Add Glulxe and Git. They compile but don't work yet.

[rodin/chimara.git] / interpreters / glulxe / files.c

diff --git a/interpreters/glulxe/files.c b/interpreters/glulxe/files.c
new file mode 100644 (file)
index 0000000..d575c98
--- /dev/null
+++ b/interpreters/glulxe/files.c
@@ -0,0 +1,89 @@
+/* files.c: Glulxe file-handling code.
+    Designed by Andrew Plotkin <erkyrath@eblong.com>
+    http://eblong.com/zarf/glulx/index.html
+*/
+
+#include "glk.h"
+#include "gi_blorb.h"
+#include "glulxe.h"
+
+/* is_gamefile_valid():
+   Check guess what.
+*/
+int is_gamefile_valid()
+{
+  unsigned char buf[8];
+  int res;
+  glui32 version;
+
+  glk_stream_set_position(gamefile, gamefile_start, seekmode_Start);
+  res = glk_get_buffer_stream(gamefile, (char *)buf, 8);
+
+  if (res != 8) {
+    fatal_error("This is too short to be a valid Glulx file.");
+    return FALSE;
+  }
+
+  if (buf[0] != 'G' || buf[1] != 'l' || buf[2] != 'u' || buf[3] != 'l') {
+    fatal_error("This is not a valid Glulx file.");
+    return FALSE;
+  }
+
+  /* We support version 2.0 through 3.1.*. */
+
+  version = Read4(buf+4);
+  if (version < 0x20000) {
+    fatal_error("This Glulx file is too old a version to execute.");
+    return FALSE;
+  }
+  if (version >= 0x30200) {
+    fatal_error("This Glulx file is too new a version to execute.");
+    return FALSE;
+  }
+
+  return TRUE;
+}
+
+/* locate_gamefile: 
+   Given that gamefile contains a Glk stream, which may be a Glulx
+   file or a Blorb archive containing one, locate the beginning and
+   end of the Glulx data.
+*/
+int locate_gamefile(int isblorb)
+{
+  if (!isblorb) {
+    /* The simple case. A bare Glulx file was opened, so we don't use
+       Blorb at all. */
+    gamefile_start = 0;
+    glk_stream_set_position(gamefile, 0, seekmode_End);
+    gamefile_len = glk_stream_get_position(gamefile);
+    return TRUE;
+  }
+  else {
+    /* A Blorb file. We now have to open it and find the Glulx chunk. */
+    giblorb_err_t err;
+    giblorb_result_t blorbres;
+    giblorb_map_t *map;
+
+    err = giblorb_set_resource_map(gamefile);
+    if (err) {
+      init_err = "This Blorb file seems to be invalid.";
+      return FALSE;
+    }
+    map = giblorb_get_resource_map();
+    err = giblorb_load_resource(map, giblorb_method_FilePos, 
+      &blorbres, giblorb_ID_Exec, 0);
+    if (err) {
+      init_err = "This Blorb file does not contain an executable Glulx chunk.";
+      return FALSE;
+    }
+    if (blorbres.chunktype != giblorb_make_id('G', 'L', 'U', 'L')) {
+      init_err = "This Blorb file contains an executable chunk, but it is not a Glulx file.";
+      return FALSE;
+    }
+    gamefile_start = blorbres.data.startpos;
+    gamefile_len = blorbres.length;
+    return TRUE;
+  }
+}
+