[lttng-dev] [PATCH lttng-tools 08/10] Add environment variable to allow abort on error

[Mathieu Desnoyers]

The new environment variable LTTNG_ABORT_ON_ERROR allows each
lttng-tools program to call abort() on PERROR() and ERR() after the
error message has been printed to stderr.

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers at efficios.com>
---
 doc/man/common-cmd-footer.txt |  3 +++
 doc/man/lttng-relayd.8.txt    |  3 +++
 doc/man/lttng-sessiond.8.txt  |  2 ++
 src/common/error.c            | 28 ++++++++++++++++++++++++++++
 src/common/error.h            |  5 +++++
 5 files changed, 41 insertions(+)

diff --git a/doc/man/common-cmd-footer.txt b/doc/man/common-cmd-footer.txt
index d776cc4..8b1b66f 100644
--- a/doc/man/common-cmd-footer.txt
+++ b/doc/man/common-cmd-footer.txt
@@ -19,6 +19,9 @@ ENVIRONMENT VARIABLES
 The genoption:--sessiond-path option has precedence over this
 environment variable.
 
+`LTTNG_ABORT_ON_ERROR`::
+    Abort process after the first error is encountered.
+
 Note that the man:lttng-create(1) command can spawn an LTTng
 session daemon automatically if none is running. See
 man:lttng-sessiond(8) for the environment variables influencing
diff --git a/doc/man/lttng-relayd.8.txt b/doc/man/lttng-relayd.8.txt
index d667be1..d3e5b3e 100644
--- a/doc/man/lttng-relayd.8.txt
+++ b/doc/man/lttng-relayd.8.txt
@@ -159,6 +159,9 @@ ENVIRONMENT VARIABLES
 `LTTNG_RELAYD_HEALTH`::
     Path to relay daemon health's socket.
 
+`LTTNG_ABORT_ON_ERROR`::
+    Abort the relay daemon after the first error is encountered.
+
 
 FILES
 -----
diff --git a/doc/man/lttng-sessiond.8.txt b/doc/man/lttng-sessiond.8.txt
index f4348d8..949d566 100644
--- a/doc/man/lttng-sessiond.8.txt
+++ b/doc/man/lttng-sessiond.8.txt
@@ -275,6 +275,8 @@ The option:--kmod-probes option overrides this variable.
 `LTTNG_SESSION_CONFIG_XSD_PATH`::
     Tracing session configuration XML schema definition (XSD) path.
 
+`LTTNG_ABORT_ON_ERROR`::
+    Abort the session daemon after the first error is encountered.
 
 FILES
 -----
diff --git a/src/common/error.c b/src/common/error.c
index f7e11e1..84bc04f 100644
--- a/src/common/error.c
+++ b/src/common/error.c
@@ -18,14 +18,23 @@
 #define _LGPL_SOURCE
 #include <assert.h>
 #include <inttypes.h>
+#include <stdlib.h>
+#include <string.h>
 
 #include <lttng/lttng-error.h>
 #include <common/common.h>
+#include <common/compat/getenv.h>
 
 #include "error.h"
 
 #define ERROR_INDEX(code) (code - LTTNG_OK)
 
+/*
+ * lttng_opt_abort_on_error: unset: -1, disabled: 0, enabled: 1.
+ * Controlled by the LTTNG_ABORT_ON_ERROR environment variable.
+ */
+static int lttng_opt_abort_on_error = -1;
+
 /* TLS variable that contains the time of one single log entry. */
 DEFINE_URCU_TLS(struct log_time, error_log_time);
 
@@ -196,3 +205,22 @@ const char *error_get_str(int32_t code)
 
 	return error_string_array[ERROR_INDEX(code)];
 }
+
+LTTNG_HIDDEN
+void lttng_abort_on_error(void)
+{
+	if (lttng_opt_abort_on_error < 0) {
+		/* Use lttng_secure_getenv() to query its state. */
+		const char *value;
+
+		value = lttng_secure_getenv("LTTNG_ABORT_ON_ERROR");
+		if (value && !strcmp(value, "1")) {
+			lttng_opt_abort_on_error = 1;
+		} else {
+			lttng_opt_abort_on_error = 0;
+		}
+	}
+	if (lttng_opt_abort_on_error > 0) {
+		abort();
+	}
+}
diff --git a/src/common/error.h b/src/common/error.h
index 9c9d2a7..6c239fe 100644
--- a/src/common/error.h
+++ b/src/common/error.h
@@ -89,6 +89,9 @@ extern int lttng_opt_mi;
 				((type) & (PRINT_WARN | PRINT_ERR | PRINT_BUG))) { \
 			fprintf(stderr, fmt, ## args);                             \
 		}                                                                  \
+		if ((type) & (PRINT_ERR | PRINT_BUG)) {                            \
+			lttng_abort_on_error();                                    \
+		}                                                                  \
 	} while (0);
 
 /* Three level of debug. Use -v, -vv or -vvv for the levels */
@@ -174,4 +177,6 @@ const char *error_get_str(int32_t code);
  */
 const char *log_add_time();
 
+void lttng_abort_on_error(void);
+
 #endif /* _ERROR_H */
-- 
2.1.4