Output the current call stack programmatically.

Adds a function that will show some information about the current call stack. Useful to see where the code you are interested in is being called from without opening up a debugger Not as good as line numbers are not available.

Sample output:

[0000] [00000.9] print_backtrace: threadpool_map
[0000] [00000.9] print_backtrace: eagle_6.yml(print_backtrace+0x67) [0x557d7e749ae7]
[0000] [00000.9] print_backtrace: eagle_6.yml(threadpool_map+0x136) [0x557d7e6b51a6]
[0000] [00000.9] print_backtrace: eagle_6.yml(space_free_cells+0x48) [0x557d7e625a68]
[0000] [00000.9] print_backtrace: eagle_6.yml(space_regrid+0x1396) [0x557d7e614ac6]
[0000] [00000.9] print_backtrace: eagle_6.yml(space_rebuild+0x5a) [0x557d7e60f00a]
[0000] [00000.9] print_backtrace: eagle_6.yml(engine_rebuild+0x8f) [0x557d7e63578f]
[0000] [00000.9] print_backtrace: eagle_6.yml(engine_init_particles+0x97) [0x557d7e639527]
[0000] [00000.9] print_backtrace: eagle_6.yml(main+0x4245) [0x557d7e5ff1c5]

[0000] [00000.8] print_backtrace: eagle_6.yml(print_backtrace+0x67) [0x557d7e749ae7]
[0000] [00000.8] print_backtrace: eagle_6.yml(threadpool_map+0x136) [0x557d7e6b51a6]
[0000] [00000.8] print_backtrace: eagle_6.yml(engine_redistribute+0xfb0) [0x557d7e65e250]
[0000] [00000.8] print_backtrace: eagle_6.yml(engine_split+0x78) [0x557d7e637588]
[0000] [00000.8] print_backtrace: eagle_6.yml(main+0x4231) [0x557d7e5ff1b1]
[0000] [00000.8] print_backtrace: /lib/x86_64-linux-gnu/libc.so.6(+0x29d90) [0x14a6a6644d90]
[0000] [00000.8] print_backtrace: /lib/x86_64-linux-gnu/libc.so.6(__libc_start_main+0x80) [0x14a6a6644e40]

So not sure why the program is shown as the parameter file, but the basics are clear.

Uses glibc call so also configured as needed.

src/debug.c

@@ -30,6 +30,10 @@
 #include <stdio.h>
 #include <unistd.h>
 
+#ifdef HAVE_BACKTRACE
+#include <execinfo.h>
+#endif
+
 /* Local includes. */
 #include "active.h"
 #include "black_holes_debug.h"
@@ -819,3 +823,27 @@ void dumpCellRanks(const char *prefix, struct cell *cells_top, int nr_cells) {
 }
 
 #endif /* HAVE_MPI */
+
+/**
+ * @brief Output a backtrace of the current calling stack.
+ *
+ * Requires the glibc extension backtrace().
+ *
+ * @param description some string to output along with the stack.
+ */
+void print_backtrace(const char *description) {
+#ifdef HAVE_BACKTRACE
+
+  message("%s", description);
+
+  /* Boiler plate from the man page. */
+  void *buffer[100];
+  int nptrs = backtrace(buffer, 100);
+  char **strings = backtrace_symbols(buffer, nptrs);
+  if (strings == NULL) {
+    perror("backtrace_symbols");
+  } else {
+    for (int j = 0; j < nptrs; j++) message("%s", strings[j]);
+  }
+#endif
+}