Cleanup: move overflow safe alloc code into libsquashfs

There were only a hand full of instances outside libsquashfs that used
the alloc code. In most cases, the thing allocated hat its size derived
from something already in memory anyway, so it is safe to assume its
size fits into a size_t.

At the same time, the opencoded Windows path conversion functions are
all unified into a single helper function.

Signed-off-by: David Oberhollenzer <david.oberhollenzer@sigma-star.at>

1 files changed, 43 insertions, 0 deletions

diff --git a/lib/compat/path_to_windows.c b/lib/compat/path_to_windows.c
new file mode 100644
index 0000000..ff3a5d2
--- /dev/null
+++ b/lib/compat/path_to_windows.c
@@ -0,0 +1,43 @@
+/* SPDX-License-Identifier: GPL-3.0-or-later */
+/*
+ * path_to_windows.c
+ *
+ * Copyright (C) 2019 David Oberhollenzer <goliath@infraroot.at>
+ */
+#include "config.h"
+#include "compat.h"
+
+#include <stdlib.h>
+#include <stdio.h>
+
+#if defined(_WIN32) || defined(__WINDOWS__)
+WCHAR *path_to_windows(const char *input)
+{
+	WCHAR *wpath, *ptr;
+	DWORD length;
+
+	length = MultiByteToWideChar(CP_UTF8, 0, input, -1, NULL, 0);
+	if (length <= 0) {
+		fprintf(stderr, "Converting UTF-8 path to UTF-16: %ld\n",
+			GetLastError());
+		return NULL;
+	}
+
+	wpath = calloc(sizeof(wpath[0]), length + 1);
+	if (wpath == NULL) {
+		fprintf(stderr,
+			"Converting UTF-8 path to UTF-16: out of memory\n");
+		return NULL;
+	}
+
+	MultiByteToWideChar(CP_UTF8, 0, input, -1, wpath, length + 1);
+	wpath[length] = '\0';
+
+	for (ptr = wpath; *ptr != '\0'; ++ptr) {
+		if (*ptr == '/')
+			*ptr = '\\';
+	}
+
+	return wpath;
+}
+#endif