Add fallback build paths search using environment variables

1 files changed, 216 insertions, 5 deletions

diff --git a/src/build_settings.cpp b/src/build_settings.cpp
index b458d8308..4d560bc00 100644
--- a/src/build_settings.cpp
+++ b/src/build_settings.cpp
@@ -1186,7 +1186,201 @@ void init_build_context(TargetMetrics *cross_target) {
 // NOTE(IC): In order to find Visual C++ paths without relying on environment variables.
 // NOTE(Jeroen): No longer needed in `main.cpp -> linker_stage`. We now resolve those paths in `init_build_paths`.
 #include "microsoft_craziness.h"
-#endif
+
+// NOTE(WalterPlinge): Environment variables can help to find Visual C++ and WinSDK paths for both
+// official and portable installations (like mmozeiko's portable msvc script). This will only use
+// the first paths it finds, and won't overwrite any values that `result` already has.
+bool find_portable_msvc_installation(gbAllocator allocator, Find_Result_Utf8 *result) {
+	if (build_context.metrics.arch != TargetArch_amd64 && build_context.metrics.arch != TargetArch_i386) {
+		return false;
+	}
+
+	bool sdk_found = false;
+	if(result->windows_sdk_root.len              > 0
+	&& result->windows_sdk_um_library_path.len   > 0
+	&& result->windows_sdk_ucrt_library_path.len > 0) {
+		sdk_found = true;
+	}
+
+	// We can find windows sdk using the following combination of env vars:
+	// (UniversalCRTSdkDir or WindowsSdkDir) and (WindowsSDKLibVersion or WindowsSDKVersion)
+	if (!sdk_found) {
+		// These appear to be suitable env vars used by Visual Studio
+		char const *win_sdk_ver_env = gb_get_env("WindowsSDKVersion", allocator);
+		char const *win_sdk_lib_env = gb_get_env("WindowsSDKLibVersion", allocator);
+		char const *win_sdk_dir_env = gb_get_env("WindowsSdkDir", allocator);
+		char const *crt_sdk_dir_env = gb_get_env("UniversalCRTSdkDir", allocator);
+		defer (gb_free(allocator, (void*)win_sdk_ver_env));
+		defer (gb_free(allocator, (void*)win_sdk_lib_env));
+		defer (gb_free(allocator, (void*)win_sdk_dir_env));
+		defer (gb_free(allocator, (void*)crt_sdk_dir_env));
+
+		// NOTE(WalterPlinge): If any combination is found, let's just assume they are correct
+		if ((win_sdk_ver_env || win_sdk_lib_env) && (win_sdk_dir_env || crt_sdk_dir_env)) {
+			//? Maybe we need to handle missing '\' at end of strings, so far it doesn't seem an issue
+			String dir = win_sdk_dir_env
+				? make_string_c(win_sdk_dir_env)
+				: make_string_c(crt_sdk_dir_env);
+			String ver = win_sdk_ver_env
+				? make_string_c(win_sdk_ver_env)
+				: make_string_c(win_sdk_lib_env);
+
+			// These have trailing '\' as we are just composing the path
+			String um_dir = build_context.metrics.arch == TargetArch_amd64
+				? make_string_c("um\\x64\\")
+				: make_string_c("um\\x86\\");
+			String ucrt_dir = build_context.metrics.arch == TargetArch_amd64
+				? make_string_c("ucrt\\x64\\")
+				: make_string_c("ucrt\\x86\\");
+
+			result->windows_sdk_root = concatenate3_strings(allocator, dir, make_string_c("Lib\\"), ver);
+			result->windows_sdk_um_library_path = concatenate_strings(allocator, result->windows_sdk_root, um_dir);
+			result->windows_sdk_ucrt_library_path = concatenate_strings(allocator, result->windows_sdk_root, ucrt_dir);
+
+			sdk_found = true;
+		}
+	}
+
+	// If we haven't found it yet, we can loop through LIB for specific folders
+	//? This may not be robust enough using `um\x64` and `ucrt\x64`
+	if (!sdk_found) {
+		char const *lib_env = gb_get_env("LIB", allocator);
+		defer (gb_free(allocator, (void*)lib_env));
+		if (lib_env) {
+			String lib = make_string_c(lib_env);
+
+			// NOTE(WalterPlinge): I don't know if there's a chance for the LIB variable
+			// to be set without a trailing '\' (apart from manually), so we can just
+			// check paths without it (see use of `String end` in the loop below)
+			String um_dir = build_context.metrics.arch == TargetArch_amd64
+				? make_string_c("um\\x64")
+				: make_string_c("um\\x86");
+			String ucrt_dir = build_context.metrics.arch == TargetArch_amd64
+				? make_string_c("ucrt\\x64")
+				: make_string_c("ucrt\\x86");
+
+			isize lo = {0};
+			isize hi = {0};
+			for (isize c = 0; c <= lib.len; c += 1) {
+				if (c != lib.len && lib[c] != ';') {
+					continue;
+				}
+				hi = c;
+				String dir = substring(lib, lo, hi);
+				defer (lo = hi + 1);
+
+				// Remove the last slash so we can match with the strings above
+				String end = dir[dir.len - 1] == '\\'
+					? substring(dir, 0, dir.len - 1)
+					: substring(dir, 0, dir.len);
+
+				// Find one and we can make the other
+				if (string_ends_with(end, um_dir)) {
+					result->windows_sdk_um_library_path = concatenate_strings(allocator, end, make_string_c("\\"));
+					break;
+				} else if (string_ends_with(end, ucrt_dir)) {
+					result->windows_sdk_ucrt_library_path = concatenate_strings(allocator, end, make_string_c("\\"));
+					break;
+				}
+			}
+
+			// Get the root from the one we found, and make the other
+			if (result->windows_sdk_um_library_path.len > 0) {
+				result->windows_sdk_root = substring(result->windows_sdk_um_library_path, 0, result->windows_sdk_um_library_path.len - 1 - um_dir.len);
+				result->windows_sdk_ucrt_library_path = concatenate3_strings(allocator, result->windows_sdk_root, ucrt_dir, make_string_c("\\"));
+			} else if (result->windows_sdk_ucrt_library_path.len > 0) {
+				result->windows_sdk_root = substring(result->windows_sdk_ucrt_library_path, 0, result->windows_sdk_ucrt_library_path.len - 1 - ucrt_dir.len);
+				result->windows_sdk_um_library_path = concatenate3_strings(allocator, result->windows_sdk_root, um_dir, make_string_c("\\"));
+			}
+
+			if (result->windows_sdk_root.len > 0) {
+				sdk_found = true;
+			}
+		}
+	}
+
+	// NOTE(WalterPlinge): So far this function assumes it will only be called if MSVC was
+	// installed using mmozeiko's portable msvc script, which uses the windows 10 sdk.
+	// This may need to be changed later if it ends up causing problems.
+	if (sdk_found && result->windows_sdk_version == 0) {
+		result->windows_sdk_version = 10;
+	}
+
+	bool vs_found = false;
+	if (result->vs_exe_path.len > 0 && result->vs_library_path.len > 0) {
+		vs_found = true;
+	}
+
+	// We can find visual studio using VCToolsInstallDir
+	if (!vs_found) {
+		char const *vctid_env = gb_get_env("VCToolsInstallDir", allocator);
+		defer (gb_free(allocator, (void*)vctid_env));
+		if (vctid_env) {
+			String vctid = make_string_c(vctid_env);
+			String exe = build_context.metrics.arch == TargetArch_amd64
+				? make_string_c("bin\\Hostx64\\x64\\")
+				: make_string_c("bin\\Hostx86\\x86\\");
+			String lib = build_context.metrics.arch == TargetArch_amd64
+				? make_string_c("lib\\x64\\")
+				: make_string_c("lib\\x86\\");
+			result->vs_exe_path = concatenate_strings(allocator, vctid, exe);
+			result->vs_library_path = concatenate_strings(allocator, vctid, lib);
+			vs_found = true;
+		}
+	}
+
+	// If we haven't found it yet, we can loop through Path for specific folders
+	if (!vs_found) {
+		char const *path_env = gb_get_env("Path", allocator);
+		defer (gb_free(allocator, (void*)path_env));
+		if (path_env) {
+			String path = make_string_c(path_env);
+
+			String exe = build_context.metrics.arch == TargetArch_amd64
+				? make_string_c("bin\\Hostx64\\x64")
+				: make_string_c("bin\\Hostx86\\x86");
+			String lib = build_context.metrics.arch == TargetArch_amd64
+				? make_string_c("lib\\x64")
+				: make_string_c("lib\\x86");
+
+			isize lo = {0};
+			isize hi = {0};
+			for (isize c = 0; c <= path.len; c += 1) {
+				if (c != path.len && path[c] != ';') {
+					continue;
+				}
+
+				hi = c;
+				String dir = substring(path, lo, hi);
+				defer (lo = hi + 1);
+
+				String end = dir[dir.len - 1] == '\\'
+					? substring(dir, 0, dir.len - 1)
+					: substring(dir, 0, dir.len);
+
+				// check if cl.exe and link.exe exist in this folder
+				String cl = concatenate_strings(allocator, end, make_string_c("\\cl.exe"));
+				String link = concatenate_strings(allocator, end, make_string_c("\\link.exe"));
+				defer (gb_free(allocator, cl.text));
+				defer (gb_free(allocator, link.text));
+
+				if (!string_ends_with(end, exe) || !gb_file_exists((char *)cl.text) || !gb_file_exists((char *)link.text)) {
+					continue;
+				}
+
+				String root = substring(end, 0, end.len - exe.len);
+
+				result->vs_exe_path = concatenate_strings(allocator, end, make_string_c("\\"));
+				result->vs_library_path = concatenate3_strings(allocator, root, lib, make_string_c("\\"));
+
+				vs_found = true;
+			}
+		}
+	}
+
+	return sdk_found && vs_found;
+}
+#endif defined(GB_SYSTEM_WINDOWS)
 
 // NOTE(Jeroen): Set/create the output and other paths and report an error as appropriate.
 // We've previously called `parse_build_flags`, so `out_filepath` should be set.
@@ -1227,11 +1421,28 @@ bool init_build_paths(String init_filename) {
 		if ((bc->command_kind & Command__does_build) && (!bc->ignore_microsoft_magic)) {
 			// NOTE(ic): It would be nice to extend this so that we could specify the Visual Studio version that we want instead of defaulting to the latest.
 			Find_Result_Utf8 find_result = find_visual_studio_and_windows_sdk_utf8();
-
-			if (find_result.windows_sdk_version == 0) {
-				gb_printf_err("Windows SDK not found.\n");
-				return false;
+			bool all_found =
+				find_result.windows_sdk_root.len              > 0 &&
+				find_result.windows_sdk_um_library_path.len   > 0 &&
+				find_result.windows_sdk_ucrt_library_path.len > 0 &&
+				find_result.vs_exe_path.len                   > 0 &&
+				find_result.vs_library_path.len               > 0;
+
+			if (find_result.windows_sdk_version == 0 || !all_found) {
+				if (!find_portable_msvc_installation(ha, &find_result)) {
+					gb_printf_err("Windows SDK not found.\n");
+					return false;
+				}
 			}
+#if 0
+	printf("windows_sdk_root:              %.*s\n", LIT(find_result.windows_sdk_root));
+	printf("windows_sdk_um_library_path:   %.*s\n", LIT(find_result.windows_sdk_um_library_path));
+	printf("windows_sdk_ucrt_library_path: %.*s\n", LIT(find_result.windows_sdk_ucrt_library_path));
+	printf("vs_exe_path:                   %.*s\n", LIT(find_result.vs_exe_path));
+	printf("vs_library_path:               %.*s\n", LIT(find_result.vs_library_path));
+
+	gb_exit(1);
+#endif
 
 			if (find_result.windows_sdk_um_library_path.len > 0) {
 				GB_ASSERT(find_result.windows_sdk_ucrt_library_path.len > 0);