Add an internal function for appending a character to a dynamically

allocated string, expanding the string if necessary.


git-svn-id: svn+ssh://svn.openpam.org/svn/openpam/trunk@528 185d5e19-27fe-0310-9dcf-9bff6b9f3609

lib/Makefile.am

@@ -31,6 +31,7 @@ libpam_la_SOURCES = \
 	openpam_restore_cred.c \
 	openpam_set_option.c \
 	openpam_static.c \
+	openpam_straddch.c \
 	openpam_subst.c \
 	openpam_ttyconv.c \
 	pam_acct_mgmt.c \

lib/openpam_impl.h

@@ -143,6 +143,7 @@ struct pam_saved_cred {
 /*
  * Internal functions
  */
+int		 openpam_straddch(char **, size_t *, size_t *, char);
 int		 openpam_configure(pam_handle_t *, const char *);
 int		 openpam_dispatch(pam_handle_t *, int, int);
 int		 openpam_findenv(pam_handle_t *, const char *, size_t);

lib/openpam_straddch.c

@@ -0,0 +1,75 @@
+/*-
+ * Copyright (c) 2012 Dag-Erling Smørgrav
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer
+ *    in this position and unchanged.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ * $Id$
+ */
+
+#ifdef HAVE_CONFIG_H
+# include "config.h"
+#endif
+
+#include <stdlib.h>
+
+#include <security/pam_appl.h>
+#include "openpam_impl.h"
+
+/*
+ * OpenPAM extension
+ *
+ * Add a character to a string, expanding the buffer if needed.
+ */
+
+int
+openpam_straddch(char **str, size_t *size, size_t *len, char ch)
+{
+	char *tmp;
+
+	if (*str == NULL) {
+		/* initial allocation */
+		if ((*str = malloc(*size = 32)) == NULL) {
+			openpam_log(PAM_LOG_ERROR, "malloc(): %m");
+			return (-1);
+		}
+		*len = 0;
+	} else if (*len >= *size - 1) {
+		/* additional space required */
+		if ((tmp = realloc(*str, *size *= 2)) == NULL) {
+			openpam_log(PAM_LOG_ERROR, "realloc(): %m");
+			free(*str);
+			*str = NULL;
+			return (-1);
+		}
+		*str = tmp;
+	}
+	(*str)[*len] = ch;
+	++*len;
+	(*str)[*len] = '\0';
+	return (0);
+}
+
+/*
+ * NODOC
+ */