Windows compatibility (#207)

* incorrect environment detection fixed
* use %zu instead of %ld for size_t
* fix rounding in integer division
* fix compiler error on Windows
* implement missed functions
* make linker available if MinGW environment is used
* make linker available under MSYS2 Clang64 and MSYS2 MinGW64

src/compiler/linker.c

@@ -1,5 +1,7 @@
 #include "compiler_internal.h"
 
+#include <llvm/Config/llvm-config.h>  // for LLVM_VERSION_STRING
+
 extern bool llvm_link_elf(const char **args, int arg_count, const char** error_string);
 extern bool llvm_link_macho(const char **args, int arg_count, const char** error_string);
 extern bool llvm_link_coff(const char **args, int arg_count, const char** error_string);
@@ -14,6 +16,51 @@ static void add_files(const char ***args, const char **files_to_link, unsigned f
 	}
 }
 
+static const char *join_strings(const char **args, unsigned count)
+{
+	char *res = "";
+	for (unsigned i = 0; i < count; ++i)
+	{
+		res = strcat_arena(res, args[i]);
+	}
+	return res;
+}
+
+static void prepare_msys2_linker_flags(const char ***args, const char **files_to_link, unsigned file_count)
+{
+	const char *root = getenv("MSYSTEM_PREFIX");
+#define add_arg(opt) vec_add(*args, opt)
+	add_arg("-m");
+	add_arg("i386pep");
+	add_arg("-Bdynamic");
+	add_arg(join_strings((const char *[]){root, "\\x86_64-w64-mingw32\\lib\\crt2.o"}, 2));
+	add_arg(join_strings((const char *[]){root, "\\x86_64-w64-mingw32\\lib\\crtbegin.o"}, 2));
+	add_arg(join_strings((const char *[]){"-L", root, "\\x86_64-w64-mingw32\\lib"}, 3));
+	add_arg(join_strings((const char *[]){"-L", root, "\\lib"}, 3));
+	add_arg(join_strings((const char *[]){"-L", root, "\\x86_64-w64-mingw32\\sys-root\\mingw\\lib"}, 3));
+	add_arg(join_strings((const char *[]){"-L", root, "\\lib\\clang\\", LLVM_VERSION_STRING, "\\lib\\windows"}, 5));
+	add_files(args, files_to_link, file_count);
+	add_arg("-lmingw32");
+	add_arg(join_strings((const char *[]){root, "\\lib\\clang\\", LLVM_VERSION_STRING, "\\lib\\windows\\libclang_rt.builtins-x86_64.a"}, 4));
+	add_arg("-lunwind");
+	add_arg("-lmoldname");
+	add_arg("-lmingwex");
+	add_arg("-lmsvcrt");
+	add_arg("-ladvapi32");
+	add_arg("-lshell32");
+	add_arg("-luser32");
+	add_arg("-lkernel32");
+	add_arg("-lmingw32");
+	add_arg(join_strings((const char *[]){root, "\\lib\\clang\\", LLVM_VERSION_STRING, "\\lib\\windows\\libclang_rt.builtins-x86_64.a"}, 4));
+	add_arg("-lunwind");
+	add_arg("-lmoldname");
+	add_arg("-lmingwex");
+	add_arg("-lmsvcrt");
+	add_arg("-lkernel32");
+	add_arg(join_strings((const char *[]){root, "\\x86_64-w64-mingw32\\lib\\crtend.o"}, 2));
+#undef add_arg
+}
+
 static bool link_exe(const char *output_file, const char **files_to_link, unsigned file_count)
 {
 	const char **args = NULL;
@@ -24,7 +71,20 @@ static bool link_exe(const char *output_file, const char **files_to_link, unsign
 	switch (platform_target.os)
 	{
 		case OS_TYPE_WIN32:
-			return false;
+			// TODO: properly detect if llvm-lld is available
+			// TODO: check if running inside MSYS2, it could be done via getting MSYSTEM environment variable
+			// https://stackoverflow.com/questions/65527286/how-to-check-if-my-program-is-running-on-mingwor-msys-shell-or-on-cmd
+			if (!platform_target.x64.is_mingw64) return false;
+			if (NULL == getenv("MSYSTEM")) return false;
+			if (!strcmp(getenv("MSYSTEM"), "CLANG64") || !strcmp(getenv("MSYSTEM"), "MINGW64"))
+			{
+				prepare_msys2_linker_flags(&args, files_to_link, file_count);
+			}
+			else
+			{
+				return false;
+			}
+			break;
 		case OS_TYPE_MACOSX:
 			add_files(&args, files_to_link, file_count);
 			vec_add(args, "-lSystem");
@@ -110,7 +170,7 @@ static bool link_exe(const char *output_file, const char **files_to_link, unsign
 	switch (platform_target.object_format)
 	{
 		case OBJ_FORMAT_COFF:
-			success = llvm_link_coff(args, (int)vec_size(args), &error);
+			success = (platform_target.x64.is_mingw64 ? llvm_link_mingw : llvm_link_coff)(args, (int)vec_size(args), &error);
 			break;
 		case OBJ_FORMAT_ELF:
 			success = llvm_link_elf(args, (int)vec_size(args), &error);

src/compiler/target.c

@@ -571,7 +571,7 @@ static OsType os_from_llvm_string(StringSlice os_string)
 
 static VendorType vendor_from_llvm_string(StringSlice slice)
 {
-#define STRCASE(_str, _vendor) if (slicestrcmp(slice, _str) == 0) return _vendor;
+#define STRCASE(_str, _vendor) if (slicestrcmp(slice, _str)) return _vendor;
 	STRCASE("apple", VENDOR_APPLE)
 	STRCASE("pc", VENDOR_PC)
 	STRCASE("scei", VENDOR_SCEI)

src/utils/file_utils.c

@@ -13,6 +13,10 @@
 #include <errno.h>
 #include "whereami.h"
 
+#if PLATFORM_WINDOWS
+#include <windows.h>
+#endif
+
 
 const char* expand_path(const char* path)
 {
@@ -186,7 +190,14 @@ void file_add_wildcard_files(const char ***files, const char *path, bool recursi
 		// Doesn't end with .c3
 		if (strncmp(&ent->d_name[namelen - 3], ".c3", 3) != 0)
 		{
-			if (ent->d_type == DT_DIR && ent->d_name[0] != '.' && recursive)
+			bool is_directory;
+#if PLATFORM_WINDOWS
+			struct stat st;
+			is_directory = stat(ent->d_name, &st) == 0 && S_ISDIR(st.st_mode);
+#else
+			is_directory = ent->d_type == DT_DIR;  // is it POSIX-compliant? As
+#endif
+			if (is_directory && ent->d_name[0] != '.' && recursive)
 			{
 				char *new_path = strndup(ent->d_name, namelen);
 				file_add_wildcard_files(files, new_path, recursive);
@@ -201,4 +212,20 @@ void file_add_wildcard_files(const char ***files, const char *path, bool recursi
 		vec_add(*files, name);
 	}
 	closedir(dir);
-}
+}
+
+#if PLATFORM_WINDOWS
+
+char *realpath(const char *path, char *const resolved_path)
+{
+	char *result = NULL == resolved_path ? calloc(PATH_MAX + 1, 1) : resolved_path;
+	if (NULL == result) return NULL;
+	if (!GetFullPathNameA(path, MAX_PATH, result, NULL))
+	{
+		if (NULL == resolved_path) free(result);
+		return NULL;
+	}
+	return result;
+}
+
+#endif

src/utils/lib.h

@@ -6,6 +6,10 @@
 
 #include "common.h"
 
+#if PLATFORM_WINDOWS
+#include "direct.h"
+#endif
+
 typedef struct Task_
 {
 	void (*task)(void *arg);
@@ -434,3 +438,18 @@ static inline StringSlice strtoslice(const char *data)
   typeof(_a) __a__ = (_a); \
   typeof(_b) __b__ = (_b); \
   __a__ < __b__ ? __a__ : __b__; })
+
+// Windows-specific code
+
+
+#if PLATFORM_WINDOWS
+
+int asprintf(char **strp, const char *fmt, ...);
+int vasprintf(char **strp, const char *fmt, va_list ap);
+char *strndup(const char *s, size_t len);
+
+char *realpath(const char *path, char *resolved_path);
+
+#define mkdir(name, unused) _mkdir(name)
+
+#endif

src/utils/malloc.c

@@ -31,7 +31,7 @@ void *malloc_arena(size_t mem)
 void print_arena_status(void)
 {
 	printf("-- ARENA INFO -- \n");
-	printf(" * Memory used:  %ld Kb\n", arena.allocated / 1024);
+	printf(" * Memory used:  %zu Kb\n", arena.allocated / 1024);
 	printf(" * Allocations: %d\n", allocations_done);
 }
 

src/utils/stringutils.c

@@ -59,4 +59,44 @@ char *strcat_arena(const char *a, const char *b)
 	memcpy(buffer + a_len, b, b_len);
 	buffer[a_len + b_len] = '\0';
 	return buffer;
-}
+}
+
+#if PLATFORM_WINDOWS
+
+int asprintf(char **strp, const char *fmt, ...)
+{
+	va_list args;
+	va_start(args, fmt);
+	int res = vasprintf(strp, fmt, args);
+	va_end(args);
+	return res;
+}
+
+int vasnprintf(char **strp, const char *fmt, va_list args)
+{
+	va_list args_copy;
+	va_copy(args_copy, args);
+	int res = vsprintf(NULL, fmt, args);
+	if (res < 0) goto END;
+	char *buf = calloc(res + 1, 1);
+	if (NULL == buf) goto END;
+	sprintf(buf, fmt, args_copy);  // this can't fail, right?
+	*strp = buf;
+	END:
+	va_end(args_copy);
+	return res;
+}
+
+char *strndup(const char *s, size_t n)
+{
+	n = strnlen(s, n);
+	char *t = calloc(n + 1, 1);
+	if (NULL != t)
+	{
+		memcpy(t, s, n);
+		t[n] = '\0';
+	}
+	return t;
+}
+
+#endif

src/utils/vmem.c

@@ -42,7 +42,7 @@ static inline void* mmap_allocate(Vmem *vmem, size_t to_allocate)
 	size_t allocated_after = to_allocate + vmem->allocated;
 #if PLATFORM_WINDOWS
 	size_t blocks_committed = vmem->committed / COMMIT_PAGE_SIZE;
-	size_t end_block = (allocated_after) / COMMIT_PAGE_SIZE;
+	size_t end_block = (allocated_after + COMMIT_PAGE_SIZE - 1) / COMMIT_PAGE_SIZE;  // round up
 	size_t blocks_to_allocate = end_block - blocks_committed;
 	if (blocks_to_allocate > 0)
 	{

wrapper/src/wrapper.cpp

@@ -65,6 +65,9 @@ static bool llvm_link(ObjFormat format, const char **args, int arg_count, const
 		case COFF:
 			if (lld::coff::link(arg_vector, false, output, output_err)) return true;
 			break;
+		case MINGW:
+			if (lld::mingw::link(arg_vector, false, output, output_err)) return true;
+			break;
 		default:
 			exit(-1);
 	}