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index 0b4b2e7419312e10d68f9725d7db061dea9d0d14..c8c7482e796f4438aeafdb8eebe4588223636e7b 100644 (file)
--- a/src/include/core/data.h
+++ b/src/include/core/data.h
/*
* SysDB - src/include/core/data.h
- * Copyright (C) 2012 Sebastian 'tokkee' Harl <sh@tokkee.org>
+ * Copyright (C) 2012-2014 Sebastian 'tokkee' Harl <sh@tokkee.org>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
#include <inttypes.h>
#include <stddef.h>
+#include <sys/types.h>
+#include <regex.h>
+
#ifdef __cplusplus
extern "C" {
#endif
enum {
- SDB_TYPE_INTEGER = 1,
+ SDB_TYPE_NULL = 0,
+ SDB_TYPE_INTEGER,
SDB_TYPE_DECIMAL,
SDB_TYPE_STRING,
SDB_TYPE_DATETIME,
SDB_TYPE_BINARY,
+ SDB_TYPE_REGEX, /* extended, case-insensitive POSIX regex */
};
#define SDB_TYPE_TO_STRING(t) \
- (((t) == SDB_TYPE_INTEGER) \
- ? "INTEGER" \
- : ((t) == SDB_TYPE_DECIMAL) \
- ? "DECIMAL" \
- : ((t) == SDB_TYPE_STRING) \
- ? "STRING" \
- : ((t) == SDB_TYPE_DATETIME) \
- ? "DATETIME" \
- : ((t) == SDB_TYPE_BINARY) \
- ? "BINARY" \
- : "UNKNOWN")
+ (((t) == SDB_TYPE_INTEGER) ? "INTEGER" \
+ : ((t) == SDB_TYPE_DECIMAL) ? "DECIMAL" \
+ : ((t) == SDB_TYPE_STRING) ? "STRING" \
+ : ((t) == SDB_TYPE_DATETIME) ? "DATETIME" \
+ : ((t) == SDB_TYPE_BINARY) ? "BINARY" \
+ : ((t) == SDB_TYPE_REGEX) ? "REGEX" : "UNKNOWN")
/*
* sdb_data_t:
size_t length;
unsigned char *datum;
} binary; /* SDB_TYPE_BINARY */
+ struct {
+ char *raw;
+ regex_t regex;
+ } re; /* SDB_TYPE_REGEX */
} data;
} sdb_data_t;
+#define SDB_DATA_INIT { SDB_TYPE_NULL, { .integer = 0 } }
+
+extern const sdb_data_t SDB_DATA_NULL;
/*
* sdb_data_copy:
* Copy the datum stored in 'src' to the memory location pointed to by 'dst'.
* Any dynamic data (strings, binary data) is copied to newly allocated
* memory. Use, for example, sdb_data_free_datum() to free any dynamic memory
- * stored in a datum.
+ * stored in a datum. On error, 'dst' is unchanged. Else, any dynamic memory
+ * in 'dst' will be freed.
*
* Returns:
* - 0 on success
void
sdb_data_free_datum(sdb_data_t *datum);
+/*
+ * sdb_data_cmp:
+ * Compare two data points. A NULL datum is considered less than any non-NULL
+ * datum. On data-type mismatch, the function always returns a non-zero value.
+ *
+ * Returns:
+ * - a value less than zero if d1 compares less than d2
+ * - zero if d1 compares equal to d2
+ * - a value greater than zero if d1 compares greater than d2
+ */
+int
+sdb_data_cmp(const sdb_data_t *d1, const sdb_data_t *d2);
+
+/*
+ * sdb_data_strcmp:
+ * Compare the string values of two data points. A NULL datum is considered
+ * less than any non-NULL. This function works for arbitrary combination of
+ * data-types.
+ *
+ * Returns:
+ * - a value less than zero if d1 compares less than d2
+ * - zero if d1 compares equal to d2
+ * - a value greater than zero if d1 compares greater than d2
+ */
+int
+sdb_data_strcmp(const sdb_data_t *d1, const sdb_data_t *d2);
+
+/*
+ * sdb_data_isnull:
+ * Determine whether a datum is NULL. A datum is considered to be NULL if
+ * either datum is NULL or if the type is SDB_TYPE_NULL or if the string or
+ * binary datum is NULL.
+ */
+_Bool
+sdb_data_isnull(const sdb_data_t *datum);
+
+/*
+ * Operators supported by sdb_data_eval_expr.
+ */
+enum {
+ SDB_DATA_ADD = 1, /* addition */
+ SDB_DATA_SUB, /* substraction */
+ SDB_DATA_MUL, /* multiplication */
+ SDB_DATA_DIV, /* division */
+ SDB_DATA_MOD, /* modulo */
+ SDB_DATA_CONCAT, /* string / binary data concatenation */
+};
+
+#define SDB_DATA_OP_TO_STRING(op) \
+ (((op) == SDB_DATA_ADD) ? "+" \
+ : ((op) == SDB_DATA_SUB) ? "-" \
+ : ((op) == SDB_DATA_MUL) ? "*" \
+ : ((op) == SDB_DATA_DIV) ? "/" \
+ : ((op) == SDB_DATA_MOD) ? "%" \
+ : ((op) == SDB_DATA_CONCAT) ? "||" : "UNKNOWN")
+
+/*
+ * sdb_data_parse_op:
+ * Parse the string representation of an operator supported by
+ * sdb_data_expr_eval.
+ *
+ * Returns:
+ * - the ID of the operator
+ * - a negative value in case the operator does not exist
+ */
+int
+sdb_data_parse_op(const char *op);
+
+/*
+ * sdb_data_expr_eval:
+ * Evaluate a simple arithmetic expression on two data points. String and
+ * binary data only support concatenation and all other data types only
+ * support the other operators. The result may be allocated dynamically and
+ * has to be freed by the caller (using sdb_data_free_datum).
+ *
+ * If any of the data points is a NULL value, the result is also NULL.
+ *
+ * The data-types of d1 and d2 have to be the same, except for the following
+ * cases:
+ * - <integer> or <decimal> <mul> <datetime>
+ * - <datetime> <mul> or <div> or <mod> <integer> or <decimal>
+ *
+ * Returns:
+ * - 0 on success
+ * - a negative value else
+ */
+int
+sdb_data_expr_eval(int op, const sdb_data_t *d1, const sdb_data_t *d2,
+ sdb_data_t *res);
+
/*
* sdb_data_strlen:
* Returns a (worst-case) estimate for the number of bytes required to format
* account.
*/
size_t
-sdb_data_strlen(sdb_data_t *datum);
+sdb_data_strlen(const sdb_data_t *datum);
enum {
SDB_UNQUOTED = 0,
* - a negative value else
*/
int
-sdb_data_format(sdb_data_t *datum, char *buf, size_t buflen, int quoted);
+sdb_data_format(const sdb_data_t *datum, char *buf, size_t buflen, int quoted);
+
+/*
+ * sdb_data_parse:
+ * Parse the specified string into a datum using the specified type. The
+ * string value is expected to be a raw value of the specified type. Integer
+ * and decimal numbers may be signed or unsigned octal (base 8, if the first
+ * character of the string is "0"), sedecimal (base 16, if the string includes
+ * the "0x" prefix), or decimal. Decimal numbers may also be "infinity" or
+ * "NaN" or may use a decimal exponent. Date-time values are expected to be
+ * specified as (floating point) number of seconds since the epoch. For string
+ * and binary data, the input string is passed to the datum. The function does
+ * not allocate new memory for that purpose. Use sdb_data_copy() if you want
+ * to do that. For regex data, the input string is copied to newly allocated
+ * memory and also compiled to a regex. Use sdb_data_free_datum() to free the
+ * dynamically allocated memory.
+ *
+ * The input string may be stored in 'data', that is, the function may be used
+ * to do an inline cast from a string to any other type. It is the callers
+ * responsibility to free the memory used by the string in case the target
+ * type does not keep a reference to it.
+ *
+ * Returns:
+ * - 0 on success
+ * - a negative value else
+ */
+int
+sdb_data_parse(char *str, int type, sdb_data_t *data);
+
+/*
+ * sdb_data_sizeof:
+ * Return the size of the data-type identified by the specified type.
+ *
+ * Returns:
+ * - the size of the data-type on success
+ * - 0 else
+ */
+size_t
+sdb_data_sizeof(int type);
#ifdef __cplusplus
} /* extern "C" */