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 enum
 123 {
 124   PROP_NONE,
 125   PROP_ARGUMENTS,
 126   PROP_PLATFORM_DATA,
 127   PROP_IS_REMOTE
 128 };
 129
 130 struct _GApplicationCommandLinePrivate
 131 {
 132   GVariant *platform_data;
 133   GVariant *arguments;
 134   GVariant *cwd;
 135
 136   const gchar **environ;
 137   gint exit_status;
 138 };
 139
 140 /* All subclasses represent remote invocations of some kind. */
 141 #define IS_REMOTE(cmdline) (G_TYPE_FROM_INSTANCE (cmdline) != \
 142                             G_TYPE_APPLICATION_COMMAND_LINE)
 143
 144 static void
 145 grok_platform_data (GApplicationCommandLine *cmdline)
 146 {
 147   GVariantIter iter;
 148   const gchar *key;
 149   GVariant *value;
 150
 151   g_variant_iter_init (&iter, cmdline->priv->platform_data);
 152
 153   while (g_variant_iter_loop (&iter, "{&sv}", &key, &value))
 154     if (strcmp (key, "cwd") == 0)
 155       {
 156         if (!cmdline->priv->cwd)
 157           cmdline->priv->cwd = g_variant_ref (value);
 158       }
 159
 160     else if (strcmp (key, "environ") == 0)
 161       {
 162         if (!cmdline->priv->environ)
 163           cmdline->priv->environ =
 164             g_variant_get_bytestring_array (value, NULL);
 165       }
 166 }
 167
 168 static void
 169 g_application_command_line_real_print_literal (GApplicationCommandLine *cmdline,
 170                                                const gchar             *message)
 171 {
 172   g_print ("%s\n", message);
 173 }
 174
 175 static void
 176 g_application_command_line_real_printerr_literal (GApplicationCommandLine *cmdline,
 177                                                   const gchar             *message)
 178 {
 179   g_printerr ("%s\n", message);
 180 }
 181
 182 static void
 183 g_application_command_line_get_property (GObject    *object,
 184                                          guint       prop_id,
 185                                          GValue     *value,
 186                                          GParamSpec *pspec)
 187 {
 188   GApplicationCommandLine *cmdline = G_APPLICATION_COMMAND_LINE (object);
 189
 190   switch (prop_id)
 191     {
 192     case PROP_ARGUMENTS:
 193       g_value_set_variant (value, cmdline->priv->arguments);
 194       break;
 195
 196     case PROP_PLATFORM_DATA:
 197       g_value_set_variant (value, cmdline->priv->platform_data);
 198       break;
 199
 200     case PROP_IS_REMOTE:
 201       g_value_set_boolean (value, IS_REMOTE (cmdline));
 202       break;
 203
 204     default:
 205       g_assert_not_reached ();
 206     }
 207 }
 208
 209 static void
 210 g_application_command_line_set_property (GObject      *object,
 211                                          guint         prop_id,
 212                                          const GValue *value,
 213                                          GParamSpec   *pspec)
 214 {
 215   GApplicationCommandLine *cmdline = G_APPLICATION_COMMAND_LINE (object);
 216
 217   switch (prop_id)
 218     {
 219     case PROP_ARGUMENTS:
 220       g_assert (cmdline->priv->arguments == NULL);
 221       cmdline->priv->arguments = g_value_dup_variant (value);
 222       break;
 223
 224     case PROP_PLATFORM_DATA:
 225       g_assert (cmdline->priv->platform_data == NULL);
 226       cmdline->priv->platform_data = g_value_dup_variant (value);
 227       if (cmdline->priv->platform_data != NULL)
 228         grok_platform_data (cmdline);
 229       break;
 230
 231     default:
 232       g_assert_not_reached ();
 233     }
 234 }
 235
 236 static void
 237 g_application_command_line_finalize (GObject *object)
 238 {
 239   GApplicationCommandLine *cmdline = G_APPLICATION_COMMAND_LINE (object);
 240
 241   if (cmdline->priv->platform_data)
 242     g_variant_unref (cmdline->priv->platform_data);
 243   if (cmdline->priv->arguments)
 244     g_variant_unref (cmdline->priv->arguments);
 245   if (cmdline->priv->cwd)
 246     g_variant_unref (cmdline->priv->cwd);
 247
 248   G_OBJECT_CLASS (g_application_command_line_parent_class)
 249     ->finalize (object);
 250 }
 251
 252 static void
 253 g_application_command_line_init (GApplicationCommandLine *cmdline)
 254 {
 255   cmdline->priv =
 256     G_TYPE_INSTANCE_GET_PRIVATE (cmdline,
 257                                  G_TYPE_APPLICATION_COMMAND_LINE,
 258                                  GApplicationCommandLinePrivate);
 259 }
 260
 261 static void
 262 g_application_command_line_class_init (GApplicationCommandLineClass *class)
 263 {
 264   GObjectClass *object_class = G_OBJECT_CLASS (class);
 265
 266   object_class->get_property = g_application_command_line_get_property;
 267   object_class->set_property = g_application_command_line_set_property;
 268   object_class->finalize = g_application_command_line_finalize;
 269   class->printerr_literal = g_application_command_line_real_printerr_literal;
 270   class->print_literal = g_application_command_line_real_print_literal;
 271
 272   g_object_class_install_property (object_class, PROP_ARGUMENTS,
 273     g_param_spec_variant ("arguments",
 274                           P_("Commandline arguments"),
 275                           P_("The commandline that caused this ::command-line signal emission"),
 276                           G_VARIANT_TYPE_BYTESTRING_ARRAY, NULL,
 277                           G_PARAM_WRITABLE | G_PARAM_CONSTRUCT_ONLY |
 278                           G_PARAM_STATIC_STRINGS));
 279
 280   g_object_class_install_property (object_class, PROP_PLATFORM_DATA,
 281     g_param_spec_variant ("platform-data",
 282                           P_("Platform data"),
 283                           P_("Platform-specific data for the commandline"),
 284                           G_VARIANT_TYPE ("a{sv}"), NULL,
 285                           G_PARAM_WRITABLE | G_PARAM_CONSTRUCT_ONLY |
 286                           G_PARAM_STATIC_STRINGS));
 287
 288   g_object_class_install_property (object_class, PROP_IS_REMOTE,
 289     g_param_spec_boolean ("is-remote",
 290                           P_("Is remote"),
 291                           P_("TRUE if this is a remote commandline"),
 292                           FALSE,
 293                           G_PARAM_READABLE | G_PARAM_STATIC_STRINGS));
 294
 295   g_type_class_add_private (class, sizeof (GApplicationCommandLinePrivate));
 296 }
 297
 298
 299 /**
 300  * g_application_command_line_get_arguments:
 301  * @cmdline: a #GApplicationCommandLine
 302  * @argc: (out): the length of the arguments array, or %NULL
 303  *
 304  * Gets the list of arguments that was passed on the command line.
 305  *
 306  * The strings in the array may contain non-utf8 data.
 307  *
 308  * The return value is %NULL-terminated and should be freed using
 309  * g_strfreev().
 310  *
 311  * Returns: (array length=argc) (transfer full): the string array
 312  * containing the arguments (the argv)
 313  *
 314  * Since: 2.28
 315  **/
 316 gchar **
 317 g_application_command_line_get_arguments (GApplicationCommandLine *cmdline,
 318                                           int                     *argc)
 319 {
 320   gchar **argv;
 321   gsize len;
 322
 323   g_return_val_if_fail (G_IS_APPLICATION_COMMAND_LINE (cmdline), NULL);
 324
 325   argv = g_variant_dup_bytestring_array (cmdline->priv->arguments, &len);
 326
 327   if (argc)
 328     *argc = len;
 329
 330   return argv;
 331 }
 332
 333 /**
 334  * g_application_command_line_get_cwd:
 335  * @cmdline: a #GApplicationCommandLine
 336  *
 337  * Gets the working directory of the command line invocation.
 338  * The string may contain non-utf8 data.
 339  *
 340  * It is possible that the remote application did not send a working
 341  * directory, so this may be %NULL.
 342  *
 343  * The return value should not be modified or freed and is valid for as
 344  * long as @cmdline exists.
 345  *
 346  * Returns: the current directory, or %NULL
 347  *
 348  * Since: 2.28
 349  **/
 350 const gchar *
 351 g_application_command_line_get_cwd (GApplicationCommandLine *cmdline)
 352 {
 353   if (cmdline->priv->cwd)
 354     return g_variant_get_bytestring (cmdline->priv->cwd);
 355   else
 356     return NULL;
 357 }
 358
 359 /**
 360  * g_application_command_line_get_environ:
 361  * @cmdline: a #GApplicationCommandLine
 362  *
 363  * Gets the contents of the 'environ' variable of the command line
 364  * invocation, as would be returned by g_get_environ(), ie as a
 365  * %NULL-terminated list of strings in the form 'NAME=VALUE'.
 366  * The strings may contain non-utf8 data.
 367  *
 368  * The remote application usually does not send an environment.  Use
 369  * %G_APPLICATION_SEND_ENVIRONMENT to affect that.  Even with this flag
 370  * set it is possible that the environment is still not available (due
 371  * to invocation messages from other applications).
 372  *
 373  * The return value should not be modified or freed and is valid for as
 374  * long as @cmdline exists.
 375  *
 376  * See g_application_command_line_getenv() if you are only interested
 377  * in the value of a single environment variable.
 378  *
 379  * Returns: (array zero-terminated=1) (transfer none): the environment
 380  * strings, or %NULL if they were not sent
 381  *
 382  * Since: 2.28
 383  **/
 384 const gchar * const *
 385 g_application_command_line_get_environ (GApplicationCommandLine *cmdline)
 386 {
 387   return cmdline->priv->environ;
 388 }
 389
 390 /**
 391  * g_application_command_line_getenv:
 392  * @cmdline: a #GApplicationCommandLine
 393  * @name: the environment variable to get
 394  *
 395  * Gets the value of a particular environment variable of the command
 396  * line invocation, as would be returned by g_getenv().  The strings may
 397  * contain non-utf8 data.
 398  *
 399  * The remote application usually does not send an environment.  Use
 400  * %G_APPLICATION_SEND_ENVIRONMENT to affect that.  Even with this flag
 401  * set it is possible that the environment is still not available (due
 402  * to invocation messages from other applications).
 403  *
 404  * The return value should not be modified or freed and is valid for as
 405  * long as @cmdline exists.
 406  *
 407  * Returns: the value of the variable, or %NULL if unset or unsent
 408  *
 409  * Since: 2.28
 410  **/
 411 const gchar *
 412 g_application_command_line_getenv (GApplicationCommandLine *cmdline,
 413                                    const gchar             *name)
 414 {
 415   gint length = strlen (name);
 416   gint i;
 417
 418   /* TODO: expand on windows */
 419   if (cmdline->priv->environ)
 420     for (i = 0; cmdline->priv->environ[i]; i++)
 421       if (strncmp (cmdline->priv->environ[i], name, length) == 0 &&
 422           cmdline->priv->environ[i][length] == '=')
 423         return cmdline->priv->environ[i] + length + 1;
 424
 425   return NULL;
 426 }
 427
 428 /**
 429  * g_application_command_line_get_is_remote:
 430  * @cmdline: a #GApplicationCommandLine
 431  *
 432  * Determines if @cmdline represents a remote invocation.
 433  *
 434  * Returns: %TRUE if the invocation was remote
 435  *
 436  * Since: 2.28
 437  **/
 438 gboolean
 439 g_application_command_line_get_is_remote (GApplicationCommandLine *cmdline)
 440 {
 441   return IS_REMOTE (cmdline);
 442 }
 443
 444 /**
 445  * g_application_command_line_print:
 446  * @cmdline: a #GApplicationCommandLine
 447  * @format: a printf-style format string
 448  * @...: arguments, as per @format
 449  *
 450  * Formats a message and prints it using the stdout print handler in the
 451  * invoking process.
 452  *
 453  * If @cmdline is a local invocation then this is exactly equivalent to
 454  * g_print().  If @cmdline is remote then this is equivalent to calling
 455  * g_print() in the invoking process.
 456  *
 457  * Since: 2.28
 458  **/
 459 void
 460 g_application_command_line_print (GApplicationCommandLine *cmdline,
 461                                   const gchar             *format,
 462                                   ...)
 463 {
 464   gchar *message;
 465   va_list ap;
 466
 467   g_return_if_fail (G_IS_APPLICATION_COMMAND_LINE (cmdline));
 468   g_return_if_fail (format != NULL);
 469
 470   va_start (ap, format);
 471   message = g_strdup_vprintf (format, ap);
 472   va_end (ap);
 473
 474   G_APPLICATION_COMMAND_LINE_GET_CLASS (cmdline)
 475     ->print_literal (cmdline, message);
 476   g_free (message);
 477 }
 478
 479 /**
 480  * g_application_command_line_printerr:
 481  * @cmdline: a #GApplicationCommandLine
 482  * @format: a printf-style format string
 483  * @...: arguments, as per @format
 484  *
 485  * Formats a message and prints it using the stderr print handler in the
 486  * invoking process.
 487  *
 488  * If @cmdline is a local invocation then this is exactly equivalent to
 489  * g_printerr().  If @cmdline is remote then this is equivalent to
 490  * calling g_printerr() in the invoking process.
 491  *
 492  * Since: 2.28
 493  **/
 494 void
 495 g_application_command_line_printerr (GApplicationCommandLine *cmdline,
 496                                      const gchar             *format,
 497                                      ...)
 498 {
 499   gchar *message;
 500   va_list ap;
 501
 502   g_return_if_fail (G_IS_APPLICATION_COMMAND_LINE (cmdline));
 503   g_return_if_fail (format != NULL);
 504
 505   va_start (ap, format);
 506   message = g_strdup_vprintf (format, ap);
 507   va_end (ap);
 508
 509   G_APPLICATION_COMMAND_LINE_GET_CLASS (cmdline)
 510     ->printerr_literal (cmdline, message);
 511   g_free (message);
 512 }
 513
 514 /**
 515  * g_application_command_line_set_exit_status:
 516  * @cmdline: a #GApplicationCommandLine
 517  * @exit_status: the exit status
 518  *
 519  * Sets the exit status that will be used when the invoking process
 520  * exits.
 521  *
 522  * The return value of the #GApplication::command-line signal is
 523  * passed to this function when the handler returns.  This is the usual
 524  * way of setting the exit status.
 525  *
 526  * In the event that you want the remote invocation to continue running
 527  * and want to decide on the exit status in the future, you can use this
 528  * call.  For the case of a remote invocation, the remote process will
 529  * typically exit when the last reference is dropped on @cmdline.  The
 530  * exit status of the remote process will be equal to the last value
 531  * that was set with this function.
 532  *
 533  * In the case that the commandline invocation is local, the situation
 534  * is slightly more complicated.  If the commandline invocation results
 535  * in the mainloop running (ie: because the use-count of the application
 536  * increased to a non-zero value) then the application is considered to
 537  * have been 'successful' in a certain sense, and the exit status is
 538  * always zero.  If the application use count is zero, though, the exit
 539  * status of the local #GApplicationCommandLine is used.
 540  *
 541  * Since: 2.28
 542  **/
 543 void
 544 g_application_command_line_set_exit_status (GApplicationCommandLine *cmdline,
 545                                             int                      exit_status)
 546 {
 547   g_return_if_fail (G_IS_APPLICATION_COMMAND_LINE (cmdline));
 548
 549   cmdline->priv->exit_status = exit_status;
 550 }
 551
 552 /**
 553  * g_application_command_line_get_exit_status:
 554  * @cmdline: a #GApplicationCommandLine
 555  *
 556  * Gets the exit status of @cmdline.  See
 557  * g_application_command_line_set_exit_status() for more information.
 558  *
 559  * Returns: the exit status
 560  *
 561  * Since: 2.28
 562  **/
 563 int
 564 g_application_command_line_get_exit_status (GApplicationCommandLine *cmdline)
 565 {
 566   g_return_val_if_fail (G_IS_APPLICATION_COMMAND_LINE (cmdline), -1);
 567
 568   return cmdline->priv->exit_status;
 569 }
 570
 571 /**
 572  * g_application_command_line_get_platform_data:
 573  * @cmdline: #GApplicationCommandLine
 574  *
 575  * Gets the platform data associated with the invocation of @cmdline.
 576  *
 577  * This is a #GVariant dictionary containing information about the
 578  * context in which the invocation occurred.  It typically contains
 579  * information like the current working directory and the startup
 580  * notification ID.
 581  *
 582  * For local invocation, it will be %NULL.
 583  *
 584  * Returns: the platform data, or %NULL
 585  *
 586  * Since: 2.28
 587  **/
 588 GVariant *
 589 g_application_command_line_get_platform_data (GApplicationCommandLine *cmdline)
 590 {
 591   g_return_val_if_fail (G_IS_APPLICATION_COMMAND_LINE (cmdline), NULL);
 592
 593   if (cmdline->priv->platform_data)
 594     return g_variant_ref (cmdline->priv->platform_data);
 595   else
 596       return NULL;
 597 }