util/FormatString: new library to replace g_strdup_printf()

src/util/FormatString.cxx

@@ -0,0 +1,68 @@
+/*
+ * Copyright (C) 2003-2013 The Music Player Daemon Project
+ * http://www.musicpd.org
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#include "FormatString.hxx"
+
+#include <string.h>
+#include <stdio.h>
+#include <stdlib.h>
+
+char *
+FormatNewV(const char *fmt, va_list args)
+{
+#ifndef WIN32
+	va_list tmp;
+	va_copy(tmp, args);
+	const int length = vsnprintf(NULL, 0, fmt, tmp);
+	va_end(tmp);
+
+	if (length <= 0)
+		/* wtf.. */
+		abort();
+
+	char *buffer = new char[length + 1];
+	vsnprintf(buffer, length + 1, fmt, args);
+	return buffer;
+#else
+	/* On mingw32, snprintf() expects a 64 bit integer instead of
+	   a "long int" for "%li".  This is not consistent with our
+	   expectation, so we're using plain sprintf() here, hoping
+	   the static buffer is large enough.  Sorry for this hack,
+	   but WIN32 development is so painful, I'm not in the mood to
+	   do it properly now. */
+
+	char buffer[16384];
+	vsprintf(buffer, fmt, args);
+
+	const size_t length = strlen(buffer);
+	char *p = new char[length + 1];
+	memcpy(p, buffer, length + 1);
+	return p;
+#endif
+}
+
+char *
+FormatNew(const char *fmt, ...)
+{
+	va_list args;
+	va_start(args, fmt);
+	char *p = FormatNewV(fmt, args);
+	va_end(args);
+	return p;
+}

src/util/FormatString.hxx

@@ -0,0 +1,43 @@
+/*
+ * Copyright (C) 2003-2013 The Music Player Daemon Project
+ * http://www.musicpd.org
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#ifndef MPD_FORMAT_STRING_HXX
+#define MPD_FORMAT_STRING_HXX
+
+#include "Compiler.h"
+
+#include <stdarg.h>
+
+/**
+ * Format into a newly allocated string.  The caller frees the return
+ * value with delete[].
+ */
+gcc_malloc gcc_nonnull_all
+char *
+FormatNewV(const char *fmt, va_list args);
+
+/**
+ * Format into a newly allocated string.  The caller frees the return
+ * value with delete[].
+ */
+gcc_malloc gcc_nonnull(1) gcc_printf(1,2)
+char *
+FormatNew(const char *fmt, ...);
+
+#endif