ports.c, ports.h (scm_c_read, scm_c_write): New functions.

ports.h (SCM_READ_BUFFER_EMPTY_P): New macro.

NEWS

@@ -1,5 +1,5 @@
 Guile NEWS --- history of user-visible changes.  -*- text -*-
-Copyright (C) 1996, 1997, 1998, 1999, 2000 Free Software Foundation, Inc.
+Copyright (C) 1996, 1997, 1998, 1999, 2000, 2001 Free Software Foundation, Inc.
 See the end for copying conditions.
 
 Please send Guile bug reports to bug-guile@gnu.org.
@@ -372,6 +372,23 @@ There is no such concept as a weak binding any more.
 
 * Changes to the scm_ interface
 
+** New function: scm_c_read (SCM port, void *buffer, scm_sizet size)
+
+Used by an application to read arbitrary number of bytes from a port.
+Same semantics as libc read, except that scm_c_read only returns less
+than SIZE bytes if at end-of-file.
+
+Warning: Doesn't update port line and column counts!
+
+** New function: scm_c_write (SCM port, const void *ptr, scm_sizet size)
+
+Used by an application to write arbitrary number of bytes to an SCM
+port.  Similar semantics as libc write.  However, unlike libc
+write, scm_c_write writes the requested number of bytes and has no
+return value.
+
+Warning: Doesn't update port line and column counts!
+
 ** New function: scm_init_guile ()
 
 In contrast to scm_boot_guile, scm_init_guile will return normally

libguile/ChangeLog

@@ -1,3 +1,9 @@
+2001-02-23  Mikael Djurfeldt  <mdj@linnaeus.mit.edu>
+
+	* ports.c, ports.h (scm_c_read, scm_c_write): New functions.
+
+	* ports.h (SCM_READ_BUFFER_EMPTY_P): New macro.
+
 2001-02-24  Neil Jerram  <neil@ossau.uklinux.net>
 
 	* numbers.c (scm_two_doubles, scm_sys_expt, scm_sys_atan2,

libguile/ports.c

@@ -1,4 +1,4 @@
-/*	Copyright (C) 1995,1996,1997,1998,1999, 2000 Free Software Foundation, Inc.
+/*	Copyright (C) 1995,1996,1997,1998,1999, 2000, 2001 Free Software Foundation, Inc.
  * 
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -963,6 +963,14 @@ scm_puts (const char *s, SCM port)
   scm_lfwrite (s, strlen (s), port);
 }
 
+/* scm_lfwrite
+ *
+ * Currently, this function has an identical implementation to
+ * scm_c_write.  We could have turned it into a macro expanding into a
+ * call to scm_c_write.  However, the implementation is small and
+ * might differ in the future.
+ */
+
 void 
 scm_lfwrite (const char *ptr, scm_sizet size, SCM port)
 {
@@ -978,6 +986,81 @@ scm_lfwrite (const char *ptr, scm_sizet size, SCM port)
     pt->rw_active = SCM_PORT_WRITE;
 }
 
+/* scm_c_read
+ *
+ * Used by an application to read arbitrary number of bytes from an
+ * SCM port.  Same semantics as libc read, except that scm_c_read only
+ * returns less than SIZE bytes if at end-of-file.
+ *
+ * Warning: Doesn't update port line and column counts!  */
+
+scm_sizet
+scm_c_read (SCM port, void *buffer, scm_sizet size)
+{
+  scm_port *pt = SCM_PTAB_ENTRY (port);
+  scm_sizet n_read = 0, n_available;
+
+  if (pt->rw_active == SCM_PORT_WRITE)
+    scm_ptobs[SCM_PTOBNUM (port)].flush (port);
+
+  if (pt->rw_random)
+    pt->rw_active = SCM_PORT_READ;
+
+  if (SCM_READ_BUFFER_EMPTY_P (pt))
+    {
+      if (scm_fill_input (port) == EOF)
+	return 0;
+    }
+  
+  n_available = pt->read_end - pt->read_pos;
+  
+  while (n_available < size)
+    {
+      memcpy (buffer, pt->read_pos, n_available);
+      buffer += n_available;
+      pt->read_pos += n_available;
+      n_read += n_available;
+      
+      if (SCM_READ_BUFFER_EMPTY_P (pt))
+	{
+	  if (scm_fill_input (port) == EOF)
+	    return n_read;
+	}
+
+      size -= n_available;
+      n_available = pt->read_end - pt->read_pos;
+    }
+
+  memcpy (buffer, pt->read_pos, size);
+  pt->read_pos += size;
+
+  return n_read + size;
+}
+
+/* scm_c_write
+ *
+ * Used by an application to write arbitrary number of bytes to an SCM
+ * port.  Similar semantics as libc write.  However, unlike libc
+ * write, scm_c_write writes the requested number of bytes and has no
+ * return value.
+ *
+ * Warning: Doesn't update port line and column counts!
+ */
+
+void 
+scm_c_write (SCM port, const void *ptr, scm_sizet size)
+{
+  scm_port *pt = SCM_PTAB_ENTRY (port);
+  scm_ptob_descriptor *ptob = &scm_ptobs[SCM_PTOBNUM (port)];
+
+  if (pt->rw_active == SCM_PORT_READ)
+    scm_end_input (port);
+
+  ptob->write (port, ptr, size);
+
+  if (pt->rw_random)
+    pt->rw_active = SCM_PORT_WRITE;
+}
 
 void 
 scm_flush (SCM port)
@@ -1199,8 +1282,8 @@ SCM_DEFINE (scm_seek, "seek", 3, 0, 0,
 
   object = SCM_COERCE_OUTPORT (object);
 
-  off = SCM_NUM2LONG (2,offset);
+  off = SCM_NUM2LONG (2, offset);
-  SCM_VALIDATE_INUM_COPY (3,whence,how);
+  SCM_VALIDATE_INUM_COPY (3, whence, how);
   if (how != SEEK_SET && how != SEEK_CUR && how != SEEK_END)
     SCM_OUT_OF_RANGE (3, whence);
   if (SCM_OPPORTP (object))

libguile/ports.h

@@ -2,7 +2,7 @@
 
 #ifndef PORTSH
 #define PORTSH
-/*	Copyright (C) 1995,1996,1997,1998,1999, 2000 Free Software Foundation, Inc.
+/*	Copyright (C) 1995,1996,1997,1998,1999, 2000, 2001 Free Software Foundation, Inc.
  * 
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -135,6 +135,7 @@ typedef struct
 extern scm_port **scm_port_table;
 extern int scm_port_table_size; /* Number of ports in scm_port_table.  */
 
+#define SCM_READ_BUFFER_EMPTY_P(c_port) (c_port->read_pos >= c_port->read_end)
 
 
 
@@ -279,6 +280,8 @@ extern SCM scm_flush_all_ports (void);
 extern SCM scm_read_char (SCM port);
 extern void scm_putc (char c, SCM port);
 extern void scm_puts (const char *str_data, SCM port);
+extern scm_sizet scm_c_read (SCM port, void *buffer, scm_sizet size);
+extern void scm_c_write (SCM port, const void *buffer, scm_sizet size);
 extern void scm_lfwrite (const char *ptr, scm_sizet size, SCM port);
 extern void scm_flush (SCM port);
 extern void scm_end_input (SCM port);