Threading support.

Since Windows doesn't support pthreads without an external library, I used a
mess of #defines.

Also, some of the #defines are not needed; I copied them from an earlier
project.  Detached threads and cond variables are not used at the moment, if
you feel bad about dormant code we can axe them.

1 files changed, 21 insertions, 1 deletions

diff --git a/crawl-ref/source/crash.cc b/crawl-ref/source/crash.cc
index b9823ae27f..9fddfeffbe 100644
--- a/crawl-ref/source/crash.cc
+++ b/crawl-ref/source/crash.cc
@@ -62,10 +62,11 @@ template <typename TO, typename FROM> TO nasty_cast(FROM f)
 
 #include "externs.h"
 #include "files.h"
+#include "initfile.h"
 #include "options.h"
 #include "state.h"
 #include "stuff.h"
-#include "initfile.h"
+#include "threads.h"
 
 /////////////////////////////////////////////////////////////////////////////
 // Code for printing out debugging info on a crash.
@@ -73,9 +74,18 @@ template <typename TO, typename FROM> TO nasty_cast(FROM f)
 #ifdef USE_UNIX_SIGNALS
 static int _crash_signal    = 0;
 static int _recursion_depth = 0;
+static mutex_t crash_mutex;
 
 static void _crash_signal_handler(int sig_num)
 {
+    // We rely on mutexes ignoring locks held by the same process, on some
+    // platforms this must be explicitely enabled (and we do so).
+
+    // This mutex is never unlocked again -- the first thread to crash will
+    // do a dump then terminate the process while everyone else waits here
+    // forever.
+    mutex_lock(crash_mutex);
+
     if (crawl_state.game_crashed)
     {
         if (_recursion_depth > 0)
@@ -143,6 +153,8 @@ static void _crash_signal_handler(int sig_num)
 
 void init_crash_handler()
 {
+    mutex_init(crash_mutex);
+
 #if defined(USE_UNIX_SIGNALS)
 
     for (int i = 1; i <= 64; i++)
@@ -316,3 +328,11 @@ void write_stack_trace(FILE* file, int ignore_count)
     fprintf(file, "%s", msg);
 }
 #endif
+
+void disable_other_crashes()
+{
+    // If one thread calls end() without going through a crash (a handled
+    // fatal error), no one else should be allowed to crash.  We're already
+    // going down so blocking the other thread is ok.
+    mutex_lock(crash_mutex);
+}