]> git.sur5r.net Git - openldap/blobdiff - servers/slapd/entry.c
Fixup bdb_entry_release now that entry_decode uses two memory blocks
[openldap] / servers / slapd / entry.c
index a150097dae6754c7d7dcdd55723427bc4b6188be..c4d49baec1288a90ae7b440050033e4b3b385189 100644 (file)
@@ -41,7 +41,6 @@ str2entry( char *s )
 {
        int rc;
        Entry           *e;
-       Attribute       **a = NULL;
        char            *type;
        struct berval value;
        struct berval   *vals[2];
@@ -385,26 +384,72 @@ entry_id_cmp( Entry *e1, Entry *e2 )
 
 #ifdef SLAPD_BDB
 
-/* Flatten an Entry into a buffer. The buffer contents become a direct
- * copy of the entry, with all pointers converted to offsets from the
- * beginning of the buffer. We do this by first walking through all
- * the fields of the Entry, adding up their sizes. Then a single chunk
- * of memory is malloc'd and the entry is copied. We differentiate between
- * fixed size fields and variable-length content when tallying up the
- * entry size, so that we can stick all of the variable-length stuff
- * into the back half of the buffer.
+/* This is like a ber_len */
+static ber_len_t
+entry_lenlen(ber_len_t len)
+{
+       if (len <= 0x7f)
+               return 1;
+       if (len <= 0xff)
+               return 2;
+       if (len <= 0xffff)
+               return 3;
+       if (len <= 0xffffff)
+               return 4;
+       return 5;
+}
+
+static void
+entry_putlen(unsigned char **buf, ber_len_t len)
+{
+       ber_len_t lenlen = entry_lenlen(len);
+
+       if (lenlen == 1) {
+               **buf = (unsigned char) len;
+       } else {
+               int i;
+               **buf = 0x80 | (lenlen - 1);
+               for (i=lenlen-1; i>0; i--) {
+                       (*buf)[i] = (unsigned char) len;
+                       len >>= 8;
+               }
+       }
+       *buf += lenlen;
+}
+
+static ber_len_t
+entry_getlen(unsigned char **buf)
+{
+       ber_len_t len;
+       int i;
+
+       len = *(*buf)++;
+       if (len <= 0x7f)
+               return len;
+       i = len & 0x7f;
+       len = 0;
+       for (;i > 0; i--) {
+               len <<= 8;
+               len |= *(*buf)++;
+       }
+       return len;
+}
+
+/* Flatten an Entry into a buffer. The buffer is filled with just the
+ * strings/bervals of all the entry components. Each field is preceded
+ * by its length, encoded the way ber_put_len works. Every field is NUL
+ * terminated.  The entire buffer size is precomputed so that a single
+ * malloc can be performed. The entry size is also recorded,
+ * to aid in entry_decode.
  */
-int entry_encode(Entry *e, struct berval **bv)
+int entry_encode(Entry *e, struct berval *bv)
 {
        int siz = sizeof(Entry);
        int len, dnlen, ndnlen;
-       int i, j;
-       Entry *f;
-       Attribute *a, *b;
-       struct berval **bvl, *bz;
-       char *ptr, *base, *data;
+       int i;
+       Attribute *a;
+       unsigned char *ptr;
 
-       *bv = ch_malloc(sizeof(struct berval));
 #ifdef NEW_LOGGING
        LDAP_LOG(( "operation", LDAP_LEVEL_DETAIL1,
                "entry_encode: id: 0x%08lx  \"%s\"\n",
@@ -416,81 +461,65 @@ int entry_encode(Entry *e, struct berval **bv)
        dnlen = strlen(e->e_dn);
        ndnlen = strlen(e->e_ndn);
        len = dnlen + ndnlen + 2;       /* two trailing NUL bytes */
+       len += entry_lenlen(dnlen);
+       len += entry_lenlen(ndnlen);
        for (a=e->e_attrs; a; a=a->a_next) {
                /* For AttributeDesc, we only store the attr name */
                siz += sizeof(Attribute);
                len += a->a_desc->ad_cname.bv_len+1;
+               len += entry_lenlen(a->a_desc->ad_cname.bv_len);
                for (i=0; a->a_vals[i]; i++) {
                        siz += sizeof(struct berval *);
                        siz += sizeof(struct berval);
                        len += a->a_vals[i]->bv_len + 1;
+                       len += entry_lenlen(a->a_vals[i]->bv_len);
                }
+               len += entry_lenlen(i);
                siz += sizeof(struct berval *); /* NULL pointer at end */
        }
-       (*bv)->bv_len = siz + len;
-       (*bv)->bv_val = ch_malloc(siz+len);
-       base = (*bv)->bv_val;
-       ptr = base + siz;
-       f = (Entry *)base;
-       data = (char *)(f+1);
-       f->e_id = e->e_id;
-       f->e_dn = (char *)(ptr-base);
+       len += 1;       /* NUL byte at end */
+       len += entry_lenlen(siz);
+       bv->bv_len = len;
+       bv->bv_val = ch_malloc(len);
+       ptr = (unsigned char *)bv->bv_val;
+       entry_putlen(&ptr, siz);
+       entry_putlen(&ptr, dnlen);
        memcpy(ptr, e->e_dn, dnlen);
        ptr += dnlen;
        *ptr++ = '\0';
-       f->e_ndn = (char *)(ptr-base);
+       entry_putlen(&ptr, ndnlen);
        memcpy(ptr, e->e_ndn, ndnlen);
        ptr += ndnlen;
        *ptr++ = '\0';
-       f->e_attrs = e->e_attrs ? (Attribute *)sizeof(Entry) : NULL;
-       f->e_private = NULL;
+
        for (a=e->e_attrs; a; a=a->a_next) {
-               b = (Attribute *)data;
-               data = (char *)(b+1);
-               b->a_desc = (AttributeDescription *)(ptr-base);
+               entry_putlen(&ptr, a->a_desc->ad_cname.bv_len);
                memcpy(ptr, a->a_desc->ad_cname.bv_val,
                        a->a_desc->ad_cname.bv_len);
                ptr += a->a_desc->ad_cname.bv_len;
                *ptr++ = '\0';
                if (a->a_vals) {
-                   bvl = (struct berval **)data;
-                   b->a_vals = (struct berval **)(data-base);
                    for (i=0; a->a_vals[i]; i++);
-                   data = (char *)(bvl+i+1);
-                   bz = (struct berval *)data;
-                   for (j=0; j<i; j++) {
-                           bz->bv_len = a->a_vals[j]->bv_len;
-                           if (a->a_vals[j]->bv_val) {
-                               bz->bv_val = (char *)(ptr-base);
-                               memcpy(ptr, a->a_vals[j]->bv_val, bz->bv_len);
-                           } else {
-                               bz->bv_val = NULL;
-                           }
-                           ptr += bz->bv_len;
-                           *ptr++ = '\0';
-                           bvl[j] = (struct berval *)(data-base);
-                           bz++;
-                           data = (char *)bz;
+                   entry_putlen(&ptr, i);
+                   for (i=0; a->a_vals[i]; i++) {
+                       entry_putlen(&ptr, a->a_vals[i]->bv_len);
+                       memcpy(ptr, a->a_vals[i]->bv_val,
+                               a->a_vals[i]->bv_len);
+                       ptr += a->a_vals[i]->bv_len;
+                       *ptr++ = '\0';
                    }
-                   bvl[j] = NULL;
-               } else {
-                   b->a_vals = NULL;
                }
-
-               if (a->a_next)
-                   b->a_next = (Attribute *)(data-base);
-               else
-                   b->a_next = NULL;
        }
+       *ptr = '\0';
        return 0;
 }
 
 /* Retrieve an Entry that was stored using entry_encode above.
- * All we have to do is add the buffer address to all of the
- * stored offsets. We also must lookup the stored attribute names
- * to get AttributeDescriptions. To detect if the attributes of
- * an Entry are later modified, we also store the address of the
- * end of this block in e_private.
+ * We malloc a single block with the size stored above for the Entry
+ * and all if its Attributes. We also must lookup the stored
+ * attribute names to get AttributeDescriptions. To detect if the
+ * attributes of an Entry are later modified, we note that e->e_attr
+ * is always a constant offset from (e).
  *
  * Note: everything is stored in a single contiguous block, so
  * you can not free individual attributes or names from this
@@ -498,17 +527,24 @@ int entry_encode(Entry *e, struct berval **bv)
  */
 int entry_decode(struct berval *bv, Entry **e)
 {
-       int i;
-       long base;
+       int i, j;
+       int rc;
        Attribute *a;
-       Entry *x = (Entry *)bv->bv_val;
-       char *type;
+       Entry *x;
        const char *text;
        AttributeDescription *ad;
-
-       base = (long)bv->bv_val;
-       x->e_dn += base;
-       x->e_ndn += base;
+       unsigned char *ptr = (unsigned char *)bv->bv_val;
+       struct berval **bptr;
+       struct berval *vptr;
+
+       i = entry_getlen(&ptr);
+       x = ch_malloc(i);
+       i = entry_getlen(&ptr);
+       x->e_dn = ptr;
+       ptr += i+1;
+       i = entry_getlen(&ptr);
+       x->e_ndn = ptr;
+       ptr += i+1;
 #ifdef NEW_LOGGING
        LDAP_LOG(( "operation", LDAP_LEVEL_DETAIL2,
                   "entry_decode: \"%s\"\n", x->e_dn ));
@@ -517,49 +553,67 @@ int entry_decode(struct berval *bv, Entry **e)
            "entry_decode: \"%s\"\n",
            x->e_dn, 0, 0 );
 #endif
-       x->e_private = bv->bv_val + bv->bv_len;
-       if (x->e_attrs)
-               x->e_attrs = (Attribute *)((long)x->e_attrs+base);
-       for (a=x->e_attrs; a; a=a->a_next) {
-               if (a->a_next)
-                       a->a_next = (Attribute *)((long)a->a_next+base);
+       x->e_private = bv->bv_val;
+
+       /* A valid entry must have at least one attr, so this
+        * pointer can never be NULL
+        */
+       x->e_attrs = (Attribute *)(x+1);
+       bptr = (struct berval **)x->e_attrs;
+       a = NULL;
+
+       while (i = entry_getlen(&ptr)) {
+               if (a) {
+                       a->a_next = (Attribute *)bptr;
+               }
+               a = (Attribute *)bptr;
                ad = NULL;
-               type = (char *)a->a_desc+base;
-               i = slap_str2ad( type, &ad, &text );
+               rc = slap_str2ad( ptr, &ad, &text );
 
-               if( i != LDAP_SUCCESS ) {
+               if( rc != LDAP_SUCCESS ) {
 #ifdef NEW_LOGGING
                        LDAP_LOG(( "operation", LDAP_LEVEL_INFO,
-                                  "entry_decode: str2ad(%s): %s\n", type, text ));
+                                  "entry_decode: str2ad(%s): %s\n", ptr, text ));
 #else
                        Debug( LDAP_DEBUG_TRACE,
-                               "<= entry_decode: str2ad(%s): %s\n", type, text, 0 );
+                               "<= entry_decode: str2ad(%s): %s\n", ptr, text, 0 );
 #endif
-                       i = slap_str2undef_ad( type, &ad, &text );
+                       rc = slap_str2undef_ad( ptr, &ad, &text );
 
-                       if( i != LDAP_SUCCESS ) {
+                       if( rc != LDAP_SUCCESS ) {
 #ifdef NEW_LOGGING
                                LDAP_LOG(( "operation", LDAP_LEVEL_INFO,
-                                          "entry_decode:  str2undef_ad(%s): %s\n", type, text));
+                                          "entry_decode:  str2undef_ad(%s): %s\n", ptr, text));
 #else
                                Debug( LDAP_DEBUG_ANY,
                                        "<= entry_decode: str2undef_ad(%s): %s\n",
-                                               type, text, 0 );
+                                               ptr, text, 0 );
 #endif
-                               return i;
+                               return rc;
                        }
                }
+               ptr += i + 1;
                a->a_desc = ad;
-               if (a->a_vals) {
-                       a->a_vals = (struct berval **)((long)a->a_vals+base);
-                       for (i=0; a->a_vals[i]; i++) {
-                               a->a_vals[i] = (struct berval *)
-                                       ((long)a->a_vals[i]+base);
-                               if (a->a_vals[i]->bv_val)
-                                   a->a_vals[i]->bv_val += base;
-                       }
+               bptr = (struct berval **)(a+1);
+               a->a_vals = bptr;
+               j = entry_getlen(&ptr);
+               a->a_vals[j] = NULL;
+               vptr = (struct berval *)(bptr + j + 1);
+
+               while (j) {
+                       i = entry_getlen(&ptr);
+                       *bptr = vptr;
+                       vptr->bv_len = i;
+                       vptr->bv_val = (char *)ptr;
+                       ptr += i+1;
+                       bptr++;
+                       vptr++;
+                       j--;
                }
+               bptr = (struct berval **)vptr;
        }
+       if (a)
+               a->a_next = NULL;
 #ifdef NEW_LOGGING
        LDAP_LOG(( "operation", LDAP_LEVEL_DETAIL1,
                   "entry_decode:  %s\n", x->e_dn ));