10 /*----- Licensing notice --------------------------------------------------*
12 * This file is part of sw-tools.
14 * sw-tools is free software; you can redistribute it and/or modify
15 * it under the terms of the GNU General Public License as published by
16 * the Free Software Foundation; either version 2 of the License, or
17 * (at your option) any later version.
19 * sw-tools is distributed in the hope that it will be useful,
20 * but WITHOUT ANY WARRANTY; without even the implied warranty of
21 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
22 * GNU General Public License for more details.
24 * You should have received a copy of the GNU General Public License
25 * along with sw-tools; if not, write to the Free Software Foundation,
26 * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
29 /*----- Header files ------------------------------------------------------*/
41 #include <sys/types.h>
46 #include <sys/socket.h>
50 extern char **environ
;
53 #include <mLib/alloc.h>
54 #include <mLib/bits.h>
55 #include <mLib/dstr.h>
57 #include <mLib/mdwopt.h>
58 #include <mLib/quis.h>
59 #include <mLib/report.h>
68 /*----- Data structures ---------------------------------------------------*/
72 /*----- Static variables --------------------------------------------------*/
74 static int handler
= 0;
75 static rcmd
*rcmds
= RCMD_LINK
;
77 /*----- Packet interface --------------------------------------------------*/
81 * Arguments: @sw_remote@ = pointer to the remote block
82 * @int type@ = packet type to send
83 * @const void *p@ = pointer to packet data
84 * @size_t sz@ = size of data to send
86 * Returns: Zero if it worked, nonzero otherwise.
88 * Use: Sends a data packet. If the type is `data', then `sz' may be
89 * arbitrarily large and is divided into small enough chunks.
90 * Otherwise it's an error to send a packet that's too big.
93 int pksend(sw_remote
*r
, int type
, const void *p
, size_t sz
)
99 /* --- Sort out error conditions --- */
101 if (sz
> PKMAX
&& type
!= PKTYPE_DATA
) {
106 /* --- Main output loop --- */
111 /* --- Set up the packet header --- */
113 chunk
= (sz
> PKMAX ? PKMAX
: sz
);
116 /* --- Write the packet header --- */
119 if (write(r
->fdout
, &h
, PKHEADSZ
) < PKHEADSZ
) {
125 /* --- Write the payload, if there is one --- *
127 * Maybe the OS won't want to bite it all off in one go.
131 ssize_t n
= write(r
->fdout
, q
, chunk
);
132 if (n
< 0 && errno
!= EINTR
)
147 /* --- @pkrecv@ --- *
149 * Arguments: @sw_remote *r@ = remote block
151 * Returns: Packet type received, or @-1@ for an error.
153 * Use: Receives a packet from the remote host. The packet data is
154 * placed in the block's buffer, the block's packet length is
155 * diddled appropriately.
158 int pkrecv(sw_remote
*r
)
165 /* --- Read the packet header --- */
170 n
= read(r
->fdin
, p
, sz
);
171 if (n
< 0 && errno
!= EINTR
)
181 /* --- Hack for error messages --- *
183 * If it doesn't look like a valid packet, read a `chunk' and pretend it's
184 * data. This isn't too bad, because all the packet types are control
185 * codes, and are unlikely to be in a textual message.
187 * Normally what happens here is that something sitting before the `sw'
188 * program fails, reports a plain textual error, and exits. Grabbing the
189 * `last gasp' like this, then, traps that error message and allows
190 * something to report it. The rest ought to be completely silent, so I
191 * get an `unexpected eof' and then drop everything.
193 * This is certainly better than the behaviour otherwise, which is an
194 * @E2BIG@ message reported when the packet size is really ASCII
198 if (h
[2] >= PKTYPE_BOGUS
) {
199 memcpy(r
->buf
, &h
, PKHEADSZ
);
200 n
= read(r
->fdin
, r
->buf
+ PKHEADSZ
, sizeof(r
->buf
) - PKHEADSZ
);
203 r
->sz
= n
+ PKHEADSZ
;
204 return (PKTYPE_DATA
);
207 /* --- Sort out what's going on --- */
218 /* --- Read the packet payload --- */
222 n
= read(r
->fdin
, p
, sz
);
223 if (n
< 0 && errno
!= EINTR
)
236 /*----- Error reporting and exit statuses --------------------------------*/
238 /* --- @swexit@ --- *
240 * Arguments: @sw_remote *r@ = remote context
241 * @int status@ = exit status to return
245 * Use: Reports the exit status via packet protocol and quits.
248 void swexit(sw_remote
*r
, int status
)
250 unsigned char s
= status
;
251 pksend(r
, PKTYPE_STATUS
, &s
, 1);
255 /* --- @swsignal@ --- *
257 * Arguments: @sw_remote *r@ = remote context
258 * @int sig@ = signal ocurrence to return
262 * Use: Reports a signalled-to-death status via packet protocol and
266 void swsignal(sw_remote
*r
, int sig
)
268 #if defined(HAVE_STRSIGNAL)
269 char *s
= strsignal(sig
);
270 #elif defined(HAVE__SYS_SIGLIST)
271 char *s
= _sys_siglist
[sig
];
274 sprintf(s
, "signal %i", sig
);
277 pksend(r
, PKTYPE_STATUS
, s
, strlen(s
) + 1);
281 /* --- @swwait@ --- *
283 * Arguments: @sw_remote *r@ = remote context
284 * @int status@ = status answer from @wait@(2)
288 * Use: Reports a child's demise appropriately, and quits.
291 void swwait(sw_remote
*r
, int status
)
293 if (WIFEXITED(status
))
294 swexit(r
, WEXITSTATUS(status
));
295 else if (WIFSIGNALED(status
))
296 swsignal(r
, WTERMSIG(status
));
301 /* --- @swvprintf@ --- *
303 * Arguments: @sw_remote *r@ = remote context
304 * @const char *format@ = format string
305 * @va_list ap@ = things to format
309 * Use: Writes a string to the remote end. This is the low-level bit
313 void swvprintf(sw_remote
*r
, const char *format
, va_list ap
)
316 dstr_vputf(&d
, format
, &ap
);
317 pksend(r
, PKTYPE_DATA
, d
.buf
, d
.len
);
321 /* --- @swprintf@ --- *
323 * Arguments: @sw_remote *r@ = remote context
324 * @const char *format@ = format string
325 * @...@ = other arguments
329 * Use: Writes a string to the remote end.
332 void swprintf(sw_remote
*r
, const char *format
, ...)
335 va_start(ap
, format
);
336 swvprintf(r
, format
, ap
);
342 * Arguments: @sw_remote *r@ = remote context
343 * @int status@ = exit status to report
344 * @const char *format@ = format string to fill in
345 * @...@ = other arguments
349 * Use: Reports a message and quits.
352 void swdie(sw_remote
*r
, int status
, const char *format
, ...)
357 va_start(ap
, format
);
358 dstr_putf(&d
, "%s [remote]: ", QUIS
);
359 dstr_vputf(&d
, format
, &ap
);
363 pksend(r
, PKTYPE_DATA
, d
.buf
, d
.len
);
368 /*----- Command handling and dispatch -------------------------------------*/
370 /* --- @remote@ --- *
372 * Arguments: @sw_remote *r@ = pointer to remote block
373 * @const char *cmd@ = command to run
374 * @char *argv[]@ = argument array
375 * @char *env[]@ = environment variables
377 * Returns: Doesn't. Reports an exit status through packet protocol and
380 * Use: Dispatches a remote command. At this point, the two code
381 * paths for local and remote invokation have joined again.
384 static void remote(sw_remote
*r
, const char *cmd
, char *argv
[], char *env
[])
386 struct rcmd
*p
, *chosen
= 0;
387 size_t sz
= strlen(cmd
);
389 /* --- Make sure that I can get the exit status of children --- */
391 signal(SIGCHLD
, SIG_DFL
);
393 /* --- Fix up the environment --- */
399 if (env
!= environ
) {
401 env_import(&t
, environ
);
403 env_put(&t
, "SW_ARCH", ARCH
);
404 env_file(&t
, DATADIR
"/sw-env");
405 env
= env_export(&t
);
408 /* --- Dispatch to the command handler --- */
410 for (p
= rcmds
; p
; p
= p
->next
) {
411 if (strncmp(cmd
, p
->name
, sz
) == 0) {
412 if (p
->name
[sz
] == 0) {
416 swdie(r
, 1, "ambiguous remote command name `%s'", cmd
);
422 swdie(r
, 1, "unknown remote command name `%s'", cmd
);
423 chosen
->rcmd(r
, argv
, env
);
426 /*----- Remote invocation -------------------------------------------------*/
428 /* --- @sendargv@ --- *
430 * Arguments: @sw_remote *r@ = pointer to the remote context
431 * @int type@ = packet type to send with
432 * @char *v[]@ = pointer to the array to send
434 * Returns: Zero if OK, nonzero if it failed.
436 * Use: Sends something @argv@-shaped; i.e., an array of strings
437 * terminated by a null pointer.
440 static int sendargv(sw_remote
*r
, int type
, char *v
[])
447 d
.len
++; /* Make the null `real' */
450 e
= pksend(r
, type
, d
.buf
, d
.len
);
455 /* --- @snarfargv@ --- *
457 * Arguments: @const char *buf@ = pointer to buffer
458 * @size_t sz@ = size of buffer
460 * Returns: Pointer to argument array (allocated with @malloc@).
462 * Use: Snarfs the null-terminated strings in the buffer and returns
463 * an array of them. The whole lot, strings and array, is
464 * returned in one big chunk allocated from the heap. Note that
465 * this means it's OK to throw the initial buffer away.
468 static char **snarfargv(const char *buf
, size_t sz
)
470 /* --- Initial setup --- */
477 /* --- Pass one: count the number of arguments --- */
493 /* --- Allocate memory for everything --- */
495 v
= xmalloc((c
+ 1) * sizeof(char *) + sz
+ 1);
496 q
= (char *)(v
+ c
+ 1);
499 /* --- Pass two: set up the arrays --- */
521 /* --- @swrsh_remote@ --- *
523 * Arguments: @const char *cmd@ = the command to perform
525 * Returns: Doesn't. Reports an exit status through packet protocol and
528 * Use: Handles the remote end of a remote job invokation.
531 void swrsh_remote(const char *cmd
)
534 static char *dummy
= 0;
541 /* --- Read packets from the remote host --- */
547 swdie(&r
, 1, "error reading packet: %s", strerror(errno
));
554 argv
= snarfargv(r
.buf
, r
.sz
);
559 env
= snarfargv(r
.buf
, r
.sz
);
565 dir
= xstrdup(r
.buf
);
571 swdie(&r
, 1, "internal error: unexpected packet");
576 /* --- Sort out any missing arguments --- */
586 /* --- Run the command --- */
589 remote(&r
, cmd
, argv
, env
);
590 CATCH
switch (exc_type
) {
592 static char msg
[] = "\nsw [remote]: not enough memory\n";
593 pksend(&r
, PKTYPE_DATA
, msg
, sizeof(msg
) - 1);
597 swdie(&r
, 1, "uncaught exception, type = %lx", exc_type
);
601 /*----- Starting remote jobs ----------------------------------------------*/
603 /* --- @sigchld@ --- *
605 * Arguments: @int sig@ = the signal number
609 * Use: Catches @SIGCHLD@ and reaps any children that have lost.
612 static void sigchld(int sig
)
617 while (waitpid(-1, &status
, WNOHANG
) > 0) {
618 if (WIFEXITED(status
)) {
619 fprintf(stderr
, "reap child with exit status %i\n",
620 WEXITSTATUS(status
));
621 } else if (WIFSIGNALED(status
)) {
622 fprintf(stderr
, "reap child killed by signal %s\n",
623 strsignal(WTERMSIG(status
)));
625 fprintf(stderr
, "reaped bizarre child which is still alive\n");
628 while (waitpid(-1, 0, WNOHANG
) > 0)
636 * Arguments: @sw_remote *r@ = remote process block to look after
637 * @const char *host@ = host to run on (0 for this one)
638 * @const char *cmd@ = remote command to run
639 * @char *argv[]@ = arguments to pass on
641 * Returns: Zero if it worked, nonzero if not.
643 * Use: Runs a command on a remote host. The argument array is
644 * mangled to come out OK at the far end. The environment and
645 * current directory are also passed along, and pop out the
646 * other end unmolested.
649 int swrsh(sw_remote
*r
, const char *host
, const char *cmd
, char *argv
[])
654 /* --- Get a socket pair for communicating with the other end --- */
656 if (socketpair(PF_UNIX
, SOCK_STREAM
, 0, sk
))
659 /* --- Set up a signal handler --- */
663 sa
.sa_handler
= sigchld
;
664 sa
.sa_flags
= SA_NOCLDSTOP
;
666 sa
.sa_flags
|= SA_RESTART
;
668 sigemptyset(&sa
.sa_mask
);
669 sigaction(SIGCHLD
, &sa
, 0);
673 /* --- Fork off a child to cope with stuff --- */
679 /* --- Handle the child process --- *
681 * If this is a local job, then just loop around inside to handle the
682 * `remote' command. Otherwise crank up `rsh' and pass the command over to
683 * a remote copy of myself.
685 * (Why do I need a separate process for local jobs? I don't really, but
686 * it makes everything much simpler when running multiple jobs at the same
693 /* --- Child end of a local job --- */
695 signal(SIGINT
, SIG_DFL
);
696 signal(SIGQUIT
, SIG_DFL
);
699 r
->fdin
= r
->fdout
= sk
[1];
700 remote(r
, cmd
, argv
, environ
);
703 /* --- Local child end of a remote job --- */
712 rsh
= getenv("SW_RSH");
715 execlp(rsh
, rsh
, host
, PATH_SW
, "--remote", cmd
, (char *)0);
718 /* --- I don't expect either to come back --- */
723 /* --- Local sort out of what to do --- *
725 * Either way, I've now got a socket tied to something which speaks my
726 * communication protocol. However, if this is a local job, then I can get
727 * going right away; otherwise, I've got to transmit various bits of
728 * information over the protocol.
731 r
->fdin
= r
->fdout
= sk
[0];
736 if (!getcwd(buf
, sizeof(buf
)))
738 sendargv(r
, PKTYPE_ARGS
, argv
);
739 sendargv(r
, PKTYPE_ENV
, environ
);
740 pksend(r
, PKTYPE_DIR
, buf
, strlen(buf
) + 1);
741 pksend(r
, PKTYPE_GO
, 0, 0);
744 /* --- Ready to rock'n'roll --- */
749 /* --- Tidy up if it failed --- */
758 /*----- Subcommands -------------------------------------------------------*/
760 /* --- @swrsh_rsh@ --- */
762 void rsw_rsh(sw_remote
*r
, char *argv
[], char *env
[])
768 /* --- Create a pipe --- */
771 swdie(r
, 1, "couldn't create pipe: %s", strerror(errno
));
773 /* --- Start the child process up --- */
777 swdie(r
, 1, "fork failed: %s", strerror(errno
));
781 /* --- Use my new environment --- */
783 environ
= env
; /* Yuk. */
785 /* --- Fiddle with pipe file descriptors --- */
793 /* --- Make sure it doesn't get any input --- */
796 fd
= open("/dev/null", O_RDONLY
);
802 /* --- Run the program --- */
804 execvp(argv
[0], argv
);
805 die(1, "couldn't exec `%s': %s", argv
[0], strerror(errno
));
808 /* --- Read the data from the pipe until it closes --- */
812 ssize_t n
= read(pfd
[0], r
->buf
, sizeof(r
->buf
));
814 swdie(r
, 1, "read error: %s", strerror(errno
));
818 pksend(r
, PKTYPE_DATA
, r
->buf
, n
);
822 /* --- Finally, reap the exit status and pass it on --- */
829 swdie(r
, 1, "error reaping child: %s", strerror(errno
));
834 /* --- @sw_rsh@ --- */
836 int sw_rsh(int argc
, char *argv
[])
842 /* --- Check the arguments --- */
845 die(1, "Usage: rsh HOST|ARCH COMMAND [ARGS...]");
847 /* --- Translate architecture names into hostnames --- */
849 if (strcmp(argv
[1], "-") == 0)
852 archent
*a
= arch_lookup(argv
[1], 0);
855 else if (a
->flags
& archFlag_home
)
861 /* --- Start the remote process --- */
863 if (swrsh(&r
, h
, "rsh", argv
+ 2))
864 die(1, "remote shell failed: %s", strerror(errno
));
866 /* --- Cope with packets from the remote process --- */
873 die(1, "error reading packet: %s", strerror(errno
));
875 write(STDOUT_FILENO
, r
.buf
, r
.sz
);
881 moan("command exited due to signal: %s", r
.buf
);
884 moan("command exited with status %i", r
.buf
[0]);
888 moan("command exited unexpectedly");
891 die(1, "unexpected packet type");
895 /* --- Finished --- */
902 /*----- That's all, folks -------------------------------------------------*/