From: Arran Cudbard-Bell <a.cudbardb@freeradius.org>
Date: Wed, 15 Jul 2015 03:36:16 +0000 (-0400)
Subject: Alternate where we write errors in fr_strerror_printf to allow error messages to... 
X-Git-Tag: release_3_0_10~335
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=a6d3793cb93444b4ced344c8c3dfa5cbbcde4f54;p=thirdparty%2Ffreeradius-server.git

Alternate where we write errors in fr_strerror_printf to allow error messages to be appended to
---

diff --git a/src/lib/log.c b/src/lib/log.c
index b0a978e5461..227b3a42d4d 100644
--- a/src/lib/log.c
+++ b/src/lib/log.c
@@ -65,7 +65,7 @@ void fr_strerror_printf(char const *fmt, ...)
 		/*
 		 *	malloc is thread safe, talloc is not
 		 */
-		buffer = malloc(sizeof(char) * (FR_STRERROR_BUFSIZE + 1));	/* One byte extra for status */
+		buffer = calloc((FR_STRERROR_BUFSIZE * 2) + 1, sizeof(char));	/* One byte extra for status */
 		if (!buffer) {
 			fr_perror("Failed allocating memory for libradius error buffer");
 			return;
@@ -83,13 +83,26 @@ void fr_strerror_printf(char const *fmt, ...)
 	 *	NULL has a special meaning, setting the new byte to false.
 	 */
 	if (!fmt) {
-		buffer[FR_STRERROR_BUFSIZE] = '\0';
+		buffer[FR_STRERROR_BUFSIZE * 2] = '\0';
 		return;
 	}
 
 	va_start(ap, fmt);
-	vsnprintf(buffer, FR_STRERROR_BUFSIZE, fmt, ap);
-	buffer[FR_STRERROR_BUFSIZE] = '\1';			/* Flip the 'new' byte to true */
+	/*
+	 *	Alternate where we write the message, so we can do:
+	 *	fr_strerror_printf("Additional error: %s", fr_strerror());
+	 */
+	switch (buffer[FR_STRERROR_BUFSIZE * 2]) {
+	default:
+		vsnprintf(buffer + FR_STRERROR_BUFSIZE, FR_STRERROR_BUFSIZE, fmt, ap);
+		buffer[FR_STRERROR_BUFSIZE * 2] = '\2';			/* Flip the 'new' byte to true */
+		break;
+
+	case '\2':
+		vsnprintf(buffer, FR_STRERROR_BUFSIZE, fmt, ap);
+		buffer[FR_STRERROR_BUFSIZE * 2] = '\1';			/* Flip the 'new' byte to true */
+		break;
+	}
 	va_end(ap);
 }
 
@@ -104,12 +117,20 @@ char const *fr_strerror(void)
 	char *buffer;
 
 	buffer = fr_thread_local_get(fr_strerror_buffer);
-	if (buffer && (buffer[FR_STRERROR_BUFSIZE] != '\0')) {
-		buffer[FR_STRERROR_BUFSIZE] = '\0';		/* Flip the 'new' byte to false */
+	if (!buffer) return "";
+
+	switch (buffer[FR_STRERROR_BUFSIZE * 2]) {
+	default:
+		return "";
+
+	case '\1':
+		buffer[FR_STRERROR_BUFSIZE * 2] = '\0';		/* Flip the 'new' byte to false */
 		return buffer;
-	}
 
-	return "";
+	case '\2':
+		buffer[FR_STRERROR_BUFSIZE * 2] = '\0';		/* Flip the 'new' byte to false */
+		return buffer + FR_STRERROR_BUFSIZE;
+	}
 }
 
 /** Guaranteed to be thread-safe version of strerror