tree-wide: drop 'This file is part of systemd' blurb

[thirdparty/systemd.git] / src / basic / strxcpyx.c

diff --git a/src/basic/strxcpyx.c b/src/basic/strxcpyx.c
index 6542c0abf54d77dc4c363db0759a028a11ef95f4..3fdc72563639bc74bd55abeb6dbed604239c828c 100644 (file)
--- a/src/basic/strxcpyx.c
+++ b/src/basic/strxcpyx.c
@@ -1,37 +1,34 @@
-/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
-
+/* SPDX-License-Identifier: LGPL-2.1+ */
 /***
-  This file is part of systemd.
-
   Copyright 2013 Kay Sievers
-
-  systemd is free software; you can redistribute it and/or modify it
-  under the terms of the GNU Lesser General Public License as published by
-  the Free Software Foundation; either version 2.1 of the License, or
-  (at your option) any later version.
-
-  systemd is distributed in the hope that it will be useful, but
-  WITHOUT ANY WARRANTY; without even the implied warranty of
-  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
-  Lesser General Public License for more details.
-
-  You should have received a copy of the GNU Lesser General Public License
-  along with systemd; If not, see <http://www.gnu.org/licenses/>.
 ***/
 
 /*
  * Concatenates/copies strings. In any case, terminates in all cases
- * with '\0' * and moves the @dest pointer forward to the added '\0'.
- * Returns the * remaining size, and 0 if the string was truncated.
+ * with '\0' and moves the @dest pointer forward to the added '\0'.
+ * Returns the remaining size, and 0 if the string was truncated.
+ *
+ * Due to the intended usage, these helpers silently noop invocations
+ * having zero size.  This is technically an exception to the above
+ * statement "terminates in all cases".  It's unexpected for such calls to
+ * occur outside of a loop where this is the preferred behavior.
  */
 
+#include <stdarg.h>
 #include <stdio.h>
 #include <string.h>
+
 #include "strxcpyx.h"
 
 size_t strpcpy(char **dest, size_t size, const char *src) {
         size_t len;
 
+        assert(dest);
+        assert(src);
+
+        if (size == 0)
+                return 0;
+
         len = strlen(src);
         if (len >= size) {
                 if (size > 1)
@@ -51,23 +48,30 @@ size_t strpcpyf(char **dest, size_t size, const char *src, ...) {
         va_list va;
         int i;
 
+        assert(dest);
+        assert(src);
+
+        if (size == 0)
+                return 0;
+
         va_start(va, src);
         i = vsnprintf(*dest, size, src, va);
         if (i < (int)size) {
                 *dest += i;
                 size -= i;
         } else {
-                *dest += size;
                 size = 0;
         }
         va_end(va);
-        *dest[0] = '\0';
         return size;
 }
 
 size_t strpcpyl(char **dest, size_t size, const char *src, ...) {
         va_list va;
 
+        assert(dest);
+        assert(src);
+
         va_start(va, src);
         do {
                 size = strpcpy(dest, size, src);
@@ -80,6 +84,9 @@ size_t strpcpyl(char **dest, size_t size, const char *src, ...) {
 size_t strscpy(char *dest, size_t size, const char *src) {
         char *s;
 
+        assert(dest);
+        assert(src);
+
         s = dest;
         return strpcpy(&s, size, src);
 }
@@ -88,6 +95,9 @@ size_t strscpyl(char *dest, size_t size, const char *src, ...) {
         va_list va;
         char *s;
 
+        assert(dest);
+        assert(src);
+
         va_start(va, src);
         s = dest;
         do {