Add -k option to print stack trace after each syscall
Print the stack trace of the traced process after each system call when
-k option is specified. It is implemented using libunwind to unwind the
stack and to obtain the function name pointed by the IP.
Based on the code that was originally taken from strace-plus
of Philip J. Guo.
* configure.ac: Add --with-libunwind option. Check libunwind support.
* Makefile.am: Add libunwind support.
* defs.h (struct tcb) [USE_LIBUNWIND]: Append libunwind specific fields.
[USE_LIBUNWIND] (stack_trace_enabled, alloc_mmap_cache,
delete_mmap_cache, print_stacktrace): New prototypes.
* mem.c (print_mmap, sys_munmap, sys_mprotect): Add libunwind support.
* process.c (sys_execve): Likewise.
* strace.c (usage, alloctcb, droptcb, init): Likewise.
* syscall.c (trace_syscall_exiting): Likewise.
* unwind.c: New file.
* strace.1: Document -k option.
diff --git a/defs.h b/defs.h
index 34a8874..825fc79 100644
--- a/defs.h
+++ b/defs.h
@@ -425,6 +425,12 @@
struct timeval etime; /* Syscall entry time */
/* Support for tracing forked processes: */
long inst[2]; /* Saved clone args (badly named) */
+
+#ifdef USE_LIBUNWIND
+ struct UPT_info* libunwind_ui;
+ struct mmap_cache_t* mmap_cache;
+ unsigned int mmap_cache_size;
+#endif
};
/* TCB flags */
@@ -559,6 +565,10 @@
extern bool need_fork_exec_workarounds;
extern unsigned xflag;
extern unsigned followfork;
+#ifdef USE_LIBUNWIND
+/* if this is true do the stack trace for every system call */
+extern bool stack_trace_enabled;
+#endif
extern unsigned ptrace_setoptions;
extern unsigned max_strlen;
extern unsigned os_release;
@@ -721,6 +731,15 @@
extern void tv_mul(struct timeval *, const struct timeval *, int);
extern void tv_div(struct timeval *, const struct timeval *, int);
+#ifdef USE_LIBUNWIND
+extern void init_unwind_addr_space(void);
+extern void init_libunwind_ui(struct tcb *tcp);
+extern void free_libunwind_ui(struct tcb *tcp);
+extern void alloc_mmap_cache(struct tcb* tcp);
+extern void delete_mmap_cache(struct tcb* tcp);
+extern void print_stacktrace(struct tcb* tcp);
+#endif
+
/* Strace log generation machinery.
*
* printing_tcp: tcb which has incomplete line being printed right now.