wireshark/epan/ftypes/ftype-time.c

399 lines
8.8 KiB
C

/*
* Wireshark - Network traffic analyzer
* By Gerald Combs <gerald@wireshark.org>
* Copyright 2001 Gerald Combs
*
* SPDX-License-Identifier: GPL-2.0-or-later
*/
#include "config.h"
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
/*
* Just make sure we include the prototype for strptime as well
* (needed for glibc 2.2) but make sure we do this only if not
* yet defined.
*/
#ifndef __USE_XOPEN
# define __USE_XOPEN
#endif
#include <time.h>
#include <ftypes-int.h>
#include <epan/to_str.h>
#ifndef HAVE_STRPTIME
#include "wsutil/strptime.h"
#endif
static int
cmp_order(const fvalue_t *a, const fvalue_t *b)
{
return nstime_cmp(&(a->value.time), &(b->value.time));
}
/*
* Get a nanoseconds value, starting at "p".
*
* Returns true on success, false on failure.
*/
static gboolean
get_nsecs(const char *startp, int *nsecs)
{
int ndigits;
int scale;
const char *p;
int val;
int digit;
int i;
/*
* How many characters are in the string?
*/
ndigits = (int)strlen(startp);
/*
* If there are N characters in the string, the last of the
* characters would be the digit corresponding to 10^(9-N)
* nanoseconds.
*/
scale = 9 - ndigits;
/*
* Start at the last character, and work backwards.
*/
p = startp + ndigits;
val = 0;
while (p != startp) {
p--;
if (!g_ascii_isdigit(*p)) {
/*
* Not a digit - error.
*/
return FALSE;
}
digit = *p - '0';
if (digit != 0) {
/*
* Non-zero digit corresponding to that number
* of (10^scale) units.
*
* If scale is less than zero, this digit corresponds
* to a value less than a nanosecond, so this number
* isn't valid.
*/
if (scale < 0)
return FALSE;
for (i = 0; i < scale; i++)
digit *= 10;
val += digit;
}
scale++;
}
*nsecs = val;
return TRUE;
}
static gboolean
relative_val_from_unparsed(fvalue_t *fv, const char *s, gboolean allow_partial_value _U_, gchar **err_msg)
{
const char *curptr;
char *endptr;
gboolean negative = FALSE;
curptr = s;
if (*curptr == '-') {
negative = TRUE;
curptr++;
}
/*
* If it doesn't begin with ".", it should contain a seconds
* value.
*/
if (*curptr != '.') {
/*
* Get the seconds value.
*/
fv->value.time.secs = strtoul(curptr, &endptr, 10);
if (endptr == curptr || (*endptr != '\0' && *endptr != '.'))
goto fail;
curptr = endptr;
if (*curptr == '.')
curptr++; /* skip the decimal point */
} else {
/*
* No seconds value - it's 0.
*/
fv->value.time.secs = 0;
curptr++; /* skip the decimal point */
}
/*
* If there's more stuff left in the string, it should be the
* nanoseconds value.
*/
if (*curptr != '\0') {
/*
* Get the nanoseconds value.
*/
if (!get_nsecs(curptr, &fv->value.time.nsecs))
goto fail;
} else {
/*
* No nanoseconds value - it's 0.
*/
fv->value.time.nsecs = 0;
}
if (negative) {
fv->value.time.secs = -fv->value.time.secs;
fv->value.time.nsecs = -fv->value.time.nsecs;
}
return TRUE;
fail:
if (err_msg != NULL)
*err_msg = ws_strdup_printf("\"%s\" is not a valid time.", s);
return FALSE;
}
/* Returns TRUE if 's' starts with an abbreviated month name. */
static gboolean
parse_month_name(const char *s, int *tm_mon)
{
const char *months[] = {
"Jan", "Feb", "Mar", "Apr", "May", "Jun",
"Jul", "Aug", "Sep", "Oct", "Nov", "Dec"
};
for (int i = 0; i < 12; i++) {
if (g_ascii_strncasecmp(s, months[i], 3) == 0) {
*tm_mon = i;
return TRUE;
}
}
return FALSE;
}
/* Parses an absolute time value from a string. The string cannot have
* a time zone suffix and is always interpreted in local time.
*
* OS-dependent; e.g., on 32 bit versions of Windows when compiled to use
* _mktime32 treats dates before January 1, 1970 as invalid.
* (https://docs.microsoft.com/en-us/cpp/c-runtime-library/reference/mktime-mktime32-mktime64)
*/
static gboolean
absolute_val_from_string(fvalue_t *fv, const char *s, gchar **err_msg)
{
struct tm tm;
char *curptr = NULL;
gboolean has_seconds = TRUE;
memset(&tm, 0, sizeof(tm));
if (strlen(s) < sizeof("2000-1-1") - 1)
goto fail;
/* Do not use '%b' to parse the month name, it is locale-specific. */
if (s[3] == ' ' && parse_month_name(s, &tm.tm_mon))
curptr = strptime(s + 4, "%d, %Y %H:%M:%S", &tm);
if (curptr == NULL)
curptr = strptime(s,"%Y-%m-%dT%H:%M:%S", &tm);
if (curptr == NULL)
curptr = strptime(s,"%Y-%m-%d %H:%M:%S", &tm);
if (curptr == NULL) {
has_seconds = FALSE;
curptr = strptime(s,"%Y-%m-%d %H:%M", &tm);
}
if (curptr == NULL)
curptr = strptime(s,"%Y-%m-%d %H", &tm);
if (curptr == NULL)
curptr = strptime(s,"%Y-%m-%d", &tm);
if (curptr == NULL)
goto fail;
tm.tm_isdst = -1; /* let the computer figure out if it's DST */
fv->value.time.secs = mktime(&tm);
if (*curptr != '\0') {
/*
* Something came after the seconds field; it must be
* a nanoseconds field.
*/
if (*curptr != '.' || !has_seconds)
goto fail; /* it's not */
curptr++; /* skip the "." */
if (!g_ascii_isdigit((unsigned char)*curptr))
goto fail; /* not a digit, so not valid */
if (!get_nsecs(curptr, &fv->value.time.nsecs))
goto fail;
} else {
/*
* No nanoseconds value - it's 0.
*/
fv->value.time.nsecs = 0;
}
if (fv->value.time.secs == -1) {
/*
* XXX - should we supply an error message that mentions
* that the time specified might be syntactically valid
* but might not actually have occurred, e.g. a time in
* the non-existent time range after the clocks are
* set forward during daylight savings time (or possibly
* that it's in the time range after the clocks are set
* backward, so that there are two different times that
* it could be)?
*/
goto fail;
}
return TRUE;
fail:
if (err_msg != NULL)
*err_msg = ws_strdup_printf("\"%s\" is not a valid absolute time. Example: \"Nov 12, 1999 08:55:44.123\" or \"2011-07-04 12:34:56\"",
s);
return FALSE;
}
static gboolean
absolute_val_from_unparsed(fvalue_t *fv, const char *s, gboolean allow_partial_value _U_, gchar **err_msg)
{
return absolute_val_from_string(fv, s, err_msg);
}
static void
time_fvalue_new(fvalue_t *fv)
{
fv->value.time.secs = 0;
fv->value.time.nsecs = 0;
}
static void
time_fvalue_set(fvalue_t *fv, const nstime_t *value)
{
fv->value.time = *value;
}
static gpointer
value_get(fvalue_t *fv)
{
return &(fv->value.time);
}
static char *
absolute_val_to_repr(wmem_allocator_t *scope, const fvalue_t *fv, ftrepr_t rtype, int field_display)
{
gchar *rep;
char *buf;
switch (rtype) {
case FTREPR_DISPLAY:
rep = abs_time_to_str(scope, &fv->value.time,
(absolute_time_display_e)field_display, TRUE);
break;
case FTREPR_DFILTER:
/* absolute_val_from_string only accepts local time,
* with no time zone, so match that. */
rep = abs_time_to_str(scope, &fv->value.time,
ABSOLUTE_TIME_LOCAL, FALSE);
break;
default:
ws_assert_not_reached();
break;
}
if (rtype == FTREPR_DFILTER) {
buf = wmem_strdup_printf(scope, "\"%s\"", rep);
wmem_free(scope, rep);
}
else {
buf = rep;
}
return buf;
}
static char *
relative_val_to_repr(wmem_allocator_t *scope, const fvalue_t *fv, ftrepr_t rtype _U_, int field_display _U_)
{
return rel_time_to_secs_str(scope, &fv->value.time);
}
void
ftype_register_time(void)
{
static ftype_t abstime_type = {
FT_ABSOLUTE_TIME, /* ftype */
"FT_ABSOLUTE_TIME", /* name */
"Date and time", /* pretty_name */
0, /* wire_size */
time_fvalue_new, /* new_value */
NULL, /* free_value */
absolute_val_from_unparsed, /* val_from_unparsed */
absolute_val_from_string, /* val_from_string */
NULL, /* val_from_charconst */
absolute_val_to_repr, /* val_to_string_repr */
{ .set_value_time = time_fvalue_set }, /* union set_value */
{ .get_value_ptr = value_get }, /* union get_value */
cmp_order,
NULL, /* cmp_bitwise_and */
NULL, /* cmp_contains */
NULL, /* cmp_matches */
NULL,
NULL
};
static ftype_t reltime_type = {
FT_RELATIVE_TIME, /* ftype */
"FT_RELATIVE_TIME", /* name */
"Time offset", /* pretty_name */
0, /* wire_size */
time_fvalue_new, /* new_value */
NULL, /* free_value */
relative_val_from_unparsed, /* val_from_unparsed */
NULL, /* val_from_string */
NULL, /* val_from_charconst */
relative_val_to_repr, /* val_to_string_repr */
{ .set_value_time = time_fvalue_set }, /* union set_value */
{ .get_value_ptr = value_get }, /* union get_value */
cmp_order,
NULL, /* cmp_bitwise_and */
NULL, /* cmp_contains */
NULL, /* cmp_matches */
NULL,
NULL
};
ftype_register(FT_ABSOLUTE_TIME, &abstime_type);
ftype_register(FT_RELATIVE_TIME, &reltime_type);
}
/*
* Editor modelines - https://www.wireshark.org/tools/modelines.html
*
* Local variables:
* c-basic-offset: 8
* tab-width: 8
* indent-tabs-mode: t
* End:
*
* vi: set shiftwidth=8 tabstop=8 noexpandtab:
* :indentSize=8:tabSize=8:noTabs=false:
*/