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/************************************************************************
*
* exec.cpp - Definitions of the child process subsystem
*
* $Id$
*
************************************************************************
*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed
* with this work for additional information regarding copyright
* ownership. The ASF licenses this file to you under the Apache
* License, Version 2.0 (the "License"); you may not use this file
* except in compliance with the License. You may obtain a copy of
* the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
* implied. See the License for the specific language governing
* permissions and limitations under the License.
*
**************************************************************************/
/* disable Compaq/HP C++ pure libc headers to allow POSIX symbols
such as SIGALRM or SIGKILL to be defined. */
#undef __PURE_CNAME
#include <assert.h> /* for assert */
#include <ctype.h> /* for tolower */
#include <errno.h> /* for errno */
#include <fcntl.h> /* for O_*, */
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h> /* for str*, mem* */
#if !defined (_WIN32) && !defined (_WIN64)
# include <unistd.h> /* for close, dup, exec, fork */
# include <sys/wait.h>
# include <sys/times.h> /* for times - is this XSI? */
# ifdef _XOPEN_UNIX
# include <sys/resource.h> /* for setlimit(), RLIMIT_CORE, ... */
# endif
#else
# include <windows.h> /* for PROCESS_INFORMATION, ... */
# include <process.h> /* for CreateProcess, ... */
#endif
#include <sys/stat.h> /* for S_* */
#include <sys/types.h>
#include "cmdopt.h"
#include "target.h" /* For struct target_opts */
#include "util.h"
#include "exec.h"
/**
Status flag used to comunicate that an alarm has triggered.
Value is 0 when alarm hasn't been triggered or has been handled
Value is 1 when alarm has been triggered and hasn't been handled
@see handle_alrm
@see handle_term_signal
*/
static int alarm_timeout;
/**
Record of fatal signal recieved. Used to raise() the signal again after
child process has been killed.
@see handle_term_signal
*/
static int kill_signal;
/**
Utility macro to generate a signal number/name pair.
@parm val 'short' signal name (no leading SIG) to generate pair for.
@see signal_names []
*/
#undef SIGNAL
#define SIGNAL(val) { SIG ## val, #val }
/**
Signal name/number translation table.
This table is populated using the SIGNAL helper macro to translate
system SIG* macro values into name/value pairs.
@see SIGNAL ()
*/
static const struct {
int val; /**< Signal value for lookup pair */
const char* str; /**< Signal name for lookup pair */
} signal_names [] = {
#ifdef SIGABRT
SIGNAL (ABRT),
#endif /* SIGABRT */
#ifdef SIGALRM
SIGNAL (ALRM),
#endif /* SIGALRM */
#ifdef SIGBUS
SIGNAL (BUS),
#endif /* SIGBUS */
#ifdef SIGCANCEL
SIGNAL (CANCEL),
#endif /* SIGCANCEL */
#ifdef SIGCHLD
SIGNAL (CHLD),
#endif /* SIGCHLD */
#ifdef SIGCKPT
SIGNAL (CKPT),
#endif /* SIGCKPT */
#ifdef SIGCLD
SIGNAL (CLD),
#endif /* SIGCLD */
#ifdef SIGCONT
SIGNAL (CONT),
#endif /* SIGCONT */
#ifdef SIGDIL
SIGNAL (DIL),
#endif /* SIGDIL */
#ifdef SIGEMT
SIGNAL (EMT),
#endif /* SIGEMT */
#ifdef SIGFPE
SIGNAL (FPE),
#endif /* SIGFPE */
#ifdef SIGFREEZE
SIGNAL (FREEZE),
#endif /* SIGFREEZE */
#ifdef SIGGFAULT
SIGNAL (GFAULT),
#endif /* SIGGFAULT */
#ifdef SIGHUP
SIGNAL (HUP),
#endif /* SIGHUP */
#ifdef SIGILL
SIGNAL (ILL),
#endif /* SIGILL */
#ifdef SIGINFO
SIGNAL (INFO),
#endif /* SIGINFO */
#ifdef SIGINT
SIGNAL (INT),
#endif /* SIGINT */
#ifdef SIGIO
SIGNAL (IO),
#endif /* SIGIO */
#ifdef SIGIOT
SIGNAL (IOT),
#endif /* SIGIOT */
#ifdef SIGK32
SIGNAL (K32),
#endif /* SIGK32 */
#ifdef SIGKILL
SIGNAL (KILL),
#endif /* SIGKILL */
#ifdef SIGLOST
SIGNAL (LOST),
#endif /* SIGLOST */
#ifdef SIGLWP
SIGNAL (LWP),
#endif /* SIGLWP */
#ifdef SIGPIPE
SIGNAL (PIPE),
#endif /* SIGPIPE */
#ifdef SIGPOLL
SIGNAL (POLL),
#endif /* SIGPOLL */
#ifdef SIGPROF
SIGNAL (PROF),
#endif /* SIGPROF */
#ifdef SIGPTINTR
SIGNAL (PTINTR),
#endif /* SIGPTINTR */
#ifdef SIGPTRESCHED
SIGNAL (PTRESCHED),
#endif /* SIGPTRESCHED */
#ifdef SIGPWR
SIGNAL (PWR),
#endif /* SIGPWR */
#ifdef SIGQUIT
SIGNAL (QUIT),
#endif /* SIGQUIT */
#ifdef SIGRESTART
SIGNAL (RESTART),
#endif /* SIGRESTART */
#ifdef SIGRESV
SIGNAL (RESV),
#endif /* SIGRESV */
#ifdef SIGSEGV
SIGNAL (SEGV),
#endif /* SIGSEGV */
#ifdef SIGSTKFLT
SIGNAL (STKFLT),
#endif /* SIGSTKFLT */
#ifdef SIGSTOP
SIGNAL (STOP),
#endif /* SIGSTOP */
#ifdef SIGSYS
SIGNAL (SYS),
#endif /* SIGSYS */
#ifdef SIGTERM
SIGNAL (TERM),
#endif /* SIGTERM */
#ifdef SIGTHAW
SIGNAL (THAW),
#endif /* SIGTHAW */
#ifdef SIGTRAP
SIGNAL (TRAP),
#endif /* SIGTRAP */
#ifdef SIGTSTP
SIGNAL (TSTP),
#endif /* SIGTSTP */
#ifdef SIGTTIN
SIGNAL (TTIN),
#endif /* SIGTTIN */
#ifdef SIGTTOU
SIGNAL (TTOU),
#endif /* SIGTTOU */
#ifdef SIGUNUSED
SIGNAL (UNUSED),
#endif /* SIGUNUSED */
#ifdef SIGURG
SIGNAL (URG),
#endif /* SIGURG */
#ifdef SIGUSR1
SIGNAL (USR1),
#endif /* SIGUSR1 */
#ifdef SIGUSR2
SIGNAL (USR2),
#endif /* SIGUSR2 */
#ifdef SIGVTALRM
SIGNAL (VTALRM),
#endif /* SIGVTALRM */
#ifdef SIGWAITING
SIGNAL (WAITING),
#endif /* SIGWAITING */
#ifdef SIGWINCH
SIGNAL (WINCH),
#endif /* SIGWINCH */
#ifdef SIGWINDOW
SIGNAL (WINDOW),
#endif /* SIGWINDOW */
#ifdef SIGXCPU
SIGNAL (XCPU),
#endif /* SIGXCPU */
#ifdef SIGXFSZ
SIGNAL (XFSZ),
#endif /* SIGXFSZ */
#ifdef SIGXRES
SIGNAL (XRES),
#endif /* SIGXRES */
{ -1, 0 }
};
/**
Compare two characters in a case-insensitive manner
@param c1 first character to compare
@param c2 second character to compare
@return an integer less than, equal to, or greater than 0, coresponding
to whether c1 is less than, equal to, or greater than c2 when compared
in a case insensitive manner.
*/
static int
rw_charcasecmp (char c1, char c2)
{
typedef unsigned char UChar;
return tolower ((UChar)c1) - tolower ((UChar)c2);
}
/**
Reimplementation of the POSIX strcasecmp function.
This is a simplistic (re)implementation of the strcasecmp function
specified in the XSI extension to the IEEE Std 1003.1 (POSIX) standard.
@param s1 pointer to first string to compare
@param s2 pointer to second string to compare
@return an integer less than, equal to, or greater than 0, coresponding
to whether s1 is less than, equal to, or greater than s2 when compared
in a case insensitive manner.
*/
static int
rw_strcasecmp (const char* s1, const char* s2)
{
int delta;
assert (0 != s1);
assert (0 != s2);
for (delta = rw_charcasecmp (*s1, *s2);
*s1 && *s2 && 0 == delta;
delta = rw_charcasecmp (*(++s1), *(++s2)));
return delta;
}
int
get_signo (const char* signame)
{
size_t i;
typedef unsigned char UChar;
assert (0 != signame);
if (isdigit (signame [0])) {
char *junk;
int trans = strtol (signame, &junk, 10);
if (0 == *junk && 0 == errno)
return trans;
else
return -1;
}
if ( 's' == tolower ((UChar)signame [0])
&& 'i' == tolower ((UChar)signame [1])
&& 'g' == tolower ((UChar)signame [2]))
signame += 3;
for (i = 0; signal_names [i].str; ++i) {
if (0 == rw_strcasecmp (signal_names [i].str, signame)) {
return signal_names [i].val;
}
}
return -1;
}
const char*
get_signame (int signo)
{
size_t i;
static char def [32];
for (i = 0; signal_names [i].str; ++i) {
if (signal_names [i].val == signo) {
return signal_names [i].str;
}
}
/* We've run out of known signal numbers, so use a default name */
sprintf (def, "SIG#%d", signo);
return def;
}
#if !defined (_WIN32) && !defined (_WIN64)
/**
Callback used to set the alarm_timeout flag in response to recieving
the signal SIGALRM
@param signo the signal recieved (should be SIGALRM)
@see alarm_timeout
*/
#ifdef __cplusplus
extern "C" {
#endif
static void
handle_alrm (int signo)
{
if (SIGALRM == signo)
alarm_timeout = 1;
}
/**
Callback used to gracefully terminate the utility if signaled to do so
while running a target
@param signo the signal recieved (should be in {SIGHUP, SIGINT, SIGQUIT,
SIGTERM})
@see alarm_timeout
*/
static void
handle_term_signal (int signo)
{
kill_signal = signo;
alarm_timeout = 1;
}
typedef void (*alarm_handler)(int);
#ifdef __cplusplus
}
#endif
/**
Monitors child_pid and determines how/when terminated.
This method is built around a waitpid loop, which is responsible for
determining the status of child_pid. This loop breaks when we've detected
that the child process has terminated, or when we conclude it won't
terminate. To prevent the child process from running forever, we set
handle_alrm as the handler for SIGALRM using the sigaction system call and
set a timeout using the alarm () system call. If this timeout expires, we
try to kill the child process using several different signals.
@todo add better handling for corner conditions
@param child_pid process ID number for the child process to monitor
@return structure describing how the child procees exited
@see handle_alrm
@see alarm_timeout
*/
static void
wait_for_child (pid_t child_pid, int timeout, struct target_status* result)
{
/* note that processes with no controlling terminal ignore
the SIGINT and SIGQUIT signals
*/
static const int signals [] = {
SIGHUP, SIGINT, SIGQUIT, SIGTERM, SIGKILL, SIGKILL
};
static const unsigned sigcount = sizeof (signals) / sizeof (int);
struct sigaction act;
unsigned siginx = 0;
int stopped = 0;
#ifdef WCONTINUED
int waitopts = WUNTRACED | WCONTINUED;
#else
int waitopts = WUNTRACED;
#endif
int status;
assert (1 < child_pid);
/* Clear timeout */
alarm_timeout = 0;
/* Set handler (if needed). Need to use sigaction rather than signal due
to linux glitch
*/
memset (&act, 0, sizeof act);
/* avoid extern "C"/"C++" mismatch due to an HP aCC 6 bug
(see STDCXX-291)
*/
alarm_handler phandler = handle_alrm;
memcpy (&act.sa_handler, &phandler, sizeof act.sa_handler);
sigaction (SIGALRM, &act, 0);
/* Set handlers for SIGHUP, SIGINT, SIGQUIT, SIGTERM so we can kill the
child process prior to dieing.
*/
kill_signal = 0;
phandler = handle_term_signal;
memcpy (&act.sa_handler, &phandler, sizeof act.sa_handler);
sigaction (SIGHUP, &act, 0);
sigaction (SIGINT, &act, 0);
sigaction (SIGQUIT, &act, 0);
sigaction (SIGTERM, &act, 0);
if (timeout > 0)
alarm (timeout);
while (1) {
const pid_t wait_pid = waitpid (child_pid, &status, waitopts);
if (child_pid == wait_pid) {
if (WIFEXITED (status)) {
result->exit = WEXITSTATUS (status);
switch (result->exit) {
case 126:
result->status = ST_EXIST;
break;
case 127:
result->status = ST_EXECUTE;
break;
}
break; /*we've got an exit state, so let's bail*/
}
else if (WIFSIGNALED (status)) {
result->exit = WTERMSIG (status);
result->signaled = 1;
break; /*we've got an exit state, so let's bail*/
}
else if (WIFSTOPPED (status))
stopped = status;
#ifdef WIFCONTINUED /*Perhaps we should guard WIFSTOPPED with this guard also */
else if (WIFCONTINUED (status))
stopped = 0;
#endif
else
; /* huh? */
}
else if ((pid_t)-1 == wait_pid) {
if (EINTR == errno && alarm_timeout) {
/* timeout elapsed, so send a signal to the child */
if (stopped) {
/* If the child process is stopped, it is incapable of
recieving signals. Therefore, we'll record this
and break out of the loop.
*/
result->exit = WTERMSIG (stopped);
result->signaled = 1;
break;
}
if (0 != kill (-child_pid, signals [siginx])) {
if (ESRCH == errno)
/* ESRCH means 'No process (group) found'. Since
there aren't any processes in the process group,
we'll continue so we can collect the return value
if needed.
*/
continue;
/* In addition to ESRCH, kill () may also set errno to
EINVAL or EPERM, according to the POSIX spec, in
addition to any platform specific extensions.
EPERM means 'No permissions to signal any recieving
process'. It is unlikely that this situation will
change, but we will try the remaining signals in the
signals array, in the same manner as if the signal had
been sent correctly.
EINVAL means 'The signal is an invalid or unsupported
signal number'. As the signal number macros used in
the signal array are hard coded, issues should be
detected at compile time, not run time. This is not a
fatal situation, so the remainder of signals in the
signal array will be tried, as if this transmission
had been successfull.
The correct behavior for any platform-specific
extensions needs to be evaluated, but we are treating
them like EPERM or EINVAL at this time. */
}
/* Consider recording the signal used here.*/
++siginx;
/* Step to the next signal */
if (siginx >= sigcount) {
/* Still running, but we've run out of signals to try
Therefore, we'll set error flags and break out of
the loop.
*/
result->status = ST_NOT_KILLED;
break;
}
/* Reset the alarm */
alarm_timeout = 0;
alarm (1);
}
else if (EINTR == errno && !alarm_timeout) {
/* continue iterating */
}
else if (EINVAL == errno) {
if (waitopts)
/* bad waitpid options, reset to 0 and try again */
waitopts = 0;
else
; /* Now what? */
}
else if (ECHILD == errno) {
/* should not happen */
warn ("waitpid (%d) error: %s\n", (int)child_pid,
strerror (errno));
}
else {
/* waitpid () error */
warn ("waitpid (%d) error: %s\n", (int)child_pid,
strerror (errno));
}
}
else if ((pid_t)0 == wait_pid) {
/* should not happen */
}
else {
/* what the heck? */
}
}
/* Clear alarm */
alarm (0);
/* Kill/cleanup any grandchildren. */
/* On solaris, this logic tries to avoid the situation where grandchild
process times are rolled into the timing of a later process */
while (siginx < sigcount && 0 == kill (-child_pid, signals [siginx])) {
++siginx;
sleep (1);
}
/* Check if we were signaled to quit. */
if (kill_signal) {
/* Reset the handlers to normal */
act.sa_handler = SIG_DFL;
sigaction (SIGHUP, &act, 0);
sigaction (SIGINT, &act, 0);
sigaction (SIGQUIT, &act, 0);
sigaction (SIGTERM, &act, 0);
if (0 > raise (kill_signal))
terminate (1, "raise(%s) failed: %s\n",
get_signame (kill_signal), strerror (errno));
}
}
/**
Opens an input file, based on exec_name
Takes a data directory and an executable name, and tries to open an input
file based on these variables. If a file is found in neither of two
locattions derived from these variables, this method tries to fall back on
/dev/null.
Source file locations:
- [data_dir]/manual/in/[exec_name].in
- [data_dir]/tutorial/in/[exec_name].in
- /dev/null
@param data_dir the path of the reference data directory
@param exec_name the name of executable being run
@returns the file descriptor of the opened file
*/
static int
open_input (const char* data_dir, const char* exec_name)
{
int intermit = -1;
assert (0 != exec_name);
assert (0 != data_dir);
if (strlen (data_dir)) {
char* tmp_name;
/* Try data_dir/manual/in/exec_name.in */
tmp_name = reference_name (data_dir, "manual", "in");
intermit = open (tmp_name, O_RDONLY);
/* If we opened the file, return the descriptor */
if (0 <= intermit) {
free (tmp_name);
return intermit;
}
/* If the file exists (errno isn't ENOENT), exit */
if (ENOENT != errno)
terminate (1, "open (%s) failed: %s\n", tmp_name,
strerror (errno));
/* Try data_dir/tutorial/in/exec_name.in */
free (tmp_name);
tmp_name = reference_name (data_dir, "tutorial", "in");
intermit = open (tmp_name, O_RDONLY);
/* If we opened the file, return the descriptor */
if (0 <= intermit) {
free (tmp_name);
return intermit;
}
/* If the file exists (errno isn't ENOENT), exit */
if (-1 == intermit && ENOENT != errno)
terminate (1, "open (%s) failed: %s\n", tmp_name,
strerror (errno));
free (tmp_name);
}
/* If we didn't find a source file, open /dev/null */
intermit = open ("/dev/null", O_RDONLY);
/* If we opened the file, return the descriptor */
if (0 <= intermit)
return intermit;
/* otherwise, print an error message and exit */
terminate (1, "open (/dev/null) failed: %s\n", strerror (errno));
return -1; /* silence a compiler warning */
}
/**
Replaces one file descriptor with a second, closing second after replacing
the first.
@param source file descriptor to copy
@param dest file descriptor to replace
@param name human understanable name for dest, used in error messages
*/
static void
replace_file (int source, int dest, const char* name)
{
int result;
assert (source != dest);
assert (0 <= source);
assert (0 <= dest);
assert (0 != name);
result = dup2 (source, dest);
if (-1 == result)
terminate (1, "redirecting to %s failed: %s\n", name,
strerror (errno));
result = close (source);
if (-1 == result)
terminate (1, "closing source for %s redirection failed: %s\n",
name, strerror (errno));
}
#ifdef _XOPEN_UNIX
/**
Utility macro to generate an rlimit tuple.
@parm val 'short' resource name (no leading RLIMIT_).
@param idx rw_rlimit pointer in the target_opts structure
@see limit_process
@see target_opts
*/
#undef LIMIT
#define LIMIT(val, idx) { RLIMIT_ ## val, options->idx, #val }
/**
Set process resource limits, based on the child_limits global.
This method uses the LIMIT macro to build an internal array of limits to
try setting. If setrlimit fails, we print a warning message (into the
output file) and move on.
@param options structure containing limits to set.
*/
static void
limit_process (const struct target_opts* options)
{
static const struct {
int resource;
rw_rlimit* limit;
const char* name;
} limits[] = {
#ifdef RLIMIT_CORE
LIMIT (CORE, core),
#endif /* RLIMIT_CORE */
#ifdef RLIMIT_CPU
LIMIT (CPU, cpu),
#endif /* RLIMIT_CPU */
#ifdef RLIMIT_DATA
LIMIT (DATA, data),
#endif /* RLIMIT_DATA */
#ifdef RLIMIT_FSIZE
LIMIT (FSIZE, fsize),
#endif /* RLIMIT_FSIZE */
#ifdef RLIMIT_NOFILE
LIMIT (NOFILE, nofile),
#endif /* RLIMIT_NOFILE */
#ifdef RLIMIT_STACK
LIMIT (STACK, stack),
#endif /* RLIMIT_STACK */
#ifdef RLIMIT_AS
LIMIT (AS, as),
#endif /* RLIMIT_AS */
{ 0, 0, 0 }
};
for (size_t i = 0; limits [i].limit; ++i) {
struct rlimit local;
if (!limits [i].limit)
continue;
memcpy (&local, limits [i].limit, sizeof local);
if (setrlimit (limits [i].resource, &local)) {
warn ("error setting process limits for %s (soft: %lu, hard: "
"%lu): %s\n", limits [i].name, local.rlim_cur,
local.rlim_max, strerror (errno));
}
}
}
#endif /* _XOPEN_UNIX */
/**
Calculates the amount of resources used by the child processes.
This method uses the times() system call to calculate the resources used
by the child process. However, times() only is able to calcualte agragate
usage by all child processes, not usage by a specific child process.
Therefore, we must keep a running tally of how much resources had been used
the previous time we calculated the usage. This difference is the resources
that were used by the process that just completed.
@param result target_status structure to populate with process usage.
@param h_clk starting (wall clock) time
@param h_tms starting (system/user) time
*/
static void
calculate_usage (struct target_status* result, const clock_t h_clk,
const struct tms* const h_tms)
{
static clock_t wall, user, sys;
struct tms c_tms;
clock_t c_clk;
assert (0 != result);
assert (0 != h_tms);
wall = user = sys = 0;
c_clk = times (&c_tms);
if (-1 == c_clk) {
warn ("Failed to retrieve ending times: %s", strerror (errno));
return;
}
/* time calculations */
wall = c_clk - h_clk;
user = c_tms.tms_cutime - h_tms->tms_cutime;
sys = c_tms.tms_cstime - h_tms->tms_cstime;
/* Tag result as having run */
result->wall = &wall;
result->user = &user;
result->sys = &sys;
}
void exec_file (const struct target_opts* options, struct target_status* result)
{
const pid_t child_pid = fork ();
assert (0 != options);
assert (0 != options->argv);
assert (0 != options->argv [0]);
if (0 == child_pid) { /* child */
const char* const target_name = get_target ();
FILE* error_file;
assert (0 != target_name);
/* Set process group ID (so entire group can be killed)*/
{
const pid_t pgroup = setsid ();
if (getpid () != pgroup)
terminate (1, "Error setting process group: %s\n",
strerror (errno));
}
/* Cache stdout for use if execv () fails */
{
const int error_cache = dup (2);
if (-1 == error_cache)
terminate (1, "Error duplicating stderr: %s\n",
strerror (errno));
error_file = fdopen (error_cache,"a");
if (0 == error_file)
terminate (1, "Error opening file handle from cloned "
"stderr file descriptor: %s\n", strerror (errno));
}
/* Redirect stdin */
{
const int intermit = open_input (options->data_dir, target_name);
replace_file (intermit, 0, "stdin");
}
/* Redirect stdout */
{
char* const tmp_name = output_name (options->argv [0]);
int intermit;
intermit = open (tmp_name, O_WRONLY | O_CREAT | O_TRUNC,
S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH);
if (-1 == intermit)
terminate (1, "Error opening %s for output redirection: "
"%s\n", tmp_name, strerror (errno));
replace_file (intermit, 1, "stdout");
free (tmp_name);
}
/* Redirect stderr */
if (-1 == dup2 (1, 2))
terminate (1, "Redirection of stderr to stdout failed: %s\n",
strerror (errno));
#ifdef _XOPEN_UNIX
limit_process (options);
#endif /* _XOPEN_UNIX */
execv (options->argv [0], options->argv);
fprintf (error_file, "%s (%s): execv (\"%s\", ...) error: %s\n",
exe_name, target_name, options->argv [0], strerror (errno));
exit (1);
}
if (-1 == child_pid) {
result->status = ST_EXECUTE;
warn ("Unable to create child process for %s: %s\n", options->argv [0],
strerror (errno));
}
else {
/* parent */
struct tms h_tms;
clock_t h_clk = times (&h_tms);
wait_for_child (child_pid, options->timeout, result);
if (-1 != h_clk)
calculate_usage (result, h_clk, &h_tms);
else
warn ("Failed to retrieve start times: %s", strerror (errno));
}
}
#else /* _WIN{32,64} */
/**
Opens an input file, based on exec_name, using the child_sa security
setting.
Takes a data directory, an executable name and security setting, and tries
to open an input file based on these variables.
If a file is found in neither of two locations derived from these
variables, or if data_dir is a null string, it returns null.
If a file system error occurs when opening a file, INVALID_HANDLE_VALUE
is returned (and should be checked for).
Source file locations:
- [data_dir]/manual/in/[exec_name].in
- [data_dir]/tutorial/in/[exec_name].in
@param data_dir the path of the reference data directory
@param exec_name the name of executable being run
@param child_sa pointer to a SECURITY_ATTRIBUTES structure
@returns the file descriptor of the opened file
*/
static HANDLE
open_input (const char* data_dir, const char* exec_name,
SECURITY_ATTRIBUTES* child_sa)
{
HANDLE intermit;
DWORD error;
char* tmp_name;
assert (0 != exec_name);
assert (0 != data_dir);
assert (0 != child_sa);
if (!strlen (data_dir))
return 0;
/* Try data_dir\manual\in\exec_name.in */
tmp_name = reference_name (data_dir, "manual", "in");
intermit = CreateFile (tmp_name, GENERIC_READ, FILE_SHARE_READ, child_sa,
OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, NULL);
error = GetLastError ();
/* If we found the file, return the descriptor */
if (INVALID_HANDLE_VALUE != intermit || (2 != error && 3 != error)) {
free (tmp_name);
return intermit;
}
/* Try data_dir\tutorial\in\exec_name.in */
free (tmp_name);
tmp_name = reference_name (data_dir, "tutorial", "in");
intermit = CreateFile (tmp_name, GENERIC_READ, FILE_SHARE_READ, child_sa,
OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, NULL);
/* If we didn't find the file, null out the handle to return */
error = GetLastError ();
if (INVALID_HANDLE_VALUE == intermit && (2 == error || 3 == error)) {
intermit = 0;
}
free (tmp_name);
return intermit;
}
/**
Convert an argv array into a string that can be passed to CreateProcess.
This method allocates memory which the caller is responsible for free ()ing.
The provided argv array is converted into a series of quoted strings.
@param argv argv array to convert
@return allocated array with converted contents
*/
static char*
merge_argv (char** argv)
{
size_t len = 0;
char** opts;
char* term;
char* merge;
char* pos;
assert (0 != argv);
for (opts = argv; *opts; ++opts) {
len += 3; /* for open ", close " and trailing space or null */
for (term = *opts; *term; ++term) {
if ('"' == *term || escape_code == *term)
++len; /* Escape embedded "s and ^s*/
++len;
}
}
pos = merge = (char*)RW_MALLOC (len);
for (opts = argv; *opts; ++opts) {
*(pos++) = '"';
for (term = *opts; *term; ++term) {
if ('"' == *term || escape_code == *term)
*(pos++) = escape_code; /* Escape embedded "s and ^s*/
*(pos++) = *term;
}
*(pos++) = '"';
*(pos++) = ' ';
}
*(pos-1) = '\0'; /* convert trailing space to null */
return merge;
}
/**
Wrapper function around warn for windows native API calls.
@param action Human understandable description of failed action.
@return Value of GetLastError.
*/
static DWORD
warn_last_error (const char* action)
{
DWORD error = GetLastError ();
if (error) {
LPTSTR error_text = 0;
if (FormatMessage (FORMAT_MESSAGE_ALLOCATE_BUFFER |
FORMAT_MESSAGE_FROM_SYSTEM, NULL, error,
MAKELANGID (LANG_NEUTRAL, SUBLANG_DEFAULT),
(LPTSTR)&error_text, 0, NULL)) {
warn ("%s failed with error %d: %s\n", action, error, error_text);
LocalFree (error_text);
}
else {
warn ("%s failed with error %d. Additionally, FormatMessage "
"failed with error %d.\n", action, error, GetLastError ());
}
}
return error;
}
/**
Try killing the child process with what (limited) facilities we have at
our disposal. Does not collect exit code or close child process handle.
@param process Process handle of process to kill.
@param result status structure to record system errors in.
*/
static void
kill_child_process (PROCESS_INFORMATION child, struct target_status* result)
{
OSVERSIONINFO OSVer;
OSVer.dwOSVersionInfoSize = sizeof (OSVERSIONINFO);
if (0 == GetVersionEx (&OSVer)) {
result->status = ST_SYSTEM_ERROR;
warn_last_error ("Retrieving host version");
return;
}
/* Try to soft kill child process group if it didn't terminate, but only
on NT */
if (VER_PLATFORM_WIN32_NT == OSVer.dwPlatformId) {
struct sig_event
{
DWORD signal_;
const char* msg_;
}
sig_events [] = {
{ CTRL_C_EVENT, "Sending child process Control-C" },
{ CTRL_BREAK_EVENT, "Sending child process Control-Break" }
};
for (unsigned long i = 0;
i < sizeof (sig_events) / sizeof (*sig_events); ++i) {
DWORD wait_code;
if (0 == GenerateConsoleCtrlEvent (sig_events [i].signal_,
child.dwProcessId))
warn_last_error (sig_events [i].msg_);
wait_code = WaitForSingleObject (child.hProcess, 1000);
if (WAIT_TIMEOUT == wait_code)
continue;
if (WAIT_OBJECT_0 != wait_code) {
result->status = ST_SYSTEM_ERROR;
warn_last_error ("Waiting for child process");
}
return;
}
}
/* Then hard kill the child process */
if (0 == TerminateProcess (child.hProcess, 3))
warn_last_error ("Terminating child process");
else if (WAIT_FAILED == WaitForSingleObject (child.hProcess, 1000))
warn_last_error ("Waiting for child process");
}
void exec_file (const struct target_opts* options, struct target_status* result)
{
char* merged;
PROCESS_INFORMATION child;
STARTUPINFO context;
SECURITY_ATTRIBUTES child_sa = /* SA for inheritable handle. */
{sizeof (SECURITY_ATTRIBUTES), NULL, TRUE};
DWORD real_timeout, wait_code;
FILETIME start, end;
static clock_t wall;
assert (0 != options);
assert (0 != options->argv);
assert (0 != options->argv [0]);
real_timeout = (options->timeout > 0) ? options->timeout * 1000 : INFINITE;
/* Borrow our startup info */
GetStartupInfo (&context);
context.dwFlags = STARTF_USESTDHANDLES;
/* Create I/O handles */
{
/* Output redirection */
char* const tmp_name = output_name (options->argv [0]);
context.hStdOutput = CreateFile (tmp_name, GENERIC_WRITE,
FILE_SHARE_WRITE, &child_sa, CREATE_ALWAYS,
FILE_ATTRIBUTE_NORMAL, NULL);
if (INVALID_HANDLE_VALUE == context.hStdOutput) {
result->status = ST_SYSTEM_ERROR;
warn_last_error ("Opening child output stream");
return;
}
context.hStdError = context.hStdOutput;
free (tmp_name);
/* Input redirection */
context.hStdInput = open_input (options->data_dir, get_target (),
&child_sa);
if (INVALID_HANDLE_VALUE == context.hStdInput) {
CloseHandle (context.hStdOutput);
result->status = ST_SYSTEM_ERROR;
warn_last_error ("Opening child input stream");
return;
}
}
merged = merge_argv (options->argv);
/* set appropriate error mode (the child process inherits this
error mode) to disable displaying the critical-error-handler
and general-protection-fault message boxes */
UINT old_mode = SetErrorMode (SEM_FAILCRITICALERRORS
| SEM_NOGPFAULTERRORBOX);
/* Check the wall clock before creating the process */
GetSystemTimeAsFileTime(&start);
/* Create the child process */
if (0 == CreateProcess (options->argv [0], merged, 0, 0, 1,
CREATE_NEW_PROCESS_GROUP, 0, 0, &context, &child)) {
/* record the status if we failed to create the process */
result->status = ST_SYSTEM_ERROR;
warn_last_error ("Creating child process");;
}
/* restore the previous error mode */
SetErrorMode (old_mode);
/* Clean up handles */
if (context.hStdInput)
if (0 == CloseHandle (context.hStdInput))
warn_last_error ("Closing child input stream");
if (0 == CloseHandle (context.hStdOutput))
warn_last_error ("Closing child output stream");
/* Clean up argument string*/
free (merged);
/* Return if we failed to create the child process */
if (ST_SYSTEM_ERROR == result->status)
return;
if (0 == CloseHandle (child.hThread))
warn_last_error ("Closing child main thread handle");
/* Wait for the child process to terminate */
wait_code = WaitForSingleObject (child.hProcess, real_timeout);
switch (wait_code) {
case WAIT_OBJECT_0:
break;
case WAIT_TIMEOUT:
/* Child process didn't shut down, so note that we killed it. */
result->status = ST_KILLED;
kill_child_process (child, result);
break;
default:
result->status = ST_SYSTEM_ERROR;
warn_last_error ("Waiting for child process");
}
/* Calculate wall clock time elapsed while the process ran */
GetSystemTimeAsFileTime(&end);
/* We're ignoring dwHighDateTime, as it's outside the percision of clock_t
*/
wall = end.dwLowDateTime - start.dwLowDateTime;
/* Link the delta */
result->wall = &wall;
if (0 == GetExitCodeProcess (child.hProcess, (LPDWORD)&result->exit)) {
warn_last_error ("Retrieving child process exit code");
result->status = ST_SYSTEM_ERROR;
}
if (0 == CloseHandle (child.hProcess))
warn_last_error ("Closing child process handle");
if (STATUS_ACCESS_VIOLATION == result->exit) {
result->exit = SIGSEGV;
result->signaled = 1;
}
}
#endif /* _WIN{32,64} */