Re: [libvirt] [PATCH 1/2] virCommand: document behavior on no output
On Sun, Dec 05, 2010 at 12:55:51AM +0100, Matthias Bolte wrote: > 2010/12/4 Justin Clift : > > On 04/12/2010, at 8:28 AM, Eric Blake wrote: > >> Option 1: This patch (all callers have to worry about NULL buffers, > >> but checking for output is a simple pointer check). > >> > >> Option 2: Guarantee that outbuf/errbuf are allocated, even if to > >> the empty string. Caller always has to free the result, and > >> empty output check requires checking if *outbuf=='\0'. > >> > >> Personally, I prefer option 2. Thoughts? > > > > 2 seems safer. > > > > I vote for the second version too. me too :-) ACK on 2/2 Daniel -- Daniel Veillard | libxml Gnome XML XSLT toolkit http://xmlsoft.org/ dan...@veillard.com | Rpmfind RPM search engine http://rpmfind.net/ http://veillard.com/ | virtualization library http://libvirt.org/ -- libvir-list mailing list libvir-list@redhat.com https://www.redhat.com/mailman/listinfo/libvir-list
Re: [libvirt] [PATCH 1/2] virCommand: document behavior on no output
2010/12/4 Justin Clift : > On 04/12/2010, at 8:28 AM, Eric Blake wrote: >> Option 1: This patch (all callers have to worry about NULL buffers, >> but checking for output is a simple pointer check). >> >> Option 2: Guarantee that outbuf/errbuf are allocated, even if to >> the empty string. Caller always has to free the result, and >> empty output check requires checking if *outbuf=='\0'. >> >> Personally, I prefer option 2. Thoughts? > > 2 seems safer. > I vote for the second version too. Matthias -- libvir-list mailing list libvir-list@redhat.com https://www.redhat.com/mailman/listinfo/libvir-list
Re: [libvirt] [PATCH 1/2] virCommand: document behavior on no output
On 04/12/2010, at 8:28 AM, Eric Blake wrote: > Option 1: This patch (all callers have to worry about NULL buffers, > but checking for output is a simple pointer check). > > Option 2: Guarantee that outbuf/errbuf are allocated, even if to > the empty string. Caller always has to free the result, and > empty output check requires checking if *outbuf=='\0'. > > Personally, I prefer option 2. Thoughts? 2 seems safer. -- libvir-list mailing list libvir-list@redhat.com https://www.redhat.com/mailman/listinfo/libvir-list
[libvirt] [PATCH 1/2] virCommand: document behavior on no output
Option 1: This patch (all callers have to worry about NULL buffers, but checking for output is a simple pointer check). Option 2: Guarantee that outbuf/errbuf are allocated, even if to the empty string. Caller always has to free the result, and empty output check requires checking if *outbuf=='\0'. Personally, I prefer option 2. Thoughts? * docs/internals/command.html.in: Update documentation. * src/util/command.c (virCommandSetOutputBuffer) (virCommandSetErrorBuffer) Guarantee NULL buffer on no output. --- docs/internals/command.html.in |4 ++-- src/util/command.c |2 ++ 2 files changed, 4 insertions(+), 2 deletions(-) diff --git a/docs/internals/command.html.in b/docs/internals/command.html.in index c4fa800..ea9ec64 100644 --- a/docs/internals/command.html.in +++ b/docs/internals/command.html.in @@ -349,8 +349,8 @@ Once the command has finished executing, these buffers - will contain the output. It is the callers responsibility - to free these buffers. + will contain the output, or be NULL if there was no output. It + is the callers responsibility to free these buffers. Setting working directory diff --git a/src/util/command.c b/src/util/command.c index aa43f76..1923799 100644 --- a/src/util/command.c +++ b/src/util/command.c @@ -549,6 +549,7 @@ virCommandSetOutputBuffer(virCommandPtr cmd, char **outbuf) return; } +VIR_FREE(*outbuf); cmd->outbuf = outbuf; cmd->outfdptr = &cmd->outfd; } @@ -569,6 +570,7 @@ virCommandSetErrorBuffer(virCommandPtr cmd, char **errbuf) return; } +VIR_FREE(*errbuf); cmd->errbuf = errbuf; cmd->errfdptr = &cmd->errfd; } -- 1.7.3.2 -- libvir-list mailing list libvir-list@redhat.com https://www.redhat.com/mailman/listinfo/libvir-list
