From: rousskov <>
Date: Fri, 28 Aug 1998 04:00:07 +0000 (+0000)
Subject: - one IRIX an unsigned size_t creates problems when we do (len-1) in snprintf
X-Git-Tag: SQUID_3_0_PRE1~2780
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=ab8ec2d82f3b38117ade0bb2524df7b6bd3a379d;p=thirdparty%2Fsquid.git

- one IRIX an unsigned size_t creates problems when we do (len-1) in snprintf
  fixed by cheking that len is positive before subtracting 1.
- return value was sometimes uninitialized when calling snprintf
---

diff --git a/lib/snprintf.c b/lib/snprintf.c
index c3c31f3cff..d7edcbe1f0 100644
--- a/lib/snprintf.c
+++ b/lib/snprintf.c
@@ -880,6 +880,8 @@ format_converter(register buffy * odp, const char *fmt,
 
 /*
  * This is the general purpose conversion function.
+ * Must be called with len >= 0, but we cannot assert() that
+ * because size_t is unsigned on some platforms
  */
 static void
 strx_printv(int *ccp, char *buf, size_t len, const char *format,
@@ -888,14 +890,6 @@ strx_printv(int *ccp, char *buf, size_t len, const char *format,
     buffy od;
     int cc;
 
-    /*
-     * If someone calls snprintf(buf, 0, ...), then len == -1 here.
-     * Previously this code would assume an "unlimited" buffer size,
-     * thereby emulating sprintf().  Now we silently return and hope
-     * the caller doesn't expect us to terminate the buffer!
-     */
-    if (len < 0)
-	return;
     /*
      * First initialize the descriptor
      * Notice that if no length is given, we initialize buf_end to the
@@ -925,9 +919,8 @@ snprintf(char *buf, size_t len, const char *format,...)
 {
     int cc;
     va_list ap;
-    assert(len >= 0);
     va_start(ap, format);
-    strx_printv(&cc, buf, (len - 1), format, ap);
+    cc = vsnprintf(buf, len, format, ap);
     va_end(ap);
     return (cc);
 }
@@ -938,9 +931,16 @@ int
 vsnprintf(char *buf, size_t len, const char *format,
     va_list ap)
 {
-    int cc;
+    int cc = 0;
     assert(len >= 0);
-    strx_printv(&cc, buf, (len - 1), format, ap);
+    /*
+     * If someone calls snprintf(buf, 0, ...), then len becomes "(size_t)-1" in
+     * strx_printhv.  Previously this code would assume an "unlimited" buffer
+     * size, thereby emulating sprintf().  Now we silently do nothing and hope
+     * the caller doesn't expect us to terminate the buffer!
+     */
+    if (len > 0)
+	strx_printv(&cc, buf, (len - 1), format, ap);
     return (cc);
 }
 #endif