server: add --media-path for local media files (#17697)

* server: add --media-path for local media files

* remove unused fn

common/arg.cpp

@@ -2488,12 +2488,29 @@ common_params_context common_params_parser_init(common_params & params, llama_ex
         "path to save slot kv cache (default: disabled)",
         [](common_params & params, const std::string & value) {
             params.slot_save_path = value;
+            if (!fs_is_directory(params.slot_save_path)) {
+                throw std::invalid_argument("not a directory: " + value);
+            }
             // if doesn't end with DIRECTORY_SEPARATOR, add it
             if (!params.slot_save_path.empty() && params.slot_save_path[params.slot_save_path.size() - 1] != DIRECTORY_SEPARATOR) {
                 params.slot_save_path += DIRECTORY_SEPARATOR;
             }
         }
     ).set_examples({LLAMA_EXAMPLE_SERVER}));
+    add_opt(common_arg(
+        {"--media-path"}, "PATH",
+        "directory for loading local media files; files can be accessed via file:// URLs using relative paths (default: disabled)",
+        [](common_params & params, const std::string & value) {
+            params.media_path = value;
+            if (!fs_is_directory(params.media_path)) {
+                throw std::invalid_argument("not a directory: " + value);
+            }
+            // if doesn't end with DIRECTORY_SEPARATOR, add it
+            if (!params.media_path.empty() && params.media_path[params.media_path.size() - 1] != DIRECTORY_SEPARATOR) {
+                params.media_path += DIRECTORY_SEPARATOR;
+            }
+        }
+    ).set_examples({LLAMA_EXAMPLE_SERVER}));
     add_opt(common_arg(
         {"--models-dir"}, "PATH",
         "directory containing models for the router server (default: disabled)",

common/common.cpp

@@ -694,7 +694,7 @@ bool string_parse_kv_override(const char * data, std::vector<llama_model_kv_over
 
 // Validate if a filename is safe to use
 // To validate a full path, split the path by the OS-specific path separator, and validate each part with this function
-bool fs_validate_filename(const std::string & filename) {
+bool fs_validate_filename(const std::string & filename, bool allow_subdirs) {
     if (!filename.length()) {
         // Empty filename invalid
         return false;
@@ -754,10 +754,14 @@ bool fs_validate_filename(const std::string & filename) {
             || (c >= 0xD800 && c <= 0xDFFF) // UTF-16 surrogate pairs
             || c == 0xFFFD // Replacement Character (UTF-8)
             || c == 0xFEFF // Byte Order Mark (BOM)
-            || c == '/' || c == '\\' || c == ':' || c == '*' // Illegal characters
+            || c == ':' || c == '*' // Illegal characters
             || c == '?' || c == '"' || c == '<' || c == '>' || c == '|') {
             return false;
         }
+        if (!allow_subdirs && (c == '/' || c == '\\')) {
+            // Subdirectories not allowed, reject path separators
+            return false;
+        }
     }
 
     // Reject any leading or trailing ' ', or any trailing '.', these are stripped on Windows and will cause a different filename
@@ -859,6 +863,11 @@ bool fs_create_directory_with_parents(const std::string & path) {
 #endif // _WIN32
 }
 
+bool fs_is_directory(const std::string & path) {
+    std::filesystem::path dir(path);
+    return std::filesystem::exists(dir) && std::filesystem::is_directory(dir);
+}
+
 std::string fs_get_cache_directory() {
     std::string cache_directory = "";
     auto ensure_trailing_slash = [](std::string p) {

common/common.h

@@ -485,6 +485,7 @@ struct common_params {
     bool log_json = false;
 
     std::string slot_save_path;
+    std::string media_path; // path to directory for loading media files
 
     float slot_prompt_similarity = 0.1f;
 
@@ -635,8 +636,9 @@ std::string string_from(const struct llama_context * ctx, const struct llama_bat
 // Filesystem utils
 //
 
-bool fs_validate_filename(const std::string & filename);
+bool fs_validate_filename(const std::string & filename, bool allow_subdirs = false);
 bool fs_create_directory_with_parents(const std::string & path);
+bool fs_is_directory(const std::string & path);
 
 std::string fs_get_cache_directory();
 std::string fs_get_cache_file(const std::string & filename);