move the C sources to the subfolder pgf again for backwards compatibility

src/runtime/c/pgf/pgf.h

@@ -0,0 +1,117 @@
+#ifndef PGF_H_
+#define PGF_H_
+
+#ifdef __cplusplus
+#define EXTERN_C extern "C"
+#else
+#define EXTERN_C
+#endif
+
+#if defined(_MSC_VER)
+
+#if defined(COMPILING_PGF)
+#define PGF_API_DECL __declspec(dllexport) EXTERN_C
+#define PGF_API      __declspec(dllexport) EXTERN_C
+#else
+#define PGF_API_DECL __declspec(dllimport)
+#define PGF_API      ERROR_NOT_COMPILING_LIBPGF
+#endif
+#define PGF_INTERNAL_DECL
+#define PGF_INTERNAL
+
+#elif defined(__MINGW32__)
+
+#define PGF_API_DECL EXTERN_C
+#define PGF_API      EXTERN_C
+
+#define PGF_INTERNAL_DECL
+#define PGF_INTERNAL
+
+#else
+
+#define PGF_API_DECL EXTERN_C
+#define PGF_API      EXTERN_C
+
+#define PGF_INTERNAL_DECL  __attribute__ ((visibility ("hidden")))
+#define PGF_INTERNAL       __attribute__ ((visibility ("hidden")))
+
+#endif
+
+/* A generic structure to store text. The last field is variable length */
+typedef struct {
+    size_t size;
+    char text[];
+} PgfText;
+
+/* A generic structure to pass a callback for iteration over a collection */
+typedef struct PgfItor PgfItor;
+
+struct PgfItor {
+	void (*fn)(PgfItor* self, PgfText* key, void *value);
+};
+
+typedef struct PgfPGF PgfPGF;
+
+/* All functions that may fail take a reference to a PgfExn structure.
+ * It is used as follows:
+ * 
+ * - If everything went fine, the field type will be equal to
+ * PGF_EXN_NONE and all other fields will be zeroed.
+ *
+ * - If the exception was caused by external factors such as an error
+ * from a system call, then type will be PGF_EXN_SYSTEM_ERROR and
+ * the field code will contain the value of errno from the C runtime.
+ *
+ * - If the exception was caused by factors related to the GF runtime
+ * itself, then the error type is PGF_EXN_PGF_ERROR, and the field
+ * msg will contain a newly allocated string which must be freed from
+ * the caller.
+ */
+
+typedef enum {
+    PGF_EXN_NONE,
+    PGF_EXN_SYSTEM_ERROR,
+    PGF_EXN_PGF_ERROR
+}  PgfExnType;
+
+typedef struct {
+    PgfExnType type;
+    int code;
+    const char *msg;
+} PgfExn;
+
+/* Reads a PGF file and keeps it in memory. */
+PGF_API_DECL
+PgfPGF *pgf_read_pgf(const char* fpath, PgfExn* err);
+
+/* Reads a PGF file and stores the unpacked data in an NGF file
+ * ready to be shared with other process, or used for quick startup.
+ * The NGF file is platform dependent and should not be copied
+ * between machines. */
+PGF_API_DECL
+PgfPGF *pgf_boot_ngf(const char* pgf_path, const char* ngf_path, PgfExn* err);
+
+/* Tries to read the grammar from an already booted NGF file.
+ * If the file does not exist then a new one is created, and the
+ * grammar is set to be empty. It can later be populated with
+ * rules dynamically. */
+PGF_API_DECL
+PgfPGF *pgf_read_ngf(const char* fpath, PgfExn* err);
+
+/* Release the grammar when it is no longer needed. */
+PGF_API_DECL
+void pgf_free(PgfPGF *pgf);
+
+PGF_API_DECL
+PgfText *pgf_abstract_name(PgfPGF* pgf);
+
+PGF_API_DECL
+void pgf_iter_categories(PgfPGF* pgf, PgfItor* itor);
+
+PGF_API_DECL
+void pgf_iter_functions(PgfPGF* pgf, PgfItor* itor);
+
+PGF_API
+void pgf_iter_functions_by_cat(PgfPGF* pgf, PgfText* cat, PgfItor* itor);
+
+#endif // PGF_H_