[2787] in BarnOwl Developers
Re: [PATCH 1/2] Fixed :unsub to make it work if ~/.zephyr.subs is a symlink (trac 133)
daemon@ATHENA.MIT.EDU (Karl Ramm)
Mon Nov 15 17:01:27 2010
From: Karl Ramm <kcr@1ts.org>
To: David A Benjamin <davidben@mit.edu>
Cc: barnowl-dev@mit.edu
Date: Mon, 15 Nov 2010 17:01:24 -0500
In-Reply-To: <alpine.DEB.1.10.1011151646570.15631@dr-wily.mit.edu> (David
A. Benjamin's message of "Mon, 15 Nov 2010 16:48:43 -0500 (EST)")
David A Benjamin <davidben@MIT.EDU> writes:
> The man pages says it's equivalent to realpath(path, NULL)
> which... doesn't appear to be a GNUism?
>
> We can also add another AC_REPLACE_FUNCS, but they're annoying.
>
> David
It's in POSIX 2001 so we.. probably get to point and laugh if someone
doesn't have it?
kcr
> On Mon, 15 Nov 2010, Karl Ramm wrote:
>
>> I said looks good to me, before, but I notice that canonicalize_file_name
>> is a GNUism; do we want to give up and only work on glibc systems?
>>
>> kcr
>>
>> (Oh hey, that can has worms crawling out)
>>
>> Jason Gross <jgross@MIT.EDU> writes:
>>
>>> From: Jason <jgross@mit.edu>
>>>
>>> link() fails on AFS if the target is a symlink. Additionally, on
>>> systems where link() succeeds, barnowl overwrites the symlink, instead
>>> of the actual file. To fix this, I've changed owl_util_file_deleteline
>>> to call canonicalize_file_name on the passed file name first. The new
>>> (backup) file is written in the resolved directory, not the directory
>>> where the symlink itself is found.
>>>
>>> Additionally, I corrected free(filename) to owl_free(filename) in the
>>> two places that it occurred.
>>> ---
>>> util.c | 34 ++++++++++++++++++++++++----------
>>> 1 files changed, 24 insertions(+), 10 deletions(-)
>>>
>>> diff --git a/util.c b/util.c
>>> index 6546c73..cdbfd01 100644
>>> --- a/util.c
>>> +++ b/util.c
>>> @@ -384,38 +384,50 @@ char *owl_util_stripnewlines(const char *in)
>>> */
>>> int owl_util_file_deleteline(const char *filename, const char *line, int backup)
>>> {
>>> - char *backupfile, *newfile, *buf = NULL;
>>> + char *actual_filename, *backupfile, *newfile, *buf = NULL;
>>> FILE *old, *new;
>>> struct stat st;
>>> int numremoved = 0;
>>>
>>> + /* canonicalize filename, so that we deal with with symlinks correctly */
>>> + actual_filename = canonicalize_file_name(filename);
>>> + if (actual_filename == NULL) {
>>> + owl_function_error("Cannot canonicalize file name %s: %s",
>>> + actual_filename, strerror(errno));
>>> + return 0;
>>> + }
>>> +
>>> if ((old = fopen(filename, "r")) == NULL) {
>>> owl_function_error("Cannot open %s (for reading): %s",
>>> filename, strerror(errno));
>>> + free(actual_filename);
>>> return 0;
>>> }
>>>
>>> if (fstat(fileno(old), &st) != 0) {
>>> owl_function_error("Cannot stat %s: %s", filename, strerror(errno));
>>> + free(actual_filename);
>>> return 0;
>>> }
>>>
>>> - newfile = owl_sprintf("%s.new", filename);
>>> + newfile = owl_sprintf("%s.new", actual_filename);
>>> if ((new = fopen(newfile, "w")) == NULL) {
>>> owl_function_error("Cannot open %s (for writing): %s",
>>> - filename, strerror(errno));
>>> - free(newfile);
>>> + actual_filename, strerror(errno));
>>> + owl_free(newfile);
>>> fclose(old);
>>> + free(actual_filename);
>>> return 0;
>>> }
>>>
>>> if (fchmod(fileno(new), st.st_mode & 0777) != 0) {
>>> owl_function_error("Cannot set permissions on %s: %s",
>>> - filename, strerror(errno));
>>> + actual_filename, strerror(errno));
>>> unlink(newfile);
>>> fclose(new);
>>> - free(newfile);
>>> + owl_free(newfile);
>>> fclose(old);
>>> + free(actual_filename);
>>> return 0;
>>> }
>>>
>>> @@ -430,9 +442,9 @@ int owl_util_file_deleteline(const char *filename, const char *line, int backup)
>>> fclose(old);
>>>
>>> if (backup) {
>>> - backupfile = owl_sprintf("%s.backup", filename);
>>> + backupfile = owl_sprintf("%s.backup", actual_filename);
>>> unlink(backupfile);
>>> - if (link(filename, backupfile) != 0) {
>>> + if (link(actual_filename, backupfile) != 0) {
>>> owl_function_error("Cannot link %s: %s", backupfile, strerror(errno));
>>> owl_free(backupfile);
>>> unlink(newfile);
>>> @@ -442,15 +454,17 @@ int owl_util_file_deleteline(const char *filename, const char *line, int backup)
>>> owl_free(backupfile);
>>> }
>>>
>>> - if (rename(newfile, filename) != 0) {
>>> + if (rename(newfile, actual_filename) != 0) {
>>> owl_function_error("Cannot move %s to %s: %s",
>>> - newfile, filename, strerror(errno));
>>> + newfile, actual_filename, strerror(errno));
>>> numremoved = 0;
>>> }
>>>
>>> unlink(newfile);
>>> owl_free(newfile);
>>>
>>> + free(actual_filename);
>>> +
>>> return numremoved;
>>> }
>>
