Re: PATCH[libiberty] for Re: Mainline: C++ include files not found!

Re: PATCH[libiberty] for Re: Mainline: C++ include files not found!

[Daniel Jacobowitz]

On Thu, Feb 20, 2003 at 03:26:46PM -0500, DJ Delorie wrote:
> 
> For libiberty-only patches, please cc the gdb and binutils mailing
> lists as well.
> 
> Note that DJGPP has a function similar to realpath called "_truename":
> 
> http://www.delorie.com/djgpp/doc/libc/libc_776.html
> 
> But I don't think it would make any difference in this case, since
> djgpp doesn't support symlinked directories.  DJGPP *does* support
> readlink() though (.exe's are allowed to be symlinks, we fake it).  It
> would be nice if the fall-through case at least tried readlink() (if
> available).

My initial reluctance was that readlink isn't guaranteed to give us
something that we can append to the dirname and access.  And I'd need
to drag in both stat and readlink, and some bits for
HOST_EXECUTABLE_SUFFIX that I'm not entirely sure of.  Would you rather
I add this, or can we leave it until someone needs this on DJGPP?

> Case 2a will never happen - we can't guarantee the ability to run that
> configure test.

I'll just delete it.

> Note that I'm not a big fan of libiberty itself using the xmalloc
> functions.  Doing so automatically precludes using those functions
> (that use xmalloc) in bfd (at least, maybe gdb also) because an
> uncontrolled exit is undesirable, and/or the use of printf may be
> problematic.  If it were up to me (and I'm willing to let this one
> slide) I'd have the return value be defined as:
> 
> 	1. The same pointer as "filename" (i.e. no malloc), or
> 	2. A NULL pointer (i.e. error), or
> 	3. Some other pointer (malloc'd, must be free'd)
> 
> Doing the malloc "just because" seems wasteful to me.

Optionally returning filename seems risky to me, personally.  I'd go
for just 2+3 and return NULL if we don't get a result; but I like the
simplicity of this interface as it is.

You've got a good point on the xmalloc thing.  How about use malloc and
return NULL on allocation failure?  And strdup instead of xstrdup.

> For libiberty_NEED_DECLARATION, you need to include "confdefs.h" or
> you won't get any of the HAVE_ macros.

Oh, that's cute.  I copied this function from BFD, which has the same
problem.  Fixed.

-- 
Daniel Jacobowitz
MontaVista Software                         Debian GNU/Linux Developer

Re: PATCH[libiberty] for Re: Mainline: C++ include files not found!

[DJ Delorie]

> My initial reluctance was that readlink isn't guaranteed to give us
> something that we can append to the dirname and access.  And I'd
> need to drag in both stat and readlink, and some bits for
> HOST_EXECUTABLE_SUFFIX that I'm not entirely sure of.

I had at one point written a semi-portable canonicalize_file_name()
that did all that, but the reason I wrote it went away, so I dropped
it.

> Would you rather I add this, or can we leave it until someone needs
> this on DJGPP?

It will work well enough on DJGPP without it, so I wouldn't bother.

> Optionally returning filename seems risky to me, personally.

I'm thinking that most uses of this function will call it once at
program startup and not even need to free the malloc'd pointer.  I
guess it doesn't matter either way.

> You've got a good point on the xmalloc thing.  How about use malloc
> and return NULL on allocation failure?  And strdup instead of
> xstrdup.

That would be better.

Re: PATCH[libiberty] for Re: Mainline: C++ include files not found!

[Daniel Jacobowitz]

On Thu, Feb 20, 2003 at 04:12:47PM -0500, DJ Delorie wrote:
> 
> > My initial reluctance was that readlink isn't guaranteed to give us
> > something that we can append to the dirname and access.  And I'd
> > need to drag in both stat and readlink, and some bits for
> > HOST_EXECUTABLE_SUFFIX that I'm not entirely sure of.
> 
> I had at one point written a semi-portable canonicalize_file_name()
> that did all that, but the reason I wrote it went away, so I dropped
> it.
> 
> > Would you rather I add this, or can we leave it until someone needs
> > this on DJGPP?
> 
> It will work well enough on DJGPP without it, so I wouldn't bother.
> 
> > Optionally returning filename seems risky to me, personally.
> 
> I'm thinking that most uses of this function will call it once at
> program startup and not even need to free the malloc'd pointer.  I
> guess it doesn't matter either way.

make_relative_prefix actually wants to free it.

> > You've got a good point on the xmalloc thing.  How about use malloc
> > and return NULL on allocation failure?  And strdup instead of
> > xstrdup.
> 
> That would be better.

Here it is with cleanups.

-- 
Daniel Jacobowitz
MontaVista Software                         Debian GNU/Linux Developer

2003-02-20  Daniel Jacobowitz  <drow@mvista.com>

	* libiberty.h (lrealpath): Add declaration.

2003-02-20  Daniel Jacobowitz  <drow@mvista.com>

	* Makefile.in (CFILES): Add lrealpath.c.
	(REQUIRED_OFILES): Add lrealpath.o.
	(lrealpath.o): Add rule.
	* aclocal.m4 (libiberty_NEED_DECLARATION): Add.
	* configure.in: Add realpath and canonicalize_file_name to
	checkfuncs and AC_CHECK_FUNCS.  Use libiberty_NEED_DECLARATION
	for canonicalize_file_name.
	* lrealpath.c: New file.
	* make-relative-prefix.c: Update documentation.
	(make_relative_prefix): Simplify.  Use lbasename and lrealpath.
	* config.in: Regenerated.
	* configure: Regenerated.
	* functions.texi: Regenerated.

Index: include/libiberty.h
===================================================================
RCS file: /big/fsf/rsync/gcc-cvs/gcc/include/libiberty.h,v
retrieving revision 1.31
diff -u -p -r1.31 libiberty.h
--- include/libiberty.h	24 Nov 2002 06:54:38 -0000	1.31
+++ include/libiberty.h	20 Feb 2003 16:46:16 -0000
@@ -85,6 +85,10 @@ extern char *basename ();
 
 extern const char *lbasename PARAMS ((const char *));
 
+/* A well-defined realpath () that is always compiled in.  */
+
+extern char *lrealpath PARAMS ((const char *));
+
 /* Concatenate an arbitrary number of strings.  You must pass NULL as
    the last argument of this function, to terminate the list of
    strings.  Allocates memory using xmalloc.  */
Index: libiberty/Makefile.in
===================================================================
RCS file: /big/fsf/rsync/gcc-cvs/gcc/libiberty/Makefile.in,v
retrieving revision 1.85
diff -u -p -r1.85 Makefile.in
--- libiberty/Makefile.in	30 Jan 2003 19:02:11 -0000	1.85
+++ libiberty/Makefile.in	20 Feb 2003 17:21:34 -0000
@@ -137,6 +137,7 @@ CFILES = alloca.c argv.c asprintf.c atex
 	hashtab.c hex.c							\
 	index.c insque.c						\
 	lbasename.c							\
+	lrealpath.c							\
 	make-relative-prefix.c						\
 	make-temp-file.c md5.c memchr.c memcmp.c memcpy.c memmove.c	\
 	 memset.c mkstemps.c						\
@@ -165,6 +166,7 @@ REQUIRED_OFILES = regex.o cplus-dem.o cp
 	getopt.o getopt1.o getpwd.o getruntime.o			\
 	hashtab.o hex.o							\
 	lbasename.o							\
+	lrealpath.o							\
 	make-relative-prefix.o						\
 	make-temp-file.o						\
 	objalloc.o obstack.o						\
@@ -443,6 +445,7 @@ hashtab.o: config.h $(INCDIR)/ansidecl.h
 hex.o: $(INCDIR)/ansidecl.h $(INCDIR)/libiberty.h
 lbasename.o: $(INCDIR)/ansidecl.h $(INCDIR)/libiberty.h \
 	$(INCDIR)/safe-ctype.h
+lrealpath.o: config.h $(INCDIR)/ansidecl.h $(INCDIR)/libiberty.h
 make-relative-prefix.o: config.h $(INCDIR)/ansidecl.h $(INCDIR)/libiberty.h
 make-temp-file.o: config.h $(INCDIR)/ansidecl.h $(INCDIR)/libiberty.h
 md5.o: config.h $(INCDIR)/ansidecl.h $(INCDIR)/md5.h
Index: libiberty/aclocal.m4
===================================================================
RCS file: /big/fsf/rsync/gcc-cvs/gcc/libiberty/aclocal.m4,v
retrieving revision 1.5
diff -u -p -r1.5 aclocal.m4
--- libiberty/aclocal.m4	31 Dec 2001 23:23:49 -0000	1.5
+++ libiberty/aclocal.m4	20 Feb 2003 20:41:52 -0000
@@ -87,6 +87,35 @@ then AC_DEFINE(NEED_DECLARATION_ERRNO, 1
 fi
 ])
 
+dnl See whether we need a declaration for a function.
+AC_DEFUN(libiberty_NEED_DECLARATION,
+[AC_MSG_CHECKING([whether $1 must be declared])
+AC_CACHE_VAL(libiberty_cv_decl_needed_$1,
+[AC_TRY_COMPILE([
+#include "confdefs.h"
+#include <stdio.h>
+#ifdef HAVE_STRING_H
+#include <string.h>
+#else
+#ifdef HAVE_STRINGS_H
+#include <strings.h>
+#endif
+#endif
+#ifdef HAVE_STDLIB_H
+#include <stdlib.h>
+#endif
+#ifdef HAVE_UNISTD_H
+#include <unistd.h>
+#endif],
+[char *(*pfn) = (char *(*)) $1],
+libiberty_cv_decl_needed_$1=no, libiberty_cv_decl_needed_$1=yes)])
+AC_MSG_RESULT($libiberty_cv_decl_needed_$1)
+if test $libiberty_cv_decl_needed_$1 = yes; then
+  AC_DEFINE([NEED_DECLARATION_]translit($1, [a-z], [A-Z]), 1,
+            [Define if $1 is not declared in system header files.])
+fi
+])dnl
+
 # FIXME: We temporarily define our own version of AC_PROG_CC.  This is
 # copied from autoconf 2.12, but does not call AC_PROG_CC_WORKS.  We
 # are probably using a cross compiler, which will not be able to fully
Index: libiberty/configure.in
===================================================================
RCS file: /big/fsf/rsync/gcc-cvs/gcc/libiberty/configure.in,v
retrieving revision 1.55
diff -u -p -r1.55 configure.in
--- libiberty/configure.in	30 Jan 2003 19:02:12 -0000	1.55
+++ libiberty/configure.in	20 Feb 2003 17:22:48 -0000
@@ -207,6 +207,7 @@ funcs="$funcs waitpid"
 vars="sys_errlist sys_nerr sys_siglist"
 
 checkfuncs="getrusage on_exit psignal strerror strsignal sysconf times sbrk gettimeofday"
+checkfuncs="$checkfuncs realpath canonicalize_file_name"
 
 # These are neither executed nor required, but they help keep
 # autoheader happy without adding a bunch of text to acconfig.h.
@@ -218,6 +219,7 @@ if test "x" = "y"; then
   AC_CHECK_FUNCS(strtod strtol strtoul tmpnam vasprintf vfprintf vprintf)
   AC_CHECK_FUNCS(vsprintf waitpid getrusage on_exit psignal strerror strsignal)
   AC_CHECK_FUNCS(sysconf times sbrk gettimeofday ffs)
+  AC_CHECK_FUNCS(realpath canonicalize_file_name)
   AC_DEFINE(HAVE_SYS_ERRLIST, 1, [Define if you have the sys_errlist variable.])
   AC_DEFINE(HAVE_SYS_NERR,    1, [Define if you have the sys_nerr variable.])
   AC_DEFINE(HAVE_SYS_SIGLIST, 1, [Define if you have the sys_siglist variable.])
@@ -424,6 +426,7 @@ if test -z "${setobjs}"; then
     fi
   done
   AC_CHECK_FUNCS($checkfuncs)
+  libiberty_NEED_DECLARATION(canonicalize_file_name)
 fi
 
 # Figure out which version of pexecute to use.
Index: libiberty/lrealpath.c
===================================================================
RCS file: libiberty/lrealpath.c
diff -N libiberty/lrealpath.c
--- /dev/null	1 Jan 1970 00:00:00 -0000
+++ libiberty/lrealpath.c	20 Feb 2003 20:44:03 -0000
@@ -0,0 +1,128 @@
+/* Libiberty realpath.  Like realpath, but more consistent behavior.
+   Based on gdb_realpath from GDB.
+
+   Copyright 2003 Free Software Foundation, Inc.
+
+   This file is part of the libiberty library.
+
+   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 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.  */
+
+/*
+
+@deftypefn Replacement {const char*} lrealpath (const char *@var{name})
+
+Given a pointer to a string containing a pathname, returns a canonical
+version of the filename.  Symlinks will be resolved, and ``.'' and ``..''
+components will be simplified.  The returned value will be allocated using
+@code{malloc}, or @code{NULL} will be returned on a memory allocation error.
+
+@end deftypefn
+
+*/
+
+#include "config.h"
+#include "ansidecl.h"
+#include "libiberty.h"
+
+#ifdef HAVE_LIMITS_H
+#include <limits.h>
+#endif
+#ifdef HAVE_STDLIB_H
+#include <stdlib.h>
+#endif
+#ifdef HAVE_UNISTD_H
+#include <unistd.h>
+#endif
+#ifdef HAVE_STRING_H
+#include <string.h>
+#endif
+
+/* On GNU libc systems the declaration is only visible with _GNU_SOURCE.  */
+#if defined(HAVE_CANONICALIZE_FILE_NAME) \
+    && defined(NEED_DECLARATION_CANONICALIZE_FILE_NAME)
+extern char *canonicalize_file_name (const char *);
+#endif
+
+#if defined(HAVE_REALPATH)
+# if defined (PATH_MAX)
+#  define REALPATH_LIMIT PATH_MAX
+# else
+#  if defined (MAXPATHLEN)
+#   define REALPATH_LIMIT MAXPATHLEN
+#  endif
+# endif
+#endif
+
+char *
+lrealpath (filename)
+     const char *filename;
+{
+  /* Method 1: The system has a compile time upper bound on a filename
+     path.  Use that and realpath() to canonicalize the name.  This is
+     the most common case.  Note that, if there isn't a compile time
+     upper bound, you want to avoid realpath() at all costs.  */
+#if defined(REALPATH_LIMIT)
+  {
+    char buf[REALPATH_LIMIT];
+    const char *rp = realpath (filename, buf);
+    if (rp == NULL)
+      rp = filename;
+    return strdup (rp);
+  }
+#endif /* REALPATH_LIMIT */
+
+  /* Method 2: The host system (i.e., GNU) has the function
+     canonicalize_file_name() which malloc's a chunk of memory and
+     returns that, use that.  */
+#if defined(HAVE_CANONICALIZE_FILE_NAME)
+  {
+    char *rp = canonicalize_file_name (filename);
+    if (rp == NULL)
+      return strdup (filename);
+    else
+      return rp;
+  }
+#endif
+
+  /* Method 3: Now we're getting desperate!  The system doesn't have a
+     compile time buffer size and no alternative function.  Query the
+     OS, using pathconf(), for the buffer limit.  Care is needed
+     though, some systems do not limit PATH_MAX (return -1 for
+     pathconf()) making it impossible to pass a correctly sized buffer
+     to realpath() (it could always overflow).  On those systems, we
+     skip this.  */
+#if defined (HAVE_REALPATH) && defined (HAVE_UNISTD_H)
+  {
+    /* Find out the max path size.  */
+    long path_max = pathconf ("/", _PC_PATH_MAX);
+    if (path_max > 0)
+      {
+	/* PATH_MAX is bounded.  */
+	char *buf, *rp, *ret;
+	buf = malloc (path_max);
+	if (buf == NULL)
+	  return NULL;
+	rp = realpath (filename, buf);
+	ret = strdup (rp ? rp : filename);
+	free (buf);
+	return ret;
+      }
+  }
+#endif
+
+  /* This system is a lost cause, just duplicate the filename.  */
+  return strdup (filename);
+}
Index: libiberty/make-relative-prefix.c
===================================================================
RCS file: /big/fsf/rsync/gcc-cvs/gcc/libiberty/make-relative-prefix.c,v
retrieving revision 1.3
diff -u -p -r1.3 make-relative-prefix.c
--- libiberty/make-relative-prefix.c	4 Dec 2002 01:57:27 -0000	1.3
+++ libiberty/make-relative-prefix.c	20 Feb 2003 20:45:22 -0000
@@ -23,16 +23,25 @@ Software Foundation, 59 Temple Place - S
 
 @deftypefn Extension {const char*} make_relative_prefix (const char *@var{progname}, const char *@var{bin_prefix}, const char *@var{prefix})
 
-Given three strings @var{progname}, @var{bin_prefix}, @var{prefix}, return a string
-that gets to @var{prefix} starting with the directory portion of @var{progname} and
-a relative pathname of the difference between @var{bin_prefix} and @var{prefix}.
-
-For example, if @var{bin_prefix} is @code{/alpha/beta/gamma/gcc/delta}, @var{prefix}
-is @code{/alpha/beta/gamma/omega/}, and @var{progname} is @code{/red/green/blue/gcc},
-then this function will return @code{/red/green/blue/../../omega/}.
+Given three paths @var{progname}, @var{bin_prefix}, @var{prefix},
+return the path that is in the same position relative to
+@var{progname}'s directory as @var{prefix} is relative to
+@var{bin_prefix}.  That is, a string starting with the directory
+portion of @var{progname}, followed by a relative pathname of the
+difference between @var{bin_prefix} and @var{prefix}.
+
+If @var{progname} does not contain any directory separators,
+@code{make_relative_prefix} will search @env{PATH} to find a program
+named @var{progname}.  Also, if @var{progname} is a symbolic link,
+the symbolic link will be resolved.
+
+For example, if @var{bin_prefix} is @code{/alpha/beta/gamma/gcc/delta},
+@var{prefix} is @code{/alpha/beta/gamma/omega/}, and @var{progname} is
+@code{/red/green/blue/gcc}, then this function will return
+@code{/red/green/blue/../../omega/}.
 
-The return value is normally allocated via @code{malloc}.  If no relative prefix
-can be found, return @code{NULL}.
+The return value is normally allocated via @code{malloc}.  If no
+relative prefix can be found, return @code{NULL}.
 
 @end deftypefn
 
@@ -223,19 +232,14 @@ make_relative_prefix (progname, bin_pref
   int prog_num, bin_num, prefix_num;
   int i, n, common;
   int needed_len;
-  char *ret, *ptr;
+  char *ret, *ptr, *full_progname = NULL;
 
   if (progname == NULL || bin_prefix == NULL || prefix == NULL)
     return NULL;
 
-  prog_dirs = split_directories (progname, &prog_num);
-  bin_dirs = split_directories (bin_prefix, &bin_num);
-  if (bin_dirs == NULL || prog_dirs == NULL)
-    return NULL;
-
   /* If there is no full pathname, try to find the program by checking in each
      of the directories specified in the PATH environment variable.  */
-  if (prog_num == 1)
+  if (lbasename (progname) == progname)
     {
       char *temp;
 
@@ -278,14 +282,7 @@ make_relative_prefix (progname, bin_pref
 #endif
 		      )
 		    {
-		      free_split_directories (prog_dirs);
 		      progname = nstore;
-		      prog_dirs = split_directories (progname, &prog_num);
-		      if (prog_dirs == NULL)
-			{
-			  free_split_directories (bin_dirs);
-			  return NULL;
-			}
 		      break;
 		    }
 
@@ -298,6 +295,16 @@ make_relative_prefix (progname, bin_pref
 	    }
 	}
     }
+
+  full_progname = lrealpath (progname);
+  if (full_progname == NULL)
+    return NULL;
+
+  prog_dirs = split_directories (full_progname, &prog_num);
+  bin_dirs = split_directories (bin_prefix, &bin_num);
+  free (full_progname);
+  if (bin_dirs == NULL || prog_dirs == NULL)
+    return NULL;
 
   /* Remove the program name from comparison of directory names.  */
   prog_num--;

Re: PATCH[libiberty] for Re: Mainline: C++ include files not found!

[DJ Delorie]

> 2003-02-20  Daniel Jacobowitz  <drow@mvista.com>
> 
> 	* libiberty.h (lrealpath): Add declaration.
> 
> 2003-02-20  Daniel Jacobowitz  <drow@mvista.com>
> 
> 	* Makefile.in (CFILES): Add lrealpath.c.
> 	(REQUIRED_OFILES): Add lrealpath.o.
> 	(lrealpath.o): Add rule.
> 	* aclocal.m4 (libiberty_NEED_DECLARATION): Add.
> 	* configure.in: Add realpath and canonicalize_file_name to
> 	checkfuncs and AC_CHECK_FUNCS.  Use libiberty_NEED_DECLARATION
> 	for canonicalize_file_name.
> 	* lrealpath.c: New file.
> 	* make-relative-prefix.c: Update documentation.
> 	(make_relative_prefix): Simplify.  Use lbasename and lrealpath.
> 	* config.in: Regenerated.
> 	* configure: Regenerated.
> 	* functions.texi: Regenerated.

Ok.