X-Git-Url: http://git.lttng.org/?a=blobdiff_plain;f=ustd%2Fustd.c;h=18dbf6377a5488dbc0d3f322c7f0663791f1d81f;hb=5f9aacae75a4181a54bf16f31ce8e18229dddc60;hp=b3af3c47efd3700fcb026247577ce8741782e3eb;hpb=c39c72ee5890c7727ae2697f321ba1b3d6c862f5;p=ust.git

diff --git a/ustd/ustd.c b/ustd/ustd.c
index b3af3c4..18dbf63 100644
--- a/ustd/ustd.c
+++ b/ustd/ustd.c
@@ -1,4 +1,5 @@
 /* Copyright (C) 2009  Pierre-Marc Fournier
+ *               2010  Alexis Halle
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
@@ -18,10 +19,10 @@
 #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>
@@ -29,394 +30,469 @@
 #include <string.h>
 #include <errno.h>
 #include <assert.h>
+#include <getopt.h>
 
-#include "ustd.h"
-#include "localerr.h"
-#include "ustcomm.h"
+#include "libustd.h"
+#include "usterr.h"
 
-/* return value: 0 = subbuffer is finished, it won't produce data anymore
- *               1 = got subbuffer successfully
- *               <0 = error
- */
+char *sock_path=NULL;
+char *trace_path=NULL;
+int daemon_mode = 0;
+char *pidfile = NULL;
 
-#define GET_SUBBUF_OK 1
-#define GET_SUBBUF_DONE 0
-#define GET_SUBBUF_DIED 2
+struct libustd_instance *instance;
 
-#define PUT_SUBBUF_OK 1
-#define PUT_SUBBUF_DIED 0
-#define PUT_SUBBUF_PUSHED 2
+struct buffer_info_local {
+	/* output file */
+	int file_fd;
+	/* the offset we must truncate to, to unput the last subbuffer */
+	off_t previous_offset;
+};
 
-int test_sigpipe(void)
+static int write_pidfile(const char *file_name, pid_t pid)
 {
-	sigset_t sigset;
-	int result;
+	FILE *pidfp;
 
-	result = sigemptyset(&sigset);
-	if(result == -1) {
-		perror("sigemptyset");
+	pidfp = fopen(file_name, "w");
+	if(!pidfp) {
+		PERROR("fopen (%s)", file_name);
+		WARN("killing child process");
 		return -1;
 	}
-	result = sigaddset(&sigset, SIGPIPE);
+
+	fprintf(pidfp, "%d\n", pid);
+
+	fclose(pidfp);
+
+	return 0;
+}
+
+int create_dir_if_needed(char *dir)
+{
+	int result;
+	result = mkdir(dir, 0777);
 	if(result == -1) {
-		perror("sigaddset");
-		return -1;
+		if(errno != EEXIST) {
+			PERROR("mkdir");
+			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);
-	}
+	return 0;
 }
 
-int get_subbuffer(struct buffer_info *buf)
+int unwrite_last_subbuffer(struct buffer_info *buf)
 {
-	char *send_msg;
-	char *received_msg;
-	char *rep_code;
-	int retval;
 	int result;
+	struct buffer_info_local *buf_local = buf->user_data;
 
-	asprintf(&send_msg, "get_subbuffer %s", buf->name);
-	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");
+	result = ftruncate(buf_local->file_fd, buf_local->previous_offset);
+	if(result == -1) {
+		PERROR("ftruncate");
 		return -1;
 	}
-	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 && result != 1) {
-		ERR("unable to parse response to get_subbuffer");
+	result = lseek(buf_local->file_fd, buf_local->previous_offset, SEEK_SET);
+	if(result == (int)(off_t)-1) {
+		PERROR("lseek");
 		return -1;
 	}
 
-	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) {
-		return GET_SUBBUF_DONE;
-	}
-	else {
-		DBG("error getting subbuffer %s", buf->name);
-		retval = -1;
-	}
-
-	/* FIMXE: free correctly the stuff */
-	free(received_msg);
-	free(rep_code);
-	return retval;
+	return 0;
 }
 
-int put_subbuffer(struct buffer_info *buf)
+int write_current_subbuffer(struct buffer_info *buf)
 {
-	char *send_msg;
-	char *received_msg;
-	char *rep_code;
-	int retval;
 	int result;
+	struct buffer_info_local *buf_local = buf->user_data;
 
-	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) {
-		ERR("put_subbuffer: send_message failed");
-		return -1;
-	}
-	free(send_msg);
+	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);
 
-	result = sscanf(received_msg, "%as", &rep_code);
-	if(result != 1) {
-		ERR("unable to parse response to put_subbuffer");
+	off_t cur_offset = lseek(buf_local->file_fd, 0, SEEK_CUR);
+	if(cur_offset == (off_t)-1) {
+		PERROR("lseek");
 		return -1;
 	}
-	free(received_msg);
 
-	if(!strcmp(rep_code, "OK")) {
-		DBG("subbuffer put %s", buf->name);
-		retval = PUT_SUBBUF_OK;
-	}
-	else {
-		DBG("put_subbuffer: received error, we were pushed");
-		return PUT_SUBBUF_PUSHED;
+	buf_local->previous_offset = cur_offset;
+	DBG("previous_offset: %ld", cur_offset);
+
+	result = patient_write(buf_local->file_fd, subbuf_mem, cur_sb_size);
+	if(result == -1) {
+		PERROR("write");
+		return -1;
 	}
 
-	free(rep_code);
-	return retval;
+	return 0;
 }
 
-/* This write is patient because it restarts if it was incomplete.
- */
-
-ssize_t patient_write(int fd, const void *buf, size_t count)
+int on_read_subbuffer(struct libustd_callbacks *data, struct buffer_info *buf)
 {
-	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;
+	return write_current_subbuffer(buf);
 }
 
-void *consumer_thread(void *arg)
+int on_read_partial_subbuffer(struct libustd_callbacks *data, struct buffer_info *buf,
+				long subbuf_index, unsigned long valid_length)
 {
-	struct buffer_info *buf = (struct buffer_info *) arg;
+	struct buffer_info_local *buf_local = buf->user_data;
+	char *tmp;
 	int result;
+	unsigned long pad_size;
 
-	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 */
-		}
+	result = patient_write(buf_local->file_fd, buf->mem + subbuf_index * buf->subbuf_size, valid_length);
+	if(result == -1) {
+		ERR("Error writing to buffer file");
+		return;
+	}
 
-		/* put the subbuffer */
-		result = put_subbuffer(buf);
+	/* pad with empty bytes */
+	pad_size = PAGE_ALIGN(valid_length)-valid_length;
+	if(pad_size) {
+		tmp = malloc(pad_size);
+		memset(tmp, 0, pad_size);
+		result = patient_write(buf_local->file_fd, tmp, pad_size);
 		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) {
+			ERR("Error writing to buffer file");
+			return;
 		}
+		free(tmp);
 	}
 
-	DBG("thread for buffer %s is stopping", buf->name);
-
-	/* FIXME: destroy, unalloc... */
-
-	return NULL;
 }
 
-int add_buffer(pid_t pid, char *bufname)
+int on_open_buffer(struct libustd_callbacks *data, struct buffer_info *buf)
 {
-	struct buffer_info *buf;
-	char *send_msg;
-	char *received_msg;
-	int result;
 	char *tmp;
+	int result;
 	int fd;
-	pthread_t thr;
-	struct shmid_ds shmds;
+	struct buffer_info_local *buf_local =
+		malloc(sizeof(struct buffer_info_local));
 
-	buf = (struct buffer_info *) malloc(sizeof(struct buffer_info));
-	if(buf == NULL) {
-		ERR("add_buffer: insufficient memory");
-		return -1;
+	if(!buf_local) {
+		ERR("could not allocate buffer_info_local struct");
+		return 1;
 	}
 
-	buf->name = bufname;
-	buf->pid = pid;
+	buf->user_data = buf_local;
 
-	/* 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;
+	/* 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 1;
+		}
+
+		trace_path = USTD_DEFAULT_TRACE_PATH;
 	}
 
-	/* get shmid */
-	asprintf(&send_msg, "get_shmid %s", buf->name);
-	result = ustcomm_send_request(&buf->conn, send_msg, &received_msg);
-	free(send_msg);
+	asprintf(&tmp, "%s/%u_%lld", trace_path, buf->pid, buf->pidunique);
+	result = create_dir_if_needed(tmp);
 	if(result == -1) {
-		ERR("problem in ustcomm_send_request(get_shmid)");
-		return -1;
+		ERR("could not create directory %s", tmp);
+		free(tmp);
+		return 1;
 	}
+	free(tmp);
 
-	result = sscanf(received_msg, "%d %d", &buf->shmid, &buf->bufstruct_shmid);
-	if(result != 2) {
-		ERR("unable to parse response to get_shmid");
-		return -1;
+	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;
 	}
-	free(received_msg);
-	DBG("got shmids %d %d", buf->shmid, buf->bufstruct_shmid);
+	buf_local->file_fd = fd;
+	free(tmp);
+
+	return 0;
+}
 
-	/* 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);
+int on_close_buffer(struct libustd_callbacks *data, struct buffer_info *buf)
+{
+	struct buffer_info_local *buf_local = buf->user_data;
+	int result = close(buf_local->file_fd);
+	free(buf_local);
 	if(result == -1) {
-		ERR("problem in ustcomm_send_request(g_n_subbufs)");
-		return -1;
+		PERROR("close");
 	}
+	return 0;
+}
 
-	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);
+int on_put_error(struct libustd_callbacks *data, struct buffer_info *buf)
+{
+	unwrite_last_subbuffer(buf);
+}
 
-	/* get subbuf size */
-	asprintf(&send_msg, "get_subbuf_size %s", buf->name);
-	ustcomm_send_request(&buf->conn, send_msg, &received_msg);
-	free(send_msg);
+struct libustd_callbacks *new_callbacks()
+{
+	struct libustd_callbacks *callbacks =
+		malloc(sizeof(struct libustd_callbacks));
 
-	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);
+	if(!callbacks)
+		return NULL;
 
-	/* attach memory */
-	buf->mem = shmat(buf->shmid, NULL, 0);
-	if(buf->mem == (void *) 0) {
-		perror("shmat");
-		return -1;
-	}
-	DBG("successfully attached buffer memory");
+	callbacks->on_open_buffer = on_open_buffer;
+	callbacks->on_close_buffer = on_close_buffer;
+	callbacks->on_read_subbuffer = on_read_subbuffer;
+	callbacks->on_read_partial_subbuffer = on_read_partial_subbuffer;
+	callbacks->on_put_error = on_put_error;
+	callbacks->on_new_thread = NULL;
+	callbacks->on_close_thread = NULL;
+	callbacks->on_trace_end = NULL;
 
-	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");
+	return callbacks;
+
+}
+
+int is_directory(const char *dir)
+{
+	int result;
+	struct stat st;
 
-	/* obtain info on the memory segment */
-	result = shmctl(buf->shmid, IPC_STAT, &shmds);
+	result = stat(dir, &st);
 	if(result == -1) {
-		perror("shmctl");
-		return -1;
+		PERROR("stat");
+		return 0;
 	}
-	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;
+	if(!S_ISDIR(st.st_mode)) {
+		return 0;
 	}
-	buf->file_fd = fd;
-	free(tmp);
 
-	pthread_create(&thr, NULL, consumer_thread, buf);
+	return 1;
+}
+
+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");
+}
+
+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 0;
 }
 
-int main(int argc, char **argv)
+void sigterm_handler(int sig)
+{
+	libustd_stop_instance(instance, 0);
+}
+
+int start_ustd(int fd)
 {
-	struct ustcomm_ustd ustd;
 	int result;
 	sigset_t sigset;
+	struct sigaction sa;
 
-	result = ustcomm_init_ustd(&ustd);
+	struct libustd_callbacks *callbacks = new_callbacks();
+	if(!callbacks) {
+		PERROR("new_callbacks");
+		return 1;
+	}
+
+	result = sigemptyset(&sigset);
 	if(result == -1) {
-		ERR("failed to initialize socket");
+		PERROR("sigemptyset");
+		return 1;
+	}
+	sa.sa_handler = sigterm_handler;
+	sa.sa_mask = sigset;
+	sa.sa_flags = 0;
+	result = sigaction(SIGTERM, &sa, NULL);
+	if(result == -1) {
+		PERROR("sigaction");
+		return 1;
+	}
+	result = sigaction(SIGINT, &sa, NULL);
+	if(result == -1) {
+		PERROR("sigaction");
 		return 1;
 	}
 
+	instance = libustd_new_instance(callbacks, sock_path);
+	if(!instance) {
+		ERR("failed to create libustd instance");
+		return 1;
+	}
+
+	result = libustd_init_instance(instance);
+	if(result) {
+		ERR("failed to initialize libustd instance");
+		return 1;
+	}
+
+	/* setup handler for SIGPIPE */
 	result = sigemptyset(&sigset);
 	if(result == -1) {
-		perror("sigemptyset");
+		PERROR("sigemptyset");
 		return 1;
 	}
 	result = sigaddset(&sigset, SIGPIPE);
 	if(result == -1) {
-		perror("sigaddset");
+		PERROR("sigaddset");
 		return 1;
 	}
 	result = sigprocmask(SIG_BLOCK, &sigset, NULL);
 	if(result == -1) {
-		perror("sigprocmask");
+		PERROR("sigprocmask");
 		return 1;
 	}
 
-	/* app loop */
-	for(;;) {
-		char *recvbuf;
+	/* Write pidfile */
+	if(pidfile) {
+		result = write_pidfile(pidfile, getpid());
+		if(result == -1) {
+			ERR("failed to write pidfile");
+			return 1;
+		}
+	}
 
-		/* check for requests on our public socket */
-		result = ustcomm_ustd_recv_message(&ustd, &recvbuf, NULL, 100);
+	/* Notify parent that we are successfully started. */
+	if(fd != -1) {
+		/* write any one character */
+		result = write(fd, "!", 1);
 		if(result == -1) {
-			ERR("error in ustcomm_ustd_recv_message");
-			continue;
+			PERROR("write");
+			return -1;
 		}
-		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) {
-					fprintf(stderr, "parsing error: %s\n", recvbuf);
-				}
-
-				result = add_buffer(pid, bufname);
-				if(result < 0) {
-					ERR("error in add_buffer");
-					continue;
-				}
-			}
+		if(result != 1) {
+			ERR("Problem sending confirmation of daemon start to parent");
+			return -1;
+		}
+		result = close(fd);
+		if(result == -1) {
+			PERROR("close");
+		}
+	}
+
+	libustd_start_instance(instance);
+
+	free(callbacks);
+
+	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;
 
-			free(recvbuf);
+		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;
+}