#include <getopt.h>
#include "ustd.h"
-#include "localerr.h"
+#include "usterr.h"
#include "ustcomm.h"
/* return value: 0 = subbuffer is finished, it won't produce data anymore
#define PUT_SUBBUF_OK 1
#define PUT_SUBBUF_DIED 0
#define PUT_SUBBUF_PUSHED 2
+#define PUT_SUBBUF_DONE 3
char *sock_path=NULL;
char *trace_path=NULL;
+int daemon_mode = 0;
+char *pidfile = NULL;
/* Number of active buffers and the mutex to protect it. */
int active_buffers = 0;
/* Whether a request to end the program was received. */
sig_atomic_t terminate_req = 0;
-int test_sigpipe(void)
-{
- sigset_t sigset;
- int result;
-
- result = sigemptyset(&sigset);
- if(result == -1) {
- PERROR("sigemptyset");
- return -1;
- }
- result = sigaddset(&sigset, SIGPIPE);
- if(result == -1) {
- PERROR("sigaddset");
- return -1;
- }
-
- result = sigtimedwait(&sigset, NULL, &(struct timespec){0,0});
- if(result == -1 && errno == EAGAIN) {
- /* no signal received */
- return 0;
- }
- else if(result == -1) {
- PERROR("sigtimedwait");
- return -1;
- }
- else if(result == SIGPIPE) {
- /* received sigpipe */
- return 1;
- }
- else {
- assert(0);
- }
-}
-
int get_subbuffer(struct buffer_info *buf)
{
char *send_msg=NULL;
asprintf(&send_msg, "get_subbuffer %s", buf->name);
result = ustcomm_send_request(&buf->conn, send_msg, &received_msg);
- if(test_sigpipe()) {
- WARN("process %d destroyed before we could connect to it", buf->pid);
- retval = GET_SUBBUF_DONE;
+ if((result == -1 && errno == EPIPE) || result == 0) {
+ DBG("app died while being traced");
+ retval = GET_SUBBUF_DIED;
goto end;
}
else if(result < 0) {
retval = GET_SUBBUF_DONE;
goto end_rep;
}
+ else if(!strcmp(received_msg, "NOTFOUND")) {
+ WARN("For buffer %s, the trace was not found. This likely means it was destroyed by the user.", buf->name);
+ retval = GET_SUBBUF_DONE;
+ goto end_rep;
+ }
else {
DBG("error getting subbuffer %s", buf->name);
retval = -1;
retval = PUT_SUBBUF_DIED;
goto end;
}
- if(result < 0) {
+ else if(result < 0) {
ERR("put_subbuffer: send_message failed");
retval = -1;
goto end;
}
+ else if(result == 0) {
+ /* Program seems finished. However this might not be
+ * the last subbuffer that has to be collected.
+ */
+ retval = PUT_SUBBUF_DIED;
+ goto end;
+ }
result = sscanf(received_msg, "%as", &rep_code);
if(result != 1) {
DBG("subbuffer put %s", buf->name);
retval = PUT_SUBBUF_OK;
}
+ else if(!strcmp(received_msg, "NOTFOUND")) {
+ WARN("For buffer %s, the trace was not found. This likely means it was destroyed by the user.", buf->name);
+ /* However, maybe this was not the last subbuffer. So
+ * we return the program died.
+ */
+ retval = PUT_SUBBUF_DIED;
+ goto end_rep;
+ }
else {
DBG("put_subbuffer: received error, we were pushed");
retval = PUT_SUBBUF_PUSHED;
return retval;
}
-/* This write is patient because it restarts if it was incomplete.
- */
-
-ssize_t patient_write(int fd, const void *buf, size_t count)
-{
- const char *bufc = (const char *) buf;
- int result;
-
- for(;;) {
- result = write(fd, bufc, count);
- if(result <= 0) {
- return result;
- }
- count -= result;
- bufc += result;
-
- if(count == 0) {
- break;
- }
- }
-
- return bufc-(const char *)buf;
-}
-
void decrement_active_buffers(void *arg)
{
pthread_mutex_lock(&active_buffers_mutex);
pthread_mutex_unlock(&active_buffers_mutex);
}
-void *consumer_thread(void *arg)
-{
- struct buffer_info *buf = (struct buffer_info *) arg;
- int result;
-
- pthread_cleanup_push(decrement_active_buffers, NULL);
-
- for(;;) {
- /* get the subbuffer */
- result = get_subbuffer(buf);
- if(result == -1) {
- ERR("error getting subbuffer");
- continue;
- }
- else if(result == GET_SUBBUF_DONE) {
- /* this is done */
- break;
- }
- else if(result == GET_SUBBUF_DIED) {
- finish_consuming_dead_subbuffer(buf);
- break;
- }
-
- /* write data to file */
- result = patient_write(buf->file_fd, buf->mem + (buf->consumed_old & (buf->n_subbufs * buf->subbuf_size-1)), buf->subbuf_size);
- if(result == -1) {
- PERROR("write");
- /* FIXME: maybe drop this trace */
- }
-
- /* put the subbuffer */
- result = put_subbuffer(buf);
- if(result == -1) {
- ERR("unknown error putting subbuffer (channel=%s)", buf->name);
- break;
- }
- else if(result == PUT_SUBBUF_PUSHED) {
- ERR("Buffer overflow (channel=%s), reader pushed. This channel will not be usable passed this point.", buf->name);
- break;
- }
- else if(result == PUT_SUBBUF_DIED) {
- WARN("application died while putting subbuffer");
- /* FIXME: probably need to skip the first subbuffer in finish_consuming_dead_subbuffer */
- finish_consuming_dead_subbuffer(buf);
- break;
- }
- else if(result == PUT_SUBBUF_OK) {
- }
- }
-
- DBG("thread for buffer %s is stopping", buf->name);
-
- /* FIXME: destroy, unalloc... */
-
- pthread_cleanup_pop(1);
-
- return NULL;
-}
-
int create_dir_if_needed(char *dir)
{
int result;
return 1;
}
-int add_buffer(pid_t pid, char *bufname)
+struct buffer_info *connect_buffer(pid_t pid, const char *bufname)
{
struct buffer_info *buf;
char *send_msg;
int result;
char *tmp;
int fd;
- pthread_t thr;
struct shmid_ds shmds;
buf = (struct buffer_info *) malloc(sizeof(struct buffer_info));
if(buf == NULL) {
ERR("add_buffer: insufficient memory");
- return -1;
+ return NULL;
}
buf->name = bufname;
result = ustcomm_connect_app(buf->pid, &buf->conn);
if(result) {
WARN("unable to connect to process, it probably died before we were able to connect");
- return -1;
+ return NULL;
}
/* get pidunique */
free(send_msg);
if(result == -1) {
ERR("problem in ustcomm_send_request(get_pidunique)");
- return -1;
+ return NULL;
+ }
+ if(result == 0) {
+ goto error;
}
result = sscanf(received_msg, "%lld", &buf->pidunique);
if(result != 1) {
ERR("unable to parse response to get_pidunique");
- return -1;
+ return NULL;
}
free(received_msg);
DBG("got pidunique %lld", buf->pidunique);
free(send_msg);
if(result == -1) {
ERR("problem in ustcomm_send_request(get_shmid)");
- return -1;
+ return NULL;
+ }
+ if(result == 0) {
+ goto error;
}
result = sscanf(received_msg, "%d %d", &buf->shmid, &buf->bufstruct_shmid);
if(result != 2) {
- ERR("unable to parse response to get_shmid");
- return -1;
+ ERR("unable to parse response to get_shmid (\"%s\")", received_msg);
+ return NULL;
}
free(received_msg);
DBG("got shmids %d %d", buf->shmid, buf->bufstruct_shmid);
free(send_msg);
if(result == -1) {
ERR("problem in ustcomm_send_request(g_n_subbufs)");
- return -1;
+ return NULL;
+ }
+ if(result == 0) {
+ goto error;
}
result = sscanf(received_msg, "%d", &buf->n_subbufs);
if(result != 1) {
ERR("unable to parse response to get_n_subbufs");
- return -1;
+ return NULL;
}
free(received_msg);
DBG("got n_subbufs %d", buf->n_subbufs);
/* get subbuf size */
asprintf(&send_msg, "get_subbuf_size %s", buf->name);
- ustcomm_send_request(&buf->conn, send_msg, &received_msg);
+ result = ustcomm_send_request(&buf->conn, send_msg, &received_msg);
free(send_msg);
+ if(result == -1) {
+ ERR("problem in ustcomm_send_request(get_subbuf_size)");
+ return NULL;
+ }
+ if(result == 0) {
+ goto error;
+ }
result = sscanf(received_msg, "%d", &buf->subbuf_size);
if(result != 1) {
ERR("unable to parse response to get_subbuf_size");
- return -1;
+ return NULL;
}
free(received_msg);
DBG("got subbuf_size %d", buf->subbuf_size);
buf->mem = shmat(buf->shmid, NULL, 0);
if(buf->mem == (void *) 0) {
PERROR("shmat");
- return -1;
+ return NULL;
}
DBG("successfully attached buffer memory");
buf->bufstruct_mem = shmat(buf->bufstruct_shmid, NULL, 0);
if(buf->bufstruct_mem == (void *) 0) {
PERROR("shmat");
- return -1;
+ return NULL;
}
DBG("successfully attached buffer bufstruct memory");
result = shmctl(buf->shmid, IPC_STAT, &shmds);
if(result == -1) {
PERROR("shmctl");
- return -1;
+ return NULL;
}
buf->memlen = shmds.shm_segsz;
result = create_dir_if_needed(USTD_DEFAULT_TRACE_PATH);
if(result == -1) {
ERR("could not create directory %s", USTD_DEFAULT_TRACE_PATH);
- return -1;
+ return NULL;
}
trace_path = USTD_DEFAULT_TRACE_PATH;
if(result == -1) {
ERR("could not create directory %s", tmp);
free(tmp);
- return -1;
+ return NULL;
}
free(tmp);
- asprintf(&tmp, "%s/%u_%lld/%s_0", trace_path, buf->pid, buf->pidunique, buf->name);
+ asprintf(&tmp, "%s/%u_%lld/%s", trace_path, buf->pid, buf->pidunique, buf->name);
result = fd = open(tmp, O_WRONLY | O_CREAT | O_TRUNC | O_EXCL, 00600);
if(result == -1) {
PERROR("open");
ERR("failed opening trace file %s", tmp);
- return -1;
+ return NULL;
}
buf->file_fd = fd;
free(tmp);
active_buffers++;
pthread_mutex_unlock(&active_buffers_mutex);
- pthread_create(&thr, NULL, consumer_thread, buf);
+ return buf;
+
+error:
+ free(buf);
+ return NULL;
+}
+
+int unwrite_last_subbuffer(struct buffer_info *buf)
+{
+ int result;
+
+ result = ftruncate(buf->file_fd, buf->previous_offset);
+ if(result == -1) {
+ PERROR("ftruncate");
+ return -1;
+ }
+
+ result = lseek(buf->file_fd, buf->previous_offset, SEEK_SET);
+ if(result == (int)(off_t)-1) {
+ PERROR("lseek");
+ return -1;
+ }
+
+ return 0;
+}
+
+int write_current_subbuffer(struct buffer_info *buf)
+{
+ int result;
+
+ void *subbuf_mem = buf->mem + (buf->consumed_old & (buf->n_subbufs * buf->subbuf_size-1));
+
+ size_t cur_sb_size = subbuffer_data_size(subbuf_mem);
+
+ off_t cur_offset = lseek(buf->file_fd, 0, SEEK_CUR);
+ if(cur_offset == (off_t)-1) {
+ PERROR("lseek");
+ return -1;
+ }
+
+ buf->previous_offset = cur_offset;
+ DBG("previous_offset: %ld", cur_offset);
+
+ result = patient_write(buf->file_fd, subbuf_mem, cur_sb_size);
+ if(result == -1) {
+ PERROR("write");
+ /* FIXME: maybe drop this trace */
+ return -1;
+ }
+
+ return 0;
+}
+
+int consumer_loop(struct buffer_info *buf)
+{
+ int result;
+
+ pthread_cleanup_push(decrement_active_buffers, NULL);
+
+ for(;;) {
+ /* get the subbuffer */
+ result = get_subbuffer(buf);
+ if(result == -1) {
+ ERR("error getting subbuffer");
+ continue;
+ }
+ else if(result == GET_SUBBUF_DONE) {
+ /* this is done */
+ break;
+ }
+ else if(result == GET_SUBBUF_DIED) {
+ finish_consuming_dead_subbuffer(buf);
+ break;
+ }
+
+ /* write data to file */
+ write_current_subbuffer(buf);
+ /* FIXME: handle return value? */
+
+ /* put the subbuffer */
+ result = put_subbuffer(buf);
+ if(result == -1) {
+ ERR("unknown error putting subbuffer (channel=%s)", buf->name);
+ break;
+ }
+ else if(result == PUT_SUBBUF_PUSHED) {
+ ERR("Buffer overflow (channel=%s), reader pushed. This channel will not be usable passed this point.", buf->name);
+ break;
+ }
+ else if(result == PUT_SUBBUF_DIED) {
+ WARN("application died while putting subbuffer");
+ /* Skip the first subbuffer. We are not sure it is trustable
+ * because the put_subbuffer() did not complete.
+ */
+ unwrite_last_subbuffer(buf);
+ finish_consuming_dead_subbuffer(buf);
+ break;
+ }
+ else if(result == PUT_SUBBUF_DONE) {
+ /* Done with this subbuffer */
+ /* FIXME: add a case where this branch is used? Upon
+ * normal trace termination, at put_subbuf time, a
+ * special last-subbuffer code could be returned by
+ * the listener.
+ */
+ break;
+ }
+ else if(result == PUT_SUBBUF_OK) {
+ }
+ }
+
+ DBG("thread for buffer %s is stopping", buf->name);
+
+ /* FIXME: destroy, unalloc... */
+
+ pthread_cleanup_pop(1);
+
+ return 0;
+}
+
+void free_buffer(struct buffer_info *buf)
+{
+}
+
+struct consumer_thread_args {
+ pid_t pid;
+ const char *bufname;
+};
+
+void *consumer_thread(void *arg)
+{
+ struct buffer_info *buf = (struct buffer_info *) arg;
+ struct consumer_thread_args *args = (struct consumer_thread_args *) arg;
+
+ DBG("GOT ARGS: pid %d bufname %s", args->pid, args->bufname);
+
+ buf = connect_buffer(args->pid, args->bufname);
+ if(buf == NULL) {
+ ERR("failed to connect to buffer");
+ goto end;
+ }
+
+ consumer_loop(buf);
+
+ free_buffer(buf);
+
+ end:
+ /* bufname is free'd in free_buffer() */
+ free(args);
+ return NULL;
+}
+
+int start_consuming_buffer(pid_t pid, const char *bufname)
+{
+ pthread_t thr;
+ struct consumer_thread_args *args;
+
+ DBG("beginning of start_consuming_buffer: args: pid %d bufname %s", pid, bufname);
+
+ args = (struct consumer_thread_args *) malloc(sizeof(struct consumer_thread_args));
+
+ args->pid = pid;
+ args->bufname = strdup(bufname);
+ DBG("beginning2 of start_consuming_buffer: args: pid %d bufname %s", args->pid, args->bufname);
+
+ pthread_create(&thr, NULL, consumer_thread, args);
+ DBG("end of start_consuming_buffer: args: pid %d bufname %s", args->pid, args->bufname);
return 0;
}
fprintf(stderr, "Usage:\nustd OPTIONS\n\nOptions:\n"
"\t-h\t\tDisplay this usage.\n"
"\t-o DIR\t\tSpecify the directory where to output the traces.\n"
- "\t-s PATH\t\tSpecify the path to use for the daemon socket.\n");
+ "\t-s PATH\t\tSpecify the path to use for the daemon socket.\n"
+ "\t-d\t\tStart as a daemon.\n"
+ "\t--pidfile FILE\tWrite the PID in this file (when using -d).\n");
}
int parse_args(int argc, char **argv)
while (1) {
int option_index = 0;
static struct option long_options[] = {
+ {"pidfile", 1, 0, 'p'},
{"help", 0, 0, 'h'},
{"version", 0, 0, 'V'},
{0, 0, 0, 0}
};
- c = getopt_long(argc, argv, "hs:o:", long_options, &option_index);
+ c = getopt_long(argc, argv, "hs:o:d", long_options, &option_index);
if (c == -1)
break;
return -1;
}
break;
+ case 'd':
+ daemon_mode = 1;
+ break;
+ case 'p':
+ pidfile = strdup(optarg);
+ break;
case 'h':
usage();
exit(0);
terminate_req = 1;
}
-int main(int argc, char **argv)
+static int write_pidfile(const char *file_name, pid_t pid)
+{
+ FILE *pidfp;
+
+ pidfp = fopen(file_name, "w");
+ if(!pidfp) {
+ PERROR("fopen (%s)", pidfile);
+ WARN("killing child process");
+ return -1;
+ }
+
+ fprintf(pidfp, "%d\n", pid);
+
+ fclose(pidfp);
+
+ return 0;
+}
+
+int start_ustd(int fd)
{
struct ustcomm_ustd ustd;
int result;
PERROR("sigaction");
return 1;
}
-
- result = parse_args(argc, argv);
+ result = sigaction(SIGINT, &sa, NULL);
if(result == -1) {
- exit(1);
+ PERROR("sigaction");
+ return 1;
}
result = ustcomm_init_ustd(&ustd, sock_path);
return 1;
}
+ /* Write pidfile */
+ if(pidfile) {
+ result = write_pidfile(pidfile, getpid());
+ if(result == -1) {
+ ERR("failed to write pidfile");
+ return 1;
+ }
+ }
+
+ /* Notify parent that we are successfully started. */
+ if(fd != -1) {
+ /* write any one character */
+ result = write(fd, "!", 1);
+ if(result == -1) {
+ PERROR("write");
+ return -1;
+ }
+ if(result != 1) {
+ ERR("Problem sending confirmation of daemon start to parent");
+ return -1;
+ }
+ result = close(fd);
+ if(result == -1) {
+ PERROR("close");
+ }
+ }
+
/* app loop */
for(;;) {
char *recvbuf;
result = ustcomm_ustd_recv_message(&ustd, &recvbuf, NULL, 100);
if(result == -1) {
ERR("error in ustcomm_ustd_recv_message");
- continue;
+ goto loop_end;
}
if(result > 0) {
if(!strncmp(recvbuf, "collect", 7)) {
result = sscanf(recvbuf, "%*s %d %50as", &pid, &bufname);
if(result != 2) {
- fprintf(stderr, "parsing error: %s\n", recvbuf);
+ ERR("parsing error: %s", recvbuf);
+ goto free_bufname;
}
- result = add_buffer(pid, bufname);
+ result = start_consuming_buffer(pid, bufname);
if(result < 0) {
ERR("error in add_buffer");
- continue;
+ goto free_bufname;
}
+
+ free_bufname:
+ free(bufname);
+ }
+ else {
+ WARN("unknown command: %s", recvbuf);
}
free(recvbuf);
}
+ loop_end:
+
if(terminate_req) {
pthread_mutex_lock(&active_buffers_mutex);
if(active_buffers == 0) {
}
}
+ ustcomm_fini_ustd(&ustd);
+
return 0;
}
+
+int start_ustd_daemon()
+{
+ int result;
+ int fd[2];
+ pid_t child_pid;
+
+ result = pipe(fd);
+
+ result = child_pid = fork();
+ if(result == -1) {
+ PERROR("fork");
+ return -1;
+ }
+ else if(result == 0) {
+ return start_ustd(fd[1]);
+ }
+ else {
+ char buf;
+
+ result = read(fd[0], &buf, 1);
+ if(result == -1) {
+ PERROR("read");
+ return -1;
+ }
+ if(result != 1) {
+ ERR("did not receive valid confirmation that the daemon is started");
+ return -1;
+ }
+
+ result = close(fd[0]);
+ if(result == -1) {
+ PERROR("close");
+ }
+
+ DBG("The daemon is now successfully started");
+ }
+
+ /* Wait for confirmation that the server is ready. */
+
+
+ return 0;
+}
+
+int main(int argc, char **argv)
+{
+ int result;
+
+ result = parse_args(argc, argv);
+ if(result == -1) {
+ exit(1);
+ }
+
+ if(daemon_mode) {
+ result = start_ustd_daemon();
+ }
+ else {
+ result = start_ustd(-1);
+ }
+
+ return result;
+}