Added an initial implementation of parsedate(), parsedate_etc(), get_dateformats(),

and set_dateformats().
It's not complete yet, but already quite useful.
Added a "d.m.y" to the R5 set of formats.


git-svn-id: file:///srv/svn/repos/haiku/trunk/current@4367 a95241bf-73f2-0310-859d-f6bbb57e9c96
This commit is contained in:
Axel Dörfler
2003-08-23 18:32:09 +00:00
parent 6f82bba82a
commit cb19965e13
+733
View File
@@ -0,0 +1,733 @@
/*
** Copyright 2003, Axel Dörfler, [email protected]. All rights reserved.
** Distributed under the terms of the OpenBeOS License.
*/
#include <OS.h>
#include <parsedate.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <ctype.h>
/* The date format is as follows:
*
* a/A weekday
* d day of month
* b/B month name
* m month
* y/Y year
* H/I hours
* M minute
* S seconds
* p meridian (i.e. am/pm)
* T time unit: last hour, next tuesday, today, ...
* z/Z time zone
* - dash or slash
*
* Any of ",.:" is allowed and will be expected in the input string as is.
* You can enclose a single field with "[]" to mark it as being optional.
* A space stands for white space.
* No other character is allowed.
*/
static const char * const kFormatsTable[] = {
"[A][,] B d[,] H:M:S [p] Y[,] [Z]",
"[A][,] B d[,] [Y][,] H:M:S [p] [Z]",
"[A][,] B d[,] [Y][,] H:M [p][,] [Z]",
"[A][,] B d[,] [Y][,] H [p][,] [Z]",
"[A][,] B d[,] H:M [p][,] [Y] [Z]",
"[A][,] d B[,] [Y][,] H:M [p][,] [Z]",
"[A][,] d B[,] [Y][,] H:M:S [p][,] [Z]",
"[A][,] d B[,] H:M:S [Y][,] [p][,] [Z]",
"[A][,] d B[,] H:M [Y][,] [p][,] [Z]",
"d.m.y H:M:S [p] [Z]",
"d.m.y H:M [p] [Z]",
"d.m.y",
"[A][,] m-d-y[,] [H][:][M] [p]",
"[A][,] m-d[,] H:M [p]",
"[A][,] m-d[,] H[p]",
"[A][,] m-d",
"[A][,] B d[,] Y",
"[A][,] H:M [p]",
"[A][,] H [p]",
"H:M [p][,] [A]",
"H [p][,] [A]",
"[A][,] B d[,] H:M:S [p] [Z] [Y]",
"[A][,] B d[,] H:M [p] [Z] [Y]",
"[A][,] d B [,] H:M:S [p] [Z] [Y]",
"[A][,] d B [,] H:M [p] [Z] [Y]",
"[A][,] d-B-Y H:M:S [p] [Z]",
"[A][,] d-B-Y H:M [p] [Z]",
"d B Y H:M:S [Z]",
"d B Y H:M [Z]",
"y-m-d",
"y-m-d H:M:S [p] [Z]",
"m-d-y H[p]",
"m-d-y H:M[p]",
"m-d-y H:M:S[p]",
"H[p] m-d-y",
"H:M[p] m-d-y",
"H:M:S[p] m-d-y",
"A[,] H:M:S [p] [Z]",
"A[,] H:M [p] [Z]",
"H:M:S [p] [Z]",
"H:M [p] [Z]",
"A[,] [B] [d] [Y]",
"A[,] [d] [B] [Y]",
"B d[,][Y] H[p][,] [Z]",
"B d[,] H[p]",
"B d [,] H:M [p]",
"d B [,][Y] H [p] [Z]",
"d B [,] H:M [p]",
"B d [,][Y]",
"B d [,] H:M [p][,] [Y]",
"B d [,] H [p][,] [Y]",
"d B [,][Y]",
"H[p] [,] B d",
"H:M[p] [,] B d",
"T [T][T][T][T][T]",
"T H:M:S [p]",
"T H:M [p]",
"T H [p]",
"H:M [p] T",
"H [p] T",
"H [p]",
NULL
};
static const char * const *sFormatsTable = kFormatsTable;
enum field_type {
TYPE_DAY_UNIT = 0x0100,
TYPE_SECOND_UNIT = 0x0200,
TYPE_MONTH_UNIT = 0x0400,
TYPE_YEAR_UNIT = 0x0800,
TYPE_RELATIVE = 0x1000,
TYPE_NOT_MODIFIABLE = 0x2000,
TYPE_MODIFIER = 0x4000,
TYPE_UNIT = 0x8000,
TYPE_UNIT_MASK = 0x0f00,
TYPE_MASK = 0x00ff,
TYPE_UNKNOWN = 0,
TYPE_DAY = 1 | TYPE_DAY_UNIT,
TYPE_MONTH = 2 | TYPE_MONTH_UNIT,
TYPE_YEAR = 3 | TYPE_MONTH_UNIT,
TYPE_WEEKDAY = 4 | TYPE_DAY_UNIT,
TYPE_NOW = 5,
TYPE_HOUR = 6 | TYPE_SECOND_UNIT,
TYPE_MINUTE = 7 | TYPE_SECOND_UNIT,
TYPE_SECOND = 8 | TYPE_SECOND_UNIT,
TYPE_TIME_ZONE = 9 | TYPE_SECOND_UNIT,
TYPE_MERIDIAN = 10 | TYPE_SECOND_UNIT,
TYPE_DASH = 12,
TYPE_DOT = 13,
TYPE_COLON = 14,
TYPE_SEMICOLON = 15,
TYPE_PLUS_MINUS = 16 | TYPE_MODIFIER | TYPE_RELATIVE,
TYPE_NEXT_LAST_THIS = 17 | TYPE_MODIFIER | TYPE_RELATIVE,
TYPE_END,
};
enum value_type {
VALUE_NUMERICAL,
VALUE_STRING,
VALUE_CHAR,
};
enum value_modifier {
MODIFY_PLUS,
MODIFY_MINUS,
MODIFY_NEXT,
MODIFY_THIS,
MODIFY_LAST,
};
struct known_identifier {
const char *string;
int32 type;
int32 value;
};
static const known_identifier kIdentifiers[] = {
{"today", TYPE_RELATIVE | TYPE_NOT_MODIFIABLE | TYPE_DAY_UNIT, 0},
{"tomorrow", TYPE_RELATIVE | TYPE_NOT_MODIFIABLE | TYPE_DAY_UNIT, 1},
{"yesterday", TYPE_RELATIVE | TYPE_NOT_MODIFIABLE | TYPE_DAY_UNIT, -1},
{"now", TYPE_RELATIVE | TYPE_NOT_MODIFIABLE | TYPE_NOW, 0},
{"this", TYPE_NEXT_LAST_THIS, 0},
{"next", TYPE_NEXT_LAST_THIS, 1},
{"last", TYPE_NEXT_LAST_THIS, -1},
{"year", TYPE_UNIT | TYPE_RELATIVE | TYPE_YEAR_UNIT, 1},
{"month", TYPE_UNIT | TYPE_RELATIVE | TYPE_MONTH_UNIT, 1},
{"day", TYPE_UNIT | TYPE_RELATIVE | TYPE_DAY_UNIT, 1},
{"days", TYPE_UNIT | TYPE_RELATIVE | TYPE_DAY_UNIT, 1},
{"hour", TYPE_UNIT | TYPE_RELATIVE | TYPE_SECOND_UNIT, 1 * 60 * 60},
{"hrs", TYPE_UNIT | TYPE_RELATIVE | TYPE_SECOND_UNIT, 1 * 60 * 60},
{"hours", TYPE_UNIT | TYPE_RELATIVE | TYPE_SECOND_UNIT, 1 * 60 * 60},
{"sec", TYPE_UNIT | TYPE_RELATIVE | TYPE_SECOND_UNIT, 1},
{"second", TYPE_UNIT | TYPE_RELATIVE | TYPE_SECOND_UNIT, 1},
{"seconds", TYPE_UNIT | TYPE_RELATIVE | TYPE_SECOND_UNIT, 1},
{"min", TYPE_UNIT | TYPE_RELATIVE | TYPE_SECOND_UNIT, 60},
{"minute", TYPE_UNIT | TYPE_RELATIVE | TYPE_SECOND_UNIT, 60},
{"minutes", TYPE_UNIT | TYPE_RELATIVE | TYPE_SECOND_UNIT, 60},
{"am", TYPE_MERIDIAN | TYPE_NOT_MODIFIABLE, 0},
{"pm", TYPE_MERIDIAN | TYPE_NOT_MODIFIABLE, 12 * 60 * 60}, // 12 hours
{"sunday", TYPE_WEEKDAY, 0},
{"monday", TYPE_WEEKDAY, 1},
{"tuesday", TYPE_WEEKDAY, 2},
{"wednesday", TYPE_WEEKDAY, 3},
{"thursday", TYPE_WEEKDAY, 4},
{"friday", TYPE_WEEKDAY, 5},
{"saturday", TYPE_WEEKDAY, 6},
{"january", TYPE_MONTH, 1},
{"february", TYPE_MONTH, 2},
{"march", TYPE_MONTH, 3},
{"april", TYPE_MONTH, 4},
{"may", TYPE_MONTH, 5},
{"june", TYPE_MONTH, 6},
{"july", TYPE_MONTH, 7},
{"august", TYPE_MONTH, 8},
{"september", TYPE_MONTH, 9},
{"october", TYPE_MONTH, 10},
{"november", TYPE_MONTH, 11},
{"december", TYPE_MONTH, 12},
{"GMT", TYPE_TIME_ZONE, 0},
// ToDo: add more time zones
{NULL, TYPE_UNKNOWN, 0},
};
#define MAX_ELEMENTS 32
struct parsed_element {
int32 type;
int32 value_type;
int32 modifier;
bigtime_t value;
};
bool
isType(int32 typeA, int32 typeB)
{
return (typeA & TYPE_MASK) == (typeB & TYPE_MASK);
}
status_t
preparseDate(const char *dateString, parsed_element *elements)
{
int32 index = 0;
char c;
if (dateString == NULL)
return B_ERROR;
for (; (c = dateString[0]) != '\0'; dateString++) {
// we don't care about spaces
if (isspace(c))
continue;
// if we're reached our maximum number of elements, bail out
if (index >= MAX_ELEMENTS)
return B_ERROR;
memset(&elements[index], 0, sizeof(parsed_element));
if (c == ',') {
elements[index].type = TYPE_COLON;
elements[index].value_type = VALUE_CHAR;
} else if (c == '.') {
elements[index].type = TYPE_DOT;
elements[index].value_type = VALUE_CHAR;
} else if (c == '/' || c == '-') {
// ToDo: "-" can also be the minus modifier... - how to distinguish?
elements[index].type = TYPE_DASH;
elements[index].value_type = VALUE_CHAR;
} else if (c == ':') {
elements[index].type = TYPE_SEMICOLON;
elements[index].value_type = VALUE_CHAR;
} else if (c == '+') {
elements[index].type = TYPE_RELATIVE;
elements[index].value_type = VALUE_CHAR;
elements[index].modifier = MODIFY_PLUS;
// this counts for the next element
continue;
} else if (c == '-') {
// ToDo: this never happens, due to TYPE_DASH
elements[index].type = TYPE_MODIFIER;
elements[index].value_type = VALUE_CHAR;
elements[index].modifier = MODIFY_MINUS;
// this counts for the next element
continue;
} else if (isdigit(c)) {
// fetch whole number
elements[index].type = TYPE_UNKNOWN;
elements[index].value_type = VALUE_NUMERICAL;
elements[index].value = atoll(dateString);
// skip number
while (isdigit(dateString[1]))
dateString++;
} else if (isalpha(c)) {
// fetch whole string
const char *string = dateString;
while (isalpha(dateString[1]))
dateString++;
int32 length = dateString + 1 - string;
// compare with known strings
// ToDo: should understand other languages as well...
const known_identifier *identifier = kIdentifiers;
for (; identifier->string; identifier++) {
if (!strncasecmp(identifier->string, string, length)
&& !identifier->string[length])
break;
}
if (identifier->string == NULL) {
// unknown string, we don't have to parse any further
return B_ERROR;
}
if (index > 0 && (identifier->type & TYPE_UNIT) != 0) {
// this is just a unit, so it will give the last value a meaning
if (elements[--index].value_type != VALUE_NUMERICAL
&& elements[index].type != TYPE_NEXT_LAST_THIS)
return B_ERROR;
elements[index].value *= identifier->value;
} else if (index > 0 && elements[index - 1].type == TYPE_NEXT_LAST_THIS) {
if (isType(identifier->type, TYPE_MONTH)
|| isType(identifier->type, TYPE_WEEKDAY)) {
index--;
switch (elements[index].value) {
case -1:
elements[index].modifier = MODIFY_LAST;
break;
case 0:
elements[index].modifier = MODIFY_THIS;
break;
case 1:
elements[index].modifier = MODIFY_NEXT;
break;
}
elements[index].value = identifier->value;
} else
return B_ERROR;
} else {
elements[index].value_type = VALUE_STRING;
elements[index].value = identifier->value;
}
elements[index].type = identifier->type;
}
// see if we can join any preceding modifiers
if (index > 0
&& (elements[index - 1].type & TYPE_MODIFIER) != 0
&& (elements[index].type & TYPE_NOT_MODIFIABLE) == 0) {
// copy the current one to the last and go on
elements[index].modifier = elements[index - 1].modifier;
elements[index].value *= elements[index - 1].value;
elements[index - 1] = elements[index];
} else {
// we filled out one parsed_element
index++;
}
}
// were there any elements?
if (index == 0)
return B_ERROR;
elements[index].type = TYPE_END;
return B_OK;
}
static void
computeRelativeUnit(parsed_element &element, struct tm &tm, time_t &now, bool &makeTime, bool isString)
{
uint32 type = element.type;
// ToDo: should change flags as well!
makeTime = true;
localtime_r(&now, &tm);
// set the relative start depending on unit
if (type & (TYPE_DAY_UNIT | TYPE_MONTH_UNIT | TYPE_YEAR_UNIT)) {
tm.tm_hour = 0;
tm.tm_min = 0;
tm.tm_sec = 0;
}
if (type & (TYPE_MONTH_UNIT | TYPE_YEAR_UNIT))
tm.tm_mday = 1;
if (type & TYPE_YEAR_UNIT)
tm.tm_mon = 0;
// adjust value
if (type & TYPE_RELATIVE) {
if (type & TYPE_MONTH_UNIT)
tm.tm_mon += element.value;
else if (type & TYPE_DAY_UNIT)
tm.tm_mday += element.value;
else if (type & TYPE_SECOND_UNIT)
tm.tm_sec += element.value;
else if (!isType(type, TYPE_NOW))
;
//puts("what's going on here?");
} else if (isType(type, TYPE_WEEKDAY)) {
tm.tm_mday += abs(element.value) - tm.tm_wday;
if (element.modifier == MODIFY_NEXT)
tm.tm_mday += 7;
else if (element.modifier == MODIFY_LAST)
tm.tm_mday -= 7;
}
}
static time_t
computeDate(const char *format, bool *optional, parsed_element *elements, time_t now, int *_flags)
{
//printf("matches: %s\n", format);
parsed_element *element = elements;
uint32 position = 0;
struct tm tm;
time_t date;
bool relative = false, makeTime = false;
// ToDo: only call time() if necessary
if (now == -1)
now = time(NULL);
memset(&tm, 0, sizeof(tm));
// localtime_r(&now, &tm);
// printf("now = %ld, -> %ld\n", now, mktime(&tm));
while (element->type != TYPE_END) {
// skip whitespace
while (isspace(format[0]))
format++;
if (format[0] == '[' && format[2] == ']') {
// does this optional parameter not match our date string?
if (!optional[position]) {
format += 3;
position++;
continue;
}
format++;
}
switch (element->value_type) {
case VALUE_CHAR:
// skip the single character
break;
case VALUE_NUMERICAL:
switch (format[0]) {
case 'd':
tm.tm_mday = element->value;
makeTime = true;
break;
case 'm':
tm.tm_mon = element->value - 1;
makeTime = true;
break;
case 'H':
case 'I':
tm.tm_hour = element->value;
makeTime = true;
break;
case 'M':
tm.tm_min = element->value;
makeTime = true;
break;
case 'S':
tm.tm_sec = element->value;
makeTime = true;
break;
case 'y':
case 'Y':
tm.tm_year = element->value;
if (tm.tm_year > 1900)
tm.tm_year -= 1900;
makeTime = true;
break;
case 'T':
// ToDo:!
computeRelativeUnit(*element, tm, now, makeTime, false);
break;
}
break;
case VALUE_STRING:
switch (format[0]) {
case 'a': // weekday
case 'A':
break;
case 'b':
case 'B':
break;
case 'p':
break;
case 'z': // time zone
case 'Z':
break;
case 'T':
computeRelativeUnit(*element, tm, now, makeTime, true);
break;
}
break;
}
// format matched at this point, check next element
format++;
position++;
element++;
}
if (makeTime)
return mktime(&tm);
return now;
}
time_t
parsedate_etc(const char *dateString, time_t now, int *_flags)
{
// preparse date string so that it can be easily compared to our formats
parsed_element elements[MAX_ELEMENTS];
if (preparseDate(dateString, elements) < B_OK) {
*_flags = PARSEDATE_INVALID_DATE;
return B_ERROR;
}
/*for (int32 index = 0; elements[index].type != TYPE_END; index++) {
parsed_element e = elements[index];
char type[32];
sprintf(type, "0x%lx", e.type);
if (e.type & TYPE_UNIT)
strcat(type, " unit");
if (e.type & TYPE_RELATIVE)
strcat(type, " relative");
printf(" %ld: type = %ld (%s), value = %Ld (%s)\n",
index, e.type & TYPE_MASK, type, e.value,
e.value_type == VALUE_NUMERICAL ? "numerical" :
(e.value_type == VALUE_STRING ? "string" : "char"));
}*/
bool optional[MAX_ELEMENTS];
for (int32 index = 0; sFormatsTable[index]; index++) {
// test if this format matches our date string
const char *format = sFormatsTable[index];
uint32 position = 0;
parsed_element *element = elements;
while (element->type != TYPE_END) {
// skip whitespace
while (isspace(format[0]))
format++;
if (format[0] == '[' && format[2] == ']') {
optional[position] = true;
format++;
} else
optional[position] = false;
switch (element->value_type) {
case VALUE_CHAR:
// check the allowed single characters
switch (element->type & TYPE_MASK) {
case TYPE_DOT:
if (format[0] != '.')
goto next_format;
break;
case TYPE_DASH:
if (format[0] != '/' && format[0] != '-')
goto next_format;
break;
case TYPE_COLON:
if (format[0] != ',')
goto next_format;
break;
case TYPE_SEMICOLON:
if (format[0] != ';')
goto next_format;
break;
default:
goto next_format;
}
break;
case VALUE_NUMERICAL:
switch (format[0]) {
case 'd':
if (element->value > 31)
goto next_format;
break;
case 'm':
if (element->value > 12)
goto next_format;
break;
case 'H':
case 'I':
if (element->value > 24)
goto next_format;
break;
case 'M':
case 'S':
if (element->value > 59)
goto next_format;
break;
case 'y':
case 'Y':
case 'T':
break;
default:
goto next_format;
}
break;
case VALUE_STRING:
switch (format[0]) {
case 'a': // weekday
case 'A':
if ((element->type & TYPE_MASK) != TYPE_WEEKDAY)
goto next_format;
break;
case 'b': // month
case 'B':
if ((element->type & TYPE_MASK) != TYPE_MONTH)
goto next_format;
break;
case 'p': // meridian
if ((element->type & TYPE_MASK) != TYPE_MERIDIAN)
goto next_format;
break;
case 'z': // time zone
case 'Z':
if ((element->type & TYPE_MASK) != TYPE_TIME_ZONE)
goto next_format;
break;
case 'T':
// last/next/this
break;
default:
goto next_format;
}
break;
}
// format matched at this point, check next element
if (optional[position])
format++;
format++;
position++;
element++;
continue;
next_format:
// format didn't match element - let's see if the current
// one is only optional (in which case we can continue)
if (!optional[position])
goto skip_format;
optional[position] = false;
format += 2;
position++;
// skip the closing ']'
}
// check if the format is already empty (since we reached our last element)
while (format[0]) {
if (format[0] == '[')
format += 3;
else if (isspace(format[0]))
format++;
else
break;
}
if (format[0])
goto skip_format;
// made it here? then we seem to have found our guy
return computeDate(sFormatsTable[index], optional, elements, now, _flags);
skip_format:
// check if the next format has the same beginning as the skipped one,
// and if so, skip that one, too.
int32 length = format + 1 - sFormatsTable[index];
while (sFormatsTable[index + 1]
&& !strncmp(sFormatsTable[index], sFormatsTable[index + 1], length))
index++;
}
// didn't find any matching formats
return B_ERROR;
}
time_t
parsedate(const char *dateString, time_t now)
{
int flags = 0;
return parsedate_etc(dateString, now, &flags);
}
void
set_dateformats(const char **table)
{
sFormatsTable = table ? table : kFormatsTable;
}
const char **
get_dateformats(void)
{
return const_cast<const char **>(sFormatsTable);
}