diff options
Diffstat (limited to 'src/shared/pager.c')
-rw-r--r-- | src/shared/pager.c | 143 |
1 files changed, 0 insertions, 143 deletions
diff --git a/src/shared/pager.c b/src/shared/pager.c deleted file mode 100644 index 488a12c763..0000000000 --- a/src/shared/pager.c +++ /dev/null @@ -1,143 +0,0 @@ -/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/ - -/*** - This file is part of systemd. - - Copyright 2010 Lennart Poettering - - systemd 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 2.1 of the License, or - (at your option) any later version. - - systemd 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 systemd; If not, see <http://www.gnu.org/licenses/>. -***/ - -#include <sys/types.h> -#include <fcntl.h> -#include <stdlib.h> -#include <unistd.h> -#include <string.h> -#include <sys/prctl.h> - -#include "pager.h" -#include "util.h" -#include "macro.h" - -static pid_t pager_pid = 0; - -_noreturn_ static void pager_fallback(void) { - ssize_t n; - do { - n = splice(STDIN_FILENO, NULL, STDOUT_FILENO, NULL, 64*1024, 0); - } while (n > 0); - if (n < 0) { - log_error("Internal pager failed: %m"); - _exit(EXIT_FAILURE); - } - _exit(EXIT_SUCCESS); -} - -int pager_open(void) { - int fd[2]; - const char *pager; - pid_t parent_pid; - int r; - - if (pager_pid > 0) - return 1; - - if ((pager = getenv("SYSTEMD_PAGER")) || (pager = getenv("PAGER"))) - if (!*pager || streq(pager, "cat")) - return 0; - - if (!on_tty()) - return 0; - - /* Determine and cache number of columns before we spawn the - * pager so that we get the value from the actual tty */ - columns(); - - if (pipe(fd) < 0) { - log_error("Failed to create pager pipe: %m"); - return -errno; - } - - parent_pid = getpid(); - - pager_pid = fork(); - if (pager_pid < 0) { - r = -errno; - log_error("Failed to fork pager: %m"); - close_pipe(fd); - return r; - } - - /* In the child start the pager */ - if (pager_pid == 0) { - - dup2(fd[0], STDIN_FILENO); - close_pipe(fd); - - setenv("LESS", "FRSX", 0); - - /* Make sure the pager goes away when the parent dies */ - if (prctl(PR_SET_PDEATHSIG, SIGTERM) < 0) - _exit(EXIT_FAILURE); - - /* Check whether our parent died before we were able - * to set the death signal */ - if (getppid() != parent_pid) - _exit(EXIT_SUCCESS); - - if (pager) { - execlp(pager, pager, NULL); - execl("/bin/sh", "sh", "-c", pager, NULL); - } - - /* Debian's alternatives command for pagers is - * called 'pager'. Note that we do not call - * sensible-pagers here, since that is just a - * shell script that implements a logic that - * is similar to this one anyway, but is - * Debian-specific. */ - execlp("pager", "pager", NULL); - - execlp("less", "less", NULL); - execlp("more", "more", NULL); - - pager_fallback(); - /* not reached */ - } - - /* Return in the parent */ - if (dup2(fd[1], STDOUT_FILENO) < 0) { - log_error("Failed to duplicate pager pipe: %m"); - return -errno; - } - - close_pipe(fd); - return 1; -} - -void pager_close(void) { - - if (pager_pid <= 0) - return; - - /* Inform pager that we are done */ - fclose(stdout); - kill(pager_pid, SIGCONT); - wait_for_terminate(pager_pid, NULL); - pager_pid = 0; -} - -bool pager_have(void) { - return pager_pid > 0; -} |