gzio: support more modes in open-file.

* gzio.c (w_gzopen_mode): Use w_open_mode if available, in order
to support most of the flags (including "x" which Zlib has,
but which we are not passing through).

* stream.c (w_open_mode): New function formed from w_fopen_mode
content.
(w_fopen_mode): Call w_open_mode.

* stream.c (w_open_mode): Declared.

4 files changed, 49 insertions, 3 deletions

diff --git a/gzio.c b/gzio.c
index fc025e9a..ef1e21ba 100644
--- a/gzio.c
+++ b/gzio.c
@@ -479,6 +479,13 @@ gzFile w_gzopen_mode(const wchar_t *wname, const wchar_t *wmode,
     uw_throwf(file_error_s,
               lit("~a: gzip stream cannot both read and write"), self, nao);
   }
+
+#if HAVE_FCNTL
+  {
+    int fd = w_open_mode(wname, m);
+    return (fd < 0) ? NULL : w_gzdopen_mode(fd, wmode, m, self);
+  }
+#else
   {
     char *name = utf8_dup_to(wname);
     char *mode = utf8_dup_to(wmode);
@@ -487,6 +494,34 @@ gzFile w_gzopen_mode(const wchar_t *wname, const wchar_t *wmode,
     free(mode);
     return f;
   }
+#endif
+}
+
+gzFile w_gzdopen_mode(int fd, const wchar_t *wmode,
+                      const struct stdio_mode m, val self)
+{
+  if (m.buforder >= 0 || m.nonblock || m.notrunc || m.unbuf ||
+      m.linebuf || m.interactive)
+  {
+    goto badmode;
+  }
+
+  if (m.read && m.write) {
+    uw_throwf(file_error_s,
+              lit("~a: gzip stream cannot both read and write"), self, nao);
+  }
+
+  {
+    char *mode = utf8_dup_to(wmode);
+    gzFile f = gzdopen(fd, mode);
+    free(mode);
+    if (f)
+      return f;
+  }
+
+badmode:
+  uw_throwf(file_error_s,
+            lit("~a: invalid modes for gzip stream"), self, nao);
 }
 
 val make_gzio_stream(gzFile f, int fd, val descr, int is_output)
diff --git a/gzio.h b/gzio.h
index bbcd1e1a..2f9cf164 100644
--- a/gzio.h
+++ b/gzio.h
@@ -30,4 +30,6 @@ val gzio_stream_s;
 void gzio_init(void);
 gzFile w_gzopen_mode(const wchar_t *wname, const wchar_t *wmode,
                      const struct stdio_mode m, val self);
+gzFile w_gzdopen_mode(int fd, const wchar_t *wmode,
+                      const struct stdio_mode m, val self);
 val make_gzio_stream(gzFile f, int fd, val descr, int is_output);
diff --git a/stream.c b/stream.c
index d3118955..e336d35f 100644
--- a/stream.c
+++ b/stream.c
@@ -1127,10 +1127,9 @@ static struct strm_ops stdio_ops =
 static struct strm_ops stdio_sock_ops;
 #endif
 
-static FILE *w_fopen_mode(const wchar_t *wname, const wchar_t *mode,
-                          const struct stdio_mode m)
-{
 #if HAVE_FCNTL
+int w_open_mode(const wchar_t *wname, const struct stdio_mode m)
+{
   char *name = utf8_dup_to(wname);
   size_t nsiz = strlen(name) + 1;
   int flags = (if3(m.read && m.write, O_RDWR, 0) |
@@ -1150,6 +1149,15 @@ static FILE *w_fopen_mode(const wchar_t *wname, const wchar_t *mode,
   fd = open(stkname, flags, 0666);
   sig_restore_enable;
 
+  return fd;
+}
+#endif
+
+static FILE *w_fopen_mode(const wchar_t *wname, const wchar_t *mode,
+                          const struct stdio_mode m)
+{
+#if HAVE_FCNTL
+  int fd = w_open_mode(wname, m);
   return (fd < 0) ? NULL : w_fdopen(fd, mode);
 #else
   /* TODO: detect if fopen supports "x" in mode */
diff --git a/stream.h b/stream.h
index 83534617..b735dd07 100644
--- a/stream.h
+++ b/stream.h
@@ -167,6 +167,7 @@ void fill_stream_ops(struct strm_ops *ops);
 void stream_print_op(val stream, val out, val pretty, struct strm_ctx *);
 void stream_mark_op(val stream);
 void stream_destroy_op(val stream);
+int w_open_mode(const wchar_t *wname, const struct stdio_mode m);
 struct stdio_mode parse_mode(val mode_str, struct stdio_mode m_dfl, val self);
 val normalize_mode(struct stdio_mode *m, val mode_str,
                    struct stdio_mode m_dfl, val self);