Implement lazy-loaded libcurl

- Uses `dlopen` to load libcurl at runtime for better portability.
- Replaces the FETCH_AVAILABLE macro with download_available() check.
- Provides descriptive error messages when libcurl is missing.

CMakeLists.txt

@@ -129,9 +129,6 @@ if(C3_USE_MIMALLOC)
     )
     FetchContent_MakeAvailable(mimalloc)
 endif()
-if (NOT WIN32)
-    find_package(CURL)
-endif()
 
 find_package(Git QUIET)
 if(C3_USE_TB AND GIT_FOUND AND EXISTS "${CMAKE_SOURCE_DIR}/.git")
@@ -606,12 +603,11 @@ if(MINGW)
     set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} -Wl,--stack,8388608")
 endif ()
 
-if (CURL_FOUND)
+if (NOT WIN32)
-    target_link_libraries(c3c ${CURL_LIBRARIES})
+    # For dlopen support
-    target_include_directories(c3c PRIVATE ${CURL_INCLUDE_DIRS})
+    if (CMAKE_DL_LIBS)
-    target_compile_definitions(c3c PUBLIC CURL_FOUND=1)
+        target_link_libraries(c3c ${CMAKE_DL_LIBS})
-else()
+    endif()
-    target_compile_definitions(c3c PUBLIC CURL_FOUND=0)
 endif()
 
 

src/build/build_options.c

@@ -259,9 +259,7 @@ static void project_usage()
 	PRINTF("Project Subcommands:");
 	print_cmd("view", "view the current projects structure.");
 	print_cmd("add-target <name>  <target_type>  [sources...]", "add a new target to the project.");
-	#if FETCH_AVAILABLE
+	print_cmd("fetch", "fetch missing project libraries.");
-		print_cmd("fetch", "fetch missing project libraries.");
-	#endif
 }
 
 static void project_view_usage()

src/build/project_manipulation.c

@@ -268,9 +268,14 @@ static void view_target(BuildParseContext context, JSONObject *target, bool verb
 
 
 
-#if FETCH_AVAILABLE
+
 void fetch_project(BuildOptions* options)
 {
+	if (!download_available())
+	{
+		error_exit("The 'project fetch' command requires libcurl to download dependencies.\n"
+				   "Please ensure libcurl is installed on your system.");
+	}
 	if (!file_exists(PROJECT_JSON5) && !file_exists(PROJECT_JSON))
 	{
 		error_exit("Failed: no project file found.");
@@ -343,12 +348,7 @@ void fetch_project(BuildOptions* options)
 		}
 	}
 }
-#else
+
-void fetch_project(BuildOptions* options)
-{
-	error_exit("Error: project fetch only available when compiled with cURL.");
-}
-#endif
 
 
 void add_libraries_to_project_file(const char** libs, const char* target_name) {

src/compiler/compiler.c

@@ -966,7 +966,7 @@ bool use_ansi(void)
 #endif
 }
 
-#if FETCH_AVAILABLE
+
 const char * vendor_fetch_single(const char* lib, const char* path) 
 {
 	const char *resource = str_printf("/c3lang/vendor/releases/download/latest/%s.c3l", lib);
@@ -993,6 +993,11 @@ void update_progress_bar(const char* lib, int current_step, int total_steps)
 
 void vendor_fetch(BuildOptions *options)
 {
+	if (!download_available())
+	{
+		error_exit("The 'vendor-fetch' command requires libcurl to download libraries.\n"
+				   "Please ensure libcurl is installed on your system.");
+	}
 	bool ansi = use_ansi();
 
 	if (str_eq(options->path, DEFAULT_PATH))
@@ -1061,12 +1066,7 @@ void vendor_fetch(BuildOptions *options)
 
 	if (ansi) printf("\033[32mFetching complete.\033[0m\t\t\n");
 }
-#else
+
-void vendor_fetch(BuildOptions *options)
-{
-	error_exit("Error: vendor-fetch only available when compiled with cURL.");
-}
-#endif
 
 void print_syntax(BuildOptions *options)
 {

src/utils/common.h

@@ -54,11 +54,6 @@
 #endif
 #endif
 
-#if CURL_FOUND || PLATFORM_WINDOWS
-#define FETCH_AVAILABLE 1
-#else
-#define FETCH_AVAILABLE 0
-#endif
 
 #define IS_GCC 0
 #define IS_CLANG 0

src/utils/fetch_msvc.c

@@ -136,7 +136,7 @@ static void closedir(DIR *dir)
 }
 #endif
 
-#if FETCH_AVAILABLE
+
 
 static int version_compare(const char *v1, const char *v2)
 {
@@ -509,6 +509,13 @@ static bool check_license(JSONObject *rj1_channel_items, bool accept_all)
 
 void fetch_msvc(BuildOptions *options)
 {
+	if (!download_available())
+	{
+		error_exit("Failed to find Windows SDK.\n"
+				   "Windows applications cannot be cross-compiled without it.\n"
+				   "To download the SDK automatically, please ensure libcurl is installed.\n"
+				   "Alternatively, provide the SDK path manually using --winsdk.");
+	}
 	verbose_level = options->verbosity_level;
 	const char *tmp_dir_base = dir_make_temp_dir();
 	if (!tmp_dir_base) error_exit("Failed to create temp directory");
@@ -749,13 +756,5 @@ void fetch_msvc(BuildOptions *options)
 
 	if (verbose_level == 0) file_delete_dir(tmp_dir_base);
 }
-#else
+
-void fetch_msvc(BuildOptions *options)
-{
-	error_exit("Failed to find Windows SDK.\n"
-			   "Windows applications cannot be cross-compiled without it.\n"
-			   "This build of c3c lacks cURL support and cannot download the SDK automatically.\n"
-			   "Please provide the SDK path manually using --winsdk.");
-}
-#endif
 

src/utils/http.c

@@ -105,8 +105,84 @@ END:
 	return NULL;
 }
 
-#elif CURL_FOUND
+bool download_available(void)
-#include <curl/curl.h>
+{
+	return true;
+}
+
+#elif PLATFORM_POSIX
+
+#include <dlfcn.h>
+
+typedef void CURL;
+typedef int CURLcode;
+typedef int CURLoption;
+
+#define CURLE_OK 0
+#define CURLOPT_URL 10002
+#define CURLOPT_FOLLOWLOCATION 52
+#define CURLOPT_VERBOSE 41
+#define CURLOPT_NOPROGRESS 43
+#define CURLOPT_FAILONERROR 45
+#define CURLOPT_WRITEFUNCTION 20011
+#define CURLOPT_WRITEDATA 10001
+#define CURLOPT_CAINFO 10065
+
+static void *libcurl = NULL;
+static CURL* (*ptr_curl_easy_init)(void);
+static CURLcode (*ptr_curl_easy_setopt)(CURL *, CURLoption, ...);
+static CURLcode (*ptr_curl_easy_perform)(CURL *);
+static void (*ptr_curl_easy_cleanup)(CURL *);
+static const char* (*ptr_curl_easy_strerror)(CURLcode);
+
+static bool load_curl(void)
+{
+	if (libcurl) return true;
+	const char *names[] = {
+#ifdef __APPLE__
+		"libcurl.4.dylib",
+		"libcurl.dylib",
+		"/usr/lib/libcurl.4.dylib",
+		"/usr/lib/libcurl.dylib",
+		"/opt/homebrew/lib/libcurl.dylib",
+		"/usr/local/lib/libcurl.dylib"
+#else
+		"libcurl.so.4",
+		"libcurl.so",
+		"libcurl.so.3",
+		"libcurl-gnutls.so.4",
+		"libcurl-nss.so.4"
+#endif
+	};
+
+	for (size_t i = 0; i < sizeof(names) / sizeof(names[0]); i++)
+	{
+		libcurl = dlopen(names[i], RTLD_LAZY);
+		if (libcurl) break;
+	}
+
+	if (!libcurl) return false;
+
+	ptr_curl_easy_init = dlsym(libcurl, "curl_easy_init");
+	ptr_curl_easy_setopt = dlsym(libcurl, "curl_easy_setopt");
+	ptr_curl_easy_perform = dlsym(libcurl, "curl_easy_perform");
+	ptr_curl_easy_cleanup = dlsym(libcurl, "curl_easy_cleanup");
+	ptr_curl_easy_strerror = dlsym(libcurl, "curl_easy_strerror");
+
+	if (!ptr_curl_easy_init || !ptr_curl_easy_setopt || !ptr_curl_easy_perform || !ptr_curl_easy_cleanup || !ptr_curl_easy_strerror)
+	{
+		dlclose(libcurl);
+		libcurl = NULL;
+		return false;
+	}
+
+	return true;
+}
+
+bool download_available(void)
+{
+	return load_curl();
+}
 
 static size_t write_data(void *ptr, size_t size, size_t nmemb, void *stream)
 {
@@ -115,35 +191,43 @@ static size_t write_data(void *ptr, size_t size, size_t nmemb, void *stream)
 
 const char *download_file(const char *url, const char *resource, const char *file_path)
 {
-	CURL *curl_handle = curl_easy_init();
+	if (!load_curl())
-	if (!curl_handle) error_exit("Could not initialize cURL subsystem.");
+	{
+		return "This build of c3c lacks cURL support and cannot download files automatically.\n"
+			   "Please ensure libcurl is installed on your system.";
+	}
+
+	CURL *curl_handle = ptr_curl_easy_init();
+	if (!curl_handle) return "Could not initialize cURL subsystem.";
+
 	FILE *file = fopen(file_path, "w+b");
 	if (!file)
 	{
-		curl_easy_cleanup(curl_handle);
+		ptr_curl_easy_cleanup(curl_handle);
 		return str_printf("Failed to open file '%s' for output", file_path);
 	}
 
 	const char *total_url = str_printf("%s%s", url, resource);
-	curl_easy_setopt(curl_handle, CURLOPT_URL, total_url);
+	ptr_curl_easy_setopt(curl_handle, CURLOPT_URL, total_url);
-	curl_easy_setopt(curl_handle, CURLOPT_FOLLOWLOCATION, 1L);
+	ptr_curl_easy_setopt(curl_handle, CURLOPT_FOLLOWLOCATION, 1L);
-	curl_easy_setopt(curl_handle, CURLOPT_VERBOSE, 0L);
+	ptr_curl_easy_setopt(curl_handle, CURLOPT_VERBOSE, 0L);
-	// Enable this later
+	ptr_curl_easy_setopt(curl_handle, CURLOPT_NOPROGRESS, 1L);
-	curl_easy_setopt(curl_handle, CURLOPT_NOPROGRESS, 1L);
+	ptr_curl_easy_setopt(curl_handle, CURLOPT_FAILONERROR, 1L);
-	curl_easy_setopt(curl_handle, CURLOPT_FAILONERROR, 1L);
+	ptr_curl_easy_setopt(curl_handle, CURLOPT_WRITEFUNCTION, write_data);
-	curl_easy_setopt(curl_handle, CURLOPT_WRITEFUNCTION, write_data);
+	ptr_curl_easy_setopt(curl_handle, CURLOPT_WRITEDATA, file);
-	curl_easy_setopt(curl_handle, CURLOPT_WRITEDATA, file);
+
-	CURLcode result = curl_easy_perform(curl_handle);
+	CURLcode result = ptr_curl_easy_perform(curl_handle);
 	if (result != CURLE_OK)
 	{
 		fclose(file);
 		remove(file_path);
-		const char *err_msg = str_dup(curl_easy_strerror(result));
+		const char *err_msg = str_dup(ptr_curl_easy_strerror(result));
-		curl_easy_cleanup(curl_handle);
+		ptr_curl_easy_cleanup(curl_handle);
 		return err_msg;
 	}
+
 	fclose(file);
-	curl_easy_cleanup(curl_handle);
+	ptr_curl_easy_cleanup(curl_handle);
 	return NULL;
 }
 

src/utils/lib.h

@@ -12,9 +12,8 @@
 #include "intrin.h"
 #endif
 
-#if FETCH_AVAILABLE
 const char *download_file(const char *url, const char *resource, const char *file_path);
-#endif
+bool download_available(void);
 
 #define ELEMENTLEN(x) (sizeof(x) / sizeof(x[0]))
 extern const char *compiler_exe_name;