Cope with versions of vsnprintf() written by people who

tglsfdc · tglsfdc · commit b1134e369f8b · 1999-09-08T16:31:38.000Z
don't read man pages...
diff --git a/src/backend/lib/stringinfo.c b/src/backend/lib/stringinfo.c
@@ -8,7 +8,7 @@
  *
  * Copyright (c) 1994, Regents of the University of California
  *
- *	  $Id: stringinfo.c,v 1.21 1999/08/31 01:28:25 tgl Exp $
+ *	  $Id: stringinfo.c,v 1.22 1999/09/08 16:31:38 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -121,7 +121,12 @@ appendStringInfo(StringInfo str, const char *fmt,...)
 			nprinted = vsnprintf(str->data + str->len, avail,
 								 fmt, args);
 			va_end(args);
-			if (nprinted < avail-1)
+			/*
+			 * Note: some versions of vsnprintf return the number of chars
+			 * actually stored, but at least one returns -1 on failure.
+			 * Be conservative about believing whether the print worked.
+			 */
+			if (nprinted >= 0 && nprinted < avail-1)
 			{
 				/* Success.  Note nprinted does not include trailing null. */
 				str->len += nprinted;

Original file line number	Diff line number	Diff line change
`@@ -8,7 +8,7 @@`
`8`	`8`	`*`
`9`	`9`	`* Copyright (c) 1994, Regents of the University of California`
`10`	`10`	`*`
`11`		`- * $Id: stringinfo.c,v 1.21 1999/08/31 01:28:25 tgl Exp $`
	`11`	`+ * $Id: stringinfo.c,v 1.22 1999/09/08 16:31:38 tgl Exp $`
`12`	`12`	`*`
`13`	`13`	`*-------------------------------------------------------------------------`
`14`	`14`	`*/`
`@@ -121,7 +121,12 @@ appendStringInfo(StringInfo str, const char *fmt,...)`
`121`	`121`	`nprinted = vsnprintf(str->data + str->len, avail,`
`122`	`122`	`fmt, args);`
`123`	`123`	`va_end(args);`
`124`		`- if (nprinted < avail-1)`
	`124`	`+ /*`
	`125`	`+ * Note: some versions of vsnprintf return the number of chars`
	`126`	`+ * actually stored, but at least one returns -1 on failure.`
	`127`	`+ * Be conservative about believing whether the print worked.`
	`128`	`+ */`
	`129`	`+ if (nprinted >= 0 && nprinted < avail-1)`
`125`	`130`	`{`
`126`	`131`	`/* Success. Note nprinted does not include trailing null. */`
`127`	`132`	`str->len += nprinted;`