Re: [Crash-utility] [PATCH] crash: add python wrapper script

Add simple script with caching (just one startup can take quite some time and it saved hours during debugging). Script expects 2 symlinks ("crash vmlinux core") and is designed for post-mortem analysis. Script contains one example: fetching all inodes. Basically it is an example on how to run "crash" from Python. --- diff --git a/contrib/crash.py b/contrib/crash.py new file mode 100755 index 0000000..8dae0e1 --- /dev/null +++ b/contrib/crash.py @@ -0,0 +1,88 @@ +#!/usr/bin/python2 +import hashlib +import os +import subprocess +import tempfile + +# create "vmlinux" and "core" symlinks before running +#CRASH='/usr/bin/crash' +CRASH=os.path.join(os.path.expanduser('~'), 'bin', 'crash') + +# split() without empty strings +def xsplit(s, c): + i = 0 + while True: + j = s.find(c, i) + if j == -1: + if i == len(s): + return + yield s[i:] + return + elif i == j: + i = i + 1 + continue + else: + yield s[i:j] + i = j + 1 + +_CRASH_CACHE_DIR='.crash' +def crash(cmd): + idx = cmd.find('\n') + if idx >= 0: + print 'CRASH "%s" ...' % cmd[:idx] + else: + print 'CRASH "%s"' % cmd + + try: + os.mkdir(_CRASH_CACHE_DIR) + except OSError: + pass + + cache_filename = os.path.join(_CRASH_CACHE_DIR, hashlib.sha1(cmd).hexdigest()) + if os.path.isfile(cache_filename): + with open(cache_filename, 'r') as f: + return f.read() + + fd, filename = tempfile.mkstemp() + f = os.fdopen(fd, 'w') + f.write(cmd) + if cmd[-1] != '\n': + f.write('\n') + f.write('q\n') + f.close() + + with open(filename, 'r') as f: + x = subprocess.check_output([CRASH, '-s', 'vmlinux', 'core'], stdin=f) + os.unlink(filename) + + with open(cache_filename, 'w+') as f: + f.write(x) + return x + +def make_cmd(fmt, it): + return '\n'.join(map(lambda x: fmt % x, it)) + +#def struct_inode(): +# cmd = 'list -H super_blocks super_block.s_list' +# x = crash(cmd) +# list_sb = map(lambda x: int(x, 16), xsplit(x, '\n')) +# +# cmd = 'struct super_block.s_inodes' +# x = crash(cmd) +# s = [line for line in xsplit(x, '\n')] +# OFFSETOF_STRUCT_INODE_S_INODES = int(s[1].split()[0][1:-1]) +# +## set_inode = set() +## for sb in list_sb: +## cmd = 'list -H %x inode.i_sb_list' % (sb + OFFSETOF_STRUCT_INODE_S_INODES) +## x = crash(cmd) +## set_inode.update(map(lambda x: int(x, 16), xsplit(x, '\n'))) +## print len(set_inode) +# +# set_inode = set() +# cmd = make_cmd('list -H %x inode.i_sb_list', map(lambda x: x + OFFSETOF_STRUCT_INODE_S_INODES, list_sb)) +# x = crash(cmd) +# set_inode = set(map(lambda x: int(x, 16), xsplit(x, '\n'))) +# print len(set_inode) +# +#struct_inode()