Move gfs API to separate .cpp file

Fixes: #424

internal/c/libqb.h

@@ -27,20 +27,6 @@ qbs *func_space(int32 spaces);
 void makefit(qbs *text);
 void qbg_sub_window(float, float, float, float, int32);
 extern int32 autodisplay;
-// GFS forward references
-int32 gfs_eof_passed(int32 i);
-int32 gfs_eof_reached(int32 i);
-int64 gfs_getpos(int32 i);
-int32 gfs_fileno_valid(int32 f);
-int32 gfs_fileno_freefile(); // like FREEFILE
-void gfs_fileno_use(int32 f, int32 i);
-int32 gfs_open(qbs *filename, int32 access, int32 restrictions, int32 how);
-int32 gfs_close(int32 i);
-int64 gfs_lof(int32 i);
-int32 gfs_setpos(int32 i, int64 position);
-int32 gfs_write(int32 i, int64 position, uint8 *data, int64 size);
-int32 gfs_read(int32 i, int64 position, uint8 *data, int64 size);
-int64 gfs_read_bytes();
 
 // keyhit cyclic buffer
 extern int64 keyhit[8192];

internal/c/libqb/build.mk

@@ -6,6 +6,7 @@ libqb-objs-y += $(PATH_LIBQB)/src/filepath.o
 libqb-objs-y += $(PATH_LIBQB)/src/filesystem.o
 libqb-objs-y += $(PATH_LIBQB)/src/datetime.o
 libqb-objs-y += $(PATH_LIBQB)/src/error_handle.o
+libqb-objs-y += $(PATH_LIBQB)/src/gfs.o
 libqb-objs-y += $(PATH_LIBQB)/src/mem.o
 libqb-objs-y += $(PATH_LIBQB)/src/rounding.o
 libqb-objs-y += $(PATH_LIBQB)/src/qbs.o

internal/c/libqb/include/gfs.h

@@ -0,0 +1,116 @@
+#pragma once
+
+#include <stdint.h>
+#include <iostream>
+
+#include "qbs.h"
+
+#ifdef QB64_WINDOWS
+#    define GFS_WINDOWS
+
+#    include <wtypes.h>
+#endif
+#ifndef GFS_WINDOWS
+#    define GFS_C
+#endif
+
+
+/* Generic File System (GFS)
+    GFS allows OS specific access whilst still maintaining 'pure' C-based routines for
+    multiplatform compatibility. 'Pure' C-based routines may not allow certain functionality,
+    such as partial file locking.
+    GFS handles/indexes are independent of QB64 handles/indexes to allow for internal files
+    to be open but not interfere with the QB64 file handle numbers.
+
+    GFS error codes:
+    -1 non-specific fail
+    -2 invalid handle
+    -3 bad/incorrect file mode
+    -4 illegal function call (input is out of range)
+    -5 file not found (win:2)
+    -6 path not found (win:3)
+    -7 access/permission denied (win:5,19)
+    -8 device unavailable/drive invalid (win:15,21)
+    -9 path/file access error
+    -10 read past eof
+    -11 bad file name
+*/
+
+struct gfs_file_struct { // info applicable to all files
+    int64_t id;            // a unique ID given to all files (currently only referenced by the FIELD statement to remove old field conditions)
+    uint8_t open;
+    uint8_t read;
+    uint8_t write;
+    uint8_t lock_read;
+    uint8_t lock_write;
+    int64_t pos;           //-1=unknown
+    uint8_t eof_reached;   // read last character of file (set/reset by gfs_read only)
+    uint8_t eof_passed;    // attempted to read past eof (set/reset by gfs_read only)
+    int32_t fileno;        // link to fileno index
+    uint8_t type;          // qb access method (1=RANDOM,2=BINARY,3=INPUT,4=OUTPUT)
+    int64_t record_length; // used by RANDOM
+    uint8_t *field_buffer;
+    qbs **field_strings;   // list of qbs pointers linked to this file
+    int32_t field_strings_n; // number of linked strings
+    int64_t column;          // used by OUTPUT/APPEND to tab correctly (base 0)
+    // GFS_C data follows: (unused by custom GFS interfaces)
+    std::fstream *file_handle;
+    std::ofstream *file_handle_o;
+    // COM port data follows (*=default)
+    uint8_t com_port;              // 0=not a com port
+    int32_t com_baud_rate;         //(bits per second)75,110,150,300*,600,1200,1800,2400,9600,?
+    int8_t com_parity;             //[0]N,[1]E*,[2]O,[3]S,[4]M,[5]PE(none,even*,odd,space,mark,error-checking)
+    int8_t com_data_bits_per_byte; // 5,6,7*,8
+    int8_t com_stop_bits;          //[10]1,[15]1.5,[20]2
+    // The default value is 1 for baud rates greater than 110. For
+    // baud rates less than or equal to 110, the default value is
+    // 1.5 when data is 5; otherwise, the value is 2.
+    int8_t com_bin_asc; //[0]=BIN*,[1]=ASC
+    int8_t com_asc_lf;  //[0]omit*,[1]LF(only valid with ASC)
+    // note: rb_x and tb_x are ignored by QB64 (receive and transmit buffer sizes)
+    int8_t com_rs;    //[0]detect*,[1]dont-detect
+    int32_t com_cd_x; // 0*-65535
+    int32_t com_cs_x; // 1000*,0-65535
+    int32_t com_ds_x; // 1000*,0-65535
+    int32_t com_op_x;
+    //                 OP not used:          x omitted:     x specified:
+    //                 10 times the CD or    10000 ms       0 - 65,535 milliseconds
+    //                 DS timeout value,
+    //                 whichever is greater
+
+    // SCRN: support follows
+    uint8_t scrn; // 0 = not a file opened as "SCRN:"
+};
+
+#ifdef GFS_WINDOWS
+// FIXME: Eww
+struct gfs_file_win_struct { // info applicable to WINDOWS OS files
+    HANDLE file_handle;
+};
+extern gfs_file_win_struct *gfs_file_win;
+#endif
+
+
+
+int32_t gfs_eof_passed(int32_t i);
+int32_t gfs_eof_reached(int32_t i);
+int64_t gfs_getpos(int32_t i);
+int32_t gfs_fileno_valid(int32_t f);
+int32_t gfs_fileno_freefile(); // like FREEFILE
+void gfs_fileno_use(int32_t f, int32_t i);
+int32_t gfs_open(qbs *filename, int32_t access, int32_t restrictions, int32_t how);
+int32_t gfs_close(int32_t i);
+int64_t gfs_lof(int32_t i);
+int32_t gfs_setpos(int32_t i, int64_t position);
+int32_t gfs_write(int32_t i, int64_t position, uint8_t *data, int64_t size);
+int32_t gfs_read(int32_t i, int64_t position, uint8_t *data, int64_t size);
+int64_t gfs_read_bytes();
+
+int32_t gfs_lock(int32_t i, int64_t offset_start, int64_t offset_end);
+int32_t gfs_unlock(int32_t i, int64_t offset_start, int64_t offset_end);
+
+int32_t gfs_get_fileno(int file_number);
+gfs_file_struct *gfs_get_file_struct(int fileno);
+
+void gfs_close_all_files();
+