shithub: scc

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Detect EOF condition and don't enter in infinite loops

Once we found the EOF condition in the lowest level we should
not try to read more characters, because it made impossible
to finish the exection when input is reading from stdin.

--- a/cc1/cc1.h

+++ b/cc1/cc1.h

@@ -272,7 +272,6 @@

 extern void setfname(char *name);

 extern void setfline(unsigned short line);

 extern bool addinput(char *fname);

-extern void delinput(void);

 extern void setnamespace(int ns);

 extern void setsafe(int type);

 #define accept(t) ((yytoken == (t)) ? next() : 0)

--- a/cc1/lex.c

+++ b/cc1/lex.c

@@ -23,14 +23,15 @@

 	struct input *next;

 };

-static unsigned lex_ns = NS_IDEN;

-

 unsigned yytoken;

 struct yystype yylval;

 char yytext[IDENTSIZ + 1];

 unsigned short yylen;

+

+static unsigned lex_ns = NS_IDEN;

 static int safe;

 static Input *input;

+static int eof;

 bool

 addinput(char *fname)

@@ -71,13 +72,14 @@

 	Input *ip = input;

 	FILE *fp = ip->fp;

+	if (!ip->next)

+		eof = 1;

 	if (fp) {

 		if (fclose(fp))

 			die("error reading from input file '%s'", ip->fname);

-		if (!ip->next)

+		if (eof)

 			return;

-		if (ip->fp != stdin)

-			free(ip->fname);

+		free(ip->fname);

 	}

 	input = ip->next;

 	free(ip->line);

@@ -113,9 +115,15 @@

 readchar(void)

 {

 	int c;

-	FILE *fp = input->fp;

-

+	FILE *fp;

+	

 repeat:

+	while (feof(input->fp) && !eof)

+		delinput();

+	if (eof)

+		return EOF;

+	fp = input->fp;

+

 	if ((c = getc(fp)) == '\\') {

 		if ((c = getc(fp)) == '\n')

 			goto repeat;

@@ -122,6 +130,8 @@

 		ungetc(c, fp);

 		c = '\\';

 	}

+	if (c == '\n' && ++input->nline == 0)

+		die("input file '%s' too long", getfname());

 	return c;

 }

@@ -128,7 +138,7 @@

 static void

 readline(void)

 {

-	static int comment, commentline;

+	int comment = 0, commentline = 0;

 	char *bp, *lim;

 	int c;

@@ -156,8 +166,8 @@

 		if (c == '\n')

 			break;

 		if (bp == lim)

-			die("line %d too big in file '%s'",

-			    input->nline, input->fname);

+			die("line %u too big in file '%s'",

+			    getfline(), getfname());

 		if (c == '/') {

 			if ((c = readchar()) == '*') {

 				comment = 1;

@@ -171,7 +181,6 @@

 		}

 		*bp++ = c;

 	}

-	ungetc(c, input->fp);

 	*bp = '\0';

 }

@@ -178,33 +187,22 @@

 static bool

 fill(void)

 {

-	int c;

 	char *p;

-	FILE *fp;

+	int c;

 repeat:

-	if (!input)

+	if (eof)

 		return 0;

 	if (input->begin && *input->begin != '\0')

 		return 1;

-

-	fp = input->fp;

 	if (!input->line)

 		input->line = xmalloc(INPUTSIZ);

-

-	while ((c = getc(fp)) != EOF && (c == '\n')) {

-		if (++input->nline == 0)

-			die("input file '%s' too long", input->fname);

-	}

-	if (c == EOF) {

-		delinput();

-		goto repeat;

-	}

-	ungetc(c, fp);

 	readline();

+	if (*input->line == '\0')

+		goto repeat;

 	if ((p = preprocessor(input->line)) == NULL)

 		goto repeat;

-	input->begin = input->p = p;

+	input->p = input->begin = p;

 	return 1;

 }

@@ -377,8 +375,8 @@

 		input->begin = input->p;

 		if (isspace((c = *input->p))) {

 			++input->p;

-		} else if (c == '\0') {

-			fill();

+		} else if (c == '\0' && fill()) {

+			continue;

 		} else if (c == '"') {

 			goto repeat;

 		} else {

@@ -513,12 +511,15 @@

 {

 	char c;

-	if (!fill())

+repeat:

+	if (!fill()) {

+		strcpy(yytext, "<EOF>");

 		return yytoken = EOFTOK;

-

+	}

 	while (isspace(*input->begin))

 		++input->begin;

-	c = *(input->p = input->begin);

+	if ((c = *(input->p = input->begin)) == '\0')

+		goto repeat;

 	if (isalpha(c) || c == '_') {

 		yytoken = iden();

@@ -553,16 +554,13 @@

 {

 	int c;

-	/* FIX: It will break all the error messages */

 repeat:

 	if (!fill())

 		return EOFTOK;

 	while (isspace(c = *input->begin))

 		++input->begin;

-	if (c == '\0') {

-		fill();

+	if (c == '\0')

 		goto repeat;

-	}

 	return c;

 }