Tests: Add callstack contexts tests

[lttng-tools.git] / tests / utils / testapp / gen-syscall-events-callstack / gen-syscall-events-callstack.c

diff --git a/tests/utils/testapp/gen-syscall-events-callstack/gen-syscall-events-callstack.c b/tests/utils/testapp/gen-syscall-events-callstack/gen-syscall-events-callstack.c
new file mode 100644 (file)
index 0000000..48210fa
--- /dev/null
+++ b/tests/utils/testapp/gen-syscall-events-callstack/gen-syscall-events-callstack.c
@@ -0,0 +1,118 @@
+/*
+ * Copyright (C) - 2017 Francis Deslauriers <francis.deslauriers@efficios.com>
+ *
+ * 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; version 2.1 of the License.
+ *
+ * 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
+ */
+
+#include <fcntl.h>
+#include <signal.h>
+#include <stdbool.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/syscall.h>
+#include <sys/types.h>
+#include <unistd.h>
+
+#include "utils.h"
+
+/**
+ * The process waits for the creation of a file passed as argument from an
+ * external processes to execute a syscall and exiting. This is useful for tests
+ * in combinaison with LTTng's PID tracker feature where we can trace the kernel
+ * events generated by our test process only.
+ */
+
+volatile int val = 0;
+
+long __attribute__ ((noinline))
+my_gettid(void)
+{
+    long ret;
+#ifdef __x86_64
+    asm volatile
+    (
+        "syscall"
+        : "=a" (ret)
+        : "0"(__NR_gettid)
+        : "cc", "rcx", "r11", "memory"
+    );
+#elif __i386
+    asm volatile
+    (
+        "int $0x80"
+        : "=a" (ret)
+        : "0"(__NR_gettid)
+        : "cc", "edi", "esi", "memory"
+    );
+#else
+#error "Userspace callstack test not supported for this architecture."
+#endif
+    return ret;
+}
+
+int __attribute__ ((noinline))
+fct_c(void)
+{
+       return my_gettid();
+}
+
+int __attribute__ ((noinline))
+fct_b(void)
+{
+       val += fct_c();
+       return val;
+}
+
+int __attribute__ ((noinline))
+fct_a(void)
+{
+       val += fct_b();
+       return val;
+}
+
+int main(int argc, char **argv)
+{
+       int ret = 0;
+       char *start_file;
+
+       if (argc != 2) {
+               fprintf(stderr, "Error: Missing argument\n");
+               fprintf(stderr, "USAGE: %s PATH_WAIT_FILE\n", argv[0]);
+               ret = -1;
+               goto error;
+       }
+
+       start_file = argv[1];
+
+       /*
+        * Wait for the start_file to be created by an external process
+        * (typically the test script) before executing the syscall
+        */
+       ret = wait_on_file(start_file);
+       if (ret != 0) {
+               goto error;
+       }
+
+       /* Start the callchain to the syscall */
+       ret = fct_a();
+
+       /* Return success */
+       if (ret >= 0) {
+               ret = 0;
+       }
+
+error:
+       return ret;
+}