--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/lwasm/macro.c	Wed Jan 19 22:27:17 2011 -0700
@@ -0,0 +1,292 @@
+/*
+macro.c
+Copyright © 2008 William Astle
+
+This file is part of LWASM.
+
+LWASM is free software: you can redistribute it and/or modify it under the
+terms of the GNU General Public License as published by the Free Software
+Foundation, either version 3 of the License, or (at your option) any later
+version.
+
+This program is distributed in the hope that it will be useful, but WITHOUT
+ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+more details.
+
+You should have received a copy of the GNU General Public License along with
+this program. If not, see <http://www.gnu.org/licenses/>.
+
+Contains stuff associated with macro processing
+*/
+
+#include <ctype.h>
+#include <stdlib.h>
+#include <string.h>
+#include <stdio.h>
+
+#include <lw_alloc.h>
+#include <lw_string.h>
+
+#include "lwasm.h"
+#include "input.h"
+#include "instab.h"
+
+PARSEFUNC(pseudo_parse_macro)
+{
+	macrotab_t *m;
+	
+	l -> len = 0;
+	
+	if (as -> skipcond)
+	{
+		as -> skipmacro = 1;
+		return;
+	}
+	
+	if (as -> inmacro)
+	{
+		lwasm_register_error(as, l, "Attempt to define a macro inside a macro");
+		return;
+	}
+	
+	if (!(l -> sym))
+	{
+		lwasm_register_error(as, l, "Missing macro name");
+		return;
+	}
+
+	for (m = as -> macros; m; m = m -> next)
+	{
+		if (!strcmp(m -> name, l -> sym))
+			break;
+	}
+	if (m)
+	{
+		lwasm_register_error(as, l, "Duplicate macro definition");
+		return;
+	}
+	
+	m = lw_alloc(sizeof(macrotab_t));
+	m -> name = lw_strdup(l -> sym);
+	m -> next = as -> macros;
+	m -> lines = NULL;
+	m -> numlines = 0;
+	as -> macros = m;
+	
+	while (**p && !isspace(**p))
+		(*p)++;
+	
+	as -> inmacro = 1;
+}
+
+PARSEFUNC(pseudo_parse_endm)
+{
+	l -> len = 0;
+
+	if (as -> skipcond)
+	{
+		as -> skipmacro = 0;
+		return;
+	}
+	
+	if (!as -> inmacro)
+	{
+		lwasm_register_error(as, l, "ENDM without MACRO");
+		return;
+	}
+	
+	as -> inmacro = 0;
+	
+	// a macro definition counts as a context break for local symbols
+	as -> context = lwasm_next_context(as);
+}
+
+// the current macro will ALWAYS be the first one in the table
+int add_macro_line(asmstate_t *as, char *optr)
+{
+	if (!as -> inmacro)
+		return 0;
+	
+	as -> macros -> lines = lw_realloc(as -> macros -> lines, sizeof(char *) * (as -> macros -> numlines + 1));
+	as -> macros -> lines[as -> macros -> numlines] = lw_strdup(optr);
+	as -> macros -> numlines += 1;
+	return 1;
+}
+
+void macro_add_to_buff(char **buff, int *loc, int *len, char c)
+{
+	if (*loc == *len)
+	{
+		*buff = lw_realloc(*buff, *len + 32);
+		*len += 32;
+	}
+	(*buff)[(*loc)++] = c;
+}
+
+// this is just like a regular operation function
+/*
+macro args are referenced by "\n" where 1 <= n <= 9
+or by "\{n}"; a \ can be included by writing \\
+a comma separates argument but one can be included with "\,"
+whitespace ends argument list but can be included with "\ " or the like
+
+*/
+int expand_macro(asmstate_t *as, line_t *l, char **p, char *opc)
+{
+	int lc;
+	line_t *cl, *nl;
+	int oldcontext;
+	macrotab_t *m;
+
+	char **args = NULL;		// macro arguments
+	int nargs = 0;			// number of arguments
+
+	char *p2, *p3;
+	
+	int bloc, blen;
+	char *linebuff;
+
+	for (m = as -> macros; m; m = m -> next)
+	{
+		if (!strcmp(opc, m -> name))
+			break;
+	}
+	// signal no macro expansion
+	if (!m)
+		return -1;
+	
+	// save current symbol context for after macro expansion
+	oldcontext = as -> context;
+
+	cl = l;
+
+	as -> context = lwasm_next_context(as);
+
+	while (**p && !isspace(**p) && **p != ',')
+	{
+		p2 = *p;
+		while (*p2 && !isspace(*p2) && *p2 != ',')
+		{
+			if (*p2 == '\\')
+			{
+				if (p2[1])
+					p2++;
+			}
+			p2++;
+		}
+
+		// have arg here
+		args = lw_realloc(args, sizeof(char *) * (nargs + 1));
+		args[nargs] = lw_alloc(p2 - *p + 1);
+		args[nargs][p2 - *p] = '\0';
+		memcpy(args[nargs], *p, p2 - *p);
+		*p = p2;
+
+		// now collapse out "\" characters
+		for (p3 = p2 = args[nargs]; *p2; p2++, p3++)
+		{
+			if (*p2 == '\\' && p2[1])
+			{
+				p2++;
+			}
+			*p3 = *p2;
+		}
+		*p3 = '\0';
+		
+		nargs++;
+		if (**p == ',')
+			(*p)++;
+	}
+	
+
+	// now create a string for the macro
+	// and push it into the front of the input stack
+	bloc = blen = 0;
+	linebuff = NULL;
+	
+	for (lc = 0; lc < m -> numlines; lc++)
+	{
+		for (p2 = m -> lines[lc]; *p2; p2++)
+		{
+			if (*p2 == '\\' && isdigit(p2[1]))
+			{
+				int n;
+					
+				p2++;
+				n = *p2 - '0';
+				if (n == 0)
+				{
+					for (p3 = m -> name; *p3; p3++)
+						macro_add_to_buff(&linebuff, &bloc, &blen, *p3);
+					continue;
+				}
+				if (n < 1 || n > nargs)
+					continue;
+				for (p3 = args[n - 1]; *p3; p3++)
+					macro_add_to_buff(&linebuff, &bloc, &blen, *p3);
+				continue;
+			}
+			else if (*p2 == '{')
+			{
+				int n = 0, n2;
+				p2++;
+				while (*p2 && isdigit(*p2))
+				{
+					n2 = *p2 - '0';
+					if (n2 < 0 || n2 > 9)
+						n2 = 0;
+					n = n * 10 + n2;
+					p2++;
+				}
+				if (*p2 == '}')
+					p2++;
+				 
+				if (n == 0)
+				{
+					for (p3 = m -> name; *p3; p3++)
+						macro_add_to_buff(&linebuff, &bloc, &blen, *p3);
+					continue;
+				}
+				if (n < 1 || n > nargs)
+					continue;
+				for (p3 = args[n - 1]; *p3; p3++)
+					macro_add_to_buff(&linebuff, &bloc, &blen, *p3);
+				continue;
+			}
+			else
+			{
+				macro_add_to_buff(&linebuff, &bloc, &blen, *p2);
+			}
+		}
+
+		macro_add_to_buff(&linebuff, &bloc, &blen, '\n');
+		
+	}
+
+	{
+		char ctcbuf[100];
+		char *p;
+		snprintf(ctcbuf, 100, "\001\001SETCONTEXT %d\n", oldcontext);
+		for (p = ctcbuf; *p; p++)
+			macro_add_to_buff(&linebuff, &bloc, &blen, *p);
+	}
+	
+	// push the macro into the front of the stream
+	input_openstring(as, opc, linebuff);
+
+	lw_free(linebuff);
+
+	// clean up
+	if (args)
+	{
+		while (nargs)
+		{
+			lw_free(args[--nargs]);
+		}
+		lw_free(args);
+	}
+
+	// indicate a macro was expanded
+	return 0;	
+}