vere: mingw: get rid of libsigsegv

pkg/urbit/Makefile

@@ -77,9 +77,9 @@ build/urbit-worker: $(common_objs) $(worker_objs)
 	@mkdir -p ./build
 	@$(CC) $^ $(LDFLAGS) -o $@
 
-%.o: %.c $(headers)
+%.o: %.c $(headers) $(CCDEPS)
 	@echo CC $<
-	@$(CC) -I./include $(CFLAGS) -c $< -o $@
+	@$(CC) -I./include $(CFLAGS) $< $(CCEXTRA) -c -o $@
 
 tags: $(all_srcs) $(headers)
 	ctags $^

pkg/urbit/compat/mingw/compat.h

@@ -12,6 +12,7 @@ int kill(pid_t pid, int signum);
 #define SIGUSR1   10
 #define SIGALRM   14
 #define SIGVTALRM 26
+#define SIGSTK    31
 #define SIG_COUNT 32
 
 #endif//_MINGW_IO_H

pkg/urbit/compat/mingw/poor-mans-nix-shell.sh

@@ -1,5 +1,5 @@
 # ensure required mingw packages are installed
-mpkgs=(cmake curl gcc jq libsigsegv libuv make wslay)
+mpkgs=(cmake curl gcc jq libuv make wslay)
 pacman -S --needed autoconf automake-wrapper libtool patch ${mpkgs[@]/#/mingw-w64-x86_64-}
 
 declare -a cdirs

pkg/urbit/compat/mingw/seh_handler_decorator.cc

@@ -0,0 +1,65 @@
+#include <stdio.h>
+#include <string.h>
+
+enum { INIT, CPAR, DQ, DQS, SQ, SQS };
+char line[1 << 16];
+
+/* seh_handler_decorator: registers u3_exception_handler for all non-inline functions
+*/
+int main(int argc, const char* argv[])
+{
+    if (argc != 2)
+        return 1;
+
+    int c, state = INIT, curly = 0, emit = 0;
+
+    while (fgets(line, sizeof(line), stdin))
+    {
+        if (line[0] == '#')
+        {
+            emit = !!strstr(line, argv[1]);
+            fputs(line, stdout);
+        }
+        else
+        for (int i = 0; line[i]; i++)
+        {
+            switch (state) {
+            case INIT:
+            case CPAR:
+                switch (line[i]) {
+                case ' ':
+                case '\t':
+                case '\n':
+                case '\r':
+                case '\f': break;
+                case '{':  curly++; if (emit && curly == 1 && state == CPAR) goto emit_handler; goto reset;
+                case '}':  curly--; goto reset;
+                case '"':  state = DQ;   break;
+                case '\'': state = SQ;   break;
+                case ')':  state = CPAR; break;
+                reset:
+                default:   state = INIT; break;
+                } break;
+            case DQ:
+                switch (line[i]) {
+                case '\\': state = DQS;  break;
+                case '"':  state = INIT; break;
+                } break;
+            case DQS:      state = DQ;   break;
+            case SQ:
+                switch (line[i]) {
+                case '\\': state = SQS;  break;
+                case '\'': state = INIT; break;
+                } break;
+            case SQS:      state = SQ;   break;
+            }
+            fputc(line[i], stdout);
+            continue;
+        emit_handler:
+            fputs("{__asm__(\".seh_handler u3_exception_handler,@except\\n\");", stdout);
+            state = INIT;
+        }
+    }
+
+    return 0;
+}

pkg/urbit/compat/mingw/seh_handler_decorator.mk

@@ -0,0 +1,6 @@
+sehdexe := build/seh_handler_decorator.exe
+CCDEPS  := $(CCDEPS) $(sehdexe)
+CCEXTRA  = -E -o -|$(sehdexe) $<|$(CC) $(CFLAGS) -x cpp-output -
+
+$(sehdexe): compat/mingw/seh_handler_decorator.cc
+	@$(CC) $< -o $@

pkg/urbit/configure

@@ -111,6 +111,7 @@ case $(tr A-Z a-z <<< $os) in
        CFLAGS="${CFLAGS-} -O3 -g"
      fi
 
+     deps="${deps/sigsegv}"
      compat="${compat-} mingw"
      CFLAGS="${CFLAGS-} ${cdirs[@]}"
      LDFLAGS="${LDFLAGS-} ${ldirs[@]} -static"

pkg/urbit/daemon/main.c

@@ -5,7 +5,9 @@
 #define C3_GLOBAL
 #include "all.h"
 #include "vere/vere.h"
+#if !defined(U3_OS_mingw)
 #include <sigsegv.h>
+#endif
 #include <openssl/conf.h>
 #include <openssl/engine.h>
 #include <openssl/err.h>
@@ -512,9 +514,11 @@ report(void)
 {
   printf("urbit %s\n", URBIT_VERSION);
   printf("gmp: %s\n", gmp_version);
+#if !defined(U3_OS_mingw)
   printf("sigsegv: %d.%d\n",
          (libsigsegv_version >> 8) & 0xff,
          libsigsegv_version & 0xff);
+#endif
   printf("openssl: %s\n", SSLeay_version(SSLEAY_VERSION));
   printf("libuv: %s\n", uv_version_string());
   printf("libh2o: %d.%d.%d\n",

pkg/urbit/noun/manage.c

@@ -8,7 +8,6 @@
 #include <fcntl.h>
 #include <sys/stat.h>
 #include <ctype.h>
-#include <sigsegv.h>
 #include <openssl/crypto.h>
 
 //  XX stack-overflow recovery should be gated by -a
@@ -83,12 +82,38 @@
 //
 static rsignal_jmpbuf u3_Signal;
 
+#if defined(U3_OS_mingw)
+/* u3_exception_handler: replaces libsigsegv on MingW
+*/
+EXCEPTION_DISPOSITION u3_exception_handler(
+    IN PEXCEPTION_RECORD ExceptionRecord,
+    IN ULONG64 EstablisherFrame,
+    IN OUT PCONTEXT ContextRecord,
+    IN OUT PDISPATCHER_CONTEXT DispatcherContext)
+{
+    if (ExceptionRecord->ExceptionCode == EXCEPTION_ACCESS_VIOLATION &&
+        ExceptionRecord->ExceptionInformation[0] == 1 &&
+        u3e_fault((void*)ExceptionRecord->ExceptionInformation[1], 1))
+    {
+        return ExceptionContinueExecution;
+    }
+
+    if (ExceptionRecord->ExceptionCode == EXCEPTION_STACK_OVERFLOW) {
+        rsignal_raise(SIGSTK);
+    }
+
+    return ExceptionContinueSearch;
+}
+#else
+#include <sigsegv.h>
+
 #ifndef SIGSTKSZ
 # define SIGSTKSZ 16384
 #endif
 #ifndef NO_OVERFLOW
 static uint8_t Sigstk[SIGSTKSZ];
 #endif
+#endif
 
 #if 0
 /* _cm_punt(): crudely print trace.
@@ -135,17 +160,25 @@ static void _cm_overflow(void *arg1, void *arg2, void *arg3)
 static void
 _cm_signal_handle(c3_l sig_l)
 {
+#ifndef U3_OS_mingw
   if ( c3__over == sig_l ) {
+#ifndef NO_OVERFLOW
     sigsegv_leave_handler(_cm_overflow, NULL, NULL, NULL);
-  }
-  else {
+#endif
+  } else
+#endif
+  {
     u3m_signal(sig_l);
   }
 }
 
 #ifndef NO_OVERFLOW
 static void
+#ifndef U3_OS_mingw
 _cm_signal_handle_over(int emergency, stackoverflow_context_t scp)
+#else
+_cm_signal_handle_over(int x)
+#endif
 {
   _cm_signal_handle(c3__over);
 }
@@ -336,7 +369,11 @@ _cm_signal_deep(c3_w mil_w)
   }
 
 #ifndef NO_OVERFLOW
+#ifndef U3_OS_mingw
   stackoverflow_install_handler(_cm_signal_handle_over, Sigstk, SIGSTKSZ);
+#else
+  rsignal_install_handler(SIGSTK, _cm_signal_handle_over);
+#endif
 #endif
   rsignal_install_handler(SIGINT, _cm_signal_handle_intr);
   rsignal_install_handler(SIGTERM, _cm_signal_handle_term);
@@ -376,7 +413,11 @@ _cm_signal_done()
   rsignal_deinstall_handler(SIGVTALRM);
 
 #ifndef NO_OVERFLOW
+#ifndef U3_OS_mingw
   stackoverflow_deinstall_handler();
+#else
+  rsignal_deinstall_handler(SIGSTK);
+#endif
 #endif
   {
     struct itimerval itm_u;
@@ -1624,10 +1665,12 @@ _cm_limits(void)
 static void
 _cm_signals(void)
 {
+# if !defined(U3_OS_mingw)
   if ( 0 != sigsegv_install_handler(u3e_fault) ) {
     u3l_log("boot: sigsegv install failed\n");
     exit(1);
   }
+# endif
 
 # if defined(U3_OS_PROF)
   //  Block SIGPROF, so that if/when we reactivate it on the