--- /dev/null
+/* Copyright (C) 2001, 2006 Free Software Foundation, Inc.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+\f
+
+/* This is the C part of the (ice-9 rw) module. */
+
+#ifdef HAVE_CONFIG_H
+# include <config.h>
+#endif
+
+#include <errno.h>
+#include <string.h>
+
+#include "libguile/_scm.h"
+#include "libguile/fports.h"
+#include "libguile/ports.h"
+#include "libguile/root.h"
+#include "libguile/rw.h"
+#include "libguile/strings.h"
+#include "libguile/validate.h"
+#include "libguile/modules.h"
+#include "libguile/strports.h"
+
+#ifdef HAVE_UNISTD_H
+#include <unistd.h>
+#endif
+#ifdef HAVE_IO_H
+#include <io.h>
+#endif
+
+\f
+
+#if defined (EAGAIN)
+#define SCM_MAYBE_EAGAIN || errno == EAGAIN
+#else
+#define SCM_MAYBE_EAGAIN
+#endif
+
+#if defined (EWOULDBLOCK)
+#define SCM_MAYBE_EWOULDBLOCK || errno == EWOULDBLOCK
+#else
+#define SCM_MAYBE_EWOULDBLOCK
+#endif
+
+/* MAYBE there is EAGAIN way of defining this macro but now I EWOULDBLOCK. */
+#define SCM_EBLOCK(errno) \
+ (0 SCM_MAYBE_EAGAIN SCM_MAYBE_EWOULDBLOCK)
+
+SCM_DEFINE (scm_read_string_x_partial, "read-string!/partial", 1, 3, 0,
+ (SCM str, SCM port_or_fdes, SCM start, SCM end),
+ "Read characters from a port or file descriptor into a\n"
+ "string @var{str}. A port must have an underlying file\n"
+ "descriptor --- a so-called fport. This procedure is\n"
+ "scsh-compatible and can efficiently read large strings.\n"
+ "It will:\n\n"
+ "@itemize\n"
+ "@item\n"
+ "attempt to fill the entire string, unless the @var{start}\n"
+ "and/or @var{end} arguments are supplied. i.e., @var{start}\n"
+ "defaults to 0 and @var{end} defaults to\n"
+ "@code{(string-length str)}\n"
+ "@item\n"
+ "use the current input port if @var{port_or_fdes} is not\n"
+ "supplied.\n"
+ "@item\n"
+ "return fewer than the requested number of characters in some\n"
+ "cases, e.g., on end of file, if interrupted by a signal, or if\n"
+ "not all the characters are immediately available.\n"
+ "@item\n"
+ "wait indefinitely for some input if no characters are\n"
+ "currently available,\n"
+ "unless the port is in non-blocking mode.\n"
+ "@item\n"
+ "read characters from the port's input buffers if available,\n"
+ "instead from the underlying file descriptor.\n"
+ "@item\n"
+ "return @code{#f} if end-of-file is encountered before reading\n"
+ "any characters, otherwise return the number of characters\n"
+ "read.\n"
+ "@item\n"
+ "return 0 if the port is in non-blocking mode and no characters\n"
+ "are immediately available.\n"
+ "@item\n"
+ "return 0 if the request is for 0 bytes, with no\n"
+ "end-of-file check.\n"
+ "@end itemize")
+#define FUNC_NAME s_scm_read_string_x_partial
+{
+ char *dest;
+ size_t offset;
+ long read_len;
+ long chars_read = 0;
+ int fdes;
+
+ {
+ size_t last;
+
+ SCM_VALIDATE_STRING (1, str);
+ scm_i_get_substring_spec (scm_i_string_length (str),
+ start, &offset, end, &last);
+ read_len = last - offset;
+ }
+
+ if (scm_is_integer (port_or_fdes))
+ fdes = scm_to_int (port_or_fdes);
+ else
+ {
+ SCM port = (SCM_UNBNDP (port_or_fdes)?
+ scm_current_input_port () : port_or_fdes);
+
+ SCM_VALIDATE_OPFPORT (2, port);
+ SCM_VALIDATE_INPUT_PORT (2, port);
+
+ /* if there's anything in the port buffers, use it, but then
+ don't touch the file descriptor. otherwise the
+ "return immediately if something is available" rule may
+ be violated. */
+ dest = scm_i_string_writable_chars (str) + offset;
+ chars_read = scm_take_from_input_buffers (port, dest, read_len);
+ scm_i_string_stop_writing ();
+ fdes = SCM_FPORT_FDES (port);
+ }
+
+ if (chars_read == 0 && read_len > 0) /* don't confuse read_len == 0 with
+ EOF. */
+ {
+ dest = scm_i_string_writable_chars (str) + offset;
+ SCM_SYSCALL (chars_read = read (fdes, dest, read_len));
+ scm_i_string_stop_writing ();
+ if (chars_read == -1)
+ {
+ if (SCM_EBLOCK (errno))
+ chars_read = 0;
+ else
+ SCM_SYSERROR;
+ }
+ else if (chars_read == 0)
+ {
+ scm_remember_upto_here_1 (str);
+ return SCM_BOOL_F;
+ }
+ }
+
+ scm_remember_upto_here_1 (str);
+ return scm_from_long (chars_read);
+}
+#undef FUNC_NAME
+
+SCM_DEFINE (scm_write_string_partial, "write-string/partial", 1, 3, 0,
+ (SCM str, SCM port_or_fdes, SCM start, SCM end),
+ "Write characters from a string @var{str} to a port or file\n"
+ "descriptor. A port must have an underlying file descriptor\n"
+ "--- a so-called fport. This procedure is\n"
+ "scsh-compatible and can efficiently write large strings.\n"
+ "It will:\n\n"
+ "@itemize\n"
+ "@item\n"
+ "attempt to write the entire string, unless the @var{start}\n"
+ "and/or @var{end} arguments are supplied. i.e., @var{start}\n"
+ "defaults to 0 and @var{end} defaults to\n"
+ "@code{(string-length str)}\n"
+ "@item\n"
+ "use the current output port if @var{port_of_fdes} is not\n"
+ "supplied.\n"
+ "@item\n"
+ "in the case of a buffered port, store the characters in the\n"
+ "port's output buffer, if all will fit. If they will not fit\n"
+ "then any existing buffered characters will be flushed\n"
+ "before attempting\n"
+ "to write the new characters directly to the underlying file\n"
+ "descriptor. If the port is in non-blocking mode and\n"
+ "buffered characters can not be flushed immediately, then an\n"
+ "@code{EAGAIN} system-error exception will be raised (Note:\n"
+ "scsh does not support the use of non-blocking buffered ports.)\n"
+ "@item\n"
+ "write fewer than the requested number of\n"
+ "characters in some cases, e.g., if interrupted by a signal or\n"
+ "if not all of the output can be accepted immediately.\n"
+ "@item\n"
+ "wait indefinitely for at least one character\n"
+ "from @var{str} to be accepted by the port, unless the port is\n"
+ "in non-blocking mode.\n"
+ "@item\n"
+ "return the number of characters accepted by the port.\n"
+ "@item\n"
+ "return 0 if the port is in non-blocking mode and can not accept\n"
+ "at least one character from @var{str} immediately\n"
+ "@item\n"
+ "return 0 immediately if the request size is 0 bytes.\n"
+ "@end itemize")
+#define FUNC_NAME s_scm_write_string_partial
+{
+ const char *src;
+ long write_len;
+ int fdes;
+
+ {
+ size_t offset;
+ size_t last;
+
+ SCM_VALIDATE_STRING (1, str);
+ src = scm_i_string_chars (str);
+ scm_i_get_substring_spec (scm_i_string_length (str),
+ start, &offset, end, &last);
+ src += offset;
+ write_len = last - offset;
+ }
+
+ if (write_len == 0)
+ return SCM_INUM0;
+
+ if (scm_is_integer (port_or_fdes))
+ fdes = scm_to_int (port_or_fdes);
+ else
+ {
+ SCM port = (SCM_UNBNDP (port_or_fdes)?
+ scm_current_output_port () : port_or_fdes);
+ scm_t_port *pt;
+ off_t space;
+
+ SCM_VALIDATE_OPFPORT (2, port);
+ SCM_VALIDATE_OUTPUT_PORT (2, port);
+ pt = SCM_PTAB_ENTRY (port);
+ /* filling the last character in the buffer would require a flush. */
+ space = pt->write_end - pt->write_pos - 1;
+ if (space >= write_len)
+ {
+ memcpy (pt->write_pos, src, write_len);
+ pt->write_pos += write_len;
+ return scm_from_long (write_len);
+ }
+ if (pt->write_pos > pt->write_buf)
+ scm_flush (port);
+ fdes = SCM_FPORT_FDES (port);
+ }
+ {
+ long rv;
+
+ SCM_SYSCALL (rv = write (fdes, src, write_len));
+ if (rv == -1)
+ {
+ if (SCM_EBLOCK (errno))
+ rv = 0;
+ else
+ SCM_SYSERROR;
+ }
+
+ scm_remember_upto_here_1 (str);
+ return scm_from_long (rv);
+ }
+}
+#undef FUNC_NAME
+
+SCM
+scm_init_rw_builtins ()
+{
+#include "libguile/rw.x"
+
+ return SCM_UNSPECIFIED;
+}
+
+void
+scm_init_rw ()
+{
+ scm_c_define_gsubr ("%init-rw-builtins", 0, 0, 0, scm_init_rw_builtins);
+}
+
+/*
+ Local Variables:
+ c-file-style: "gnu"
+ End:
+*/
projects / lilypond.git / blobdiff