Prevent passwords from being recorded during text conversion

* doc/lispref/commands.texi (Misc Events): Document new value of
text-conversion-style.

* java/org/gnu/emacs/EmacsService.java (EmacsService)
<IC_MODE_PASSWORD>: New constant.

* java/org/gnu/emacs/EmacsView.java (onCreateInputConnection):
Set TYPE_TEXT_VARIATION_PASSWORD and IME_FLAG_FORCE_ASII if mode
is IC_MODE_PASSWORD.

* lisp/subr.el (read-passwd): Set text-conversion-style to
`password'.

* src/androidgui.h (enum android_ic_mode): New value
ANDROID_IC_MODE_PASSWORD.

* src/androidterm.c (android_reset_conversion): Handle
`password'.

* src/buffer.c (syms_of_buffer)
<&BVAR (current_buffer, text_conversion_style)>: Update doc
string.

* src/textconv.c (syms_of_textconv) <Qpassword>: New DEFSYM.
<Vtext_conversion_edits>: Fix typos in doc string.

4 files changed, 15 insertions, 4 deletions

diff --git a/src/androidgui.h b/src/androidgui.h
index d89aee51055..f941c7cc577 100644
--- a/src/androidgui.h
+++ b/src/androidgui.h
@@ -618,9 +618,10 @@ enum android_lookup_status
 
 enum android_ic_mode
   {
-    ANDROID_IC_MODE_NULL   = 0,
-    ANDROID_IC_MODE_ACTION = 1,
-    ANDROID_IC_MODE_TEXT   = 2,
+    ANDROID_IC_MODE_NULL     = 0,
+    ANDROID_IC_MODE_ACTION   = 1,
+    ANDROID_IC_MODE_TEXT     = 2,
+    ANDROID_IC_MODE_PASSWORD = 3,
   };
 
 enum android_stack_mode
diff --git a/src/androidterm.c b/src/androidterm.c
index ba9b6d3b8a9..c920375fdbe 100644
--- a/src/androidterm.c
+++ b/src/androidterm.c
@@ -6276,6 +6276,8 @@ android_reset_conversion (struct frame *f)
 
   if (NILP (style) || conversion_disabled_p ())
     mode = ANDROID_IC_MODE_NULL;
+  else if (EQ (style, Qpassword))
+    mode = ANDROID_IC_MODE_PASSWORD;
   else if (EQ (style, Qaction) || EQ (f->selected_window,
                                       f->minibuffer_window))
     mode = ANDROID_IC_MODE_ACTION;
diff --git a/src/buffer.c b/src/buffer.c
index 07d19dfc078..9f954e1aba9 100644
--- a/src/buffer.c
+++ b/src/buffer.c
@@ -5900,12 +5900,19 @@ Use Custom to set this variable and update the display.  */);
                                                      text_conversion_style),
                      Qnil,
     doc: /* How the on screen keyboard's input method should insert in this buffer.
+
 When nil, the input method will be disabled and an ordinary keyboard
 will be displayed in its place.
+
 When the symbol `action', the input method will insert text directly, but
 will send `return' key events instead of inserting new line characters.
 Any other value means that the input method will insert text directly.
 
+When the symbol `password', an input method capable of ASCII input will
+be enabled, and will not save entered text where it will be retrieved
+for text suggestions or other features not suited to handling sensitive
+information, in addition to reporting `return' as when `action'.
+
 If you need to make non-buffer local changes to this variable, use
 `overriding-text-conversion-style', which see.
 
diff --git a/src/textconv.c b/src/textconv.c
index 0941848dd09..9625c884e16 100644
--- a/src/textconv.c
+++ b/src/textconv.c
@@ -2318,6 +2318,7 @@ void
 syms_of_textconv (void)
 {
   DEFSYM (Qaction, "action");
+  DEFSYM (Qpassword, "password");
   DEFSYM (Qtext_conversion, "text-conversion");
   DEFSYM (Qpush_mark, "push-mark");
   DEFSYM (Qunderline, "underline");
@@ -2325,7 +2326,7 @@ syms_of_textconv (void)
           "overriding-text-conversion-style");
 
   DEFVAR_LISP ("text-conversion-edits", Vtext_conversion_edits,
-    doc: /* List of buffers that were last edited as result of text conversion.
+    doc: /* List of buffers last edited as a result of text conversion.
 
 This list can be used while handling a `text-conversion' event to
 determine which changes have taken place.