--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/lwasm/section.c	Wed Jan 19 22:27:17 2011 -0700
@@ -0,0 +1,351 @@
+/*
+section.c
+
+Copyright © 2010 William Astle
+
+This file is part of LWTOOLS.
+
+LWTOOLS 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/>.
+*/
+
+#include <string.h>
+
+#include <lw_string.h>
+#include <lw_alloc.h>
+
+#include "lwasm.h"
+#include "instab.h"
+
+PARSEFUNC(pseudo_parse_section)
+{
+	char *p2;
+	char *sn;
+	char *opts = NULL;
+	sectiontab_t *s;
+
+	if (as -> output_format != OUTPUT_OBJ)
+	{
+		lwasm_register_error(as, l, "Cannot use sections unless using the object target");
+		return;
+	}
+	
+	if (!**p)
+	{
+		lwasm_register_error(as, l, "Need section name");
+		return;
+	}
+
+	l -> len = 0;
+
+	if (as -> csect)
+	{
+		lw_expr_destroy(as -> csect -> offset);
+		as -> csect -> offset = lw_expr_copy(l -> addr);
+		as -> csect = NULL;
+	}
+	
+	for (p2 = *p; *p2 && *p2 != ',' && !isspace(*p2); p2++)
+		/* do nothing */ ;
+	
+	sn = lw_strndup(*p, p2 - *p);
+	*p = p2;
+	
+	if (**p == ',')
+	{
+		// have opts
+		(*p)++;
+		
+		for (p2 = *p; *p2 && !isspace(*p2); p2++)
+			/* do nothing */ ;
+		
+		opts = lw_strndup(*p, p2 - *p);
+		*p = p2;
+	}
+
+	for (s = as -> sections; s; s = s -> next)
+	{
+		if (!strcmp(s -> name, sn))
+			break;
+	}
+	if (s && opts)
+	{
+		lwasm_register_warning(as, l, "Section flags can only be specified the first time; ignoring duplicate definition");
+	}
+	if (!s)
+	{
+		// create section data structure
+		s = lw_alloc(sizeof(sectiontab_t));
+		s -> oblen = 0;
+		s -> obsize = 0;
+		s -> obytes = NULL;
+		s -> name = lw_strdup(sn);
+		s -> offset = lw_expr_build(lw_expr_type_special, lwasm_expr_secbase, s);
+		s -> flags = section_flag_none;
+		s -> reloctab = NULL;
+		if (!strcasecmp(sn, "bss") || !strcasecmp(sn, ".bss"))
+		{
+			s -> flags |= section_flag_bss;
+		}
+		// parse options
+		if (opts)
+		{
+			// only one option ("bss" or "!bss")
+			if (!strcasecmp(opts, "bss"))
+			{
+				s -> flags |= section_flag_bss;
+			}
+			else if (!strcasecmp(opts, "!bss"))
+			{
+				s -> flags &= ~section_flag_bss;
+			}
+			else
+			{
+				lwasm_register_error(as, l, "Unrecognized section flag");
+				lw_free(sn);
+				lw_free(opts);
+				lw_free(s -> name);
+				lw_expr_destroy(s -> offset);
+				lw_free(s);
+				return;
+			}
+		}
+		s -> next = as -> sections;
+		as -> sections = s;
+	}
+	
+	lw_expr_destroy(l -> addr);
+	l -> addr = lw_expr_copy(s -> offset);
+	
+	as -> csect = s;
+	as -> context = lwasm_next_context(as);
+
+	l -> len = 0;
+	
+	lw_free(opts);
+	lw_free(sn);
+}
+
+PARSEFUNC(pseudo_parse_endsection)
+{
+	if (as -> output_format != OUTPUT_OBJ)
+	{
+		lwasm_register_error(as, l, "Cannot use sections unless using the object target");
+		return;
+	}
+
+	l -> len = 0;
+
+	if (!(as -> csect))
+	{
+		lwasm_register_error(as, l, "ENDSECTION without SECTION");
+		return;
+	}
+
+	// save offset in case another instance of the section appears	
+	lw_expr_destroy(as -> csect -> offset);
+	as -> csect -> offset = l -> addr;
+	
+	// reset address to 0
+	l -> addr = lw_expr_build(lw_expr_type_int, 0);
+	as -> csect = NULL;
+	
+	// end of section is a context break
+	as -> context = lwasm_next_context(as);
+
+	skip_operand(p);
+}
+
+PARSEFUNC(pseudo_parse_export)
+{
+	int after = 0;
+	char *sym = NULL;
+	exportlist_t *e;
+	
+	if (as -> output_format != OUTPUT_OBJ)
+	{
+		lwasm_register_error(as, l, "EXPORT only supported for object target");
+		return;
+	}
+
+	l -> len = 0;
+	
+	if (l -> sym)
+	{
+		sym = lw_strdup(l -> sym);
+		l -> symset = 1;
+	}
+	
+	if (l -> sym)
+	{
+		skip_operand(p);
+	}
+
+again:
+	if (after || !sym)
+	{
+		char *p2;
+		
+		after = 1;
+		for (p2 = *p; *p2 && *p2 != ',' && !isspace(*p2); p2++)
+			/* do nothing */ ;
+		
+		sym = lw_strndup(*p, p2 - *p);
+		*p = p2;
+	}
+	if (!sym)
+	{
+		lwasm_register_error(as, l, "No symbol for EXPORT");
+		return;
+	}
+	
+	// add the symbol to the "export" list (which will be resolved
+	// after the parse pass is complete
+	e = lw_alloc(sizeof(exportlist_t));
+	e -> next = as -> exportlist;
+	e -> symbol = lw_strdup(sym);
+	e -> line = l;
+	e -> se = NULL;
+	as -> exportlist = e;
+	lw_free(sym);
+	
+	if (after && **p == ',')
+	{
+		(*p)++;
+		for (; **p && isspace(**p); (*p)++)
+			/* do nothing */ ;
+		goto again;
+	}
+}
+
+PARSEFUNC(pseudo_parse_extern)
+{
+	int after = 0;
+	char *sym = NULL;
+	importlist_t *e;
+	
+	if (as -> output_format != OUTPUT_OBJ)
+	{
+		lwasm_register_error(as, l, "IMPORT only supported for object target");
+		return;
+	}
+	
+	l -> len = 0;
+	
+	if (l -> sym)
+	{
+		sym = lw_strdup(l -> sym);
+		l -> symset = 1;
+	}
+	
+	if (l -> sym)
+	{
+		skip_operand(p);
+	}
+
+again:
+	if (after || !sym)
+	{
+		char *p2;
+		
+		after = 1;
+		for (p2 = *p; *p2 && *p2 != ',' && !isspace(*p2); p2++)
+			/* do nothing */ ;
+		
+		sym = lw_strndup(*p, p2 - *p);
+		*p = p2;
+	}
+	if (!sym)
+	{
+		lwasm_register_error(as, l, "No symbol for IMPORT");
+		return;
+	}
+	
+	// add the symbol to the "export" list (which will be resolved
+	// after the parse pass is complete
+	e = lw_alloc(sizeof(importlist_t));
+	e -> next = as -> importlist;
+	e -> symbol = lw_strdup(sym);
+	as -> importlist = e;
+	lw_free(sym);
+	
+	if (after && **p == ',')
+	{
+		(*p)++;
+		for (; **p && isspace(**p); (*p)++)
+			/* do nothing */ ;
+		goto again;
+	}
+}
+
+PARSEFUNC(pseudo_parse_extdep)
+{
+	int after = 0;
+	char *sym = NULL;
+	importlist_t *e;
+	
+	if (as -> output_format != OUTPUT_OBJ)
+	{
+		lwasm_register_error(as, l, "EXTDEP only supported for object target");
+		return;
+	}
+	
+	if (!as -> csect)
+	{
+		lwasm_register_error(as, l, "EXTDEP must be within a section");
+		return;
+	}
+	
+	l -> len = 0;
+	
+	if (l -> sym)
+		sym = lw_strdup(l -> sym);
+	
+	if (l -> sym)
+	{
+		skip_operand(p);
+	}
+
+again:
+	if (after || !sym)
+	{
+		char *p2;
+		
+		after = 1;
+		for (p2 = *p; *p2 && *p2 != ',' && !isspace(*p2); p2++)
+			/* do nothing */ ;
+		
+		sym = lw_strndup(*p, p2 - *p);
+	}
+	if (!sym)
+	{
+		lwasm_register_error(as, l, "No symbol for EXTDEP");
+		return;
+	}
+	
+	// create a zero-width dependency
+	{
+		lw_expr_t e;
+		e = lw_expr_build(lw_expr_type_int, 0);
+		lwasm_emitexpr(l, e, 0);
+		lw_expr_destroy(e);
+	}
+	
+	if (after && **p == ',')
+	{
+		(*p)++;
+		for (; **p && isspace(**p); (*p)++)
+			/* do nothing */ ;
+		goto again;
+	}
+}