path: follow symbolic link for parent path (2)

[elogind.git] / src / shared / path-util.c

diff --git a/src/shared/path-util.c b/src/shared/path-util.c
index e68d3677a7a1b46fa4f7bfb66791f97f0f3dd028..fae5d20ebb0f6528a2312a33f05d1455c0e85481 100644 (file)
--- a/src/shared/path-util.c
+++ b/src/shared/path-util.c
@@ -129,7 +129,7 @@ char *path_make_absolute_cwd(const char *p) {
         if (!cwd)
                 return NULL;
 
-        return path_make_absolute(p, cwd);
+        return strjoin(cwd, "/", p, NULL);
 }
 
 int path_make_relative(const char *from_dir, const char *to_path, char **_r) {
@@ -306,6 +306,7 @@ char **path_strv_resolve(char **l, const char *prefix) {
                         } else {
                                 /* canonicalized path goes outside of
                                  * prefix, keep the original path instead */
+                                free(u);
                                 u = orig;
                                 orig = NULL;
                         }
@@ -435,6 +436,22 @@ bool path_equal(const char *a, const char *b) {
         }
 }
 
+char* path_join(const char *root, const char *path, const char *rest) {
+        assert(path);
+
+        if (!isempty(root))
+                return strjoin(root, endswith(root, "/") ? "" : "/",
+                               path[0] == '/' ? path+1 : path,
+                               rest ? (endswith(path, "/") ? "" : "/") : NULL,
+                               rest && rest[0] == '/' ? rest+1 : rest,
+                               NULL);
+        else
+                return strjoin(path,
+                               rest ? (endswith(path, "/") ? "" : "/") : NULL,
+                               rest && rest[0] == '/' ? rest+1 : rest,
+                               NULL);
+}
+
 int path_is_mount_point(const char *t, bool allow_symlink) {
 
         union file_handle_union h = {
@@ -472,7 +489,7 @@ int path_is_mount_point(const char *t, bool allow_symlink) {
                 return r;
 
         h.handle.handle_bytes = MAX_HANDLE_SZ;
-        r = name_to_handle_at(AT_FDCWD, parent, &h.handle, &mount_id_parent, 0);
+        r = name_to_handle_at(AT_FDCWD, parent, &h.handle, &mount_id_parent, AT_SYMLINK_FOLLOW);
         if (r < 0) {
                 /* The parent can't do name_to_handle_at() but the
                  * directory we are interested in can? If so, it must
@@ -502,7 +519,7 @@ fallback:
         if (r < 0)
                 return r;
 
-        r = lstat(parent, &b);
+        r = stat(parent, &b);
         if (r < 0)
                 return -errno;
 
@@ -517,7 +534,16 @@ int path_is_read_only_fs(const char *path) {
         if (statvfs(path, &st) < 0)
                 return -errno;
 
-        return !!(st.f_flag & ST_RDONLY);
+        if (st.f_flag & ST_RDONLY)
+                return true;
+
+        /* On NFS, statvfs() might not reflect whether we can actually
+         * write to the remote share. Let's try again with
+         * access(W_OK) which is more reliable, at least sometimes. */
+        if (access(path, W_OK) < 0 && errno == EROFS)
+                return true;
+
+        return false;
 }
 
 int path_is_os_tree(const char *path) {
@@ -538,11 +564,11 @@ int path_is_os_tree(const char *path) {
         return r >= 0;
 }
 
-int find_binary(const char *name, char **filename) {
+int find_binary(const char *name, bool local, char **filename) {
         assert(name);
 
         if (is_path(name)) {
-                if (access(name, X_OK) < 0)
+                if (local && access(name, X_OK) < 0)
                         return -errno;
 
                 if (filename) {
@@ -558,7 +584,7 @@ int find_binary(const char *name, char **filename) {
                 return 0;
         } else {
                 const char *path;
-                char *state, *w;
+                const char *word, *state;
                 size_t l;
 
                 /**
@@ -569,10 +595,10 @@ int find_binary(const char *name, char **filename) {
                 if (!path)
                         path = DEFAULT_PATH;
 
-                FOREACH_WORD_SEPARATOR(w, l, path, ":", state) {
+                FOREACH_WORD_SEPARATOR(word, l, path, ":", state) {
                         _cleanup_free_ char *p = NULL;
 
-                        if (asprintf(&p, "%.*s/%s", (int) l, w, name) < 0)
+                        if (asprintf(&p, "%.*s/%s", (int) l, word, name) < 0)
                                 return -ENOMEM;
 
                         if (access(p, X_OK) < 0)
@@ -632,11 +658,11 @@ int fsck_exists(const char *fstype) {
 
         checker = strappenda("fsck.", fstype);
 
-        r = find_binary(checker, &p);
+        r = find_binary(checker, true, &p);
         if (r < 0)
                 return r;
 
-        /* An fsck that is linked to /bin/true is a non-existant
+        /* An fsck that is linked to /bin/true is a non-existent
          * fsck */
 
         r = readlink_malloc(p, &d);