Hi Ævar
On 08/07/2022 15:20, Ævar Arnfjörð Bjarmason wrote:
Use the newly created GCALLOC_ARRAY() helpers rather than the recently
introduced XDL_[C]ALLOC_ARRAY().
As shown in this diff the calling convention differs, we cannot use
GCALLOC_ARRAY() as an expression, but that's an advantage in not
having to relay the "sizeof()" down via a wrapper function.
This also:
* Fixes long-standing potential overflow issues, as we're using
st_mult() in the underlying G_[C]ALLOC(). Note that the
What issues is this fixing? XDL_ALLOC_ARRAY() already checks for overflow.
* Slightly optimizes the "XDL_CALLOC_ARRAY", as we'll now use
calloc() rather than malloc() + memset() (although smart compilers
will probably do the same for both...).
That's addressed in V2 of my series, unfortunately I sent it just after
you'd sent this series.
* Changes the "XDL_CALLOC_ARRAY" behavior where we'd shortcut if the
size was already large enough, but this behavior was changed when
XDL_ALLOC_ARRAY() was introduced, so this is safe.
I'm not sure what you mean here - how did we shortcut before?
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@xxxxxxxxx>
---
xdiff/xdiffi.c | 3 ++-
xdiff/xhistogram.c | 9 ++++++---
xdiff/xmacros.h | 12 ------------
xdiff/xpatience.c | 6 ++++--
xdiff/xprepare.c | 24 ++++++++++++++++--------
5 files changed, 28 insertions(+), 26 deletions(-)
diff --git a/xdiff/xdiffi.c b/xdiff/xdiffi.c
index 6fded43e87d..077cc456087 100644
--- a/xdiff/xdiffi.c
+++ b/xdiff/xdiffi.c
@@ -333,7 +333,8 @@ int xdl_do_diff(mmfile_t *mf1, mmfile_t *mf2, xpparam_t const *xpp,
* One is to store the forward path and one to store the backward path.
*/
ndiags = xe->xdf1.nreff + xe->xdf2.nreff + 3;
- if (!XDL_ALLOC_ARRAY(kvd, 2 * ndiags + 2))
+ GALLOC_ARRAY(kvd, 2 * ndiags + 2);
+ if (!kvd)
return -1;
kvdf = kvd;
kvdb = kvdf + ndiags;
diff --git a/xdiff/xhistogram.c b/xdiff/xhistogram.c
index df909004c10..f20592bfbdd 100644
--- a/xdiff/xhistogram.c
+++ b/xdiff/xhistogram.c
@@ -266,14 +266,17 @@ static int find_lcs(xpparam_t const *xpp, xdfenv_t *env,
index.table_bits = xdl_hashbits(count1);
index.records_size = 1 << index.table_bits;
- if (!XDL_CALLOC_ARRAY(index.records, index.records_size))
+ GCALLOC_ARRAY(index.records, index.records_size);
+ if (!index.records)
I don't think that having GALLOC_ARRAY() as a statement is an
improvement here.
Best Wishes
Phillip
goto cleanup;
index.line_map_size = count1;
- if (!XDL_CALLOC_ARRAY(index.line_map, index.line_map_size))
+ GCALLOC_ARRAY(index.line_map, index.line_map_size);
+ if (!index.line_map)
goto cleanup;
- if (!XDL_CALLOC_ARRAY(index.next_ptrs, index.line_map_size))
+ GCALLOC_ARRAY(index.next_ptrs, index.line_map_size);
+ if (!index.next_ptrs)
goto cleanup;
/* lines / 4 + 1 comes from xprepare.c:xdl_prepare_ctx() */
diff --git a/xdiff/xmacros.h b/xdiff/xmacros.h
index d13a6724629..75506bdf17e 100644
--- a/xdiff/xmacros.h
+++ b/xdiff/xmacros.h
@@ -49,18 +49,6 @@ do { \
((unsigned long) __p[2]) << 16 | ((unsigned long) __p[3]) << 24; \
} while (0)
-/* Allocate an array of nr elements, returns NULL on failure */
-#define XDL_ALLOC_ARRAY(p, nr) \
- ((p) = SIZE_MAX / sizeof(*(p)) >= (size_t)(nr) \
- ? xdl_malloc((nr) * sizeof(*(p))) \
- : NULL)
-
-/* Allocate an array of nr zeroed out elements, returns NULL on failure */
-#define XDL_CALLOC_ARRAY(p, nr) \
- (XDL_ALLOC_ARRAY((p), (nr)) \
- ? memset((p), 0, (nr) * sizeof(*(p))) \
- : NULL)
-
/*
* Ensure array p can accommodate at least nr elements, growing the
* array and updating alloc (which is the number of allocated
diff --git a/xdiff/xpatience.c b/xdiff/xpatience.c
index fe39c2978cb..bb328d9f852 100644
--- a/xdiff/xpatience.c
+++ b/xdiff/xpatience.c
@@ -151,7 +151,8 @@ static int fill_hashmap(mmfile_t *file1, mmfile_t *file2,
/* We know exactly how large we want the hash map */
result->alloc = count1 * 2;
- if (!XDL_CALLOC_ARRAY(result->entries, result->alloc))
+ GCALLOC_ARRAY(result->entries, result->alloc);
+ if (!result->entries)
return -1;
/* First, fill with entries from the first file */
@@ -208,7 +209,8 @@ static int find_longest_common_sequence(struct hashmap *map, struct entry **res)
*/
int anchor_i = -1;
- if (!XDL_ALLOC_ARRAY(sequence, map->nr))
+ GALLOC_ARRAY(sequence, map->nr);
+ if (!sequence)
return -1;
for (entry = map->first; entry; entry = entry->next) {
diff --git a/xdiff/xprepare.c b/xdiff/xprepare.c
index c84549f6c50..d6cbee32a2a 100644
--- a/xdiff/xprepare.c
+++ b/xdiff/xprepare.c
@@ -78,15 +78,17 @@ static int xdl_init_classifier(xdlclassifier_t *cf, long size, long flags) {
return -1;
}
- if (!XDL_CALLOC_ARRAY(cf->rchash, cf->hsize)) {
+ GCALLOC_ARRAY(cf->rchash, cf->hsize);
+ if (!cf->rchash) {
xdl_cha_free(&cf->ncha);
return -1;
}
cf->alloc = size;
- if (!XDL_ALLOC_ARRAY(cf->rcrecs, cf->alloc)) {
+ GALLOC_ARRAY(cf->rcrecs, cf->alloc);
+ if (!cf->rcrecs) {
xdl_free(cf->rchash);
xdl_cha_free(&cf->ncha);
return -1;
@@ -170,12 +172,14 @@ static int xdl_prepare_ctx(unsigned int pass, mmfile_t *mf, long narec, xpparam_
if (xdl_cha_init(&xdf->rcha, sizeof(xrecord_t), narec / 4 + 1) < 0)
goto abort;
- if (!XDL_ALLOC_ARRAY(recs, narec))
+ GALLOC_ARRAY(recs, narec);
+ if (!recs)
goto abort;
hbits = xdl_hashbits((unsigned int) narec);
hsize = 1 << hbits;
- if (!XDL_CALLOC_ARRAY(rhash, hsize))
+ GCALLOC_ARRAY(rhash, hsize);
+ if (!rhash)
goto abort;
nrec = 0;
@@ -196,14 +200,17 @@ static int xdl_prepare_ctx(unsigned int pass, mmfile_t *mf, long narec, xpparam_
}
}
- if (!XDL_CALLOC_ARRAY(rchg, nrec + 2))
+ GCALLOC_ARRAY(rchg, nrec + 2);
+ if (!rchg)
goto abort;
if ((XDF_DIFF_ALG(xpp->flags) != XDF_PATIENCE_DIFF) &&
(XDF_DIFF_ALG(xpp->flags) != XDF_HISTOGRAM_DIFF)) {
- if (!XDL_ALLOC_ARRAY(rindex, nrec + 1))
+ GALLOC_ARRAY(rindex, nrec + 1);
+ if (!rindex)
goto abort;
- if (!XDL_ALLOC_ARRAY(ha, nrec + 1))
+ GALLOC_ARRAY(ha, nrec + 1);
+ if (!ha)
goto abort;
}
@@ -369,7 +376,8 @@ static int xdl_cleanup_records(xdlclassifier_t *cf, xdfile_t *xdf1, xdfile_t *xd
xdlclass_t *rcrec;
char *dis, *dis1, *dis2;
- if (!XDL_CALLOC_ARRAY(dis, xdf1->nrec + xdf2->nrec + 2))
+ GCALLOC_ARRAY(dis, xdf1->nrec + xdf2->nrec + 2);
+ if (!dis)
return -1;
dis1 = dis;
dis2 = dis1 + xdf1->nrec + 1;
