mtmd, arg: fix utf8 handling on windows (#24779)

* mtmd, arg: fix utf8 handling on windows

* also fix ggml_fopen

* fix build fail

* also fix CLI

tools/mtmd/clip-impl.h

@@ -13,6 +13,14 @@
 #include <sstream>
 #include <vector>
 #include <memory>
+#include <fstream>
+
+#ifdef _WIN32
+#ifndef NOMINMAX
+#define NOMINMAX
+#endif
+#include <windows.h>
+#endif
 
 // Internal header for clip.cpp
 
@@ -661,6 +669,22 @@ struct clip_image_f32_batch {
 // common utils
 //
 
+#ifdef _WIN32
+static std::ifstream open_ifstream_binary(const std::string & fname) {
+    int wlen = MultiByteToWideChar(CP_UTF8, 0, fname.c_str(), -1, NULL, 0);
+    if (!wlen) {
+        throw std::runtime_error("failed to convert filename to UTF-16: " + fname);
+    }
+    std::vector<wchar_t> wfname(wlen);
+    (void)MultiByteToWideChar(CP_UTF8, 0, fname.c_str(), -1, wfname.data(), wlen);
+    return std::ifstream(wfname.data(), std::ios::binary);
+}
+#else
+static std::ifstream open_ifstream_binary(const std::string & fname) {
+    return std::ifstream(fname, std::ios::binary);
+}
+#endif
+
 static std::string string_format(const char * fmt, ...) {
     va_list ap;
     va_list ap2;

tools/mtmd/clip.cpp

@@ -1752,7 +1752,7 @@ struct clip_model_loader {
         std::map<std::string, size_t> tensor_offset;
         std::vector<ggml_tensor *> tensors_to_load;
 
-        auto fin = std::ifstream(fname, std::ios::binary);
+        auto fin = open_ifstream_binary(fname);
         if (!fin) {
             throw std::runtime_error(string_format("%s: failed to open %s\n", __func__, fname.c_str()));
         }

tools/mtmd/mtmd-cli.cpp

@@ -396,6 +396,9 @@ int main(int argc, char ** argv) {
 
     int n_predict = params.n_predict < 0 ? INT_MAX : params.n_predict;
 
+    console::init(params.simple_io, params.use_color);
+    atexit([]() { console::cleanup(); });
+
     // Ctrl+C handling
     {
 #if defined (__unix__) || (defined (__APPLE__) && defined (__MACH__))

tools/mtmd/mtmd-helper.cpp

@@ -582,13 +582,29 @@ mtmd_helper_bitmap_wrapper mtmd_helper_bitmap_init_from_buf(mtmd_context * ctx,
 }
 
 mtmd_helper_bitmap_wrapper mtmd_helper_bitmap_init_from_file(mtmd_context * ctx, const char * fname, bool placeholder) {
-    std::vector<unsigned char> buf;
+#ifdef _WIN32
+    int wlen = MultiByteToWideChar(CP_UTF8, 0, fname, -1, NULL, 0);
+    if (!wlen) {
+        LOG_ERR("Unable to convert filename to UTF-16: %s\n", fname);
+        return {nullptr, nullptr};
+    }
+    std::vector<wchar_t> wfname(wlen);
+    wlen = MultiByteToWideChar(CP_UTF8, 0, fname, -1, wfname.data(), wlen);
+    if (!wlen) {
+        LOG_ERR("Unable to convert filename to UTF-16: %s\n", fname);
+        return {nullptr, nullptr};
+    }
+    FILE * f = _wfopen(wfname.data(), L"rb");
+#else
     FILE * f = fopen(fname, "rb");
+#endif
     if (!f) {
         LOG_ERR("Unable to open file %s: %s\n", fname, strerror(errno));
         return {nullptr, nullptr};
     }
 
+    std::vector<unsigned char> buf;
+
     fseek(f, 0, SEEK_END);
     long file_size = ftell(f);
     fseek(f, 0, SEEK_SET);