feature/android 9c5e9bb9be6: Correct directory permissions reported for VFS files

[Po Lu]

branch: feature/android
commit 9c5e9bb9be64bedb9aac8b12b4f0c717bcaa4da5
Author: Po Lu <luangruo@yahoo.com>
Commit: Po Lu <luangruo@yahoo.com>

    Correct directory permissions reported for VFS files
    
    * java/org/gnu/emacs/EmacsSafThread.java (statDocument1):
    * src/androidvfs.c (android_afs_stat, android_content_stat)
    (android_saf_root_stat): Report search permissions for files.
---
 java/org/gnu/emacs/EmacsSafThread.java | 59 ++++++++++++++++++----------------
 src/androidvfs.c                       |  7 ++--
 2 files changed, 37 insertions(+), 29 deletions(-)

diff --git a/java/org/gnu/emacs/EmacsSafThread.java 
b/java/org/gnu/emacs/EmacsSafThread.java
index cb69df01bfb..b0d014ffe94 100644
--- a/java/org/gnu/emacs/EmacsSafThread.java
+++ b/java/org/gnu/emacs/EmacsSafThread.java
@@ -97,6 +97,7 @@ public final class EmacsSafThread extends HandlerThread
   /* File access mode constants.  See `man 7 inode'.  */
   public static final int S_IRUSR = 0000400;
   public static final int S_IWUSR = 0000200;
+  public static final int S_IXUSR = 0000100;
   public static final int S_IFCHR = 0020000;
   public static final int S_IFDIR = 0040000;
   public static final int S_IFREG = 0100000;
@@ -1010,7 +1011,8 @@ public final class EmacsSafThread extends HandlerThread
     Uri uriObject;
     String[] projection;
     long[] stat;
-    int index;
+    int flagsIndex, columnIndex, typeIndex;
+    int sizeIndex, mtimeIndex, flags;
     long tem;
     String tem1;
     Cursor cursor;
@@ -1041,7 +1043,16 @@ public final class EmacsSafThread extends HandlerThread
     if (cursor == null)
       return null;
 
-    if (!cursor.moveToFirst ())
+    /* Obtain the indices for columns wanted from this cursor.  */
+    flagsIndex = cursor.getColumnIndex (Document.COLUMN_FLAGS);
+    sizeIndex = cursor.getColumnIndex (Document.COLUMN_SIZE);
+    typeIndex = cursor.getColumnIndex (Document.COLUMN_MIME_TYPE);
+    mtimeIndex = cursor.getColumnIndex (Document.COLUMN_LAST_MODIFIED);
+
+    if (!cursor.moveToFirst ()
+       /* COLUMN_LAST_MODIFIED is allowed to be absent in a
+          conforming documents provider.  */
+       || flagsIndex < 0 || sizeIndex < 0 || typeIndex < 0)
       {
        cursor.close ();
        return null;
@@ -1052,34 +1063,22 @@ public final class EmacsSafThread extends HandlerThread
 
     try
       {
-       index = cursor.getColumnIndex (Document.COLUMN_FLAGS);
-       if (index < 0)
-         return null;
-
-       tem = cursor.getInt (index);
+       flags = cursor.getInt (flagsIndex);
 
        stat[0] |= S_IRUSR;
-       if ((tem & Document.FLAG_SUPPORTS_WRITE) != 0)
+       if ((flags & Document.FLAG_SUPPORTS_WRITE) != 0)
          stat[0] |= S_IWUSR;
 
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.N
-           && (tem & Document.FLAG_VIRTUAL_DOCUMENT) != 0)
+           && (flags & Document.FLAG_VIRTUAL_DOCUMENT) != 0)
          stat[0] |= S_IFCHR;
 
-       index = cursor.getColumnIndex (Document.COLUMN_SIZE);
-       if (index < 0)
-         return null;
-
-       if (cursor.isNull (index))
+       if (cursor.isNull (sizeIndex))
          stat[1] = -1; /* The size is unknown.  */
        else
-         stat[1] = cursor.getLong (index);
+         stat[1] = cursor.getLong (sizeIndex);
 
-       index = cursor.getColumnIndex (Document.COLUMN_MIME_TYPE);
-       if (index < 0)
-         return null;
-
-       tem1 = cursor.getString (index);
+       tem1 = cursor.getString (typeIndex);
 
        /* Check if this is a directory file.  */
        if (tem1.equals (Document.MIME_TYPE_DIR)
@@ -1087,9 +1086,17 @@ public final class EmacsSafThread extends HandlerThread
               time, but Android doesn't forbid document providers
               from returning this information.  */
            && (stat[0] & S_IFCHR) == 0)
-         /* Since FLAG_SUPPORTS_WRITE doesn't apply to directories,
-            just assume they're writable.  */
-         stat[0] |= S_IFDIR | S_IWUSR;
+         {
+           /* Since FLAG_SUPPORTS_WRITE doesn't apply to directories,
+              just assume they're writable.  */
+           stat[0] |= S_IFDIR | S_IWUSR | S_IXUSR;
+
+           /* Directory files cannot be modified if
+              FLAG_DIR_SUPPORTS_CREATE is not set.  */
+
+           if ((flags & Document.FLAG_DIR_SUPPORTS_CREATE) == 0)
+             stat[0] &= ~S_IWUSR;
+         }
 
        /* If this file is neither a character special nor a
           directory, indicate that it's a regular file.  */
@@ -1097,12 +1104,10 @@ public final class EmacsSafThread extends HandlerThread
        if ((stat[0] & (S_IFDIR | S_IFCHR)) == 0)
          stat[0] |= S_IFREG;
 
-       index = cursor.getColumnIndex (Document.COLUMN_LAST_MODIFIED);
-
-       if (index >= 0 && !cursor.isNull (index))
+       if (mtimeIndex >= 0 && !cursor.isNull (mtimeIndex))
          {
            /* Content providers are allowed to not provide mtime.  */
-           tem = cursor.getLong (index);
+           tem = cursor.getLong (mtimeIndex);
            stat[2] = tem;
          }
       }
diff --git a/src/androidvfs.c b/src/androidvfs.c
index bd9112ceb67..c83d3a14b50 100644
--- a/src/androidvfs.c
+++ b/src/androidvfs.c
@@ -2010,6 +2010,9 @@ android_afs_stat (struct android_vnode *vnode, struct 
stat *statb)
       /* Fill in the stat buffer.  */
       statb->st_mode = S_IFDIR | S_IRUSR | S_IRGRP | S_IROTH;
 
+      /* Grant search permissions as well.  */
+      statb->st_mode |= S_IXUSR | S_IXGRP | S_IXOTH;
+
       /* Concoct a nonexistent device and an inode number.  */
       statb->st_dev = -1;
       statb->st_ino = 0;
@@ -2534,7 +2537,7 @@ android_content_stat (struct android_vnode *vnode,
   statb->st_gid = getgid ();
   statb->st_ino = 0;
   statb->st_dev = -2;
-  statb->st_mode = S_IFDIR | S_IRUSR;
+  statb->st_mode = S_IFDIR | S_IRUSR | S_IXUSR;
   return 0;
 }
 
@@ -3418,7 +3421,7 @@ android_saf_root_stat (struct android_vnode *vnode,
   statb->st_gid = getgid ();
   statb->st_ino = 0;
   statb->st_dev = -4;
-  statb->st_mode = S_IFDIR | S_IRUSR;
+  statb->st_mode = S_IFDIR | S_IRUSR | S_IXUSR;
   return 0;
 }