initial version of code to read lines from a string.

src/include/ZMap/zmapReadLine.h

+/*  File: zmapReadLine.h
+ *  Author: Ed Griffiths (edgrif@sanger.ac.uk)
+ *  Copyright (c) Sanger Institute, 2004
+ *-------------------------------------------------------------------
+ * ZMap is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ * 
+ * This program 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 General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
+ * or see the on-line version at http://www.gnu.org/copyleft/gpl.txt
+ *-------------------------------------------------------------------
+ * This file is part of the ZMap genome database package
+ * originated by
+ * 	Ed Griffiths (Sanger Institute, UK) edgrif@sanger.ac.uk,
+ *      Rob Clack (Sanger Institute, UK) rnc@sanger.ac.uk
+ *
+ * Description: The interface to a line reading package.
+ * HISTORY:
+ * Last edited: Jun 25 09:53 2004 (edgrif)
+ * Created: Thu Jun 24 19:32:55 2004 (edgrif)
+ * CVS info:   $Id: zmapReadLine.h,v 1.1 2004-06-25 13:29:29 edgrif Exp $
+ *-------------------------------------------------------------------
+ */
+#ifndef ZMAP_READLINE_H
+#define ZMAP_READLINE_H
+
+
+#include <glib.h>
+
+
+/*! @addtogroup zmaputils
+ * @{
+ *  */
+
+
+/*!
+ * ZMapReadLine object containing the set of lines to be returned one at a time. */
+typedef struct _ZMapReadLineStruct *ZMapReadLine ;
+
+
+/*! @} end of zmaputils docs. */
+
+
+ZMapReadLine zMapReadLineCreate(char *lines, gboolean in_place) ;
+gboolean zMapReadLineNext(ZMapReadLine read_line, char **next_line_out) ;
+void zMapReadLineDestroy(ZMapReadLine read_line, gboolean free_string) ;
+
+#endif /* !ZMAP_READLINE_H */

src/zmapUtils/zmapReadLine.c

+/*  File: zmapReadLine.c
+ *  Author: Ed Griffiths (edgrif@sanger.ac.uk)
+ *  Copyright (c) Sanger Institute, 2004
+ *-------------------------------------------------------------------
+ * ZMap is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ * 
+ * This program 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 General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
+ * or see the on-line version at http://www.gnu.org/copyleft/gpl.txt
+ *-------------------------------------------------------------------
+ * This file is part of the ZMap genome database package
+ * originated by
+ * 	Ed Griffiths (Sanger Institute, UK) edgrif@sanger.ac.uk,
+ *      Rob Clack (Sanger Institute, UK) rnc@sanger.ac.uk
+ *
+ * Description: Package to read lines from a string, currently this
+ *              is done by altering the string, the code to do this
+ *              leaving the string unaltered and returning the next
+ *              line in a separate buffer is not currently implemented.
+ *              
+ * Exported functions: See ZMap/zmapReadLine.h
+ * HISTORY:
+ * Last edited: Jun 25 09:52 2004 (edgrif)
+ * Created: Thu Jun 24 19:03:50 2004 (edgrif)
+ * CVS info:   $Id: zmapReadLine.c,v 1.1 2004-06-25 13:30:25 edgrif Exp $
+ *-------------------------------------------------------------------
+ */
+
+#include <glib.h>
+#include <zmapReadLine_P.h>
+
+
+static gboolean inPlaceRead(ZMapReadLine read_line, char **next_line_out) ;
+
+/*! @addtogroup zmaputils
+ * @{
+ *  */
+
+
+/*!
+ * Create a ZMapReadLine object which can then be used to return each successive
+ * line in the input text by making repeated calls to zMapReadLineNext(). Lines
+ * must be demarcated in the usual C string manner by a '\n' character.
+ *
+ * @param input_lines A null terminated C string containing the lines to be parsed.
+ * @param in_place    If TRUE, lines will be returned by substituting the line terminator
+ *                    character '\n' with a string terminator '\0' and returning a pointer
+ *                    to the now null-terminated string.
+ *                    NOTE that in_place == TRUE is the only implemented option currently.
+ * @return            The new ZMapReadLine object.
+ *  */
+ZMapReadLine zMapReadLineCreate(char *input_lines, gboolean in_place)
+{
+  ZMapReadLine read_line ;
+
+  read_line = g_new(ZMapReadLineStruct, 1) ;
+
+  read_line->original = input_lines ;
+  read_line->current = read_line->next = NULL ;
+
+  read_line->in_place = in_place ;
+
+  return read_line ;
+}
+
+
+/*!
+ * Read the next line from a ZMapReadLine object. If a '\n' terminated line can
+ * be read the function returns TRUE and returns the line in next_line_out.
+ * If no terminating '\n' character could be found then the function returns
+ * FALSE and returns the remainging string in next_line_out. NOTE that this
+ * means that when there is no more string left the function will return
+ * FALSE and next_line_out will contain the null string "".
+ *
+ * @param read_line     The ZMapReadLine object from which the next line is to be read.
+ * @param next_line_out The next complete line or the remaining text in the string if it
+ *                      is not terminated with a '\n' or the empty string "" if there is
+ *                      no more text.
+ * @return              TRUE if a complete line could be returned, FALSE otherwise.
+ *  */
+gboolean zMapReadLineNext(ZMapReadLine read_line, char **next_line_out)
+{
+  gboolean result = FALSE ;
+  char *next_line = NULL ;
+
+  if (read_line->in_place)
+    {
+      result = inPlaceRead(read_line, &next_line) ;
+
+      *next_line_out = next_line ;
+    }
+  /* else do a buffer read..... */
+
+  return result ;
+}
+
+
+/*!
+ * Destroy the ZMapReadLine object and optionally free the original string.
+ *
+ * @param read_line     The ZMapReadLine object to be destroyed.
+ * @param free_string   If TRUE the original string used to create the
+ *                      ZMapReadLine object will be freed as well.
+ * @return              nothing.
+ *  */
+void zMapReadLineDestroy(ZMapReadLine read_line, gboolean free_string)
+{
+  if (free_string)
+    g_free(read_line->original) ;
+
+  g_free(read_line) ;
+
+  return ;
+}
+
+
+/*! @} end of zmaputils docs. */
+
+
+static gboolean inPlaceRead(ZMapReadLine read_line, char **next_line_out)
+{
+  gboolean result = FALSE ;
+  char *curr ;
+
+  if (!read_line->current)
+    {
+      read_line->current = read_line->original ;
+    }
+  else
+    read_line->current = read_line->next ;
+
+  curr = read_line->current ;
+  while (*curr && *curr != '\n')
+    {
+      curr++ ;
+    }
+
+
+  if (*curr == '\n')
+    {
+      read_line->next = curr + 1 ;
+      *curr = '\0' ;
+      result = TRUE ;
+    }
+  else							    /* curr = '\0' */
+    {
+      /* no end of line before end of string. */
+      read_line->next = curr ;
+      result = FALSE ;
+    }
+
+  *next_line_out = read_line->current ;
+
+  return result ;
+}
+

src/zmapUtils/zmapReadLine_P.h

+/*  File: zmapReadLine_P.h
+ *  Author: Ed Griffiths (edgrif@sanger.ac.uk)
+ *  Copyright (c) Sanger Institute, 2004
+ *-------------------------------------------------------------------
+ * ZMap is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ * 
+ * This program 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 General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
+ * or see the on-line version at http://www.gnu.org/copyleft/gpl.txt
+ *-------------------------------------------------------------------
+ * This file is part of the ZMap genome database package
+ * originated by
+ * 	Ed Griffiths (Sanger Institute, UK) edgrif@sanger.ac.uk,
+ *      Rob Clack (Sanger Institute, UK) rnc@sanger.ac.uk
+ *
+ * Description: Internal data structs for the line reading package.
+ * HISTORY:
+ * Last edited: Jun 25 10:05 2004 (edgrif)
+ * Created: Thu Jun 24 19:33:38 2004 (edgrif)
+ * CVS info:   $Id: zmapReadLine_P.h,v 1.1 2004-06-25 13:30:25 edgrif Exp $
+ *-------------------------------------------------------------------
+ */
+
+#ifndef ZMAP_READLINE_p_h
+#define ZMAP_READLINE_p_h
+
+
+#include <glib.h>
+#include <ZMap/zmapReadLine.h>
+
+
+/* Represents a single C string from which to return successive lines. */
+typedef struct _ZMapReadLineStruct
+{
+  char *original ;					    /* The original string. */
+  char *current ;					    /* The current string which is
+							       returned by zMapReadLineNext(). */
+  char *next ;						    /* The string following the current
+							       string. */
+
+  gboolean in_place ;					    /* TRUE => return strings operating on
+							       the original string and returning
+							       pointers to substrings within it.*/
+} ZMapReadLineStruct ;
+
+
+#endif /* !ZMAP_READLINE_p_h */
+