Implement open_pipev in terms of popen for Windows which

does not have for or exec.  We could use CreateProcess and CreatePipe,
et cetera, but it won't buy us anything because the whole point
of this function is to improve the argument passing, and CreateProcess
takes a single command line string, not too different from popen.

* stream.c (pipev_close, make_pipev_stream): Surrounded with
HAVE_FORK_STUFF ifdef.
(pipe_close): Choice of close strategy conditional on HAVE_FORK_STUFF.
(open_pipev): Conditionally defined in two ways now.
(win_escape_arg, win_make_cmdline): New static functions.

1 files changed, 65 insertions, 1 deletions

diff --git a/stream.c b/stream.c
index 08ad823c..72b819ff 100644
--- a/stream.c
+++ b/stream.c
@@ -274,6 +274,7 @@ static struct strm_ops stdio_ops = {
   stdio_flush
 };
 
+#if HAVE_FORK_STUFF
 static int pipevp_close(FILE *f, pid_t pid)
 {
   int status;
@@ -282,13 +283,18 @@ static int pipevp_close(FILE *f, pid_t pid)
     ;
   return status;
 }
+#endif
 
 static val pipe_close(val stream, val throw_on_error)
 {
   struct stdio_handle *h = (struct stdio_handle *) stream->co.handle;
 
   if (h->f != 0) {
+#if HAVE_FORK_STUFF
     int status = h->pid != 0 ? pipevp_close(h->f, h->pid) : pclose(h->f);
+#else
+    int status = pclose(h->f);
+#endif
     h->f = 0;
 
     if (status != 0 && throw_on_error) {
@@ -730,6 +736,7 @@ val make_pipe_stream(FILE *f, val descr, val input, val output)
   return stream;
 }
 
+#if HAVE_FORK_STUFF
 static val make_pipevp_stream(FILE *f, val descr, pid_t pid)
 {
   struct stdio_handle *h = (struct stdio_handle *) chk_malloc(sizeof *h);
@@ -740,7 +747,7 @@ static val make_pipevp_stream(FILE *f, val descr, pid_t pid)
   h->pid = pid;
   return stream;
 }
-
+#endif
 
 val make_string_input_stream(val string)
 {
@@ -1529,6 +1536,7 @@ val open_pipe(val path, val mode_str)
   return make_pipe_stream(f, path, input, output);
 }
 
+#if HAVE_FORK_STUFF
 val open_pipevp(val name, val mode_str, val args)
 {
   int input = equal(mode_str, lit("r")) || equal(mode_str, lit("rb"));
@@ -1600,6 +1608,62 @@ val open_pipevp(val name, val mode_str, val args)
     return make_pipevp_stream(f, name, pid);
   }
 }
+#else
+
+static val win_escape_arg(val str)
+{
+  int bscount = 0, i;
+  const wchar_t *s;
+  val out = string(L"");
+
+  for (s = c_str(str); *s; s++) {
+    switch (*s) {
+    case '"':
+      for (i = 0; i < bscount; i++)
+        string_extend(out, lit("\\\\"));
+      string_extend(out, lit("\\\""));
+      bscount = 0;
+      break;
+    case '\\':
+      bscount++;
+      break;
+    default:
+      for (i = 0; i < bscount; i++)
+        string_extend(out, lit("\\"));
+      string_extend(out, chr(*s));
+      bscount = 0;
+      break;
+    }
+  }
+
+  for (i = 0; i < bscount; i++)
+    string_extend(out, lit("\\"));
+
+  return out;
+}
+
+static val win_make_cmdline(val args)
+{
+  val out = string(L"");
+
+  for (; args; args = cdr(args)) {
+    string_extend(out, lit("\""));
+    string_extend(out, win_escape_arg(car(args)));
+    if (cdr(args))
+      string_extend(out, lit("\" "));
+    else
+      string_extend(out, lit("\""));
+  }
+
+  return out;
+}
+
+val open_pipevp(val name, val mode_str, val args)
+{
+  val win_cmdline = win_make_cmdline(cons(name, args));
+  return open_pipe(win_cmdline, mode_str);
+}
+#endif
 
 void stream_init(void)
 {