snprintf(3)-related improvements.

configure.ac

@@ -47,7 +47,7 @@ AC_CHECK_FUNCS([arc4random_buf \
 	updwtmpx innetgr \
 	getspnam_r \
 	rpmatch \
-	memset_explicit explicit_bzero stpecpy stpeprintf])
+	memset_explicit explicit_bzero stpecpy seprintf])
 AC_SYS_LARGEFILE
 
 dnl Checks for typedefs, structures, and compiler characteristics.

lib/Makefile.am

@@ -197,10 +197,10 @@ libshadow_la_SOURCES = \
 	string/memset/memzero.h \
 	string/sprintf/aprintf.c \
 	string/sprintf/aprintf.h \
-	string/sprintf/snprintf.c \
-	string/sprintf/snprintf.h \
-	string/sprintf/stpeprintf.c \
-	string/sprintf/stpeprintf.h \
+	string/sprintf/seprintf.c \
+	string/sprintf/seprintf.h \
+	string/sprintf/stprintf.c \
+	string/sprintf/stprintf.h \
 	string/strchr/strchrcnt.c \
 	string/strchr/strchrcnt.h \
 	string/strchr/strchrscnt.c \

lib/audit_help.c

@@ -25,7 +25,7 @@
 #include "attr.h"
 #include "prototypes.h"
 #include "shadowlog.h"
-#include "string/sprintf/snprintf.h"
+#include "string/sprintf/stprintf.h"
 
 int audit_fd;
 

lib/commonio.c

@@ -37,7 +37,7 @@
 #include "sssd.h"
 #include "string/memset/memzero.h"
 #include "string/sprintf/aprintf.h"
-#include "string/sprintf/snprintf.h"
+#include "string/sprintf/stprintf.h"
 #include "string/strcmp/streq.h"
 #include "string/strcmp/strprefix.h"
 #include "string/strerrno.h"

lib/env.c

@@ -22,8 +22,7 @@
 #include "defines.h"
 #include "shadowlog.h"
 #include "string/sprintf/aprintf.h"
-#include "string/sprintf/snprintf.h"
-#include "string/sprintf/aprintf.h"
+#include "string/sprintf/stprintf.h"
 #include "string/strcmp/strprefix.h"
 #include "string/strdup/strdup.h"
 

lib/get_pid.c

@@ -14,7 +14,7 @@
 #include "atoi/getnum.h"
 #include "defines.h"
 #include "prototypes.h"
-#include "string/sprintf/snprintf.h"
+#include "string/sprintf/stprintf.h"
 #include "string/strerrno.h"
 
 

lib/hushed.c

@@ -21,7 +21,7 @@
 #include "defines.h"
 #include "getdef.h"
 #include "prototypes.h"
-#include "string/sprintf/snprintf.h"
+#include "string/sprintf/stprintf.h"
 #include "string/strcmp/streq.h"
 #include "string/strtok/stpsep.h"
 

lib/idmapping.c

@@ -27,7 +27,7 @@
 #include "prototypes.h"
 #include "shadowlog.h"
 #include "sizeof.h"
-#include "string/sprintf/stpeprintf.h"
+#include "string/sprintf/seprintf.h"
 #include "string/strcmp/streq.h"
 #include "string/strerrno.h"
 
@@ -184,13 +184,13 @@ void write_mapping(int proc_dir_fd, int ranges, const struct map_range *mappings
 	mapping = mappings;
 	for (idx = 0; idx < ranges; idx++, mapping++) {
 		/* Append this range to the string that will be written */
-		pos = stpeprintf(pos, end, "%lu %lu %lu\n",
+		pos = seprintf(pos, end, "%lu %lu %lu\n",
 		                 mapping->upper,
 		                 mapping->lower,
 		                 mapping->count);
 	}
 	if (pos == end || pos == NULL) {
-		fprintf(log_get_logfd(), _("%s: stpeprintf failed!\n"), log_get_progname());
+		fprintf(log_get_logfd(), _("%s: seprintf failed!\n"), log_get_progname());
 		exit(EXIT_FAILURE);
 	}
 

lib/nss.c

@@ -13,7 +13,7 @@
 #include "prototypes.h"
 #include "../libsubid/subid.h"
 #include "shadowlog.h"
-#include "string/sprintf/snprintf.h"
+#include "string/sprintf/stprintf.h"
 #include "string/strcmp/strcaseprefix.h"
 #include "string/strcmp/streq.h"
 #include "string/strcmp/strprefix.h"

lib/pwauth.c

@@ -25,7 +25,7 @@
 #include "pwauth.h"
 #include "getdef.h"
 #include "string/memset/memzero.h"
-#include "string/sprintf/snprintf.h"
+#include "string/sprintf/stprintf.h"
 #include "string/strcmp/streq.h"
 
 #ifdef SKEY

lib/salt.c

@@ -26,6 +26,7 @@
 #include "getdef.h"
 #include "prototypes.h"
 #include "shadowlog.h"
+#include "string/sprintf/stprintf.h"
 #include "string/strcmp/streq.h"
 
 
@@ -172,7 +173,7 @@ static /*@observer@*/void SHA_salt_rounds_to_buf (char *buf, unsigned long round
 	 */
 	assert (GENSALT_SETTING_SIZE > buf_begin + 17);
 
-	(void) snprintf (buf + buf_begin, 18, "rounds=%lu$", rounds);
+	stprintf(buf + buf_begin, 18, "rounds=%lu$", rounds);
 }
 
 #ifdef USE_BCRYPT
@@ -250,7 +251,7 @@ static /*@observer@*/void BCRYPT_salt_rounds_to_buf (char *buf, unsigned long ro
 	 */
 	assert (GENSALT_SETTING_SIZE > buf_begin + 3);
 
-	(void) snprintf (buf + buf_begin, 4, "%2.2lu$", rounds);
+	stprintf(buf + buf_begin, 4, "%2.2lu$", rounds);
 }
 #endif /* USE_BCRYPT */
 

lib/shell.c

@@ -15,7 +15,7 @@
 #include <errno.h>
 #include "prototypes.h"
 #include "defines.h"
-#include "string/sprintf/snprintf.h"
+#include "string/sprintf/stprintf.h"
 
 
 extern char **newenvp;

lib/string/README

@@ -213,14 +213,14 @@ sprintf/ - Formatted string creation
 	sprintf(3) variant that allocates.
 	It has better interface than asprintf(3).
 
-    stprintf()  // Current name: snprintf_()
+    stprintf()
 	snprintf(3) wrapper that reports truncation with -1.
 	If you need more than one call to form a string,
 	use seprintf() instead.
     stprintf_a()
 	Like stprintf(), but takes an array.
 
-    seprintf()  // Current name: stpeprintf())
+    seprintf()
 	Similar to stprintf(), but takes a pointer to the end instead of
 	a size.  This makes it safer for chaining several calls.
 

lib/string/sprintf/seprintf.c

@@ -0,0 +1,17 @@
+// SPDX-FileCopyrightText: 2022-2025, Alejandro Colomar <[email protected]>
+// SPDX-License-Identifier: BSD-3-Clause
+
+
+#include "config.h"
+
+#include "string/sprintf/seprintf.h"
+
+#include <stdarg.h>
+
+
+#if !defined(HAVE_SEPRINTF)
+extern inline char *seprintf(char *dst, const char end[0],
+    const char *restrict fmt, ...);
+extern inline char *vseprintf(char *dst, const char end[0],
+    const char *restrict fmt, va_list ap);
+#endif

lib/string/sprintf/seprintf.h

@@ -0,0 +1,66 @@
+// SPDX-FileCopyrightText: 2022-2025, Alejandro Colomar <[email protected]>
+// SPDX-License-Identifier: BSD-3-Clause
+
+
+#ifndef SHADOW_INCLUDE_LIB_STRING_SPRINTF_SEPRINTF_H_
+#define SHADOW_INCLUDE_LIB_STRING_SPRINTF_SEPRINTF_H_
+
+
+#include "config.h"
+
+#include <stdarg.h>
+#include <stddef.h>
+
+#include "attr.h"
+#include "string/sprintf/stprintf.h"
+
+
+#if !defined(HAVE_SEPRINTF)
+// seprintf - string end-pointer print formatted
+format_attr(printf, 3, 4)
+inline char *seprintf(char *dst, const char end[0], const char *restrict fmt,
+    ...);
+// vseprintf - va_list string end-pointer print formatted
+format_attr(printf, 3, 0)
+inline char *vseprintf(char *dst, const char end[0], const char *restrict fmt,
+    va_list ap);
+#endif
+
+
+#if !defined(HAVE_SEPRINTF)
+inline char *
+seprintf(char *dst, const char end[0], const char *restrict fmt, ...)
+{
+	char     *p;
+	va_list  ap;
+
+	va_start(ap, fmt);
+	p = vseprintf(dst, end, fmt, ap);
+	va_end(ap);
+
+	return p;
+}
+#endif
+
+
+#if !defined(HAVE_SEPRINTF)
+inline char *
+vseprintf(char *dst, const char end[0], const char *restrict fmt, va_list ap)
+{
+	int        len;
+	ptrdiff_t  size;
+
+	if (dst == NULL)
+		return NULL;
+
+	size = end - dst;
+	len = vstprintf(dst, size, fmt, ap);
+	if (len == -1)
+		return NULL;
+
+	return dst + len;
+}
+#endif
+
+
+#endif  // include guard