COMMON: fix broken implementation to avoid appending multiple kwTYPE_EOCs

Author: chrisws

samples/distro-examples/tests/output/uds.out

@@ -10,3 +10,4 @@ a.xfish.small=small
 a.xfish.big=big
 3
 2
+10

samples/distro-examples/tests/uds.bas

@@ -141,4 +141,27 @@ rem fill the var cache for testing in valgrind
 cache = {}
 for i = 0 to 8096
   cache[i] = "."
-next i
+next i
+
+'
+' regression modifying kwTYPE_EOC
+'
+func GridClass()
+  sub setCellValue(a)
+    ? a
+  end
+  local result = {}
+  result.setCellValue = @setCellValue
+  return result
+end
+func Game()
+  sub start()
+    self.grid.setCellValue(10)
+  end
+  local result = {}
+  result.grid = GridClass()
+  result.start = @start
+  return result
+end
+g = Game()
+g.start()

src/common/bc.c

@@ -9,9 +9,6 @@
 
 #include "common/bc.h"
 #include "common/smbas.h"
-#if defined(_UnixOS)
-#include <assert.h>
-#endif
 
 /*
  * Create a bytecode segment
@@ -34,6 +31,8 @@ void bc_destroy(bc_t *bc) {
   bc->size = 0;
   bc->count = 0;
   bc->cp = 0;
+  bc->eoc_position = 0;
+  bc->line_position = 0;
 }
 
 /*
@@ -60,13 +59,6 @@ void bc_add1(bc_t *bc, char code) {
   bc->count++;
 }
 
-/*
- * change one command
- */
-void bc_store1(bc_t *bc, bcip_t offset, byte code) {
-  bc->ptr[offset] = code;
-}
-
 /*
  * add one uint32_t
  */
@@ -254,6 +246,20 @@ void bc_eoc(bc_t *bc) {
   }
 }
 
+/*
+ * pops any EOC mark at the current position
+ */
+int bc_pop_eoc(bc_t *bc) {
+  int result;
+  if (bc->eoc_position > 0 && bc->eoc_position == bc->count - 1) {
+    bc->eoc_position = 0;
+    result = (bc->ptr[--bc->count] == kwTYPE_EOC);
+  } else {
+    result = 0;
+  }
+  return result;
+}
+
 /*
  * appends the src to dst
  */

src/common/bc.h

@@ -81,16 +81,6 @@ void bc_resize(bc_t *bc, uint32_t newsize);
  */
 void bc_add1(bc_t *bc, char code);
 
-/**
- * @ingroup scan
- *
- * put 1 byte to specified offset
- *
- * @param bc the bc structure
- * @param code the byte
- */
-void bc_store1(bc_t *bc, bcip_t offset, byte code);
-
 /**
  * @ingroup scan
  *
@@ -128,6 +118,16 @@ char *bc_store_string(bc_t *bc, char *src);
  */
 void bc_eoc(bc_t *bc);
 
+/**
+ * @ingroup scan
+ *
+ * pops any EOC mark at the current position
+ *
+ * @param bc the bc segment
+ * @return whether kwTYPE_EOC was popped
+ */
+int bc_pop_eoc(bc_t *bc);
+
 /**
  * @ingroup scan
  *

src/common/blib.c

@@ -1009,6 +1009,9 @@ bcip_t cmd_push_args(int cmd, bcip_t goto_addr, bcip_t rvid) {
     do {
       byte code = code_peek();  // get next BC
       switch (code) {
+      case kwTYPE_LINE:
+        ready = 1;           // finish flag
+        break;
       case kwTYPE_EOC:       // end of an expression (parameter)
         code_skipnext();     // ignore it
         break;
@@ -1097,6 +1100,9 @@ void cmd_call_unit_udp(int cmd, int udp_tid, bcip_t goto_addr, bcip_t rvid) {
     do {
       byte code = code_peek();    // get next BC
       switch (code) {
+      case kwTYPE_LINE:
+        ready = 1;           // finish flag
+        break;
       case kwTYPE_EOC:       // end of an expression (parameter)
         code_skipnext();     // ignore it
         break;

src/common/scan.c

@@ -1849,7 +1849,12 @@ char *comp_array_params(char *src, char exitChar) {
             *se = '\0';
             bc_add_code(&comp_prog, kwTYPE_LEVEL_BEGIN);
             comp_expression(ss, 0);
-            bc_store1(&comp_prog, comp_prog.count - 1, kwTYPE_LEVEL_END);
+            // overwrite kwTYPE_EOC with kwTYPE_LEVEL_END
+            if (!bc_pop_eoc(&comp_prog)) {
+              sc_raise(ERR_UNSUPPORTED);
+            }
+            bc_add_code(&comp_prog, kwTYPE_LEVEL_END);
+            comp_prog.eoc_position = 0;
             *ss = ssSave;
             *se = seSave;
             ss = se = NULL;
@@ -2812,6 +2817,24 @@ int comp_text_line_command(bid_t idx, int decl, int sharp, char *last_cmd) {
   return result;
 }
 
+void add_line_no() {
+  if (comp_prog.line_position == 0 ||
+      comp_prog.line_position != (comp_prog.count - KW_TYPE_LINE_BYTES)) {
+    // not an adjoining kwTYPE_LINE
+    if (!opt_autolocal && comp_prog.eoc_position == comp_prog.count - 1) {
+      // overwrite any adjoining kwTYPE_EOC (can't do this with autolocal)
+      if (!bc_pop_eoc(&comp_prog)) {
+        sc_raise(ERR_UNSUPPORTED);
+      }
+    }
+
+    // prevent adjoining kwTYPE_LINEs
+    comp_prog.line_position = comp_prog.count;
+    bc_add_code(&comp_prog, kwTYPE_LINE);
+    bc_add_addr(&comp_prog, comp_line);
+  }
+}
+
 /*
  * Pass 1: scan source line
  */
@@ -2870,20 +2893,7 @@ void comp_text_line(char *text, int addLineNo) {
     return;
   }
   if (addLineNo) {
-    // add debug info: line-number
-    if (comp_prog.line_position == 0 ||
-        comp_prog.line_position != (comp_prog.count - KW_TYPE_LINE_BYTES)) {
-      // not an adjoining kwTYPE_LINE
-      if (!opt_autolocal && comp_prog.eoc_position == comp_prog.count - 1) {
-        // overwrite any adjoining kwTYPE_EOC (can't do this with autolocal)
-        comp_prog.count--;
-      }
-      // prevent kwTYPE_EOC from being appended to this kwTYPE_LINE
-      comp_prog.eoc_position = comp_prog.count;
-      comp_prog.line_position = comp_prog.count;
-      bc_add_code(&comp_prog, kwTYPE_LINE);
-      bc_add_addr(&comp_prog, comp_line);
-    }
+    add_line_no();
   }
   if (idx == -1) {
     idx = comp_is_proc(comp_bc_name);
@@ -3719,13 +3729,15 @@ bcip_t comp_optimise_let(bcip_t ip, byte kw_opr, char sep, byte opt_kw) {
   bcip_t ip_next = ip + 1;
   if (comp_prog.ptr[ip_next] == kwTYPE_VAR) {
     ip_next += 1 + sizeof(bcip_t);
-    while (ip_next < comp_prog.count && comp_prog.ptr[ip_next] != kwTYPE_EOC) {
+    while (ip_next < comp_prog.count && comp_prog.ptr[ip_next] != kwTYPE_EOC
+           && comp_prog.ptr[ip_next] != kwTYPE_LINE) {
       if (comp_prog.ptr[ip_next] == kw_opr &&
           comp_prog.ptr[ip_next + 1] == sep) {
         ip_next += 2;
         if (ip_next < comp_prog.count &&
             comp_prog.ptr[ip_next] == kwTYPE_VAR &&
-            comp_prog.ptr[ip_next + 1 + sizeof(bcip_t)] == kwTYPE_EOC) {
+            (comp_prog.ptr[ip_next + 1 + sizeof(bcip_t)] == kwTYPE_EOC ||
+             comp_prog.ptr[ip_next + 1 + sizeof(bcip_t)] == kwTYPE_LINE)) {
           comp_prog.ptr[ip] = opt_kw;
           ip = ip_next;
         }