X-Git-Url: https://jxself.org/git/?a=blobdiff_plain;f=src%2Fread.c;h=0f6a63d840108567ed2180c37dbe70afca1b5df0;hb=e3dcc1d3966fb95a5a232daa193c6b5d89a06b7e;hp=57dd81f511d8f3538e73ee7efed7bd1bd7945029;hpb=8d55156675587a770c5654362bcbd3d2a98e4aa9;p=muddle-interpreter.git

diff --git a/src/read.c b/src/read.c
index 57dd81f..0f6a63d 100644
--- a/src/read.c
+++ b/src/read.c
@@ -1,5 +1,5 @@
 /*
-Copyright (C) 2017 Keziah Wesley
+Copyright (C) 2017-2018 Keziah Wesley
 
 You can redistribute and/or modify this file under the terms of the
 GNU Affero General Public License as published by the Free Software
@@ -18,6 +18,7 @@ License along with this file. If not, see
 
 #include "read.h"
 #include "object.h"
+#include "oblist.h"
 
 #include <assert.h>
 #include <stdio.h>
@@ -113,6 +114,66 @@ static uint32_t obj_get_fix32(const object *o) {
 }
 */
 
+static int
+read_num (const char *p, reader_stack * st)
+{
+  int i = 0;
+  // Use an unsigned intermediate to simplify overflow checks.
+  uint64_t x = 0;
+  // Disallow "number" composed of ancillary number components only.
+  bool gotdigits = false;
+  // Skip for now, later we'll check again to potentially negate.
+  if (p[0] == '-')
+    i++;
+  // TODO: asterisk-deliminated *octal*
+  // TODO: other bases?
+  for (; p[i]; i++)
+    {
+      if (p[i] >= '0' && p[i] <= '9')
+	{
+	  if (x * 10 + (p[i] - '0') < x)
+	    goto read_float;
+	  x = x * 10 + (p[i] - '0');
+	  gotdigits = true;
+	  continue;
+	}
+
+      // TODO: decimal points, exponent notation
+      // NB. a terminal decimal denotes a FIX
+      // NB. exponent notation doesn't necessarily indicate a float
+
+      // TODO: distinguish 'delimiter' characters that terminate
+      // number from 'identifier' chars that cause parsing to fail
+      // (and potentially be parsed as an atom)
+      break;
+    }
+  if (!gotdigits)
+    return 0;
+  if (p[0] != '-')
+    {
+      if (x <= INT32_MAX)
+	(--(st->pos))->fix32 = new_fix32 ((int32_t) x);
+      else if (x <= INT64_MAX)
+	(--(st->pos))->fix64 = new_fix64 (x);
+      else
+	goto read_float;
+    }
+  else
+    {
+      if (-x >= (uint64_t) INT32_MIN)
+	(--(st->pos))->fix32 = new_fix32 (0 - (int32_t) x);
+      else if (-x >= (uint64_t) INT64_MIN)
+	(--(st->pos))->fix64 = new_fix64 (0 - (int64_t) x);
+      else
+	goto read_float;
+    }
+  st->framelen++;
+  return i;
+read_float:
+  assert (0 && "unimplemented: promote num to float");
+  return i;
+}
+
 // stack[0..len]: objs in current list
 // stack[len]: parent len
 const char *
@@ -146,7 +207,10 @@ read_token (const char *p, reader_stack * st)
 	  }
 	*--(st->pos) = (object)
 	{
-	.fix32.type = type,.fix32.rest = 0,.fix32.val = st->framelen,};
+	  .fix32.type = type,.fix32.rest = 0,.fix32.val = (fix32_val)
+	  {
+	  .n = st->framelen}
+	,};
 	st->framelen = 0;
 	break;
       }
@@ -171,11 +235,10 @@ read_token (const char *p, reader_stack * st)
 	// pop frame, push new LIST
 	st->pos += st->framelen;
 	assert (st->pos->type == type);
-	st->framelen = st->pos->fix32.val + 1;
+	st->framelen = st->pos->fix32.val.n + 1;
 	// overwrite the frame marker with the collection it became
-	st->pos->list = (list_object)
-	{
-	.type = type,.rest = 0,.head = o};
+	st->pos->list = new_list (o);
+	st->pos->list.type = type;
 	break;
       }
     case ']':
@@ -187,21 +250,27 @@ read_token (const char *p, reader_stack * st)
 	uint32_t len = st->framelen;
 	st->pos += st->framelen;
 	assert (st->pos->type == EVALTYPE_VECTOR);
-	st->framelen = st->pos->fix32.val + 1;
+	st->framelen = st->pos->fix32.val.n + 1;
 	st->pos->vector = new_vector (h, len);
 	break;
       }
-    case '4':
+    default:
       {
-	p++;
-	// push fix obj, extending frame
-	(--(st->pos))->fix64 = new_fix64 (4);
-	st->framelen++;
-	break;
+	int n = read_num (p, st);
+	if (n)
+	  return p + n;
+
+	n = count_pname (p);
+	if (n > 0)
+	  {
+	    (--(st->pos))->atom = oblist_find_or_insert (root, p, n);
+	    st->framelen++;
+	    return p + n;
+	  }
+
+	fprintf (stderr, "read unimplemented for char: '%c'\n", *p);
+	assert (0 && "read unimplemented for char");
       }
-    default:
-      fprintf (stderr, "read unimplemented for char: '%c'\n", *p);
-      assert (0 && "read unimplemented for char");
     }
   return p;
 }