shithub: rgbds

--- a/include/asm/symbol.h

+++ b/include/asm/symbol.h

@@ -140,6 +140,7 @@

 struct Symbol *sym_AddMacro(char const *symName, int32_t defLineNo, char *body, size_t size);

 struct Symbol *sym_Ref(char const *symName);

 struct Symbol *sym_AddString(char const *symName, char const *value);

+struct Symbol *sym_RedefString(char const *symName, char const *value);

 void sym_Purge(char const *symName);

 void sym_Init(time_t now);

--- a/src/asm/lexer.c

+++ b/src/asm/lexer.c

@@ -270,6 +270,7 @@

 	{"RW", T_POP_RW},

 	{"EQU", T_POP_EQU},

 	{"EQUS", T_POP_EQUS},

+	{"REDEF", T_POP_REDEF},

 	/*  Handled before in list of CPU instructions */

 	/* {"SET", T_POP_SET}, */

@@ -490,7 +491,7 @@

 	uint16_t children[0x60 - ' '];

 	struct KeywordMapping const *keyword;

 /* Since the keyword structure is invariant, the min number of nodes is known at compile time */

-} keywordDict[352] = {0}; /* Make sure to keep this correct when adding keywords! */

+} keywordDict[356] = {0}; /* Make sure to keep this correct when adding keywords! */

 /* Convert a char into its index into the dict */

 static inline uint8_t dictIndex(char c)

--- a/src/asm/parser.y

+++ b/src/asm/parser.y

@@ -425,6 +425,7 @@

 %token	T_POP_FATAL

 %token	T_POP_ASSERT T_POP_STATIC_ASSERT

 %token	T_POP_PURGE

+%token	T_POP_REDEF

 %token	T_POP_POPS

 %token	T_POP_PUSHS

 %token	T_POP_POPO

@@ -645,6 +646,7 @@

 		| warn

 		| assert

 		| purge

+		| redef

 		| pops

 		| pushs

 		| popo

@@ -874,6 +876,15 @@

 			lexer_ToggleStringExpansion(false);

 		} purge_list {

 			lexer_ToggleStringExpansion(true);

+		}

+;

+redef		: T_POP_REDEF {

+			lexer_ToggleStringExpansion(false);

+		} scoped_id {

+			lexer_ToggleStringExpansion(true);

+		} T_POP_EQUS string {

+			sym_RedefString($3, $6);

--- a/src/asm/rgbasm.5

+++ b/src/asm/rgbasm.5

@@ -929,7 +929,7 @@

 .Ic = ,

 defines constant symbols like

 .Ic EQU ,

-but those constants can be re-defined.

+but those constants can be redefined.

 This is useful for variables in macros, for counters, etc.

 .Bd -literal -offset indent

 ARRAY_SIZE EQU 4

@@ -1008,7 +1008,22 @@

 Note that colons

 .Ql \&:

 following the name are not allowed.

+.Pp

 String equates can't be exported or imported.

+.Pp

+String equates, like

+.Ic EQU

+constants, cannot be redefined.

+However, the

+.Ic REDEF

+keyword will define or redefine a string symbol.

+For example:

+.Bd -literal -offset indent

+s EQUS "Hello, "

+REDEF s EQUS "{s}world!"

+; prints "Hello, world!"

+PRINTT "{s}\n"

+.Ed

.Pp

 .Sy Important note :

An

--- a/src/asm/symbol.c

+++ b/src/asm/symbol.c

@@ -222,6 +222,19 @@

 		fatalerror("Symbol name is too long: '%s%s'\n", scopeName, localName);

+static void assignStringSymbol(struct Symbol *sym, char const *value)

+{

+	char *string = strdup(value);

+	if (string == NULL)

+		fatalerror("No memory for string equate: %s\n", strerror(errno));

+	sym->type = SYM_EQUS;

+	/* TODO: use other fields */

+	sym->macro = string;

+	sym->macroSize = strlen(string);

+}

 struct Symbol *sym_FindExactSymbol(char const *name)

 	return hash_GetElement(symbols, name);

@@ -283,6 +296,11 @@

 		if (symbol->name == labelScope)

 			labelScope = NULL;

+		/*

+		 * FIXME: this leaks symbol->macro for SYM_EQUS and SYM_MACRO, but this can't

+		 * free(symbol->macro) because the expansion may be purging itself.

+		 */

 		hash_RemoveElement(symbols, symbol->name);

 		/* TODO: ideally, also unref the file stack nodes */

 		free(symbol);

@@ -390,17 +408,30 @@

 struct Symbol *sym_AddString(char const *symName, char const *value)

 	struct Symbol *sym = createNonrelocSymbol(symName);

-	size_t len = strlen(value);

-	char *string = malloc(len + 1);

-	if (string == NULL)

-		fatalerror("No memory for string equate: %s\n", strerror(errno));

-	strcpy(string, value);

+	assignStringSymbol(sym, value);

-	sym->type = SYM_EQUS;

-	/* TODO: use other fields */

-	sym->macroSize = len;

-	sym->macro = string;

+	return sym;

+}

+struct Symbol *sym_RedefString(char const *symName, char const *value)

+{

+	struct Symbol *sym = sym_FindExactSymbol(symName);

+	if (!sym) {

+		sym = createsymbol(symName);

+	} else if (sym->type != SYM_EQUS) {

+		error("'%s' already defined as non-EQUS at ", symName);

+		dumpFilename(sym);

+		putc('\n', stderr);

+	}

+	/*

+	 * FIXME: this leaks the previous sym->macro value, but this can't

+	 * free(sym->macro) because the expansion may be redefining itself.

+	 */

+	assignStringSymbol(sym, value);

 	return sym;

--- /dev/null

+++ b/test/asm/redef-equs.asm

@@ -1,0 +1,23 @@

+s EQUS "Hello, "

+REDEF s EQUS "{s}world!"

+; prints "Hello, world!"

+PRINTT "{s}\n"

+list: MACRO

+LIST_NAME EQUS "\1"

+REDEF {LIST_NAME} EQUS "["

+REPT _NARG - 1

+REDEF {LIST_NAME} EQUS "{{LIST_NAME}}\2;"

+SHIFT

+ENDR

+REDEF {LIST_NAME} EQUS "{{LIST_NAME}}]"

+PURGE LIST_NAME

+ENDM

+	list FOO

+	PRINTT "{FOO}\n"

+	list FOO, 1, A, 2, B

+	PRINTT "{FOO}\n"

+N EQU 42

+REDEF N EQUS "X"

--- /dev/null

+++ b/test/asm/redef-equs.err

@@ -1,0 +1,3 @@

+ERROR: redef-equs.asm(23):

+    'N' already defined as non-EQUS at redef-equs.asm(22)

+error: Assembly aborted (1 errors)!

--- /dev/null

+++ b/test/asm/redef-equs.out

@@ -1,0 +1,3 @@

+Hello, world!

+[]

+[1;A;2;B;]