+
+/* Target file operations. */
+
+static struct target_ops *
+default_fileio_target (void)
+{
+ /* If we're already connected to something that can perform
+ file I/O, use it. Otherwise, try using the native target. */
+ if (current_target.to_stratum >= process_stratum)
+ return current_target.beneath;
+ else
+ return find_default_run_target ("file I/O");
+}
+
+/* Open FILENAME on the target, using FLAGS and MODE. Return a
+ target file descriptor, or -1 if an error occurs (and set
+ *TARGET_ERRNO). */
+int
+target_fileio_open (const char *filename, int flags, int mode,
+ int *target_errno)
+{
+ struct target_ops *t;
+
+ for (t = default_fileio_target (); t != NULL; t = t->beneath)
+ {
+ if (t->to_fileio_open != NULL)
+ {
+ int fd = t->to_fileio_open (filename, flags, mode, target_errno);
+
+ if (targetdebug)
+ fprintf_unfiltered (gdb_stdlog,
+ "target_fileio_open (%s,0x%x,0%o) = %d (%d)\n",
+ filename, flags, mode,
+ fd, fd != -1 ? 0 : *target_errno);
+ return fd;
+ }
+ }
+
+ *target_errno = FILEIO_ENOSYS;
+ return -1;
+}
+
+/* Write up to LEN bytes from WRITE_BUF to FD on the target.
+ Return the number of bytes written, or -1 if an error occurs
+ (and set *TARGET_ERRNO). */
+int
+target_fileio_pwrite (int fd, const gdb_byte *write_buf, int len,
+ ULONGEST offset, int *target_errno)
+{
+ struct target_ops *t;
+
+ for (t = default_fileio_target (); t != NULL; t = t->beneath)
+ {
+ if (t->to_fileio_pwrite != NULL)
+ {
+ int ret = t->to_fileio_pwrite (fd, write_buf, len, offset,
+ target_errno);
+
+ if (targetdebug)
+ fprintf_unfiltered (gdb_stdlog,
+ "target_fileio_pwrite (%d,...,%d,%s) "
+ "= %d (%d)\n",
+ fd, len, pulongest (offset),
+ ret, ret != -1 ? 0 : *target_errno);
+ return ret;
+ }
+ }
+
+ *target_errno = FILEIO_ENOSYS;
+ return -1;
+}
+
+/* Read up to LEN bytes FD on the target into READ_BUF.
+ Return the number of bytes read, or -1 if an error occurs
+ (and set *TARGET_ERRNO). */
+int
+target_fileio_pread (int fd, gdb_byte *read_buf, int len,
+ ULONGEST offset, int *target_errno)
+{
+ struct target_ops *t;
+
+ for (t = default_fileio_target (); t != NULL; t = t->beneath)
+ {
+ if (t->to_fileio_pread != NULL)
+ {
+ int ret = t->to_fileio_pread (fd, read_buf, len, offset,
+ target_errno);
+
+ if (targetdebug)
+ fprintf_unfiltered (gdb_stdlog,
+ "target_fileio_pread (%d,...,%d,%s) "
+ "= %d (%d)\n",
+ fd, len, pulongest (offset),
+ ret, ret != -1 ? 0 : *target_errno);
+ return ret;
+ }
+ }
+
+ *target_errno = FILEIO_ENOSYS;
+ return -1;
+}
+
+/* Close FD on the target. Return 0, or -1 if an error occurs
+ (and set *TARGET_ERRNO). */
+int
+target_fileio_close (int fd, int *target_errno)
+{
+ struct target_ops *t;
+
+ for (t = default_fileio_target (); t != NULL; t = t->beneath)
+ {
+ if (t->to_fileio_close != NULL)
+ {
+ int ret = t->to_fileio_close (fd, target_errno);
+
+ if (targetdebug)
+ fprintf_unfiltered (gdb_stdlog,
+ "target_fileio_close (%d) = %d (%d)\n",
+ fd, ret, ret != -1 ? 0 : *target_errno);
+ return ret;
+ }
+ }
+
+ *target_errno = FILEIO_ENOSYS;
+ return -1;
+}
+
+/* Unlink FILENAME on the target. Return 0, or -1 if an error
+ occurs (and set *TARGET_ERRNO). */
+int
+target_fileio_unlink (const char *filename, int *target_errno)
+{
+ struct target_ops *t;
+
+ for (t = default_fileio_target (); t != NULL; t = t->beneath)
+ {
+ if (t->to_fileio_unlink != NULL)
+ {
+ int ret = t->to_fileio_unlink (filename, target_errno);
+
+ if (targetdebug)
+ fprintf_unfiltered (gdb_stdlog,
+ "target_fileio_unlink (%s) = %d (%d)\n",
+ filename, ret, ret != -1 ? 0 : *target_errno);
+ return ret;
+ }
+ }
+
+ *target_errno = FILEIO_ENOSYS;
+ return -1;
+}
+
+/* Read value of symbolic link FILENAME on the target. Return a
+ null-terminated string allocated via xmalloc, or NULL if an error
+ occurs (and set *TARGET_ERRNO). */
+char *
+target_fileio_readlink (const char *filename, int *target_errno)
+{
+ struct target_ops *t;
+
+ for (t = default_fileio_target (); t != NULL; t = t->beneath)
+ {
+ if (t->to_fileio_readlink != NULL)
+ {
+ char *ret = t->to_fileio_readlink (filename, target_errno);
+
+ if (targetdebug)
+ fprintf_unfiltered (gdb_stdlog,
+ "target_fileio_readlink (%s) = %s (%d)\n",
+ filename, ret? ret : "(nil)",
+ ret? 0 : *target_errno);
+ return ret;
+ }
+ }
+
+ *target_errno = FILEIO_ENOSYS;
+ return NULL;
+}
+
+static void
+target_fileio_close_cleanup (void *opaque)
+{
+ int fd = *(int *) opaque;
+ int target_errno;
+
+ target_fileio_close (fd, &target_errno);
+}
+
+/* Read target file FILENAME. Store the result in *BUF_P and
+ return the size of the transferred data. PADDING additional bytes are
+ available in *BUF_P. This is a helper function for
+ target_fileio_read_alloc; see the declaration of that function for more
+ information. */
+
+static LONGEST
+target_fileio_read_alloc_1 (const char *filename,
+ gdb_byte **buf_p, int padding)
+{
+ struct cleanup *close_cleanup;
+ size_t buf_alloc, buf_pos;
+ gdb_byte *buf;
+ LONGEST n;
+ int fd;
+ int target_errno;
+
+ fd = target_fileio_open (filename, FILEIO_O_RDONLY, 0700, &target_errno);
+ if (fd == -1)
+ return -1;
+
+ close_cleanup = make_cleanup (target_fileio_close_cleanup, &fd);
+
+ /* Start by reading up to 4K at a time. The target will throttle
+ this number down if necessary. */
+ buf_alloc = 4096;
+ buf = xmalloc (buf_alloc);
+ buf_pos = 0;
+ while (1)
+ {
+ n = target_fileio_pread (fd, &buf[buf_pos],
+ buf_alloc - buf_pos - padding, buf_pos,
+ &target_errno);
+ if (n < 0)
+ {
+ /* An error occurred. */
+ do_cleanups (close_cleanup);
+ xfree (buf);
+ return -1;
+ }
+ else if (n == 0)
+ {
+ /* Read all there was. */
+ do_cleanups (close_cleanup);
+ if (buf_pos == 0)
+ xfree (buf);
+ else
+ *buf_p = buf;
+ return buf_pos;
+ }
+
+ buf_pos += n;
+
+ /* If the buffer is filling up, expand it. */
+ if (buf_alloc < buf_pos * 2)
+ {
+ buf_alloc *= 2;
+ buf = xrealloc (buf, buf_alloc);
+ }
+
+ QUIT;
+ }
+}
+
+/* Read target file FILENAME. Store the result in *BUF_P and return
+ the size of the transferred data. See the declaration in "target.h"
+ function for more information about the return value. */
+
+LONGEST
+target_fileio_read_alloc (const char *filename, gdb_byte **buf_p)
+{
+ return target_fileio_read_alloc_1 (filename, buf_p, 0);
+}
+
+/* Read target file FILENAME. The result is NUL-terminated and
+ returned as a string, allocated using xmalloc. If an error occurs
+ or the transfer is unsupported, NULL is returned. Empty objects
+ are returned as allocated but empty strings. A warning is issued
+ if the result contains any embedded NUL bytes. */
+
+char *
+target_fileio_read_stralloc (const char *filename)
+{
+ gdb_byte *buffer;
+ LONGEST i, transferred;
+
+ transferred = target_fileio_read_alloc_1 (filename, &buffer, 1);
+
+ if (transferred < 0)
+ return NULL;
+
+ if (transferred == 0)
+ return xstrdup ("");
+
+ buffer[transferred] = 0;
+
+ /* Check for embedded NUL bytes; but allow trailing NULs. */
+ for (i = strlen (buffer); i < transferred; i++)
+ if (buffer[i] != 0)
+ {
+ warning (_("target file %s "
+ "contained unexpected null characters"),
+ filename);
+ break;
+ }
+
+ return (char *) buffer;
+}
+
+