+/* 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 "localerr.h"
+#include "ustd.h"
+#include "usterr.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
+ */
-struct buffer_info {
- char *name;
- pid_t pid;
+#define GET_SUBBUF_OK 1
+#define GET_SUBBUF_DONE 0
+#define GET_SUBBUF_DIED 2
- int shmid;
- void *mem;
- int memlen;
+#define PUT_SUBBUF_OK 1
+#define PUT_SUBBUF_DIED 0
+#define PUT_SUBBUF_PUSHED 2
- int n_subbufs;
- int subbuf_size;
+char *sock_path=NULL;
+char *trace_path=NULL;
+int daemon_mode = 0;
+char *pidfile = NULL;
- int file_fd; /* output file */
+/* 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;
- struct list_head list;
+int get_subbuffer(struct buffer_info *buf)
+{
+ char *send_msg=NULL;
+ char *received_msg=NULL;
+ char *rep_code=NULL;
+ int retval;
+ int result;
- long consumed_old;
-};
+ 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;
+ }
-int add_buffer(pid_t pid, char *bufname)
+ return 1;
+}
+
+struct buffer_info *connect_buffer(pid_t pid, const char *bufname)
{
struct buffer_info *buf;
char *send_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 -1;
+ 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);
- send_message(pid, 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 NULL;
+ }
- result = sscanf(received_msg, "%d", &buf->shmid);
- if(result != 1) {
+ result = sscanf(received_msg, "%d %d", &buf->shmid, &buf->bufstruct_shmid);
+ if(result != 2) {
ERR("unable to parse response to get_shmid");
- return -1;
+ return NULL;
}
free(received_msg);
- DBG("got shmid %d", buf->shmid);
+ DBG("got shmids %d %d", buf->shmid, buf->bufstruct_shmid);
/* get n_subbufs */
asprintf(&send_msg, "get_n_subbufs %s", buf->name);
- send_message(pid, 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 NULL;
+ }
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);
- send_message(pid, send_msg, &received_msg);
+ 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 -1;
+ 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 -1;
+ 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;
}
- DBG("successfully attached memory");
+ buf->memlen = shmds.shm_segsz;
/* open file for output */
- asprintf(&tmp, "/tmp/trace/%s_0", buf->name);
- result = fd = open(tmp, O_WRONLY | O_CREAT | O_TRUNC, 00600);
+ 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");
- return -1;
+ ERR("failed opening trace file %s", tmp);
+ return NULL;
}
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);
- return 0;
+ return buf;
}
-int get_subbuffer(struct buffer_info *buf)
+int consumer_loop(struct buffer_info *buf)
{
- char *send_msg;
- char *received_msg;
- char *rep_code;
- int retval;
int result;
- asprintf(&send_msg, "get_subbuffer %s", buf->name);
- result = send_message(buf->pid, send_msg, &received_msg);
- if(result < 0) {
- ERR("get_subbuffer: send_message failed");
- return -1;
- }
- free(send_msg);
+ pthread_cleanup_push(decrement_active_buffers, NULL);
- result = sscanf(received_msg, "%as %ld", &rep_code, &buf->consumed_old);
- if(result != 2) {
- ERR("unable to parse response to get_subbuffer");
- return -1;
- }
- free(received_msg);
+ 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;
+ }
- if(!strcmp(rep_code, "OK")) {
- DBG("got subbuffer %s", buf->name);
- retval = 1;
- }
- else {
- DBG("did not get subbuffer %s", buf->name);
- retval = 0;
+ /* 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) {
+ }
}
- free(rep_code);
- return retval;
+ DBG("thread for buffer %s is stopping", buf->name);
+
+ /* FIXME: destroy, unalloc... */
+
+ pthread_cleanup_pop(1);
+
+ return 0;
}
-int put_subbuffer(struct buffer_info *buf)
+void free_buffer(struct buffer_info *buf)
{
- char *send_msg;
- char *received_msg;
- char *rep_code;
- int retval;
- int result;
+}
- asprintf(&send_msg, "put_subbuffer %s %ld", buf->name, buf->consumed_old);
- result = send_message(buf->pid, send_msg, &received_msg);
- if(result < 0) {
- ERR("put_subbuffer: send_message failed");
- return -1;
- }
- free(send_msg);
+struct consumer_thread_args {
+ pid_t pid;
+ const char *bufname;
+};
- result = sscanf(received_msg, "%as", &rep_code);
- if(result != 1) {
- ERR("unable to parse response to put_subbuffer");
- return -1;
- }
- free(received_msg);
+void *consumer_thread(void *arg)
+{
+ struct buffer_info *buf = (struct buffer_info *) arg;
+ struct consumer_thread_args *args = (struct consumer_thread_args *) arg;
- if(!strcmp(rep_code, "OK")) {
- DBG("subbuffer put %s", buf->name);
- retval = 1;
- }
- else {
- ERR("invalid response to put_subbuffer");
+ 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;
}
- free(rep_code);
- return retval;
+ consumer_loop(buf);
+
+ free_buffer(buf);
+
+ end:
+ /* bufname is free'd in free_buffer() */
+ free(args);
+ return NULL;
}
-ssize_t patient_write(int fd, const void *buf, size_t count)
+int start_consuming_buffer(pid_t pid, const char *bufname)
{
- const char *bufc = (const char *) buf;
- int result;
+ pthread_t thr;
+ struct consumer_thread_args *args;
- for(;;) {
- result = write(fd, bufc, count);
- if(result <= 0) {
- return result;
- }
- count -= result;
- bufc += result;
+ 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"
+ "\t-d\t\tStart as a daemon.\n"
+ "\t--pidfile FILE\tWrite the PID in this file (when using -d).\n");
+}
- if(count == 0) {
+int parse_args(int argc, char **argv)
+{
+ int c;
+
+ 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:d", 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 'd':
+ daemon_mode = 1;
+ break;
+ case 'p':
+ pidfile = strdup(optarg);
+ 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 bufc-(const char *)buf;
+ return 0;
}
-int main(int argc, char **argv)
+void sigterm_handler(int sig)
+{
+ terminate_req = 1;
+}
+
+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;
+ 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 = ustcomm_init_ustd(&ustd);
+ 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;
+ }
+
+ /* 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;
- struct buffer_info *buf;
- /* 1. check for requests on our public socket */
+ /* 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");
- 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);
}
free(recvbuf);
}
- /* 2. try to consume data from tracing apps */
- list_for_each_entry(buf, &buffers, list) {
- result = get_subbuffer(buf);
- if(result == -1) {
- ERR("error getting subbuffer");
- continue;
- }
- if(result == 0)
- continue;
-
- /* write data to file */
- //result = write(buf->file_fd, buf->, );
- 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 */
- }
+ loop_end:
- result = put_subbuffer(buf);
- if(result == -1) {
- ERR("error putting subbuffer");
+ 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;
+}
+
+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;
+}