menu_displaylist: extend the validation dump to menu_displaylist_ctl

The dump's first pass covers menu_displaylist_build_list; the
271-case ctl switch it hangs off had no coverage at all. A second
pass now drives ctl for every dumpable type, each in a forked child
built from identical pristine parent state, streaming its rows,
return value and final flags back through a pipe - a crashing case
names its signal in the dump and the run continues, and no case
sees another's side effects. On this build that is 189 clean
sections and 2,034 rows of new deterministic coverage, with sixteen
headless-crash cases recorded rather than hidden. POSIX only,
compiled solely under the validation flag; release builds carry
nothing.

Author: libretroadmin

menu/menu_displaylist.c

@@ -7143,6 +7143,10 @@ static unsigned menu_displaylist_netplay_refresh_rooms(file_list_t *list)
 }
 #endif
 
+#if defined(RETROARCH_VALIDATION_DUMPS) && !defined(_WIN32)
+#include <unistd.h>
+#include <sys/wait.h>
+#endif
 #if defined(RETROARCH_VALIDATION_DUMPS)
 /* Validation dump for the displaylist build path.
  *
@@ -7213,6 +7217,81 @@ void menu_displaylist_validation_dump(rarch_setting_t *list_settings)
                list.list[i].type, (unsigned)list.list[i].entry_idx);
       file_list_deinitialize(&list);
    }
+   /* Second pass: menu_displaylist_ctl itself, the 271-case switch
+    * the first pass never reached.  Each type builds in a forked
+    * child from identical pristine parent state, so one crashing or
+    * hanging case names itself in the dump without taking the run
+    * down, and no case sees another's side effects.  POSIX only;
+    * the dump is a validation tool and never ships. */
+#if !defined(_WIN32)
+   for (t = 0; t <= (unsigned)DISPLAYLIST_PENDING_CLEAR; t++)
+   {
+      int pfd[2];
+      pid_t pid;
+      if (t == (unsigned)DISPLAYLIST_INFORMATION_LIST
+            || t == (unsigned)DISPLAYLIST_SYSTEM_INFO
+            || t == (unsigned)DISPLAYLIST_HELP_SCREEN_LIST
+            || (t >= (unsigned)DISPLAYLIST_CORE_CONTENT
+                  && t <= (unsigned)DISPLAYLIST_CORE_SYSTEM_FILES))
+      {
+         filestream_printf(f, "=c= %u skipped\n", t);
+         continue;
+      }
+      filestream_printf(f, "=c= %u ", t);
+      filestream_flush(f);
+      if (pipe(pfd) != 0)
+         break;
+      if ((pid = fork()) == 0)
+      {
+         file_list_t cl;
+         menu_displaylist_info_t info;
+         FILE *w = fdopen(pfd[1], "w");
+         size_t i2;
+         bool ret;
+         close(pfd[0]);
+         memset(&cl, 0, sizeof(cl));
+         menu_displaylist_info_init(&info);
+         info.list = &cl;
+         ret = menu_displaylist_ctl(
+               (enum menu_displaylist_ctl_state)t, &info, settings);
+         if (w)
+         {
+            fprintf(w, "ret=%d flags=%08x size=%u\n",
+                  ret ? 1 : 0, (unsigned)info.flags, (unsigned)cl.size);
+            for (i2 = 0; i2 < cl.size; i2++)
+               fprintf(w, "%u|%s|%s|%u|%u\n", (unsigned)i2,
+                     cl.list[i2].path  ? cl.list[i2].path  : "",
+                     cl.list[i2].label ? cl.list[i2].label : "",
+                     cl.list[i2].type, (unsigned)cl.list[i2].entry_idx);
+            fflush(w);
+         }
+         _exit(0);
+      }
+      else if (pid > 0)
+      {
+         char buf[512];
+         ssize_t r;
+         int status = 0;
+         close(pfd[1]);
+         while ((r = read(pfd[0], buf, sizeof(buf))) > 0)
+            filestream_write(f, buf, (size_t)r);
+         close(pfd[0]);
+         waitpid(pid, &status, 0);
+         if (WIFSIGNALED(status))
+            filestream_printf(f, "crashed sig=%d\n", WTERMSIG(status));
+         else if (!WIFEXITED(status) || WEXITSTATUS(status) != 0)
+            filestream_printf(f, "exit=%d\n",
+                  WIFEXITED(status) ? WEXITSTATUS(status) : -1);
+         filestream_flush(f);
+      }
+      else
+      {
+         close(pfd[0]);
+         close(pfd[1]);
+         break;
+      }
+   }
+#endif
    menu_st->entries.list_settings = saved_list;
    filestream_close(f);
 }