X-Git-Url: http://git.subgeniuskitty.com/vvhitespace/.git/blobdiff_plain/eea0db3fe145a963cc85df6e5785c9bcc54b63ab..45abb94e7cc7357b082f9ffda11077e2c606645e:/vv_interpreter.c

diff --git a/vv_interpreter.c b/vv_interpreter.c
index 337fd61..1d5d906 100644
--- a/vv_interpreter.c
+++ b/vv_interpreter.c
@@ -118,10 +118,15 @@ parse_label(uint8_t * code, size_t * pc)
     uint8_t c;
     while ((c = code[(*pc)++]) != '\n') {
         label = label << 1;
-        if (c == ' ') label++;
+        if (c == '\t') label++;
     }
-    // TODO: Where should I handle attempts to access an unitialized label?
-    //       For now, leave it undefined in a nasal demon sense.
+    return label;
+}
+
+uint16_t
+check_label(size_t * labels, uint16_t label, size_t * pc)
+{
+    if(!labels[label]) ws_die(pc, "uninitialized label (forgot an include?)");
     return label;
 }
 
@@ -130,11 +135,10 @@ populate_labels(size_t * labels, uint8_t * code, size_t code_size)
 {
     size_t cp = 0;
     while (cp <= code_size) {
-        if (code[cp] == '\v') {
+        if (code[cp++] == '\v') {
             uint16_t temp_label = parse_label(code, &cp);
             labels[temp_label] = cp;
         }
-        cp++;
     }
 }
 
@@ -248,6 +252,7 @@ void
 process_imp_flowcontrol(uint8_t * code, size_t * pc, int64_t ** sp, size_t * labels,
                         size_t ** rsp)
 {
+    size_t temp_pc;
     switch (next_code_byte(code,pc)) {
         case '\n':
             /* Technically another LF is required but we ignore it. */
@@ -266,15 +271,13 @@ process_imp_flowcontrol(uint8_t * code, size_t * pc, int64_t ** sp, size_t * lab
                         break;
                     case '\t':
                         /* Call a subroutine. */
-                        {
-                            size_t temp_pc = labels[parse_label(code, pc)];
-                            *((*rsp)++) = *pc;
-                            *pc = temp_pc;
-                        }
+                        temp_pc = labels[check_label(labels, parse_label(code, pc), pc)];
+                        *((*rsp)++) = *pc;
+                        *pc = temp_pc;
                         break;
                     case '\n':
                         /* Jump unconditionally to a label. */
-                        *pc = labels[parse_label(code, pc)];
+                        *pc = labels[check_label(labels, parse_label(code, pc), pc)];
                         break;
                     default:
                         ws_die(pc, "malformed flow control IMP");
@@ -287,11 +290,13 @@ process_imp_flowcontrol(uint8_t * code, size_t * pc, int64_t ** sp, size_t * lab
                 switch (next_code_byte(code,pc)) {
                     case ' ':
                         /* Jump to a label if TOS == 0 */
-                        if (stack_pop(sp) == 0) *pc = labels[parse_label(code, pc)];
+                        temp_pc = labels[check_label(labels, parse_label(code, pc), pc)];
+                        if (stack_pop(sp) == 0) *pc = temp_pc;
                         break;
                     case '\t':
                         /* Jump to a label if TOS < 0. */
-                        if (stack_pop(sp) < 0) *pc = labels[parse_label(code, pc)];
+                        temp_pc = labels[check_label(labels, parse_label(code, pc), pc)];
+                        if (stack_pop(sp) < 0) *pc = temp_pc;
                         break;
                     case '\n':
                         /* Return from subroutine. */