From: erg <devnull@localhost>
Date: Thu, 12 Oct 2006 23:11:49 +0000 (+0000)
Subject: Fix line folding bug where previous fgets ends in '\\' and next
X-Git-Tag: LAST_LIBGRAPH~32^2~5830
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=c319a93f35cb5a66bf4a3469b18a99c1c11b4bef;p=graphviz

Fix line folding bug where previous fgets ends in '\\' and next
fgets returns a single '\n'. The code needs to handle this case,
and back up the buffer appropriately.
---

diff --git a/lib/graph/lexer.c b/lib/graph/lexer.c
index ffe734e79..f86afd158 100644
--- a/lib/graph/lexer.c
+++ b/lib/graph/lexer.c
@@ -249,12 +249,18 @@ static char *lex_gets(void)
 		continue;
 	    }
 	    Line_number++;
-	    if ((len > 1) && (clp[len - 2] == '\\')) {	/* escaped newline */
+		/* Note it is possible len == 1 and last character in
+		 * previous read was '\\'
+		 * It is also possible to have curlen=0, and read in
+		 * "\\\n". 
+		 */
+	    if (clp[len - 2] == '\\') {	/* escaped newline */
 		len = len - 2;
 		clp[len] = '\0';
 	    }
 	}
 	curlen += len;
+	/* the following test relies on having AG.linebuf[0] == '\0' */
     } while (clp[len - 1] != '\n');
 
     if (curlen > 0)