01-getnline.diff (was Re: [Bug-gnulib] getline & getline_safe)

[Derek Robert Price]

Paul Eggert wrote:

> Derek Robert Price <derek@ximbiot.com> writes:
>  
>
> > Incidentally, this implies having a getnline.c file which is always
> > compiled, and possibly which getline.c is dependent on.  Is this
> > reasonable?
> >    
> Sounds reasonable to me.
>  
>
> > The long run alternative is to get getndelim() & getnline() into
> > libc.  I haven't really dealt with libc before.  Is _this_
> > reasonable?  Is this likely?
> >    
> Maybe, maybe not.  Let's try gnulib first.  If only CVS uses it, then
> perhaps it's not worth worrying about for libc.
>  

Okay, here's my first pass.  It configures, builds, and passes `make 
check' with CVS, so I updated modules/getline, created modules/getnline, 
and am resubmitting to bug-gnulib.  Please let me know what you think.

I call it a first pass only because I wasn't sure how to document this 
complex dependency.  I think what I did was acceptable, but notice that 
I duplicated the getnline.* stuff between the two module descriptions.  
The basic difference is that if you want getline compiled conditionally 
but getnline compiled unconditionally then you add a call to 
gl_PREREQ_GETNLINE to configure.ac.  This is what I did with CVS.  If 
you just include the info as per the modules/getline file, getnline.c 
will only be compiled when it is needed for getline.c.

I still need to write the ChangeLog for CVS but I should commit these 
changes there soon.

Incidentally, my glibc defines both getdelim & getline to return 
ssize_t.  Is it intentional that the GNULIB versions return int instead?

        * lib/getnline.c: New file.
        * lib/getnline.h: Ditto.
        * m4/getnline.m4: Ditto.
        * modules/getnline: Ditto.

        * lib/getline.c: Move some include cruft with getdelim2 below.
        (getdelim2): Move to the new getnline.c above.
        (getdelim, getline): Wrap getndelim & getnline, respectitvely.
        * lib/getline.h: Use HAVE_WORKING_GETLINE & HAVE_GETDELIM rather than
        __GLIBC__ < 2, as per the autoconf paradigm.
        * m4/getline.m4 (AM_FUNC_GETLINE): Define HAVE_WORKING_GETLINE when
        appropriate.
        (gl_PREREQ_GETLINE): Call gl_PREREQ_GETNLINE when getdelim is not
        found.
        * modules/getline: Add new files to module setup instructions.


Index: lib/getline.c
===================================================================
RCS file: /cvsroot/gnulib/gnulib/lib/getline.c,v
retrieving revision 1.12
diff -u -r1.12 getline.c
--- lib/getline.c       4 Jun 2003 19:22:29 -0000       1.12
+++ lib/getline.c       16 Jul 2003 19:50:47 -0000
@@ -17,7 +17,9 @@
   along with this program; if not, write to the Free Software Foundation,
   Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */

-/* Written by Jan Brittenson, bson@gnu.ai.mit.edu.  */
+/* Adapted by Derek Price <derek@ximbiot.com>
+ * from getline.c written by Jan Brittenson <bson@gnu.ai.mit.edu>.
+ */

#if HAVE_CONFIG_H
# include <config.h>
@@ -44,105 +46,18 @@

#else /* ! have getdelim */

-# if STDC_HEADERS
-#  include <stdlib.h>
-# else
-char *malloc (), *realloc ();
-# endif
-
-#include "unlocked-io.h"
-
-/* Always add at least this many bytes when extending the buffer.  */
-#define MIN_CHUNK 64
-
-/* Read up to (and including) a delimiter DELIM1 from STREAM into *LINEPTR
-   + OFFSET (and NUL-terminate it).  If DELIM2 is non-zero, then read up
-   and including the first occurrence of DELIM1 or DELIM2.  *LINEPTR is
-   a pointer returned from malloc (or NULL), pointing to *N characters of
-   space.  It is realloc'd as necessary.  Return the number of characters
-   read (not including the NUL terminator), or -1 on error or EOF.  */
-
-static int
-getdelim2 (char **lineptr, size_t *n, FILE *stream, int delim1, int delim2,
-          size_t offset)
-{
-  size_t nchars_avail;         /* Allocated but unused chars in *LINEPTR.  */
-  char *read_pos;              /* Where we're reading into *LINEPTR. */
-  int ret;
-
-  if (!lineptr || !n || !stream)
-    return -1;
-
-  if (!*lineptr)
-    {
-      *n = MIN_CHUNK;
-      *lineptr = malloc (*n);
-      if (!*lineptr)
-       return -1;
-    }
-
-  if (*n < offset)
-    return -1;
-
-  nchars_avail = *n - offset;
-  read_pos = *lineptr + offset;
-
-  for (;;)
-    {
-      register int c = getc (stream);
-
-      /* We always want at least one char left in the buffer, since we
-        always (unless we get an error while reading the first char)
-        NUL-terminate the line buffer.  */
-
-      if (nchars_avail < 2)
-       {
-         if (*n > MIN_CHUNK)
-           *n *= 2;
-         else
-           *n += MIN_CHUNK;
-
-         nchars_avail = *n + *lineptr - read_pos;
-         *lineptr = realloc (*lineptr, *n);
-         if (!*lineptr)
-           return -1;
-         read_pos = *n - nchars_avail + *lineptr;
-       }
-
-      if (c == EOF || ferror (stream))
-       {
-         /* Return partial line, if any.  */
-         if (read_pos == *lineptr)
-           return -1;
-         else
-           break;
-       }
-
-      *read_pos++ = c;
-      nchars_avail--;
-
-      if (c == delim1 || (delim2 && c == delim2))
-       /* Return the line.  */
-       break;
-    }
-
-  /* Done - NUL terminate and return the number of chars read.  */
-  *read_pos = '\0';
-
-  ret = read_pos - (*lineptr + offset);
-  return ret;
-}
-
+# include "getnline.h"
+# include "unlocked-io.h"

int
getline (char **lineptr, size_t *n, FILE *stream)
{
-  return getdelim2 (lineptr, n, stream, '\n', 0, 0);
+  return getnline (lineptr, n, stream, GETNDELIM_NO_LIMIT);
}

int
getdelim (char **lineptr, size_t *n, int delimiter, FILE *stream)
{
-  return getdelim2 (lineptr, n, stream, delimiter, 0, 0);
+  return getndelim (lineptr, n, delimiter, stream, GETNDELIM_NO_LIMIT);
}
-#endif
+#endif /* have getdelim */
Index: lib/getline.h
===================================================================
RCS file: /cvsroot/gnulib/gnulib/lib/getline.h,v
retrieving revision 1.12
diff -u -r1.12 getline.h
--- lib/getline.h       18 Jun 2003 05:52:19 -0000      1.12
+++ lib/getline.h       16 Jul 2003 19:50:47 -0000
@@ -24,12 +24,16 @@
# include <stdio.h>

/* glibc2 has these functions declared in <stdio.h>.  Avoid redeclarations.  */
-# if __GLIBC__ < 2
+# if !HAVE_WORKING_GETLINE

int getline (char **_lineptr, size_t *_n, FILE *_stream);

+# endif /* ! have getline */
+
+# if !HAVE_GETDELIM
+
int getdelim (char **_lineptr, size_t *_n, int _delimiter, FILE *_stream);

-# endif
+# endif /* ! have getdelim */

#endif /* not GETLINE_H_ */
Index: lib/getnline.c
===================================================================
RCS file: lib/getnline.c
diff -N lib/getnline.c
--- /dev/null   1 Jan 1970 00:00:00 -0000
+++ lib/getnline.c      16 Jul 2003 19:50:47 -0000
@@ -0,0 +1,143 @@
+/* getnline.c -- Implementation of getnline function, a modification of
+   the GNU C library function getline to allow the caller to set a
+   maximum number of characters to be retrieved.
+
+   Copyright (C) 1993, 1996, 1997, 1998, 2000, 2003 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
+   the Free Software Foundation; either version 2, 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.  */
+
+/* Adapted by Derek Price <derek@ximbiot.com>
+ * from getline.c written by Jan Brittenson <bson@gnu.ai.mit.edu>.
+ */
+
+#if HAVE_CONFIG_H
+# include <config.h>
+#endif
+
+#include "getnline.h"
+
+#include <stddef.h>
+#include <stdio.h>
+
+#if STDC_HEADERS
+# include <stdlib.h>
+#else
+char *malloc (), *realloc ();
+#endif
+
+#include "unlocked-io.h"
+
+/* Always add at least this many bytes when extending the buffer.  */
+#define MIN_CHUNK 64
+
+/* Read up to (and including) a delimiter DELIM1 from STREAM into *LINEPTR
+   + OFFSET (and NUL-terminate it).  If DELIM2 is non-zero, then read up
+   and including the first occurrence of DELIM1 or DELIM2.  *LINEPTR is
+   a pointer returned from malloc (or NULL), pointing to *N characters of
+   space.  It is realloc'd as necessary.  Return the number of characters
+   read (not including the NUL terminator), or -1 on error or EOF.  */
+
+static int
+getdelim2( char **lineptr, size_t *n, size_t offset, int limit,
+           int delim1, int delim2, FILE *stream )
+{
+  size_t nchars_avail;         /* Allocated but unused chars in *LINEPTR.  */
+  char *read_pos;              /* Where we're reading into *LINEPTR. */
+  int ret;
+
+  if (!lineptr || !n || !stream)
+    return -1;
+
+  if (!*lineptr)
+    {
+      *n = MIN_CHUNK;
+      *lineptr = malloc (*n);
+      if (!*lineptr)
+       return -1;
+    }
+
+  if (*n < offset)
+    return -1;
+
+  nchars_avail = *n - offset;
+  read_pos = *lineptr + offset;
+
+  for (;;)
+    {
+      register int c;
+
+      if (limit == 0)
+       break;
+
+      c = getc (stream);
+
+      if (limit != GETNLINE_NO_LIMIT)
+       limit--;
+
+      /* We always want at least one char left in the buffer, since we
+        always (unless we get an error while reading the first char)
+        NUL-terminate the line buffer.  */
+
+      if (nchars_avail < 2)
+       {
+         if (*n > MIN_CHUNK)
+           *n *= 2;
+         else
+           *n += MIN_CHUNK;
+
+         nchars_avail = *n + *lineptr - read_pos;
+         *lineptr = realloc (*lineptr, *n);
+         if (!*lineptr)
+           return -1;
+         read_pos = *n - nchars_avail + *lineptr;
+       }
+
+      if (c == EOF || ferror (stream))
+       {
+         /* Return partial line, if any.  */
+         if (read_pos == *lineptr)
+           return -1;
+         else
+           break;
+       }
+
+      *read_pos++ = c;
+      nchars_avail--;
+
+      if (c == delim1 || (delim2 && c == delim2))
+       /* Return the line.  */
+       break;
+    }
+
+  /* Done - NUL terminate and return the number of chars read.  */
+  *read_pos = '\0';
+
+  ret = read_pos - (*lineptr + offset);
+  return ret;
+}
+
+
+int
+getnline( char **lineptr, size_t *n, int limit, FILE *stream )
+{
+  return getdelim2( lineptr, n, 0, limit, '\n', 0, stream );
+}
+
+int
+getndelim( char **lineptr, size_t *n, int limit, int delimiter, FILE *stream )
+{
+  return getdelim2( lineptr, n, 0, limit, delimiter, 0, stream );
+}
Index: lib/getnline.h
===================================================================
RCS file: lib/getnline.h
diff -N lib/getnline.h
--- /dev/null   1 Jan 1970 00:00:00 -0000
+++ lib/getnline.h      16 Jul 2003 19:50:47 -0000
@@ -0,0 +1,35 @@
+/* Implementation of getnline function, a version of the GNU C library
+   function getline which allows a maximum number of characters retrieved
+   to be set.
+
+   Copyright (C) 1995, 1997, 1999, 2000, 2001, 2002, 2003 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
+the Free Software Foundation; either version 2, 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.  */
+
+#ifndef GETNLINE_H_
+# define GETNLINE_H_ 1
+
+# include <stddef.h>
+# include <stdio.h>
+
+# define GETNLINE_NO_LIMIT -1
+
+int getnline( char **_lineptr, size_t *_n, int limit, FILE *_stream );
+
+int getndelim( char **_lineptr, size_t *_n, int limit, int _delimiter,
+               FILE *_stream );
+
+#endif /* not GETNLINE_H_ */
Index: m4/getline.m4
===================================================================
RCS file: /cvsroot/gnulib/gnulib/m4/getline.m4,v
retrieving revision 1.11
diff -u -r1.11 getline.m4
--- m4/getline.m4       13 Jan 2003 07:08:00 -0000      1.11
+++ m4/getline.m4       16 Jul 2003 19:50:48 -0000
@@ -1,4 +1,4 @@
-# getline.m4 serial 8
+# getline.m4 serial 9

dnl Copyright (C) 1998, 1999, 2000, 2001, 2002, 2003 Free Software
dnl Foundation, Inc.
@@ -22,9 +22,9 @@

  am_getline_needs_run_time_check=no
  AC_CHECK_FUNC(getline,
-               dnl Found it in some library.  Verify that it works.
-               am_getline_needs_run_time_check=yes,
-               am_cv_func_working_getline=no)
+                dnl Found it in some library.  Verify that it works.
+                am_getline_needs_run_time_check=yes,
+                am_cv_func_working_getline=no)
  if test $am_getline_needs_run_time_check = yes; then
    AC_CACHE_CHECK([for working getline function], am_cv_func_working_getline,
    [echo fooN |tr -d '\012'|tr N '\012' > conftest.data
@@ -49,7 +49,10 @@
    )])
  fi

-  if test $am_cv_func_working_getline = no; then
+  if test $am_cv_func_working_getline = yes; then
+    AC_DEFINE([HAVE_WORKING_GETLINE], [1],
+      [Define to 1 if your system has a working GNU getline() function.])
+  else
    dnl We must choose a different name for our function, since on ELF systems
    dnl a broken getline() in libc.so would override our getline() in
    dnl libgettextlib.so.
@@ -63,6 +66,11 @@
# Prerequisites of lib/getline.c.
AC_DEFUN([gl_PREREQ_GETLINE],
[
-  AC_REQUIRE([AC_HEADER_STDC])
-  AC_CHECK_FUNCS(getdelim)
+  AC_CHECK_FUNCS(getdelim,
+                 dnl found it.
+                 gl_have_getdelim=yes,
+                 gl_have_getdelim=no)
+  if test $gl_have_getdelim = no; then
+    gl_PREREQ_GETNLINE
+  fi
])
Index: m4/getnline.m4
===================================================================
RCS file: m4/getnline.m4
diff -N m4/getnline.m4
--- /dev/null   1 Jan 1970 00:00:00 -0000
+++ m4/getnline.m4      16 Jul 2003 19:50:48 -0000
@@ -0,0 +1,16 @@
+# getnline.m4 serial 1
+
+dnl Copyright (C) 2003 Free Software Foundation, Inc.
+
+dnl This file is free software, distributed under the terms of the GNU
+dnl General Public License.  As a special exception to the GNU General
+dnl Public License, this file may be distributed as part of a program
+dnl that contains a configuration script generated by Autoconf, under
+dnl the same distribution terms as the rest of that program.
+
+# Prerequisites of lib/getnline.c.
+AC_DEFUN([gl_PREREQ_GETNLINE],
+[
+  AC_REQUIRE([AC_HEADER_STDC])
+  AC_LIBOBJ(getnline)
+])
Index: modules/getline
===================================================================
RCS file: /cvsroot/gnulib/gnulib/modules/getline,v
retrieving revision 1.4
diff -u -r1.4 getline
--- modules/getline     20 Jan 2003 10:02:37 -0000      1.4
+++ modules/getline     16 Jul 2003 19:50:48 -0000
@@ -4,7 +4,10 @@
Files:
lib/getline.h
lib/getline.c
+lib/getnline.h
+lib/getnline.c
m4/getline.m4
+m4/getnline.m4

Depends-on:
unlocked-io
@@ -13,7 +16,7 @@
AM_FUNC_GETLINE

Makefile.am:
-lib_SOURCES += getline.h
+lib_SOURCES += getline.h getnline.h

Include:
"getline.h"
Index: modules/getnline
===================================================================
RCS file: modules/getnline
diff -N modules/getnline
--- /dev/null   1 Jan 1970 00:00:00 -0000
+++ modules/getnline    16 Jul 2003 19:50:48 -0000
@@ -0,0 +1,23 @@
+Description:
+Read a line of n characters or less from a stream.
+
+Files:
+lib/getnline.h
+lib/getnline.c
+m4/getnline.m4
+
+Depends-on:
+unlocked-io
+
+configure.ac:
+gl_PREREQ_GETNLINE
+
+Makefile.am:
+lib_SOURCES += getnline.h
+
+Include:
+"getnline.h"
+
+Maintainer:
+all
+



Derek

--
               *8^)

Email: derek@ximbiot.com

Get CVS support at <http://ximbiot.com>!
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