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#include "T.h"
#include <string.h>
#include <stdlib.h>
#include <unistd.h>
#include <pthread.h>
#include <stdio.h>
#include <sys/mman.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <sys/socket.h>
#include "common/config/config_userapi.h"
#define QUIT(x) do { \
printf("T tracer: QUIT: %s\n", x); \
exit(1); \
} while (0)
/* array used to activate/disactivate a log */
static int T_IDs[T_NUMBER_OF_IDS];
int *T_active = T_IDs;
int T_stdout = 1;
static int T_socket;
/* T_cache
* - the T macro picks up the head of freelist and marks it busy
* - the T sender thread periodically wakes up and sends what's to be sent
*/
volatile int _T_freelist_head;
volatile int *T_freelist_head = &_T_freelist_head;
T_cache_t *T_cache;
#if BASIC_SIMULATOR
/* global variables used by T_GET_SLOT, see in T.h */
volatile uint64_t T_next_id;
volatile uint64_t T_active_id;
#endif
static void get_message(int s) {
char t;
int l;
int id;
int is_on;
if (read(s, &t, 1) != 1) QUIT("get_message fails");
printf("T tracer: got mess %d\n", t);
switch (t) {
case 0:
/* toggle all those IDs */
/* optimze? (too much syscalls) */
if (read(s, &l, sizeof(int)) != sizeof(int)) QUIT("get_message fails");
while (l) {
if (read(s, &id, sizeof(int)) != sizeof(int)) QUIT("get_message fails");
T_IDs[id] = 1 - T_IDs[id];
l--;
}
break;
case 1:
/* set IDs as given */
/* optimize? */
if (read(s, &l, sizeof(int)) != sizeof(int)) QUIT("get_message fails");
id = 0;
while (l) {
if (read(s, &is_on, sizeof(int)) != sizeof(int))
QUIT("get_message fails");
T_IDs[id] = is_on;
id++;
l--;
}
break;
case 2:
break; /* do nothing, this message is to wait for local tracer */
}
}
static void *T_receive_thread(void *_) {
while (1) get_message(T_socket);
return NULL;
}
static void new_thread(void *(*f)(void *), void *data) {
pthread_t t;
pthread_attr_t att;
if (pthread_attr_init(&att)) {
fprintf(stderr, "pthread_attr_init err\n");
exit(1);
}
if (pthread_attr_setdetachstate(&att, PTHREAD_CREATE_DETACHED)) {
fprintf(stderr, "pthread_attr_setdetachstate err\n");
exit(1);
}
if (pthread_create(&t, &att, f, data)) {
fprintf(stderr, "pthread_create err\n");
exit(1);
}
if (pthread_attr_destroy(&att)) {
fprintf(stderr, "pthread_attr_destroy err\n");
exit(1);
}
}
/* defined in local_tracer.c */
void T_local_tracer_main(int remote_port, int wait_for_tracer,
int local_socket, void *shm_array);
/* We monitor the tracee and the local tracer processes.
* When one dies we forcefully kill the other.
*/
#include <sys/types.h>
#include <sys/wait.h>
static void monitor_and_kill(int child1, int child2) {
int child;
int status;
child = wait(&status);
if (child == -1) perror("wait");
kill(child1, SIGKILL);
kill(child2, SIGKILL);
exit(0);
}
void T_init(int remote_port, int wait_for_tracer, int dont_fork) {
int socket_pair[2];
int s;
int child1, child2;
int i;
if (socketpair(AF_UNIX, SOCK_STREAM, 0, socket_pair)) {
perror("socketpair");
abort();
}
/* setup shared memory */
T_cache = mmap(NULL, T_CACHE_SIZE * sizeof(T_cache_t),
PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, -1, 0);
if (T_cache == MAP_FAILED) {
perror("mmap");
abort();
}
/* let's garbage the memory to catch some potential problems
* (think multiprocessor sync issues, barriers, etc.)
*/
memset(T_cache, 0x55, T_CACHE_SIZE * sizeof(T_cache_t));
for (i = 0; i < T_CACHE_SIZE; i++) T_cache[i].busy = 0;
/* child1 runs the local tracer and child2 (or main) runs the tracee */
child1 = fork();
if (child1 == -1) abort();
if (child1 == 0) {
close(socket_pair[1]);
T_local_tracer_main(remote_port, wait_for_tracer, socket_pair[0],
T_cache);
exit(0);
}
close(socket_pair[0]);
if (dont_fork == 0) {
child2 = fork();
if (child2 == -1) abort();
if (child2 != 0) {
close(socket_pair[1]);
munmap(T_cache, T_CACHE_SIZE * sizeof(T_cache_t));
monitor_and_kill(child1, child2);
}
}
s = socket_pair[1];
/* wait for first message - initial list of active T events */
get_message(s);
T_socket = s;
new_thread(T_receive_thread, NULL);
}
void T_Config_Init(void) {
int T_port=TTRACER_DEFAULT_PORTNUM; /* by default we wait for the tracer */
int T_nowait=0; /* default port to listen to to wait for the tracer */
int T_dont_fork=0; /* default is to fork, see 'T_init' to understand */
paramdef_t ttraceparams[] = CMDLINE_TTRACEPARAMS_DESC;
/* for a cleaner config file, TTracer params should be defined in a
* specific section...
*/
config_get(ttraceparams,
sizeof(ttraceparams) / sizeof(paramdef_t),
TTRACER_CONFIG_PREFIX);
/* compatibility: look for TTracer command line options in root section */
config_process_cmdline(ttraceparams,
sizeof(ttraceparams) / sizeof(paramdef_t),
NULL);
if (T_stdout == 0)
T_init(T_port, 1-T_nowait, T_dont_fork);
}