* Boston, MA 02111-1307, USA.
*/
-#include <config.h>
+#include "config.h"
-#include "glib.h"
#include <sys/time.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <fcntl.h>
#include <signal.h>
#include <string.h>
+#include <stdlib.h> /* for fdwalk */
+#include <dirent.h>
#ifdef HAVE_SYS_SELECT_H
#include <sys/select.h>
#endif /* HAVE_SYS_SELECT_H */
+#ifdef HAVE_SYS_RESOURCE_H
+#include <sys/resource.h>
+#endif /* HAVE_SYS_RESOURCE_H */
+
+#include "gspawn.h"
+#include "gthread.h"
+#include "glib/gstdio.h"
+
+#include "genviron.h"
+#include "gmem.h"
+#include "gshell.h"
+#include "gstring.h"
+#include "gstrfuncs.h"
+#include "gtestutils.h"
+#include "gutils.h"
#include "glibintl.h"
+#include "glib-unix.h"
+
+/**
+ * SECTION:spawn
+ * @Short_description: process launching
+ * @Title: Spawning Processes
+ *
+ * GLib supports spawning of processes with an API that is more
+ * convenient than the bare UNIX fork() and exec().
+ *
+ * The g_spawn family of functions has synchronous (g_spawn_sync())
+ * and asynchronous variants (g_spawn_async(), g_spawn_async_with_pipes()),
+ * as well as convenience variants that take a complete shell-like
+ * commandline (g_spawn_command_line_sync(), g_spawn_command_line_async()).
+ *
+ * See #GSubprocess in GIO for a higher-level API that provides
+ * stream interfaces for communication with child processes.
+ */
+
+
static gint g_execute (const gchar *file,
gchar **argv,
gchar **envp,
- gboolean search_path);
+ gboolean search_path,
+ gboolean search_path_from_envp);
-static gboolean make_pipe (gint p[2],
- GError **error);
static gboolean fork_exec_with_pipes (gboolean intermediate_child,
const gchar *working_directory,
gchar **argv,
gchar **envp,
gboolean close_descriptors,
gboolean search_path,
+ gboolean search_path_from_envp,
gboolean stdout_to_null,
gboolean stderr_to_null,
gboolean child_inherits_stdin,
gboolean file_and_argv_zero,
+ gboolean cloexec_pipes,
GSpawnChildSetupFunc child_setup,
gpointer user_data,
- gint *child_pid,
+ GPid *child_pid,
gint *standard_input,
gint *standard_output,
gint *standard_error,
GError **error);
-GQuark
-g_spawn_error_quark (void)
-{
- static GQuark quark = 0;
- if (quark == 0)
- quark = g_quark_from_static_string ("g-exec-error-quark");
- return quark;
-}
+G_DEFINE_QUARK (g-exec-error-quark, g_spawn_error)
+G_DEFINE_QUARK (g-spawn-exit-error-quark, g_spawn_exit_error)
/**
* g_spawn_async:
- * @working_directory: child's current working directory, or %NULL to inherit parent's
- * @argv: child's argument vector
- * @envp: child's environment, or %NULL to inherit parent's
+ * @working_directory: (allow-none): child's current working directory, or %NULL to inherit parent's
+ * @argv: (array zero-terminated=1): child's argument vector
+ * @envp: (array zero-terminated=1) (allow-none): child's environment, or %NULL to inherit parent's
* @flags: flags from #GSpawnFlags
- * @child_setup: function to run in the child just before <function>exec()</function>
- * @user_data: user data for @child_setup
- * @child_pid: return location for child process ID, or %NULL
+ * @child_setup: (scope async) (allow-none): function to run in the child just before exec()
+ * @user_data: (closure): user data for @child_setup
+ * @child_pid: (out) (allow-none): return location for child process reference, or %NULL
* @error: return location for error
*
* See g_spawn_async_with_pipes() for a full description; this function
* simply calls the g_spawn_async_with_pipes() without any pipes.
+ *
+ * You should call g_spawn_close_pid() on the returned child process
+ * reference when you don't need it any more.
*
- * Return value: %TRUE on success, %FALSE if error is set
+ * If you are writing a GTK+ application, and the program you are
+ * spawning is a graphical application, too, then you may want to
+ * use gdk_spawn_on_screen() instead to ensure that the spawned program
+ * opens its windows on the right screen.
+ *
+ * Note that the returned @child_pid on Windows is a handle to the child
+ * process and not its identifier. Process handles and process identifiers
+ * are different concepts on Windows.
+ *
+ * Returns: %TRUE on success, %FALSE if error is set
**/
gboolean
g_spawn_async (const gchar *working_directory,
GSpawnFlags flags,
GSpawnChildSetupFunc child_setup,
gpointer user_data,
- gint *child_pid,
+ GPid *child_pid,
GError **error)
{
g_return_val_if_fail (argv != NULL, FALSE);
* on a file descriptor twice, and another thread has
* re-opened it since the first close)
*/
-static gint
+static void
close_and_invalidate (gint *fd)
{
- gint ret;
-
if (*fd < 0)
- return -1;
+ return;
else
{
- ret = close (*fd);
+ (void) g_close (*fd, NULL);
*fd = -1;
}
-
- return ret;
}
+/* Some versions of OS X define READ_OK in public headers */
+#undef READ_OK
+
typedef enum
{
READ_FAILED = 0, /* FALSE */
gint fd,
GError **error)
{
- gssize bytes;
- gchar buf[4096];
+ gssize bytes;
+ gchar buf[4096];
again:
-
- bytes = read (fd, &buf, 4096);
+ bytes = read (fd, buf, 4096);
if (bytes == 0)
return READ_EOF;
g_string_append_len (str, buf, bytes);
return READ_OK;
}
- else if (bytes < 0 && errno == EINTR)
+ else if (errno == EINTR)
goto again;
- else if (bytes < 0)
+ else
{
+ int errsv = errno;
+
g_set_error (error,
G_SPAWN_ERROR,
G_SPAWN_ERROR_READ,
_("Failed to read data from child process (%s)"),
- g_strerror (errno));
-
+ g_strerror (errsv));
+
return READ_FAILED;
}
- else
- return READ_OK;
}
/**
* g_spawn_sync:
- * @working_directory: child's current working directory, or %NULL to inherit parent's
- * @argv: child's argument vector
- * @envp: child's environment, or %NULL to inherit parent's
+ * @working_directory: (allow-none): child's current working directory, or %NULL to inherit parent's
+ * @argv: (array zero-terminated=1): child's argument vector
+ * @envp: (array zero-terminated=1) (allow-none): child's environment, or %NULL to inherit parent's
* @flags: flags from #GSpawnFlags
- * @child_setup: function to run in the child just before <function>exec()</function>
- * @user_data: user data for @child_setup
- * @standard_output: return location for child output
- * @standard_error: return location for child error messages
- * @exit_status: child exit status, as returned by <function>waitpid()</function>
- * @error: return location for error
+ * @child_setup: (scope async) (allow-none): function to run in the child just before exec()
+ * @user_data: (closure): user data for @child_setup
+ * @standard_output: (out) (array zero-terminated=1) (element-type guint8) (allow-none): return location for child output, or %NULL
+ * @standard_error: (out) (array zero-terminated=1) (element-type guint8) (allow-none): return location for child error messages, or %NULL
+ * @exit_status: (out) (allow-none): return location for child exit status, as returned by waitpid(), or %NULL
+ * @error: return location for error, or %NULL
*
* Executes a child synchronously (waits for the child to exit before returning).
* All output from the child is stored in @standard_output and @standard_error,
- * if those parameters are non-%NULL. If @exit_status is non-%NULL, the exit
- * status of the child is stored there as it would be returned by
- * <function>waitpid()</function>; standard UNIX macros such as
- * <function>WIFEXITED()</function> and <function>WEXITSTATUS()</function>
- * must be used to evaluate the exit status. If an error occurs, no data is
- * returned in @standard_output, @standard_error, or @exit_status.
- *
- * This function calls g_spawn_async_with_pipes() internally; see that function
- * for full details on the other parameters.
+ * if those parameters are non-%NULL. Note that you must set the
+ * %G_SPAWN_STDOUT_TO_DEV_NULL and %G_SPAWN_STDERR_TO_DEV_NULL flags when
+ * passing %NULL for @standard_output and @standard_error.
+ *
+ * If @exit_status is non-%NULL, the platform-specific exit status of
+ * the child is stored there; see the documentation of
+ * g_spawn_check_exit_status() for how to use and interpret this.
+ * Note that it is invalid to pass %G_SPAWN_DO_NOT_REAP_CHILD in
+ * @flags.
+ *
+ * If an error occurs, no data is returned in @standard_output,
+ * @standard_error, or @exit_status.
+ *
+ * This function calls g_spawn_async_with_pipes() internally; see that
+ * function for full details on the other parameters and details on
+ * how these functions work on Windows.
*
- * Return value: %TRUE on success, %FALSE if an error was set.
- **/
+ * Returns: %TRUE on success, %FALSE if an error was set
+ */
gboolean
g_spawn_sync (const gchar *working_directory,
gchar **argv,
{
gint outpipe = -1;
gint errpipe = -1;
- gint pid;
+ GPid pid;
fd_set fds;
gint ret;
GString *outstr = NULL;
envp,
!(flags & G_SPAWN_LEAVE_DESCRIPTORS_OPEN),
(flags & G_SPAWN_SEARCH_PATH) != 0,
+ (flags & G_SPAWN_SEARCH_PATH_FROM_ENVP) != 0,
(flags & G_SPAWN_STDOUT_TO_DEV_NULL) != 0,
(flags & G_SPAWN_STDERR_TO_DEV_NULL) != 0,
(flags & G_SPAWN_CHILD_INHERITS_STDIN) != 0,
(flags & G_SPAWN_FILE_AND_ARGV_ZERO) != 0,
+ (flags & G_SPAWN_CLOEXEC_PIPES) != 0,
child_setup,
user_data,
&pid,
if (outpipe >= 0)
{
- outstr = g_string_new ("");
+ outstr = g_string_new (NULL);
}
if (errpipe >= 0)
{
- errstr = g_string_new ("");
+ errstr = g_string_new (NULL);
}
/* Read data until we get EOF on both pipes. */
NULL, NULL,
NULL /* no timeout */);
- if (ret < 0 && errno != EINTR)
+ if (ret < 0)
{
+ int errsv = errno;
+
+ if (errno == EINTR)
+ continue;
+
failed = TRUE;
g_set_error (error,
G_SPAWN_ERROR,
G_SPAWN_ERROR_READ,
_("Unexpected error in select() reading data from a child process (%s)"),
- g_strerror (errno));
+ g_strerror (errsv));
break;
}
{
if (exit_status)
{
- g_warning ("In call to g_spawn_sync(), exit status of a child process was requested but SIGCHLD action was set to SIG_IGN and ECHILD was received by waitpid(), so exit status can't be returned. This is a bug in the program calling g_spawn_sync(); either don't request the exit status, or don't set the SIGCHLD action.");
+ g_warning ("In call to g_spawn_sync(), exit status of a child process was requested but ECHILD was received by waitpid(). Most likely the process is ignoring SIGCHLD, or some other thread is invoking waitpid() with a nonpositive first argument; either behavior can break applications that use g_spawn_sync either directly or indirectly.");
}
else
{
{
if (!failed) /* avoid error pileups */
{
+ int errsv = errno;
+
failed = TRUE;
g_set_error (error,
G_SPAWN_ERROR,
G_SPAWN_ERROR_READ,
_("Unexpected error in waitpid() (%s)"),
- g_strerror (errno));
+ g_strerror (errsv));
}
}
}
/**
* g_spawn_async_with_pipes:
- * @working_directory: child's current working directory, or %NULL to inherit parent's
- * @argv: child's argument vector
- * @envp: child's environment, or %NULL to inherit parent's
+ * @working_directory: (allow-none): child's current working directory, or %NULL to inherit parent's, in the GLib file name encoding
+ * @argv: (array zero-terminated=1): child's argument vector, in the GLib file name encoding
+ * @envp: (array zero-terminated=1) (allow-none): child's environment, or %NULL to inherit parent's, in the GLib file name encoding
* @flags: flags from #GSpawnFlags
- * @child_setup: function to run in the child just before <function>exec()</function>
- * @user_data: user data for @child_setup
- * @child_pid: return location for child process ID, or %NULL
- * @standard_input: return location for file descriptor to write to child's stdin, or %NULL
- * @standard_output: return location for file descriptor to read child's stdout, or %NULL
- * @standard_error: return location for file descriptor to read child's stderr, or %NULL
+ * @child_setup: (scope async) (allow-none): function to run in the child just before exec()
+ * @user_data: (closure): user data for @child_setup
+ * @child_pid: (out) (allow-none): return location for child process ID, or %NULL
+ * @standard_input: (out) (allow-none): return location for file descriptor to write to child's stdin, or %NULL
+ * @standard_output: (out) (allow-none): return location for file descriptor to read child's stdout, or %NULL
+ * @standard_error: (out) (allow-none): return location for file descriptor to read child's stderr, or %NULL
* @error: return location for error
*
* Executes a child program asynchronously (your program will not
* block waiting for the child to exit). The child program is
- * specified by the only argument that must be provided, @argv. @argv
- * should be a %NULL-terminated array of strings, to be passed as the
- * argument vector for the child. The first string in @argv is of
- * course the name of the program to execute. By default, the name of
- * the program must be a full path; the <envar>PATH</envar> shell variable
- * will only be searched if you pass the %G_SPAWN_SEARCH_PATH flag.
+ * specified by the only argument that must be provided, @argv.
+ * @argv should be a %NULL-terminated array of strings, to be passed
+ * as the argument vector for the child. The first string in @argv
+ * is of course the name of the program to execute. By default, the
+ * name of the program must be a full path. If @flags contains the
+ * %G_SPAWN_SEARCH_PATH flag, the `PATH` environment variable is
+ * used to search for the executable. If @flags contains the
+ * %G_SPAWN_SEARCH_PATH_FROM_ENVP flag, the `PATH` variable from
+ * @envp is used to search for the executable. If both the
+ * %G_SPAWN_SEARCH_PATH and %G_SPAWN_SEARCH_PATH_FROM_ENVP flags
+ * are set, the `PATH` variable from @envp takes precedence over
+ * the environment variable.
+ *
+ * If the program name is not a full path and %G_SPAWN_SEARCH_PATH flag is not
+ * used, then the program will be run from the current directory (or
+ * @working_directory, if specified); this might be unexpected or even
+ * dangerous in some cases when the current directory is world-writable.
+ *
+ * On Windows, note that all the string or string vector arguments to
+ * this function and the other g_spawn*() functions are in UTF-8, the
+ * GLib file name encoding. Unicode characters that are not part of
+ * the system codepage passed in these arguments will be correctly
+ * available in the spawned program only if it uses wide character API
+ * to retrieve its command line. For C programs built with Microsoft's
+ * tools it is enough to make the program have a wmain() instead of
+ * main(). wmain() has a wide character argument vector as parameter.
+ *
+ * At least currently, mingw doesn't support wmain(), so if you use
+ * mingw to develop the spawned program, it will have to call the
+ * undocumented function __wgetmainargs() to get the wide character
+ * argument vector and environment. See gspawn-win32-helper.c in the
+ * GLib sources or init.c in the mingw runtime sources for a prototype
+ * for that function. Alternatively, you can retrieve the Win32 system
+ * level wide character command line passed to the spawned program
+ * using the GetCommandLineW() function.
+ *
+ * On Windows the low-level child process creation API CreateProcess()
+ * doesn't use argument vectors, but a command line. The C runtime
+ * library's spawn*() family of functions (which g_spawn_async_with_pipes()
+ * eventually calls) paste the argument vector elements together into
+ * a command line, and the C runtime startup code does a corresponding
+ * reconstruction of an argument vector from the command line, to be
+ * passed to main(). Complications arise when you have argument vector
+ * elements that contain spaces of double quotes. The spawn*() functions
+ * don't do any quoting or escaping, but on the other hand the startup
+ * code does do unquoting and unescaping in order to enable receiving
+ * arguments with embedded spaces or double quotes. To work around this
+ * asymmetry, g_spawn_async_with_pipes() will do quoting and escaping on
+ * argument vector elements that need it before calling the C runtime
+ * spawn() function.
+ *
+ * The returned @child_pid on Windows is a handle to the child
+ * process, not its identifier. Process handles and process
+ * identifiers are different concepts on Windows.
*
* @envp is a %NULL-terminated array of strings, where each string
- * has the form <literal>KEY=VALUE</literal>. This will become
- * the child's environment. If @envp is %NULL, the child inherits its
- * parent's environment.
+ * has the form `KEY=VALUE`. This will become the child's environment.
+ * If @envp is %NULL, the child inherits its parent's environment.
*
* @flags should be the bitwise OR of any flags you want to affect the
- * function's behavior. The %G_SPAWN_DO_NOT_REAP_CHILD means that the
- * child will not be automatically reaped; you must call
- * <function>waitpid()</function> or handle %SIGCHLD yourself, or the
- * child will become a zombie.
+ * function's behaviour. The %G_SPAWN_DO_NOT_REAP_CHILD means that the
+ * child will not automatically be reaped; you must use a child watch to
+ * be notified about the death of the child process. Eventually you must
+ * call g_spawn_close_pid() on the @child_pid, in order to free
+ * resources which may be associated with the child process. (On Unix,
+ * using a child watch is equivalent to calling waitpid() or handling
+ * the %SIGCHLD signal manually. On Windows, calling g_spawn_close_pid()
+ * is equivalent to calling CloseHandle() on the process handle returned
+ * in @child_pid). See g_child_watch_add().
+ *
* %G_SPAWN_LEAVE_DESCRIPTORS_OPEN means that the parent's open file
- * descriptors will be inherited by the child; otherwise all
- * descriptors except stdin/stdout/stderr will be closed before
- * calling <function>exec()</function> in the child. %G_SPAWN_SEARCH_PATH
- * means that <literal>argv[0]</literal> need not be an absolute path, it
- * will be looked for in the user's <envar>PATH</envar>.
- * %G_SPAWN_STDOUT_TO_DEV_NULL means that the child's standad output will
- * be discarded, instead of going to the same location as the parent's
- * standard output.
+ * descriptors will be inherited by the child; otherwise all descriptors
+ * except stdin/stdout/stderr will be closed before calling exec() in
+ * the child. %G_SPAWN_SEARCH_PATH means that @argv[0] need not be an
+ * absolute path, it will be looked for in the `PATH` environment
+ * variable. %G_SPAWN_SEARCH_PATH_FROM_ENVP means need not be an
+ * absolute path, it will be looked for in the `PATH` variable from
+ * @envp. If both %G_SPAWN_SEARCH_PATH and %G_SPAWN_SEARCH_PATH_FROM_ENVP
+ * are used, the value from @envp takes precedence over the environment.
+ * %G_SPAWN_STDOUT_TO_DEV_NULL means that the child's standard output
+ * will be discarded, instead of going to the same location as the parent's
+ * standard output. If you use this flag, @standard_output must be %NULL.
* %G_SPAWN_STDERR_TO_DEV_NULL means that the child's standard error
- * will be discarded. %G_SPAWN_CHILD_INHERITS_STDIN means that
- * the child will inherit the parent's standard input (by default,
- * the child's standard input is attached to /dev/null).
+ * will be discarded, instead of going to the same location as the parent's
+ * standard error. If you use this flag, @standard_error must be %NULL.
+ * %G_SPAWN_CHILD_INHERITS_STDIN means that the child will inherit the parent's
+ * standard input (by default, the child's standard input is attached to
+ * /dev/null). If you use this flag, @standard_input must be %NULL.
* %G_SPAWN_FILE_AND_ARGV_ZERO means that the first element of @argv is
- * the file to execute, while the remaining elements are the
- * actual argument vector to pass to the file. Normally
- * g_spawn_async_with_pipes() uses @argv[0] as the file to execute, and
- * passes all of @argv to the child.
+ * the file to execute, while the remaining elements are the actual
+ * argument vector to pass to the file. Normally g_spawn_async_with_pipes()
+ * uses @argv[0] as the file to execute, and passes all of @argv to the child.
*
- * @child_setup and @user_data are a function and user data to be
- * called in the child after GLib has performed all the setup it plans
- * to perform (including creating pipes, closing file descriptors,
- * etc.) but before calling <function>exec()</function>. That is,
- * @child_setup is called just before calling <function>exec()</function>
- * in the child. Obviously actions taken in this function will only affect
- * the child, not the parent.
+ * @child_setup and @user_data are a function and user data. On POSIX
+ * platforms, the function is called in the child after GLib has
+ * performed all the setup it plans to perform (including creating
+ * pipes, closing file descriptors, etc.) but before calling exec().
+ * That is, @child_setup is called just before calling exec() in the
+ * child. Obviously actions taken in this function will only affect
+ * the child, not the parent.
*
- * If non-%NULL, @child_pid will be filled with the child's process
- * ID. You can use the process ID to send signals to the child, or
- * to <function>waitpid()</function> if you specified the
- * %G_SPAWN_DO_NOT_REAP_CHILD flag.
+ * On Windows, there is no separate fork() and exec() functionality.
+ * Child processes are created and run with a single API call,
+ * CreateProcess(). There is no sensible thing @child_setup
+ * could be used for on Windows so it is ignored and not called.
+ *
+ * If non-%NULL, @child_pid will on Unix be filled with the child's
+ * process ID. You can use the process ID to send signals to the child,
+ * or to use g_child_watch_add() (or waitpid()) if you specified the
+ * %G_SPAWN_DO_NOT_REAP_CHILD flag. On Windows, @child_pid will be
+ * filled with a handle to the child process only if you specified the
+ * %G_SPAWN_DO_NOT_REAP_CHILD flag. You can then access the child
+ * process using the Win32 API, for example wait for its termination
+ * with the WaitFor*() functions, or examine its exit code with
+ * GetExitCodeProcess(). You should close the handle with CloseHandle()
+ * or g_spawn_close_pid() when you no longer need it.
*
* If non-%NULL, the @standard_input, @standard_output, @standard_error
* locations will be filled with file descriptors for writing to the child's
* when they are no longer in use. If these parameters are %NULL, the
* corresponding pipe won't be created.
*
+ * If @standard_input is NULL, the child's standard input is attached to
+ * /dev/null unless %G_SPAWN_CHILD_INHERITS_STDIN is set.
+ *
+ * If @standard_error is NULL, the child's standard error goes to the same
+ * location as the parent's standard error unless %G_SPAWN_STDERR_TO_DEV_NULL
+ * is set.
+ *
+ * If @standard_output is NULL, the child's standard output goes to the same
+ * location as the parent's standard output unless %G_SPAWN_STDOUT_TO_DEV_NULL
+ * is set.
+ *
* @error can be %NULL to ignore errors, or non-%NULL to report errors.
- * If an error is set, the function returns %FALSE. Errors
- * are reported even if they occur in the child (for example if the
- * executable in <literal>argv[0]</literal> is not found). Typically
- * the <literal>message</literal> field of returned errors should be displayed
- * to users. Possible errors are those from the #G_SPAWN_ERROR domain.
+ * If an error is set, the function returns %FALSE. Errors are reported
+ * even if they occur in the child (for example if the executable in
+ * @argv[0] is not found). Typically the `message` field of returned
+ * errors should be displayed to users. Possible errors are those from
+ * the #G_SPAWN_ERROR domain.
*
* If an error occurs, @child_pid, @standard_input, @standard_output,
* and @standard_error will not be filled with valid values.
+ *
+ * If @child_pid is not %NULL and an error does not occur then the returned
+ * process reference must be closed using g_spawn_close_pid().
+ *
+ * If you are writing a GTK+ application, and the program you
+ * are spawning is a graphical application, too, then you may
+ * want to use gdk_spawn_on_screen_with_pipes() instead to ensure that
+ * the spawned program opens its windows on the right screen.
*
- * Return value: %TRUE on success, %FALSE if an error was set
- **/
+ * Returns: %TRUE on success, %FALSE if an error was set
+ */
gboolean
g_spawn_async_with_pipes (const gchar *working_directory,
gchar **argv,
GSpawnFlags flags,
GSpawnChildSetupFunc child_setup,
gpointer user_data,
- gint *child_pid,
+ GPid *child_pid,
gint *standard_input,
gint *standard_output,
gint *standard_error,
envp,
!(flags & G_SPAWN_LEAVE_DESCRIPTORS_OPEN),
(flags & G_SPAWN_SEARCH_PATH) != 0,
+ (flags & G_SPAWN_SEARCH_PATH_FROM_ENVP) != 0,
(flags & G_SPAWN_STDOUT_TO_DEV_NULL) != 0,
(flags & G_SPAWN_STDERR_TO_DEV_NULL) != 0,
(flags & G_SPAWN_CHILD_INHERITS_STDIN) != 0,
(flags & G_SPAWN_FILE_AND_ARGV_ZERO) != 0,
+ (flags & G_SPAWN_CLOEXEC_PIPES) != 0,
child_setup,
user_data,
child_pid,
/**
* g_spawn_command_line_sync:
* @command_line: a command line
- * @standard_output: return location for child output
- * @standard_error: return location for child errors
- * @exit_status: return location for child exit status
+ * @standard_output: (out) (array zero-terminated=1) (element-type guint8) (allow-none): return location for child output
+ * @standard_error: (out) (array zero-terminated=1) (element-type guint8) (allow-none): return location for child errors
+ * @exit_status: (out) (allow-none): return location for child exit status, as returned by waitpid()
* @error: return location for errors
*
* A simple version of g_spawn_sync() with little-used parameters
* implications, so consider using g_spawn_sync() directly if
* appropriate. Possible errors are those from g_spawn_sync() and those
* from g_shell_parse_argv().
+ *
+ * If @exit_status is non-%NULL, the platform-specific exit status of
+ * the child is stored there; see the documentation of
+ * g_spawn_check_exit_status() for how to use and interpret this.
*
* On Windows, please note the implications of g_shell_parse_argv()
- * parsing @command_line. Space is a separator, and backslashes are
- * special. Thus you cannot simply pass a @command_line consisting of
- * a canonical Windows path, like "c:\\program files\\app\\app.exe",
- * as the backslashes will be eaten, and the space will act as a
- * separator. You need to enclose the path with single quotes, like
- * "'c:\\program files\\app\\app.exe'".
+ * parsing @command_line. Parsing is done according to Unix shell rules, not
+ * Windows command interpreter rules.
+ * Space is a separator, and backslashes are
+ * special. Thus you cannot simply pass a @command_line containing
+ * canonical Windows paths, like "c:\\program files\\app\\app.exe", as
+ * the backslashes will be eaten, and the space will act as a
+ * separator. You need to enclose such paths with single quotes, like
+ * "'c:\\program files\\app\\app.exe' 'e:\\folder\\argument.txt'".
*
- * Return value: %TRUE on success, %FALSE if an error was set
+ * Returns: %TRUE on success, %FALSE if an error was set
**/
gboolean
g_spawn_command_line_sync (const gchar *command_line,
GError **error)
{
gboolean retval;
- gchar **argv = 0;
+ gchar **argv = NULL;
g_return_val_if_fail (command_line != NULL, FALSE);
*
* The same concerns on Windows apply as for g_spawn_command_line_sync().
*
- * Return value: %TRUE on success, %FALSE if error is set.
+ * Returns: %TRUE on success, %FALSE if error is set
**/
gboolean
g_spawn_command_line_async (const gchar *command_line,
GError **error)
{
gboolean retval;
- gchar **argv = 0;
+ gchar **argv = NULL;
g_return_val_if_fail (command_line != NULL, FALSE);
return retval;
}
+/**
+ * g_spawn_check_exit_status:
+ * @exit_status: An exit code as returned from g_spawn_sync()
+ * @error: a #GError
+ *
+ * Set @error if @exit_status indicates the child exited abnormally
+ * (e.g. with a nonzero exit code, or via a fatal signal).
+ *
+ * The g_spawn_sync() and g_child_watch_add() family of APIs return an
+ * exit status for subprocesses encoded in a platform-specific way.
+ * On Unix, this is guaranteed to be in the same format waitpid() returns,
+ * and on Windows it is guaranteed to be the result of GetExitCodeProcess().
+ *
+ * Prior to the introduction of this function in GLib 2.34, interpreting
+ * @exit_status required use of platform-specific APIs, which is problematic
+ * for software using GLib as a cross-platform layer.
+ *
+ * Additionally, many programs simply want to determine whether or not
+ * the child exited successfully, and either propagate a #GError or
+ * print a message to standard error. In that common case, this function
+ * can be used. Note that the error message in @error will contain
+ * human-readable information about the exit status.
+ *
+ * The @domain and @code of @error have special semantics in the case
+ * where the process has an "exit code", as opposed to being killed by
+ * a signal. On Unix, this happens if WIFEXITED() would be true of
+ * @exit_status. On Windows, it is always the case.
+ *
+ * The special semantics are that the actual exit code will be the
+ * code set in @error, and the domain will be %G_SPAWN_EXIT_ERROR.
+ * This allows you to differentiate between different exit codes.
+ *
+ * If the process was terminated by some means other than an exit
+ * status, the domain will be %G_SPAWN_ERROR, and the code will be
+ * %G_SPAWN_ERROR_FAILED.
+ *
+ * This function just offers convenience; you can of course also check
+ * the available platform via a macro such as %G_OS_UNIX, and use
+ * WIFEXITED() and WEXITSTATUS() on @exit_status directly. Do not attempt
+ * to scan or parse the error message string; it may be translated and/or
+ * change in future versions of GLib.
+ *
+ * Returns: %TRUE if child exited successfully, %FALSE otherwise (and
+ * @error will be set)
+ *
+ * Since: 2.34
+ */
+gboolean
+g_spawn_check_exit_status (gint exit_status,
+ GError **error)
+{
+ gboolean ret = FALSE;
+
+ if (WIFEXITED (exit_status))
+ {
+ if (WEXITSTATUS (exit_status) != 0)
+ {
+ g_set_error (error, G_SPAWN_EXIT_ERROR, WEXITSTATUS (exit_status),
+ _("Child process exited with code %ld"),
+ (long) WEXITSTATUS (exit_status));
+ goto out;
+ }
+ }
+ else if (WIFSIGNALED (exit_status))
+ {
+ g_set_error (error, G_SPAWN_ERROR, G_SPAWN_ERROR_FAILED,
+ _("Child process killed by signal %ld"),
+ (long) WTERMSIG (exit_status));
+ goto out;
+ }
+ else if (WIFSTOPPED (exit_status))
+ {
+ g_set_error (error, G_SPAWN_ERROR, G_SPAWN_ERROR_FAILED,
+ _("Child process stopped by signal %ld"),
+ (long) WSTOPSIG (exit_status));
+ goto out;
+ }
+ else
+ {
+ g_set_error (error, G_SPAWN_ERROR, G_SPAWN_ERROR_FAILED,
+ _("Child process exited abnormally"));
+ goto out;
+ }
+
+ ret = TRUE;
+ out:
+ return ret;
+}
+
static gint
exec_err_to_g_error (gint en)
{
#ifdef E2BIG
case E2BIG:
- return G_SPAWN_ERROR_2BIG;
+ return G_SPAWN_ERROR_TOO_BIG;
break;
#endif
}
}
+static gssize
+write_all (gint fd, gconstpointer vbuf, gsize to_write)
+{
+ gchar *buf = (gchar *) vbuf;
+
+ while (to_write > 0)
+ {
+ gssize count = write (fd, buf, to_write);
+ if (count < 0)
+ {
+ if (errno != EINTR)
+ return FALSE;
+ }
+ else
+ {
+ to_write -= count;
+ buf += count;
+ }
+ }
+
+ return TRUE;
+}
+
+G_GNUC_NORETURN
static void
write_err_and_exit (gint fd, gint msg)
{
gint en = errno;
- write (fd, &msg, sizeof(msg));
- write (fd, &en, sizeof(en));
+ write_all (fd, &msg, sizeof(msg));
+ write_all (fd, &en, sizeof(en));
_exit (1);
}
-static void
-set_cloexec (gint fd)
+static int
+set_cloexec (void *data, gint fd)
{
- fcntl (fd, F_SETFD, FD_CLOEXEC);
+ if (fd >= GPOINTER_TO_INT (data))
+ fcntl (fd, F_SETFD, FD_CLOEXEC);
+
+ return 0;
}
+#ifndef HAVE_FDWALK
+static int
+fdwalk (int (*cb)(void *data, int fd), void *data)
+{
+ gint open_max;
+ gint fd;
+ gint res = 0;
+
+#ifdef HAVE_SYS_RESOURCE_H
+ struct rlimit rl;
+#endif
+
+#ifdef __linux__
+ DIR *d;
+
+ if ((d = opendir("/proc/self/fd"))) {
+ struct dirent *de;
+
+ while ((de = readdir(d))) {
+ glong l;
+ gchar *e = NULL;
+
+ if (de->d_name[0] == '.')
+ continue;
+
+ errno = 0;
+ l = strtol(de->d_name, &e, 10);
+ if (errno != 0 || !e || *e)
+ continue;
+
+ fd = (gint) l;
+
+ if ((glong) fd != l)
+ continue;
+
+ if (fd == dirfd(d))
+ continue;
+
+ if ((res = cb (data, fd)) != 0)
+ break;
+ }
+
+ closedir(d);
+ return res;
+ }
+
+ /* If /proc is not mounted or not accessible we fall back to the old
+ * rlimit trick */
+
+#endif
+
+#ifdef HAVE_SYS_RESOURCE_H
+
+ if (getrlimit(RLIMIT_NOFILE, &rl) == 0 && rl.rlim_max != RLIM_INFINITY)
+ open_max = rl.rlim_max;
+ else
+#endif
+ open_max = sysconf (_SC_OPEN_MAX);
+
+ for (fd = 0; fd < open_max; fd++)
+ if ((res = cb (data, fd)) != 0)
+ break;
+
+ return res;
+}
+#endif
+
static gint
sane_dup2 (gint fd1, gint fd2)
{
return ret;
}
+static gint
+sane_open (const char *path, gint mode)
+{
+ gint ret;
+
+ retry:
+ ret = open (path, mode);
+ if (ret < 0 && errno == EINTR)
+ goto retry;
+
+ return ret;
+}
+
enum
{
CHILD_CHDIR_FAILED,
gchar **envp,
gboolean close_descriptors,
gboolean search_path,
+ gboolean search_path_from_envp,
gboolean stdout_to_null,
gboolean stderr_to_null,
gboolean child_inherits_stdin,
*/
if (close_descriptors)
{
- gint open_max;
- gint i;
-
- open_max = sysconf (_SC_OPEN_MAX);
- for (i = 3; i < open_max; i++)
- set_cloexec (i);
+ fdwalk (set_cloexec, GINT_TO_POINTER(3));
}
else
{
/* We need to do child_err_report_fd anyway */
- set_cloexec (child_err_report_fd);
+ set_cloexec (GINT_TO_POINTER(0), child_err_report_fd);
}
/* Redirect pipes as required */
{
/* Keep process from blocking on a read of stdin */
gint read_null = open ("/dev/null", O_RDONLY);
+ g_assert (read_null != -1);
sane_dup2 (read_null, 0);
close_and_invalidate (&read_null);
}
}
else if (stdout_to_null)
{
- gint write_null = open ("/dev/null", O_WRONLY);
+ gint write_null = sane_open ("/dev/null", O_WRONLY);
+ g_assert (write_null != -1);
sane_dup2 (write_null, 1);
close_and_invalidate (&write_null);
}
}
else if (stderr_to_null)
{
- gint write_null = open ("/dev/null", O_WRONLY);
+ gint write_null = sane_open ("/dev/null", O_WRONLY);
sane_dup2 (write_null, 2);
close_and_invalidate (&write_null);
}
g_execute (argv[0],
file_and_argv_zero ? argv + 1 : argv,
- envp, search_path);
+ envp, search_path, search_path_from_envp);
/* Exec failed */
write_err_and_exit (child_err_report_fd,
if (chunk < 0)
{
+ int errsv = errno;
+
/* Some weird shit happened, bail out */
-
g_set_error (error,
G_SPAWN_ERROR,
G_SPAWN_ERROR_FAILED,
_("Failed to read from child pipe (%s)"),
- g_strerror (errno));
+ g_strerror (errsv));
return FALSE;
}
gchar **envp,
gboolean close_descriptors,
gboolean search_path,
+ gboolean search_path_from_envp,
gboolean stdout_to_null,
gboolean stderr_to_null,
gboolean child_inherits_stdin,
gboolean file_and_argv_zero,
+ gboolean cloexec_pipes,
GSpawnChildSetupFunc child_setup,
gpointer user_data,
- gint *child_pid,
+ GPid *child_pid,
gint *standard_input,
gint *standard_output,
gint *standard_error,
GError **error)
{
- gint pid;
+ GPid pid = -1;
gint stdin_pipe[2] = { -1, -1 };
gint stdout_pipe[2] = { -1, -1 };
gint stderr_pipe[2] = { -1, -1 };
gint child_err_report_pipe[2] = { -1, -1 };
gint child_pid_report_pipe[2] = { -1, -1 };
+ guint pipe_flags = cloexec_pipes ? FD_CLOEXEC : 0;
gint status;
- if (!make_pipe (child_err_report_pipe, error))
+ if (!g_unix_open_pipe (child_err_report_pipe, pipe_flags, error))
return FALSE;
- if (intermediate_child && !make_pipe (child_pid_report_pipe, error))
+ if (intermediate_child && !g_unix_open_pipe (child_pid_report_pipe, pipe_flags, error))
goto cleanup_and_fail;
- if (standard_input && !make_pipe (stdin_pipe, error))
+ if (standard_input && !g_unix_open_pipe (stdin_pipe, pipe_flags, error))
goto cleanup_and_fail;
- if (standard_output && !make_pipe (stdout_pipe, error))
+ if (standard_output && !g_unix_open_pipe (stdout_pipe, pipe_flags, error))
goto cleanup_and_fail;
- if (standard_error && !make_pipe (stderr_pipe, error))
+ if (standard_error && !g_unix_open_pipe (stderr_pipe, FD_CLOEXEC, error))
goto cleanup_and_fail;
pid = fork ();
if (pid < 0)
- {
+ {
+ int errsv = errno;
+
g_set_error (error,
G_SPAWN_ERROR,
G_SPAWN_ERROR_FORK,
_("Failed to fork (%s)"),
- g_strerror (errno));
+ g_strerror (errsv));
goto cleanup_and_fail;
}
/* Immediate child. This may or may not be the child that
* actually execs the new process.
*/
+
+ /* Reset some signal handlers that we may use */
+ signal (SIGCHLD, SIG_DFL);
+ signal (SIGINT, SIG_DFL);
+ signal (SIGTERM, SIG_DFL);
+ signal (SIGHUP, SIG_DFL);
/* Be sure we crash if the parent exits
* and we write to the err_report_pipe
* is to exit, so we can waitpid() it immediately.
* Then the grandchild will not become a zombie.
*/
- gint grandchild_pid;
+ GPid grandchild_pid;
grandchild_pid = fork ();
if (grandchild_pid < 0)
{
/* report -1 as child PID */
- write (child_pid_report_pipe[1], &grandchild_pid,
- sizeof(grandchild_pid));
+ write_all (child_pid_report_pipe[1], &grandchild_pid,
+ sizeof(grandchild_pid));
write_err_and_exit (child_err_report_pipe[1],
CHILD_FORK_FAILED);
}
else if (grandchild_pid == 0)
{
+ close_and_invalidate (&child_pid_report_pipe[1]);
do_exec (child_err_report_pipe[1],
stdin_pipe[0],
stdout_pipe[1],
envp,
close_descriptors,
search_path,
+ search_path_from_envp,
stdout_to_null,
stderr_to_null,
child_inherits_stdin,
}
else
{
- write (child_pid_report_pipe[1], &grandchild_pid, sizeof(grandchild_pid));
+ write_all (child_pid_report_pipe[1], &grandchild_pid, sizeof(grandchild_pid));
close_and_invalidate (&child_pid_report_pipe[1]);
_exit (0);
envp,
close_descriptors,
search_path,
+ search_path_from_envp,
stdout_to_null,
stderr_to_null,
child_inherits_stdin,
if (n_ints < 1)
{
+ int errsv = errno;
+
g_set_error (error,
G_SPAWN_ERROR,
G_SPAWN_ERROR_FAILED,
_("Failed to read enough data from child pid pipe (%s)"),
- g_strerror (errno));
+ g_strerror (errsv));
goto cleanup_and_fail;
}
else
}
cleanup_and_fail:
+
+ /* There was an error from the Child, reap the child to avoid it being
+ a zombie.
+ */
+
+ if (pid > 0)
+ {
+ wait_failed:
+ if (waitpid (pid, NULL, 0) < 0)
+ {
+ if (errno == EINTR)
+ goto wait_failed;
+ else if (errno == ECHILD)
+ ; /* do nothing, child already reaped */
+ else
+ g_warning ("waitpid() should not fail in "
+ "'fork_exec_with_pipes'");
+ }
+ }
+
close_and_invalidate (&child_err_report_pipe[0]);
close_and_invalidate (&child_err_report_pipe[1]);
close_and_invalidate (&child_pid_report_pipe[0]);
return FALSE;
}
-static gboolean
-make_pipe (gint p[2],
- GError **error)
-{
- if (pipe (p) < 0)
- {
- g_set_error (error,
- G_SPAWN_ERROR,
- G_SPAWN_ERROR_FAILED,
- _("Failed to create pipe for communicating with child process (%s)"),
- g_strerror (errno));
- return FALSE;
- }
- else
- return TRUE;
-}
-
/* Based on execvp from GNU C Library */
static void
script_execute (const gchar *file,
gchar **argv,
- gchar **envp,
- gboolean search_path)
+ gchar **envp)
{
/* Count the arguments. */
int argc = 0;
g_execute (const gchar *file,
gchar **argv,
gchar **envp,
- gboolean search_path)
+ gboolean search_path,
+ gboolean search_path_from_envp)
{
if (*file == '\0')
{
return -1;
}
- if (!search_path || strchr (file, '/') != NULL)
+ if (!(search_path || search_path_from_envp) || strchr (file, '/') != NULL)
{
/* Don't search when it contains a slash. */
if (envp)
execv (file, argv);
if (errno == ENOEXEC)
- script_execute (file, argv, envp, FALSE);
+ script_execute (file, argv, envp);
}
else
{
gboolean got_eacces = 0;
const gchar *path, *p;
gchar *name, *freeme;
- size_t len;
- size_t pathlen;
+ gsize len;
+ gsize pathlen;
+
+ path = NULL;
+ if (search_path_from_envp)
+ path = g_environ_getenv (envp, "PATH");
+ if (search_path && path == NULL)
+ path = g_getenv ("PATH");
- path = g_getenv ("PATH");
if (path == NULL)
{
- /* There is no `PATH' in the environment. The default
+ /* There is no 'PATH' in the environment. The default
* search path in libc is the current directory followed by
- * the path `confstr' returns for `_CS_PATH'.
+ * the path 'confstr' returns for '_CS_PATH'.
*/
/* In GLib we put . last, for security, and don't use the
if (p == path)
/* Two adjacent colons, or a colon at the beginning or the end
- * of `PATH' means to search the current directory.
+ * of 'PATH' means to search the current directory.
*/
startp = name + 1;
else
execv (startp, argv);
if (errno == ENOEXEC)
- script_execute (startp, argv, envp, search_path);
+ script_execute (startp, argv, envp);
switch (errno)
{
case EACCES:
- /* Record the we got a `Permission denied' error. If we end
+ /* Record the we got a 'Permission denied' error. If we end
* up finding no executable we can use, we want to diagnose
* that we did find one but were denied access.
*/
*/
break;
+ case ENODEV:
+ case ETIMEDOUT:
+ /* Some strange filesystems like AFS return even
+ * stranger error numbers. They cannot reasonably mean anything
+ * else so ignore those, too.
+ */
+ break;
+
default:
/* Some other error means we found an executable file, but
* something went wrong executing it; return the error to our
/* Return the error from the last attempt (probably ENOENT). */
return -1;
}
+
+/**
+ * g_spawn_close_pid:
+ * @pid: The process reference to close
+ *
+ * On some platforms, notably Windows, the #GPid type represents a resource
+ * which must be closed to prevent resource leaking. g_spawn_close_pid()
+ * is provided for this purpose. It should be used on all platforms, even
+ * though it doesn't do anything under UNIX.
+ **/
+void
+g_spawn_close_pid (GPid pid)
+{
+}