M xywasm.c → xywasm.c

@@ -19,10 +19,16 @@ #define PSH 0x01
 
 typedef struct
 {
+    enum
+    {
+        SRC_FILE,
+        SRC_STRING
+    } src;
     int line;
     int column;
     char *file;
     FILE *fp;
+    const char *sp;
 } xyw_context;
 
 typedef enum
@@ -108,6 +114,7 @@ while (*str)
     {
         *dictnext++ = *str++;
     }
+    *dictnext++ = '\0';
     return o;
 }
 
@@ -148,8 +155,11 @@ // Not found, store the new string and return its address
     return dict_store(str);
 }
 
+//// Forward declarations
+static xyw_token_terminator next_token(xyw_context *ctx);
+static int assemble_string(xyw_context *ctx, const char *text);
+
 //// Utilities
-static xyw_token_terminator next_token(xyw_context *ctx);
 
 static int find_symbol(char *name)
 {
@@ -309,8 +319,23 @@ static int process_comment(xyw_context *ctx)
 {
     char c;
     // Process single-line comment
-    while (fread(&c, 1, 1, ctx->fp) == 1)
+    while (1)
     {
+        if (ctx->src == SRC_FILE)
+        {
+            if (fread(&c, 1, 1, ctx->fp) != 1)
+            {
+                break;
+            }
+        }
+        else
+        {
+            if (!ctx->sp || *ctx->sp == '\0')
+            {
+                break;
+            }
+            c = *ctx->sp++;
+        }
         // Ignore all characters until end of line
         if (c == '\n')
         {
@@ -531,7 +556,10 @@ {
             xyw_symbol *sym = &symbols[i];
             if (sym->type == SYMBOL_TYPE_MACRO)
             {
-                // TODO: Expand macro
+                printf("-> Macro:\t%s\n", sym->contents);
+                assemble_string(ctx, sym->contents);
+                ctx->src = SRC_FILE;
+                ctx->sp = NULL;
             }
             else if (sym->type == SYMBOL_TYPE_LABEL)
             {
@@ -548,7 +576,7 @@ }
         else
         {
             // Store reference to be resolved later
-            printf("-> Ref:\t%s\n", token);
+            printf("-> Reference:\t%s\n", token);
             if (ref(ctx, token) != 0)
             {
                 return -1;
@@ -668,8 +696,23 @@ printf("Directive:\t.macro %s\n", token);
     char c;
     char contents[DIRECTIVE_CONTENT_MAX_LENGTH];
     int length = 0;
-    while (fread(&c, 1, 1, ctx->fp))
+    while (1)
     {
+        if (ctx->src == SRC_FILE)
+        {
+            if (fread(&c, 1, 1, ctx->fp) != 1)
+            {
+                break;
+            }
+        }
+        else
+        {
+            if (!ctx->sp || *ctx->sp == '\0')
+            {
+                break;
+            }
+            c = *ctx->sp++;
+        }
         if (c == '\n')
         {
             ctx->line++;
@@ -690,8 +733,6 @@ ctx->column++;
         contents[length++] = c;
         contents[length] = '\0';
     }
-    // TODO: remove
-    printf("Macro contents:\t%s\n", contents);
     macro(ctx, token, contents);
     return 0;
 }
@@ -788,8 +829,24 @@ char c;
     int in_string = 0;
     token_length = 0;
     token[0] = '\0';
-    while (fread(&c, 1, 1, ctx->fp) == 1)
+    while (1)
     {
+        // Read next character from active source
+        if (ctx->src == SRC_FILE)
+        {
+            if (fread(&c, 1, 1, ctx->fp) != 1)
+            {
+                break;
+            }
+        }
+        else
+        {
+            if (!ctx->sp || *ctx->sp == '\0')
+            {
+                break;
+            }
+            c = *ctx->sp++;
+        }
         if (c == '\n')
         {
             if (in_string)
@@ -862,7 +919,7 @@ return TOKEN_END_EOF;
 }
 
 // Read a file and process its tokens
-static int process_file(xyw_context *ctx)
+static int assemble_file(xyw_context *ctx)
 {
     ctx->fp = fopen(ctx->file, "r");
     if (!ctx->fp)
@@ -870,6 +927,9 @@ {
         error("Could not open file");
         return -1;
     }
+    // Set source mode to file
+    ctx->src = SRC_FILE;
+    ctx->sp = NULL;
     int r;
     while (1)
     {
@@ -887,6 +947,27 @@ fclose(ctx->fp);
     return r;
 }
 
+// Process tokens from an in-memory string buffer (mainly for macro body)
+static int assemble_string(xyw_context *ctx, const char *text)
+{
+    ctx->src = SRC_STRING;
+    ctx->sp = text;
+    int r;
+    while (1)
+    {
+        r = next_token(ctx);
+        if (r == TOKEN_END_EOF || r == TOKEN_END_INVALID)
+        {
+            break;
+        }
+        if (process_token(ctx) != 0)
+        {
+            break;
+        }
+    }
+    return r;
+}
+
 ///// Public API
 
 int xyw_assemble(const char *input, const char *output)
@@ -895,7 +976,7 @@ xyw_context ctx;
     ctx.file = (char *)input;
     ctx.line = 1;
     ctx.column = 1;
-    if (process_file(&ctx) != 0)
+    if (assemble_file(&ctx) != 0)
     {
         return -1;
     }