postfix);
+               else
+                       snprintf(d, PATH_MAX - len, "%s", dp->d_name);
+
                dirlist_add_dir(ls, type, buf);
        }
        closedir(dirp);
        return;
+ignore:
+       DBG(LIST, ul_debugobj(*ls, " ignore path: %s", dir));
 }
 
 static void construct_dirlist_from_env(const char *env,