commit 6f207dac5ff858aac6827a4cd4ac78aa5d07a801
parent 4414a17e1b79ced4e7fee8d8c6f6e549a30b16aa
Author: FRIGN <dev@frign.de>
Date: Mon, 9 Mar 2015 01:04:34 +0100
Don't return but _exit after failed exec*() and fork()
Quoting POSIX[0]:
"Care should be taken, also, to call _exit() rather than exit() if exec cannot be used, since
exit() flushes and closes standard I/O channels, thereby damaging the parent process' standard
I/O data structures. (Even with fork(), it is wrong to call exit(), since buffered data would
then be flushed twice.)"
[0]: http://pubs.opengroup.org/onlinepubs/009695399/functions/vfork.html
Diffstat:
8 files changed, 30 insertions(+), 22 deletions(-)
diff --git a/chroot.c b/chroot.c
@@ -36,15 +36,14 @@ main(int argc, char *argv[])
if (argc == 1) {
cmd = *shell;
- execvp(*shell, shell);
+ execvp(cmd, shell);
} else {
cmd = argv[1];
- execvp(argv[1], argv + 1);
+ execvp(cmd, argv + 1);
}
savederrno = errno;
weprintf("execvp %s:", cmd);
- _exit(126 + (savederrno == ENOENT));
- return 0; /* not reached */
+ _exit(126 + (savederrno == ENOENT));
}
diff --git a/env.c b/env.c
@@ -18,6 +18,8 @@ usage(void)
int
main(int argc, char *argv[])
{
+ int savederrno;
+
ARGBEGIN {
case 'i':
if (environ)
@@ -35,7 +37,9 @@ main(int argc, char *argv[])
if (*argv) {
execvp(*argv, argv);
- enprintf(126 + (errno == EEXIST), "execvp: %s:", *argv);
+ savederrno = errno;
+ weprintf("execvp %s:", *argv);
+ _exit(126 + (savederrno == EEXIST));
}
for (; environ && *environ; environ++)
diff --git a/nice.c b/nice.c
@@ -44,5 +44,5 @@ main(int argc, char *argv[])
savederrno = errno;
weprintf("execvp %s:", argv[0]);
- return 126 + (savederrno == ENOENT);
+ _exit(126 + (savederrno == ENOENT));
}
diff --git a/nohup.c b/nohup.c
@@ -42,8 +42,7 @@ main(int argc, char *argv[])
execvp(argv[0], argv);
savederrno = errno;
- weprintf("exec %s:", argv[0]);
- _exit(126 + (savederrno == ENOENT));
+ weprintf("execvp %s:", argv[0]);
- return 0; /* not reached */
+ _exit(126 + (savederrno == ENOENT));
}
diff --git a/setsid.c b/setsid.c
@@ -26,7 +26,8 @@ main(int argc, char *argv[])
if (getpgrp() == getpid()) {
switch (fork()) {
case -1:
- eprintf("fork:");
+ weprintf("fork:");
+ _exit(1);
case 0:
break;
default:
@@ -39,5 +40,5 @@ main(int argc, char *argv[])
savederrno = errno;
weprintf("execvp %s:", argv[0]);
- return 126 + (savederrno == ENOENT);
+ _exit(126 + (savederrno == ENOENT));
}
diff --git a/tar.c b/tar.c
@@ -55,7 +55,8 @@ decomp(FILE *fp)
pid = fork();
if (pid < 0) {
- eprintf("fork:");
+ weprintf("fork:");
+ _exit(1);
} else if (!pid) {
dup2(fileno(fp), 0);
dup2(fds[1], 1);
@@ -64,12 +65,13 @@ decomp(FILE *fp)
switch (filtermode) {
case 'j':
- execlp("bzip2", "bzip2", "-cd", (char *)0);
- eprintf("execlp bzip2:");
+ execlp("bzip2", "bzip2", "-cd", NULL);
+ weprintf("execlp bzip2:");
+ _exit(1);
case 'z':
- execlp("gzip", "gzip", "-cd", (char *)0);
- eprintf("execlp gzip:");
- break;
+ execlp("gzip", "gzip", "-cd", NULL);
+ weprintf("execlp gzip:");
+ _exit(1);
}
}
close(fds[1]);
diff --git a/time.c b/time.c
@@ -41,11 +41,12 @@ main(int argc, char *argv[])
switch ((pid = fork())) {
case -1:
- eprintf("fork:");
+ weprintf("fork:");
+ _exit(1);
case 0:
execvp(argv[0], argv);
savederrno = errno;
- weprintf("exec %s:", argv[0]);
+ weprintf("execvp %s:", argv[0]);
_exit(126 + (savederrno == ENOENT));
default:
break;
diff --git a/xargs.c b/xargs.c
@@ -168,13 +168,15 @@ spawn(void)
int savederrno;
pid = fork();
- if (pid < 0)
- eprintf("fork:");
+ if (pid < 0) {
+ weprintf("fork:");
+ _exit(1);
+ }
if (pid == 0) {
execvp(*cmd, cmd);
savederrno = errno;
weprintf("execvp %s:", *cmd);
- _exit(savederrno == ENOENT ? 127 : 126);
+ _exit(126 + (savederrno == ENOENT));
}
waitchld();
}