gio/gapplicationcommandline.c

   1 /*
   2  * Copyright © 2010 Codethink Limited
   3  *
   4  * This program is free software: you can redistribute it and/or modify
   5  * it under the terms of the GNU Lesser General Public License as
   6  * published by the Free Software Foundation; either version 2 of the
   7  * licence or (at your option) any later version.
   8  *
   9  * This library is distributed in the hope that it will be useful, but
  10  * WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12  * Lesser General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU Lesser General Public
  15  * License along with this library; if not, write to the Free Software
  16  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307,
  17  * USA.
  18  *
  19  * Authors: Ryan Lortie <desrt@desrt.ca>
  20  */
  21
  22 #include "config.h"
  23
  24 #include "gapplicationcommandline.h"
  25
  26 #include "glibintl.h"
  27
  28 #include <string.h>
  29 #include <stdio.h>
  30
  31 G_DEFINE_TYPE (GApplicationCommandLine, g_application_command_line, G_TYPE_OBJECT)
  32
  33 /**
  34  * SECTION:gapplicationcommandline
  35  * @title: GApplicationCommandLine
  36  * @short_description: A command-line invocation of an application
  37  * @see_also: #GApplication
  38  *
  39  * #GApplicationCommandLine represents a command-line invocation of
  40  * an application.  It is created by #GApplication and emitted
  41  * in the #GApplication::command-line signal and virtual function.
  42  *
  43  * The class contains the list of arguments that the program was invoked
  44  * with.  It is also possible to query if the commandline invocation was
  45  * local (ie: the current process is running in direct response to the
  46  * invocation) or remote (ie: some other process forwarded the
  47  * commandline to this process).
  48  *
  49  * The GApplicationCommandLine object can provide the @argc and @argv
  50  * parameters for use with the #GOptionContext command-line parsing API,
  51  * with the g_application_command_line_get_arguments() function. See
  52  * <xref linkend="gapplication-example-cmdline3"/> for an example.
  53  *
  54  * The exit status of the originally-invoked process may be set and
  55  * messages can be printed to stdout or stderr of that process.  The
  56  * lifecycle of the originally-invoked process is tied to the lifecycle
  57  * of this object (ie: the process exits when the last reference is
  58  * dropped).
  59  *
  60  * The main use for #GApplicationCommandLine (and the
  61  * #GApplication::command-line signal) is 'Emacs server' like use cases:
  62  * You can set the <envar>EDITOR</envar> environment variable to have
  63  * e.g. git use your favourite editor to edit commit messages, and if you
  64  * already have an instance of the editor running, the editing will happen
  65  * in the running instance, instead of opening a new one. An important
  66  * aspect of this use case is that the process that gets started by git
  67  * does not return until the editing is done.
  68  *
  69  * <example id="gapplication-example-cmdline"><title>Handling commandline arguments with GApplication</title>
  70  * <para>
  71  * A simple example where the commandline is completely handled
  72  * in the #GApplication::command-line handler. The launching instance exits
  73  * once the signal handler in the primary instance has returned, and the
  74  * return value of the signal handler becomes the exit status of the launching
  75  * instance.
  76  * </para>
  77  * <programlisting>
  78  * <xi:include xmlns:xi="http://www.w3.org/2001/XInclude" parse="text" href="../../../../gio/tests/gapplication-example-cmdline.c">
  79  *   <xi:fallback>FIXME: MISSING XINCLUDE CONTENT</xi:fallback>
  80  * </xi:include>
  81  * </programlisting>
  82  * </example>
  83  *
  84  * <example id="gapplication-example-cmdline2"><title>Split commandline handling</title>
  85  * <para>
  86  * An example of split commandline handling. Options that start with
  87  * <literal>--local-</literal> are handled locally, all other options are
  88  * passed to the #GApplication::command-line handler which runs in the primary
  89  * instance.
  90  * </para>
  91  * <programlisting>
  92  * <xi:include xmlns:xi="http://www.w3.org/2001/XInclude" parse="text" href="../../../../gio/tests/gapplication-example-cmdline2.c">
  93  *   <xi:fallback>FIXME: MISSING XINCLUDE CONTENT</xi:fallback>
  94  * </xi:include>
  95  * </programlisting>
  96  * </example>
  97  *
  98  * <example id="gapplication-example-cmdline3"><title>Deferred commandline handling</title>
  99  * <para>
 100  * An example of deferred commandline handling. Here, the commandline is
 101  * not completely handled before the #GApplication::command-line handler
 102  * returns. Instead, we keep a reference to the GApplicationCommandLine
 103  * object and handle it later(in this example, in an idle). Note that it
 104  * is necessary to hold the application until you are done with the
 105  * commandline.
 106  * </para>
 107  * <para>
 108  * This example also shows how to use #GOptionContext for parsing the
 109  * commandline arguments. Note that it is necessary to disable the
 110  * built-in help-handling of #GOptionContext, since it calls exit()
 111  * after printing help, which is not what you want to happen in
 112  * the primary instance.
 113  * </para>
 114  * <programlisting>
 115  * <xi:include xmlns:xi="http://www.w3.org/2001/XInclude" parse="text" href="../../../../gio/tests/gapplication-example-cmdline3.c">
 116  *   <xi:fallback>FIXME: MISSING XINCLUDE CONTENT</xi:fallback>
 117  * </xi:include>
 118  * </programlisting>
 119  * </example>
 120  **/
 121
 122 /**
 123  * GApplicationCommandLineClass:
 124  *
 125  * The <structname>GApplicationCommandLineClass</structname> structure
 126  * contains private data only
 127  *
 128  * Since: 2.28
 129  **/
 130 enum
 131 {
 132   PROP_NONE,
 133   PROP_ARGUMENTS,
 134   PROP_PLATFORM_DATA,
 135   PROP_IS_REMOTE
 136 };
 137
 138 struct _GApplicationCommandLinePrivate
 139 {
 140   GVariant *platform_data;
 141   GVariant *arguments;
 142   gchar *cwd;
 143
 144   gchar **environ;
 145   gint exit_status;
 146 };
 147
 148 /* All subclasses represent remote invocations of some kind. */
 149 #define IS_REMOTE(cmdline) (G_TYPE_FROM_INSTANCE (cmdline) != \
 150                             G_TYPE_APPLICATION_COMMAND_LINE)
 151
 152 static void
 153 grok_platform_data (GApplicationCommandLine *cmdline)
 154 {
 155   GVariantIter iter;
 156   const gchar *key;
 157   GVariant *value;
 158
 159   g_variant_iter_init (&iter, cmdline->priv->platform_data);
 160
 161   while (g_variant_iter_loop (&iter, "{&sv}", &key, &value))
 162     if (strcmp (key, "cwd") == 0)
 163       {
 164         if (!cmdline->priv->cwd)
 165           cmdline->priv->cwd = g_variant_dup_bytestring (value, NULL);
 166       }
 167
 168     else if (strcmp (key, "environ") == 0)
 169       {
 170         if (!cmdline->priv->environ)
 171           cmdline->priv->environ =
 172             g_variant_dup_bytestring_array (value, NULL);
 173       }
 174 }
 175
 176 static void
 177 g_application_command_line_real_print_literal (GApplicationCommandLine *cmdline,
 178                                                const gchar             *message)
 179 {
 180   g_print ("%s", message);
 181 }
 182
 183 static void
 184 g_application_command_line_real_printerr_literal (GApplicationCommandLine *cmdline,
 185                                                   const gchar             *message)
 186 {
 187   g_printerr ("%s", message);
 188 }
 189
 190 static void
 191 g_application_command_line_get_property (GObject    *object,
 192                                          guint       prop_id,
 193                                          GValue     *value,
 194                                          GParamSpec *pspec)
 195 {
 196   GApplicationCommandLine *cmdline = G_APPLICATION_COMMAND_LINE (object);
 197
 198   switch (prop_id)
 199     {
 200     case PROP_ARGUMENTS:
 201       g_value_set_variant (value, cmdline->priv->arguments);
 202       break;
 203
 204     case PROP_PLATFORM_DATA:
 205       g_value_set_variant (value, cmdline->priv->platform_data);
 206       break;
 207
 208     case PROP_IS_REMOTE:
 209       g_value_set_boolean (value, IS_REMOTE (cmdline));
 210       break;
 211
 212     default:
 213       g_assert_not_reached ();
 214     }
 215 }
 216
 217 static void
 218 g_application_command_line_set_property (GObject      *object,
 219                                          guint         prop_id,
 220                                          const GValue *value,
 221                                          GParamSpec   *pspec)
 222 {
 223   GApplicationCommandLine *cmdline = G_APPLICATION_COMMAND_LINE (object);
 224
 225   switch (prop_id)
 226     {
 227     case PROP_ARGUMENTS:
 228       g_assert (cmdline->priv->arguments == NULL);
 229       cmdline->priv->arguments = g_value_dup_variant (value);
 230       break;
 231
 232     case PROP_PLATFORM_DATA:
 233       g_assert (cmdline->priv->platform_data == NULL);
 234       cmdline->priv->platform_data = g_value_dup_variant (value);
 235       if (cmdline->priv->platform_data != NULL)
 236         grok_platform_data (cmdline);
 237       break;
 238
 239     default:
 240       g_assert_not_reached ();
 241     }
 242 }
 243
 244 static void
 245 g_application_command_line_finalize (GObject *object)
 246 {
 247   GApplicationCommandLine *cmdline = G_APPLICATION_COMMAND_LINE (object);
 248
 249   if (cmdline->priv->platform_data)
 250     g_variant_unref (cmdline->priv->platform_data);
 251   if (cmdline->priv->arguments)
 252     g_variant_unref (cmdline->priv->arguments);
 253
 254   g_free (cmdline->priv->cwd);
 255   g_strfreev (cmdline->priv->environ);
 256
 257   G_OBJECT_CLASS (g_application_command_line_parent_class)
 258     ->finalize (object);
 259 }
 260
 261 static void
 262 g_application_command_line_init (GApplicationCommandLine *cmdline)
 263 {
 264   cmdline->priv =
 265     G_TYPE_INSTANCE_GET_PRIVATE (cmdline,
 266                                  G_TYPE_APPLICATION_COMMAND_LINE,
 267                                  GApplicationCommandLinePrivate);
 268 }
 269
 270 static void
 271 g_application_command_line_constructed (GObject *object)
 272 {
 273   GApplicationCommandLine *cmdline = G_APPLICATION_COMMAND_LINE (object);
 274
 275   if (IS_REMOTE (cmdline))
 276     return;
 277
 278   /* In the local case, set cmd and environ */
 279   if (!cmdline->priv->cwd)
 280     cmdline->priv->cwd = g_get_current_dir ();
 281
 282   if (!cmdline->priv->environ)
 283     cmdline->priv->environ = g_get_environ ();
 284 }
 285
 286 static void
 287 g_application_command_line_class_init (GApplicationCommandLineClass *class)
 288 {
 289   GObjectClass *object_class = G_OBJECT_CLASS (class);
 290
 291   object_class->get_property = g_application_command_line_get_property;
 292   object_class->set_property = g_application_command_line_set_property;
 293   object_class->finalize = g_application_command_line_finalize;
 294   object_class->constructed = g_application_command_line_constructed;
 295
 296   class->printerr_literal = g_application_command_line_real_printerr_literal;
 297   class->print_literal = g_application_command_line_real_print_literal;
 298
 299   g_object_class_install_property (object_class, PROP_ARGUMENTS,
 300     g_param_spec_variant ("arguments",
 301                           P_("Commandline arguments"),
 302                           P_("The commandline that caused this ::command-line signal emission"),
 303                           G_VARIANT_TYPE_BYTESTRING_ARRAY, NULL,
 304                           G_PARAM_WRITABLE | G_PARAM_CONSTRUCT_ONLY |
 305                           G_PARAM_STATIC_STRINGS));
 306
 307   g_object_class_install_property (object_class, PROP_PLATFORM_DATA,
 308     g_param_spec_variant ("platform-data",
 309                           P_("Platform data"),
 310                           P_("Platform-specific data for the commandline"),
 311                           G_VARIANT_TYPE ("a{sv}"), NULL,
 312                           G_PARAM_WRITABLE | G_PARAM_CONSTRUCT_ONLY |
 313                           G_PARAM_STATIC_STRINGS));
 314
 315   g_object_class_install_property (object_class, PROP_IS_REMOTE,
 316     g_param_spec_boolean ("is-remote",
 317                           P_("Is remote"),
 318                           P_("TRUE if this is a remote commandline"),
 319                           FALSE,
 320                           G_PARAM_READABLE | G_PARAM_STATIC_STRINGS));
 321
 322   g_type_class_add_private (class, sizeof (GApplicationCommandLinePrivate));
 323 }
 324
 325
 326 /**
 327  * g_application_command_line_get_arguments:
 328  * @cmdline: a #GApplicationCommandLine
 329  * @argc: (out) (allow-none): the length of the arguments array, or %NULL
 330  *
 331  * Gets the list of arguments that was passed on the command line.
 332  *
 333  * The strings in the array may contain non-utf8 data.
 334  *
 335  * The return value is %NULL-terminated and should be freed using
 336  * g_strfreev().
 337  *
 338  * Returns: (array length=argc) (transfer full): the string array
 339  * containing the arguments (the argv)
 340  *
 341  * Since: 2.28
 342  **/
 343 gchar **
 344 g_application_command_line_get_arguments (GApplicationCommandLine *cmdline,
 345                                           int                     *argc)
 346 {
 347   gchar **argv;
 348   gsize len;
 349
 350   g_return_val_if_fail (G_IS_APPLICATION_COMMAND_LINE (cmdline), NULL);
 351
 352   argv = g_variant_dup_bytestring_array (cmdline->priv->arguments, &len);
 353
 354   if (argc)
 355     *argc = len;
 356
 357   return argv;
 358 }
 359
 360 /**
 361  * g_application_command_line_get_cwd:
 362  * @cmdline: a #GApplicationCommandLine
 363  *
 364  * Gets the working directory of the command line invocation.
 365  * The string may contain non-utf8 data.
 366  *
 367  * It is possible that the remote application did not send a working
 368  * directory, so this may be %NULL.
 369  *
 370  * The return value should not be modified or freed and is valid for as
 371  * long as @cmdline exists.
 372  *
 373  * Returns: the current directory, or %NULL
 374  *
 375  * Since: 2.28
 376  **/
 377 const gchar *
 378 g_application_command_line_get_cwd (GApplicationCommandLine *cmdline)
 379 {
 380   return cmdline->priv->cwd;
 381 }
 382
 383 /**
 384  * g_application_command_line_get_environ:
 385  * @cmdline: a #GApplicationCommandLine
 386  *
 387  * Gets the contents of the 'environ' variable of the command line
 388  * invocation, as would be returned by g_get_environ(), ie as a
 389  * %NULL-terminated list of strings in the form 'NAME=VALUE'.
 390  * The strings may contain non-utf8 data.
 391  *
 392  * The remote application usually does not send an environment.  Use
 393  * %G_APPLICATION_SEND_ENVIRONMENT to affect that.  Even with this flag
 394  * set it is possible that the environment is still not available (due
 395  * to invocation messages from other applications).
 396  *
 397  * The return value should not be modified or freed and is valid for as
 398  * long as @cmdline exists.
 399  *
 400  * See g_application_command_line_getenv() if you are only interested
 401  * in the value of a single environment variable.
 402  *
 403  * Returns: (array zero-terminated=1) (transfer none): the environment
 404  * strings, or %NULL if they were not sent
 405  *
 406  * Since: 2.28
 407  **/
 408 const gchar * const *
 409 g_application_command_line_get_environ (GApplicationCommandLine *cmdline)
 410 {
 411   return (const gchar **)cmdline->priv->environ;
 412 }
 413
 414 /**
 415  * g_application_command_line_getenv:
 416  * @cmdline: a #GApplicationCommandLine
 417  * @name: the environment variable to get
 418  *
 419  * Gets the value of a particular environment variable of the command
 420  * line invocation, as would be returned by g_getenv().  The strings may
 421  * contain non-utf8 data.
 422  *
 423  * The remote application usually does not send an environment.  Use
 424  * %G_APPLICATION_SEND_ENVIRONMENT to affect that.  Even with this flag
 425  * set it is possible that the environment is still not available (due
 426  * to invocation messages from other applications).
 427  *
 428  * The return value should not be modified or freed and is valid for as
 429  * long as @cmdline exists.
 430  *
 431  * Returns: the value of the variable, or %NULL if unset or unsent
 432  *
 433  * Since: 2.28
 434  **/
 435 const gchar *
 436 g_application_command_line_getenv (GApplicationCommandLine *cmdline,
 437                                    const gchar             *name)
 438 {
 439   gint length = strlen (name);
 440   gint i;
 441
 442   /* TODO: expand on windows */
 443   if (cmdline->priv->environ)
 444     for (i = 0; cmdline->priv->environ[i]; i++)
 445       if (strncmp (cmdline->priv->environ[i], name, length) == 0 &&
 446           cmdline->priv->environ[i][length] == '=')
 447         return cmdline->priv->environ[i] + length + 1;
 448
 449   return NULL;
 450 }
 451
 452 /**
 453  * g_application_command_line_get_is_remote:
 454  * @cmdline: a #GApplicationCommandLine
 455  *
 456  * Determines if @cmdline represents a remote invocation.
 457  *
 458  * Returns: %TRUE if the invocation was remote
 459  *
 460  * Since: 2.28
 461  **/
 462 gboolean
 463 g_application_command_line_get_is_remote (GApplicationCommandLine *cmdline)
 464 {
 465   return IS_REMOTE (cmdline);
 466 }
 467
 468 /**
 469  * g_application_command_line_print:
 470  * @cmdline: a #GApplicationCommandLine
 471  * @format: a printf-style format string
 472  * @...: arguments, as per @format
 473  *
 474  * Formats a message and prints it using the stdout print handler in the
 475  * invoking process.
 476  *
 477  * If @cmdline is a local invocation then this is exactly equivalent to
 478  * g_print().  If @cmdline is remote then this is equivalent to calling
 479  * g_print() in the invoking process.
 480  *
 481  * Since: 2.28
 482  **/
 483 void
 484 g_application_command_line_print (GApplicationCommandLine *cmdline,
 485                                   const gchar             *format,
 486                                   ...)
 487 {
 488   gchar *message;
 489   va_list ap;
 490
 491   g_return_if_fail (G_IS_APPLICATION_COMMAND_LINE (cmdline));
 492   g_return_if_fail (format != NULL);
 493
 494   va_start (ap, format);
 495   message = g_strdup_vprintf (format, ap);
 496   va_end (ap);
 497
 498   G_APPLICATION_COMMAND_LINE_GET_CLASS (cmdline)
 499     ->print_literal (cmdline, message);
 500   g_free (message);
 501 }
 502
 503 /**
 504  * g_application_command_line_printerr:
 505  * @cmdline: a #GApplicationCommandLine
 506  * @format: a printf-style format string
 507  * @...: arguments, as per @format
 508  *
 509  * Formats a message and prints it using the stderr print handler in the
 510  * invoking process.
 511  *
 512  * If @cmdline is a local invocation then this is exactly equivalent to
 513  * g_printerr().  If @cmdline is remote then this is equivalent to
 514  * calling g_printerr() in the invoking process.
 515  *
 516  * Since: 2.28
 517  **/
 518 void
 519 g_application_command_line_printerr (GApplicationCommandLine *cmdline,
 520                                      const gchar             *format,
 521                                      ...)
 522 {
 523   gchar *message;
 524   va_list ap;
 525
 526   g_return_if_fail (G_IS_APPLICATION_COMMAND_LINE (cmdline));
 527   g_return_if_fail (format != NULL);
 528
 529   va_start (ap, format);
 530   message = g_strdup_vprintf (format, ap);
 531   va_end (ap);
 532
 533   G_APPLICATION_COMMAND_LINE_GET_CLASS (cmdline)
 534     ->printerr_literal (cmdline, message);
 535   g_free (message);
 536 }
 537
 538 /**
 539  * g_application_command_line_set_exit_status:
 540  * @cmdline: a #GApplicationCommandLine
 541  * @exit_status: the exit status
 542  *
 543  * Sets the exit status that will be used when the invoking process
 544  * exits.
 545  *
 546  * The return value of the #GApplication::command-line signal is
 547  * passed to this function when the handler returns.  This is the usual
 548  * way of setting the exit status.
 549  *
 550  * In the event that you want the remote invocation to continue running
 551  * and want to decide on the exit status in the future, you can use this
 552  * call.  For the case of a remote invocation, the remote process will
 553  * typically exit when the last reference is dropped on @cmdline.  The
 554  * exit status of the remote process will be equal to the last value
 555  * that was set with this function.
 556  *
 557  * In the case that the commandline invocation is local, the situation
 558  * is slightly more complicated.  If the commandline invocation results
 559  * in the mainloop running (ie: because the use-count of the application
 560  * increased to a non-zero value) then the application is considered to
 561  * have been 'successful' in a certain sense, and the exit status is
 562  * always zero.  If the application use count is zero, though, the exit
 563  * status of the local #GApplicationCommandLine is used.
 564  *
 565  * Since: 2.28
 566  **/
 567 void
 568 g_application_command_line_set_exit_status (GApplicationCommandLine *cmdline,
 569                                             int                      exit_status)
 570 {
 571   g_return_if_fail (G_IS_APPLICATION_COMMAND_LINE (cmdline));
 572
 573   cmdline->priv->exit_status = exit_status;
 574 }
 575
 576 /**
 577  * g_application_command_line_get_exit_status:
 578  * @cmdline: a #GApplicationCommandLine
 579  *
 580  * Gets the exit status of @cmdline.  See
 581  * g_application_command_line_set_exit_status() for more information.
 582  *
 583  * Returns: the exit status
 584  *
 585  * Since: 2.28
 586  **/
 587 int
 588 g_application_command_line_get_exit_status (GApplicationCommandLine *cmdline)
 589 {
 590   g_return_val_if_fail (G_IS_APPLICATION_COMMAND_LINE (cmdline), -1);
 591
 592   return cmdline->priv->exit_status;
 593 }
 594
 595 /**
 596  * g_application_command_line_get_platform_data:
 597  * @cmdline: #GApplicationCommandLine
 598  *
 599  * Gets the platform data associated with the invocation of @cmdline.
 600  *
 601  * This is a #GVariant dictionary containing information about the
 602  * context in which the invocation occurred.  It typically contains
 603  * information like the current working directory and the startup
 604  * notification ID.
 605  *
 606  * For local invocation, it will be %NULL.
 607  *
 608  * Returns: (allow-none): the platform data, or %NULL
 609  *
 610  * Since: 2.28
 611  **/
 612 GVariant *
 613 g_application_command_line_get_platform_data (GApplicationCommandLine *cmdline)
 614 {
 615   g_return_val_if_fail (G_IS_APPLICATION_COMMAND_LINE (cmdline), NULL);
 616
 617   if (cmdline->priv->platform_data)
 618     return g_variant_ref (cmdline->priv->platform_data);
 619   else
 620       return NULL;
 621 }