[lttng-ust.git] / ustd / ustd.c

/* Copyright (C) 2009  Pierre-Marc Fournier
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301 USA
 */

#define _GNU_SOURCE

#include <sys/types.h>
#include <sys/stat.h>
#include <sys/shm.h>
#include <fcntl.h>
#include <unistd.h>
#include <pthread.h>
#include <signal.h>

#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <errno.h>
#include <assert.h>
#include <getopt.h>

#include "ustd.h"
#include "localerr.h"
#include "ustcomm.h"
#include "share.h"

/* return value: 0 = subbuffer is finished, it won't produce data anymore
 *               1 = got subbuffer successfully
 *               <0 = error
 */

#define GET_SUBBUF_OK 1
#define GET_SUBBUF_DONE 0
#define GET_SUBBUF_DIED 2

#define PUT_SUBBUF_OK 1
#define PUT_SUBBUF_DIED 0
#define PUT_SUBBUF_PUSHED 2

char *sock_path=NULL;
char *trace_path=NULL;

/* Number of active buffers and the mutex to protect it. */
int active_buffers = 0;
pthread_mutex_t active_buffers_mutex = PTHREAD_MUTEX_INITIALIZER;
/* Whether a request to end the program was received. */
sig_atomic_t terminate_req = 0;

int get_subbuffer(struct buffer_info *buf)
{
	char *send_msg=NULL;
	char *received_msg=NULL;
	char *rep_code=NULL;
	int retval;
	int result;

	asprintf(&send_msg, "get_subbuffer %s", buf->name);
	result = ustcomm_send_request(&buf->conn, send_msg, &received_msg);
	if((result == -1 && errno == EPIPE) || result == 0) {
		DBG("app died while being traced");
		retval = GET_SUBBUF_DIED;
		goto end;
	}
	else if(result < 0) {
		ERR("get_subbuffer: ustcomm_send_request failed");
		retval = -1;
		goto end;
	}

	result = sscanf(received_msg, "%as %ld", &rep_code, &buf->consumed_old);
	if(result != 2 && result != 1) {
		ERR("unable to parse response to get_subbuffer");
		retval = -1;
		goto end_rep;
	}

	DBG("received msg is %s", received_msg);

	if(!strcmp(rep_code, "OK")) {
		DBG("got subbuffer %s", buf->name);
		retval = GET_SUBBUF_OK;
	}
	else if(nth_token_is(received_msg, "END", 0) == 1) {
		retval = GET_SUBBUF_DONE;
		goto end_rep;
	}
	else {
		DBG("error getting subbuffer %s", buf->name);
		retval = -1;
	}

	/* FIMXE: free correctly the stuff */
end_rep:
	if(rep_code)
		free(rep_code);
end:
	if(send_msg)
		free(send_msg);
	if(received_msg)
		free(received_msg);

	return retval;
}

int put_subbuffer(struct buffer_info *buf)
{
	char *send_msg=NULL;
	char *received_msg=NULL;
	char *rep_code=NULL;
	int retval;
	int result;

	asprintf(&send_msg, "put_subbuffer %s %ld", buf->name, buf->consumed_old);
	result = ustcomm_send_request(&buf->conn, send_msg, &received_msg);
	if(result < 0 && errno == ECONNRESET) {
		retval = PUT_SUBBUF_DIED;
		goto end;
	}
	if(result < 0) {
		ERR("put_subbuffer: send_message failed");
		retval = -1;
		goto end;
	}

	result = sscanf(received_msg, "%as", &rep_code);
	if(result != 1) {
		ERR("unable to parse response to put_subbuffer");
		retval = -1;
		goto end_rep;
	}

	if(!strcmp(rep_code, "OK")) {
		DBG("subbuffer put %s", buf->name);
		retval = PUT_SUBBUF_OK;
	}
	else {
		DBG("put_subbuffer: received error, we were pushed");
		retval = PUT_SUBBUF_PUSHED;
		goto end_rep;
	}

end_rep:
	if(rep_code)
		free(rep_code);

end:
	if(send_msg)
		free(send_msg);
	if(received_msg)
		free(received_msg);

	return retval;
}

void decrement_active_buffers(void *arg)
{
	pthread_mutex_lock(&active_buffers_mutex);
	active_buffers--;
	pthread_mutex_unlock(&active_buffers_mutex);
}

int create_dir_if_needed(char *dir)
{
	int result;
	result = mkdir(dir, 0777);
	if(result == -1) {
		if(errno != EEXIST) {
			PERROR("mkdir");
			return -1;
		}
	}

	return 0;
}

int is_directory(const char *dir)
{
	int result;
	struct stat st;

	result = stat(dir, &st);
	if(result == -1) {
		PERROR("stat");
		return 0;
	}

	if(!S_ISDIR(st.st_mode)) {
		return 0;
	}

	return 1;
}

struct buffer_info *connect_buffer(pid_t pid, const char *bufname)
{
	struct buffer_info *buf;
	char *send_msg;
	char *received_msg;
	int result;
	char *tmp;
	int fd;
	struct shmid_ds shmds;

	buf = (struct buffer_info *) malloc(sizeof(struct buffer_info));
	if(buf == NULL) {
		ERR("add_buffer: insufficient memory");
		return NULL;
	}

	buf->name = bufname;
	buf->pid = pid;

	/* connect to app */
	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 NULL;
	}

	/* get pidunique */
	asprintf(&send_msg, "get_pidunique");
	result = ustcomm_send_request(&buf->conn, send_msg, &received_msg);
	free(send_msg);
	if(result == -1) {
		ERR("problem in ustcomm_send_request(get_pidunique)");
		return NULL;
	}

	result = sscanf(received_msg, "%lld", &buf->pidunique);
	if(result != 1) {
		ERR("unable to parse response to get_pidunique");
		return NULL;
	}
	free(received_msg);
	DBG("got pidunique %lld", buf->pidunique);

	/* get shmid */
	asprintf(&send_msg, "get_shmid %s", buf->name);
	result = ustcomm_send_request(&buf->conn, send_msg, &received_msg);
	free(send_msg);
	if(result == -1) {
		ERR("problem in ustcomm_send_request(get_shmid)");
		return NULL;
	}

	result = sscanf(received_msg, "%d %d", &buf->shmid, &buf->bufstruct_shmid);
	if(result != 2) {
		ERR("unable to parse response to get_shmid");
		return NULL;
	}
	free(received_msg);
	DBG("got shmids %d %d", buf->shmid, buf->bufstruct_shmid);

	/* get n_subbufs */
	asprintf(&send_msg, "get_n_subbufs %s", buf->name);
	result = ustcomm_send_request(&buf->conn, send_msg, &received_msg);
	free(send_msg);
	if(result == -1) {
		ERR("problem in ustcomm_send_request(g_n_subbufs)");
		return NULL;
	}

	result = sscanf(received_msg, "%d", &buf->n_subbufs);
	if(result != 1) {
		ERR("unable to parse response to get_n_subbufs");
		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);
	free(send_msg);

	result = sscanf(received_msg, "%d", &buf->subbuf_size);
	if(result != 1) {
		ERR("unable to parse response to get_subbuf_size");
		return NULL;
	}
	free(received_msg);
	DBG("got subbuf_size %d", buf->subbuf_size);

	/* attach memory */
	buf->mem = shmat(buf->shmid, NULL, 0);
	if(buf->mem == (void *) 0) {
		PERROR("shmat");
		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 NULL;
	}
	DBG("successfully attached buffer bufstruct memory");

	/* obtain info on the memory segment */
	result = shmctl(buf->shmid, IPC_STAT, &shmds);
	if(result == -1) {
		PERROR("shmctl");
		return NULL;
	}
	buf->memlen = shmds.shm_segsz;

	/* open file for output */
	if(!trace_path) {
		/* Only create the directory if using the default path, because
		 * of the risk of typo when using trace path override. We don't
		 * want to risk creating plenty of useless directories in that case.
		 */
		result = create_dir_if_needed(USTD_DEFAULT_TRACE_PATH);
		if(result == -1) {
			ERR("could not create directory %s", USTD_DEFAULT_TRACE_PATH);
			return NULL;
		}

		trace_path = USTD_DEFAULT_TRACE_PATH;
	}

	asprintf(&tmp, "%s/%u_%lld", trace_path, buf->pid, buf->pidunique);
	result = create_dir_if_needed(tmp);
	if(result == -1) {
		ERR("could not create directory %s", tmp);
		free(tmp);
		return NULL;
	}
	free(tmp);

	asprintf(&tmp, "%s/%u_%lld/%s_0", 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 NULL;
	}
	buf->file_fd = fd;
	free(tmp);

	pthread_mutex_lock(&active_buffers_mutex);
	active_buffers++;
	pthread_mutex_unlock(&active_buffers_mutex);

	return buf;
}

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 */
		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 */
		/* FIXME: we actually should unput the buffer before consuming... */
		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 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;
}

void usage(void)
{
	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");
}

int parse_args(int argc, char **argv)
{
	int c;

	while (1) {
		int option_index = 0;
		static struct option long_options[] = {
			{"help", 0, 0, 'h'},
			{"version", 0, 0, 'V'},
			{0, 0, 0, 0}
		};

		c = getopt_long(argc, argv, "hs:o:", long_options, &option_index);
		if (c == -1)
			break;

		switch (c) {
		case 0:
			printf("option %s", long_options[option_index].name);
			if (optarg)
				printf(" with arg %s", optarg);
			printf("\n");
			break;
		case 's':
			sock_path = optarg;
			break;
		case 'o':
			trace_path = optarg;
			if(!is_directory(trace_path)) {
				ERR("Not a valid directory. (%s)", trace_path);
				return -1;
			}
			break;
		case 'h':
			usage();
			exit(0);
		case 'V':
			printf("Version 0.0\n");
			break;

		default:
			/* unknown option or other error; error is
			printed by getopt, just return */
			return -1;
		}
	}

	return 0;
}

void sigterm_handler(int sig)
{
	terminate_req = 1;
}

int main(int argc, char **argv)
{
	struct ustcomm_ustd ustd;
	int result;
	sigset_t sigset;
	struct sigaction sa;

	result = sigemptyset(&sigset);
	if(result == -1) {
		PERROR("sigemptyset");
		return 1;
	}
	sa.sa_handler = sigterm_handler;
	sa.sa_mask = sigset;
	sa.sa_flags = SA_RESTART;
	result = sigaction(SIGTERM, &sa, NULL);
	if(result == -1) {
		PERROR("sigaction");
		return 1;
	}

	result = parse_args(argc, argv);
	if(result == -1) {
		exit(1);
	}

	result = ustcomm_init_ustd(&ustd, sock_path);
	if(result == -1) {
		ERR("failed to initialize socket");
		return 1;
	}

	/* setup handler for SIGPIPE */
	result = sigemptyset(&sigset);
	if(result == -1) {
		PERROR("sigemptyset");
		return 1;
	}
	result = sigaddset(&sigset, SIGPIPE);
	if(result == -1) {
		PERROR("sigaddset");
		return 1;
	}
	result = sigprocmask(SIG_BLOCK, &sigset, NULL);
	if(result == -1) {
		PERROR("sigprocmask");
		return 1;
	}

	/* app loop */
	for(;;) {
		char *recvbuf;

		/* check for requests on our public socket */
		result = ustcomm_ustd_recv_message(&ustd, &recvbuf, NULL, 100);
		if(result == -1) {
			ERR("error in ustcomm_ustd_recv_message");
			goto loop_end;
		}
		if(result > 0) {
			if(!strncmp(recvbuf, "collect", 7)) {
				pid_t pid;
				char *bufname;
				int result;

				result = sscanf(recvbuf, "%*s %d %50as", &pid, &bufname);
				if(result != 2) {
					ERR("parsing error: %s", recvbuf);
					goto free_bufname;
				}

				result = start_consuming_buffer(pid, bufname);
				if(result < 0) {
					ERR("error in add_buffer");
					goto free_bufname;
				}

				free_bufname:
				free(bufname);
			}

			free(recvbuf);
		}

		loop_end:

		if(terminate_req) {
			pthread_mutex_lock(&active_buffers_mutex);
			if(active_buffers == 0) {
				pthread_mutex_unlock(&active_buffers_mutex);
				break;
			}
			pthread_mutex_unlock(&active_buffers_mutex);
		}
	}

	return 0;
}
Commit	Line	Data
c39c72ee	1	/* Copyright (C) 2009 Pierre-Marc Fournier
1f8b0dff	2	*
c39c72ee PMF	3	* This library is free software; you can redistribute it and/or
	4	* modify it under the terms of the GNU Lesser General Public
	5	* License as published by the Free Software Foundation; either
	6	* version 2.1 of the License, or (at your option) any later version.
1f8b0dff	7	*
c39c72ee	8	* This library is distributed in the hope that it will be useful,
1f8b0dff	9	* but WITHOUT ANY WARRANTY; without even the implied warranty of
c39c72ee PMF	10	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
c39c72ee PMF	11	* Lesser General Public License for more details.
1f8b0dff	12	*
c39c72ee PMF	13	* You should have received a copy of the GNU Lesser General Public
	14	* License along with this library; if not, write to the Free Software
	15	* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
1f8b0dff PMF	16	*/
1f8b0dff PMF	17
3796af9b PMF	18	#define _GNU_SOURCE
	19
	20	#include <sys/types.h>
cd226f25	21	#include <sys/stat.h>
3796af9b	22	#include <sys/shm.h>
688760ef PMF	23	#include <fcntl.h>
688760ef PMF	24	#include <unistd.h>
3a7b90de	25	#include <pthread.h>
a3cdd4a7	26	#include <signal.h>
3796af9b PMF	27
	28	#include <stdlib.h>
	29	#include <stdio.h>
	30	#include <string.h>
a3cdd4a7 PMF	31	#include <errno.h>
a3cdd4a7 PMF	32	#include <assert.h>
cd226f25	33	#include <getopt.h>
3796af9b	34
0b0cd937	35	#include "ustd.h"
3796af9b PMF	36	#include "localerr.h"
3796af9b PMF	37	#include "ustcomm.h"
8bf5ab2d	38	#include "share.h"
3796af9b	39
3a7b90de PMF	40	/* return value: 0 = subbuffer is finished, it won't produce data anymore
	41	* 1 = got subbuffer successfully
	42	* <0 = error
	43	*/
3796af9b	44
8cefc145 PMF	45	#define GET_SUBBUF_OK 1
	46	#define GET_SUBBUF_DONE 0
	47	#define GET_SUBBUF_DIED 2
	48
a3cdd4a7 PMF	49	#define PUT_SUBBUF_OK 1
	50	#define PUT_SUBBUF_DIED 0
	51	#define PUT_SUBBUF_PUSHED 2
	52
c97d4437	53	char *sock_path=NULL;
cd226f25 PMF	54	char *trace_path=NULL;
cd226f25 PMF	55
3158b808 PMF	56	/* Number of active buffers and the mutex to protect it. */
	57	int active_buffers = 0;
	58	pthread_mutex_t active_buffers_mutex = PTHREAD_MUTEX_INITIALIZER;
	59	/* Whether a request to end the program was received. */
	60	sig_atomic_t terminate_req = 0;
	61
688760ef PMF	62	int get_subbuffer(struct buffer_info *buf)
688760ef PMF	63	{
ab805ccd PMF	64	char *send_msg=NULL;
	65	char *received_msg=NULL;
	66	char *rep_code=NULL;
688760ef PMF	67	int retval;
	68	int result;
	69
	70	asprintf(&send_msg, "get_subbuffer %s", buf->name);
3bb56863	71	result = ustcomm_send_request(&buf->conn, send_msg, &received_msg);
dc2f5ffa	72	if((result == -1 && errno == EPIPE) \|\| result == 0) {
409e2abe PMF	73	DBG("app died while being traced");
409e2abe PMF	74	retval = GET_SUBBUF_DIED;
ab805ccd	75	goto end;
a3cdd4a7 PMF	76	}
a3cdd4a7 PMF	77	else if(result < 0) {
3bb56863	78	ERR("get_subbuffer: ustcomm_send_request failed");
ab805ccd PMF	79	retval = -1;
ab805ccd PMF	80	goto end;
688760ef	81	}
688760ef PMF	82
688760ef PMF	83	result = sscanf(received_msg, "%as %ld", &rep_code, &buf->consumed_old);
3a7b90de	84	if(result != 2 && result != 1) {
688760ef	85	ERR("unable to parse response to get_subbuffer");
ab805ccd PMF	86	retval = -1;
ab805ccd PMF	87	goto end_rep;
688760ef	88	}
3a7b90de PMF	89
3a7b90de PMF	90	DBG("received msg is %s", received_msg);
688760ef PMF	91
	92	if(!strcmp(rep_code, "OK")) {
	93	DBG("got subbuffer %s", buf->name);
8cefc145	94	retval = GET_SUBBUF_OK;
688760ef	95	}
3a7b90de	96	else if(nth_token_is(received_msg, "END", 0) == 1) {
ab805ccd PMF	97	retval = GET_SUBBUF_DONE;
ab805ccd PMF	98	goto end_rep;
3a7b90de	99	}
688760ef	100	else {
3a7b90de PMF	101	DBG("error getting subbuffer %s", buf->name);
3a7b90de PMF	102	retval = -1;
688760ef PMF	103	}
688760ef PMF	104
3a7b90de	105	/* FIMXE: free correctly the stuff */
ab805ccd PMF	106	end_rep:
	107	if(rep_code)
	108	free(rep_code);
	109	end:
	110	if(send_msg)
	111	free(send_msg);
	112	if(received_msg)
	113	free(received_msg);
	114
688760ef PMF	115	return retval;
	116	}
	117
	118	int put_subbuffer(struct buffer_info *buf)
	119	{
ab805ccd PMF	120	char *send_msg=NULL;
	121	char *received_msg=NULL;
	122	char *rep_code=NULL;
688760ef PMF	123	int retval;
	124	int result;
	125
	126	asprintf(&send_msg, "put_subbuffer %s %ld", buf->name, buf->consumed_old);
3bb56863	127	result = ustcomm_send_request(&buf->conn, send_msg, &received_msg);
ab805ccd PMF	128	if(result < 0 && errno == ECONNRESET) {
	129	retval = PUT_SUBBUF_DIED;
	130	goto end;
	131	}
688760ef PMF	132	if(result < 0) {
688760ef PMF	133	ERR("put_subbuffer: send_message failed");
ab805ccd PMF	134	retval = -1;
ab805ccd PMF	135	goto end;
688760ef	136	}
688760ef PMF	137
	138	result = sscanf(received_msg, "%as", &rep_code);
	139	if(result != 1) {
	140	ERR("unable to parse response to put_subbuffer");
ab805ccd PMF	141	retval = -1;
ab805ccd PMF	142	goto end_rep;
688760ef	143	}
688760ef PMF	144
	145	if(!strcmp(rep_code, "OK")) {
	146	DBG("subbuffer put %s", buf->name);
a3cdd4a7	147	retval = PUT_SUBBUF_OK;
688760ef PMF	148	}
688760ef PMF	149	else {
a3cdd4a7	150	DBG("put_subbuffer: received error, we were pushed");
ab805ccd PMF	151	retval = PUT_SUBBUF_PUSHED;
ab805ccd PMF	152	goto end_rep;
688760ef PMF	153	}
688760ef PMF	154
ab805ccd PMF	155	end_rep:
	156	if(rep_code)
	157	free(rep_code);
	158
	159	end:
	160	if(send_msg)
	161	free(send_msg);
	162	if(received_msg)
	163	free(received_msg);
	164
688760ef PMF	165	return retval;
	166	}
	167
3158b808 PMF	168	void decrement_active_buffers(void *arg)
	169	{
	170	pthread_mutex_lock(&active_buffers_mutex);
	171	active_buffers--;
	172	pthread_mutex_unlock(&active_buffers_mutex);
	173	}
	174
72ebd39a PMF	175	int create_dir_if_needed(char *dir)
	176	{
	177	int result;
	178	result = mkdir(dir, 0777);
	179	if(result == -1) {
	180	if(errno != EEXIST) {
4d70f833	181	PERROR("mkdir");
72ebd39a PMF	182	return -1;
	183	}
	184	}
	185
	186	return 0;
	187	}
	188
cd226f25 PMF	189	int is_directory(const char *dir)
	190	{
	191	int result;
	192	struct stat st;
	193
	194	result = stat(dir, &st);
	195	if(result == -1) {
	196	PERROR("stat");
	197	return 0;
	198	}
	199
	200	if(!S_ISDIR(st.st_mode)) {
	201	return 0;
	202	}
	203
	204	return 1;
	205	}
	206
f99c0b5c	207	struct buffer_info connect_buffer(pid_t pid, const char bufname)
3a7b90de PMF	208	{
	209	struct buffer_info *buf;
	210	char *send_msg;
	211	char *received_msg;
	212	int result;
	213	char *tmp;
	214	int fd;
a3cdd4a7	215	struct shmid_ds shmds;
3a7b90de PMF	216
	217	buf = (struct buffer_info *) malloc(sizeof(struct buffer_info));
	218	if(buf == NULL) {
	219	ERR("add_buffer: insufficient memory");
f99c0b5c	220	return NULL;
3a7b90de PMF	221	}
	222
	223	buf->name = bufname;
	224	buf->pid = pid;
	225
4e2a8808 PMF	226	/* connect to app */
	227	result = ustcomm_connect_app(buf->pid, &buf->conn);
	228	if(result) {
a3cdd4a7	229	WARN("unable to connect to process, it probably died before we were able to connect");
f99c0b5c	230	return NULL;
4e2a8808 PMF	231	}
4e2a8808 PMF	232
ed1317e7 PMF	233	/* get pidunique */
	234	asprintf(&send_msg, "get_pidunique");
	235	result = ustcomm_send_request(&buf->conn, send_msg, &received_msg);
	236	free(send_msg);
	237	if(result == -1) {
	238	ERR("problem in ustcomm_send_request(get_pidunique)");
f99c0b5c	239	return NULL;
ed1317e7 PMF	240	}
	241
	242	result = sscanf(received_msg, "%lld", &buf->pidunique);
	243	if(result != 1) {
	244	ERR("unable to parse response to get_pidunique");
f99c0b5c	245	return NULL;
ed1317e7 PMF	246	}
	247	free(received_msg);
	248	DBG("got pidunique %lld", buf->pidunique);
	249
3a7b90de PMF	250	/* get shmid */
3a7b90de PMF	251	asprintf(&send_msg, "get_shmid %s", buf->name);
a3cdd4a7	252	result = ustcomm_send_request(&buf->conn, send_msg, &received_msg);
3a7b90de	253	free(send_msg);
a3cdd4a7 PMF	254	if(result == -1) {
a3cdd4a7 PMF	255	ERR("problem in ustcomm_send_request(get_shmid)");
f99c0b5c	256	return NULL;
a3cdd4a7	257	}
3a7b90de	258
8cefc145 PMF	259	result = sscanf(received_msg, "%d %d", &buf->shmid, &buf->bufstruct_shmid);
8cefc145 PMF	260	if(result != 2) {
3a7b90de	261	ERR("unable to parse response to get_shmid");
f99c0b5c	262	return NULL;
3a7b90de PMF	263	}
3a7b90de PMF	264	free(received_msg);
8cefc145	265	DBG("got shmids %d %d", buf->shmid, buf->bufstruct_shmid);
3a7b90de PMF	266
	267	/* get n_subbufs */
	268	asprintf(&send_msg, "get_n_subbufs %s", buf->name);
a3cdd4a7	269	result = ustcomm_send_request(&buf->conn, send_msg, &received_msg);
3a7b90de	270	free(send_msg);
a3cdd4a7 PMF	271	if(result == -1) {
a3cdd4a7 PMF	272	ERR("problem in ustcomm_send_request(g_n_subbufs)");
f99c0b5c	273	return NULL;
a3cdd4a7	274	}
3a7b90de PMF	275
	276	result = sscanf(received_msg, "%d", &buf->n_subbufs);
	277	if(result != 1) {
	278	ERR("unable to parse response to get_n_subbufs");
f99c0b5c	279	return NULL;
3a7b90de PMF	280	}
	281	free(received_msg);
	282	DBG("got n_subbufs %d", buf->n_subbufs);
	283
	284	/* get subbuf size */
	285	asprintf(&send_msg, "get_subbuf_size %s", buf->name);
4e2a8808	286	ustcomm_send_request(&buf->conn, send_msg, &received_msg);
3a7b90de PMF	287	free(send_msg);
	288
	289	result = sscanf(received_msg, "%d", &buf->subbuf_size);
	290	if(result != 1) {
	291	ERR("unable to parse response to get_subbuf_size");
f99c0b5c	292	return NULL;
3a7b90de PMF	293	}
	294	free(received_msg);
	295	DBG("got subbuf_size %d", buf->subbuf_size);
	296
	297	/* attach memory */
	298	buf->mem = shmat(buf->shmid, NULL, 0);
	299	if(buf->mem == (void *) 0) {
4d70f833	300	PERROR("shmat");
f99c0b5c	301	return NULL;
3a7b90de	302	}
8cefc145 PMF	303	DBG("successfully attached buffer memory");
	304
	305	buf->bufstruct_mem = shmat(buf->bufstruct_shmid, NULL, 0);
	306	if(buf->bufstruct_mem == (void *) 0) {
4d70f833	307	PERROR("shmat");
f99c0b5c	308	return NULL;
8cefc145 PMF	309	}
8cefc145 PMF	310	DBG("successfully attached buffer bufstruct memory");
3a7b90de	311
a3cdd4a7 PMF	312	/* obtain info on the memory segment */
	313	result = shmctl(buf->shmid, IPC_STAT, &shmds);
	314	if(result == -1) {
4d70f833	315	PERROR("shmctl");
f99c0b5c	316	return NULL;
a3cdd4a7 PMF	317	}
	318	buf->memlen = shmds.shm_segsz;
	319
3a7b90de	320	/* open file for output */
cd226f25 PMF	321	if(!trace_path) {
	322	/* Only create the directory if using the default path, because
	323	* of the risk of typo when using trace path override. We don't
	324	* want to risk creating plenty of useless directories in that case.
	325	*/
	326	result = create_dir_if_needed(USTD_DEFAULT_TRACE_PATH);
	327	if(result == -1) {
	328	ERR("could not create directory %s", USTD_DEFAULT_TRACE_PATH);
f99c0b5c	329	return NULL;
cd226f25 PMF	330	}
	331
	332	trace_path = USTD_DEFAULT_TRACE_PATH;
72ebd39a PMF	333	}
72ebd39a PMF	334
ed1317e7	335	asprintf(&tmp, "%s/%u_%lld", trace_path, buf->pid, buf->pidunique);
72ebd39a PMF	336	result = create_dir_if_needed(tmp);
	337	if(result == -1) {
	338	ERR("could not create directory %s", tmp);
	339	free(tmp);
f99c0b5c	340	return NULL;
72ebd39a PMF	341	}
	342	free(tmp);
	343
ed1317e7 PMF	344	asprintf(&tmp, "%s/%u_%lld/%s_0", trace_path, buf->pid, buf->pidunique, buf->name);
ed1317e7 PMF	345	result = fd = open(tmp, O_WRONLY \| O_CREAT \| O_TRUNC \| O_EXCL, 00600);
3a7b90de PMF	346	if(result == -1) {
3a7b90de PMF	347	PERROR("open");
6cb88bc0	348	ERR("failed opening trace file %s", tmp);
f99c0b5c	349	return NULL;
3a7b90de PMF	350	}
	351	buf->file_fd = fd;
	352	free(tmp);
	353
3158b808 PMF	354	pthread_mutex_lock(&active_buffers_mutex);
	355	active_buffers++;
	356	pthread_mutex_unlock(&active_buffers_mutex);
	357
f99c0b5c PMF	358	return buf;
	359	}
	360
	361	int consumer_loop(struct buffer_info *buf)
	362	{
	363	int result;
	364
	365	pthread_cleanup_push(decrement_active_buffers, NULL);
	366
	367	for(;;) {
	368	/* get the subbuffer */
	369	result = get_subbuffer(buf);
	370	if(result == -1) {
	371	ERR("error getting subbuffer");
	372	continue;
	373	}
	374	else if(result == GET_SUBBUF_DONE) {
	375	/* this is done */
	376	break;
	377	}
	378	else if(result == GET_SUBBUF_DIED) {
	379	finish_consuming_dead_subbuffer(buf);
	380	break;
	381	}
	382
	383	/* write data to file */
	384	result = patient_write(buf->file_fd, buf->mem + (buf->consumed_old & (buf->n_subbufs * buf->subbuf_size-1)), buf->subbuf_size);
	385	if(result == -1) {
	386	PERROR("write");
	387	/* FIXME: maybe drop this trace */
	388	}
	389
	390	/* put the subbuffer */
	391	/* FIXME: we actually should unput the buffer before consuming... */
	392	result = put_subbuffer(buf);
	393	if(result == -1) {
	394	ERR("unknown error putting subbuffer (channel=%s)", buf->name);
	395	break;
	396	}
	397	else if(result == PUT_SUBBUF_PUSHED) {
	398	ERR("Buffer overflow (channel=%s), reader pushed. This channel will not be usable passed this point.", buf->name);
	399	break;
	400	}
	401	else if(result == PUT_SUBBUF_DIED) {
	402	WARN("application died while putting subbuffer");
	403	/* FIXME: probably need to skip the first subbuffer in finish_consuming_dead_subbuffer */
	404	finish_consuming_dead_subbuffer(buf);
	405	break;
	406	}
	407	else if(result == PUT_SUBBUF_OK) {
	408	}
	409	}
	410
	411	DBG("thread for buffer %s is stopping", buf->name);
	412
	413	/* FIXME: destroy, unalloc... */
	414
	415	pthread_cleanup_pop(1);
	416
	417	return 0;
	418	}
	419
	420	void free_buffer(struct buffer_info *buf)
	421	{
422	}
423
424	struct consumer_thread_args {
425	pid_t pid;
426	const char *bufname;
427	};
428
429	void consumer_thread(void arg)
430	{
431	struct buffer_info buf = (struct buffer_info ) arg;
432	struct consumer_thread_args args = (struct consumer_thread_args ) arg;
433
434	DBG("GOT ARGS: pid %d bufname %s", args->pid, args->bufname);
435
436	buf = connect_buffer(args->pid, args->bufname);
437	if(buf == NULL) {
438	ERR("failed to connect to buffer");
439	goto end;
440	}
441
442	consumer_loop(buf);
443
444	free_buffer(buf);
445
446	end:
447	/* bufname is free'd in free_buffer() */
448	free(args);
449	return NULL;
450	}
451
452	int start_consuming_buffer(pid_t pid, const char *bufname)
453	{
454	pthread_t thr;
455	struct consumer_thread_args *args;
456
457	DBG("beginning of start_consuming_buffer: args: pid %d bufname %s", pid, bufname);
458
459	args = (struct consumer_thread_args *) malloc(sizeof(struct consumer_thread_args));
460
461	args->pid = pid;
462	args->bufname = strdup(bufname);
463	DBG("beginning2 of start_consuming_buffer: args: pid %d bufname %s", args->pid, args->bufname);
464
465	pthread_create(&thr, NULL, consumer_thread, args);
466	DBG("end of start_consuming_buffer: args: pid %d bufname %s", args->pid, args->bufname);
3a7b90de PMF	467
	468	return 0;
	469	}
	470
cd226f25 PMF	471	void usage(void)
	472	{
	473	fprintf(stderr, "Usage:\nustd OPTIONS\n\nOptions:\n"
	474	"\t-h\t\tDisplay this usage.\n"
	475	"\t-o DIR\t\tSpecify the directory where to output the traces.\n"
	476	"\t-s PATH\t\tSpecify the path to use for the daemon socket.\n");
	477	}
	478
	479	int parse_args(int argc, char **argv)
	480	{
	481	int c;
	482
	483	while (1) {
	484	int option_index = 0;
	485	static struct option long_options[] = {
	486	{"help", 0, 0, 'h'},
	487	{"version", 0, 0, 'V'},
	488	{0, 0, 0, 0}
	489	};
	490
	491	c = getopt_long(argc, argv, "hs:o:", long_options, &option_index);
	492	if (c == -1)
	493	break;
	494
	495	switch (c) {
	496	case 0:
	497	printf("option %s", long_options[option_index].name);
	498	if (optarg)
	499	printf(" with arg %s", optarg);
	500	printf("\n");
	501	break;
	502	case 's':
	503	sock_path = optarg;
	504	break;
	505	case 'o':
	506	trace_path = optarg;
	507	if(!is_directory(trace_path)) {
	508	ERR("Not a valid directory. (%s)", trace_path);
	509	return -1;
	510	}
	511	break;
	512	case 'h':
	513	usage();
	514	exit(0);
	515	case 'V':
	516	printf("Version 0.0\n");
	517	break;
	518
	519	default:
	520	/* unknown option or other error; error is
	521	printed by getopt, just return */
	522	return -1;
	523	}
	524	}
	525
	526	return 0;
	527	}
	528
3158b808 PMF	529	void sigterm_handler(int sig)
	530	{
	531	terminate_req = 1;
	532	}
	533
3796af9b PMF	534	int main(int argc, char **argv)
	535	{
	536	struct ustcomm_ustd ustd;
	537	int result;
a3cdd4a7	538	sigset_t sigset;
3158b808 PMF	539	struct sigaction sa;
	540
	541	result = sigemptyset(&sigset);
	542	if(result == -1) {
4d70f833	543	PERROR("sigemptyset");
3158b808 PMF	544	return 1;
	545	}
	546	sa.sa_handler = sigterm_handler;
	547	sa.sa_mask = sigset;
	548	sa.sa_flags = SA_RESTART;
	549	result = sigaction(SIGTERM, &sa, NULL);
	550	if(result == -1) {
	551	PERROR("sigaction");
	552	return 1;
	553	}
3796af9b	554
cd226f25 PMF	555	result = parse_args(argc, argv);
	556	if(result == -1) {
	557	exit(1);
	558	}
	559
	560	result = ustcomm_init_ustd(&ustd, sock_path);
3796af9b PMF	561	if(result == -1) {
	562	ERR("failed to initialize socket");
	563	return 1;
	564	}
	565
3158b808	566	/* setup handler for SIGPIPE */
a3cdd4a7 PMF	567	result = sigemptyset(&sigset);
a3cdd4a7 PMF	568	if(result == -1) {
4d70f833	569	PERROR("sigemptyset");
a3cdd4a7 PMF	570	return 1;
	571	}
	572	result = sigaddset(&sigset, SIGPIPE);
	573	if(result == -1) {
4d70f833	574	PERROR("sigaddset");
a3cdd4a7 PMF	575	return 1;
	576	}
	577	result = sigprocmask(SIG_BLOCK, &sigset, NULL);
	578	if(result == -1) {
4d70f833	579	PERROR("sigprocmask");
a3cdd4a7 PMF	580	return 1;
	581	}
	582
688760ef	583	/* app loop */
3796af9b PMF	584	for(;;) {
	585	char *recvbuf;
	586
3a7b90de	587	/* check for requests on our public socket */
688760ef PMF	588	result = ustcomm_ustd_recv_message(&ustd, &recvbuf, NULL, 100);
	589	if(result == -1) {
	590	ERR("error in ustcomm_ustd_recv_message");
f99c0b5c	591	goto loop_end;
688760ef PMF	592	}
	593	if(result > 0) {
	594	if(!strncmp(recvbuf, "collect", 7)) {
	595	pid_t pid;
	596	char *bufname;
	597	int result;
3796af9b	598
688760ef PMF	599	result = sscanf(recvbuf, "%*s %d %50as", &pid, &bufname);
688760ef PMF	600	if(result != 2) {
f99c0b5c PMF	601	ERR("parsing error: %s", recvbuf);
f99c0b5c PMF	602	goto free_bufname;
688760ef	603	}
3796af9b	604
f99c0b5c	605	result = start_consuming_buffer(pid, bufname);
688760ef PMF	606	if(result < 0) {
688760ef PMF	607	ERR("error in add_buffer");
f99c0b5c	608	goto free_bufname;
688760ef	609	}
f99c0b5c PMF	610
	611	free_bufname:
	612	free(bufname);
3796af9b PMF	613	}
3796af9b PMF	614
688760ef	615	free(recvbuf);
3796af9b	616	}
3158b808	617
f99c0b5c PMF	618	loop_end:
f99c0b5c PMF	619
3158b808 PMF	620	if(terminate_req) {
	621	pthread_mutex_lock(&active_buffers_mutex);
	622	if(active_buffers == 0) {
	623	pthread_mutex_unlock(&active_buffers_mutex);
	624	break;
	625	}
	626	pthread_mutex_unlock(&active_buffers_mutex);
	627	}
3796af9b PMF	628	}
	629
	630	return 0;
	631	}