202105291721 error corrected

preprocess/include/filestack.h

@@ -35,6 +35,8 @@
 */
 
 #define BUFLEN  2048
+#define MAX_UNGET 4
+
 typedef struct _sfilestack {
 	struct _sfilestack * pNext;
 	struct _sfilestack * pLast;
@@ -46,7 +48,9 @@ typedef struct _sfilestack {
 	int filepos;
 	
 	char *buf;
-	int  ungetch;
+	int  ungetchwr;
+	int  ungetchrd;
+	int  ungetchs[MAX_UNGET];
 	int  bufindex;
 	int  buflen;
 	int  isbufonly;
@@ -73,6 +77,23 @@ static void filestack_destroy(filestack * stack)
 	stack->pNext = stack->pLast = stack;
 }
 
+static int filestack_unget(filestack* stack, int ch)
+{
+	stack->ungetchs[stack->ungetchwr] = ch;
+	stack->ungetchwr = (stack->ungetchwr + 1) % MAX_UNGET;
+	return 0;
+}
+
+static int filestack_get_unget(filestack* stack)
+{
+	int ch;
+	if (stack->ungetchrd == stack->ungetchwr)
+		return -1;
+	ch = stack->ungetchs[stack->ungetchrd];
+	stack->ungetchrd = (stack->ungetchrd + 1) % MAX_UNGET;
+	return ch;
+}
+
 static filestack* filestack_push_file(filestack * stack, const char * filename)
 {
 	filestack * pitem;

preprocess/src/verilog_preprocess.c

@@ -32,6 +32,7 @@
 /*
   修改记录：
     202105140816: 根据git的要求增加License
+	202105291720: correct an error on get ch from a filestack
 */
 
 #include "stdio.h"
@@ -642,9 +643,7 @@ static int verilog_preprocess_GetCh(sVerilogPreprocess * pPreprocess)
 		ch = 0;
 		goto returnch;
 	}
-	if (curfile->ungetch != 0) {
-		ch = curfile->ungetch;
-		curfile->ungetch = 0;
+	if ((ch = filestack_get_unget(curfile)) > 0) {
 		goto returnch;
 	} 
 	/* 找到一个有字符的缓冲区 */
@@ -685,6 +684,9 @@ static int verilog_preprocess_GetCh(sVerilogPreprocess * pPreprocess)
 			}
 		}
 		while (curfile->bufindex < curfile->buflen) {
+			if ((ch = filestack_get_unget(curfile)) > 0) {
+				goto returnch;
+			}
 			ch = curfile->buf[curfile->bufindex]; 
 			curfile->bufindex++;
 			/* 滤掉非字符串中的\r字符 */
@@ -744,7 +746,7 @@ static int verilog_preprocess_GetToken(sVerilogPreprocess* pPreprocess, int ch,
 			pPreprocess->tokenstate = TOKEN_NONE;
 			pPreprocess->tokentype = TT_NUMBER;
 			pPreprocess->token[pPreprocess->tokenlen] = 0;
-			pPreprocess->file_stack_top->ungetch = ch;
+			filestack_unget(pPreprocess->file_stack_top, ch);
 			*pch = ' ';
 		}
 	} else if (pPreprocess->tokenstate == TOKEN_IN_SIMIDENT) {
@@ -753,7 +755,7 @@ static int verilog_preprocess_GetToken(sVerilogPreprocess* pPreprocess, int ch,
 			pPreprocess->token[pPreprocess->tokenlen++] = ch;
 			return NEXT_CONTINUE;
 		} else { /* 完成一个SIMIDENT */
-			pPreprocess->file_stack_top->ungetch = ch;
+			filestack_unget(pPreprocess->file_stack_top, ch);
 			*pch = ' ';
 			pPreprocess->tokenstate = TOKEN_NONE;
 			pPreprocess->tokentype = TT_SIMIDENT;
@@ -764,7 +766,7 @@ static int verilog_preprocess_GetToken(sVerilogPreprocess* pPreprocess, int ch,
 			pPreprocess->token[pPreprocess->tokenlen++] = ch;
 			return NEXT_CONTINUE;
 		} else {
-			pPreprocess->file_stack_top->ungetch = ch;
+			filestack_unget(pPreprocess->file_stack_top, ch);
 			*pch = ' ';
 			pPreprocess->token[pPreprocess->tokenlen] = 0;
 			pPreprocess->tokenstate = TOKEN_NONE;
@@ -810,7 +812,7 @@ static int verilog_preprocess_GetToken(sVerilogPreprocess* pPreprocess, int ch,
 			pPreprocess->lastch = ' '; /* 这个*号不能作为结束注释的开始*号 */
 			return NEXT_CONTINUE;
 		} else {
-			pPreprocess->file_stack_top->ungetch = ch;
+			filestack_unget(pPreprocess->file_stack_top, ch);
 			*pch = '/';
 			pPreprocess->tokenstate = TOKEN_NONE;
 			pPreprocess->tokentype = TT_SYMBOL; /*token text is in ch*/
@@ -819,7 +821,7 @@ static int verilog_preprocess_GetToken(sVerilogPreprocess* pPreprocess, int ch,
 		}
 	} else if (pPreprocess->tokenstate == TOKEN_IN_COMMENT) {
 		if ( (ch == '/') && (pPreprocess->lastch == '*') ) {
-			pPreprocess->file_stack_top->ungetch = ' ';
+			filestack_unget(pPreprocess->file_stack_top, ' ');
 			*pch = ' ';
 			pPreprocess->tokenstate = TOKEN_NONE;
 			pPreprocess->tokentype = TT_NONE;
@@ -832,7 +834,7 @@ static int verilog_preprocess_GetToken(sVerilogPreprocess* pPreprocess, int ch,
 		if (ch == '\n') {
 			pPreprocess->tokenstate = TOKEN_NONE;
 			pPreprocess->tokentype = TT_NONE;
-			pPreprocess->file_stack_top->ungetch = '\n';
+			filestack_unget(pPreprocess->file_stack_top, ch);
 			pPreprocess->lastch = ch;
 			return NEXT_CONTINUE;
 		} else {
@@ -844,7 +846,7 @@ static int verilog_preprocess_GetToken(sVerilogPreprocess* pPreprocess, int ch,
 			pPreprocess->tokenstate = TOKEN_NONE;
 			pPreprocess->tokentype = TT_MACRO_TEXT;
 			pPreprocess->token[pPreprocess->tokenlen] = 0;
-			pPreprocess->file_stack_top->ungetch = '\n';
+			filestack_unget(pPreprocess->file_stack_top, ch);
 		} else if (ch == '\\') {
 			pPreprocess->lastch = ch;
 			pPreprocess->tokenstate = TOKEN_IN_MACRO_TEXT_SLASH;
@@ -1478,12 +1480,8 @@ static int verilog_preprocess_state_macro(sVerilogPreprocess * pPreprocess, int
 			pPreprocess->state = STATE_CD_MACRO_PARAM_TEXT;
 			pPreprocess->tokenlen = 0;
 			DLIST_DESTROY(stringitem, &pPreprocess->macro_param_list);
-		} else if (isblank(ch) || (ch == '\n') ) {
-		} else if ( (ch == '/') && (pPreprocess->tokentype != TT_SYMBOL)) {
-			pPreprocess->tokenstate = TOKEN_COMMENT_START;
-			pPreprocess->lastch = '/';
 		} else {
-			pPreprocess->file_stack_top->ungetch = ch;
+			filestack_unget(pPreprocess->file_stack_top, ch);
 			verilog_preprocess_preprocess_PreAction(pPreprocess, PA_MACRO, pPreprocess->macro_name, "");
 			pPreprocess->state = STATE_INITIAL;
 			pPreprocess->tokenstate = TOKEN_NONE;
@@ -1491,7 +1489,6 @@ static int verilog_preprocess_state_macro(sVerilogPreprocess * pPreprocess, int
 		}
 		return NEXT_CONTINUE;
 	} else if (pPreprocess->state == STATE_CD_MACRO_PARAM_TEXT) {
-		pPreprocess->file_stack_top->ungetch = ch;
 		ch = verilog_preprocess_GetMacroParamText(pPreprocess);
 		pPreprocess->token[pPreprocess->tokenlen] = 0;
 		stringlistaddstring(&pPreprocess->macro_param_list, pPreprocess->token);