mirror of
https://sourceware.org/git/glibc.git
synced 2024-09-19 16:10:01 +00:00
argp: Avoid undefined behaviour when invoking qsort().
This fixes a Gnulib test-argp-2.sh test failure on macOS and FreeBSD. Reported by Jeffrey Walton <noloader@gmail.com> in <https://lists.gnu.org/archive/html/bug-gnulib/2020-03/msg00085.html>. * argp/argp-help.c (group_cmp): Remove third argument. (hol_sibling_cluster_cmp, hol_cousin_cluster_cmp): New functions, based upon hol_cluster_cmp. (hol_cluster_cmp): Use hol_cousin_cluster_cmp. (hol_entry_cmp): Rewritten to implement a total order. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
This commit is contained in:
Bruno Haible
Adhemerval Zanella
parent
bbf15241db
commit
1e3d9c1e4d
242
argp/argp-help.c
242
argp/argp-help.c
@ -668,37 +668,90 @@ hol_set_group (struct hol *hol, const char *name, int group)
|
||||
/* -------------------------------------------------------------------------- */
|
||||
/* Sorting the entries in a HOL. */
|
||||
|
||||
/* Order by group: 0, 1, 2, ..., n, -m, ..., -2, -1.
|
||||
EQ is what to return if GROUP1 and GROUP2 are the same. */
|
||||
/* Order by group: 0, 1, 2, ..., n, -m, ..., -2, -1. */
|
||||
static int
|
||||
group_cmp (int group1, int group2, int eq)
|
||||
group_cmp (int group1, int group2)
|
||||
{
|
||||
if (group1 == group2)
|
||||
return eq;
|
||||
else if ((group1 < 0 && group2 < 0) || (group1 >= 0 && group2 >= 0))
|
||||
if ((group1 < 0 && group2 < 0) || (group1 >= 0 && group2 >= 0))
|
||||
return group1 - group2;
|
||||
else
|
||||
/* Return > 0 if group1 < 0 <= group2.
|
||||
Return < 0 if group2 < 0 <= group1. */
|
||||
return group2 - group1;
|
||||
}
|
||||
|
||||
/* Compare clusters CL1 & CL2 by the order that they should appear in
|
||||
/* Compare clusters CL1 and CL2 by the order that they should appear in
|
||||
output. Assume CL1 and CL2 have the same parent. */
|
||||
static int
|
||||
hol_sibling_cluster_cmp (const struct hol_cluster *cl1,
|
||||
const struct hol_cluster *cl2)
|
||||
{
|
||||
/* Compare by group first. */
|
||||
int cmp = group_cmp (cl1->group, cl2->group);
|
||||
if (cmp != 0)
|
||||
return cmp;
|
||||
|
||||
/* Within a group, compare by index within the group. */
|
||||
return cl2->index - cl1->index;
|
||||
}
|
||||
|
||||
/* Compare clusters CL1 and CL2 by the order that they should appear in
|
||||
output. Assume CL1 and CL2 are at the same depth. */
|
||||
static int
|
||||
hol_cousin_cluster_cmp (const struct hol_cluster *cl1,
|
||||
const struct hol_cluster *cl2)
|
||||
{
|
||||
if (cl1->parent == cl2->parent)
|
||||
return hol_sibling_cluster_cmp (cl1, cl2);
|
||||
else
|
||||
{
|
||||
/* Compare the parent clusters first. */
|
||||
int cmp = hol_cousin_cluster_cmp (cl1->parent, cl2->parent);
|
||||
if (cmp != 0)
|
||||
return cmp;
|
||||
|
||||
/* Next, compare by group. */
|
||||
cmp = group_cmp (cl1->group, cl2->group);
|
||||
if (cmp != 0)
|
||||
return cmp;
|
||||
|
||||
/* Next, within a group, compare by index within the group. */
|
||||
return cl2->index - cl1->index;
|
||||
}
|
||||
}
|
||||
|
||||
/* Compare clusters CL1 and CL2 by the order that they should appear in
|
||||
output. */
|
||||
static int
|
||||
hol_cluster_cmp (const struct hol_cluster *cl1, const struct hol_cluster *cl2)
|
||||
{
|
||||
/* If one cluster is deeper than the other, use its ancestor at the same
|
||||
level, so that finding the common ancestor is straightforward. */
|
||||
while (cl1->depth > cl2->depth)
|
||||
level. Then, go by the rule that entries that are not in a sub-cluster
|
||||
come before entries in a sub-cluster. */
|
||||
if (cl1->depth > cl2->depth)
|
||||
{
|
||||
do
|
||||
cl1 = cl1->parent;
|
||||
while (cl2->depth > cl1->depth)
|
||||
while (cl1->depth > cl2->depth);
|
||||
int cmp = hol_cousin_cluster_cmp (cl1, cl2);
|
||||
if (cmp != 0)
|
||||
return cmp;
|
||||
|
||||
return 1;
|
||||
}
|
||||
else if (cl1->depth < cl2->depth)
|
||||
{
|
||||
do
|
||||
cl2 = cl2->parent;
|
||||
while (cl1->depth < cl2->depth);
|
||||
int cmp = hol_cousin_cluster_cmp (cl1, cl2);
|
||||
if (cmp != 0)
|
||||
return cmp;
|
||||
|
||||
/* Now reduce both clusters to their ancestors at the point where both have
|
||||
a common parent; these can be directly compared. */
|
||||
while (cl1->parent != cl2->parent)
|
||||
cl1 = cl1->parent, cl2 = cl2->parent;
|
||||
|
||||
return group_cmp (cl1->group, cl2->group, cl2->index - cl1->index);
|
||||
return -1;
|
||||
}
|
||||
else
|
||||
return hol_cousin_cluster_cmp (cl1, cl2);
|
||||
}
|
||||
|
||||
/* Return the ancestor of CL that's just below the root (i.e., has a parent
|
||||
@ -710,7 +763,7 @@ hol_cluster_base (struct hol_cluster *cl)
|
||||
cl = cl->parent;
|
||||
return cl;
|
||||
}
|
||||
|
||||
|
||||
/* Given the name of an OPTION_DOC option, modifies *NAME to start at the tail
|
||||
that should be used for comparisons, and returns true iff it should be
|
||||
treated as a non-option. */
|
||||
@ -721,7 +774,7 @@ canon_doc_option (const char **name)
|
||||
/* Skip initial whitespace. */
|
||||
while (isspace ((unsigned char) **name))
|
||||
(*name)++;
|
||||
/* Decide whether this looks like an option (leading `-') or not. */
|
||||
/* Decide whether this looks like an option (leading '-') or not. */
|
||||
non_opt = (**name != '-');
|
||||
/* Skip until part of name used for sorting. */
|
||||
while (**name && !isalnum ((unsigned char) **name))
|
||||
@ -729,77 +782,116 @@ canon_doc_option (const char **name)
|
||||
return non_opt;
|
||||
}
|
||||
|
||||
/* Order ENTRY1 & ENTRY2 by the order which they should appear in a help
|
||||
listing. */
|
||||
/* Order ENTRY1 and ENTRY2 by the order which they should appear in a help
|
||||
listing.
|
||||
This function implements a total order, that is:
|
||||
- if cmp (entry1, entry2) < 0 and cmp (entry2, entry3) < 0,
|
||||
then cmp (entry1, entry3) < 0.
|
||||
- if cmp (entry1, entry2) < 0 and cmp (entry2, entry3) == 0,
|
||||
then cmp (entry1, entry3) < 0.
|
||||
- if cmp (entry1, entry2) == 0 and cmp (entry2, entry3) < 0,
|
||||
then cmp (entry1, entry3) < 0.
|
||||
- if cmp (entry1, entry2) == 0 and cmp (entry2, entry3) == 0,
|
||||
then cmp (entry1, entry3) == 0. */
|
||||
static int
|
||||
hol_entry_cmp (const struct hol_entry *entry1,
|
||||
const struct hol_entry *entry2)
|
||||
{
|
||||
/* The group numbers by which the entries should be ordered; if either is
|
||||
in a cluster, then this is just the group within the cluster. */
|
||||
int group1 = entry1->group, group2 = entry2->group;
|
||||
/* First, compare the group numbers. For entries within a cluster, what
|
||||
matters is the group number of the base cluster in which the entry
|
||||
resides. */
|
||||
int group1 = (entry1->cluster
|
||||
? hol_cluster_base (entry1->cluster)->group
|
||||
: entry1->group);
|
||||
int group2 = (entry2->cluster
|
||||
? hol_cluster_base (entry2->cluster)->group
|
||||
: entry2->group);
|
||||
int cmp = group_cmp (group1, group2);
|
||||
if (cmp != 0)
|
||||
return cmp;
|
||||
|
||||
if (entry1->cluster != entry2->cluster)
|
||||
/* The group numbers are the same. */
|
||||
|
||||
/* Entries that are not in a cluster come before entries in a cluster. */
|
||||
cmp = (entry1->cluster != NULL) - (entry2->cluster != NULL);
|
||||
if (cmp != 0)
|
||||
return cmp;
|
||||
|
||||
/* Compare the clusters. */
|
||||
if (entry1->cluster != NULL)
|
||||
{
|
||||
/* The entries are not within the same cluster, so we can't compare them
|
||||
directly, we have to use the appropriate clustering level too. */
|
||||
if (! entry1->cluster)
|
||||
/* ENTRY1 is at the `base level', not in a cluster, so we have to
|
||||
compare it's group number with that of the base cluster in which
|
||||
ENTRY2 resides. Note that if they're in the same group, the
|
||||
clustered option always comes last. */
|
||||
return group_cmp (group1, hol_cluster_base (entry2->cluster)->group, -1);
|
||||
else if (! entry2->cluster)
|
||||
/* Likewise, but ENTRY2's not in a cluster. */
|
||||
return group_cmp (hol_cluster_base (entry1->cluster)->group, group2, 1);
|
||||
else
|
||||
/* Both entries are in clusters, we can just compare the clusters. */
|
||||
return hol_cluster_cmp (entry1->cluster, entry2->cluster);
|
||||
cmp = hol_cluster_cmp (entry1->cluster, entry2->cluster);
|
||||
if (cmp != 0)
|
||||
return cmp;
|
||||
}
|
||||
else if (group1 == group2)
|
||||
/* The entries are both in the same cluster and group, so compare them
|
||||
alphabetically. */
|
||||
{
|
||||
int short1 = hol_entry_first_short (entry1);
|
||||
int short2 = hol_entry_first_short (entry2);
|
||||
int doc1 = odoc (entry1->opt);
|
||||
int doc2 = odoc (entry2->opt);
|
||||
|
||||
/* For entries in the same cluster, compare also the group numbers
|
||||
within the cluster. */
|
||||
cmp = group_cmp (entry1->group, entry2->group);
|
||||
if (cmp != 0)
|
||||
return cmp;
|
||||
|
||||
/* The entries are both in the same group and the same cluster. */
|
||||
|
||||
/* 'documentation' options always follow normal options (or documentation
|
||||
options that *look* like normal options). */
|
||||
const char *long1 = hol_entry_first_long (entry1);
|
||||
const char *long2 = hol_entry_first_long (entry2);
|
||||
int doc1 =
|
||||
(odoc (entry1->opt) ? long1 != NULL && canon_doc_option (&long1) : 0);
|
||||
int doc2 =
|
||||
(odoc (entry2->opt) ? long2 != NULL && canon_doc_option (&long2) : 0);
|
||||
cmp = doc1 - doc2;
|
||||
if (cmp != 0)
|
||||
return cmp;
|
||||
|
||||
if (doc1)
|
||||
doc1 = long1 != NULL && canon_doc_option (&long1);
|
||||
if (doc2)
|
||||
doc2 = long2 != NULL && canon_doc_option (&long2);
|
||||
/* Compare the entries alphabetically. */
|
||||
|
||||
if (doc1 != doc2)
|
||||
/* `documentation' options always follow normal options (or
|
||||
documentation options that *look* like normal options). */
|
||||
return doc1 - doc2;
|
||||
else if (!short1 && !short2 && long1 && long2)
|
||||
/* Only long options. */
|
||||
return __strcasecmp (long1, long2);
|
||||
else
|
||||
/* Compare short/short, long/short, short/long, using the first
|
||||
character of long options. Entries without *any* valid
|
||||
options (such as options with OPTION_HIDDEN set) will be put
|
||||
first, but as they're not displayed, it doesn't matter where
|
||||
they are. */
|
||||
/* First, compare the first character of the options.
|
||||
Put entries without *any* valid options (such as options with
|
||||
OPTION_HIDDEN set) first. But as they're not displayed, it doesn't
|
||||
matter where they are. */
|
||||
int short1 = hol_entry_first_short (entry1);
|
||||
int short2 = hol_entry_first_short (entry2);
|
||||
unsigned char first1 = short1 ? short1 : long1 != NULL ? *long1 : 0;
|
||||
unsigned char first2 = short2 ? short2 : long2 != NULL ? *long2 : 0;
|
||||
/* Compare ignoring case. */
|
||||
/* Use tolower, not _tolower, since the latter has undefined behaviour
|
||||
for characters that are not uppercase letters. */
|
||||
cmp = tolower (first1) - tolower (first2);
|
||||
if (cmp != 0)
|
||||
return cmp;
|
||||
/* When the options start with the same letter (ignoring case), lower-case
|
||||
comes first. */
|
||||
cmp = first2 - first1;
|
||||
if (cmp != 0)
|
||||
return cmp;
|
||||
|
||||
/* The first character of the options agree. */
|
||||
|
||||
/* Put entries with a short option before entries without a short option. */
|
||||
cmp = (short1 != 0) - (short2 != 0);
|
||||
if (cmp != 0)
|
||||
return cmp;
|
||||
|
||||
/* Compare entries without a short option by comparing the long option. */
|
||||
if (short1 == 0)
|
||||
{
|
||||
unsigned char first1 = short1 ? short1 : long1 ? *long1 : 0;
|
||||
unsigned char first2 = short2 ? short2 : long2 ? *long2 : 0;
|
||||
/* Use tolower, not _tolower, since the latter has undefined
|
||||
behaviour for characters that are not uppercase letters. */
|
||||
int lower_cmp = tolower (first1) - tolower (first2);
|
||||
/* Compare ignoring case, except when the options are both the
|
||||
same letter, in which case lower-case always comes first. */
|
||||
return lower_cmp ? lower_cmp : first2 - first1;
|
||||
cmp = (long1 != NULL) - (long2 != NULL);
|
||||
if (cmp != 0)
|
||||
return cmp;
|
||||
|
||||
if (long1 != NULL)
|
||||
{
|
||||
cmp = __strcasecmp (long1, long2);
|
||||
if (cmp != 0)
|
||||
return cmp;
|
||||
}
|
||||
}
|
||||
else
|
||||
/* Within the same cluster, but not the same group, so just compare
|
||||
groups. */
|
||||
return group_cmp (group1, group2, 0);
|
||||
|
||||
/* We're out of comparison criteria. At this point, if ENTRY1 != ENTRY2,
|
||||
the order of these entries will be unpredictable. */
|
||||
return 0;
|
||||
}
|
||||
|
||||
/* Variant of hol_entry_cmp with correct signature for qsort. */
|
||||
|
||||
Loading…
Reference in New Issue
Block a user