Fix automake to support bootstrapping the compiler.

c++/Makefile.am

@@ -42,7 +42,7 @@ EXTRA_DIST =                                                                 \
   LICENSE.txt                                                                \
   $(test_capnpc_inputs)
 
-CLEANFILES = $(test_capnpc_outputs) capnpc_middleman test_capnpc_middleman
+CLEANFILES = $(test_capnpc_outputs) test_capnpc_middleman
 
 # Deletes all the files generated by autoreconf.
 MAINTAINERCLEANFILES =   \
@@ -76,12 +76,6 @@ maintainer-clean-local:
 %.capnp:
 	@:
 
-# Implicit rules for invoking capnpc.
-%.capnp.h: %.capnp
-	$(CAPNPC) --src-prefix=$(srcdir) -oc++ -I$(srcdir)/src $^
-%.capnp.c++: %.capnp.h
-	@:
-
 public_capnpc_inputs =                                         \
   src/capnp/c++.capnp                                          \
   src/capnp/schema.capnp
@@ -200,7 +194,7 @@ nodist_libcapnp_la_SOURCES =                                   \
   src/capnp/schema.capnp.c++                                   \
   src/capnp/c++.capnp.c++
 
-bin_PROGRAMS = capnp capnpc-capnp
+bin_PROGRAMS = capnp capnpc-capnp capnpc-c++
 
 capnp_LDADD = $(PTHREAD_LIBS) libcapnp.la
 capnp_SOURCES = src/capnp/compiler/capnp.c++
@@ -208,6 +202,9 @@ capnp_SOURCES = src/capnp/compiler/capnp.c++
 capnpc_capnp_LDADD = $(PTHREAD_LIBS) libcapnp.la
 capnpc_capnp_SOURCES = src/capnp/compiler/capnpc-capnp.c++
 
+capnpc_c___LDADD = $(PTHREAD_LIBS) libcapnp.la
+capnpc_c___SOURCES = src/capnp/compiler/capnpc-c++.c++
+
 # Source files intentionally not included in the dist at this time:
 #  src/capnp/serialize-snappy*
 #  src/capnp/benchmark/...
@@ -225,6 +222,22 @@ test_capnpc_outputs =                                          \
   src/capnp/test-import.capnp.c++                              \
   src/capnp/test-import.capnp.h
 
+if USE_EXTERNAL_CAPNP
+
+test_capnpc_middleman: $(test_capnpc_inputs)
+	$(CAPNP) compile --src-prefix=$(srcdir)/src -o$(CAPNPC_CXX):src -I$(srcdir)/src $^
+	touch test_capnpc_middleman
+
+else
+
+test_capnpc_middleman: capnp$(EXEEXT) capnpc-c++$(EXEEXT) $(test_capnpc_inputs)
+	echo $^ | (read CAPNP CAPNPC_CXX SOURCES && ./$$CAPNP compile --src-prefix=$(srcdir)/src -o./$$CAPNPC_CXX:src -I$(srcdir)/src $$SOURCES)
+	touch test_capnpc_middleman
+
+endif
+
+$(test_capnpc_outputs): test_capnpc_middleman
+
 BUILT_SOURCES = $(test_capnpc_outputs)
 
 check_PROGRAMS = capnp-test

c++/configure.ac

@@ -14,11 +14,14 @@ AS_IF([test "x${ac_cv_env_CFLAGS_set}" = "x"],
 AS_IF([test "x${ac_cv_env_CXXFLAGS_set}" = "x"],
       [CXXFLAGS="-O2 -DNDEBUG"])
 
-AS_IF([test "x$CAPNPC" = "x"], [CAPNPC="capnpc"])
-AC_SUBST([CAPNPC])
-
 AM_INIT_AUTOMAKE
 
+AC_ARG_WITH([external-capnp],
+  [AS_HELP_STRING([--with-external-capnp],
+    [use the system capnp binary (or the one specified with $CAPNP) instead of compiling a new
+     one (useful for cross-compiling)])],
+  [external_capnp=yes],[external_capnp=no])
+
 # Checks for programs.
 AC_PROG_CC
 AC_PROG_CXX
@@ -27,6 +30,24 @@ AX_CXX_COMPILE_STDCXX_11([noext])
 ACX_PTHREAD
 AC_PROG_LIBTOOL
 
+AS_IF([test "$external_capnp" != "no"], [
+	AS_IF([test "x$CAPNP" = "x"], [CAPNP="capnp"], [with_capnp=yes])
+	AS_IF([test "x$CAPNPC_CXX" = "x"], [
+	  # CAPNPC_CXX was not specified.  Choose a reasonable default.
+	  AS_CASE([$CAPNP], [*/*], [
+	    # $CAPNP contains a slash, so it's not on $PATH.  Assume capnpc-c++ is not either, but is
+	    # in the same directory.
+	    CAPNPC_CXX=`dirname $CAPNP`/capnpc-c++
+	  ], [
+	    # $CAPNP is on $PATH, so tell it to find the plugin on $PATH as well.
+	    CAPNPC_CXX="c++"
+	  ])
+	])
+	AC_SUBST([CAPNP])
+	AC_SUBST([CAPNPC_CXX])
+])
+AM_CONDITIONAL([USE_EXTERNAL_CAPNP], [test "$external_capnp" != "no"])
+
 LIBS="$PTHREAD_LIBS $LIBS"
 CXXFLAGS="$CXXFLAGS $PTHREAD_CFLAGS"
 

c++/src/capnp/compiler/capnp.c++

@@ -40,6 +40,7 @@
 #include <capnp/serialize.h>
 #include <capnp/serialize-packed.h>
 #include <limits>
+#include <errno.h>
 
 #if HAVE_CONFIG_H
 #include "config.h"
@@ -191,6 +192,11 @@ public:
   }
 
   kj::MainBuilder::Validity addSource(kj::StringPtr file) {
+    // Strip redundant "./" prefixes to make src-prefix matching more lenient.
+    while (file.startsWith("./")) {
+      file = file.slice(2);
+    }
+
     if (!compilerConstructed) {
       compiler = compilerSpace.construct(annotationFlag);
       compilerConstructed = true;
@@ -247,6 +253,16 @@ public:
   }
 
   kj::MainBuilder::Validity addSourcePrefix(kj::StringPtr prefix) {
+    // Strip redundant "./" prefixes to make src-prefix matching more lenient.
+    while (prefix.startsWith("./")) {
+      prefix = prefix.slice(2);
+    }
+
+    if (prefix == "" || prefix == ".") {
+      // Irrelevant prefix.
+      return true;
+    }
+
     if (prefix.endsWith("/")) {
       sourcePrefixes.add(kj::heapString(prefix));
     } else {
@@ -309,17 +325,34 @@ public:
         KJ_SYSCALL(dup2(pipeFds[0], STDIN_FILENO));
         KJ_SYSCALL(close(pipeFds[0]));
 
+        kj::Array<char> pwd = kj::heapArray<char>(256);
+        while (getcwd(pwd.begin(), pwd.size()) == nullptr) {
+          KJ_REQUIRE(pwd.size() < 8192, "WTF your working directory path is more than 8k?");
+          pwd = kj::heapArray<char>(pwd.size() * 2);
+        }
+
         if (output.dir != nullptr) {
           KJ_SYSCALL(chdir(output.dir.cStr()), output.dir);
         }
 
         if (shouldSearchPath) {
-          KJ_SYSCALL(execlp(exeName.cStr(), exeName.cStr(), nullptr));
+          execlp(exeName.cStr(), exeName.cStr(), nullptr);
         } else {
-          KJ_SYSCALL(execl(exeName.cStr(), exeName.cStr(), nullptr));
+          if (!exeName.startsWith("/")) {
+            // The name is relative.  Prefix it with our original working directory path.
+            exeName = kj::str(pwd.begin(), "/", exeName);
+          }
+
+          execl(exeName.cStr(), exeName.cStr(), nullptr);
         }
 
-        KJ_FAIL_ASSERT("execlp() returned?");
+        int error = errno;
+        if (error == ENOENT) {
+          context.exitError(kj::str(output.name, ": no such plugin (executable should be '",
+                                    exeName, "')"));
+        } else {
+          KJ_FAIL_SYSCALL("exec()", error);
+        }
       }
 
       KJ_SYSCALL(close(pipeFds[0]));
@@ -330,9 +363,9 @@ public:
       int status;
       KJ_SYSCALL(waitpid(child, &status, 0));
       if (WIFSIGNALED(status)) {
-        context.error(kj::str(exeName, ": plugin failed: ", strsignal(WTERMSIG(status))));
+        context.error(kj::str(output.name, ": plugin failed: ", strsignal(WTERMSIG(status))));
       } else if (WIFEXITED(status) && WEXITSTATUS(status) != 0) {
-        context.error(kj::str(exeName, ": plugin failed: exit code ", WEXITSTATUS(status)));
+        context.error(kj::str(output.name, ": plugin failed: exit code ", WEXITSTATUS(status)));
       }
     }
 

super-test.sh

@@ -107,7 +107,6 @@ __EOF__
     fi
     rm -f capnproto-*.tar.gz samples/addressbook samples/addressbook.capnp.c++ \
           samples/addressbook.capnp.h
-    rm -rf gtest
     exit 0
   elif [ "x$1" == "xhelp" ]; then
     echo "usage: $0 [COMMAND]"
@@ -171,8 +170,11 @@ echo "========================================================================="
 
 doit make install
 
+"x$(which capnp)" == "x$STAGING/bin/capnp"
+"x$(which capnpc-c++)" == "x$STAGING/bin/capnpc-c++"
+
 cd samples
-doit capnpc -oc++ addressbook.capnp -I"$STAGING"/include
+doit capnp compile -oc++ addressbook.capnp -I"$STAGING"/include --no-standard-import
 doit ${CXX:-g++} -std=c++11 $SAMPLE_CXXFLAGS -I"$STAGING"/include -L"$STAGING"/lib \
     addressbook.c++ addressbook.capnp.c++ -lcapnp -pthread -o addressbook
 echo "@@@@ ./addressbook (in various configurations)"
@@ -181,6 +183,14 @@ echo "@@@@ ./addressbook (in various configurations)"
 rm addressbook addressbook.capnp.c++ addressbook.capnp.h
 cd ..
 
+echo "========================================================================="
+echo "Testing --with-external-capnp"
+echo "========================================================================="
+
+doit make distclean
+doit ./configure --prefix="$STAGING" --with-external-capnp CAPNP=$STAGING/bin/capnp
+doit make -j6 check
+
 doit make uninstall
 
 echo "========================================================================="