sendmail: document and fix usage of fd #4, fix check for helper failure.

function                                             old     new   delta
packed_usage                                       25663   25694     +31
signal_handler                                       191     215     +24
kill_helper                                           22      31      +9
launch_helper                                        194     184     -10
get_cred_or_die                                      142     129     -13
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 3/2 up/down: 64/-23)             Total: 41 bytes
This commit is contained in:
Denis Vlasenko 2009-03-04 17:56:00 +00:00
parent 5a2ad699fc
commit 021de3f029
2 changed files with 28 additions and 24 deletions

View File

@ -3651,6 +3651,7 @@
"\n -H 'prog args' Run connection helper. E.g. openssl for encryption:" \
"\n -H 'exec openssl s_client -quiet -tls1 -starttls smtp" \
"\n -connect smtp.gmail.com:25' <email.txt" \
"\n [4<username_and_passwd.txt]" \
"\n -S server[:port] Server" \
) \
USE_FEATURE_SENDMAIL_MAILXX( \

View File

@ -11,9 +11,10 @@
static void kill_helper(void)
{
// TODO!!!: is there more elegant way to terminate child on program failure?
if (G.helper_pid > 0)
if (G.helper_pid > 0) {
kill(G.helper_pid, SIGTERM);
G.helper_pid = 0;
}
}
// generic signal handler
@ -26,11 +27,14 @@ static void signal_handler(int signo)
}
// SIGCHLD. reap zombies
if (safe_waitpid(G.helper_pid, &err, WNOHANG) > 0)
if (safe_waitpid(G.helper_pid, &err, WNOHANG) > 0) {
if (WIFSIGNALED(err))
bb_error_msg_and_die("helper killed by signal %u", WTERMSIG(err));
if (WIFEXITED(err)) {
G.helper_pid = 0;
if (WEXITSTATUS(err))
bb_error_msg_and_die("child exited (%d)", WEXITSTATUS(err));
bb_error_msg_and_die("helper exited (%u)", WEXITSTATUS(err));
}
}
#undef err
}
@ -38,32 +42,35 @@ static void signal_handler(int signo)
void FAST_FUNC launch_helper(const char **argv)
{
// setup vanilla unidirectional pipes interchange
int idx;
int i;
int pipes[4];
xpipe(pipes);
xpipe(pipes + 2);
G.helper_pid = vfork();
if (G.helper_pid < 0)
bb_perror_msg_and_die("vfork");
idx = (!G.helper_pid) * 2;
xdup2(pipes[idx], STDIN_FILENO);
xdup2(pipes[3-idx], STDOUT_FILENO);
if (ENABLE_FEATURE_CLEAN_UP)
for (int i = 4; --i >= 0; )
if (pipes[i] > STDOUT_FILENO)
close(pipes[i]);
i = (!G.helper_pid) * 2; // for parent:0, for child:2
close(pipes[i + 1]); // 1 or 3 - closing one write end
close(pipes[2 - i]); // 2 or 0 - closing one read end
xmove_fd(pipes[i], STDIN_FILENO); // 0 or 2 - using other read end
xmove_fd(pipes[3 - i], STDOUT_FILENO); // 3 or 1 - other write end
if (!G.helper_pid) {
// child: try to execute connection helper
BB_EXECVP(*argv, (char **)argv);
_exit(127);
}
// parent: check whether child is alive
// parent
bb_signals(0
+ (1 << SIGCHLD)
+ (1 << SIGALRM)
, signal_handler);
signal_handler(SIGCHLD);
// check whether child is alive
//redundant:signal_handler(SIGCHLD);
// child seems OK -> parent goes on
atexit(kill_helper);
}
@ -226,17 +233,13 @@ void FAST_FUNC decode_base64(FILE *src_stream, FILE *dst_stream)
*/
void FAST_FUNC get_cred_or_die(int fd)
{
// either from TTY
if (isatty(fd)) {
G.user = xstrdup(bb_ask_stdin("User: "));
G.pass = xstrdup(bb_ask_stdin("Password: "));
// or from STDIN
G.user = xstrdup(bb_ask(fd, /* timeout: */ 0, "User: "));
G.pass = xstrdup(bb_ask(fd, /* timeout: */ 0, "Password: "));
} else {
FILE *fp = fdopen(fd, "r");
G.user = xmalloc_fgetline(fp);
G.pass = xmalloc_fgetline(fp);
fclose(fp);
G.user = xmalloc_reads(fd, /* pfx: */ NULL, /* maxsize: */ NULL);
G.pass = xmalloc_reads(fd, /* pfx: */ NULL, /* maxsize: */ NULL);
}
if (!G.user || !*G.user || !G.pass || !*G.pass)
if (!G.user || !*G.user || !G.pass)
bb_error_msg_and_die("no username or password");
}