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Diffstat (limited to 'usr.bin/mail/popen.c')
-rw-r--r-- | usr.bin/mail/popen.c | 373 |
1 files changed, 373 insertions, 0 deletions
diff --git a/usr.bin/mail/popen.c b/usr.bin/mail/popen.c new file mode 100644 index 0000000..467d24a --- /dev/null +++ b/usr.bin/mail/popen.c @@ -0,0 +1,373 @@ +/* + * Copyright (c) 1980, 1993 + * The Regents of the University of California. All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. All advertising materials mentioning features or use of this software + * must display the following acknowledgement: + * This product includes software developed by the University of + * California, Berkeley and its contributors. + * 4. Neither the name of the University nor the names of its contributors + * may be used to endorse or promote products derived from this software + * without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + */ + +#ifndef lint +static char sccsid[] = "@(#)popen.c 8.1 (Berkeley) 6/6/93"; +#endif /* not lint */ + +#include "rcv.h" +#include <sys/wait.h> +#include <fcntl.h> +#include "extern.h" + +#define READ 0 +#define WRITE 1 + +struct fp { + FILE *fp; + int pipe; + int pid; + struct fp *link; +}; +static struct fp *fp_head; + +struct child { + int pid; + char done; + char free; + union wait status; + struct child *link; +}; +static struct child *child; +static struct child *findchild __P((int)); +static void delchild __P((struct child *)); + +FILE * +Fopen(file, mode) + char *file, *mode; +{ + FILE *fp; + + if ((fp = fopen(file, mode)) != NULL) { + register_file(fp, 0, 0); + (void) fcntl(fileno(fp), F_SETFD, 1); + } + return fp; +} + +FILE * +Fdopen(fd, mode) + int fd; + char *mode; +{ + FILE *fp; + + if ((fp = fdopen(fd, mode)) != NULL) { + register_file(fp, 0, 0); + (void) fcntl(fileno(fp), F_SETFD, 1); + } + return fp; +} + +int +Fclose(fp) + FILE *fp; +{ + unregister_file(fp); + return fclose(fp); +} + +FILE * +Popen(cmd, mode) + char *cmd; + char *mode; +{ + int p[2]; + int myside, hisside, fd0, fd1; + int pid; + FILE *fp; + + if (pipe(p) < 0) + return NULL; + (void) fcntl(p[READ], F_SETFD, 1); + (void) fcntl(p[WRITE], F_SETFD, 1); + if (*mode == 'r') { + myside = p[READ]; + fd0 = -1; + hisside = fd1 = p[WRITE]; + } else { + myside = p[WRITE]; + hisside = fd0 = p[READ]; + fd1 = -1; + } + if ((pid = start_command(cmd, 0, fd0, fd1, NOSTR, NOSTR, NOSTR)) < 0) { + close(p[READ]); + close(p[WRITE]); + return NULL; + } + (void) close(hisside); + if ((fp = fdopen(myside, mode)) != NULL) + register_file(fp, 1, pid); + return fp; +} + +int +Pclose(ptr) + FILE *ptr; +{ + int i; + int omask; + + i = file_pid(ptr); + unregister_file(ptr); + (void) fclose(ptr); + omask = sigblock(sigmask(SIGINT)|sigmask(SIGHUP)); + i = wait_child(i); + sigsetmask(omask); + return i; +} + +void +close_all_files() +{ + + while (fp_head) + if (fp_head->pipe) + (void) Pclose(fp_head->fp); + else + (void) Fclose(fp_head->fp); +} + +void +register_file(fp, pipe, pid) + FILE *fp; + int pipe, pid; +{ + struct fp *fpp; + + if ((fpp = (struct fp *) malloc(sizeof *fpp)) == NULL) + panic("Out of memory"); + fpp->fp = fp; + fpp->pipe = pipe; + fpp->pid = pid; + fpp->link = fp_head; + fp_head = fpp; +} + +void +unregister_file(fp) + FILE *fp; +{ + struct fp **pp, *p; + + for (pp = &fp_head; p = *pp; pp = &p->link) + if (p->fp == fp) { + *pp = p->link; + free((char *) p); + return; + } + panic("Invalid file pointer"); +} + +file_pid(fp) + FILE *fp; +{ + struct fp *p; + + for (p = fp_head; p; p = p->link) + if (p->fp == fp) + return (p->pid); + panic("Invalid file pointer"); + /*NOTREACHED*/ +} + +/* + * Run a command without a shell, with optional arguments and splicing + * of stdin and stdout. The command name can be a sequence of words. + * Signals must be handled by the caller. + * "Mask" contains the signals to ignore in the new process. + * SIGINT is enabled unless it's in the mask. + */ +/*VARARGS4*/ +int +run_command(cmd, mask, infd, outfd, a0, a1, a2) + char *cmd; + int mask, infd, outfd; + char *a0, *a1, *a2; +{ + int pid; + + if ((pid = start_command(cmd, mask, infd, outfd, a0, a1, a2)) < 0) + return -1; + return wait_command(pid); +} + +/*VARARGS4*/ +int +start_command(cmd, mask, infd, outfd, a0, a1, a2) + char *cmd; + int mask, infd, outfd; + char *a0, *a1, *a2; +{ + int pid; + + if ((pid = vfork()) < 0) { + perror("fork"); + return -1; + } + if (pid == 0) { + char *argv[100]; + int i = getrawlist(cmd, argv, sizeof argv / sizeof *argv); + + if ((argv[i++] = a0) != NOSTR && + (argv[i++] = a1) != NOSTR && + (argv[i++] = a2) != NOSTR) + argv[i] = NOSTR; + prepare_child(mask, infd, outfd); + execvp(argv[0], argv); + perror(argv[0]); + _exit(1); + } + return pid; +} + +void +prepare_child(mask, infd, outfd) + int mask, infd, outfd; +{ + int i; + + /* + * All file descriptors other than 0, 1, and 2 are supposed to be + * close-on-exec. + */ + if (infd >= 0) + dup2(infd, 0); + if (outfd >= 0) + dup2(outfd, 1); + for (i = 1; i <= NSIG; i++) + if (mask & sigmask(i)) + (void) signal(i, SIG_IGN); + if ((mask & sigmask(SIGINT)) == 0) + (void) signal(SIGINT, SIG_DFL); + (void) sigsetmask(0); +} + +int +wait_command(pid) + int pid; +{ + + if (wait_child(pid) < 0) { + printf("Fatal error in process.\n"); + return -1; + } + return 0; +} + +static struct child * +findchild(pid) + int pid; +{ + register struct child **cpp; + + for (cpp = &child; *cpp != NULL && (*cpp)->pid != pid; + cpp = &(*cpp)->link) + ; + if (*cpp == NULL) { + *cpp = (struct child *) malloc(sizeof (struct child)); + (*cpp)->pid = pid; + (*cpp)->done = (*cpp)->free = 0; + (*cpp)->link = NULL; + } + return *cpp; +} + +static void +delchild(cp) + register struct child *cp; +{ + register struct child **cpp; + + for (cpp = &child; *cpp != cp; cpp = &(*cpp)->link) + ; + *cpp = cp->link; + free((char *) cp); +} + +void +sigchild(signo) + int signo; +{ + int pid; + union wait status; + register struct child *cp; + + while ((pid = + wait3((int *)&status, WNOHANG, (struct rusage *)0)) > 0) { + cp = findchild(pid); + if (cp->free) + delchild(cp); + else { + cp->done = 1; + cp->status = status; + } + } +} + +union wait wait_status; + +/* + * Wait for a specific child to die. + */ +int +wait_child(pid) + int pid; +{ + int mask = sigblock(sigmask(SIGCHLD)); + register struct child *cp = findchild(pid); + + while (!cp->done) + sigpause(mask); + wait_status = cp->status; + delchild(cp); + sigsetmask(mask); + return wait_status.w_status ? -1 : 0; +} + +/* + * Mark a child as don't care. + */ +void +free_child(pid) + int pid; +{ + int mask = sigblock(sigmask(SIGCHLD)); + register struct child *cp = findchild(pid); + + if (cp->done) + delchild(cp); + else + cp->free = 1; + sigsetmask(mask); +} |