# [PATCH] Don't rely on unspecified behavior 11 messages from 2007-07-28 to 2007-07-28. Participants: Thomas Schwinge, Thomas Glanzmann, Johannes Schindelin. Thread: https://gitlist.dev/t/9277 ## Thomas Schwinge, 2007-07-28 16:39 Subject: [PATCH] Support building on GNU/Hurd Message-ID: <11856407793933-git-send-email-tschwinge@gnu.org> URL: https://gitlist.dev/e/11856407793933-git-send-email-tschwinge%40gnu.org ``` GNU/Hurd systems don't have strlcpy either. Signed-off-by: Thomas Schwinge --- Makefile | 4 ++++ 1 files changed, 4 insertions(+), 0 deletions(-) diff --git a/Makefile b/Makefile index 2fea115..8d9a01b 100644 --- a/Makefile +++ b/Makefile @@ -458,6 +458,10 @@ ifeq ($(uname_S),AIX) NO_STRLCPY = YesPlease NEEDS_LIBICONV=YesPlease endif +ifeq ($(uname_S),GNU) + # GNU/Hurd + NO_STRLCPY=YesPlease +endif ifeq ($(uname_S),IRIX64) NO_IPV6=YesPlease NO_SETENV=YesPlease -- 1.5.3.rc3.26.g6c58-dirty ``` ## Thomas Schwinge, 2007-07-28 16:39 Subject: [PATCH] Don't rely on unspecified behavior Message-ID: <11856407791617-git-send-email-tschwinge@gnu.org> URL: https://gitlist.dev/e/11856407791617-git-send-email-tschwinge%40gnu.org In-Reply-To: <11856407793933-git-send-email-tschwinge@gnu.org> ``` Calling access(p, m) with p == NULL is not specified, so don't do that. On GNU/Hurd systems doing so will result in an SIGSEGV. Signed-off-by: Thomas Schwinge --- builtin-add.c | 2 +- 1 files changed, 1 insertions(+), 1 deletions(-) diff --git a/builtin-add.c b/builtin-add.c index 5e6748f..c13c738 100644 --- a/builtin-add.c +++ b/builtin-add.c @@ -74,7 +74,7 @@ static void fill_directory(struct dir_struct *dir, const char **pathspec) path = git_path("info/exclude"); if (!access(path, R_OK)) add_excludes_from_file(dir, path); - if (!access(excludes_file, R_OK)) + if (excludes_file != NULL && !access(excludes_file, R_OK)) add_excludes_from_file(dir, excludes_file); /* -- 1.5.3.rc3.26.g6c58-dirty ``` ## Thomas Glanzmann, 2007-07-28 17:39 Subject: Re: [PATCH] Don't rely on unspecified behavior Message-ID: <20070728173948.GD23337@cip.informatik.uni-erlangen.de> URL: https://gitlist.dev/e/20070728173948.GD23337%40cip.informatik.uni-erlangen.de In-Reply-To: <11856407791617-git-send-email-tschwinge@gnu.org> ``` Hello, > Calling access(p, m) with p == NULL is not specified, so don't do > that. On GNU/Hurd systems doing so will result in an SIGSEGV. a friend of mine choked on this one when tried git for the second time (the first time "git-repack -a -d -f" screwed his repository after the initial checkout. This is fixed for a long time). Lucky me that he had his libusbdriver in LD_PRELOAD which could not handle the NULL argument. And I always thought libc would make the check before it does the system call or does GNU/hurts not use the gnu libc? Thomas ``` ## Thomas Schwinge, 2007-07-28 18:25 Subject: Re: [PATCH] Don't rely on unspecified behavior Message-ID: <20070728182542.GA22651@fencepost.gnu.org> URL: https://gitlist.dev/e/20070728182542.GA22651%40fencepost.gnu.org In-Reply-To: <20070728173948.GD23337@cip.informatik.uni-erlangen.de> ``` Hello! On Sat, Jul 28, 2007 at 07:39:48PM +0200, Thomas Glanzmann wrote: > > Calling access(p, m) with p == NULL is not specified, so don't do > > that. On GNU/Hurd systems doing so will result in an SIGSEGV. > > a friend of mine choked on this one when tried git for the second time > (the first time "git-repack -a -d -f" screwed his repository after the > initial checkout. This is fixed for a long time). Lucky me that he had > his libusbdriver in LD_PRELOAD which could not handle the NULL argument. > And I always thought libc would make the check before it does the system > call or does GNU/hurts not use the gnu libc? GNU/Hurd systems do (obviously ;-) use the GNU libc. The glibc maintainer Roland McGrath explicitly told me that ``access (NULL, m)'' shall not be caught as it is not specified and thus must not be invoked like this. I noticed that the patch I sent was prepared for an old version of the file. I'll send an updated patch that applies to the current revision. Regards, Thomas ``` ## Thomas Schwinge, 2007-07-28 18:26 Subject: [PATCH] Don't rely on unspecified behavior Message-ID: <11856471952272-git-send-email-tschwinge@gnu.org> URL: https://gitlist.dev/e/11856471952272-git-send-email-tschwinge%40gnu.org In-Reply-To: <20070728173948.GD23337@cip.informatik.uni-erlangen.de> ``` Calling access(p, m) with p == NULL is not specified, so don't do that. On GNU/Hurd systems doing so will result in a SIGSEGV. Signed-off-by: Thomas Schwinge --- builtin-add.c | 2 +- 1 files changed, 1 insertions(+), 1 deletions(-) diff --git a/builtin-add.c b/builtin-add.c index 7345479..de5c108 100644 --- a/builtin-add.c +++ b/builtin-add.c @@ -60,7 +60,7 @@ static void fill_directory(struct dir_struct *dir, const char **pathspec, path = git_path("info/exclude"); if (!access(path, R_OK)) add_excludes_from_file(dir, path); - if (!access(excludes_file, R_OK)) + if (excludes_file != NULL && !access(excludes_file, R_OK)) add_excludes_from_file(dir, excludes_file); } -- 1.5.3.rc3.26.g6c58-dirty ``` ## Johannes Schindelin, 2007-07-28 19:30 Subject: Re: [PATCH] Don't rely on unspecified behavior Message-ID: URL: https://gitlist.dev/e/Pine.LNX.4.64.0707282028130.14781%40racer.site In-Reply-To: <11856471952272-git-send-email-tschwinge@gnu.org> ``` Hi, On Sat, 28 Jul 2007, Thomas Schwinge wrote: > Calling access(p, m) with p == NULL is not specified, so don't do that. On > GNU/Hurd systems doing so will result in a SIGSEGV. > > Signed-off-by: Thomas Schwinge > --- Isn't this the same patch as you sent before? > builtin-add.c | 2 +- > 1 files changed, 1 insertions(+), 1 deletions(-) > > diff --git a/builtin-add.c b/builtin-add.c > index 7345479..de5c108 100644 > --- a/builtin-add.c > +++ b/builtin-add.c > @@ -60,7 +60,7 @@ static void fill_directory(struct dir_struct *dir, const char **pathspec, > path = git_path("info/exclude"); > if (!access(path, R_OK)) > add_excludes_from_file(dir, path); > - if (!access(excludes_file, R_OK)) > + if (excludes_file != NULL && !access(excludes_file, R_OK)) We usually omit the "!= NULL"; see the other source code in git.git. Ciao, Dscho ``` ## Thomas Glanzmann, 2007-07-28 19:34 Subject: Re: [PATCH] Don't rely on unspecified behavior Message-ID: <20070728193402.GE23337@cip.informatik.uni-erlangen.de> URL: https://gitlist.dev/e/20070728193402.GE23337%40cip.informatik.uni-erlangen.de In-Reply-To: ``` Hello Dscho, > Isn't this the same patch as you sent before? > > @@ -74,7 +74,7 @@ static void fill_directory(struct dir_struct *dir, const char **pathspec) > > @@ -60,7 +60,7 @@ static void fill_directory(struct dir_struct *dir, const char **pathspec, ~~~~~ ~~~~~ ~ The offset of the diff has changed. Not that git couldn't sort it out by itself. And the function had one or more parameters less. Thomas ``` ## Thomas Schwinge, 2007-07-28 19:43 Subject: Re: [PATCH] Don't rely on unspecified behavior Message-ID: <20070728194306.GA32203@fencepost.gnu.org> URL: https://gitlist.dev/e/20070728194306.GA32203%40fencepost.gnu.org In-Reply-To: ``` Hello! On Sat, Jul 28, 2007 at 08:30:07PM +0100, Johannes Schindelin wrote: > On Sat, 28 Jul 2007, Thomas Schwinge wrote: > > Calling access(p, m) with p == NULL is not specified, so don't do that. On > > GNU/Hurd systems doing so will result in a SIGSEGV. > > > > Signed-off-by: Thomas Schwinge > > --- > > Isn't this the same patch as you sent before? As I wrote in <20070728182542.GA22651@fencepost.gnu.org>: ``I noticed that the patch I sent was prepared for an old version of the file. I'll send an updated patch that applies to the current revision.'' > > + if (excludes_file != NULL && !access(excludes_file, R_OK)) > > We usually omit the "!= NULL"; see the other source code in git.git. Okay, so I should sent a thusly modified version to get it applied? Regards, Thomas ``` ## Johannes Schindelin, 2007-07-28 20:16 Subject: Re: [PATCH] Don't rely on unspecified behavior Message-ID: URL: https://gitlist.dev/e/Pine.LNX.4.64.0707282115450.14781%40racer.site In-Reply-To: <20070728193402.GE23337@cip.informatik.uni-erlangen.de> ``` Hi, On Sat, 28 Jul 2007, Thomas Glanzmann wrote: > > Isn't this the same patch as you sent before? > > > > @@ -74,7 +74,7 @@ static void fill_directory(struct dir_struct *dir, const char **pathspec) > > > @@ -60,7 +60,7 @@ static void fill_directory(struct dir_struct *dir, const char **pathspec, > ~~~~~ ~~~~~ ~ > > The offset of the diff has changed. Not that git couldn't sort it out by > itself. And the function had one or more parameters less. Ah. Thanks for the explanation. Ciao, Dscho ``` ## Johannes Schindelin, 2007-07-28 20:17 Subject: Re: [PATCH] Don't rely on unspecified behavior Message-ID: URL: https://gitlist.dev/e/Pine.LNX.4.64.0707282116390.14781%40racer.site In-Reply-To: <20070728194306.GA32203@fencepost.gnu.org> ``` Hi, On Sat, 28 Jul 2007, Thomas Schwinge wrote: > On Sat, Jul 28, 2007 at 08:30:07PM +0100, Johannes Schindelin wrote: > > On Sat, 28 Jul 2007, Thomas Schwinge wrote: > > > Calling access(p, m) with p == NULL is not specified, so don't do that. On > > > GNU/Hurd systems doing so will result in a SIGSEGV. > > > > > > Signed-off-by: Thomas Schwinge > > > --- > > > > Isn't this the same patch as you sent before? > > As I wrote in <20070728182542.GA22651@fencepost.gnu.org>: ``I noticed > that the patch I sent was prepared for an old version of the file. I'll > send an updated patch that applies to the current revision.'' Ah. > > > + if (excludes_file != NULL && !access(excludes_file, R_OK)) > > > > We usually omit the "!= NULL"; see the other source code in git.git. > > Okay, so I should sent a thusly modified version to get it applied? I don't think that is necessary; a small change like this is usually fixed by Junio with --amend. Ciao, Dscho ``` ## Thomas Glanzmann, 2007-07-28 20:20 Subject: Re: [PATCH] Don't rely on unspecified behavior Message-ID: <20070728202054.GA3616@cip.informatik.uni-erlangen.de> URL: https://gitlist.dev/e/20070728202054.GA3616%40cip.informatik.uni-erlangen.de In-Reply-To: ``` Hello, > Ah. Thanks for the explanation. I have operating system / real time systems exam on monday. I have to prepare myself in stating the obvious. Thomas ```