| /* gspawn.c - Process launching |
| * |
| * Copyright 2000 Red Hat, Inc. |
| * g_execvpe implementation based on GNU libc execvp: |
| * Copyright 1991, 92, 95, 96, 97, 98, 99 Free Software Foundation, Inc. |
| * |
| * GLib is free software; you can redistribute it and/or |
| * modify it under the terms of the GNU Lesser General Public License as |
| * published by the Free Software Foundation; either version 2 of the |
| * License, or (at your option) any later version. |
| * |
| * GLib is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| * Lesser General Public License for more details. |
| * |
| * You should have received a copy of the GNU Lesser General Public |
| * License along with GLib; see the file COPYING.LIB. If not, write |
| * to the Free Software Foundation, Inc., 59 Temple Place - Suite 330, |
| * Boston, MA 02111-1307, USA. |
| */ |
| |
| #include "glib.h" |
| #include <sys/time.h> |
| #include <sys/types.h> |
| #include <sys/wait.h> |
| #include <unistd.h> |
| #include <errno.h> |
| #include <fcntl.h> |
| #include <signal.h> |
| #include <string.h> |
| |
| #ifdef HAVE_SYS_SELECT_H |
| #include <sys/select.h> |
| #endif /* HAVE_SYS_SELECT_H */ |
| |
| #include "glibintl.h" |
| |
| static gint g_execute (const gchar *file, |
| gchar **argv, |
| gchar **envp, |
| gboolean search_path); |
| |
| 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 stdout_to_null, |
| gboolean stderr_to_null, |
| gboolean child_inherits_stdin, |
| GSpawnChildSetupFunc child_setup, |
| gpointer user_data, |
| gint *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_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 |
| * @flags: flags from #GSpawnFlags |
| * @child_setup: function to run in the child just before exec() |
| * @user_data: user data for @child_setup |
| * @child_pid: return location for child process ID, 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. |
| * |
| * Return value: TRUE on success, FALSE if error is set |
| **/ |
| gboolean |
| g_spawn_async (const gchar *working_directory, |
| gchar **argv, |
| gchar **envp, |
| GSpawnFlags flags, |
| GSpawnChildSetupFunc child_setup, |
| gpointer user_data, |
| gint *child_pid, |
| GError **error) |
| { |
| g_return_val_if_fail (argv != NULL, FALSE); |
| |
| return g_spawn_async_with_pipes (working_directory, |
| argv, envp, |
| flags, |
| child_setup, |
| user_data, |
| child_pid, |
| NULL, NULL, NULL, |
| error); |
| } |
| |
| /* Avoids a danger in threaded situations (calling close() |
| * on a file descriptor twice, and another thread has |
| * re-opened it since the first close) |
| */ |
| static gint |
| close_and_invalidate (gint *fd) |
| { |
| gint ret; |
| |
| ret = close (*fd); |
| *fd = -1; |
| |
| return ret; |
| } |
| |
| typedef enum |
| { |
| READ_FAILED = 0, /* FALSE */ |
| READ_OK, |
| READ_EOF |
| } ReadResult; |
| |
| static ReadResult |
| read_data (GString *str, |
| gint fd, |
| GError **error) |
| { |
| gint bytes; |
| gchar buf[4096]; |
| |
| again: |
| |
| bytes = read (fd, &buf, 4096); |
| |
| if (bytes == 0) |
| return READ_EOF; |
| else if (bytes > 0) |
| { |
| g_string_append_len (str, buf, bytes); |
| return READ_OK; |
| } |
| else if (bytes < 0 && errno == EINTR) |
| goto again; |
| else if (bytes < 0) |
| { |
| g_set_error (error, |
| G_SPAWN_ERROR, |
| G_SPAWN_ERROR_READ, |
| _("Failed to read data from child process (%s)"), |
| g_strerror (errno)); |
| |
| 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 |
| * @flags: flags from #GSpawnFlags |
| * @child_setup: function to run in the child just before exec() |
| * @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 waitpid() |
| * @error: return location for error |
| * |
| * 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 by waitpid(); standard UNIX |
| * macros such as WIFEXITED() and WEXITSTATUS() 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. |
| * |
| * Return value: TRUE on success, FALSE if an error was set. |
| **/ |
| gboolean |
| g_spawn_sync (const gchar *working_directory, |
| gchar **argv, |
| gchar **envp, |
| GSpawnFlags flags, |
| GSpawnChildSetupFunc child_setup, |
| gpointer user_data, |
| gchar **standard_output, |
| gchar **standard_error, |
| gint *exit_status, |
| GError **error) |
| { |
| gint outpipe = -1; |
| gint errpipe = -1; |
| gint pid; |
| fd_set fds; |
| gint ret; |
| GString *outstr = NULL; |
| GString *errstr = NULL; |
| gboolean failed; |
| gint status; |
| |
| g_return_val_if_fail (argv != NULL, FALSE); |
| g_return_val_if_fail (!(flags & G_SPAWN_DO_NOT_REAP_CHILD), FALSE); |
| g_return_val_if_fail (standard_output == NULL || |
| !(flags & G_SPAWN_STDOUT_TO_DEV_NULL), FALSE); |
| g_return_val_if_fail (standard_error == NULL || |
| !(flags & G_SPAWN_STDERR_TO_DEV_NULL), FALSE); |
| |
| /* Just to ensure segfaults if callers try to use |
| * these when an error is reported. |
| */ |
| if (standard_output) |
| *standard_output = NULL; |
| |
| if (standard_error) |
| *standard_error = NULL; |
| |
| if (!fork_exec_with_pipes (FALSE, |
| working_directory, |
| argv, |
| envp, |
| !(flags & G_SPAWN_LEAVE_DESCRIPTORS_OPEN), |
| (flags & G_SPAWN_SEARCH_PATH) != 0, |
| (flags & G_SPAWN_STDOUT_TO_DEV_NULL) != 0, |
| (flags & G_SPAWN_STDERR_TO_DEV_NULL) != 0, |
| (flags & G_SPAWN_CHILD_INHERITS_STDIN) != 0, |
| child_setup, |
| user_data, |
| &pid, |
| NULL, |
| standard_output ? &outpipe : NULL, |
| standard_error ? &errpipe : NULL, |
| error)) |
| return FALSE; |
| |
| /* Read data from child. */ |
| |
| failed = FALSE; |
| |
| if (outpipe >= 0) |
| { |
| outstr = g_string_new (""); |
| } |
| |
| if (errpipe >= 0) |
| { |
| errstr = g_string_new (""); |
| } |
| |
| /* Read data until we get EOF on both pipes. */ |
| while (!failed && |
| (outpipe >= 0 || |
| errpipe >= 0)) |
| { |
| ret = 0; |
| |
| FD_ZERO (&fds); |
| if (outpipe >= 0) |
| FD_SET (outpipe, &fds); |
| if (errpipe >= 0) |
| FD_SET (errpipe, &fds); |
| |
| ret = select (MAX (outpipe, errpipe) + 1, |
| &fds, |
| NULL, NULL, |
| NULL /* no timeout */); |
| |
| if (ret < 0 && errno != EINTR) |
| { |
| 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)); |
| |
| break; |
| } |
| |
| if (outpipe >= 0 && FD_ISSET (outpipe, &fds)) |
| { |
| switch (read_data (outstr, outpipe, error)) |
| { |
| case READ_FAILED: |
| failed = TRUE; |
| break; |
| case READ_EOF: |
| close_and_invalidate (&outpipe); |
| outpipe = -1; |
| break; |
| default: |
| break; |
| } |
| |
| if (failed) |
| break; |
| } |
| |
| if (errpipe >= 0 && FD_ISSET (errpipe, &fds)) |
| { |
| switch (read_data (errstr, errpipe, error)) |
| { |
| case READ_FAILED: |
| failed = TRUE; |
| break; |
| case READ_EOF: |
| close_and_invalidate (&errpipe); |
| errpipe = -1; |
| break; |
| default: |
| break; |
| } |
| |
| if (failed) |
| break; |
| } |
| } |
| |
| /* These should only be open still if we had an error. */ |
| |
| if (outpipe >= 0) |
| close_and_invalidate (&outpipe); |
| if (errpipe >= 0) |
| close_and_invalidate (&errpipe); |
| |
| /* Wait for child to exit, even if we have |
| * an error pending. |
| */ |
| again: |
| |
| ret = waitpid (pid, &status, 0); |
| |
| if (ret < 0) |
| { |
| if (errno == EINTR) |
| goto again; |
| else if (errno == ECHILD) |
| { |
| 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."); |
| } |
| else |
| { |
| /* We don't need the exit status. */ |
| } |
| } |
| else |
| { |
| if (!failed) /* avoid error pileups */ |
| { |
| failed = TRUE; |
| |
| g_set_error (error, |
| G_SPAWN_ERROR, |
| G_SPAWN_ERROR_READ, |
| _("Unexpected error in waitpid() (%s)"), |
| g_strerror (errno)); |
| } |
| } |
| } |
| |
| if (failed) |
| { |
| if (outstr) |
| g_string_free (outstr, TRUE); |
| if (errstr) |
| g_string_free (errstr, TRUE); |
| |
| return FALSE; |
| } |
| else |
| { |
| if (exit_status) |
| *exit_status = status; |
| |
| if (standard_output) |
| *standard_output = g_string_free (outstr, FALSE); |
| |
| if (standard_error) |
| *standard_error = g_string_free (errstr, FALSE); |
| |
| return TRUE; |
| } |
| } |
| |
| /** |
| * 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 |
| * @flags: flags from #GSpawnFlags |
| * @child_setup: function to run in the child just before exec() |
| * @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 |
| * @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 PATH shell variable will only |
| * be searched if you pass the %G_SPAWN_SEARCH_PATH flag. |
| * |
| * @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. |
| * |
| * @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 waitpid() or |
| * handle SIGCHLD yourself, or the child will become a zombie. |
| * %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 exec() 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 PATH. %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. |
| * %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). |
| * |
| * @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 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 waitpid() if you specified the %G_SPAWN_DO_NOT_REAP_CHILD flag. |
| * |
| * If non-NULL, the @standard_input, @standard_output, @standard_error |
| * locations will be filled with file descriptors for writing to the child's |
| * standard input or reading from its standard output or standard error. |
| * The caller of g_spawn_async_with_pipes() must close these file descriptors |
| * when they are no longer in use. If these parameters are NULL, the |
| * corresponding pipe won't be created. |
| * |
| * @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 occurs, @child_pid, @standard_input, @standard_output, |
| * and @standard_error will not be filled with valid values. |
| * |
| * Return value: TRUE on success, FALSE if an error was set |
| **/ |
| gboolean |
| g_spawn_async_with_pipes (const gchar *working_directory, |
| gchar **argv, |
| gchar **envp, |
| GSpawnFlags flags, |
| GSpawnChildSetupFunc child_setup, |
| gpointer user_data, |
| gint *child_pid, |
| gint *standard_input, |
| gint *standard_output, |
| gint *standard_error, |
| GError **error) |
| { |
| g_return_val_if_fail (argv != NULL, FALSE); |
| g_return_val_if_fail (standard_output == NULL || |
| !(flags & G_SPAWN_STDOUT_TO_DEV_NULL), FALSE); |
| g_return_val_if_fail (standard_error == NULL || |
| !(flags & G_SPAWN_STDERR_TO_DEV_NULL), FALSE); |
| /* can't inherit stdin if we have an input pipe. */ |
| g_return_val_if_fail (standard_input == NULL || |
| !(flags & G_SPAWN_CHILD_INHERITS_STDIN), FALSE); |
| |
| return fork_exec_with_pipes (!(flags & G_SPAWN_DO_NOT_REAP_CHILD), |
| working_directory, |
| argv, |
| envp, |
| !(flags & G_SPAWN_LEAVE_DESCRIPTORS_OPEN), |
| (flags & G_SPAWN_SEARCH_PATH) != 0, |
| (flags & G_SPAWN_STDOUT_TO_DEV_NULL) != 0, |
| (flags & G_SPAWN_STDERR_TO_DEV_NULL) != 0, |
| (flags & G_SPAWN_CHILD_INHERITS_STDIN) != 0, |
| child_setup, |
| user_data, |
| child_pid, |
| standard_input, |
| standard_output, |
| standard_error, |
| error); |
| } |
| |
| /** |
| * 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 |
| * @error: return location for errors |
| * |
| * A simple version of g_spawn_sync() with little-used parameters |
| * removed, taking a command line instead of an argument vector. See |
| * g_spawn_sync() for full details. @command_line will be parsed by |
| * g_shell_parse_argv(). Unlike g_spawn_sync(), the %G_SPAWN_SEARCH_PATH flag |
| * is enabled. Note that %G_SPAWN_SEARCH_PATH can have security |
| * 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(). |
| * |
| * Return value: TRUE on success, FALSE if an error was set |
| **/ |
| gboolean |
| g_spawn_command_line_sync (const gchar *command_line, |
| gchar **standard_output, |
| gchar **standard_error, |
| gint *exit_status, |
| GError **error) |
| { |
| gboolean retval; |
| gchar **argv = 0; |
| |
| g_return_val_if_fail (command_line != NULL, FALSE); |
| |
| if (!g_shell_parse_argv (command_line, |
| NULL, &argv, |
| error)) |
| return FALSE; |
| |
| retval = g_spawn_sync (NULL, |
| argv, |
| NULL, |
| G_SPAWN_SEARCH_PATH, |
| NULL, |
| NULL, |
| standard_output, |
| standard_error, |
| exit_status, |
| error); |
| g_strfreev (argv); |
| |
| return retval; |
| } |
| |
| /** |
| * g_spawn_command_line_async: |
| * @command_line: a command line |
| * @error: return location for errors |
| * |
| * A simple version of g_spawn_async() that parses a command line with |
| * g_shell_parse_argv() and passes it to g_spawn_async(). Runs a |
| * command line in the background. Unlike g_spawn_async(), the |
| * %G_SPAWN_SEARCH_PATH flag is enabled, other flags are not. Note |
| * that %G_SPAWN_SEARCH_PATH can have security implications, so |
| * consider using g_spawn_async() directly if appropriate. Possible |
| * errors are those from g_shell_parse_argv() and g_spawn_async(). |
| * |
| * Return value: 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; |
| |
| g_return_val_if_fail (command_line != NULL, FALSE); |
| |
| if (!g_shell_parse_argv (command_line, |
| NULL, &argv, |
| error)) |
| return FALSE; |
| |
| retval = g_spawn_async (NULL, |
| argv, |
| NULL, |
| G_SPAWN_SEARCH_PATH, |
| NULL, |
| NULL, |
| NULL, |
| error); |
| g_strfreev (argv); |
| |
| return retval; |
| } |
| |
| static gint |
| exec_err_to_g_error (gint en) |
| { |
| switch (en) |
| { |
| #ifdef EACCES |
| case EACCES: |
| return G_SPAWN_ERROR_ACCES; |
| break; |
| #endif |
| |
| #ifdef EPERM |
| case EPERM: |
| return G_SPAWN_ERROR_PERM; |
| break; |
| #endif |
| |
| #ifdef E2BIG |
| case E2BIG: |
| return G_SPAWN_ERROR_2BIG; |
| break; |
| #endif |
| |
| #ifdef ENOEXEC |
| case ENOEXEC: |
| return G_SPAWN_ERROR_NOEXEC; |
| break; |
| #endif |
| |
| #ifdef ENAMETOOLONG |
| case ENAMETOOLONG: |
| return G_SPAWN_ERROR_NAMETOOLONG; |
| break; |
| #endif |
| |
| #ifdef ENOENT |
| case ENOENT: |
| return G_SPAWN_ERROR_NOENT; |
| break; |
| #endif |
| |
| #ifdef ENOMEM |
| case ENOMEM: |
| return G_SPAWN_ERROR_NOMEM; |
| break; |
| #endif |
| |
| #ifdef ENOTDIR |
| case ENOTDIR: |
| return G_SPAWN_ERROR_NOTDIR; |
| break; |
| #endif |
| |
| #ifdef ELOOP |
| case ELOOP: |
| return G_SPAWN_ERROR_LOOP; |
| break; |
| #endif |
| |
| #ifdef ETXTBUSY |
| case ETXTBUSY: |
| return G_SPAWN_ERROR_TXTBUSY; |
| break; |
| #endif |
| |
| #ifdef EIO |
| case EIO: |
| return G_SPAWN_ERROR_IO; |
| break; |
| #endif |
| |
| #ifdef ENFILE |
| case ENFILE: |
| return G_SPAWN_ERROR_NFILE; |
| break; |
| #endif |
| |
| #ifdef EMFILE |
| case EMFILE: |
| return G_SPAWN_ERROR_MFILE; |
| break; |
| #endif |
| |
| #ifdef EINVAL |
| case EINVAL: |
| return G_SPAWN_ERROR_INVAL; |
| break; |
| #endif |
| |
| #ifdef EISDIR |
| case EISDIR: |
| return G_SPAWN_ERROR_ISDIR; |
| break; |
| #endif |
| |
| #ifdef ELIBBAD |
| case ELIBBAD: |
| return G_SPAWN_ERROR_LIBBAD; |
| break; |
| #endif |
| |
| default: |
| return G_SPAWN_ERROR_FAILED; |
| break; |
| } |
| } |
| |
| static void |
| write_err_and_exit (gint fd, gint msg) |
| { |
| gint en = errno; |
| |
| write (fd, &msg, sizeof(msg)); |
| write (fd, &en, sizeof(en)); |
| |
| _exit (1); |
| } |
| |
| static void |
| set_cloexec (gint fd) |
| { |
| fcntl (fd, F_SETFD, FD_CLOEXEC); |
| } |
| |
| static gint |
| sane_dup2 (gint fd1, gint fd2) |
| { |
| gint ret; |
| |
| retry: |
| ret = dup2 (fd1, fd2); |
| if (ret < 0 && errno == EINTR) |
| goto retry; |
| |
| return ret; |
| } |
| |
| enum |
| { |
| CHILD_CHDIR_FAILED, |
| CHILD_EXEC_FAILED, |
| CHILD_DUP2_FAILED, |
| CHILD_FORK_FAILED |
| }; |
| |
| static void |
| do_exec (gint child_err_report_fd, |
| gint stdin_fd, |
| gint stdout_fd, |
| gint stderr_fd, |
| const gchar *working_directory, |
| gchar **argv, |
| gchar **envp, |
| gboolean close_descriptors, |
| gboolean search_path, |
| gboolean stdout_to_null, |
| gboolean stderr_to_null, |
| gboolean child_inherits_stdin, |
| GSpawnChildSetupFunc child_setup, |
| gpointer user_data) |
| { |
| if (working_directory && chdir (working_directory) < 0) |
| write_err_and_exit (child_err_report_fd, |
| CHILD_CHDIR_FAILED); |
| |
| /* Close all file descriptors but stdin stdout and stderr as |
| * soon as we exec. Note that this includes |
| * child_err_report_fd, which keeps the parent from blocking |
| * forever on the other end of that pipe. |
| */ |
| if (close_descriptors) |
| { |
| gint open_max; |
| gint i; |
| |
| open_max = sysconf (_SC_OPEN_MAX); |
| for (i = 3; i < open_max; i++) |
| set_cloexec (i); |
| } |
| else |
| { |
| /* We need to do child_err_report_fd anyway */ |
| set_cloexec (child_err_report_fd); |
| } |
| |
| /* Redirect pipes as required */ |
| |
| if (stdin_fd >= 0) |
| { |
| /* dup2 can't actually fail here I don't think */ |
| |
| if (sane_dup2 (stdin_fd, 0) < 0) |
| write_err_and_exit (child_err_report_fd, |
| CHILD_DUP2_FAILED); |
| |
| /* ignore this if it doesn't work */ |
| close_and_invalidate (&stdin_fd); |
| } |
| else if (!child_inherits_stdin) |
| { |
| /* Keep process from blocking on a read of stdin */ |
| gint read_null = open ("/dev/null", O_RDONLY); |
| sane_dup2 (read_null, 0); |
| close_and_invalidate (&read_null); |
| } |
| |
| if (stdout_fd >= 0) |
| { |
| /* dup2 can't actually fail here I don't think */ |
| |
| if (sane_dup2 (stdout_fd, 1) < 0) |
| write_err_and_exit (child_err_report_fd, |
| CHILD_DUP2_FAILED); |
| |
| /* ignore this if it doesn't work */ |
| close_and_invalidate (&stdout_fd); |
| } |
| else if (stdout_to_null) |
| { |
| gint write_null = open ("/dev/null", O_WRONLY); |
| sane_dup2 (write_null, 1); |
| close_and_invalidate (&write_null); |
| } |
| |
| if (stderr_fd >= 0) |
| { |
| /* dup2 can't actually fail here I don't think */ |
| |
| if (sane_dup2 (stderr_fd, 2) < 0) |
| write_err_and_exit (child_err_report_fd, |
| CHILD_DUP2_FAILED); |
| |
| /* ignore this if it doesn't work */ |
| close_and_invalidate (&stderr_fd); |
| } |
| else if (stderr_to_null) |
| { |
| gint write_null = open ("/dev/null", O_WRONLY); |
| sane_dup2 (write_null, 2); |
| close_and_invalidate (&write_null); |
| } |
| |
| /* Call user function just before we exec */ |
| if (child_setup) |
| { |
| (* child_setup) (user_data); |
| } |
| |
| g_execute (argv[0], argv, envp, search_path); |
| |
| /* Exec failed */ |
| write_err_and_exit (child_err_report_fd, |
| CHILD_EXEC_FAILED); |
| } |
| |
| static gboolean |
| read_ints (int fd, |
| gint* buf, |
| gint n_ints_in_buf, |
| gint *n_ints_read, |
| GError **error) |
| { |
| gint bytes = 0; |
| |
| while (TRUE) |
| { |
| gint chunk; |
| |
| if (bytes >= sizeof(gint)*2) |
| break; /* give up, who knows what happened, should not be |
| * possible. |
| */ |
| |
| again: |
| chunk = read (fd, |
| ((gchar*)buf) + bytes, |
| sizeof(gint)*n_ints_in_buf - bytes); |
| if (chunk < 0 && errno == EINTR) |
| goto again; |
| |
| if (chunk < 0) |
| { |
| /* 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)); |
| |
| return FALSE; |
| } |
| else if (chunk == 0) |
| break; /* EOF */ |
| else |
| { |
| g_assert (chunk > 0); |
| |
| bytes += chunk; |
| } |
| } |
| |
| *n_ints_read = bytes/4; |
| |
| return TRUE; |
| } |
| |
| static gboolean |
| fork_exec_with_pipes (gboolean intermediate_child, |
| const gchar *working_directory, |
| gchar **argv, |
| gchar **envp, |
| gboolean close_descriptors, |
| gboolean search_path, |
| gboolean stdout_to_null, |
| gboolean stderr_to_null, |
| gboolean child_inherits_stdin, |
| GSpawnChildSetupFunc child_setup, |
| gpointer user_data, |
| gint *child_pid, |
| gint *standard_input, |
| gint *standard_output, |
| gint *standard_error, |
| GError **error) |
| { |
| gint pid; |
| 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 }; |
| gint status; |
| |
| if (!make_pipe (child_err_report_pipe, error)) |
| return FALSE; |
| |
| if (intermediate_child && !make_pipe (child_pid_report_pipe, error)) |
| goto cleanup_and_fail; |
| |
| if (standard_input && !make_pipe (stdin_pipe, error)) |
| goto cleanup_and_fail; |
| |
| if (standard_output && !make_pipe (stdout_pipe, error)) |
| goto cleanup_and_fail; |
| |
| if (standard_error && !make_pipe (stderr_pipe, error)) |
| goto cleanup_and_fail; |
| |
| pid = fork (); |
| |
| if (pid < 0) |
| { |
| g_set_error (error, |
| G_SPAWN_ERROR, |
| G_SPAWN_ERROR_FORK, |
| _("Failed to fork (%s)"), |
| g_strerror (errno)); |
| |
| goto cleanup_and_fail; |
| } |
| else if (pid == 0) |
| { |
| /* Immediate child. This may or may not be the child that |
| * actually execs the new process. |
| */ |
| |
| /* Be sure we crash if the parent exits |
| * and we write to the err_report_pipe |
| */ |
| signal (SIGPIPE, SIG_DFL); |
| |
| /* Close the parent's end of the pipes; |
| * not needed in the close_descriptors case, |
| * though |
| */ |
| close_and_invalidate (&child_err_report_pipe[0]); |
| close_and_invalidate (&child_pid_report_pipe[0]); |
| close_and_invalidate (&stdin_pipe[1]); |
| close_and_invalidate (&stdout_pipe[0]); |
| close_and_invalidate (&stderr_pipe[0]); |
| |
| if (intermediate_child) |
| { |
| /* We need to fork an intermediate child that launches the |
| * final child. The purpose of the intermediate child |
| * is to exit, so we can waitpid() it immediately. |
| * Then the grandchild will not become a zombie. |
| */ |
| gint 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_err_and_exit (child_err_report_pipe[1], |
| CHILD_FORK_FAILED); |
| } |
| else if (grandchild_pid == 0) |
| { |
| do_exec (child_err_report_pipe[1], |
| stdin_pipe[0], |
| stdout_pipe[1], |
| stderr_pipe[1], |
| working_directory, |
| argv, |
| envp, |
| close_descriptors, |
| search_path, |
| stdout_to_null, |
| stderr_to_null, |
| child_inherits_stdin, |
| child_setup, |
| user_data); |
| } |
| else |
| { |
| write (child_pid_report_pipe[1], &grandchild_pid, sizeof(grandchild_pid)); |
| close_and_invalidate (&child_pid_report_pipe[1]); |
| |
| _exit (0); |
| } |
| } |
| else |
| { |
| /* Just run the child. |
| */ |
| |
| do_exec (child_err_report_pipe[1], |
| stdin_pipe[0], |
| stdout_pipe[1], |
| stderr_pipe[1], |
| working_directory, |
| argv, |
| envp, |
| close_descriptors, |
| search_path, |
| stdout_to_null, |
| stderr_to_null, |
| child_inherits_stdin, |
| child_setup, |
| user_data); |
| } |
| } |
| else |
| { |
| /* Parent */ |
| |
| gint buf[2]; |
| gint n_ints = 0; |
| |
| /* Close the uncared-about ends of the pipes */ |
| close_and_invalidate (&child_err_report_pipe[1]); |
| close_and_invalidate (&child_pid_report_pipe[1]); |
| close_and_invalidate (&stdin_pipe[0]); |
| close_and_invalidate (&stdout_pipe[1]); |
| close_and_invalidate (&stderr_pipe[1]); |
| |
| /* If we had an intermediate child, reap it */ |
| if (intermediate_child) |
| { |
| wait_again: |
| if (waitpid (pid, &status, 0) < 0) |
| { |
| if (errno == EINTR) |
| goto wait_again; |
| else if (errno == ECHILD) |
| ; /* do nothing, child already reaped */ |
| else |
| g_warning ("waitpid() should not fail in " |
| "'fork_exec_with_pipes'"); |
| } |
| } |
| |
| |
| if (!read_ints (child_err_report_pipe[0], |
| buf, 2, &n_ints, |
| error)) |
| goto cleanup_and_fail; |
| |
| if (n_ints >= 2) |
| { |
| /* Error from the child. */ |
| |
| switch (buf[0]) |
| { |
| case CHILD_CHDIR_FAILED: |
| g_set_error (error, |
| G_SPAWN_ERROR, |
| G_SPAWN_ERROR_CHDIR, |
| _("Failed to change to directory '%s' (%s)"), |
| working_directory, |
| g_strerror (buf[1])); |
| |
| break; |
| |
| case CHILD_EXEC_FAILED: |
| g_set_error (error, |
| G_SPAWN_ERROR, |
| exec_err_to_g_error (buf[1]), |
| _("Failed to execute child process (%s)"), |
| g_strerror (buf[1])); |
| |
| break; |
| |
| case CHILD_DUP2_FAILED: |
| g_set_error (error, |
| G_SPAWN_ERROR, |
| G_SPAWN_ERROR_FAILED, |
| _("Failed to redirect output or input of child process (%s)"), |
| g_strerror (buf[1])); |
| |
| break; |
| |
| case CHILD_FORK_FAILED: |
| g_set_error (error, |
| G_SPAWN_ERROR, |
| G_SPAWN_ERROR_FORK, |
| _("Failed to fork child process (%s)"), |
| g_strerror (buf[1])); |
| break; |
| |
| default: |
| g_set_error (error, |
| G_SPAWN_ERROR, |
| G_SPAWN_ERROR_FAILED, |
| _("Unknown error executing child process")); |
| break; |
| } |
| |
| goto cleanup_and_fail; |
| } |
| |
| /* Get child pid from intermediate child pipe. */ |
| if (intermediate_child) |
| { |
| n_ints = 0; |
| |
| if (!read_ints (child_pid_report_pipe[0], |
| buf, 1, &n_ints, error)) |
| goto cleanup_and_fail; |
| |
| if (n_ints < 1) |
| { |
| g_set_error (error, |
| G_SPAWN_ERROR, |
| G_SPAWN_ERROR_FAILED, |
| _("Failed to read enough data from child pid pipe (%s)"), |
| g_strerror (errno)); |
| goto cleanup_and_fail; |
| } |
| else |
| { |
| /* we have the child pid */ |
| pid = buf[0]; |
| } |
| } |
| |
| /* Success against all odds! return the information */ |
| |
| if (child_pid) |
| *child_pid = pid; |
| |
| if (standard_input) |
| *standard_input = stdin_pipe[1]; |
| if (standard_output) |
| *standard_output = stdout_pipe[0]; |
| if (standard_error) |
| *standard_error = stderr_pipe[0]; |
| |
| return TRUE; |
| } |
| |
| cleanup_and_fail: |
| close_and_invalidate (&child_err_report_pipe[0]); |
| close_and_invalidate (&child_err_report_pipe[1]); |
| close_and_invalidate (&child_pid_report_pipe[0]); |
| close_and_invalidate (&child_pid_report_pipe[1]); |
| close_and_invalidate (&stdin_pipe[0]); |
| close_and_invalidate (&stdin_pipe[1]); |
| close_and_invalidate (&stdout_pipe[0]); |
| close_and_invalidate (&stdout_pipe[1]); |
| close_and_invalidate (&stderr_pipe[0]); |
| close_and_invalidate (&stderr_pipe[1]); |
| |
| 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) |
| { |
| /* Count the arguments. */ |
| int argc = 0; |
| while (argv[argc]) |
| ++argc; |
| |
| /* Construct an argument list for the shell. */ |
| { |
| gchar **new_argv; |
| |
| new_argv = g_new0 (gchar*, argc + 1); |
| |
| new_argv[0] = (char *) "/bin/sh"; |
| new_argv[1] = (char *) file; |
| while (argc > 1) |
| { |
| new_argv[argc] = argv[argc - 1]; |
| --argc; |
| } |
| |
| /* Execute the shell. */ |
| if (envp) |
| execve (new_argv[0], new_argv, envp); |
| else |
| execv (new_argv[0], new_argv); |
| |
| g_free (new_argv); |
| } |
| } |
| |
| static gchar* |
| my_strchrnul (const gchar *str, gchar c) |
| { |
| gchar *p = (gchar*) str; |
| while (*p && (*p != c)) |
| ++p; |
| |
| return p; |
| } |
| |
| static gint |
| g_execute (const gchar *file, |
| gchar **argv, |
| gchar **envp, |
| gboolean search_path) |
| { |
| if (*file == '\0') |
| { |
| /* We check the simple case first. */ |
| errno = ENOENT; |
| return -1; |
| } |
| |
| if (!search_path || strchr (file, '/') != NULL) |
| { |
| /* Don't search when it contains a slash. */ |
| if (envp) |
| execve (file, argv, envp); |
| else |
| execv (file, argv); |
| |
| if (errno == ENOEXEC) |
| script_execute (file, argv, envp, FALSE); |
| } |
| else |
| { |
| gboolean got_eacces = 0; |
| char *path, *p, *name, *freeme; |
| size_t len; |
| size_t pathlen; |
| |
| path = g_getenv ("PATH"); |
| if (path == NULL) |
| { |
| /* 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'. |
| */ |
| |
| /* In GLib we put . last, for security, and don't use the |
| * unportable confstr(); UNIX98 does not actually specify |
| * what to search if PATH is unset. POSIX may, dunno. |
| */ |
| |
| path = "/bin:/usr/bin:."; |
| } |
| |
| len = strlen (file) + 1; |
| pathlen = strlen (path); |
| freeme = name = g_malloc (pathlen + len + 1); |
| |
| /* Copy the file name at the top, including '\0' */ |
| memcpy (name + pathlen + 1, file, len); |
| name = name + pathlen; |
| /* And add the slash before the filename */ |
| *name = '/'; |
| |
| p = path; |
| do |
| { |
| char *startp; |
| |
| path = p; |
| p = my_strchrnul (path, ':'); |
| |
| if (p == path) |
| /* Two adjacent colons, or a colon at the beginning or the end |
| * of `PATH' means to search the current directory. |
| */ |
| startp = name + 1; |
| else |
| startp = memcpy (name - (p - path), path, p - path); |
| |
| /* Try to execute this name. If it works, execv will not return. */ |
| if (envp) |
| execve (startp, argv, envp); |
| else |
| execv (startp, argv); |
| |
| if (errno == ENOEXEC) |
| script_execute (startp, argv, envp, search_path); |
| |
| switch (errno) |
| { |
| case EACCES: |
| /* 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. |
| */ |
| got_eacces = TRUE; |
| |
| /* FALL THRU */ |
| |
| case ENOENT: |
| #ifdef ESTALE |
| case ESTALE: |
| #endif |
| #ifdef ENOTDIR |
| case ENOTDIR: |
| #endif |
| /* Those errors indicate the file is missing or not executable |
| * by us, in which case we want to just try the next path |
| * directory. |
| */ |
| break; |
| |
| default: |
| /* Some other error means we found an executable file, but |
| * something went wrong executing it; return the error to our |
| * caller. |
| */ |
| g_free (freeme); |
| return -1; |
| } |
| } |
| while (*p++ != '\0'); |
| |
| /* We tried every element and none of them worked. */ |
| if (got_eacces) |
| /* At least one failure was due to permissions, so report that |
| * error. |
| */ |
| errno = EACCES; |
| |
| g_free (freeme); |
| } |
| |
| /* Return the error from the last attempt (probably ENOENT). */ |
| return -1; |
| } |
