nexmon – Rev 1
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/* value_string.c
* Routines for value_strings
*
* Wireshark - Network traffic analyzer
* By Gerald Combs <gerald@wireshark.org>
* Copyright 1998 Gerald Combs
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
#include "config.h"
#include <stdio.h>
#include <string.h>
#include "wmem/wmem.h"
#include "proto.h"
#include "to_str.h"
#include "value_string.h"
/* REGULAR VALUE STRING */
/* Tries to match val against each element in the value_string array vs.
Returns the associated string ptr on a match.
Formats val with fmt, and returns the resulting string, on failure. */
const gchar *
val_to_str(const guint32 val, const value_string *vs, const char *fmt)
{
const gchar *ret;
DISSECTOR_ASSERT(fmt != NULL);
ret = try_val_to_str(val, vs);
if (ret != NULL)
return ret;
return wmem_strdup_printf(wmem_packet_scope(), fmt, val);
}
gchar *
val_to_str_wmem(wmem_allocator_t *scope, const guint32 val, const value_string *vs, const char *fmt)
{
const gchar *ret;
DISSECTOR_ASSERT(fmt != NULL);
ret = try_val_to_str(val, vs);
if (ret != NULL)
return wmem_strdup(scope, ret);
return wmem_strdup_printf(scope, fmt, val);
}
/* Tries to match val against each element in the value_string array vs.
Returns the associated string ptr on a match.
Returns 'unknown_str', on failure. */
const gchar *
val_to_str_const(const guint32 val, const value_string *vs,
const char *unknown_str)
{
const gchar *ret;
DISSECTOR_ASSERT(unknown_str != NULL);
ret = try_val_to_str(val, vs);
if (ret != NULL)
return ret;
return unknown_str;
}
/* Tries to match val against each element in the value_string array vs.
Returns the associated string ptr, and sets "*idx" to the index in
that table, on a match, and returns NULL, and sets "*idx" to -1,
on failure. */
const gchar *
try_val_to_str_idx(const guint32 val, const value_string *vs, gint *idx)
{
gint i = 0;
DISSECTOR_ASSERT(idx != NULL);
if(vs) {
while (vs[i].strptr) {
if (vs[i].value == val) {
*idx = i;
return(vs[i].strptr);
}
i++;
}
}
*idx = -1;
return NULL;
}
/* Like try_val_to_str_idx(), but doesn't return the index. */
const gchar *
try_val_to_str(const guint32 val, const value_string *vs)
{
gint ignore_me;
return try_val_to_str_idx(val, vs, &ignore_me);
}
/* 64-BIT VALUE STRING */
const gchar *
val64_to_str(const guint64 val, const val64_string *vs, const char *fmt)
{
const gchar *ret;
DISSECTOR_ASSERT(fmt != NULL);
ret = try_val64_to_str(val, vs);
if (ret != NULL)
return ret;
return wmem_strdup_printf(wmem_packet_scope(), fmt, val);
}
const gchar *
val64_to_str_const(const guint64 val, const val64_string *vs,
const char *unknown_str)
{
const gchar *ret;
DISSECTOR_ASSERT(unknown_str != NULL);
ret = try_val64_to_str(val, vs);
if (ret != NULL)
return ret;
return unknown_str;
}
const gchar *
try_val64_to_str_idx(const guint64 val, const val64_string *vs, gint *idx)
{
gint i = 0;
DISSECTOR_ASSERT(idx != NULL);
if(vs) {
while (vs[i].strptr) {
if (vs[i].value == val) {
*idx = i;
return(vs[i].strptr);
}
i++;
}
}
*idx = -1;
return NULL;
}
const gchar *
try_val64_to_str(const guint64 val, const val64_string *vs)
{
gint ignore_me;
return try_val64_to_str_idx(val, vs, &ignore_me);
}
/* REVERSE VALUE STRING */
/* We use the same struct as for regular value strings, but we look up strings
* and return values instead */
/* Like val_to_str except backwards */
guint32
str_to_val(const gchar *val, const value_string *vs, const guint32 err_val)
{
gint i;
i = str_to_val_idx(val, vs);
if (i >= 0) {
return vs[i].value;
}
return err_val;
}
/* Find the index of a string in a value_string, or -1 when not present */
gint
str_to_val_idx(const gchar *val, const value_string *vs)
{
gint i = 0;
if(vs) {
while (vs[i].strptr) {
if (strcmp(vs[i].strptr, val) == 0) {
return i;
}
i++;
}
}
return -1;
}
/* EXTENDED VALUE STRING */
/* Extended value strings allow fast(er) value_string array lookups by
* using (if possible) direct access or a binary search of the array.
*
* If the values in the value_string array are a contiguous range of values
* from min to max, the value will be used as as a direct index into the array.
*
* If the values in the array are not contiguous (ie: there are "gaps"),
* but are in assending order a binary search will be used.
*
* If direct access or binary search cannot be used, then a linear search
* is used and a warning is emitted.
*
* Note that the value_string array used with VALUE_STRING_EXT_INIT
* *must* be terminated with {0, NULL}).
*
* Extended value strings are defined at compile time as follows:
* static const value_string vs[] = { {value1, "string1"},
* {value2, "string2"},
* ...,
* {0, NULL}};
* static value_string_ext vse = VALUE_STRING_EXT_INIT(vs);
*
* Extended value strings can be created at runtime by calling
* value_string_ext_new(<ptr to value_string array>,
* <total number of entries in the value_string_array>,
* <value_string_name>);
* Note: The <total number of entries in the value_string_array> should include
* the {0, NULL} entry.
*/
/* Create a value_string_ext given a ptr to a value_string array and the total
* number of entries. Note that the total number of entries should include the
* required {0, NULL} terminating entry of the array.
* Returns a pointer to an epan-scoped'd and initialized value_string_ext
* struct. */
value_string_ext *
value_string_ext_new(const value_string *vs, guint vs_tot_num_entries,
const gchar *vs_name)
{
value_string_ext *vse;
DISSECTOR_ASSERT (vs_name != NULL);
DISSECTOR_ASSERT (vs_tot_num_entries > 0);
/* Null-terminated value-string ? */
DISSECTOR_ASSERT (vs[vs_tot_num_entries-1].strptr == NULL);
vse = wmem_new(wmem_epan_scope(), value_string_ext);
vse->_vs_p = vs;
vse->_vs_num_entries = vs_tot_num_entries - 1;
/* We set our 'match' function to the init function, which finishes by
* setting the match function properly and then calling it. This is a
* simple way to do lazy initialization of extended value strings.
* The init function also sets up _vs_first_value for us. */
vse->_vs_first_value = 0;
vse->_vs_match2 = _try_val_to_str_ext_init;
vse->_vs_name = vs_name;
return vse;
}
void
value_string_ext_free(value_string_ext *vse)
{
wmem_free(wmem_epan_scope(), vse);
}
/* Like try_val_to_str for extended value strings */
const gchar *
try_val_to_str_ext(const guint32 val, value_string_ext *vse)
{
if (vse) {
const value_string *vs = vse->_vs_match2(val, vse);
if (vs) {
return vs->strptr;
}
}
return NULL;
}
/* Like try_val_to_str_idx for extended value strings */
const gchar *
try_val_to_str_idx_ext(const guint32 val, value_string_ext *vse, gint *idx)
{
if (vse) {
const value_string *vs = vse->_vs_match2(val, vse);
if (vs) {
*idx = (gint) (vs - vse->_vs_p);
return vs->strptr;
}
}
*idx = -1;
return NULL;
}
/* Like val_to_str for extended value strings */
const gchar *
val_to_str_ext(const guint32 val, value_string_ext *vse, const char *fmt)
{
const gchar *ret;
DISSECTOR_ASSERT(fmt != NULL);
ret = try_val_to_str_ext(val, vse);
if (ret != NULL)
return ret;
return wmem_strdup_printf(wmem_packet_scope(), fmt, val);
}
gchar *
val_to_str_ext_wmem(wmem_allocator_t *scope, const guint32 val, value_string_ext *vse, const char *fmt)
{
const gchar *ret;
DISSECTOR_ASSERT(fmt != NULL);
ret = try_val_to_str_ext(val, vse);
if (ret != NULL)
return wmem_strdup(scope, ret);
return wmem_strdup_printf(scope, fmt, val);
}
/* Like val_to_str_const for extended value strings */
const gchar *
val_to_str_ext_const(const guint32 val, value_string_ext *vse,
const char *unknown_str)
{
const gchar *ret;
DISSECTOR_ASSERT(unknown_str != NULL);
ret = try_val_to_str_ext(val, vse);
if (ret != NULL)
return ret;
return unknown_str;
}
/* Fallback linear matching algorithm for extended value strings */
static const value_string *
_try_val_to_str_linear(const guint32 val, value_string_ext *vse)
{
const value_string *vs_p = vse->_vs_p;
guint i;
for (i=0; i<vse->_vs_num_entries; i++) {
if (vs_p[i].value == val)
return &(vs_p[i]);
}
return NULL;
}
/* Constant-time matching algorithm for contiguous extended value strings */
static const value_string *
_try_val_to_str_index(const guint32 val, value_string_ext *vse)
{
guint i;
i = val - vse->_vs_first_value;
if (i < vse->_vs_num_entries) {
g_assert (val == vse->_vs_p[i].value);
return &(vse->_vs_p[i]);
}
return NULL;
}
/* log(n)-time matching algorithm for sorted extended value strings */
static const value_string *
_try_val_to_str_bsearch(const guint32 val, value_string_ext *vse)
{
guint low, i, max;
guint32 item;
for (low = 0, max = vse->_vs_num_entries; low < max; ) {
i = (low + max) / 2;
item = vse->_vs_p[i].value;
if (val < item)
max = i;
else if (val > item)
low = i + 1;
else
return &(vse->_vs_p[i]);
}
return NULL;
}
/* Initializes an extended value string. Behaves like a match function to
* permit lazy initialization of extended value strings.
* - Goes through the value_string array to determine the fastest possible
* access method.
* - Verifies that the value_string contains no NULL string pointers.
* - Verifies that the value_string is terminated by {0, NULL}
*/
const value_string *
_try_val_to_str_ext_init(const guint32 val, value_string_ext *vse)
{
const value_string *vs_p = vse->_vs_p;
const guint vs_num_entries = vse->_vs_num_entries;
/* The matching algorithm used:
* VS_SEARCH - slow sequential search (as in a normal value string)
* VS_BIN_TREE - log(n)-time binary search, the values must be sorted
* VS_INDEX - constant-time index lookup, the values must be contiguous
*/
enum { VS_SEARCH, VS_BIN_TREE, VS_INDEX } type = VS_INDEX;
/* Note: The value_string 'value' is *unsigned*, but we do a little magic
* to help with value strings that have negative values.
*
* { -3, -2, -1, 0, 1, 2 }
* will be treated as "ascending ordered" (although it isn't technically),
* thus allowing constant-time index search
*
* { -3, -2, 0, 1, 2 } and { -3, -2, -1, 0, 2 }
* will both be considered as "out-of-order with gaps", thus falling
* back to the slow linear search
*
* { 0, 1, 2, -3, -2 } and { 0, 2, -3, -2, -1 }
* will be considered "ascending ordered with gaps" thus allowing
* a log(n)-time 'binary' search
*
* If you're confused, think of how negative values are represented, or
* google two's complement.
*/
guint32 prev_value;
guint first_value;
guint i;
DISSECTOR_ASSERT((vs_p[vs_num_entries].value == 0) &&
(vs_p[vs_num_entries].strptr == NULL));
vse->_vs_first_value = vs_p[0].value;
first_value = vs_p[0].value;
prev_value = first_value;
for (i = 0; i < vs_num_entries; i++) {
DISSECTOR_ASSERT(vs_p[i].strptr != NULL);
if ((type == VS_INDEX) && (vs_p[i].value != (i + first_value))) {
type = VS_BIN_TREE;
}
/* XXX: Should check for dups ?? */
if (type == VS_BIN_TREE) {
if (prev_value > vs_p[i].value) {
g_warning("Extended value string '%s' forced to fall back to linear search:\n"
" entry %u, value %u [%#x] < previous entry, value %u [%#x]",
vse->_vs_name, i, vs_p[i].value, vs_p[i].value, prev_value, prev_value);
type = VS_SEARCH;
break;
}
if (first_value > vs_p[i].value) {
g_warning("Extended value string '%s' forced to fall back to linear search:\n"
" entry %u, value %u [%#x] < first entry, value %u [%#x]",
vse->_vs_name, i, vs_p[i].value, vs_p[i].value, first_value, first_value);
type = VS_SEARCH;
break;
}
}
prev_value = vs_p[i].value;
}
switch (type) {
case VS_SEARCH:
vse->_vs_match2 = _try_val_to_str_linear;
break;
case VS_BIN_TREE:
vse->_vs_match2 = _try_val_to_str_bsearch;
break;
case VS_INDEX:
vse->_vs_match2 = _try_val_to_str_index;
break;
default:
g_assert_not_reached();
break;
}
return vse->_vs_match2(val, vse);
}
/* STRING TO STRING MATCHING */
/* string_string is like value_string except the values being matched are
* also strings (instead of unsigned integers) */
/* Like val_to_str except for string_string */
const gchar *
str_to_str(const gchar *val, const string_string *vs, const char *fmt)
{
const gchar *ret;
DISSECTOR_ASSERT(fmt != NULL);
ret = try_str_to_str(val, vs);
if (ret != NULL)
return ret;
return wmem_strdup_printf(wmem_packet_scope(), fmt, val);
}
/* Like try_val_to_str_idx except for string_string */
const gchar *
try_str_to_str_idx(const gchar *val, const string_string *vs, gint *idx)
{
gint i = 0;
if(vs) {
while (vs[i].strptr) {
if (!strcmp(vs[i].value,val)) {
*idx = i;
return(vs[i].strptr);
}
i++;
}
}
*idx = -1;
return NULL;
}
/* Like try_val_to_str except for string_string */
const gchar *
try_str_to_str(const gchar *val, const string_string *vs)
{
gint ignore_me;
return try_str_to_str_idx(val, vs, &ignore_me);
}
/* RANGE TO STRING MATCHING */
/* range_string is like value_string except the values being matched are
* integer ranges (for example, 0-10, 11-19, etc.) instead of single values. */
/* Like val_to_str except for range_string */
const gchar *
rval_to_str(const guint32 val, const range_string *rs, const char *fmt)
{
const gchar *ret = NULL;
DISSECTOR_ASSERT(fmt != NULL);
ret = try_rval_to_str(val, rs);
if(ret != NULL)
return ret;
return wmem_strdup_printf(wmem_packet_scope(), fmt, val);
}
/* Like val_to_str_const except for range_string */
const gchar *
rval_to_str_const(const guint32 val, const range_string *rs,
const char *unknown_str)
{
const gchar *ret = NULL;
DISSECTOR_ASSERT(unknown_str != NULL);
ret = try_rval_to_str(val, rs);
if(ret != NULL)
return ret;
return unknown_str;
}
/* Like try_val_to_str_idx except for range_string */
const gchar *
try_rval_to_str_idx(const guint32 val, const range_string *rs, gint *idx)
{
gint i = 0;
if(rs) {
while(rs[i].strptr) {
if( (val >= rs[i].value_min) && (val <= rs[i].value_max) ) {
*idx = i;
return (rs[i].strptr);
}
i++;
}
}
*idx = -1;
return NULL;
}
/* Like try_val_to_str except for range_string */
const gchar *
try_rval_to_str(const guint32 val, const range_string *rs)
{
gint ignore_me = 0;
return try_rval_to_str_idx(val, rs, &ignore_me);
}
/* MISC */
/* Functions for use by proto_registrar_dump_values(), see proto.c */
gboolean
value_string_ext_validate(const value_string_ext *vse)
{
if (vse == NULL)
return FALSE;
#ifndef _WIN32 /* doesn't work on Windows for refs from another DLL ?? */
if ((vse->_vs_match2 != _try_val_to_str_ext_init) &&
(vse->_vs_match2 != _try_val_to_str_linear) &&
(vse->_vs_match2 != _try_val_to_str_bsearch) &&
(vse->_vs_match2 != _try_val_to_str_index))
return FALSE;
#endif
return TRUE;
}
const gchar *
value_string_ext_match_type_str(const value_string_ext *vse)
{
if (vse->_vs_match2 == _try_val_to_str_ext_init)
return "[Not Initialized]";
if (vse->_vs_match2 == _try_val_to_str_linear)
return "[Linear Search]";
if (vse->_vs_match2 == _try_val_to_str_bsearch)
return "[Binary Search]";
if (vse->_vs_match2 == _try_val_to_str_index)
return "[Direct (indexed) Access]";
return "[Invalid]";
}
/*
* Editor modelines - http://www.wireshark.org/tools/modelines.html
*
* Local variables:
* c-basic-offset: 4
* tab-width: 8
* indent-tabs-mode: nil
* End:
*
* vi: set shiftwidth=4 tabstop=8 expandtab:
* :indentSize=4:tabSize=8:noTabs=true:
*/