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1.1 deraadt 1: /*
2: * Copyright (c) 1980, 1993
3: * The Regents of the University of California. 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: * 2. Redistributions in binary form must reproduce the above copyright
11: * notice, this list of conditions and the following disclaimer in the
12: * documentation and/or other materials provided with the distribution.
13: * 3. All advertising materials mentioning features or use of this software
14: * must display the following acknowledgement:
15: * This product includes software developed by the University of
16: * California, Berkeley and its contributors.
17: * 4. Neither the name of the University nor the names of its contributors
18: * may be used to endorse or promote products derived from this software
19: * without specific prior written permission.
20: *
21: * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22: * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23: * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24: * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25: * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26: * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27: * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28: * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29: * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30: * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31: * SUCH DAMAGE.
32: */
33:
34: #ifndef lint
35: static char sccsid[] = "from: @(#)popen.c 8.1 (Berkeley) 6/6/93";
36: static char rcsid[] = "$Id: popen.c,v 1.3 1994/06/29 05:09:38 deraadt Exp $";
37: #endif /* not lint */
38:
39: #include "rcv.h"
40: #include <sys/wait.h>
41: #include <fcntl.h>
42: #include "extern.h"
43:
44: #define READ 0
45: #define WRITE 1
46:
47: struct fp {
48: FILE *fp;
49: int pipe;
50: int pid;
51: struct fp *link;
52: };
53: static struct fp *fp_head;
54:
55: struct child {
56: int pid;
57: char done;
58: char free;
59: union wait status;
60: struct child *link;
61: };
62: static struct child *child;
63: static struct child *findchild __P((int));
64: static void delchild __P((struct child *));
65:
66: FILE *
67: Fopen(file, mode)
68: char *file, *mode;
69: {
70: FILE *fp;
71:
72: if ((fp = fopen(file, mode)) != NULL) {
73: register_file(fp, 0, 0);
74: (void) fcntl(fileno(fp), F_SETFD, 1);
75: }
76: return fp;
77: }
78:
79: FILE *
80: Fdopen(fd, mode)
81: int fd;
82: char *mode;
83: {
84: FILE *fp;
85:
86: if ((fp = fdopen(fd, mode)) != NULL) {
87: register_file(fp, 0, 0);
88: (void) fcntl(fileno(fp), F_SETFD, 1);
89: }
90: return fp;
91: }
92:
93: int
94: Fclose(fp)
95: FILE *fp;
96: {
97: unregister_file(fp);
98: return fclose(fp);
99: }
100:
101: FILE *
102: Popen(cmd, mode)
103: char *cmd;
104: char *mode;
105: {
106: int p[2];
107: int myside, hisside, fd0, fd1;
108: int pid;
109: FILE *fp;
110:
111: if (pipe(p) < 0)
112: return NULL;
113: (void) fcntl(p[READ], F_SETFD, 1);
114: (void) fcntl(p[WRITE], F_SETFD, 1);
115: if (*mode == 'r') {
116: myside = p[READ];
117: fd0 = -1;
118: hisside = fd1 = p[WRITE];
119: } else {
120: myside = p[WRITE];
121: hisside = fd0 = p[READ];
122: fd1 = -1;
123: }
124: if ((pid = start_command(cmd, 0, fd0, fd1, NOSTR, NOSTR, NOSTR)) < 0) {
125: close(p[READ]);
126: close(p[WRITE]);
127: return NULL;
128: }
129: (void) close(hisside);
130: if ((fp = fdopen(myside, mode)) != NULL)
131: register_file(fp, 1, pid);
132: return fp;
133: }
134:
135: int
136: Pclose(ptr)
137: FILE *ptr;
138: {
139: int i;
140: int omask;
141:
142: i = file_pid(ptr);
143: unregister_file(ptr);
144: (void) fclose(ptr);
145: omask = sigblock(sigmask(SIGINT)|sigmask(SIGHUP));
146: i = wait_child(i);
147: sigsetmask(omask);
148: return i;
149: }
150:
151: void
152: close_all_files()
153: {
154:
155: while (fp_head)
156: if (fp_head->pipe)
157: (void) Pclose(fp_head->fp);
158: else
159: (void) Fclose(fp_head->fp);
160: }
161:
162: void
163: register_file(fp, pipe, pid)
164: FILE *fp;
165: int pipe, pid;
166: {
167: struct fp *fpp;
168:
169: if ((fpp = (struct fp *) malloc(sizeof *fpp)) == NULL)
170: panic("Out of memory");
171: fpp->fp = fp;
172: fpp->pipe = pipe;
173: fpp->pid = pid;
174: fpp->link = fp_head;
175: fp_head = fpp;
176: }
177:
178: void
179: unregister_file(fp)
180: FILE *fp;
181: {
182: struct fp **pp, *p;
183:
184: for (pp = &fp_head; p = *pp; pp = &p->link)
185: if (p->fp == fp) {
186: *pp = p->link;
187: free((char *) p);
188: return;
189: }
190: panic("Invalid file pointer");
191: }
192:
193: file_pid(fp)
194: FILE *fp;
195: {
196: struct fp *p;
197:
198: for (p = fp_head; p; p = p->link)
199: if (p->fp == fp)
200: return (p->pid);
201: panic("Invalid file pointer");
202: /*NOTREACHED*/
203: }
204:
205: /*
206: * Run a command without a shell, with optional arguments and splicing
207: * of stdin and stdout. The command name can be a sequence of words.
208: * Signals must be handled by the caller.
209: * "Mask" contains the signals to ignore in the new process.
210: * SIGINT is enabled unless it's in the mask.
211: */
212: /*VARARGS4*/
213: int
214: run_command(cmd, mask, infd, outfd, a0, a1, a2)
215: char *cmd;
216: int mask, infd, outfd;
217: char *a0, *a1, *a2;
218: {
219: int pid;
220:
221: if ((pid = start_command(cmd, mask, infd, outfd, a0, a1, a2)) < 0)
222: return -1;
223: return wait_command(pid);
224: }
225:
226: /*VARARGS4*/
227: int
228: start_command(cmd, mask, infd, outfd, a0, a1, a2)
229: char *cmd;
230: int mask, infd, outfd;
231: char *a0, *a1, *a2;
232: {
233: int pid;
234:
235: if ((pid = vfork()) < 0) {
236: perror("fork");
237: return -1;
238: }
239: if (pid == 0) {
240: char *argv[100];
241: int i = getrawlist(cmd, argv, sizeof argv / sizeof *argv);
242:
243: if ((argv[i++] = a0) != NOSTR &&
244: (argv[i++] = a1) != NOSTR &&
245: (argv[i++] = a2) != NOSTR)
246: argv[i] = NOSTR;
247: prepare_child(mask, infd, outfd);
248: execvp(argv[0], argv);
249: perror(argv[0]);
250: _exit(1);
251: }
252: return pid;
253: }
254:
255: void
256: prepare_child(mask, infd, outfd)
257: int mask, infd, outfd;
258: {
259: int i;
260:
261: /*
262: * All file descriptors other than 0, 1, and 2 are supposed to be
263: * close-on-exec.
264: */
265: if (infd >= 0)
266: dup2(infd, 0);
267: if (outfd >= 0)
268: dup2(outfd, 1);
269: for (i = 1; i <= NSIG; i++)
270: if (mask & sigmask(i))
271: (void) signal(i, SIG_IGN);
272: if ((mask & sigmask(SIGINT)) == 0)
273: (void) signal(SIGINT, SIG_DFL);
274: (void) sigsetmask(0);
275: }
276:
277: int
278: wait_command(pid)
279: int pid;
280: {
281:
282: if (wait_child(pid) < 0) {
283: printf("Fatal error in process.\n");
284: return -1;
285: }
286: return 0;
287: }
288:
289: static struct child *
290: findchild(pid)
291: int pid;
292: {
293: register struct child **cpp;
294:
295: for (cpp = &child; *cpp != NULL && (*cpp)->pid != pid;
296: cpp = &(*cpp)->link)
297: ;
298: if (*cpp == NULL) {
299: *cpp = (struct child *) malloc(sizeof (struct child));
300: (*cpp)->pid = pid;
301: (*cpp)->done = (*cpp)->free = 0;
302: (*cpp)->link = NULL;
303: }
304: return *cpp;
305: }
306:
307: static void
308: delchild(cp)
309: register struct child *cp;
310: {
311: register struct child **cpp;
312:
313: for (cpp = &child; *cpp != cp; cpp = &(*cpp)->link)
314: ;
315: *cpp = cp->link;
316: free((char *) cp);
317: }
318:
319: void
320: sigchild(signo)
321: int signo;
322: {
323: int pid;
324: union wait status;
325: register struct child *cp;
326:
327: while ((pid =
328: wait3((int *)&status, WNOHANG, (struct rusage *)0)) > 0) {
329: cp = findchild(pid);
330: if (cp->free)
331: delchild(cp);
332: else {
333: cp->done = 1;
334: cp->status = status;
335: }
336: }
337: }
338:
339: union wait wait_status;
340:
341: /*
342: * Wait for a specific child to die.
343: */
344: int
345: wait_child(pid)
346: int pid;
347: {
348: int mask = sigblock(sigmask(SIGCHLD));
349: register struct child *cp = findchild(pid);
350:
351: while (!cp->done)
352: sigpause(mask);
353: wait_status = cp->status;
354: delchild(cp);
355: sigsetmask(mask);
356: return wait_status.w_status ? -1 : 0;
357: }
358:
359: /*
360: * Mark a child as don't care.
361: */
362: void
363: free_child(pid)
364: int pid;
365: {
366: int mask = sigblock(sigmask(SIGCHLD));
367: register struct child *cp = findchild(pid);
368:
369: if (cp->done)
370: delchild(cp);
371: else
372: cp->free = 1;
373: sigsetmask(mask);
374: }