Re: [libvirt] 2 patches: dead increment and 4 useless (always-false) disjuncts

On Mon, Sep 07, 2009 at 05:37:24PM +0200, Jim Meyering wrote: > > >From 74f57af2010f9cbe2315d625c6502a0b259e6802 Mon Sep 17 00:00:00 2001 > From: Jim Meyering <meyering(a)redhat.com&gt; > Date: Mon, 7 Sep 2009 10:03:22 +0200 > Subject: [PATCH 1/2] xm_internal.c: remove dead increment of "data" > > * src/xm_internal.c (xenXMDomainConfigParse): Don't increment it. > --- > src/xm_internal.c | 1 - > 1 files changed, 0 insertions(+), 1 deletions(-) > > diff --git a/src/xm_internal.c b/src/xm_internal.c > index f206c8c..18613d4 100644 > --- a/src/xm_internal.c > +++ b/src/xm_internal.c > @@ -1314,7 +1314,6 @@ xenXMDomainConfigParse(virConnectPtr conn, virConfPtr conf) { > > if (!(data = strchr(key, '=')) || (data[0] == '\0')) > break; > - data++; > > if (graphics->type == VIR_DOMAIN_GRAPHICS_TYPE_VNC) { > if (STRPREFIX(key, "vncunused=")) { trivial, ACK > >From d4db2dfaafbf827d1c8b8626a3dbdaa9f371e479 Mon Sep 17 00:00:00 2001 > From: Jim Meyering <meyering(a)redhat.com&gt; > Date: Mon, 7 Sep 2009 10:09:20 +0200 > Subject: [PATCH 2/2] xm_internal.c: remove four useless comparisons after strchr > > * src/xm_internal.c (xenXMDomainConfigParse): After t=strchr... > don't test *t; it's known. This was *not* detected by clang, > but I spotted it since once instance was in the vicinity of the > dead increment of "data". > --- > src/xm_internal.c | 8 ++++---- > 1 files changed, 4 insertions(+), 4 deletions(-) > > diff --git a/src/xm_internal.c b/src/xm_internal.c > index 18613d4..e7f6a55 100644 > --- a/src/xm_internal.c > +++ b/src/xm_internal.c > @@ -862,7 +862,7 @@ xenXMDomainConfigParse(virConnectPtr conn, virConfPtr conf) { > */ > > /* Extract the source file path*/ > - if (!(offset = strchr(head, ',')) || offset[0] == '\0') > + if (!(offset = strchr(head, ','))) > goto skipdisk; > if ((offset - head) >= (PATH_MAX-1)) > goto skipdisk; > @@ -882,7 +882,7 @@ xenXMDomainConfigParse(virConnectPtr conn, virConfPtr conf) { > head = head + 6; > > /* Extract the dest device name */ > - if (!(offset = strchr(head, ',')) || offset[0] == '\0') > + if (!(offset = strchr(head, ','))) > goto skipdisk; > if (VIR_ALLOC_N(disk->dst, (offset - head) + 1) < 0) > goto no_memory; > @@ -1018,7 +1018,7 @@ xenXMDomainConfigParse(virConnectPtr conn, virConfPtr conf) { > char *data; > char *nextkey = strchr(key, ','); > > - if (!(data = strchr(key, '=')) || (data[0] == '\0')) > + if (!(data = strchr(key, '='))) > goto skipnic; > data++; > > @@ -1312,7 +1312,7 @@ xenXMDomainConfigParse(virConnectPtr conn, virConfPtr conf) { > nextkey++; > } > > - if (!(data = strchr(key, '=')) || (data[0] == '\0')) > + if (!(data = strchr(key, '='))) > break; > > if (graphics->type == VIR_DOMAIN_GRAPHICS_TYPE_VNC) { Hum, I would like to understand the intent of the person who wrote this first, it's like one s trying to handle a case where strchr( ,c) could return the pointer to the end of string if c is not found or something like that. Weird ...