Special code for restarting disk drivers (-c flag in service).

This commit is contained in:
Philip Homburg 2006-05-11 14:58:33 +00:00
parent 773844a816
commit e4967b06bb
6 changed files with 551 additions and 27 deletions

View file

@ -17,7 +17,7 @@ UTIL_LIBS = -lsys
LIBS = -lsys -lsysutil
UTIL_OBJ = service.o
OBJ = main.o manager.o
OBJ = exec.o main.o manager.o
# build local binary
all build: $(SERVER) $(UTIL)
@ -25,7 +25,7 @@ $(UTIL): $(UTIL_OBJ)
$(CC) -o $@ $(LDFLAGS) $(UTIL_OBJ) $(UTIL_LIBS)
$(SERVER): $(OBJ)
$(CC) -o $@ $(LDFLAGS) $(OBJ) $(LIBS)
install -S 16k $@
install -S 48k $@
# install with other servers
install: /bin/$(UTIL) /usr/sbin/$(SERVER)

431
servers/rs/exec.c Normal file
View file

@ -0,0 +1,431 @@
#include "inc.h"
#include <a.out.h>
#define BLOCK_SIZE 1024
static void do_exec(int proc_e, char *exec, size_t exec_len, char *progname,
char *frame, int frame_len);
FORWARD _PROTOTYPE( int read_header, (char *exec, size_t exec_len, int *sep_id,
vir_bytes *text_bytes, vir_bytes *data_bytes,
vir_bytes *bss_bytes, phys_bytes *tot_bytes, vir_bytes *pc,
int *hdrlenp) );
FORWARD _PROTOTYPE( int exec_newmem, (int proc_e, vir_bytes text_bytes,
vir_bytes data_bytes, vir_bytes bss_bytes, vir_bytes tot_bytes,
vir_bytes frame_len, int sep_id,
Dev_t st_dev, ino_t st_ino, time_t st_ctime, char *progname,
int new_uid, int new_gid,
vir_bytes *stack_topp, int *load_textp, int *allow_setuidp) );
FORWARD _PROTOTYPE( int exec_restart, (int proc_e, int result) );
FORWARD _PROTOTYPE( void patch_ptr, (char stack[ARG_MAX],
vir_bytes base) );
FORWARD _PROTOTYPE( int read_seg, (char *exec, size_t exec_len, off_t off,
int proc_e, int seg, phys_bytes seg_bytes) );
static int self_e= NONE;
int dev_execve(int proc_e, char *exec, size_t exec_len, char **argv,
char **Xenvp)
{
char * const *ap;
char * const *ep;
char *frame;
char **vp;
char *sp, *progname;
size_t argc;
size_t frame_size;
size_t string_off;
size_t n;
int ov;
message m;
/* Assumptions: size_t and char *, it's all the same thing. */
/* Create a stack image that only needs to be patched up slightly
* by the kernel to be used for the process to be executed.
*/
ov= 0; /* No overflow yet. */
frame_size= 0; /* Size of the new initial stack. */
string_off= 0; /* Offset to start of the strings. */
argc= 0; /* Argument count. */
for (ap= argv; *ap != NULL; ap++) {
n = sizeof(*ap) + strlen(*ap) + 1;
frame_size+= n;
if (frame_size < n) ov= 1;
string_off+= sizeof(*ap);
argc++;
}
#if 0
printf("here: %s, %d\n", __FILE__, __LINE__);
for (ep= envp; *ep != NULL; ep++) {
n = sizeof(*ep) + strlen(*ep) + 1;
frame_size+= n;
if (frame_size < n) ov= 1;
string_off+= sizeof(*ap);
}
#endif
/* Add an argument count and two terminating nulls. */
frame_size+= sizeof(argc) + sizeof(*ap) + sizeof(*ep);
string_off+= sizeof(argc) + sizeof(*ap) + sizeof(*ep);
/* Align. */
frame_size= (frame_size + sizeof(char *) - 1) & ~(sizeof(char *) - 1);
/* The party is off if there is an overflow. */
if (ov || frame_size < 3 * sizeof(char *)) {
errno= E2BIG;
return -1;
}
/* Allocate space for the stack frame. */
if ((frame = (char *) sbrk(frame_size)) == (char *) -1) {
errno = E2BIG;
return -1;
}
/* Set arg count, init pointers to vector and string tables. */
* (size_t *) frame = argc;
vp = (char **) (frame + sizeof(argc));
sp = frame + string_off;
/* Load the argument vector and strings. */
for (ap= argv; *ap != NULL; ap++) {
*vp++= (char *) (sp - frame);
n= strlen(*ap) + 1;
memcpy(sp, *ap, n);
sp+= n;
}
*vp++= NULL;
#if 0
/* Load the environment vector and strings. */
for (ep= envp; *ep != NULL; ep++) {
*vp++= (char *) (sp - frame);
n= strlen(*ep) + 1;
memcpy(sp, *ep, n);
sp+= n;
}
#endif
*vp++= NULL;
/* Padding. */
while (sp < frame + frame_size) *sp++= 0;
(progname=strrchr(argv[0], '/')) ? progname++ : (progname=argv[0]);
do_exec(proc_e, exec, exec_len, progname, frame, frame_size);
/* Failure, return the memory used for the frame and exit. */
(void) sbrk(-frame_size);
return -1;
}
static void do_exec(int proc_e, char *exec, size_t exec_len, char *progname,
char *frame, int frame_len)
{
int r;
int hdrlen, sep_id, load_text, allow_setuid;
int need_restart, error;
vir_bytes stack_top, vsp;
vir_bytes text_bytes, data_bytes, bss_bytes, pc;
phys_bytes tot_bytes;
off_t off;
uid_t new_uid;
gid_t new_gid;
need_restart= 0;
error= 0;
self_e = getnprocnr(getpid());
/* Read the file header and extract the segment sizes. */
r = read_header(exec, exec_len, &sep_id,
&text_bytes, &data_bytes, &bss_bytes,
&tot_bytes, &pc, &hdrlen);
if (r != OK)
{
printf("do_exec: read_header failed\n");
goto fail;
}
need_restart= 1;
new_uid= getuid();
new_gid= getgid();
/* XXX what should we use to identify the executable? */
r= exec_newmem(proc_e, text_bytes, data_bytes, bss_bytes, tot_bytes,
frame_len, sep_id, 0 /*dev*/, proc_e /*inum*/, 0 /*ctime*/,
progname, new_uid, new_gid, &stack_top, &load_text,
&allow_setuid);
if (r != OK)
{
printf("do_exec: exec_newmap failed: %d\n", r);
error= r;
goto fail;
}
/* Patch up stack and copy it from FS to new core image. */
vsp = stack_top;
vsp -= frame_len;
patch_ptr(frame, vsp);
r = sys_datacopy(SELF, (vir_bytes) frame,
proc_e, (vir_bytes) vsp, (phys_bytes)frame_len);
if (r != OK) panic(__FILE__,"pm_exec stack copy err on", proc_e);
off = hdrlen;
/* Read in text and data segments. */
if (load_text) {
r= read_seg(exec, exec_len, off, proc_e, T, text_bytes);
if (r != OK)
{
printf("do_exec: read_seg failed: %d\n", r);
error= r;
goto fail;
}
}
else
printf("do_exec: not loading text segment\n");
off += text_bytes;
r= read_seg(exec, exec_len, off, proc_e, D, data_bytes);
if (r != OK)
{
printf("do_exec: read_seg failed: %d\n", r);
error= r;
goto fail;
}
exec_restart(proc_e, OK);
return;
fail:
printf("do_exec(fail): error = %d\n", error);
if (need_restart)
exec_restart(proc_e, error);
}
/*===========================================================================*
* exec_newmem *
*===========================================================================*/
PRIVATE int exec_newmem(proc_e, text_bytes, data_bytes, bss_bytes, tot_bytes,
frame_len, sep_id, st_dev, st_ino, st_ctime, progname,
new_uid, new_gid, stack_topp, load_textp, allow_setuidp)
int proc_e;
vir_bytes text_bytes;
vir_bytes data_bytes;
vir_bytes bss_bytes;
vir_bytes tot_bytes;
vir_bytes frame_len;
int sep_id;
dev_t st_dev;
ino_t st_ino;
time_t st_ctime;
int new_uid;
int new_gid;
char *progname;
vir_bytes *stack_topp;
int *load_textp;
int *allow_setuidp;
{
int r;
struct exec_newmem e;
message m;
e.text_bytes= text_bytes;
e.data_bytes= data_bytes;
e.bss_bytes= bss_bytes;
e.tot_bytes= tot_bytes;
e.args_bytes= frame_len;
e.sep_id= sep_id;
e.st_dev= st_dev;
e.st_ino= st_ino;
e.st_ctime= st_ctime;
e.new_uid= new_uid;
e.new_gid= new_gid;
strncpy(e.progname, progname, sizeof(e.progname)-1);
e.progname[sizeof(e.progname)-1]= '\0';
m.m_type= EXEC_NEWMEM;
m.EXC_NM_PROC= proc_e;
m.EXC_NM_PTR= (char *)&e;
r= sendrec(PM_PROC_NR, &m);
if (r != OK)
return r;
#if 0
printf("exec_newmem: r = %d, m_type = %d\n", r, m.m_type);
#endif
*stack_topp= m.m1_i1;
*load_textp= !!(m.m1_i2 & EXC_NM_RF_LOAD_TEXT);
*allow_setuidp= !!(m.m1_i2 & EXC_NM_RF_ALLOW_SETUID);
#if 0
printf("exec_newmem: stack_top = 0x%x\n", *stack_topp);
printf("exec_newmem: load_text = %d\n", *load_textp);
#endif
return m.m_type;
}
/*===========================================================================*
* exec_restart *
*===========================================================================*/
PRIVATE int exec_restart(proc_e, result)
int proc_e;
int result;
{
int r;
message m;
m.m_type= EXEC_RESTART;
m.EXC_RS_PROC= proc_e;
m.EXC_RS_RESULT= result;
r= sendrec(PM_PROC_NR, &m);
if (r != OK)
return r;
return m.m_type;
}
/*===========================================================================*
* read_header *
*===========================================================================*/
PRIVATE int read_header(exec, exec_len, sep_id, text_bytes, data_bytes,
bss_bytes, tot_bytes, pc, hdrlenp)
char *exec; /* executable image */
size_t exec_len; /* size of the image */
int *sep_id; /* true iff sep I&D */
vir_bytes *text_bytes; /* place to return text size */
vir_bytes *data_bytes; /* place to return initialized data size */
vir_bytes *bss_bytes; /* place to return bss size */
phys_bytes *tot_bytes; /* place to return total size */
vir_bytes *pc; /* program entry point (initial PC) */
int *hdrlenp;
{
/* Read the header and extract the text, data, bss and total sizes from it. */
off_t pos;
block_t b;
struct exec hdr; /* a.out header is read in here */
/* Read the header and check the magic number. The standard MINIX header
* is defined in <a.out.h>. It consists of 8 chars followed by 6 longs.
* Then come 4 more longs that are not used here.
* Byte 0: magic number 0x01
* Byte 1: magic number 0x03
* Byte 2: normal = 0x10 (not checked, 0 is OK), separate I/D = 0x20
* Byte 3: CPU type, Intel 16 bit = 0x04, Intel 32 bit = 0x10,
* Motorola = 0x0B, Sun SPARC = 0x17
* Byte 4: Header length = 0x20
* Bytes 5-7 are not used.
*
* Now come the 6 longs
* Bytes 8-11: size of text segments in bytes
* Bytes 12-15: size of initialized data segment in bytes
* Bytes 16-19: size of bss in bytes
* Bytes 20-23: program entry point
* Bytes 24-27: total memory allocated to program (text, data + stack)
* Bytes 28-31: size of symbol table in bytes
* The longs are represented in a machine dependent order,
* little-endian on the 8088, big-endian on the 68000.
* The header is followed directly by the text and data segments, and the
* symbol table (if any). The sizes are given in the header. Only the
* text and data segments are copied into memory by exec. The header is
* used here only. The symbol table is for the benefit of a debugger and
* is ignored here.
*/
int r;
pos= 0; /* Read from the start of the file */
if (exec_len < sizeof(hdr)) return(ENOEXEC);
memcpy(&hdr, exec, sizeof(hdr));
/* Check magic number, cpu type, and flags. */
if (BADMAG(hdr)) return(ENOEXEC);
#if (CHIP == INTEL && _WORD_SIZE == 2)
if (hdr.a_cpu != A_I8086) return(ENOEXEC);
#endif
#if (CHIP == INTEL && _WORD_SIZE == 4)
if (hdr.a_cpu != A_I80386) return(ENOEXEC);
#endif
if ((hdr.a_flags & ~(A_NSYM | A_EXEC | A_SEP)) != 0) return(ENOEXEC);
*sep_id = !!(hdr.a_flags & A_SEP); /* separate I & D or not */
/* Get text and data sizes. */
*text_bytes = (vir_bytes) hdr.a_text; /* text size in bytes */
*data_bytes = (vir_bytes) hdr.a_data; /* data size in bytes */
*bss_bytes = (vir_bytes) hdr.a_bss; /* bss size in bytes */
*tot_bytes = hdr.a_total; /* total bytes to allocate for prog */
if (*tot_bytes == 0) return(ENOEXEC);
if (!*sep_id) {
/* If I & D space is not separated, it is all considered data. Text=0*/
*data_bytes += *text_bytes;
*text_bytes = 0;
}
*pc = hdr.a_entry; /* initial address to start execution */
*hdrlenp = hdr.a_hdrlen & BYTE; /* header length */
return(OK);
}
/*===========================================================================*
* patch_ptr *
*===========================================================================*/
PRIVATE void patch_ptr(stack, base)
char stack[ARG_MAX]; /* pointer to stack image within PM */
vir_bytes base; /* virtual address of stack base inside user */
{
/* When doing an exec(name, argv, envp) call, the user builds up a stack
* image with arg and env pointers relative to the start of the stack. Now
* these pointers must be relocated, since the stack is not positioned at
* address 0 in the user's address space.
*/
char **ap, flag;
vir_bytes v;
flag = 0; /* counts number of 0-pointers seen */
ap = (char **) stack; /* points initially to 'nargs' */
ap++; /* now points to argv[0] */
while (flag < 2) {
if (ap >= (char **) &stack[ARG_MAX]) return; /* too bad */
if (*ap != NULL) {
v = (vir_bytes) *ap; /* v is relative pointer */
v += base; /* relocate it */
*ap = (char *) v; /* put it back */
} else {
flag++;
}
ap++;
}
}
/*===========================================================================*
* read_seg *
*===========================================================================*/
PRIVATE int read_seg(exec, exec_len, off, proc_e, seg, seg_bytes)
char *exec; /* executable image */
size_t exec_len; /* size of the image */
off_t off; /* offset in file */
int proc_e; /* process number (endpoint) */
int seg; /* T, D, or S */
phys_bytes seg_bytes; /* how much is to be transferred? */
{
/*
* The byte count on read is usually smaller than the segment count, because
* a segment is padded out to a click multiple, and the data segment is only
* partially initialized.
*/
int r;
off_t n, o, b_off, seg_off;
if (off+seg_bytes > exec_len) return ENOEXEC;
r= sys_vircopy(SELF, D, (vir_bytes)exec+off, proc_e, seg, 0, seg_bytes);
return r;
}

View file

@ -81,7 +81,8 @@ PUBLIC int main(void)
*/
else {
switch(call_nr) {
case RS_UP: result = do_up(&m); break;
case RS_UP: result = do_up(&m, FALSE /*!do_copy*/); break;
case RS_UP_COPY: result = do_up(&m, TRUE /*do_copy*/); break;
case RS_DOWN: result = do_down(&m); break;
case RS_REFRESH: result = do_refresh(&m); break;
case RS_RESCUE: result = do_rescue(&m); break;
@ -127,6 +128,7 @@ PRIVATE void init_server(void)
if ((s = getsysinfo(FS_PROC_NR, SI_DMAP_TAB, dmap)) < 0)
panic("RS","warning: couldn't get copy of dmap table", errno);
#if 0
/* Now initialize the table with the processes in the system image.
* Prepend /sbin/ to the binaries so that we can actually find them.
*/
@ -147,6 +149,7 @@ PRIVATE void init_server(void)
rproc[s].r_argv[1] = NULL;
}
}
#endif
/* Set alarm to periodically check driver status. */
if (OK != (s=sys_setalarm(RS_DELTA_T, 0)))

View file

@ -4,11 +4,14 @@
*/
#include "inc.h"
#include <fcntl.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/wait.h>
#include <minix/dmap.h>
#include <minix/endpoint.h>
#include <lib.h>
/* Allocate variables. */
struct rproc rproc[NR_SYS_PROCS]; /* system process table */
@ -19,6 +22,8 @@ extern int errno; /* error status */
/* Prototypes for internal functions that do the hard work. */
FORWARD _PROTOTYPE( int start_service, (struct rproc *rp) );
FORWARD _PROTOTYPE( int stop_service, (struct rproc *rp,int how) );
FORWARD _PROTOTYPE( int fork_nb, (void) );
FORWARD _PROTOTYPE( int read_exec, (struct rproc *rp) );
PRIVATE int shutting_down = FALSE;
@ -27,8 +32,9 @@ PRIVATE int shutting_down = FALSE;
/*===========================================================================*
* do_up *
*===========================================================================*/
PUBLIC int do_up(m_ptr)
PUBLIC int do_up(m_ptr, do_copy)
message *m_ptr; /* request message pointer */
int do_copy; /* keep copy in memory */
{
/* A request was made to start a new system service. Dismember the request
* message and gather all information needed to start the service. Starting
@ -78,6 +84,14 @@ message *m_ptr; /* request message pointer */
rp->r_argv[arg_count] = NULL; /* end with NULL pointer */
rp->r_argc = arg_count;
rp->r_exec= NULL;
if (do_copy)
{
s= read_exec(rp);
if (s != OK)
return s;
}
/* Initialize some fields. */
rp->r_period = m_ptr->RS_PERIOD;
rp->r_dev_nr = m_ptr->RS_DEV_MAJOR;
@ -192,7 +206,7 @@ PUBLIC void do_exit(message *m_ptr)
while ( (exit_pid = waitpid(-1, &exit_status, WNOHANG)) != 0 ) {
#if VERBOSE
printf("RS: proc %d, pid %d, ", rp->r_proc_nr_e, exit_pid);
printf("RS: pid %d, ", exit_pid);
if (WIFSIGNALED(exit_status)) {
printf("killed, signal number %d\n", WTERMSIG(exit_status));
}
@ -213,6 +227,11 @@ PUBLIC void do_exit(message *m_ptr)
if ((rp->r_flags & RS_EXITING) || shutting_down) {
rp->r_flags = 0; /* release slot */
if (rp->r_exec)
{
free(rp->r_exec);
rp->r_exec= NULL;
}
rproc_ptr[proc] = NULL;
}
else if(rp->r_flags & RS_REFRESHING) {
@ -231,6 +250,9 @@ PUBLIC void do_exit(message *m_ptr)
* exit, immediately restart this service. Otherwise use
* a binary exponetial backoff.
*/
#if 0
rp->r_restarts= 0;
#endif
if (rp->r_restarts > 0) {
rp->r_backoff = 1 << MIN(rp->r_restarts,(BACKOFF_BITS-1));
rp->r_backoff = MIN(rp->r_backoff,MAX_BACKOFF);
@ -331,11 +353,17 @@ struct rproc *rp;
int child_proc_nr_e, child_proc_nr_n; /* child process slot */
pid_t child_pid; /* child's process id */
char *file_only;
int s;
int s, use_copy;
message m;
use_copy= (rp->r_exec != NULL);
/* Now fork and branch for parent and child process (and check for error). */
child_pid = fork();
if (use_copy)
child_pid= fork_nb();
else
child_pid = fork();
switch(child_pid) { /* see fork(2) */
case -1: /* fork failed */
report("RS", "warning, fork() failed", errno); /* shouldn't happen */
@ -346,9 +374,12 @@ struct rproc *rp;
* e.g., because the root file system cannot be read, try to strip of
* the path, and see if the command is in RS' current working dir.
*/
execve(rp->r_argv[0], rp->r_argv, NULL); /* POSIX execute */
file_only = strrchr(rp->r_argv[0], '/') + 1;
execve(file_only, rp->r_argv, NULL); /* POSIX execute */
if (!use_copy)
{
execve(rp->r_argv[0], rp->r_argv, NULL); /* POSIX execute */
file_only = strrchr(rp->r_argv[0], '/') + 1;
execve(file_only, rp->r_argv, NULL); /* POSIX execute */
}
printf("RS: exec failed for %s: %d\n", rp->r_argv[0], errno);
exit(EXEC_FAILED); /* terminate child */
@ -357,12 +388,27 @@ struct rproc *rp;
break; /* continue below */
}
/* Only the parent process (the RS server) gets to this point. The child
* is still inhibited from running because it's privilege structure is
* not yet set. First try to set the device driver mapping at the FS.
if (use_copy)
{
extern char **environ;
dev_execve(child_proc_nr_e, rp->r_exec, rp->r_exec_len, rp->r_argv,
environ);
}
/* Set the privilege structure for the child process to let is run.
* This should succeed: we tested number in use above.
*/
if ((s = sys_privctl(child_proc_nr_e, SYS_PRIV_INIT, 0, NULL)) < 0) {
report("RS","sys_privctl call failed", s); /* to let child run */
rp->r_flags |= RS_EXITING; /* expect exit */
if(child_pid > 0) kill(child_pid, SIGKILL); /* kill driver */
else report("RS", "didn't kill pid", child_pid);
return(s); /* return error */
}
if (rp->r_dev_nr > 0) { /* set driver map */
if ((s=mapdriver(child_proc_nr_e, rp->r_dev_nr, rp->r_dev_style)) < 0) {
if ((s=mapdriver(child_proc_nr_e, rp->r_dev_nr, rp->r_dev_style,
!!use_copy /* force */)) < 0) {
report("RS", "couldn't map driver", errno);
rp->r_flags |= RS_EXITING; /* expect exit */
if(child_pid > 0) kill(child_pid, SIGKILL); /* kill driver */
@ -371,18 +417,6 @@ struct rproc *rp;
}
}
/* The device driver mapping has been set, or the service was not a driver.
* Now, set the privilege structure for the child process to let is run.
* This should succeed: we tested number in use above.
*/
if ((s = sys_privctl(child_proc_nr_e, SYS_PRIV_INIT, 0, NULL)) < 0) {
report("RS","call to SYSTEM failed", s); /* to let child run */
rp->r_flags |= RS_EXITING; /* expect exit */
if(child_pid > 0) kill(child_pid, SIGKILL); /* kill driver */
else report("RS", "didn't kill pid", child_pid);
return(s); /* return error */
}
#if VERBOSE
printf("RS: started '%s', major %d, pid %d, endpoint %d, proc %d\n",
rp->r_cmd, rp->r_dev_nr, child_pid,
@ -456,3 +490,52 @@ message *m_ptr;
return(OK);
}
PRIVATE pid_t fork_nb()
{
message m;
return(_syscall(PM_PROC_NR, FORK_NB, &m));
}
PRIVATE int read_exec(rp)
struct rproc *rp;
{
int e, r, fd;
char *e_name;
struct stat sb;
e_name= rp->r_argv[0];
r= stat(e_name, &sb);
if (r != 0)
return -errno;
fd= open(e_name, O_RDONLY);
if (fd == -1)
return -errno;
rp->r_exec_len= sb.st_size;
rp->r_exec= malloc(rp->r_exec_len);
if (rp->r_exec == NULL)
{
printf("read_exec: unable to allocate %d bytes\n",
rp->r_exec_len);
close(fd);
return ENOMEM;
}
r= read(fd, rp->r_exec, rp->r_exec_len);
e= errno;
close(fd);
if (r == rp->r_exec_len)
return OK;
printf("read_exec: read failed %d, errno %d\n", r, e);
free(rp->r_exec);
rp->r_exec= NULL;
if (r >= 0)
return EIO;
else
return -e;
}

View file

@ -26,6 +26,9 @@ extern struct rproc {
clock_t r_alive_tm; /* timestamp of last heartbeat */
clock_t r_stop_tm; /* timestamp of SIGTERM signal */
char *r_exec; /* Executable image */
size_t r_exec_len; /* Length of image */
char r_cmd[MAX_COMMAND_LEN]; /* raw command plus arguments */
char *r_argv[MAX_NR_ARGS+2]; /* parsed arguments vector */
int r_argc; /* number of arguments */

View file

@ -1,10 +1,14 @@
/* Function prototypes. */
/* exec.c */
_PROTOTYPE( int dev_execve, (int proc_e,
char *exec, size_t exec_len, char *argv[], char **env));
/* main.c */
_PROTOTYPE( int main, (void));
/* manager.c */
_PROTOTYPE( int do_up, (message *m));
_PROTOTYPE( int do_up, (message *m, int do_copy));
_PROTOTYPE( int do_down, (message *m));
_PROTOTYPE( int do_refresh, (message *m));
_PROTOTYPE( int do_rescue, (message *m));