libctdb: test: logging enhancement

Make children log through a pipe to the parent, which then spits it out
only if the child has a problem.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>


(This used to be ctdb commit 8ac006cf6c6cbfd3fe1606178eb0f0127d33f632)

4 files changed, 35 insertions, 20 deletions

diff --git a/ctdb/libctdb/test/failtest.c b/ctdb/libctdb/test/failtest.c
index 2560e3e5eba..d42ab057094 100644
--- a/ctdb/libctdb/test/failtest.c
+++ b/ctdb/libctdb/test/failtest.c
@@ -22,6 +22,7 @@ Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 #include "tui.h"
 #include "log.h"
 #include "failtest.h"
+#include "ctdb-test.h"
 #include "talloc.h"
 #include "dlinklist.h"
 #include <stdlib.h>
@@ -229,8 +230,10 @@ bool should_i_fail_once(const char *location)
 bool should_i_fail(const char *func)
 {
 	pid_t child;
-	int status;
+	int status, pfd[2];
 	struct fail_decision *dec;
+	size_t log_size;
+	char *log;
 
 	if (failpath)
 		return do_failpath(func);
@@ -253,6 +256,9 @@ bool should_i_fail(const char *func)
 
 	DLIST_ADD_END(decisions, dec, struct fail_decision);
 
+	if (pipe(pfd) != 0)
+		err(1, "pipe failed for failtest!");
+
 	fflush(stdout);
 	child = fork();
 	if (child == -1)
@@ -261,6 +267,10 @@ bool should_i_fail(const char *func)
 	/* The child actually fails.  The script will screw up at this
 	 * point, but should not crash. */
 	if (child == 0) {
+		/* Log to parent (including stderr if things go really bad). */
+		close(pfd[0]);
+		dup2(pfd[1], STDOUT_FILENO);
+		dup2(pfd[1], STDERR_FILENO);
 		dec->failed = true;
 		if (!failtest_no_report || !strstr(func, failtest_no_report))
 			fails++;
@@ -268,6 +278,10 @@ bool should_i_fail(const char *func)
 	}
 
 	dec->failed = false;
+
+	close(pfd[1]);
+	log = grab_fd(pfd[0], &log_size);
+
 	while (waitpid(child, &status, 0) < 0) {
 		if (errno != EINTR)
 			err(1, "failtest waitpid failed for child %i",
@@ -276,19 +290,20 @@ bool should_i_fail(const char *func)
 
 	/* If child succeeded, or mere script failure, continue. */
 	if (WIFEXITED(status) && (WEXITSTATUS(status) == EXIT_SUCCESS
-				  || WEXITSTATUS(status) == EXIT_SCRIPTFAIL))
+				  || WEXITSTATUS(status) == EXIT_SCRIPTFAIL)) {
+		talloc_free(log);
 		return false;
-
-	/* Report unless child already reported it. */
-	if (!WIFEXITED(status) || WEXITSTATUS(status) != EXIT_SILENT) {
-		/* Reproduce child's path */
-		dec->failed = true;
-		log_line(LOG_ALWAYS, "Child %s %i on failure path: %s",
-			 WIFEXITED(status) ? "exited" : "signalled",
-			 WIFEXITED(status) ? WEXITSTATUS(status)
-			 : WTERMSIG(status), failpath_string());
 	}
-	exit(EXIT_SILENT);
+
+	/* Reproduce child's path */
+	dec->failed = true;
+
+	log_line(LOG_ALWAYS, "Child %s %i on failure path: %s",
+		 WIFEXITED(status) ? "exited" : "signalled",
+		 WIFEXITED(status) ? WEXITSTATUS(status)
+		 : WTERMSIG(status), failpath_string());
+	log_line(LOG_ALWAYS, "Child output:\n%s", log);
+	exit(EXIT_FAILURE);
 }
 
 void dump_failinfo(void)
diff --git a/ctdb/libctdb/test/log.c b/ctdb/libctdb/test/log.c
index a4a9be62b85..c8293be8f6f 100644
--- a/ctdb/libctdb/test/log.c
+++ b/ctdb/libctdb/test/log.c
@@ -26,6 +26,7 @@ Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 #include "expect.h"
 #include <string.h>
 #include <talloc.h>
+#include <err.h>
 
 static struct {
 	enum log_type	type;
@@ -37,7 +38,6 @@ static struct {
 	{ LOG_VERBOSE,	"verbose" },
 };
 
-static FILE *logstream;
 static int typemask = ~LOG_VERBOSE;
 
 bool log_line(enum log_type type, const char *format, ...)
@@ -50,8 +50,10 @@ bool log_line(enum log_type type, const char *format, ...)
 	line = talloc_vasprintf(NULL, format, ap);
 	va_end(ap);
 
-	if (!type || (type & typemask))
-		fprintf(logstream ?: stderr, "%s\n", line);
+	if (!type || (type & typemask)) {
+		printf("%s\n", line);
+		fflush(stdout);
+	}
 
 	ret = expect_log_hook(line);
 	talloc_free(line);
@@ -69,8 +71,9 @@ static void log_partial_v(enum log_type type,
 
 	/* write to the end of buffer */
 	if (vsnprintf(buf + len, bufsize - len - 1, format, ap)
-			> bufsize - len - 1)
-		log_line(LOG_ALWAYS, "log_line_partial buffer is full!");
+	    > bufsize - len - 1) {
+		errx(1, "log_line_partial buffer is full!");
+	}
 
 	ptr = buf;
 
@@ -222,7 +225,6 @@ static void log_admin_help(int agc, char **argv)
 
 static void log_init(void)
 {
-	logstream = stdout;
 	if (tui_quiet)
 		typemask = 0;
 	tui_register_command("log", log_admin, log_admin_help);
diff --git a/ctdb/libctdb/test/log.h b/ctdb/libctdb/test/log.h
index d19d6b2f5c0..068dd55543b 100644
--- a/ctdb/libctdb/test/log.h
+++ b/ctdb/libctdb/test/log.h
@@ -44,5 +44,4 @@ bool log_line(enum log_type type, const char *format, ...);
 /* Builds up buffer and prints out line at a time. */
 void log_partial(enum log_type type, char *buf, unsigned bufsize,
 		 const char *format, ...);
-
 #endif /* __HAVE_LOG_H */
diff --git a/ctdb/libctdb/test/utils.h b/ctdb/libctdb/test/utils.h
index eb849135895..c8ba7cee739 100644
--- a/ctdb/libctdb/test/utils.h
+++ b/ctdb/libctdb/test/utils.h
@@ -56,7 +56,6 @@ static inline bool strends(const char *a, const char *b)
 enum exitcodes {
 	/* EXIT_SUCCESS, EXIT_FAILURE is in stdlib.h */
 	EXIT_SCRIPTFAIL = EXIT_FAILURE + 1,
-	EXIT_SILENT,
 };
 
 /* init code */