From 455c47f1f18858c439ff0a0b833ce93c9f79045f Mon Sep 17 00:00:00 2001

From: Martin Milata <mmilata@redhat.com>

Date: Mon, 24 Nov 2014 14:38:06 +0100

Subject: [PATCH 4/5] debug unwinding from core hook using satyr binary

Write "|/usr/bin/satyr debug unwind-from-hook %e %i %s" to

/proc/sys/kernel/core_pattern in order to use this. Before kernel 3.18

the %i flag is not available - you can use %p for single-thread

processes.

Related to abrt/abrt#829.

Signed-off-by: Martin Milata <mmilata@redhat.com>

---

 satyr.c | 81 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

 1 file changed, 81 insertions(+)

diff --git a/satyr.c b/satyr.c

index 7bdaa45..6e1ed28 100644

--- a/satyr.c

+++ b/satyr.c

@@ -20,6 +20,8 @@

 #include "gdb/stacktrace.h"

 #include "gdb/thread.h"

 #include "gdb/frame.h"

+#include "core/unwind.h"

+#include "core/stacktrace.h"

 #include "utils.h"

 #include "location.h"

 #include "strbuf.h"

@@ -37,6 +39,7 @@

 #include <sysexits.h>

 #include <assert.h>

 #include <libgen.h>

+#include <time.h>

 static char *g_program_name;

@@ -275,6 +278,82 @@ debug_duphash(int argc, char **argv)

 }

 static void

+debug_unwind_from_hook(int argc, char **argv)

+{

+    if (argc != 3)

+    {

+        fprintf(stderr, "Wrong number of arguments.\n");

+        fprintf(stderr, "Usage: satyr debug unwind-from-hook "

+                        "<executable> <tid> <signal>\n");

+        exit(1);

+    }

+

+    char *executable = argv[0];

+    char *end;

+    unsigned long tid = strtoul(argv[1], &end, 10);

+    if (*end != '\0')

+    {

+        fprintf(stderr, "Wrong tid\n");

+        exit(1);

+    }

+

+    unsigned long signum = strtoul(argv[2], &end, 10);

+    if (*end != '\0')

+    {

+        fprintf(stderr, "Wrong signal number\n");

+        exit(1);

+    }

+

+    char *error_message = NULL;

+    struct sr_core_stacktrace *core_stacktrace;

+

+    core_stacktrace = sr_core_stacktrace_from_core_hook(tid, executable, signum,

+                                                        &error_message);

+    if (!core_stacktrace)

+    {

+        fprintf(stderr, "Unwind failed: %s\n", error_message);

+        exit(1);

+    }

+

+    char *json = sr_core_stacktrace_to_json(core_stacktrace);

+    // Add newline to the end of core stacktrace file to make text

+    // editors happy.

+    json = sr_realloc(json, strlen(json) + 2);

+    strcat(json, "\n");

+

+    time_t t = time(NULL);

+    struct tm *tm = localtime(&t);

+    char core_backtrace_filename[256];

+

+    if (tm == NULL)

+    {

+        perror("localtime");

+        exit(1);

+    }

+

+    if (strftime(core_backtrace_filename, sizeof(core_backtrace_filename),

+                 "/tmp/satyr-core-stacktrace-%F-%T.json", tm) == 0)

+    {

+        fprintf(stderr, "stftime failed\n");

+        exit(1);

+    }

+

+

+    bool success = sr_string_to_file(core_backtrace_filename,

+                                    json,

+                                    &error_message);

+

+    if (!success)

+    {

+        fprintf(stderr, "Failed to write stacktrace: %s\n", error_message);

+        exit(1);

+    }

+

+    free(json);

+    sr_core_stacktrace_free(core_stacktrace);

+}

+

+static void

 debug(int argc, char **argv)

 {

     /* Debug command requires a subcommand. */

@@ -288,6 +367,8 @@ debug(int argc, char **argv)

         debug_normalize(argc - 1, argv + 1);

     else if (0 == strcmp(argv[0], "duphash"))

         debug_duphash(argc - 1, argv + 1);

+    else if (0 == strcmp(argv[0], "unwind-from-hook"))

+        debug_unwind_from_hook(argc - 1, argv + 1);

     else

     {

         fprintf(stderr, "Unknown debug subcommand.\n");

-- 

2.4.3