From 4b2ae689ed8a6e7597382c87f817f95d556a54c2 Mon Sep 17 00:00:00 2001
From: Randy Heit <rheit@zdoom.fake>
Date: Mon, 23 Jan 2012 02:47:51 +0000
Subject: [PATCH] - Added modulus to FParseContext/xlat. - Fixed: Division of
 tag arguments for xlat was in the wrong order.

SVN r3344 (trunk)
---
 src/p_xlat.cpp         | 15 ++++++++-------
 src/parsecontext.cpp   |  1 +
 src/parsecontext.h     |  2 ++
 src/xlat/xlat.h        |  1 +
 src/xlat/xlat_parser.y | 10 ++++++++++
 5 files changed, 22 insertions(+), 7 deletions(-)

diff --git a/src/p_xlat.cpp b/src/p_xlat.cpp
index 28792ff7a..07828ac50 100644
--- a/src/p_xlat.cpp
+++ b/src/p_xlat.cpp
@@ -137,13 +137,14 @@ void P_TranslateLineDef (line_t *ld, maplinedef_t *mld)
 			int tagop = (linetrans->flags >> (LINETRANS_TAGSHIFT + t*TAGOP_NUMBITS)) & TAGOP_MASK;
 			switch (tagop)
 			{
-			case TAGOP_None:	default:				break;
-			case TAGOP_Add:		ld->args[t] += tag;		break;
-			case TAGOP_Mul:		ld->args[t] *= tag;		break;
-			case TAGOP_Div:		ld->args[t] /= tag;		break;
-			case TAGOP_And:		ld->args[t] &= tag;		break;
-			case TAGOP_Or:		ld->args[t] |= tag;		break;
-			case TAGOP_Xor:		ld->args[t] ^= tag;		break;
+			case TAGOP_None:	default:							break;
+			case TAGOP_Add:		ld->args[t] += tag;					break;
+			case TAGOP_Mul:		ld->args[t] *= tag;					break;
+			case TAGOP_Div:		ld->args[t] = tag / ld->args[t];	break;
+			case TAGOP_Mod:		ld->args[t] = tag % ld->args[t];	break;
+			case TAGOP_And:		ld->args[t] &= tag;					break;
+			case TAGOP_Or:		ld->args[t] |= tag;					break;
+			case TAGOP_Xor:		ld->args[t] ^= tag;					break;
 			}
 		}
 
diff --git a/src/parsecontext.cpp b/src/parsecontext.cpp
index 5b764d954..6fa36b2a8 100644
--- a/src/parsecontext.cpp
+++ b/src/parsecontext.cpp
@@ -267,6 +267,7 @@ loop:
 	case '-': return TokenTrans[MINUS];
 	case '+': return TokenTrans[PLUS];
 	case '*': return TokenTrans[MULTIPLY];
+	case '%': return TokenTrans[MODULUS];
 	case '(': return TokenTrans[LPAREN];
 	case ')': return TokenTrans[RPAREN];
 	case ',': return TokenTrans[COMMA];
diff --git a/src/parsecontext.h b/src/parsecontext.h
index 020fc7e03..bafeaa888 100644
--- a/src/parsecontext.h
+++ b/src/parsecontext.h
@@ -47,6 +47,7 @@ enum
 	 PLUS     ,
 	 MULTIPLY ,
 	 DIVIDE   ,
+	 MODULUS  ,
 	 NUM      ,
 	 FLOATVAL ,
 	 LPAREN   ,
@@ -78,6 +79,7 @@ enum
 	prefix##PLUS, \
 	prefix##MULTIPLY, \
 	prefix##DIVIDE, \
+	prefix##MODULUS, \
 	prefix##NUM, \
 	prefix##FLOATVAL, \
 	prefix##LPAREN, \
diff --git a/src/xlat/xlat.h b/src/xlat/xlat.h
index 0653d4ab6..765b9fd78 100644
--- a/src/xlat/xlat.h
+++ b/src/xlat/xlat.h
@@ -10,6 +10,7 @@ enum ELineTransTagOp
 	TAGOP_Add,
 	TAGOP_Mul,
 	TAGOP_Div,
+	TAGOP_Mod,
 	TAGOP_And,
 	TAGOP_Or,
 	TAGOP_Xor,
diff --git a/src/xlat/xlat_parser.y b/src/xlat/xlat_parser.y
index 1f14409c4..0fc702f74 100644
--- a/src/xlat/xlat_parser.y
+++ b/src/xlat/xlat_parser.y
@@ -36,6 +36,7 @@ exp(A) ::= exp(B) PLUS exp(C).		{ A = B + C; }
 exp(A) ::= exp(B) MINUS exp(C).		{ A = B - C; }
 exp(A) ::= exp(B) MULTIPLY exp(C).	{ A = B * C; }
 exp(A) ::= exp(B) DIVIDE exp(C).	{ if (C != 0) A = B / C; else context->PrintError("Division by zero"); }
+exp(A) ::= exp(B) MODULUS exp(C).	{ if (C != 0) A = B % C; else context->PrintError("Division by zero"); }
 exp(A) ::= exp(B) OR exp(C).		{ A = B | C; }
 exp(A) ::= exp(B) AND exp(C).		{ A = B & C; }
 exp(A) ::= exp(B) XOR exp(C).		{ A = B ^ C; }
@@ -135,6 +136,15 @@ special_arg(Z) ::= TAG DIVIDE exp(A).
 		context->PrintError("Division by zero");
 	}
 }
+special_arg(Z) ::= TAG MODULUS exp(A).
+{
+	Z.arg = A;
+	Z.tagop = TAGOP_Mod;
+	if (A == 0)
+	{
+		context->PrintError("Division by zero");
+	}
+}
 special_arg(Z) ::= TAG OR exp(A).
 {
 	Z.arg = A;