+/* 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/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 "ustd.h"
#include "localerr.h"
#include "ustcomm.h"
-struct list_head buffers = LIST_HEAD_INIT(buffers);
-
-struct buffer_info {
- char *name;
- pid_t pid;
-
- int shmid;
- void *mem;
- int memlen;
-
- int n_subbufs;
- int subbuf_size;
+/* return value: 0 = subbuffer is finished, it won't produce data anymore
+ * 1 = got subbuffer successfully
+ * <0 = error
+ */
- int file_fd; /* output file */
+#define GET_SUBBUF_OK 1
+#define GET_SUBBUF_DONE 0
+#define GET_SUBBUF_DIED 2
- struct list_head list;
+#define PUT_SUBBUF_OK 1
+#define PUT_SUBBUF_DIED 0
+#define PUT_SUBBUF_PUSHED 2
- long consumed_old;
-};
-
-int add_buffer(pid_t pid, char *bufname)
+int test_sigpipe(void)
{
- struct buffer_info *buf;
- char *send_msg;
- char *received_msg;
+ sigset_t sigset;
int result;
- char *tmp;
- int fd;
- buf = (struct buffer_info *) malloc(sizeof(struct buffer_info));
- if(buf == NULL) {
- ERR("add_buffer: insufficient memory");
+ result = sigemptyset(&sigset);
+ if(result == -1) {
+ perror("sigemptyset");
return -1;
}
-
- buf->name = bufname;
- buf->pid = pid;
-
- /* get shmid */
- asprintf(&send_msg, "get_shmid %s", buf->name);
- send_message(pid, send_msg, &received_msg);
- free(send_msg);
- DBG("got buffer name %s", buf->name);
-
- result = sscanf(received_msg, "%d", &buf->shmid);
- if(result != 1) {
- ERR("unable to parse response to get_shmid");
+ result = sigaddset(&sigset, SIGPIPE);
+ if(result == -1) {
+ perror("sigaddset");
return -1;
}
- free(received_msg);
- DBG("got shmid %d", buf->shmid);
- /* get n_subbufs */
- asprintf(&send_msg, "get_n_subbufs %s", buf->name);
- send_message(pid, send_msg, &received_msg);
- free(send_msg);
-
- result = sscanf(received_msg, "%d", &buf->n_subbufs);
- if(result != 1) {
- ERR("unable to parse response to get_n_subbufs");
- return -1;
+ result = sigtimedwait(&sigset, NULL, &(struct timespec){0,0});
+ if(result == -1 && errno == EAGAIN) {
+ /* no signal received */
+ return 0;
}
- 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);
- free(send_msg);
-
- result = sscanf(received_msg, "%d", &buf->subbuf_size);
- if(result != 1) {
- ERR("unable to parse response to get_subbuf_size");
+ else if(result == -1) {
+ perror("sigtimedwait");
return -1;
}
- 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;
+ else if(result == SIGPIPE) {
+ /* received sigpipe */
+ return 1;
}
- DBG("successfully attached memory");
-
- /* open file for output */
- asprintf(&tmp, "/tmp/trace/%s_0", buf->name);
- result = fd = open(tmp, O_WRONLY | O_CREAT | O_TRUNC, 00600);
- if(result == -1) {
- PERROR("open");
- return -1;
+ else {
+ assert(0);
}
- buf->file_fd = fd;
- free(tmp);
-
- list_add(&buf->list, &buffers);
-
- return 0;
}
int get_subbuffer(struct buffer_info *buf)
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");
+ result = ustcomm_send_request(&buf->conn, send_msg, &received_msg);
+ free(send_msg);
+ 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;
}
- free(send_msg);
+ else if(result == 0) {
+ DBG("app died while being traced");
+ return GET_SUBBUF_DIED;
+ }
result = sscanf(received_msg, "%as %ld", &rep_code, &buf->consumed_old);
- if(result != 2) {
+ if(result != 2 && result != 1) {
ERR("unable to parse response to get_subbuffer");
return -1;
}
- free(received_msg);
+
+ DBG("received msg is %s", received_msg);
if(!strcmp(rep_code, "OK")) {
DBG("got subbuffer %s", buf->name);
- retval = 1;
+ retval = GET_SUBBUF_OK;
+ }
+ else if(nth_token_is(received_msg, "END", 0) == 1) {
+ return GET_SUBBUF_DONE;
}
else {
- DBG("did not get subbuffer %s", buf->name);
- retval = 0;
+ DBG("error getting subbuffer %s", buf->name);
+ retval = -1;
}
+ /* FIMXE: free correctly the stuff */
+ free(received_msg);
free(rep_code);
return retval;
}
int result;
asprintf(&send_msg, "put_subbuffer %s %ld", buf->name, buf->consumed_old);
- result = send_message(buf->pid, send_msg, &received_msg);
+ result = ustcomm_send_request(&buf->conn, send_msg, &received_msg);
if(result < 0) {
ERR("put_subbuffer: send_message failed");
return -1;
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;
return bufc-(const char *)buf;
}
+void *consumer_thread(void *arg)
+{
+ struct buffer_info *buf = (struct buffer_info *) arg;
+ int result;
+
+ 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);
+ }
+ else if(result == PUT_SUBBUF_OK) {
+ }
+ }
+
+ DBG("thread for buffer %s is stopping", buf->name);
+
+ /* FIXME: destroy, unalloc... */
+
+ return NULL;
+}
+
+int add_buffer(pid_t pid, char *bufname)
+{
+ struct buffer_info *buf;
+ char *send_msg;
+ char *received_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;
+ }
+
+ 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 -1;
+ }
+
+ /* 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 -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;
+ }
+ 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 -1;
+ }
+
+ result = sscanf(received_msg, "%d", &buf->n_subbufs);
+ if(result != 1) {
+ ERR("unable to parse response to get_n_subbufs");
+ return -1;
+ }
+ 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 -1;
+ }
+ 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;
+ }
+ DBG("successfully attached buffer memory");
+
+ buf->bufstruct_mem = shmat(buf->bufstruct_shmid, NULL, 0);
+ if(buf->bufstruct_mem == (void *) 0) {
+ perror("shmat");
+ return -1;
+ }
+ 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);
+ 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);
+
+ pthread_create(&thr, NULL, consumer_thread, buf);
+
+ return 0;
+}
+
int main(int argc, char **argv)
{
struct ustcomm_ustd ustd;
int result;
+ sigset_t sigset;
result = ustcomm_init_ustd(&ustd);
if(result == -1) {
return 1;
}
+ 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;
- 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");
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 */
- }
-
- result = put_subbuffer(buf);
- if(result == -1) {
- ERR("error putting subbuffer");
- }
- }
}
return 0;
projects / ust.git / blobdiff