From 7bb7043580900b8f06cb418b46004b755ff0fc96 Mon Sep 17 00:00:00 2001 From: Geoff Thorpe Date: Thu, 1 Jun 2000 02:15:40 +0000 Subject: [PATCH 1/1] 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. --- crypto/stack/safestack.h | 24 +++++++++++++++--------- crypto/stack/stack.c | 29 +++++++++++++++++++++++------ crypto/stack/stack.h | 12 +++++++----- 3 files changed, 45 insertions(+), 20 deletions(-) diff --git a/crypto/stack/safestack.h b/crypto/stack/safestack.h index da631581f6..6a093201dc 100644 --- a/crypto/stack/safestack.h +++ b/crypto/stack/safestack.h @@ -65,7 +65,8 @@ STACK_OF(type) \ { \ STACK stack; \ }; \ -STACK_OF(type) *sk_##type##_new(int (*cmp)(type **,type **)); \ +STACK_OF(type) *sk_##type##_new(int (*cmp)(const type * const *, \ + const type * const *)); \ STACK_OF(type) *sk_##type##_new_null(void); \ void sk_##type##_free(STACK_OF(type) *sk); \ int sk_##type##_num(const STACK_OF(type) *sk); \ @@ -76,10 +77,11 @@ int sk_##type##_push(STACK_OF(type) *sk,type *v); \ int sk_##type##_unshift(STACK_OF(type) *sk,type *v); \ int sk_##type##_find(STACK_OF(type) *sk,type *v); \ type *sk_##type##_delete(STACK_OF(type) *sk,int n); \ -void sk_##type##_delete_ptr(STACK_OF(type) *sk,type *v); \ +type *sk_##type##_delete_ptr(STACK_OF(type) *sk,type *v); \ int sk_##type##_insert(STACK_OF(type) *sk,type *v,int n); \ int (*sk_##type##_set_cmp_func(STACK_OF(type) *sk, \ - int (*cmp)(type **,type **)))(type **,type **); \ + int (*cmp)(const type * const *,const type * const *))) \ + (const type * const *,const type * const *); \ STACK_OF(type) *sk_##type##_dup(STACK_OF(type) *sk); \ void sk_##type##_pop_free(STACK_OF(type) *sk,void (*func)(type *)); \ type *sk_##type##_shift(STACK_OF(type) *sk); \ @@ -87,8 +89,10 @@ type *sk_##type##_pop(STACK_OF(type) *sk); \ void sk_##type##_sort(STACK_OF(type) *sk); #define IMPLEMENT_STACK_OF(type) \ -STACK_OF(type) *sk_##type##_new(int (*cmp)(type **,type **)) \ - { return (STACK_OF(type) *)sk_new((int (*)())cmp); } \ +STACK_OF(type) *sk_##type##_new(int (*cmp)(const type * const *, \ + const type * const *)) \ + { return (STACK_OF(type) *)sk_new( \ + (int (*)(const char * const *,const char * const *))cmp); } \ STACK_OF(type) *sk_##type##_new_null() \ { return (STACK_OF(type) *)sk_new_null(); } \ void sk_##type##_free(STACK_OF(type) *sk) \ @@ -109,13 +113,15 @@ int sk_##type##_find(STACK_OF(type) *sk,type *v) \ { return sk_find((STACK *)sk,(char *)v); } \ type *sk_##type##_delete(STACK_OF(type) *sk,int n) \ { return (type *)sk_delete((STACK *)sk,n); } \ -void sk_##type##_delete_ptr(STACK_OF(type) *sk,type *v) \ - { sk_delete_ptr((STACK *)sk,(char *)v); } \ +type *sk_##type##_delete_ptr(STACK_OF(type) *sk,type *v) \ + { return (type *)sk_delete_ptr((STACK *)sk,(char *)v); } \ int sk_##type##_insert(STACK_OF(type) *sk,type *v,int n) \ { return sk_insert((STACK *)sk,(char *)v,n); } \ int (*sk_##type##_set_cmp_func(STACK_OF(type) *sk, \ - int (*cmp)(type **,type **)))(type **,type **) \ - { return (int (*)(type **,type **))sk_set_cmp_func((STACK *)sk,(int(*)(const void *, const void *))cmp); } \ + int (*cmp)(const type * const *,const type * const *))) \ + (const type * const *,const type * const *) \ + { return (int (*)(const type * const *,const type * const *))sk_set_cmp_func( \ + (STACK *)sk, (int(*)(const char * const *, const char * const *))cmp); } \ STACK_OF(type) *sk_##type##_dup(STACK_OF(type) *sk) \ { return (STACK_OF(type) *)sk_dup((STACK *)sk); } \ void sk_##type##_pop_free(STACK_OF(type) *sk,void (*func)(type *)) \ 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 -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; } diff --git a/crypto/stack/stack.h b/crypto/stack/stack.h index 1613ac5fb1..6f5b4bdce2 100644 --- a/crypto/stack/stack.h +++ b/crypto/stack/stack.h @@ -70,11 +70,11 @@ typedef struct stack_st int sorted; int num_alloc; - int (*comp)(const void *, const void *); + int (*comp)(const char * const *, const char * const *); } STACK; - -#define sk_new_null() sk_new(NULL) +#define sk_new_null() sk_new((int (*)(const char * const *, \ + const char * const *))NULL) #define M_sk_num(sk) ((sk) ? (sk)->num:-1) #define M_sk_value(sk,n) ((sk) ? (sk)->data[n] : NULL) @@ -84,7 +84,7 @@ char *sk_value(const STACK *, int); char *sk_set(STACK *, int, char *); -STACK *sk_new(int (*cmp)(const void *, const void *)); +STACK *sk_new(int (*cmp)(const char * const *, const char * const *)); void sk_free(STACK *); void sk_pop_free(STACK *st, void (*func)(void *)); int sk_insert(STACK *sk,char *data,int where); @@ -96,7 +96,9 @@ int sk_unshift(STACK *st,char *data); char *sk_shift(STACK *st); char *sk_pop(STACK *st); void sk_zero(STACK *st); -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 *); STACK *sk_dup(STACK *st); void sk_sort(STACK *st); -- 2.34.1