X-Git-Url: http://git.lttng.org/?a=blobdiff_plain;f=ustd%2Fustd.c;h=fdf8d13f8d2f1fe418b1604a1b6baad3a1114fd1;hb=3158b808d3a8c45995ac7a40b022f9d569290b49;hp=ab4ec7aaac38c281f3c4cc6ac8f2c735453784ff;hpb=0b0cd93782698872ea4778d29cd68091663ca367;p=ust.git
diff --git a/ustd/ustd.c b/ustd/ustd.c
index ab4ec7a..fdf8d13 100644
--- a/ustd/ustd.c
+++ b/ustd/ustd.c
@@ -1,38 +1,41 @@
-/*
- * Copyright (C) 2009 Pierre-Marc Fournier
+/* Copyright (C) 2009 Pierre-Marc Fournier
*
- * This program is free software: you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation, either version 3 of the License, or
- * (at your option) any later version.
+ * 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 program is distributed in the hope that it will be useful,
+ * 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 General Public License for more details.
+ * 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 General Public License
- * along with this program. If not, see .
+ * 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
+#include
#include
#include
#include
#include
+#include
#include
#include
#include
+#include
+#include
+#include
#include "ustd.h"
#include "localerr.h"
#include "ustcomm.h"
-struct list_head buffers = LIST_HEAD_INIT(buffers);
-
/* return value: 0 = subbuffer is finished, it won't produce data anymore
* 1 = got subbuffer successfully
* <0 = error
@@ -42,6 +45,53 @@ struct list_head buffers = LIST_HEAD_INIT(buffers);
#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 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;
@@ -53,7 +103,11 @@ int get_subbuffer(struct buffer_info *buf)
asprintf(&send_msg, "get_subbuffer %s", buf->name);
result = ustcomm_send_request(&buf->conn, send_msg, &received_msg);
free(send_msg);
- if(result < 0) {
+ if(test_sigpipe()) {
+ WARN("process %d destroyed before we could connect to it", buf->pid);
+ return GET_SUBBUF_DONE;
+ }
+ else if(result < 0) {
ERR("get_subbuffer: ustcomm_send_request failed");
return -1;
}
@@ -113,16 +167,20 @@ int put_subbuffer(struct buffer_info *buf)
if(!strcmp(rep_code, "OK")) {
DBG("subbuffer put %s", buf->name);
- retval = 1;
+ retval = PUT_SUBBUF_OK;
}
else {
- ERR("invalid response to put_subbuffer");
+ DBG("put_subbuffer: received error, we were pushed");
+ return PUT_SUBBUF_PUSHED;
}
free(rep_code);
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;
@@ -144,11 +202,20 @@ ssize_t patient_write(int fd, const void *buf, size_t count)
return bufc-(const char *)buf;
}
+void decrement_active_buffers(void *arg)
+{
+ pthread_mutex_lock(&active_buffers_mutex);
+ active_buffers--;
+ 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);
@@ -175,18 +242,63 @@ void *consumer_thread(void *arg)
/* put the subbuffer */
result = put_subbuffer(buf);
if(result == -1) {
- ERR("error putting subbuffer");
+ 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);
+ }
+ 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;
+ 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;
+}
+
int add_buffer(pid_t pid, char *bufname)
{
struct buffer_info *buf;
@@ -196,6 +308,7 @@ int add_buffer(pid_t pid, char *bufname)
char *tmp;
int fd;
pthread_t thr;
+ struct shmid_ds shmds;
buf = (struct buffer_info *) malloc(sizeof(struct buffer_info));
if(buf == NULL) {
@@ -209,15 +322,18 @@ int add_buffer(pid_t pid, char *bufname)
/* connect to app */
result = ustcomm_connect_app(buf->pid, &buf->conn);
if(result) {
- ERR("unable to connect to process");
+ WARN("unable to connect to process, it probably died before we were able to connect");
return -1;
}
/* get shmid */
asprintf(&send_msg, "get_shmid %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);
- DBG("got buffer name %s", buf->name);
+ if(result == -1) {
+ ERR("problem in ustcomm_send_request(get_shmid)");
+ return -1;
+ }
result = sscanf(received_msg, "%d %d", &buf->shmid, &buf->bufstruct_shmid);
if(result != 2) {
@@ -229,8 +345,12 @@ int add_buffer(pid_t pid, char *bufname)
/* get n_subbufs */
asprintf(&send_msg, "get_n_subbufs %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(g_n_subbufs)");
+ return -1;
+ }
result = sscanf(received_msg, "%d", &buf->n_subbufs);
if(result != 1) {
@@ -268,34 +388,169 @@ int add_buffer(pid_t pid, char *bufname)
}
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 -1;
+ }
+ buf->memlen = shmds.shm_segsz;
+
/* open file for output */
- asprintf(&tmp, "/tmp/trace/%s_0", buf->name);
+ 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 -1;
+ }
+
+ trace_path = USTD_DEFAULT_TRACE_PATH;
+ }
+
+ asprintf(&tmp, "%s/%u", trace_path, buf->pid);
+ result = create_dir_if_needed(tmp);
+ if(result == -1) {
+ ERR("could not create directory %s", tmp);
+ free(tmp);
+ return -1;
+ }
+ free(tmp);
+
+ asprintf(&tmp, "%s/%u/%s_0", trace_path, buf->pid, buf->name);
result = fd = open(tmp, O_WRONLY | O_CREAT | O_TRUNC, 00600);
if(result == -1) {
PERROR("open");
+ ERR("failed opening trace file %s", tmp);
return -1;
}
buf->file_fd = fd;
free(tmp);
- //list_add(&buf->list, &buffers);
+ pthread_mutex_lock(&active_buffers_mutex);
+ active_buffers++;
+ pthread_mutex_unlock(&active_buffers_mutex);
pthread_create(&thr, NULL, consumer_thread, buf);
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 = ustcomm_init_ustd(&ustd);
+ 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;
@@ -326,6 +581,15 @@ int main(int argc, char **argv)
free(recvbuf);
}
+
+ 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;