path-util: get rid of prefix_root()

prefix_root() is equivalent to path_join() in almost all ways, hence
let's remove it.

There are subtle differences though: prefix_root() will try shorten
multiple "/" before and after the prefix. path_join() doesn't do that.
This means prefix_root() might return a string shorter than both its
inputs combined, while path_join() never does that. I like the
path_join() semantics better, hence I think dropping prefix_root() is
totally OK. In the end the strings generated by both functon should
always be identical in terms of path_equal() if not streq().

This leaves prefix_roota() in place. Ideally we'd have path_joina(), but
I don't think we can reasonably implement that as a macro. or maybe we
can? (if so, sounds like something for a later PR)

Also add in a few missing OOM checks

1 files changed, 4 insertions, 4 deletions

diff --git a/src/basic/conf-files.c b/src/basic/conf-files.c
index 7c85022f08..a0d17e8a0e 100644
--- a/src/basic/conf-files.c
+++ b/src/basic/conf-files.c
@@ -207,7 +207,7 @@ int conf_files_insert(char ***strv, const char *root, char **dirs, const char *p
                                 _cleanup_free_ char *rdir = NULL;
                                 char *p1, *p2;
 
-                                rdir = prefix_root(root, *dir);
+                                rdir = path_join(root, *dir);
                                 if (!rdir)
                                         return -ENOMEM;
 
@@ -221,7 +221,7 @@ int conf_files_insert(char ***strv, const char *root, char **dirs, const char *p
                                 if (p2) {
                                         /* Our new entry has higher priority */
 
-                                        t = prefix_root(root, path);
+                                        t = path_join(root, path);
                                         if (!t)
                                                 return log_oom();
 
@@ -238,7 +238,7 @@ int conf_files_insert(char ***strv, const char *root, char **dirs, const char *p
         }
 
         /* The new file has lower priority than all the existing entries */
-        t = prefix_root(root, path);
+        t = path_join(root, path);
         if (!t)
                 return -ENOMEM;
 
@@ -313,7 +313,7 @@ int conf_files_list_with_replacement(
                 if (r < 0)
                         return log_error_errno(r, "Failed to extend config file list: %m");
 
-                p = prefix_root(root, replacement);
+                p = path_join(root, replacement);
                 if (!p)
                         return log_oom();
         }