From: Jeremy Hylton <jeremy@alum.mit.edu>
Date: Wed, 28 Nov 2001 21:44:53 +0000 (+0000)
Subject: Use PyOS_vsnprintf() and check its return value.
X-Git-Tag: v2.2.1c1~661
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=5d3d134d560d24a9e6b9d65dd814542605c0b152;p=thirdparty%2FPython%2Fcpython.git

Use PyOS_vsnprintf() and check its return value.

If it returns -1 (which indicates overflow on old Linux platforms and
perhaps on Windows) or size greater than buffer, write a message
indicating that the previous message was truncated.
---

diff --git a/Python/sysmodule.c b/Python/sysmodule.c
index 1ca69b4da7e9..8b27b37b76b7 100644
--- a/Python/sysmodule.c
+++ b/Python/sysmodule.c
@@ -1023,12 +1023,19 @@ mywrite(char *name, FILE *fp, const char *format, va_list va)
 		vfprintf(fp, format, va);
 	else {
 		char buffer[1001];
-		if (vsprintf(buffer, format, va) >= sizeof(buffer))
-		    Py_FatalError("PySys_WriteStdout/err: buffer overrun");
+		int written = PyOS_vsnprintf(buffer, sizeof(buffer), 
+					     format, va);
 		if (PyFile_WriteString(buffer, file) != 0) {
 			PyErr_Clear();
 			fputs(buffer, fp);
 		}
+		if (written == -1 || written > sizeof(buffer)) {
+			const char *truncated = "... truncated";
+			if (PyFile_WriteString(truncated, file) != 0) {
+				PyErr_Clear();
+				fputs(truncated, fp);
+			}
+		}
 	}
 	PyErr_Restore(error_type, error_value, error_traceback);
 }