Support full paths with $embed (#2335)

* Support full paths with `$embed`

---------

Co-authored-by: Christoffer Lerno <christoffer@aegik.com>

releasenotes.md

@@ -31,6 +31,7 @@
 - Deprecate allocator::heap() and allocator::temp()
 - Add `thread::fence` providing a thread fence.
 - Place output in `out` by default for projects. Use temp folder for building at the command line.
+- Allow absolute paths for `$embed`.
 
 ### Fixes
 - mkdir/rmdir would not work properly with substring paths on non-windows platforms.

src/compiler/sema_expr.c

@@ -9996,12 +9996,12 @@ static inline bool sema_expr_analyse_embed(SemaContext *context, Expr *expr, boo
 		}
 	}
 	if (!expr_is_const_string(filename)) RETURN_SEMA_ERROR(filename, "A compile time string was expected.");
-
+	if (!filename->const_expr.bytes.len) RETURN_SEMA_ERROR(filename, "Expected a non-empty string.");
 	CompilationUnit *unit = context->unit;
 	const char *string = filename->const_expr.bytes.ptr;
 	char *path;
 	char *name;
-	if (file_namesplit(unit->file->full_path, &name, &path))
+	if (file_path_is_relative(string) && file_namesplit(unit->file->full_path, &name, &path))
 	{
 		string = file_append_path(path, string);
 	}

src/utils/file_utils.c

@@ -564,6 +564,20 @@ bool file_exists(const char *path)
 	return S_ISDIR(st.st_mode) || S_ISREG(st.st_mode) || S_ISREG(st.st_mode);
 }
 
+bool file_path_is_relative(const char *file_name)
+{
+	assert(file_name);
+	size_t len = strlen(file_name);
+	if (!len) return false;
+
+	// returns !full_path condition
+#if PLATFORM_WINDOWS
+	return !(file_name[0] == '\\' || (len >= 2 && char_is_letter(file_name[0]) && file_name[1] == ':'));
+#else
+	return file_name[0] != '/';
+#endif
+}
+
 #define PATH_BUFFER_SIZE 16384
 static char path_buffer[PATH_BUFFER_SIZE];
 

src/utils/lib.h

@@ -80,6 +80,7 @@ bool file_delete_file(const char *path);
 void file_delete_dir(const char *path);
 bool file_is_dir(const char *file);
 bool file_exists(const char *path);
+bool file_path_is_relative(const char *file_name);
 FILE *file_open_read(const char *path);
 bool file_touch(const char *path);
 char *file_read_binary(const char *path, size_t *size);