X-Git-Url: https://git.tokkee.org/?p=sysdb.git;a=blobdiff_plain;f=src%2Finclude%2Fcore%2Fdata.h;h=e529fb9ceec24749aca3efdf8841bbc2dd073e23;hp=58e92cde59583dd7b114b163304223ecdb2f5d9c;hb=42f08911b5ba35dbd0e3dadc0f3785f8fa3a946a;hpb=4f8a84025ecb0d230407d54743186c2b4d1941c9 diff --git a/src/include/core/data.h b/src/include/core/data.h index 58e92cd..e529fb9 100644 --- a/src/include/core/data.h +++ b/src/include/core/data.h @@ -1,6 +1,6 @@ /* * SysDB - src/include/core/data.h - * Copyright (C) 2012 Sebastian 'tokkee' Harl + * Copyright (C) 2012-2014 Sebastian 'tokkee' Harl * All rights reserved. * * Redistribution and use in source and binary forms, with or without @@ -29,47 +29,89 @@ #define SDB_CORE_DATA_H 1 #include "core/time.h" -#include "utils/strbuf.h" #include +#include #include +#include +#include + #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 */ + + /* flags: */ + SDB_TYPE_ARRAY = 1 << 8, +}; + +#define SDB_TYPE_TO_STRING(t) \ + (((t) == SDB_TYPE_NULL) ? "NULL" \ + : ((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" \ + : ((t) == (SDB_TYPE_ARRAY | SDB_TYPE_INTEGER)) ? "[]INTEGER" \ + : ((t) == (SDB_TYPE_ARRAY | SDB_TYPE_DECIMAL)) ? "[]DECIMAL" \ + : ((t) == (SDB_TYPE_ARRAY | SDB_TYPE_STRING)) ? "[]STRING" \ + : ((t) == (SDB_TYPE_ARRAY | SDB_TYPE_DATETIME)) ? "[]DATETIME" \ + : ((t) == (SDB_TYPE_ARRAY | SDB_TYPE_BINARY)) ? "[]BINARY" \ + : ((t) == (SDB_TYPE_ARRAY | SDB_TYPE_REGEX)) ? "[]REGEX" \ + : "UNKNOWN") + +union sdb_datum; +typedef union sdb_datum sdb_datum_t; + +union sdb_datum { + int64_t integer; /* SDB_TYPE_INTEGER */ + double decimal; /* SDB_TYPE_DECIMAL */ + char *string; /* SDB_TYPE_STRING */ + sdb_time_t datetime; /* SDB_TYPE_DATETIME */ + struct { + size_t length; + unsigned char *datum; + } binary; /* SDB_TYPE_BINARY */ + struct { + char *raw; + regex_t regex; + } re; /* SDB_TYPE_REGEX */ + + struct { + size_t length; + void *values; + } array; }; /* * sdb_data_t: - * A datum retrieved from an arbitrary data source. + * An arbitrary value of a specified type. */ typedef struct { - int type; - union { - int64_t integer; /* SDB_TYPE_INTEGER */ - double decimal; /* SDB_TYPE_DECIMAL */ - char *string; /* SDB_TYPE_STRING */ - sdb_time_t datetime; /* SDB_TYPE_DATETIME */ - struct { - size_t length; - unsigned char *datum; - } binary; /* SDB_TYPE_BINARY */ - } data; + int type; /* type of the datum */ + sdb_datum_t 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 @@ -81,24 +123,206 @@ sdb_data_copy(sdb_data_t *dst, const sdb_data_t *src); /* * sdb_data_free_datum: * Free any dynamic memory referenced by the specified datum. Does not free - * the memory allocated for the sdb_data_t object itself. This function must + * the memory allocated by the sdb_data_t object itself. This function must * not be used if any static or stack memory is referenced from the data * object. */ 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); + +/* + * sdb_data_inarray: + * Determine whether a datum is included in an array based on the usual + * comparison function of the value's type. The element type of the array has + * to match the type of the value. The value may be another array. In that + * case, the element types have to match and the function returns true if all + * elements of the first array are included in the second where order does not + * matter. + */ +bool +sdb_data_inarray(const sdb_data_t *value, const sdb_data_t *array); + +/* + * sdb_data_array_get: + * Get the i-th value stored in the specified array and store an alias in + * 'value'. Storing an alias means that the value points to the actual array + * element. Do *not* free the value after using it (i.e., don't use + * sdb_data_free_datum). + * + * Returns: + * - 0 on success + * - a negative value else + */ +int +sdb_data_array_get(const sdb_data_t *array, size_t i, sdb_data_t *value); + +/* + * 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: + * - or + * - or
or or + * + * 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_expr_type: + * Determine the type of the expression when applying the specified operator + * to the specified types. Note that if an actual value is a typed NULL value + * (e.g. a NULL string value), the return value of this function does not + * match the return type of sdb_data_expr_eval. + * + * See the documentation of sdb_data_expr_eval() for a description of which + * operations are supported. + * + * Returns: + * - the type id on success + * - a negative value else + */ +int +sdb_data_expr_type(int op, int type1, int type2); + +/* + * sdb_data_strlen: + * Returns a (worst-case) estimate for the number of bytes required to format + * the datum as a string. Does not take the terminating null byte into + * account. + */ +size_t +sdb_data_strlen(const sdb_data_t *datum); + +enum { + SDB_UNQUOTED = 0, + SDB_SINGLE_QUOTED, + SDB_DOUBLE_QUOTED, +}; + /* * sdb_data_format: - * Append the specified datum to the specified string buffer using a default - * format. + * Output the specified datum to the specified string using a default format. + * The value of 'quoted' determines whether and how non-integer and + * non-decimal values are quoted. If the buffer size is less than the return + * value of sdb_data_strlen, the datum may be truncated. The buffer will + * always be nul-terminated after calling this function. + * + * Returns: + * - the number of characters written to the buffer (excluding the terminated + * null byte) or the number of characters which would have been written in + * case the output was truncated + */ +size_t +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. New memory + * will be allocated as necessary and will have to be free'd using + * sdb_data_free_datum(). * * Returns: * - 0 on success * - a negative value else */ int -sdb_data_format(sdb_data_t *datum, sdb_strbuf_t *buf); +sdb_data_parse(const 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" */