1 /*- 2 * Copyright (c) 2017 Baptiste Daroussin <bapt@FreeBSD.org> 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer 10 * in this position and unchanged. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR(S) ``AS IS'' AND ANY EXPRESS OR 16 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 17 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 18 * IN NO EVENT SHALL THE AUTHOR(S) BE LIABLE FOR ANY DIRECT, INDIRECT, 19 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 20 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 21 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 22 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 24 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 25 */ 26 27 #include <sys/procdesc.h> 28 #include <sys/wait.h> 29 30 #include <err.h> 31 #include <errno.h> 32 #include <fcntl.h> 33 #include <paths.h> 34 #include <signal.h> 35 #include <spawn.h> 36 #include <stdio.h> 37 #include <stdlib.h> 38 #include <unistd.h> 39 40 #include "pr.h" 41 #include "diff.h" 42 #include "xmalloc.h" 43 44 #define _PATH_PR "/usr/bin/pr" 45 46 extern char **environ; 47 48 struct pr * 49 start_pr(char *file1, char *file2) 50 { 51 int pfd[2]; 52 pid_t pid; 53 char *header; 54 struct pr *pr; 55 posix_spawn_file_actions_t fa; 56 posix_spawnattr_t sa; 57 int error; 58 59 pr = xcalloc(1, sizeof(*pr)); 60 61 xasprintf(&header, "%s %s %s", diffargs, file1, file2); 62 signal(SIGPIPE, SIG_IGN); 63 fflush(stdout); 64 if (pipe(pfd) == -1) 65 err(2, "pipe"); 66 67 if ((error = posix_spawnattr_init(&sa)) != 0) 68 errc(2, error, "posix_spawnattr_init"); 69 if ((error = posix_spawn_file_actions_init(&fa)) != 0) 70 errc(2, error, "posix_spawn_file_actions_init"); 71 72 posix_spawnattr_setprocdescp_np(&sa, &pr->procd, 0); 73 74 if (pfd[0] != STDIN_FILENO) { 75 posix_spawn_file_actions_adddup2(&fa, pfd[0], STDIN_FILENO); 76 posix_spawn_file_actions_addclose(&fa, pfd[0]); 77 } 78 posix_spawn_file_actions_addclose(&fa, pfd[1]); 79 80 char *argv[] = { __DECONST(char *, _PATH_PR), 81 __DECONST(char *, "-h"), header, NULL }; 82 error = posix_spawn(&pid, _PATH_PR, &fa, &sa, argv, environ); 83 if (error != 0) 84 errc(2, error, "could not spawn pr"); 85 86 posix_spawn_file_actions_destroy(&fa); 87 posix_spawnattr_destroy(&sa); 88 89 /* parent */ 90 if (pfd[1] == STDOUT_FILENO) { 91 pr->ostdout = STDOUT_FILENO; 92 } else { 93 if ((pr->ostdout = dup(STDOUT_FILENO)) < 0 || 94 dup2(pfd[1], STDOUT_FILENO) < 0) { 95 err(2, "stdout"); 96 } 97 close(pfd[1]); 98 } 99 close(pfd[0]); 100 free(header); 101 return (pr); 102 } 103 104 /* close the pipe to pr and restore stdout */ 105 void 106 stop_pr(struct pr *pr) 107 { 108 int wstatus; 109 110 if (pr == NULL) 111 return; 112 113 fflush(stdout); 114 if (pr->ostdout != STDOUT_FILENO) { 115 dup2(pr->ostdout, STDOUT_FILENO); 116 close(pr->ostdout); 117 } 118 while (pdwait(pr->procd, &wstatus, WEXITED, NULL, NULL) == -1) { 119 if (errno != EINTR) 120 err(2, "pdwait"); 121 } 122 close(pr->procd); 123 free(pr); 124 if (WIFEXITED(wstatus) && WEXITSTATUS(wstatus) != 0) 125 errx(2, "pr exited abnormally"); 126 else if (WIFSIGNALED(wstatus)) 127 errx(2, "pr killed by signal %d", 128 WTERMSIG(wstatus)); 129 } 130