[PATCH 2/5] Improve portability (particularly for Woe32)

[Georgiy Tugai]

Test for siglongjmp, fcntl, GC_remove_roots; fallback to no-op.

2021-03-25  Georgiy Tugai  <georgiy@crossings.link>

        * bootstrap.conf: Add Gnulib modules arpa_inet, getsockname,
        listen, netdb, netinet_in, regex, sigaction, signal-h, sys_select,
        stpcpy
        * configure.ac: Add checks for siglongjmp, GC_remove_roots and a
        warning message for the latter
        * libpoke/pvm-alloc.c: Skip GC_remove_roots calls if not available
        * poke/pk-hserver.c: Include <sys/select.h>
        * poke/pk-mi.c: Include <sys/select.h>
        Skip fcntl calls if not available
        * poke/pk-repl.c: Skip siglongjmp/sigsetjmp calls and sigjmp_buf
        declaration if they are not available
---
 ChangeLog           | 14 ++++++++++++++
 bootstrap.conf      | 10 ++++++++++
 configure.ac        | 13 +++++++++++++
 libpoke/pvm-alloc.c |  2 ++
 poke/pk-hserver.c   |  1 +
 poke/pk-mi.c        |  7 +++++++
 poke/pk-repl.c      |  6 ++++++
 7 files changed, 53 insertions(+)

diff --git a/ChangeLog b/ChangeLog
index 626b8d0a..604ca010 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,17 @@
+2021-03-25  Georgiy Tugai  <georgiy@crossings.link>
+
+       * bootstrap.conf: Add Gnulib modules arpa_inet, getsockname,
+       listen, netdb, netinet_in, regex, sigaction, signal-h, sys_select,
+       stpcpy
+       * configure.ac: Add checks for siglongjmp, GC_remove_roots and a
+       warning message for the latter
+       * libpoke/pvm-alloc.c: Skip GC_remove_roots calls if not available
+       * poke/pk-hserver.c: Include <sys/select.h>
+       * poke/pk-mi.c: Include <sys/select.h>
+       Skip fcntl calls if not available
+       * poke/pk-repl.c: Skip siglongjmp/sigsetjmp calls and sigjmp_buf
+       declaration if they are not available
+
 2021-03-25  Georgiy Tugai  <georgiy@crossings.link>

        * etc/poke.g4: Rename CHAR to CHARACTER
diff --git a/bootstrap.conf b/bootstrap.conf
index 3d217f46..43d24631 100644
--- a/bootstrap.conf
+++ b/bootstrap.conf
@@ -21,6 +21,7 @@
 # gnulib modules used for this project.
 gnulib_modules="
   accept
+  arpa_inet
   array-list
   basename-lgpl
   bind
@@ -31,23 +32,31 @@ gnulib_modules="
   gethostname
   getline
   getopt-gnu
+  getsockname
   glob
   host-cpu-c-abi
   isatty
   libtextstyle-optional
+  listen
   maintainer-makefile
   mkstemp
+  netdb
+  netinet_in
   parse-datetime
   pmccabe2html
   printf-posix
   progname
   pthread
   readline
+  regex
+  sigaction
+  signal-h
   socket
   stdarg
   stdbool
   strchrnul
   streq
+  sys_select
   tmpdir
   unlink
   update-copyright
@@ -82,6 +91,7 @@ libpoke_modules="
   stdarg
   stdbool
   stddef
+  stpcpy
   strchrnul
   streq
   string-buffer
diff --git a/configure.ac b/configure.ac
index e40b3a4e..7ca26abb 100644
--- a/configure.ac
+++ b/configure.ac
@@ -98,11 +98,20 @@ dnl emitted in case no proper AWK is present.
 AX_CHECK_AWK_GENSUB([RAS_AWK=$AWK], [RAS_AWK=:])
 AC_SUBST([RAS_AWK])

+dnl REPL
+
+AC_CHECK_FUNCS([siglongjmp], break)
+
 dnl The Boehm-Weiser garbage collector

 PKG_PROG_PKG_CONFIG
 PKG_CHECK_MODULES(BDW_GC,[bdw-gc],[have_gc=yes],[have_gc=no])

+LIBS_BK="$LIBS"
+LIBS="$LIBS $BDW_GC_LIBS"
+AC_CHECK_FUNCS([GC_remove_roots],[HAVE_GC_REMOVE_ROOTS=yes])
+LIBS="$LIBS_BK"
+
 dnl The JSON-C library for the machine-interface

 AC_ARG_ENABLE([mi],
@@ -299,6 +308,10 @@ if test "x$have_gc" = "xno"; then
    AC_MSG_ERROR([can't find the Boehm GC library.  Please install it.])
 fi

+if test "x$HAVE_GC_REMOVE_ROOTS" = "x"; then
+   AC_MSG_WARN([Boehm GC does not implement GC_remove_roots on your platform; 
poke may leak roots, and thus memory.])
+fi
+
 if test "x$gl_cv_lib_readline" = "xno"; then
    AC_MSG_ERROR([can't find an usable libreadline.  Please install one.])
 fi
diff --git a/libpoke/pvm-alloc.c b/libpoke/pvm-alloc.c
index ab7bc9d3..5d121c6d 100644
--- a/libpoke/pvm-alloc.c
+++ b/libpoke/pvm-alloc.c
@@ -83,6 +83,8 @@ pvm_alloc_add_gc_roots (void *pointer, size_t nelems)
 void
 pvm_alloc_remove_gc_roots (void *pointer, size_t nelems)
 {
+#if defined HAVE_GC_REMOVE_ROOTS
   GC_remove_roots (pointer,
                    ((char*) pointer) + sizeof (void*) * nelems);
+#endif
 }
diff --git a/poke/pk-hserver.c b/poke/pk-hserver.c
index 873020f1..c1fca81f 100644
--- a/poke/pk-hserver.c
+++ b/poke/pk-hserver.c
@@ -27,6 +27,7 @@
 #include <sys/time.h>
 #include <sys/types.h>
 #include <sys/socket.h>
+#include <sys/select.h>
 #include <netinet/in.h>
 #include <arpa/inet.h>
 #include <netdb.h>
diff --git a/poke/pk-mi.c b/poke/pk-mi.c
index 64670f5c..81188d97 100644
--- a/poke/pk-mi.c
+++ b/poke/pk-mi.c
@@ -26,6 +26,7 @@
 #include <assert.h>
 #include <fcntl.h>
 #include <errno.h>
+#include <sys/select.h>

 #include "poke.h"

@@ -167,6 +168,7 @@ pk_mi_send_frame_msg (const char *payload)
 /* Set fd to non-blocking and return old flags or -1 on error. */
 static int pk_mi_fd_set_nonblocking (int fd)
 {
+#if defined HAVE_FCNTL
   int flags = fcntl (fd, F_GETFL, 0);

   if (flags >= 0 && (flags & O_NONBLOCK) == 0)
@@ -179,16 +181,21 @@ static int pk_mi_fd_set_nonblocking (int fd)
     perror ("fcntl");

   return flags;
+#else
+  return 0;
+#endif
 }

 /* Restore flags to fd if it was set to blocking previously. */
 static void pk_mi_fd_restore_blocking (int fd, int flags)
 {
+#if defined HAVE_FCNTL
   if (flags >= 0 && (flags & O_NONBLOCK) == 0)
     {
       if (fcntl (fd, F_SETFL, flags) < 0)
         perror ("fcntl");
     }
+#endif
 }

 /* This global is used to finalize the MI loop.  */
diff --git a/poke/pk-repl.c b/poke/pk-repl.c
index f01b22f3..e1062c56 100644
--- a/poke/pk-repl.c
+++ b/poke/pk-repl.c
@@ -41,8 +41,10 @@
 /* The thread that contains the non-local entry point for reentering
    the REPL.  */
 static pthread_t volatile ctrlc_thread;
+#if HAVE_SIGLONGJMP
 /* The non-local entry point for reentering the REPL.  */
 static sigjmp_buf /*volatile*/ ctrlc_buf;
+#endif
 /* When nonzero, ctrlc_thread and ctrlc_buf contain valid values.  */
 static int volatile ctrlc_buf_valid;

@@ -237,7 +239,9 @@ poke_sigint_handler (int sig)
           rl_cleanup_after_signal ();
           rl_line_buffer[rl_point = rl_end = rl_mark = 0] = 0;
           printf ("\n");
+#if HAVE_SIGLONGJMP
           siglongjmp (ctrlc_buf, 1);
+#endif
         }
     }
   else
@@ -348,7 +352,9 @@ pk_repl (void)
   rl_filename_quoting_function = escape_metacharacters;

   ctrlc_thread = pthread_self ();
+#if HAVE_SIGLONGJMP
   sigsetjmp (ctrlc_buf, 1);
+#endif
   ctrlc_buf_valid = 1;

   while (!poke_exit_p)
--
2.26.2