1 files changed, 96 insertions, 1 deletions

diff --git a/lib/util.c b/lib/util.c
index 6cfcf1f..29423d1 100644
--- a/lib/util.c
+++ b/lib/util.c
@@ -5,10 +5,54 @@
 #include <sys/stat.h>
 #include <errno.h>
 #include <string.h>
+#include <stdlib.h>
+#include <unistd.h>
+
+int vl_mkdir_parents_open(int fd, char *path, mode_t nmode)
+{
+  int last = 0;
+  int at = fd;
+  int temp;
+  char *ch = path;
+  char *compstart = path;
+  int ret = -1;
+
+  do {
+    if (*ch == '/' || (*ch == '\0' && (last = 1))) {
+      if (ch == path) continue; /* false alarm: we're trying to create / */
+
+      *ch = '\0';
+
+      if (mkdirat(at, compstart, nmode) < 0 && errno != EEXIST) {
+        vl_debug("%s: failed to create directory %s: %s", __func__, path, strerror(errno));
+        goto cleanup;
+      }
+
+      temp = openat(at, compstart, O_RDONLY);
+      if (temp < 0) {
+        vl_debug("%s: failed to open new directory %s: %s", __func__, path, strerror(errno));
+        goto cleanup;
+      }
+
+      close(at);
+      temp = at;
+
+      compstart = ch + 1;
+      if (!last) *ch = '/'; /* make an effort to unclobber path */
+    }
+  } while (*(ch++));
+
+  ret = 0;
+
+cleanup:
+  if (at != fd) close(at);
+  return ret;
+}
 
 /* will clobber path */
-int vl_mkdir_parents(int fd, char *path, mode_t mode)
+int vl_mkdir_parents(int fd, char *path, mode_t nmode)
 {
+#if 0
   int last = 0;
 
   char *ch = path;
@@ -25,6 +69,57 @@ int vl_mkdir_parents(int fd, char *path, mode_t mode)
       if (!last) *ch = '/';
     }
   } while (*(ch++));
+#endif /* old implementation */
+
+  fd = vl_mkdir_parents_open(fd, path, nmode);
+  if (fd >= 0) {
+    close(fd);
+    return 0;
+  }
+
+  return -1;
+}
+
+/* def: home-relative default */
+/* https://specifications.freedesktop.org/basedir/latest/ */
+static int open_xdg_dir(vl_arena *scratch, const char *xdg_env, const char *def)
+{
+  const char *xdg_dir = getenv(xdg_env);
+  int dfd;
+
+  if (xdg_dir && *xdg_dir == '/') {
+    char *xdg_dir_mod = vl_arena_strdup(scratch, xdg_dir);
+
+    /* must be an absolute path */
+    if ((dfd = vl_mkdir_parents_open(AT_FDCWD, xdg_dir_mod, 0700)) < 0) {
+      vl_warn("get_xdg_dir: Failed to create %s: %s", xdg_dir, strerror(errno));
+      return -1;
+    }
+
+    return dfd;
+  }
+
+  /* xdg dir is missing or not absolute (as required) */
+  const char *home = getenv("HOME");
+  /* TODO: could get passwd entry for home directory */
+
+  if (!home || *home != '/') {
+    vl_warn("Missing $HOME (or it is not an absolute path)! Cannot decide launcher data directory.");
+    return -1;
+  }
+
+  char *path = vl_arena_sprintf(scratch, "%s/%s", home, def);
+
+  if ((dfd = vl_mkdir_parents_open(AT_FDCWD, path, 0700)) < 0) {
+    vl_warn("%s: failed to create/open xdg dir %s: %s", __func__, path, strerror(errno));
+    return -1;
+  }
 
   return 0;
 }
+
+int vl_get_data_dir(vl_arena *alloc, const char *application, char **opath)
+{
+  /* TODO: not just linux */
+  int datadir = open_xdg_dir(alloc, "XDG_DATA_HOME", ".local/share");
+}