Implement bash completion for gsettings

gio/Makefile.am

@@ -590,7 +590,9 @@ gdbus_LDADD = libgio-2.0.la \
 	$(top_builddir)/gobject/libgobject-2.0.la
 
 completiondir = $(sysconfdir)/bash_completion.d
-completion_SCRIPTS = gdbus-bash-completion.sh
+completion_SCRIPTS = \
+	gdbus-bash-completion.sh		\
+	gsettings-bash-completion.sh
 EXTRA_DIST += $(completion_SCRIPTS)
 
 # ------------------------------------------------------------------------

gio/gsettings-bash-completion.sh

@@ -0,0 +1,33 @@
+
+# Check for bash
+[ -z "$BASH_VERSION" ] && return
+
+####################################################################################################
+
+
+__gsettings() {
+    local IFS=$'\n'
+    local cur=`_get_cword :`
+
+    local suggestions=$(gsettings complete "${COMP_LINE}" ${COMP_POINT})
+    COMPREPLY=($(compgen -W "$suggestions" -- "$cur"))
+
+    # Remove colon-word prefix from COMPREPLY items
+    case "$cur" in
+        *:*)
+            case "$COMP_WORDBREAKS" in
+                *:*)
+                    local colon_word=${cur%${cur##*:}}
+                    local i=${#COMPREPLY[*]}
+                    while [ $((--i)) -ge 0 ]; do
+                        COMPREPLY[$i]=${COMPREPLY[$i]#"$colon_word"}
+                    done
+                    ;;
+            esac
+            ;;
+    esac
+}
+
+####################################################################################################
+
+complete -o nospace -F __gsettings gsettings

gio/gsettings-tool.c

@@ -21,10 +21,48 @@
 
 #include "config.h"
 
+#include <stdlib.h>
+#include <stdio.h>
 #include <locale.h>
 #include <gi18n.h>
 #include <gio.h>
 
+static gchar *
+pick_word_at (const gchar  *s,
+              gint          cursor,
+              gint         *out_word_begins_at)
+{
+  gint begin;
+  gint end;
+
+  if (s[0] == '\0')
+    {
+      if (out_word_begins_at != NULL)
+        *out_word_begins_at = -1;
+      return NULL;
+    }
+
+  if (g_ascii_isspace (s[cursor]) &&
+      ((cursor > 0 && g_ascii_isspace (s[cursor-1])) || cursor == 0))
+    {
+      if (out_word_begins_at != NULL)
+        *out_word_begins_at = cursor;
+      return g_strdup ("");
+    }
+  while (!g_ascii_isspace (s[cursor - 1]) && cursor > 0)
+    cursor--;
+  begin = cursor;
+
+  end = begin;
+  while (!g_ascii_isspace (s[end]) && s[end] != '\0')
+    end++;
+
+  if (out_word_begins_at != NULL)
+    *out_word_begins_at = begin;
+
+  return g_strndup (s + begin, end - begin);
+}
+
 static gint
 usage (gint      *argc,
        gchar    **argv[],
@@ -73,6 +111,7 @@ remove_arg (gint num, gint *argc, gchar **argv[])
   (*argc) = (*argc) - 1;
 }
 
+
 static void
 modify_argv0_for_command (gint         *argc,
                           gchar       **argv[],
@@ -87,10 +126,86 @@ modify_argv0_for_command (gint         *argc,
   (*argv)[0] = s;
 }
 
+static gboolean
+schema_exists (const gchar *name)
+{
+  const gchar * const *schemas;
+  gint i;
+
+  schemas = g_settings_list_schemas ();
+  for (i = 0; schemas[i]; i++)
+    if (g_strcmp0 (name, schemas[i]) == 0)
+      return TRUE;
+
+  return FALSE;
+}
+
+static void
+list_schemas (const gchar *prefix)
+{
+  const gchar * const *schemas;
+  gint i;
+
+  schemas = g_settings_list_schemas ();
+  for (i = 0; schemas[i]; i++)
+    if (prefix == NULL || g_str_has_prefix (schemas[i], prefix))
+      g_print ("%s \n", schemas[i]);
+}
+
+static gboolean
+key_exists (GSettings   *settings,
+            const gchar *name)
+{
+  const gchar **keys;
+  gint i;
+  gboolean ret;
+
+  ret = FALSE;
+
+  keys = g_settings_list_keys (settings);
+  for (i = 0; keys[i]; i++)
+    if (g_strcmp0 (keys[i], name) == 0)
+      {
+        ret = TRUE;
+        break;
+      }
+  g_free (keys);
+
+  return ret;
+}
+
+static void
+list_keys (GSettings   *settings,
+           const gchar *prefix)
+{
+  const gchar **keys;
+  gint i;
+
+  keys = g_settings_list_keys (settings);
+  for (i = 0; keys[i]; i++)
+    if (prefix == NULL || g_str_has_prefix (keys[i], prefix))
+      g_print ("%s \n", keys[i]);
+  g_free (keys);
+}
+
+static void
+list_options (GOptionContext *context,
+              const gchar    *prefix)
+{
+  /* FIXME extract options from context */
+  const gchar *options[] = { "--help", "--path", NULL };
+  gint i;
+  for (i = 0; options[i]; i++)
+    if (g_str_has_prefix (options[i], prefix))
+      g_print ("%s \n", options[i]);
+}
 
 static gint
 handle_get (gint      *argc,
-            gchar **argv[])
+            gchar    **argv[],
+            gboolean   request_completion,
+            gchar     *completion_cur,
+            gchar     *completion_prev)
 {
   gchar *schema;
   gchar *path;
@@ -116,10 +231,15 @@ handle_get (gint   *argc,
       "  KEY         The name of the key\n"));
   g_option_context_add_main_entries (context, entries, GETTEXT_PACKAGE);
 
+  settings = NULL;
   path = NULL;
+  schema = NULL;
+  key = NULL;
 
   error = NULL;
-  if (!g_option_context_parse (context, argc, argv, NULL) || *argc != 3)
+  if (!g_option_context_parse (context, argc, argv, NULL))
+    {
+      if (!request_completion)
         {
           gchar *s;
           s = g_option_context_get_help (context, FALSE, NULL);
@@ -128,21 +248,51 @@ handle_get (gint   *argc,
 
           goto out;
         }
+    }
 
+  if (*argc > 1)
     schema = (*argv)[1];
+  if (*argc > 2)
     key = (*argv)[2];
 
+  if (request_completion && completion_cur[0] == '-')
+    {
+      list_options (context, completion_cur);
+      ret = 0;
+      goto out;
+    }
+
+  if (request_completion && !schema_exists (schema))
+    {
+      list_schemas (schema);
+      ret = 0;
+      goto out;
+    }
+
   if (path)
     settings = g_settings_new_with_path (schema, path);
   else
     settings = g_settings_new (schema);
 
+  if (request_completion && !key_exists (settings, key))
+    {
+      list_keys (settings, key);
+      ret = 0;
+      goto out;
+    }
+
+  if (!request_completion)
+    {
       v = g_settings_get_value (settings, key);
       g_print ("%s\n", g_variant_print (v, FALSE));
       g_variant_unref (v);
       ret = 0;
+    }
 
  out:
+  if (settings)
+    g_object_unref (settings);
+
   g_option_context_free (context);
 
   return ret;
@@ -150,7 +300,10 @@ handle_get (gint   *argc,
 
 static gint
 handle_set (gint      *argc,
-            gchar **argv[])
+            gchar    **argv[],
+            gboolean   request_completion,
+            gchar     *completion_cur,
+            gchar     *completion_prev)
 {
   gchar *schema;
   gchar *path;
@@ -179,28 +332,59 @@ handle_set (gint   *argc,
       "  VALUE       The value to set key to, as a serialized GVariant\n"));
   g_option_context_add_main_entries (context, entries, GETTEXT_PACKAGE);
 
+  settings = NULL;
   path = NULL;
+  schema = NULL;
+  key = NULL;
 
   error = NULL;
-  if (!g_option_context_parse (context, argc, argv, NULL) || *argc != 4)
+  if (!g_option_context_parse (context, argc, argv, NULL))
+    {
+      if (!request_completion)
         {
           gchar *s;
           s = g_option_context_get_help (context, FALSE, NULL);
           g_printerr ("%s", s);
           g_free (s);
+          goto out;
+        }
+    }
 
+  if (*argc > 1)
+    schema = (*argv)[1];
+  if (*argc > 2)
+    key = (*argv)[2];
+  if (*argc > 3)
+    value = (*argv)[3];
+
+  if (request_completion && completion_cur[0] == '-')
+    {
+      list_options (context, completion_cur);
+      ret = 0;
       goto out;
     }
 
-  schema = (*argv)[1];
+  if (request_completion && !schema_exists (schema))
-  key = (*argv)[2];
+    {
-  value = (*argv)[3];
+      list_schemas (schema);
+      ret = 0;
+      goto out;
+    }
 
   if (path)
     settings = g_settings_new_with_path (schema, path);
   else
     settings = g_settings_new (schema);
 
+  if (request_completion && !key_exists (settings, key))
+    {
+      list_keys (settings, key);
+      ret = 0;
+      goto out;
+    }
+
+  if (!request_completion)
+    {
       default_v = g_settings_get_value (settings, key);
       type = g_variant_get_type (default_v);
 
@@ -221,8 +405,12 @@ handle_set (gint   *argc,
 
       g_settings_sync ();
       ret = 0;
+    }
 
  out:
+  if (settings)
+    g_object_unref (settings);
+
   g_option_context_free (context);
 
   return ret;
@@ -230,7 +418,10 @@ handle_set (gint   *argc,
 
 static gint
 handle_writable (gint   *argc,
-                 gchar **argv[])
+                 gchar **argv[],
+                 gboolean   request_completion,
+                 gchar     *completion_cur,
+                 gchar     *completion_prev)
 {
   gchar *schema;
   gchar *path;
@@ -255,34 +446,68 @@ handle_writable (gint   *argc,
       "  KEY         The name of the key\n"));
   g_option_context_add_main_entries (context, entries, GETTEXT_PACKAGE);
 
+  settings = NULL;
   path = NULL;
+  schema = NULL;
+  key = NULL;
 
   error = NULL;
-  if (!g_option_context_parse (context, argc, argv, NULL) || *argc != 3)
+  if (!g_option_context_parse (context, argc, argv, NULL))
+    {
+      if (!request_completion)
         {
           gchar *s;
           s = g_option_context_get_help (context, FALSE, NULL);
           g_printerr ("%s", s);
           g_free (s);
+          goto out;
+        }
+    }
 
+  if (*argc > 1)
+    schema = (*argv)[1];
+  if (*argc > 2)
+    key = (*argv)[2];
+
+  if (request_completion && completion_cur[0] == '-')
+    {
+      list_options (context, completion_cur);
+      ret = 0;
       goto out;
     }
 
-  schema = (*argv)[1];
+  if (request_completion && !schema_exists (schema))
-  key = (*argv)[2];
+    {
+      list_schemas (schema);
+      ret = 0;
+      goto out;
+    }
 
   if (path)
     settings = g_settings_new_with_path (schema, path);
   else
     settings = g_settings_new (schema);
 
+  if (request_completion && !key_exists (settings, key))
+    {
+      list_keys (settings, key);
+      ret = 0;
+      goto out;
+    }
+
+  if (!request_completion)
+    {
       if (g_settings_is_writable (settings, key))
         g_print ("true\n");
       else
         g_print ("false\n");
       ret = 0;
+    }
 
  out:
+  if (settings)
+    g_object_unref (settings);
+
   g_option_context_free (context);
 
   return ret;
@@ -304,7 +529,10 @@ key_changed (GSettings   *settings,
 
 static gint
 handle_monitor (gint      *argc,
-                gchar **argv[])
+                gchar    **argv[],
+                gboolean   request_completion,
+                gchar     *completion_cur,
+                gchar     *completion_prev)
 {
   gchar *schema;
   gchar *path;
@@ -334,27 +562,57 @@ handle_monitor (gint   *argc,
       "  KEY         The name of the key\n"));
   g_option_context_add_main_entries (context, entries, GETTEXT_PACKAGE);
 
+  settings = NULL;
   path = NULL;
+  schema = NULL;
+  key = NULL;
 
   error = NULL;
-  if (!g_option_context_parse (context, argc, argv, NULL) || *argc != 3)
+  if (!g_option_context_parse (context, argc, argv, NULL))
+    {
+      if (!request_completion)
         {
           gchar *s;
           s = g_option_context_get_help (context, FALSE, NULL);
           g_printerr ("%s", s);
           g_free (s);
+          goto out;
+        }
+    }
 
+  if (*argc > 1)
+    schema = (*argv)[1];
+  if (*argc > 2)
+    key = (*argv)[2];
+
+  if (request_completion && completion_cur[0] == '-')
+    {
+      list_options (context, completion_cur);
+      ret = 0;
       goto out;
     }
 
-  schema = (*argv)[1];
+  if (request_completion && !schema_exists (schema))
-  key = (*argv)[2];
+    {
+      list_schemas (schema);
+      ret = 0;
+      goto out;
+    }
 
   if (path)
     settings = g_settings_new_with_path (schema, path);
   else
     settings = g_settings_new (schema);
 
+  if (request_completion && !key_exists (settings, key))
+    {
+      list_keys (settings, key);
+      ret = 0;
+      goto out;
+    }
+
+  if (!request_completion)
+    {
       detailed_signal = g_strdup_printf ("changed::%s", key);
       g_signal_connect (settings, detailed_signal,
                         G_CALLBACK (key_changed), NULL);
@@ -362,8 +620,13 @@ handle_monitor (gint   *argc,
       loop = g_main_loop_new (NULL, FALSE);
       g_main_loop_run (loop);
       g_main_loop_unref (loop);
+      ret = 0;
+    }
 
  out:
+  if (settings)
+    g_object_unref (settings);
+
   g_option_context_free (context);
 
   return ret;
@@ -371,29 +634,106 @@ handle_monitor (gint   *argc,
 int
 main (int argc, char *argv[])
 {
-  gboolean ret = 1;
+  gboolean ret;
+  gchar *command;
+  gboolean request_completion;
+  gchar *completion_cur;
+  gchar *completion_prev;
 
   setlocale (LC_ALL, "");
 
   g_type_init ();
 
+  ret = 1;
+  completion_cur = NULL;
+  completion_prev = NULL;
+  request_completion = FALSE;
+
   if (argc < 2)
+    {
       ret = usage (&argc, &argv, FALSE);
-  else if (g_strcmp0 (argv[1], "help") == 0)
+      goto out;
+    }
+
+ again:
+  command = argv[1];
+
+  if (g_strcmp0 (command, "help") == 0)
+    {
+      if (!request_completion)
         ret = usage (&argc, &argv, TRUE);
-  else if (g_strcmp0 (argv[1], "get") == 0)
+    }
-    ret = handle_get (&argc, &argv);
+  else if (g_strcmp0 (command, "get") == 0)
-  else if (g_strcmp0 (argv[1], "set") == 0)
+    ret = handle_get (&argc, &argv, request_completion, completion_cur, completion_prev);
-    ret = handle_set (&argc, &argv);
+  else if (g_strcmp0 (command, "set") == 0)
-  else if (g_strcmp0 (argv[1], "monitor") == 0)
+    ret = handle_set (&argc, &argv, request_completion, completion_cur, completion_prev);
-    ret = handle_monitor (&argc, &argv);
+  else if (g_strcmp0 (command, "monitor") == 0)
-  else if (g_strcmp0 (argv[1], "writable") == 0)
+    ret = handle_monitor (&argc, &argv, request_completion, completion_cur, completion_prev);
-    ret = handle_writable (&argc, &argv);
+  else if (g_strcmp0 (command, "writable") == 0)
+    ret = handle_writable (&argc, &argv, request_completion, completion_cur, completion_prev);
+  else if (g_strcmp0 (command, "complete") == 0 && argc == 4 && !request_completion)
+    {
+      gchar *completion_line;
+      gint completion_point;
+      gchar *endp;
+      gchar **completion_argv;
+      gint completion_argc;
+      gint cur_begin;
+
+      request_completion = TRUE;
+
+      completion_line = argv[2];
+      completion_point = strtol (argv[3], &endp, 10);
+      if (endp == argv[3] || *endp != '\0')
+        goto out;
+
+      if (!g_shell_parse_argv (completion_line,
+                               &completion_argc,
+                               &completion_argv,
+                               NULL))
+        {
+          /* can't parse partical cmdline, don't attempt completion */
+          goto out;
+        }
+
+      completion_prev = NULL;
+      completion_cur = pick_word_at (completion_line, completion_point, &cur_begin);
+      if (cur_begin > 0)
+        {
+          gint prev_end;
+          for (prev_end = cur_begin - 1; prev_end >= 0; prev_end--)
+            {
+              if (!g_ascii_isspace (completion_line[prev_end]))
+                {
+                  completion_prev = pick_word_at (completion_line, prev_end, NULL);
+                  break;
+                }
+            }
+        }
+
+      argc = completion_argc;
+      argv = completion_argv;
+
+      ret = 0;
+      goto again;
+    }
+  else
+    {
+      if (request_completion)
+        {
+          g_print ("help \nget \nmonitor \nwritable \nset \n");
+          ret = 0;
+        }
       else
         {
           g_printerr (_("Unknown command '%s'\n"), argv[1]);
           ret = usage (&argc, &argv, FALSE);
         }
+    }
+
+ out:
+  g_free (completion_cur);
+  g_free (completion_prev);
 
   return ret;
 }