Android support

include/VFS.h

@@ -0,0 +1,133 @@
+/*************************************************************************
+ *									 *
+ *	 YAP Prolog 							 *
+ *									 *
+ *	Yap Prolog was developed at NCCUP - Universidade do Porto	 *
+ *									 *
+ * Copyright L.Damas, V.S.Costa and Universidade do Porto 1985-1997	 *
+ *									 *
+ **************************************************************************
+ *									 *
+ * File:		VFS.h						 *
+ * Last rev:	5/2/88							 *
+ * mods: *
+ * comments:	Virtual File System Access for YAP			 *
+ *									 *
+ *************************************************************************/
+#ifndef VFS_H
+#define VFS_H 1
+#include <string.h>
+#if HAVE_SYS_STAT_H
+#include <sys/stat.h>
+#endif
+
+#ifdef _WIN32
+#include <stdint.h>
+typedef uintptr_t uid_t;
+typedef uintptr_t gid_t;
+#endif
+
+typedef struct {
+  dev_t st_dev;                     /* ID of device containing file */
+  mode_t st_mode;                   /* Mode of file (see below) */
+  uid_t st_uid;                     /* User ID of the file */
+  gid_t st_gid;                     /* Group ID of the file */
+  struct timespec st_atimespec;     /* time of last access */
+  struct timespec st_mtimespec;     /* time of last data modification */
+  struct timespec st_ctimespec;     /* time of last status change */
+  struct timespec st_birthtimespec; /* time of file creation(birth) */
+#if __ANDROID__
+  off64_t st_size; /* file size, in bytes */
+#else
+  off_t st_size; /* file size, in bytes */
+#endif
+} vfs_stat;
+
+typedef enum vfs_flags {
+  VFS_CAN_WRITE = 0x1,     /// we can write to files in this space
+  VFS_CAN_EXEC = 0x2,      /// we can execute files in this space
+  VFS_CAN_SEEK = 0x4,      /// we can seek within files in this space
+  VFS_HAS_PREFIX = 0x8,    /// has a prefix that identifies a file in this space
+  VFS_HAS_SUFFIX = 0x10,   /// has a suffix that describes the file.
+  VFS_HAS_FUNCTION = 0x10, /// has a suffix that describes the file.
+} vfs_flags_t;
+
+typedef union {
+  struct vfs *vfs;
+  uintptr_t cell;
+  size_t sz;
+  void *pt;
+  uintptr_t scalar;
+#if __ANDROID__
+  AAssetManager *mgr;
+  AAsset *asset;
+#endif
+} cell_size_t;
+
+typedef struct vfs {
+  const char *name; /// A text that explains the file system
+  uintptr_t vflags; /// the main flags describing the operation of the Fs.
+  /// a way to identify a file in this VFS: two special cases, prefix and suffix
+  const char *prefix;
+  const char *suffix;
+  bool (*id)(struct vfs *me, const char *s);
+  /** operations */
+  bool (*open)(struct vfs *me, struct stream_desc *st, const char *s,
+               const char *io_mode);
+  ; /// open an object
+  /// in this space, usual w,r,a,b flags plus B (store in a buffer)
+  bool (*close)(struct stream_desc *stream);   /// close the object
+  int (*get_char)(struct stream_desc *stream); /// get an octet to the stream
+  int (*putc)(int ch,
+              struct stream_desc *stream); /// output an octet to the stream
+  int64_t (*seek)(struct stream_desc *stream, int64_t offset,
+                  int whence); /// jump around the stream
+  void *(*opendir)(struct vfs *me,
+                   const char *s); /// open a directory object, if one exists
+  const char *(*nextdir)(
+      void *d); /// walk to the next entry in a directory object
+  void (*closedir)(void *d);
+  ; /// close access a directory object
+  bool (*stat)(struct vfs *me, const char *s,
+               vfs_stat *); /// obtain size, age, permissions of a file.
+  bool (*isdir)(struct vfs *me, const char *s); /// verify whether is directory.
+  bool (*exists)(struct vfs *me,
+                 const char *s); /// verify whether a file exists.
+  bool (*chdir)(struct vfs *me,
+                const char *s);      /// set working directory (may be virtual).
+  encoding_t enc;                    /// how the file is encoded.
+  YAP_Term (*parsers)(void *stream); // a set of parsers that can read the
+                                     // stream and generate a YAP_Term
+  int (*writers)(int ch, void *stream);
+  ; /// convert a YAP_Term into this space
+  const char *virtual_cwd;
+  /** VFS dep
+      endent area */
+  cell_size_t priv[4];
+  struct vfs *next;
+} VFS_t;
+
+extern VFS_t *GLOBAL_VFS;
+
+static inline VFS_t *vfs_owner(const char *fname) {
+  return NULL;
+  VFS_t *me = GLOBAL_VFS;
+  int d;
+  size_t sz0 = strlen(fname);
+
+  while (me) {
+    if (me->vflags & VFS_HAS_PREFIX && strstr(fname, me->prefix))
+      return me;
+    size_t sz = strlen(me->suffix);
+    if (me->vflags & VFS_HAS_SUFFIX && (d = (sz0 - sz)) >= 0 &&
+        strcmp(fname + d, me->suffix) == 0)
+      return me;
+    if (me->vflags & VFS_HAS_FUNCTION && (me->id(me, fname))) {
+      return me;
+    }
+    me = me->next;
+  }
+  return NULL;
+}
+
+#endif