Code

data: Return the number of bytes that would have been returned.
[sysdb.git] / src / core / data.c
index 4e52133484b8e219cdef562a86a7a9991bc2279e..914946fbec6761d3e7b4345742ddbd63668106c1 100644 (file)
@@ -34,6 +34,8 @@
 #include "core/data.h"
 #include "utils/error.h"
 
+#include <assert.h>
+
 #include <errno.h>
 
 #include <inttypes.h>
 
 #include <math.h>
 
+/*
+ * Operator support maxtrix.
+ * <type1> <op> <type2> -> op_matrix[<op>][<type1>][<type2>]
+ */
+
+/* add, sub, mul, div, mod, concat */
+
+/* integer, decimal, string, datetime, binary, regex */
+
+static int op_matrix[6][6][6] = {
+       /* SDB_DATA_ADD */
+       {
+               { SDB_TYPE_INTEGER, -1, -1, -1, -1, -1 },
+               { -1, SDB_TYPE_DECIMAL, -1, -1, -1, -1 },
+               { -1, -1, -1, -1, -1, -1 },
+               { -1, -1, -1, SDB_TYPE_DATETIME, -1, -1 },
+               { -1, -1, -1, -1, -1, -1 },
+               { -1, -1, -1, -1, -1, -1 },
+       },
+
+       /* SDB_DATA_SUB */
+       {
+               { SDB_TYPE_INTEGER, -1, -1, -1, -1, -1 },
+               { -1, SDB_TYPE_DECIMAL, -1, -1, -1, -1 },
+               { -1, -1, -1, -1, -1, -1 },
+               { -1, -1, -1, SDB_TYPE_DATETIME, -1, -1 },
+               { -1, -1, -1, -1, -1, -1 },
+               { -1, -1, -1, -1, -1, -1 },
+       },
+
+       /* SDB_DATA_MUL */
+       {
+               { SDB_TYPE_INTEGER, -1, -1, SDB_TYPE_DATETIME, -1, -1 },
+               { -1, SDB_TYPE_DECIMAL, -1, SDB_TYPE_DATETIME, -1, -1 },
+               { -1, -1, -1, -1, -1, -1 },
+               { SDB_TYPE_DATETIME, SDB_TYPE_DATETIME, -1, SDB_TYPE_DATETIME, -1, -1 },
+               { -1, -1, -1, -1, -1, -1 },
+               { -1, -1, -1, -1, -1, -1 },
+       },
+
+       /* SDB_DATA_DIV */
+       {
+               { SDB_TYPE_INTEGER, -1, -1, -1, -1, -1 },
+               { -1, SDB_TYPE_DECIMAL, -1, -1, -1, -1 },
+               { -1, -1, -1, -1, -1, -1 },
+               { SDB_TYPE_DATETIME, SDB_TYPE_DATETIME, -1, SDB_TYPE_DATETIME, -1, -1 },
+               { -1, -1, -1, -1, -1, -1 },
+               { -1, -1, -1, -1, -1, -1 },
+       },
+
+       /* SDB_DATA_MOD */
+       {
+               { SDB_TYPE_INTEGER, -1, -1, -1, -1, -1 },
+               { -1, SDB_TYPE_DECIMAL, -1, -1, -1, -1 },
+               { -1, -1, -1, -1, -1, -1 },
+               { SDB_TYPE_DATETIME, SDB_TYPE_DATETIME, -1, SDB_TYPE_DATETIME, -1, -1 },
+               { -1, -1, -1, -1, -1, -1 },
+               { -1, -1, -1, -1, -1, -1 },
+       },
+
+       /* SDB_DATA_CONCAT */
+       {
+               { -1, -1, -1, -1, -1, -1 },
+               { -1, -1, -1, -1, -1, -1 },
+               { -1, -1, SDB_TYPE_STRING, -1, -1, -1 },
+               { -1, -1, -1, -1, -1, -1 },
+               { -1, -1, -1, -1, SDB_TYPE_BINARY, -1 },
+               { -1, -1, -1, -1, -1, -1 },
+       },
+};
+
 /*
  * private helper functions
  */
 
+/* this function supports in-place copies */
+static int
+copy_array_values(sdb_data_t *dst, const sdb_data_t *src, size_t elem_size)
+{
+       int type = src->type & 0xff;
+
+       if ((type == SDB_TYPE_INTEGER) || (type == SDB_TYPE_DECIMAL)) {
+               if (dst != src)
+                       memcpy(dst->data.array.values, src->data.array.values,
+                                       src->data.array.length * elem_size);
+       }
+       else if (type == SDB_TYPE_STRING) {
+               char **s = src->data.array.values;
+               char **d = dst->data.array.values;
+               size_t i;
+
+               for (i = 0; i < src->data.array.length; ++i) {
+                       d[i] = strdup(s[i]);
+                       if (! d[i])
+                               return -1;
+               }
+       }
+       else {
+               /* TODO */
+               errno = ENOTSUP;
+               return -1;
+       }
+       return 0;
+} /* copy_array_values */
+
+static void
+free_array_values(sdb_data_t *datum)
+{
+       int type = datum->type & 0xff;
+
+       if (type == SDB_TYPE_STRING) {
+               char **v = datum->data.array.values;
+               size_t i;
+
+               for (i = 0; i < datum->data.array.length; ++i) {
+                       if (v[i])
+                               free(v[i]);
+                       v[i] = NULL;
+               }
+       }
+       else if (type == SDB_TYPE_BINARY) {
+               struct {
+                       size_t length;
+                       unsigned char *datum;
+               } *v = datum->data.array.values;
+               size_t i;
+
+               for (i = 0; i < datum->data.array.length; ++i) {
+                       if (v[i].datum)
+                               free(v[i].datum);
+                       v[i].datum = NULL;
+               }
+       }
+       else if (type == SDB_TYPE_REGEX) {
+               struct {
+                       char *raw;
+                       regex_t regex;
+               } *v = datum->data.array.values;
+               size_t i;
+
+               for (i = 0; i < datum->data.array.length; ++i) {
+                       if (v[i].raw) {
+                               free(v[i].raw);
+                               regfree(&v[i].regex);
+                       }
+                       v[i].raw = NULL;
+               }
+       }
+} /* free_array_values */
+
+/* compare two arrays element-by-element returning how the first non-equal
+ * elements compare to each other */
+static int
+array_cmp(const sdb_data_t *a1, const sdb_data_t *a2)
+{
+       int type = a1->type & 0xff;
+       size_t len, i;
+
+       assert((a1->type == a2->type) && (a1->type & SDB_TYPE_ARRAY));
+
+       len = SDB_MIN(a1->data.array.length, a2->data.array.length);
+
+       if (type == SDB_TYPE_INTEGER) {
+               int64_t *v1 = a1->data.array.values;
+               int64_t *v2 = a2->data.array.values;
+
+               for (i = 0; i < len; ++i)
+                       if (v1[i] != v2[i])
+                               return SDB_CMP(v1[i], v2[i]);
+       }
+       else if (type == SDB_TYPE_DECIMAL) {
+               double *v1 = a1->data.array.values;
+               double *v2 = a2->data.array.values;
+
+               for (i = 0; i < len; ++i)
+                       if (v1[i] != v2[i])
+                               return SDB_CMP(v1[i], v2[i]);
+       }
+       else if (type == SDB_TYPE_STRING) {
+               char **v1 = a1->data.array.values;
+               char **v2 = a2->data.array.values;
+
+               for (i = 0; i < len; ++i) {
+                       int diff = strcasecmp(v1[i], v2[i]);
+                       if (diff)
+                               return diff;
+               }
+       }
+       else if (type == SDB_TYPE_DATETIME) {
+               sdb_time_t *v1 = a1->data.array.values;
+               sdb_time_t *v2 = a2->data.array.values;
+
+               for (i = 0; i < len; ++i)
+                       if (v1[i] != v2[i])
+                               return SDB_CMP(v1[i], v2[i]);
+       }
+       else if (type == SDB_TYPE_BINARY) {
+               struct {
+                       size_t length;
+                       unsigned char *datum;
+               } *v1 = a1->data.array.values;
+               struct {
+                       size_t length;
+                       unsigned char *datum;
+               } *v2 = a2->data.array.values;
+
+               for (i = 0; i < len; ++i) {
+                       int diff;
+
+                       /* on a common prefix, the shorter datum sorts less */
+                       if (v1[i].length < v2[i].length) {
+                               diff = memcmp(v1[i].datum, v2[i].datum, v1[i].length);
+                               diff = diff ? diff : -1;
+                       }
+                       else if (v1[i].length > v2[i].length) {
+                               diff = memcmp(v1[i].datum, v2[i].datum, v2[i].length);
+                               diff = diff ? diff : 1;
+                       }
+                       else
+                               diff = memcmp(v1[i].datum, v2[i].datum, v1[i].length);
+
+                       if (diff)
+                               return diff;
+               }
+       }
+       else if (type == SDB_TYPE_REGEX) {
+               struct {
+                       char *raw;
+                       regex_t regex;
+               } *v1 = a1->data.array.values;
+               struct {
+                       char *raw;
+                       regex_t regex;
+               } *v2 = a2->data.array.values;
+
+               for (i = 0; i < len; ++i) {
+                       int diff = strcasecmp(v1[i].raw, v2[i].raw);
+                       if (diff)
+                               return diff;
+               }
+       }
+       else {
+               errno = EINVAL;
+               /* but fall through to ensure stable sorting: */
+       }
+       return SDB_CMP(a1->data.array.length, a2->data.array.length);
+} /* array_cmp */
+
 /* Calculate the linear function 'd1 + n * d2'. */
 static int
 data_lin(const sdb_data_t *d1, int n, const sdb_data_t *d2, sdb_data_t *res)
@@ -179,17 +425,41 @@ static int
 data_concat(const sdb_data_t *d1, const sdb_data_t *d2, sdb_data_t *res)
 {
        unsigned char *new;
-       unsigned char *s1, *s2;
-       size_t len1, len2;
+       const unsigned char *s1, *s2;
+       size_t len1, len2, array1_len = 0, array2_len = 0;
 
-       if (d1->type != d2->type)
+       if ((d1->type & 0xff) != (d2->type & 0xff))
                return -1;
 
-       if (d1->type == SDB_TYPE_STRING) {
+       if ((d1->type & SDB_TYPE_ARRAY) || (d2->type & SDB_TYPE_ARRAY)) {
+               size_t elem_size = sdb_data_sizeof(d1->type & 0xff);
+               if (d1->type & SDB_TYPE_ARRAY) {
+                       s1 = (const unsigned char *)d1->data.array.values;
+                       array1_len = d1->data.array.length;
+               }
+               else {
+                       /* As per C99, section 6.7.2.1, paragraph 14:
+                        * "A pointer to a union object, suitably converted, points to
+                        * each of its members" */
+                       s1 = (const unsigned char *)&d1->data;
+                       array1_len = 1;
+               }
+               if (d2->type & SDB_TYPE_ARRAY) {
+                       s2 = (const unsigned char *)d2->data.array.values;
+                       array2_len = d2->data.array.length;
+               }
+               else {
+                       s2 = (const unsigned char *)&d2->data;
+                       array2_len = 1;
+               }
+               len1 = array1_len * elem_size;
+               len2 = array2_len * elem_size;
+       }
+       else if (d1->type == SDB_TYPE_STRING) {
                s1 = (unsigned char *)d1->data.string;
                s2 = (unsigned char *)d2->data.string;
-               len1 = s1 ? strlen((char *)s1) : 0;
-               len2 = s2 ? strlen((char *)s2) : 0;
+               len1 = s1 ? strlen((const char *)s1) : 0;
+               len2 = s2 ? strlen((const char *)s2) : 0;
        }
        else if (d1->type == SDB_TYPE_BINARY) {
                s1 = d1->data.binary.datum;
@@ -200,29 +470,38 @@ data_concat(const sdb_data_t *d1, const sdb_data_t *d2, sdb_data_t *res)
        else
                return -1;
 
-       if (s1 || s2) {
-               new = malloc(len1 + len2 + 1);
-               if (! new)
-                       return -1;
-       }
-       else
-               new = NULL;
+       new = malloc(len1 + len2 + 1);
+       if (! new)
+               return -1;
 
        if (len1)
                memcpy(new, s1, len1);
        if (len2)
                memcpy(new + len1, s2, len2);
-       if (new)
-               new[len1 + len2] = '\0';
+       new[len1 + len2] = '\0';
 
-       res->type = d1->type;
+       /* element types match and if either datum is an array,
+        * the result is an array as well */
+       res->type = d1->type | d2->type;
        if (res->type == SDB_TYPE_STRING) {
                res->data.string = (char *)new;
        }
-       else {
+       else if (res->type == SDB_TYPE_BINARY) {
                res->data.binary.datum = new;
                res->data.binary.length = len1 + len2;
        }
+       else if (res->type & SDB_TYPE_ARRAY) {
+               res->data.array.values = new;
+               res->data.array.length = array1_len + array2_len;
+               if (copy_array_values(res, res, sdb_data_sizeof(res->type & 0xff))) {
+                       /* this leaks already copied values but there's not much we can
+                        * do and this should only happen if we're in trouble anyway */
+                       free(new);
+                       res->data.array.values = NULL;
+                       res->data.array.length = 0;
+                       return -1;
+               }
+       }
        return 0;
 } /* data_concat */
 
@@ -230,6 +509,8 @@ data_concat(const sdb_data_t *d1, const sdb_data_t *d2, sdb_data_t *res)
  * public API
  */
 
+const sdb_data_t SDB_DATA_NULL = SDB_DATA_INIT;
+
 int
 sdb_data_copy(sdb_data_t *dst, const sdb_data_t *src)
 {
@@ -239,39 +520,49 @@ sdb_data_copy(sdb_data_t *dst, const sdb_data_t *src)
                return -1;
 
        tmp = *src;
-       switch (src->type) {
-               case SDB_TYPE_STRING:
-                       if (src->data.string) {
-                               tmp.data.string = strdup(src->data.string);
-                               if (! tmp.data.string)
-                                       return -1;
-                       }
-                       break;
-               case SDB_TYPE_BINARY:
-                       if (src->data.binary.datum) {
-                               tmp.data.binary.datum = malloc(src->data.binary.length);
-                               if (! tmp.data.binary.datum)
-                                       return -1;
-                               memcpy(tmp.data.binary.datum, src->data.binary.datum,
-                                               src->data.binary.length);
+       if (src->type == SDB_TYPE_STRING) {
+               if (src->data.string) {
+                       tmp.data.string = strdup(src->data.string);
+                       if (! tmp.data.string)
+                               return -1;
+               }
+       }
+       else if (src->type == SDB_TYPE_BINARY) {
+               if (src->data.binary.datum) {
+                       tmp.data.binary.datum = malloc(src->data.binary.length);
+                       if (! tmp.data.binary.datum)
+                               return -1;
+                       memcpy(tmp.data.binary.datum, src->data.binary.datum,
+                                       src->data.binary.length);
+               }
+       }
+       else if (src->type == SDB_TYPE_REGEX) {
+               if (src->data.re.raw) {
+                       tmp.data.re.raw = strdup(src->data.re.raw);
+                       if (! tmp.data.re.raw)
+                               return -1;
+                       /* we need to recompile because the regex might point to
+                        * dynamically allocated memory */
+                       if (regcomp(&tmp.data.re.regex, tmp.data.re.raw,
+                                               REG_EXTENDED | REG_ICASE | REG_NOSUB)) {
+                               free(tmp.data.re.raw);
+                               return -1;
                        }
-                       break;
-               case SDB_TYPE_REGEX:
-                       if (src->data.re.raw) {
-                               tmp.data.re.raw = strdup(src->data.re.raw);
-                               if (! tmp.data.re.raw)
-                                       return -1;
-                               /* we need to recompile because the regex might point to
-                                * dynamically allocated memory */
-                               if (regcomp(&tmp.data.re.regex, tmp.data.re.raw,
-                                                       REG_EXTENDED | REG_ICASE | REG_NOSUB)) {
-                                       free(tmp.data.re.raw);
-                                       return -1;
-                               }
+               }
+               else
+                       memset(&tmp.data.re.regex, 0, sizeof(tmp.data.re.regex));
+       }
+       else if (src->type & SDB_TYPE_ARRAY) {
+               if (src->data.array.values) {
+                       size_t elem_size = sdb_data_sizeof(src->type & 0xff);
+                       tmp.data.array.values = calloc(src->data.array.length, elem_size);
+                       if (! tmp.data.array.values)
+                               return -1;
+                       if (copy_array_values(&tmp, src, elem_size)) {
+                               sdb_data_free_datum(&tmp);
+                               return -1;
                        }
-                       else
-                               memset(&tmp.data.re.regex, 0, sizeof(tmp.data.re.regex));
-                       break;
+               }
        }
 
        sdb_data_free_datum(dst);
@@ -285,26 +576,31 @@ sdb_data_free_datum(sdb_data_t *datum)
        if (! datum)
                return;
 
-       switch (datum->type) {
-               case SDB_TYPE_STRING:
-                       if (datum->data.string)
-                               free(datum->data.string);
-                       datum->data.string = NULL;
-                       break;
-               case SDB_TYPE_BINARY:
-                       if (datum->data.binary.datum)
-                               free(datum->data.binary.datum);
-                       datum->data.binary.datum = NULL;
-                       datum->data.binary.length = 0;
-                       break;
-               case SDB_TYPE_REGEX:
-                       if (datum->data.re.raw) {
-                               free(datum->data.re.raw);
-                               regfree(&datum->data.re.regex);
-                       }
-                       datum->data.re.raw = NULL;
-                       memset(&datum->data.re.regex, 0, sizeof(datum->data.re.regex));
-                       break;
+       if (datum->type == SDB_TYPE_STRING) {
+               if (datum->data.string)
+                       free(datum->data.string);
+               datum->data.string = NULL;
+       }
+       else if (datum->type == SDB_TYPE_BINARY) {
+               if (datum->data.binary.datum)
+                       free(datum->data.binary.datum);
+               datum->data.binary.datum = NULL;
+               datum->data.binary.length = 0;
+       }
+       else if (datum->type == SDB_TYPE_REGEX) {
+               if (datum->data.re.raw) {
+                       free(datum->data.re.raw);
+                       regfree(&datum->data.re.regex);
+               }
+               datum->data.re.raw = NULL;
+               memset(&datum->data.re.regex, 0, sizeof(datum->data.re.regex));
+       }
+       else if (datum->type & SDB_TYPE_ARRAY) {
+               free_array_values(datum);
+               if (datum->data.array.values)
+                       free(datum->data.array.values);
+               datum->data.array.values = NULL;
+               datum->data.array.length = 0;
        }
 } /* sdb_data_free_datum */
 
@@ -323,42 +619,45 @@ sdb_data_cmp(const sdb_data_t *d1, const sdb_data_t *d2)
        if (d1->type != d2->type)
                return SDB_CMP(d1->type, d2->type);
 
-       switch (d1->type) {
-               case SDB_TYPE_INTEGER:
-                       return SDB_CMP(d1->data.integer, d2->data.integer);
-               case SDB_TYPE_DECIMAL:
-                       return SDB_CMP(d1->data.decimal, d2->data.decimal);
-               case SDB_TYPE_STRING:
-                       CMP_NULL(d1->data.string, d2->data.string);
-                       return strcasecmp(d1->data.string, d2->data.string);
-               case SDB_TYPE_DATETIME:
-                       return SDB_CMP(d1->data.datetime, d2->data.datetime);
-               case SDB_TYPE_BINARY:
-               {
-                       int diff;
-
-                       CMP_NULL(d1->data.binary.datum, d2->data.binary.datum);
+       if (d1->type == SDB_TYPE_INTEGER)
+               return SDB_CMP(d1->data.integer, d2->data.integer);
+       else if (d1->type == SDB_TYPE_DECIMAL)
+               return SDB_CMP(d1->data.decimal, d2->data.decimal);
+       else if (d1->type == SDB_TYPE_STRING) {
+               CMP_NULL(d1->data.string, d2->data.string);
+               return strcasecmp(d1->data.string, d2->data.string);
+       }
+       else if (d1->type == SDB_TYPE_DATETIME)
+               return SDB_CMP(d1->data.datetime, d2->data.datetime);
+       else if (d1->type == SDB_TYPE_BINARY) {
+               int diff;
 
-                       /* on a common prefix, the shorter datum sorts less */
-                       if (d1->data.binary.length < d2->data.binary.length) {
-                               diff = memcmp(d1->data.binary.datum, d2->data.binary.datum,
-                                               d1->data.binary.length);
-                               diff = diff ? diff : -1;
-                       }
-                       else if (d1->data.binary.length > d2->data.binary.length) {
-                               diff = memcmp(d1->data.binary.datum, d2->data.binary.datum,
-                                               d2->data.binary.length);
-                               diff = diff ? diff : 1;
-                       }
-                       else
-                               diff = memcmp(d1->data.binary.datum, d2->data.binary.datum,
-                                               d1->data.binary.length);
+               CMP_NULL(d1->data.binary.datum, d2->data.binary.datum);
 
-                       return diff;
+               /* on a common prefix, the shorter datum sorts less */
+               if (d1->data.binary.length < d2->data.binary.length) {
+                       diff = memcmp(d1->data.binary.datum, d2->data.binary.datum,
+                                       d1->data.binary.length);
+                       diff = diff ? diff : -1;
                }
-               case SDB_TYPE_REGEX:
-                       CMP_NULL(d1->data.re.raw, d2->data.re.raw);
-                       return strcmp(d1->data.re.raw, d2->data.re.raw);
+               else if (d1->data.binary.length > d2->data.binary.length) {
+                       diff = memcmp(d1->data.binary.datum, d2->data.binary.datum,
+                                       d2->data.binary.length);
+                       diff = diff ? diff : 1;
+               }
+               else
+                       diff = memcmp(d1->data.binary.datum, d2->data.binary.datum,
+                                       d1->data.binary.length);
+
+               return diff;
+       }
+       else if (d1->type == SDB_TYPE_REGEX) {
+               CMP_NULL(d1->data.re.raw, d2->data.re.raw);
+               return strcmp(d1->data.re.raw, d2->data.re.raw);
+       }
+       else if (d1->type & SDB_TYPE_ARRAY) {
+               CMP_NULL(d1->data.array.values, d2->data.array.values);
+               return array_cmp(d1, d2);
        }
        return -1;
 } /* sdb_data_cmp */
@@ -369,6 +668,12 @@ sdb_data_strcmp(const sdb_data_t *d1, const sdb_data_t *d2)
        char d1_str[sdb_data_strlen(d1) + 1];
        char d2_str[sdb_data_strlen(d2) + 1];
 
+       if ((d1->type & SDB_TYPE_ARRAY) || (d2->type & SDB_TYPE_ARRAY)) {
+               /* TODO */
+               errno = ENOTSUP;
+               return -1;
+       }
+
        if (sdb_data_isnull(d1))
                d1 = NULL;
        if (sdb_data_isnull(d2))
@@ -376,20 +681,22 @@ sdb_data_strcmp(const sdb_data_t *d1, const sdb_data_t *d2)
 
        CMP_NULL(d1, d2);
 
-       if (sdb_data_format(d1, d1_str, sizeof(d1_str), SDB_UNQUOTED) < 0)
+       if (! sdb_data_format(d1, d1_str, sizeof(d1_str), SDB_UNQUOTED))
                return SDB_CMP(sizeof(d1_str), sizeof(d2_str));
-       if (sdb_data_format(d2, d2_str, sizeof(d2_str), SDB_UNQUOTED) < 0)
+       if (! sdb_data_format(d2, d2_str, sizeof(d2_str), SDB_UNQUOTED))
                return SDB_CMP(sizeof(d1_str), sizeof(d2_str));
 
        return strcasecmp(d1_str, d2_str);
 #undef CMP_NULL
 } /* sdb_data_strcmp */
 
-_Bool
+bool
 sdb_data_isnull(const sdb_data_t *datum)
 {
        if (! datum)
                return 1;
+       if (datum->type == SDB_TYPE_NULL)
+               return 1;
        if ((datum->type == SDB_TYPE_STRING) && (! datum->data.string))
                return 1;
        if ((datum->type == SDB_TYPE_BINARY) && (! datum->data.binary.datum))
@@ -399,6 +706,100 @@ sdb_data_isnull(const sdb_data_t *datum)
        return 0;
 } /* sdb_data_isnull */
 
+bool
+sdb_data_inarray(const sdb_data_t *value, const sdb_data_t *array)
+{
+       const void *values;
+       size_t length, i;
+       int type = value->type & 0xff;
+
+       if (sdb_data_isnull(value) || sdb_data_isnull(array))
+               return 0;
+       if (! (array->type & SDB_TYPE_ARRAY))
+               return 0;
+       if ((value->type & 0xff) != (array->type & 0xff))
+               return 0;
+
+       if (value->type & SDB_TYPE_ARRAY) {
+               values = value->data.array.values;
+               length = value->data.array.length;
+       }
+       else {
+               values = &value->data;
+               length = 1;
+       }
+
+       for (i = 0; i < length; ++i) {
+               size_t j;
+
+               if (type == SDB_TYPE_INTEGER) {
+                       int64_t *v = array->data.array.values;
+                       for (j = 0; j < array->data.array.length; ++j)
+                               if (((const int64_t *)values)[i] == v[j])
+                                       break;
+               }
+               else if (type == SDB_TYPE_DECIMAL) {
+                       double *v = array->data.array.values;
+                       for (j = 0; j < array->data.array.length; ++j)
+                               if (((const double *)values)[i] == v[j])
+                                       break;
+               }
+               else if (type == SDB_TYPE_STRING) {
+                       char **v = array->data.array.values;
+                       for (j = 0; j < array->data.array.length; ++j)
+                               if (!strcasecmp(((const char * const*)values)[i], v[j]))
+                                       break;
+               }
+               else {
+                       /* TODO */
+                       errno = ENOTSUP;
+                       return 0;
+               }
+
+               if (j >= array->data.array.length)
+                       /* value not found */
+                       return 0;
+       }
+       return 1;
+} /* sdb_data_inarray */
+
+int
+sdb_data_array_get(const sdb_data_t *array, size_t i, sdb_data_t *value)
+{
+       sdb_data_t tmp = SDB_DATA_INIT;
+       int type;
+
+       if ((! array) || (! (array->type & SDB_TYPE_ARRAY)))
+               return -1;
+       if (i >= array->data.array.length)
+               return -1;
+
+       type = array->type & 0xff;
+       if (type == SDB_TYPE_INTEGER) {
+               int64_t *v = array->data.array.values;
+               tmp.data.integer = v[i];
+       }
+       else if (type == SDB_TYPE_DECIMAL) {
+               double *v = array->data.array.values;
+               tmp.data.decimal = v[i];
+       }
+       else if (type == SDB_TYPE_STRING) {
+               char **v = array->data.array.values;
+               tmp.data.string = v[i];
+       }
+       else {
+               /* TODO */
+               errno = ENOTSUP;
+               return -1;
+       }
+
+       if (value) {
+               *value = tmp;
+               value->type = type;
+       }
+       return 0;
+} /* sdb_data_array_get */
+
 int
 sdb_data_parse_op(const char *op)
 {
@@ -423,139 +824,224 @@ sdb_data_expr_eval(int op, const sdb_data_t *d1, const sdb_data_t *d2,
 {
        if ((! d1) || (! d2) || (! res))
                return -1;
+       if (sdb_data_isnull(d1) || sdb_data_isnull(d2)) {
+               *res = SDB_DATA_NULL;
+               return 0;
+       }
        switch (op) {
-               case SDB_DATA_CONCAT:
-                       return data_concat(d1, d2, res);
-               case SDB_DATA_ADD:
-                       return data_lin(d1, 1, d2, res);
-               case SDB_DATA_SUB:
-                       return data_lin(d1, -1, d2, res);
-               case SDB_DATA_MUL:
-                       return data_mul(d1, d2, res);
-               case SDB_DATA_DIV:
-                       return data_div(d1, d2, res, NULL);
-               case SDB_DATA_MOD:
-                       return data_div(d1, d2, NULL, res);
+               case SDB_DATA_CONCAT: return data_concat(d1, d2, res);
+               case SDB_DATA_ADD: return data_lin(d1, 1, d2, res);
+               case SDB_DATA_SUB: return data_lin(d1, -1, d2, res);
+               case SDB_DATA_MUL: return data_mul(d1, d2, res);
+               case SDB_DATA_DIV: return data_div(d1, d2, res, NULL);
+               case SDB_DATA_MOD: return data_div(d1, d2, NULL, res);
        }
        return -1;
 } /* sdb_data_expr_eval */
 
+int
+sdb_data_expr_type(int op, int type1, int type2)
+{
+       int types_num = (int)SDB_STATIC_ARRAY_LEN(op_matrix[0]);
+
+       assert(SDB_STATIC_ARRAY_LEN(op_matrix[0])
+                       == SDB_STATIC_ARRAY_LEN(op_matrix[0][0]));
+
+       if ((op <= 0) || (SDB_STATIC_ARRAY_LEN(op_matrix) < (size_t)op))
+               return -1;
+
+       /* arrays only support concat; element type has to match */
+       if ((type1 & SDB_TYPE_ARRAY) || (type2 & SDB_TYPE_ARRAY)) {
+               if (((type1 & 0xff) != (type2 & 0xff)) || (op != SDB_DATA_CONCAT))
+                       return -1;
+               return type1 | SDB_TYPE_ARRAY;
+       }
+       if ((type1 < 0) || (types_num < type1)
+                       || (type2 < 0) || (types_num < type2))
+               return -1;
+
+       if ((type1 == SDB_TYPE_NULL) || (type2 == SDB_TYPE_NULL))
+               return SDB_TYPE_NULL;
+       return op_matrix[op - 1][type1 - 1][type2 - 1];
+} /* sdb_data_expr_type */
+
 size_t
 sdb_data_strlen(const sdb_data_t *datum)
 {
        if (! datum)
                return 0;
 
-       switch (datum->type) {
-               case SDB_TYPE_INTEGER:
-                       /* log(64) */
-                       return 20;
-               case SDB_TYPE_DECIMAL:
-                       /* XXX: -d.dddddde+dd or -ddddd.dddddd */
-                       return 42;
-               case SDB_TYPE_STRING:
-                       if (! datum->data.string)
-                               return 8; /* "<NULL>" */
-                       /* in the worst case, each character needs to be escaped */
-                       return 2 * strlen(datum->data.string) + 2;
-               case SDB_TYPE_DATETIME:
-                       /* "YYYY-MM-DD HH:MM:SS +zzzz" */
-                       return 27;
-               case SDB_TYPE_BINARY:
-                       if (! datum->data.binary.datum)
-                               return 8; /* "<NULL>" */
-                       /* "\xNN" */
-                       return 4 * datum->data.binary.length + 2;
-               case SDB_TYPE_REGEX:
-                       if (! datum->data.re.raw)
-                               return 8; /* "<NULL>" */
-                       /* "/.../" */
-                       return strlen(datum->data.re.raw) + 4;
+       if (sdb_data_isnull(datum)) {
+               /* NULL */
+               return 4;
+       }
+       else if (datum->type == SDB_TYPE_INTEGER) {
+               /* log(64) */
+               return 20;
+       }
+       else if (datum->type == SDB_TYPE_DECIMAL) {
+               /* XXX: -d.dddddde+dd or -ddddd.dddddd */
+               return 42;
+       }
+       else if (datum->type == SDB_TYPE_STRING) {
+               if (! datum->data.string)
+                       return 6; /* NULL */
+               /* in the worst case, each character needs to be escaped */
+               return 2 * strlen(datum->data.string) + 2;
+       }
+       else if (datum->type == SDB_TYPE_DATETIME) {
+               /* "YYYY-MM-DD HH:MM:SS +zzzz" */
+               return 27;
+       }
+       else if (datum->type == SDB_TYPE_BINARY) {
+               if (! datum->data.binary.datum)
+                       return 6; /* NULL */
+               /* "\xNN" */
+               return 4 * datum->data.binary.length + 2;
+       }
+       else if (datum->type == SDB_TYPE_REGEX) {
+               if (! datum->data.re.raw)
+                       return 6; /* NULL */
+               /* "/.../" */
+               return strlen(datum->data.re.raw) + 4;
+       }
+       else if (datum->type & SDB_TYPE_ARRAY) {
+               size_t len = 2; /* [] */
+               size_t i;
+               for (i = 0; i < datum->data.array.length; ++i) {
+                       sdb_data_t v = SDB_DATA_INIT;
+                       sdb_data_array_get(datum, i, &v);
+                       len += sdb_data_strlen(&v) + 1;
+               }
+               return len;
        }
        return 0;
 } /* sdb_data_strlen */
 
-int
+size_t
 sdb_data_format(const sdb_data_t *datum, char *buf, size_t buflen, int quoted)
 {
        char tmp[sdb_data_strlen(datum) + 1];
        char *data = NULL;
-       int ret = -1;
+       bool is_null = 0;
+       size_t ret = 0;
 
        size_t i, pos;
 
-       if ((! datum) || (! buf))
-               return -1;
+       if (! datum)
+               return 0;
 
-       switch (datum->type) {
-               case SDB_TYPE_INTEGER:
-                       ret = snprintf(buf, buflen, "%"PRIi64, datum->data.integer);
-                       break;
-               case SDB_TYPE_DECIMAL:
+       if (datum->type == SDB_TYPE_NULL) {
+               strncpy(buf, "NULL", buflen);
+               ret = 4;
+       }
+       else if (datum->type == SDB_TYPE_INTEGER) {
+               ret = snprintf(buf, buflen, "%"PRIi64, datum->data.integer);
+       }
+       else if (datum->type == SDB_TYPE_DECIMAL) {
+               if (isnan(datum->data.decimal))
+                       ret = snprintf(buf, buflen, "nan");
+               else
                        ret = snprintf(buf, buflen, "%g", datum->data.decimal);
-                       break;
-               case SDB_TYPE_STRING:
-                       if (! datum->data.string)
-                               data = "<NULL>";
-                       else {
-                               pos = 0;
-                               for (i = 0; i < strlen(datum->data.string); ++i) {
-                                       char byte = datum->data.string[i];
-
-                                       if ((byte == '\\') || (byte == '"')) {
-                                               tmp[pos] = '\\';
-                                               ++pos;
-                                       }
-                                       tmp[pos] = byte;
+       }
+       else if (datum->type == SDB_TYPE_STRING) {
+               if (! datum->data.string)
+                       is_null = 1;
+               else {
+                       pos = 0;
+                       for (i = 0; i < strlen(datum->data.string); ++i) {
+                               char byte = datum->data.string[i];
+
+                               if ((byte == '\\') || (byte == '"')) {
+                                       tmp[pos] = '\\';
                                        ++pos;
                                }
-                               tmp[pos] = '\0';
-                               data = tmp;
+                               tmp[pos] = byte;
+                               ++pos;
                        }
-                       break;
-               case SDB_TYPE_DATETIME:
-                       if (! sdb_strftime(tmp, sizeof(tmp), "%F %T %z",
-                                               datum->data.datetime))
-                               return -1;
-                       tmp[sizeof(tmp) - 1] = '\0';
+                       tmp[pos] = '\0';
                        data = tmp;
-                       break;
-               case SDB_TYPE_BINARY:
-                       pos = 0;
-                       for (i = 0; i < datum->data.binary.length; ++i) {
-                               int byte = (int)datum->data.binary.datum[i];
-                               char hex[] = {'0', '1', '2', '3', '4', '5', '6', '7',
-                                       '8', '9', 'a', 'b', 'c', 'd', 'e', 'f'};
+               }
+       }
+       else if (datum->type == SDB_TYPE_DATETIME) {
+               if (! sdb_strftime(tmp, sizeof(tmp), "%F %T %z",
+                                       datum->data.datetime))
+                       return -1;
+               tmp[sizeof(tmp) - 1] = '\0';
+               data = tmp;
+       }
+       else if (datum->type == SDB_TYPE_BINARY) {
+               pos = 0;
+               for (i = 0; i < datum->data.binary.length; ++i) {
+                       int byte = (int)datum->data.binary.datum[i];
+                       char hex[] = {'0', '1', '2', '3', '4', '5', '6', '7',
+                               '8', '9', 'a', 'b', 'c', 'd', 'e', 'f'};
 
-                               tmp[pos] = '\\';
-                               tmp[pos + 1] = 'x';
-                               pos += 2;
+                       tmp[pos] = '\\';
+                       tmp[pos + 1] = 'x';
+                       pos += 2;
 
-                               if (byte > 0xf) {
-                                       tmp[pos] = hex[byte >> 4];
-                                       ++pos;
-                               }
-                               tmp[pos] = hex[byte & 0xf];
+                       if (byte > 0xf) {
+                               tmp[pos] = hex[byte >> 4];
                                ++pos;
                        }
-                       if (datum->data.binary.datum) {
-                               tmp[pos] = '\0';
-                               data = tmp;
+                       tmp[pos] = hex[byte & 0xf];
+                       ++pos;
+               }
+               if (datum->data.binary.datum) {
+                       tmp[pos] = '\0';
+                       data = tmp;
+               }
+               else
+                       is_null = 1;
+       }
+       else if (datum->type == SDB_TYPE_REGEX) {
+               if (! datum->data.re.raw)
+                       is_null = 1;
+               else {
+                       snprintf(tmp, sizeof(tmp), "/%s/", datum->data.re.raw);
+                       data = tmp;
+               }
+       }
+       else if (datum->type & SDB_TYPE_ARRAY) {
+               ret = 1;
+               if (buflen > 0)
+                       buf[0] = '[';
+               for (i = 0; i < datum->data.array.length; ++i) {
+                       sdb_data_t v = SDB_DATA_INIT;
+                       size_t n;
+
+                       if (ret > 1) {
+                               if (buflen > ret + 1) {
+                                       buf[ret] = ',';
+                                       buf[ret + 1] = ' ';
+                               }
+                               ret += 2;
                        }
+
+                       sdb_data_array_get(datum, i, &v);
+                       if (buflen > ret)
+                               n = sdb_data_format(&v, buf + ret, buflen - ret, quoted);
                        else
-                               data = "<NULL>";
-                       break;
-               case SDB_TYPE_REGEX:
-                       if (! datum->data.re.raw)
-                               data = "<NULL>";
-                       else {
-                               snprintf(tmp, sizeof(tmp), "/%s/", datum->data.re.raw);
-                               data = tmp;
-                       }
-                       break;
+                               n = sdb_data_format(&v, NULL, 0, quoted);
+                       if (n > 0)
+                               ret += n;
+                       else
+                               break;
+               }
+               if (buflen > ret + 1) {
+                       buf[ret] = ']';
+                       buf[ret + 1] = '\0';
+               }
+               ++ret;
        }
 
-       if (data) {
+       if (is_null) {
+               /* never quote NULL */
+               strncpy(buf, "NULL", buflen);
+               ret = 4;
+       }
+       else if (data) {
                if (quoted == SDB_UNQUOTED)
                        ret = snprintf(buf, buflen, "%s", data);
                else if (quoted == SDB_SINGLE_QUOTED)
@@ -563,58 +1049,70 @@ sdb_data_format(const sdb_data_t *datum, char *buf, size_t buflen, int quoted)
                else
                        ret = snprintf(buf, buflen, "\"%s\"", data);
        }
-       buf[buflen - 1] = '\0';
+       if (buflen > 0)
+               buf[buflen - 1] = '\0';
        return ret;
 } /* sdb_data_format */
 
 int
-sdb_data_parse(char *str, int type, sdb_data_t *data)
+sdb_data_parse(const char *str, int type, sdb_data_t *data)
 {
        sdb_data_t tmp;
 
        char *endptr = NULL;
 
+       if (! str) {
+               errno = EINVAL;
+               return -1;
+       }
+
        errno = 0;
-       switch (type) {
-               case SDB_TYPE_INTEGER:
-                       tmp.data.integer = strtoll(str, &endptr, 0);
-                       break;
-               case SDB_TYPE_DECIMAL:
-                       tmp.data.decimal = strtod(str, &endptr);
-                       break;
-               case SDB_TYPE_STRING:
-                       tmp.data.string = str;
-                       break;
-               case SDB_TYPE_DATETIME:
-                       {
-                               double datetime = strtod(str, &endptr);
-                               tmp.data.datetime = DOUBLE_TO_SDB_TIME(datetime);
-                       }
-                       break;
-               case SDB_TYPE_BINARY:
-                       /* we don't support any binary information containing 0-bytes */
-                       tmp.data.binary.length = strlen(str);
-                       tmp.data.binary.datum = (unsigned char *)str;
-                       break;
-               case SDB_TYPE_REGEX:
-                       tmp.data.re.raw = strdup(str);
-                       if (! tmp.data.re.raw)
-                               return -1;
-                       if (regcomp(&tmp.data.re.regex, str,
-                                               REG_EXTENDED | REG_ICASE | REG_NOSUB)) {
-                               free(tmp.data.re.raw);
-                               sdb_log(SDB_LOG_ERR, "core: Failed to compile regular "
-                                               "expression '%s'", str);
-                               return -1;
-                       }
-                       if (! data) {
-                               tmp.type = SDB_TYPE_REGEX;
-                               sdb_data_free_datum(&tmp);
-                       }
-                       break;
-               default:
-                       errno = EINVAL;
+       if (type == SDB_TYPE_INTEGER) {
+               tmp.data.integer = strtoll(str, &endptr, 0);
+       }
+       else if (type == SDB_TYPE_DECIMAL) {
+               tmp.data.decimal = strtod(str, &endptr);
+       }
+       else if (type == SDB_TYPE_STRING) {
+               tmp.data.string = strdup(str);
+               if (! tmp.data.string)
+                       return -1;
+       }
+       else if (type == SDB_TYPE_DATETIME) {
+               double datetime = strtod(str, &endptr);
+               tmp.data.datetime = DOUBLE_TO_SDB_TIME(datetime);
+       }
+       else if (type == SDB_TYPE_BINARY) {
+               /* we don't support any binary information containing 0-bytes here */
+               tmp.data.binary.datum = (unsigned char *)strdup(str);
+               if (! tmp.data.binary.datum)
+                       return -1;
+               tmp.data.binary.length = strlen(str);
+       }
+       else if (type == SDB_TYPE_REGEX) {
+               tmp.data.re.raw = strdup(str);
+               if (! tmp.data.re.raw)
                        return -1;
+               if (regcomp(&tmp.data.re.regex, tmp.data.re.raw,
+                                       REG_EXTENDED | REG_ICASE | REG_NOSUB)) {
+                       sdb_log(SDB_LOG_ERR, "core: Failed to compile regular "
+                                       "expression '%s'", tmp.data.re.raw);
+                       free(tmp.data.re.raw);
+                       return -1;
+               }
+               if (! data) {
+                       tmp.type = SDB_TYPE_REGEX;
+                       sdb_data_free_datum(&tmp);
+               }
+       }
+       else if (type & SDB_TYPE_ARRAY) {
+               /* TODO */
+               errno = ENOTSUP;
+               return -1;
+       }
+       else {
+               errno = EINVAL;
+               return -1;
        }
 
        if ((type == SDB_TYPE_INTEGER) || (type == SDB_TYPE_DECIMAL)
@@ -639,5 +1137,24 @@ sdb_data_parse(char *str, int type, sdb_data_t *data)
        return 0;
 } /* sdb_data_parse */
 
+size_t
+sdb_data_sizeof(int type)
+{
+       sdb_data_t v;
+       if (type == SDB_TYPE_INTEGER)
+               return sizeof(v.data.integer);
+       else if (type == SDB_TYPE_DECIMAL)
+               return sizeof(v.data.decimal);
+       else if (type == SDB_TYPE_STRING)
+               return sizeof(v.data.string);
+       else if (type == SDB_TYPE_DATETIME)
+               return sizeof(v.data.datetime);
+       else if (type == SDB_TYPE_BINARY)
+               return sizeof(v.data.binary);
+       else if (type == SDB_TYPE_REGEX)
+               return sizeof(v.data.re);
+       return 0;
+} /* sdb_data_sizeof */
+
 /* vim: set tw=78 sw=4 ts=4 noexpandtab : */