AP_HAL_SITL: generate a core file for a given PID

Similarly to dumpstack.sh, uses gdb to dump a core file

libraries/AP_HAL_SITL/SITL_cmdline.cpp

@@ -53,6 +53,7 @@ static void _sig_fpe(int signum)
 {
     fprintf(stderr, "ERROR: Floating point exception - aborting\n");
     AP_HAL::dump_stack_trace();
+    AP_HAL::dump_core_file();
     abort();
 }
 
@@ -61,6 +62,7 @@ static void _sig_segv(int signum)
 {
     fprintf(stderr, "ERROR: segmentation fault - aborting\n");
     AP_HAL::dump_stack_trace();
+    AP_HAL::dump_core_file();
     abort();
 }
 

libraries/AP_HAL_SITL/system.cpp

@@ -37,6 +37,7 @@ void panic(const char *errormsg, ...)
     printf("\n");
 
     dump_stack_trace();
+    dump_core_file();
 
     if (getenv("SITL_PANIC_EXIT")) {
         // this is used on the autotest server to prevent us waiting
@@ -47,52 +48,54 @@ void panic(const char *errormsg, ...)
 }
 
 // partly flogged from: https://github.com/tridge/junkcode/blob/master/segv_handler/segv_handler.c
-void dump_stack_trace()
+void run_command_on_ownpid(const char *commandname)
 {
     // find dumpstack command:
-    const char *dumpstack = "dumpstack.sh"; // if we can't find it trust in PATH
+    const char *command_filepath = commandname; // if we can't find it trust in PATH
     struct stat statbuf;
     const char *paths[] {
-        "Tools/scripts/dumpstack.sh",
-        "APM/Tools/scripts/dumpstack.sh", // for autotest server
-        "../Tools/scripts/dumpstack.sh", // when run from e.g. ArduCopter subdirectory
+        "Tools/scripts/%s",
+        "APM/Tools/scripts/%s", // for autotest server
+        "../Tools/scripts/%s", // when run from e.g. ArduCopter subdirectory
     };
+    char buffer[60];
     for (uint8_t i=0; i<ARRAY_SIZE(paths); i++) {
-        if (::stat(paths[i], &statbuf) != -1) {
-            dumpstack = paths[i];
+        // form up a filepath from each path and commandname; if it
+        // exists, use it
+        snprintf(buffer, sizeof(buffer), paths[i], commandname);
+        if (::stat(buffer, &statbuf) != -1) {
+            command_filepath = buffer;
             break;
         }
     }
 
-    char cmd[100];
 	char progname[100];
-	char *p;
-	int n;
-
-	n = readlink("/proc/self/exe", progname, sizeof(progname)-1);
+	int n = readlink("/proc/self/exe", progname, sizeof(progname)-1);
 	if (n == -1) {
         strncpy(progname, "unknown", sizeof(progname));
         n = strlen(progname);
 	}
 	progname[n] = 0;
 
-	p = strrchr(progname, '/');
+	char *p = strrchr(progname, '/');
     if (p != nullptr) {
 	    *p = 0;
     } else {
         p = progname;
     }
 
-    char output_filepath[30];
+    char output_filepath[80];
     snprintf(output_filepath,
              ARRAY_SIZE(output_filepath),
-             "dumpstack_%s.%d.out",
+             "%s_%s.%d.out",
+             commandname,
              p+1,
              (int)getpid());
+    char cmd[200];
 	snprintf(cmd,
              sizeof(cmd),
              "sh %s %d >%s 2>&1",
-             dumpstack,
+             command_filepath,
              (int)getpid(),
              output_filepath);
     fprintf(stderr, "Running: %s\n", cmd);
@@ -101,8 +104,8 @@ void dump_stack_trace()
         fprintf(stderr, "Failed\n");
         return;
     }
-    fprintf(stderr, "Stack dumped\n");
-
+    fprintf(stderr, "%s has been run.  Output was:\n", commandname);
+    fprintf(stderr, "-------------- begin %s output ----------------\n", commandname);
     // print the trace on stderr:
     int fd = open(output_filepath, O_RDONLY);
     if (fd == -1) {
@@ -124,8 +127,17 @@ void dump_stack_trace()
             break;
         }
     }
+    fprintf(stderr, "-------------- end %s output ----------------\n", commandname);
     close(fd);
 }
+void dump_stack_trace()
+{
+    run_command_on_ownpid("dumpstack.sh");
+}
+void dump_core_file()
+{
+    run_command_on_ownpid("dumpcore.sh");
+}
 
 uint32_t micros()
 {