diff options
author | Geoff Thorpe <geoff@openssl.org> | 2000-06-01 02:15:40 +0000 |
---|---|---|
committer | Geoff Thorpe <geoff@openssl.org> | 2000-06-01 02:15:40 +0000 |
commit | 7bb7043580900b8f06cb418b46004b755ff0fc96 (patch) | |
tree | 2c7daae78031c2b18e2ecd27473b57f8a3bef121 /crypto/stack/stack.c | |
parent | f3e9b338e0badedc87f6014bdbb8594e5af00acd (diff) |
This is the first of two commits (didn't want to dump them all into the
same one). However, the first will temporarily break things until the
second comes through. :-)
The safestack.h handling was mapping compare callbacks that externally
are of the type (int (*)(type **,type **)) into the underlying callback
type used by stack.[ch], which is (int (*)(void *,void *)). After some
degree of digging, it appears that the callback type in the underlying
stack code should use double pointers too - when the compare operations
are invoked (from sk_find and sk_sort), they are being used by bsearch
and qsort to compare two pointers to pointers. This change corrects the
prototyping (by only casting to the (void*,void*) form at the moment
it is needed by bsearch and qsort) and makes the mapping in safestack.h
more transparent. It also changes from "void*" to "char*" to stay in
keeping with stack.[ch]'s assumed base type of "char".
Also - the "const" situation was that safestack.h was throwing away
"const"s, and to compound the problem - a close examination of stack.c
showed that (const char **) is not really achieving what it is supposed
to when the callback is being invoked, what is needed is
(const char * const *). So the underlying stack.[ch] and the mapping
macros in safestack.h have all been altered to correct this.
What will follow are the vast quantities of "const" corrections required
in stack-dependant code that was being let "slip" through when
safestack.h was discarding "const"s. These now all come up as compiler
warnings.
Diffstat (limited to 'crypto/stack/stack.c')
-rw-r--r-- | crypto/stack/stack.c | 29 |
1 files changed, 23 insertions, 6 deletions
diff --git a/crypto/stack/stack.c b/crypto/stack/stack.c index be132d5dea..8f57daa6f4 100644 --- a/crypto/stack/stack.c +++ b/crypto/stack/stack.c @@ -76,9 +76,10 @@ const char *STACK_version="Stack" OPENSSL_VERSION_PTEXT; #include <errno.h> -int (*sk_set_cmp_func(STACK *sk, int (*c)(const void *,const void *)))(const void *, const void *) +int (*sk_set_cmp_func(STACK *sk, int (*c)(const char * const *,const char * const *))) + (const char * const *, const char * const *) { - int (*old)(const void *,const void *)=sk->comp; + int (*old)(const char * const *,const char * const *)=sk->comp; if (sk->comp != c) sk->sorted=0; @@ -108,7 +109,7 @@ err: return(NULL); } -STACK *sk_new(int (*c)(const void *, const void *)) +STACK *sk_new(int (*c)(const char * const *, const char * const *)) { STACK *ret; int i; @@ -218,13 +219,24 @@ int sk_find(STACK *st, char *data) } sk_sort(st); if (data == NULL) return(-1); - comp_func=st->comp; + /* This (and the "qsort" below) are the two places in OpenSSL + * where we need to convert from our standard (type **,type **) + * compare callback type to the (void *,void *) type required by + * bsearch. However, the "data" it is being called(back) with are + * not (type *) pointers, but the *pointers* to (type *) pointers, + * so we get our extra level of pointer dereferencing that way. */ + comp_func=(int (*)(const void *,const void *))(st->comp); r=(char **)bsearch(&data,(char *)st->data, st->num,sizeof(char *), comp_func); if (r == NULL) return(-1); i=(int)(r-st->data); for ( ; i>0; i--) - if ((*st->comp)(&(st->data[i-1]),&data) < 0) + /* This needs a cast because the type being pointed to from + * the "&" expressions are (char *) rather than (const char *). + * For an explanation, read: + * http://www.eskimo.com/~scs/C-faq/q11.10.html :-) */ + if ((*st->comp)((const char * const *)&(st->data[i-1]), + (const char * const *)&data) < 0) break; return(i); } @@ -303,7 +315,12 @@ void sk_sort(STACK *st) { int (*comp_func)(const void *,const void *); - comp_func=st->comp; + /* same comment as in sk_find ... previously st->comp was declared + * as a (void*,void*) callback type, but this made the population + * of the callback pointer illogical - our callbacks compare + * type** with type**, so we leave the casting until absolutely + * necessary (ie. "now"). */ + comp_func=(int (*)(const void *,const void *))(st->comp); qsort(st->data,st->num,sizeof(char *), comp_func); st->sorted=1; } |