# --- SDE-COPYRIGHT-NOTE-BEGIN --- # This copyright note is auto-generated by ./scripts/Create-CopyPatch. # # Filename: package/.../make/make-3.82-0007-copy-on-expand.patch # Copyright (C) 2012 The OpenSDE Project # # More information can be found in the files COPYING and README. # # This patch file is dual-licensed. It is available under the license the # patched project is licensed under, as long as it is an OpenSource license # as defined at http://www.opensource.org/ (e.g. BSD, X11) or 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. # --- SDE-COPYRIGHT-NOTE-END --- From 3d11dcdc977ef7db3897663b806fe08856ca4190 Mon Sep 17 00:00:00 2001 From: Christian Wiese <chris@opensde.org> Date: Mon, 22 Oct 2012 18:05:12 +0200 Subject: [PATCH] copy on expand ChangeLog: 2011-08-29 Paul Smith <psmith@gnu.org> * expand.c (variable_expand_string): Always allocate a new buffer for a string we're expanding. The string we're working on can get freed while we work on it (for example if it's the value of a variable which modifies itself using an eval operation). See Savannah patch #7534 for the original report by Lubomir Rintel. tests/ChangeLog: 2011-08-29 Paul Smith <psmith@gnu.org> * scripts/features/varnesting: Test resetting of variables while expanding them. See Savannah patch #7534 --- expand.c | 20 +++++---------- tests/scripts/features/varnesting | 47 +++++++++++++++++++------------------ 2 files changed, 31 insertions(+), 36 deletions(-) diff --git a/expand.c b/expand.c index 2315b06..9aeaa13 100644 --- a/expand.c +++ b/expand.c @@ -197,7 +197,7 @@ variable_expand_string (char *line, const char *string, long length) { struct variable *v; const char *p, *p1; - char *abuf = NULL; + char *save; char *o; unsigned int line_offset; @@ -212,16 +212,11 @@ variable_expand_string (char *line, const char *string, long length) return (variable_buffer); } - /* If we want a subset of the string, allocate a temporary buffer for it. - Most of the functions we use here don't work with length limits. */ - if (length > 0 && string[length] != '\0') - { - abuf = xmalloc(length+1); - memcpy(abuf, string, length); - abuf[length] = '\0'; - string = abuf; - } - p = string; + /* We need a copy of STRING: due to eval, it's possible that it will get + freed as we process it (it might be the value of a variable that's reset + for example). Also having a nil-terminated string is handy. */ + save = length < 0 ? xstrdup (string) : xstrndup (string, length); + p = save; while (1) { @@ -411,8 +406,7 @@ variable_expand_string (char *line, const char *string, long length) ++p; } - if (abuf) - free (abuf); + free (save); variable_buffer_output (o, "", 1); return (variable_buffer + line_offset); diff --git a/tests/scripts/features/varnesting b/tests/scripts/features/varnesting index 15d5071..d8f3ffb 100644 --- a/tests/scripts/features/varnesting +++ b/tests/scripts/features/varnesting @@ -1,29 +1,30 @@ -$description = "The following test creates a makefile to ..."; +# -*-perl-*- +$description = "Test recursive variables"; $details = ""; -open(MAKEFILE,"> $makefile"); - -# The Contents of the MAKEFILE ... - -print MAKEFILE "x = variable1\n" - ."variable2 := Hello\n" - ."y = \$(subst 1,2,\$(x))\n" - ."z = y\n" - ."a := \$(\$(\$(z)))\n" - ."all: \n" - ."\t\@echo \$(a)\n"; - -# END of Contents of MAKEFILE - -close(MAKEFILE); - -&run_make_with_options($makefile,"",&get_logfile); - -# Create the answer to what should be produced by this Makefile -$answer = "Hello\n"; - -&compare_output($answer,&get_logfile(1)); +run_make_test(' +x = variable1 +variable2 := Hello +y = $(subst 1,2,$(x)) +z = y +a := $($($(z))) +all: + @echo $(a) +', + '', "Hello\n"); + +# This tests resetting the value of a variable while expanding it. +# You may only see problems with this if you're using valgrind or +# some other memory checker that poisons freed memory. +# See Savannah patch #7534 + +run_make_test(' +VARIABLE = $(eval VARIABLE := echo hi)$(VARIABLE) +wololo: + @$(VARIABLE) +', + '', "hi\n"); 1; -- 1.7.2.3