X-Git-Url: http://git.efficios.com/?a=blobdiff_plain;f=src%2Flib%2Flttng-ctl%2Flttng-ctl.c;h=b6487b7c25f51c490ecb3f3bf28343244a6b680d;hb=44a5e5eb99f1d8b528f83fda5585677a3882f5f5;hp=a05a8049ec5dd7186fe83fa01ce83478a41f392f;hpb=00e2e675d54dc726a7c8f8887c889cc8ef022003;p=lttng-tools.git

diff --git a/src/lib/lttng-ctl/lttng-ctl.c b/src/lib/lttng-ctl/lttng-ctl.c
index a05a8049e..b6487b7c2 100644
--- a/src/lib/lttng-ctl/lttng-ctl.c
+++ b/src/lib/lttng-ctl/lttng-ctl.c
@@ -20,6 +20,7 @@
  */
 
 #define _GNU_SOURCE
+#include <assert.h>
 #include <grp.h>
 #include <errno.h>
 #include <stdio.h>
@@ -32,9 +33,30 @@
 #include <common/sessiond-comm/sessiond-comm.h>
 #include <lttng/lttng.h>
 
+#include "filter-parser.h"
+#include "filter-ast.h"
+#include "filter-bytecode.h"
+#include "memstream.h"
+
+#ifdef DEBUG
+const int print_xml = 1;
+#define dbg_printf(fmt, args...)	\
+	printf("[debug liblttng-ctl] " fmt, ## args)
+#else
+const int print_xml = 0;
+#define dbg_printf(fmt, args...)				\
+do {								\
+	/* do nothing but check printf format */		\
+	if (0)							\
+		printf("[debug liblttnctl] " fmt, ## args);	\
+} while (0)
+#endif
+
+
 /* Socket to session daemon for communication */
 static int sessiond_socket;
 static char sessiond_sock_path[PATH_MAX];
+static char health_sock_path[PATH_MAX];
 
 /* Variables */
 static char *tracing_group;
@@ -114,6 +136,31 @@ end:
 	return ret;
 }
 
+/*
+ * Send var len data to the session daemon.
+ *
+ * On success, returns the number of bytes sent (>=0)
+ * On error, returns -1
+ */
+static int send_session_varlen(void *data, size_t len)
+{
+	int ret;
+
+	if (!connected) {
+		ret = -ENOTCONN;
+		goto end;
+	}
+	if (!data || !len) {
+		ret = 0;
+		goto end;
+	}
+
+	ret = lttcomm_send_unix_sock(sessiond_socket, data, len);
+
+end:
+	return ret;
+}
+
 /*
  * Receive data from the sessiond socket.
  *
@@ -311,10 +358,14 @@ static int disconnect_sessiond(void)
 
 /*
  * Ask the session daemon a specific command and put the data into buf.
+ * Takes extra var. len. data as input to send to the session daemon.
  *
  * Return size of data (only payload, not header) or a negative error code.
  */
-static int ask_sessiond(struct lttcomm_session_msg *lsm, void **buf)
+static int ask_sessiond_varlen(struct lttcomm_session_msg *lsm,
+		void *vardata,
+		size_t varlen,
+		void **buf)
 {
 	int ret;
 	size_t size;
@@ -331,6 +382,11 @@ static int ask_sessiond(struct lttcomm_session_msg *lsm, void **buf)
 	if (ret < 0) {
 		goto end;
 	}
+	/* Send var len data */
+	ret = send_session_varlen(vardata, varlen);
+	if (ret < 0) {
+		goto end;
+	}
 
 	/* Get header from data transmission */
 	ret = recv_data_sessiond(&llm, sizeof(llm));
@@ -381,6 +437,16 @@ end:
 	return ret;
 }
 
+/*
+ * Ask the session daemon a specific command and put the data into buf.
+ *
+ * Return size of data (only payload, not header) or a negative error code.
+ */
+static int ask_sessiond(struct lttcomm_session_msg *lsm, void **buf)
+{
+	return ask_sessiond_varlen(lsm, NULL, 0, buf);
+}
+
 /*
  * Create lttng handle and return pointer.
  * The returned pointer will be NULL in case of malloc() error.
@@ -555,6 +621,139 @@ int lttng_enable_event(struct lttng_handle *handle,
 	return ask_sessiond(&lsm, NULL);
 }
 
+/*
+ * set filter for an event
+ * Return negative error value on error.
+ * Return size of returned session payload data if OK.
+ */
+
+int lttng_set_event_filter(struct lttng_handle *handle,
+		const char *event_name, const char *channel_name,
+		const char *filter_expression)
+{
+	struct lttcomm_session_msg lsm;
+	struct filter_parser_ctx *ctx;
+	FILE *fmem;
+	int ret = 0;
+
+	/* Safety check. */
+	if (handle == NULL) {
+		return -1;
+	}
+
+	if (!filter_expression) {
+		return 0;
+	}
+
+	/*
+	 * casting const to non-const, as the underlying function will
+	 * use it in read-only mode.
+	 */
+	fmem = lttng_fmemopen((void *) filter_expression,
+			strlen(filter_expression), "r");
+	if (!fmem) {
+		fprintf(stderr, "Error opening memory as stream\n");
+		return -ENOMEM;
+	}
+	ctx = filter_parser_ctx_alloc(fmem);
+	if (!ctx) {
+		fprintf(stderr, "Error allocating parser\n");
+		ret = -ENOMEM;
+		goto alloc_error;
+	}
+	ret = filter_parser_ctx_append_ast(ctx);
+	if (ret) {
+		fprintf(stderr, "Parse error\n");
+		ret = -EINVAL;
+		goto parse_error;
+	}
+	ret = filter_visitor_set_parent(ctx);
+	if (ret) {
+		fprintf(stderr, "Set parent error\n");
+		ret = -EINVAL;
+		goto parse_error;
+	}
+	if (print_xml) {
+		ret = filter_visitor_print_xml(ctx, stdout, 0);
+		if (ret) {
+			fflush(stdout);
+			fprintf(stderr, "XML print error\n");
+			ret = -EINVAL;
+			goto parse_error;
+		}
+	}
+
+	dbg_printf("Generating IR... ");
+	fflush(stdout);
+	ret = filter_visitor_ir_generate(ctx);
+	if (ret) {
+		fprintf(stderr, "Generate IR error\n");
+		ret = -EINVAL;
+		goto parse_error;
+	}
+	dbg_printf("done\n");
+
+	dbg_printf("Validating IR... ");
+	fflush(stdout);
+	ret = filter_visitor_ir_check_binary_op_nesting(ctx);
+	if (ret) {
+		ret = -EINVAL;
+		goto parse_error;
+	}
+	dbg_printf("done\n");
+
+	dbg_printf("Generating bytecode... ");
+	fflush(stdout);
+	ret = filter_visitor_bytecode_generate(ctx);
+	if (ret) {
+		fprintf(stderr, "Generate bytecode error\n");
+		ret = -EINVAL;
+		goto parse_error;
+	}
+	dbg_printf("done\n");
+	dbg_printf("Size of bytecode generated: %u bytes.\n",
+		bytecode_get_len(&ctx->bytecode->b));
+
+	memset(&lsm, 0, sizeof(lsm));
+
+	lsm.cmd_type = LTTNG_SET_FILTER;
+
+	/* Copy channel name */
+	copy_string(lsm.u.filter.channel_name, channel_name,
+			sizeof(lsm.u.filter.channel_name));
+	/* Copy event name */
+	copy_string(lsm.u.filter.event_name, event_name,
+			sizeof(lsm.u.filter.event_name));
+	lsm.u.filter.bytecode_len = sizeof(ctx->bytecode->b)
+			+ bytecode_get_len(&ctx->bytecode->b);
+
+	copy_lttng_domain(&lsm.domain, &handle->domain);
+
+	copy_string(lsm.session.name, handle->session_name,
+			sizeof(lsm.session.name));
+
+	ret = ask_sessiond_varlen(&lsm, &ctx->bytecode->b,
+				lsm.u.filter.bytecode_len, NULL);
+
+	filter_bytecode_free(ctx);
+	filter_ir_free(ctx);
+	filter_parser_ctx_free(ctx);
+	if (fclose(fmem) != 0) {
+		perror("fclose");
+	}
+	return ret;
+
+parse_error:
+	filter_bytecode_free(ctx);
+	filter_ir_free(ctx);
+	filter_parser_ctx_free(ctx);
+alloc_error:
+	if (fclose(fmem) != 0) {
+		perror("fclose");
+	}
+	return ret;
+}
+
 /*
  *  Disable event(s) of a channel and domain.
  *  If no event name is specified, all events are disabled.
@@ -1081,6 +1280,98 @@ int lttng_disable_consumer(struct lttng_handle *handle)
 	return ask_sessiond(&lsm, NULL);
 }
 
+/*
+ * Set health socket path by putting it in the global health_sock_path
+ * variable.
+ *
+ * Returns 0 on success or assert(0) on ENOMEM.
+ */
+static int set_health_socket_path(void)
+{
+	int ret;
+	int in_tgroup = 0;	/* In tracing group */
+	uid_t uid;
+	const char *home;
+
+	uid = getuid();
+
+	if (uid != 0) {
+		/* Are we in the tracing group ? */
+		in_tgroup = check_tracing_group(tracing_group);
+	}
+
+	if ((uid == 0) || in_tgroup) {
+		copy_string(health_sock_path, DEFAULT_GLOBAL_HEALTH_UNIX_SOCK,
+				sizeof(health_sock_path));
+	}
+
+	if (uid != 0) {
+		/*
+		 * With GNU C <  2.1, snprintf returns -1 if the target buffer is too small;
+		 * With GNU C >= 2.1, snprintf returns the required size (excluding closing null)
+		 */
+		home = getenv("HOME");
+		if (home == NULL) {
+			/* Fallback in /tmp .. */
+			home = "/tmp";
+		}
+
+		ret = snprintf(health_sock_path, sizeof(health_sock_path),
+				DEFAULT_HOME_HEALTH_UNIX_SOCK, home);
+		if ((ret < 0) || (ret >= sizeof(health_sock_path))) {
+			/* ENOMEM at this point... just kill the control lib. */
+			assert(0);
+		}
+	}
+
+	return 0;
+}
+
+/*
+ * Check session daemon health for a specific health component.
+ *
+ * Return 0 if health is OK or else 1 if BAD. A return value of -1 indicate
+ * that the control library was not able to connect to the session daemon
+ * health socket.
+ *
+ * Any other positive value is an lttcomm error which can be translate with
+ * lttng_strerror().
+ */
+int lttng_health_check(enum lttng_health_component c)
+{
+	int sock, ret;
+	struct lttcomm_health_msg msg;
+	struct lttcomm_health_data reply;
+
+	/* Connect to the sesssion daemon */
+	sock = lttcomm_connect_unix_sock(health_sock_path);
+	if (sock < 0) {
+		ret = -1;
+		goto error;
+	}
+
+	msg.cmd = LTTNG_HEALTH_CHECK;
+	msg.component = c;
+
+	ret = lttcomm_send_unix_sock(sock, (void *)&msg, sizeof(msg));
+	if (ret < 0) {
+		goto close_error;
+	}
+
+	ret = lttcomm_recv_unix_sock(sock, (void *)&reply, sizeof(reply));
+	if (ret < 0) {
+		goto close_error;
+	}
+
+	ret = reply.ret_code;
+
+close_error:
+	close(sock);
+
+error:
+	return ret;
+}
+
 /*
  * lib constructor
  */
@@ -1088,4 +1379,6 @@ static void __attribute__((constructor)) init()
 {
 	/* Set default session group */
 	lttng_set_tracing_group(DEFAULT_TRACING_GROUP);
+	/* Set socket for health check */
+	(void) set_health_socket_path();
 }