[kvm-unit-tests v2 8/8] scripts: pretty print stack traces

[Peter Feiner <pfeiner@google.com>]

Optionally pretty print stacks in test.log with 'run_tests.sh -p'.

The script runs addresses through addr2line to get file names and line
numbers.  Also prints out source code lines if files are available.
For example

0x004013f5: ac_test_exec at x86/access.c:818
            }
      >     ac_test_setup_pte(at, pool);
            r = ac_test_do_access(at);
0x004014dd: ac_test_run at x86/access.c:852
                ++tests;
      >         successes += ac_test_exec(&at, &pool);
            } while (ac_test_bump(&at));
0x0040157d: main at x86/access.c:873
            printf("starting test\n\n");
      >     r = ac_test_run();
            return r ? 0 : 1;
0x0040028e: start64 at x86/cstart64.S:206
                lea __argv(%rip), %rsi
      >         call main
                mov %eax, %edi

Signed-off-by: Peter Feiner <pfeiner@google.com>
---
 run_tests.sh                   | 10 +++++--
 scripts/pretty_print_stacks.py | 61 ++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 69 insertions(+), 2 deletions(-)
 create mode 100755 scripts/pretty_print_stacks.py

diff --git a/run_tests.sh b/run_tests.sh
index 2c8af36..13bc089 100755
--- a/run_tests.sh
+++ b/run_tests.sh
@@ -1,6 +1,7 @@
 #!/bin/bash
 
 verbose="no"
+pretty="no"
 
 if [ ! -f config.mak ]; then
     echo "run ./configure && make first. See ./configure -h"
@@ -18,6 +19,7 @@ Usage: $0 [-g group] [-h] [-v]
     -g: Only execute tests in the given group
     -h: Output this help text
     -v: Enables verbose mode
+    -p: Pretty print stack traces in test.log
 
 Set the environment variable QEMU=/path/to/qemu-system-ARCH to
 specify the appropriate qemu binary for ARCH-run.
@@ -27,8 +29,9 @@ EOF
 
 RUNTIME_arch_run="./$TEST_DIR/run"
 source scripts/runtime.bash
+log_redir=">> test.log"
 
-while getopts "g:hv" opt; do
+while getopts "g:hvp" opt; do
     case $opt in
         g)
             only_group=$OPTARG
@@ -40,13 +43,16 @@ while getopts "g:hv" opt; do
         v)
             verbose="yes"
             ;;
+        p)
+           log_redir="> >(./scripts/pretty_print_stacks.py \$kernel >> test.log)"
+           ;;
         *)
             exit
             ;;
     esac
 done
 
-RUNTIME_arch_run="./$TEST_DIR/run >> test.log"
+RUNTIME_arch_run="./$TEST_DIR/run $log_redir"
 config=$TEST_DIR/unittests.cfg
 rm -f test.log
 echo > test.log
diff --git a/scripts/pretty_print_stacks.py b/scripts/pretty_print_stacks.py
new file mode 100755
index 0000000..49564bd
--- /dev/null
+++ b/scripts/pretty_print_stacks.py
@@ -0,0 +1,61 @@
+#!/usr/bin/env python
+
+import re
+import subprocess
+import sys
+
+if len(sys.argv) != 2:
+    sys.stderr.write('usage: %s <kernel>\n' % sys.argv[0])
+    sys.exit(1)
+
+binary = sys.argv[1]
+
+# Subvert output buffering.
+def puts(string):
+    sys.stdout.write(string)
+    sys.stdout.flush()
+
+try:
+    while True:
+        # Subvert input buffering.
+        line = sys.stdin.readline()
+        if line == '':
+            break
+
+        if not line.strip().startswith('STACK:'):
+            puts(line)
+            continue
+
+        addrs = line.split()[1:]
+        # Output like this:
+        #        0x004002be: start64 at path/to/kvm-unit-tests/x86/cstart64.S:208
+        #         (inlined by) test_ept_violation at path/to/kvm-unit-tests/x86/vmx_tests.c:1719 (discriminator 1)
+        cmd = ['addr2line', '-e', binary, '-i', '-f', '--pretty', '--address']
+        cmd.extend(addrs)
+
+        p = subprocess.Popen(cmd, stdout=subprocess.PIPE)
+        out, err = p.communicate()
+        if p.returncode != 0:
+            puts(line)
+            continue
+
+        for line in out.splitlines():
+            m = re.match('(.*) at [^ ]*/kvm-unit-tests/([^ ]*):([0-9]+)(.*)', line)
+            if m is None:
+                puts('%s\n' % line)
+                continue
+
+            head, path, line, tail = m.groups()
+            line = int(line)
+            puts('%s at %s:%d%s\n' % (head, path, line, tail))
+            try:
+                lines = open(path).readlines()
+            except IOError:
+                continue
+            if line > 1:
+                puts('        %s\n' % lines[line - 2].rstrip())
+            puts('      > %s\n' % lines[line - 1].rstrip())
+            if line < len(lines):
+                puts('        %s\n' % lines[line].rstrip())
+except:
+    sys.exit(1)
-- 
2.7.0.rc3.207.g0ac5344