nhyatt/putty-source
1
0
Fork 0
mirror of https://git.tartarus.org/simon/putty.git synced 2025-01-09 09:27:59 +00:00
Code Issues Projects Releases Wiki Activity
3214563d8e
putty-source/conf.c
Simon Tatham 3214563d8e Convert a lot of 'int' variables to 'bool'. 
My normal habit these days, in new code, is to treat int and bool as
_almost_ completely separate types. I'm still willing to use C's
implicit test for zero on an integer (e.g. 'if (!blob.len)' is fine,
no need to spell it out as blob.len != 0), but generally, if a
variable is going to be conceptually a boolean, I like to declare it
bool and assign to it using 'true' or 'false' rather than 0 or 1.

PuTTY is an exception, because it predates the C99 bool, and I've
stuck to its existing coding style even when adding new code to it.
But it's been annoying me more and more, so now that I've decided C99
bool is an acceptable thing to require from our toolchain in the first
place, here's a quite thorough trawl through the source doing
'boolification'. Many variables and function parameters are now typed
as bool rather than int; many assignments of 0 or 1 to those variables
are now spelled 'true' or 'false'.

I managed this thorough conversion with the help of a custom clang
plugin that I wrote to trawl the AST and apply heuristics to point out
where things might want changing. So I've even managed to do a decent
job on parts of the code I haven't looked at in years!

To make the plugin's work easier, I pushed platform front ends
generally in the direction of using standard 'bool' in preference to
platform-specific boolean types like Windows BOOL or GTK's gboolean;
I've left the platform booleans in places they _have_ to be for the
platform APIs to work right, but variables only used by my own code
have been converted wherever I found them.

In a few places there are int values that look very like booleans in
_most_ of the places they're used, but have a rarely-used third value,
or a distinction between different nonzero values that most users
don't care about. In these cases, I've _removed_ uses of 'true' and
'false' for the return values, to emphasise that there's something
more subtle going on than a simple boolean answer:
 - the 'multisel' field in dialog.h's list box structure, for which
   the GTK front end in particular recognises a difference between 1
   and 2 but nearly everything else treats as boolean
 - the 'urgent' parameter to plug_receive, where 1 vs 2 tells you
   something about the specific location of the urgent pointer, but
   most clients only care about 0 vs 'something nonzero'
 - the return value of wc_match, where -1 indicates a syntax error in
   the wildcard.
 - the return values from SSH-1 RSA-key loading functions, which use
   -1 for 'wrong passphrase' and 0 for all other failures (so any
   caller which already knows it's not loading an _encrypted private_
   key can treat them as boolean)
 - term->esc_query, and the 'query' parameter in toggle_mode in
   terminal.c, which _usually_ hold 0 for ESC[123h or 1 for ESC[?123h,
   but can also hold -1 for some other intervening character that we
   don't support.

In a few places there's an integer that I haven't turned into a bool
even though it really _can_ only take values 0 or 1 (and, as above,
tried to make the call sites consistent in not calling those values
true and false), on the grounds that I thought it would make it more
confusing to imply that the 0 value was in some sense 'negative' or
bad and the 1 positive or good:
 - the return value of plug_accepting uses the POSIXish convention of
   0=success and nonzero=error; I think if I made it bool then I'd
   also want to reverse its sense, and that's a job for a separate
   piece of work.
 - the 'screen' parameter to lineptr() in terminal.c, where 0 and 1
   represent the default and alternate screens. There's no obvious
   reason why one of those should be considered 'true' or 'positive'
   or 'success' - they're just indices - so I've left it as int.

ssh_scp_recv had particularly confusing semantics for its previous int
return value: its call sites used '<= 0' to check for error, but it
never actually returned a negative number, just 0 or 1. Now the
function and its call sites agree that it's a bool.

In a couple of places I've renamed variables called 'ret', because I
don't like that name any more - it's unclear whether it means the
return value (in preparation) for the _containing_ function or the
return value received from a subroutine call, and occasionally I've
accidentally used the same variable for both and introduced a bug. So
where one of those got in my way, I've renamed it to 'toret' or 'retd'
(the latter short for 'returned') in line with my usual modern
practice, but I haven't done a thorough job of finding all of them.

Finally, one amusing side effect of doing this is that I've had to
separate quite a few chained assignments. It used to be perfectly fine
to write 'a = b = c = TRUE' when a,b,c were int and TRUE was just a
the 'true' defined by stdbool.h, that idiom provokes a warning from
gcc: 'suggest parentheses around assignment used as truth value'!
2018-11-03 13:45:00 +00:00

594 lines
14 KiB
C
Raw Blame History

/*
* conf.c: implementation of the internal storage format used for
* the configuration of a PuTTY session.
*/
#include <stdio.h>
#include <stddef.h>
#include <assert.h>
#include "tree234.h"
#include "putty.h"
/*
* Enumeration of types used in keys and values.
*/
typedef enum {
TYPE_NONE, TYPE_BOOL, TYPE_INT, TYPE_STR, TYPE_FILENAME, TYPE_FONT
} Type;
/*
* Arrays which allow us to look up the subkey and value types for a
* given primary key id.
*/
#define CONF_SUBKEYTYPE_DEF(valtype, keytype, keyword) TYPE_ ## keytype,
static int subkeytypes[] = { CONFIG_OPTIONS(CONF_SUBKEYTYPE_DEF) };
#define CONF_VALUETYPE_DEF(valtype, keytype, keyword) TYPE_ ## valtype,
static int valuetypes[] = { CONFIG_OPTIONS(CONF_VALUETYPE_DEF) };
/*
* Configuration keys are primarily integers (big enum of all the
* different configurable options); some keys have string-designated
* subkeys, such as the list of environment variables (subkeys
* defined by the variable names); some have integer-designated
* subkeys (wordness, colours, preference lists).
*/
struct key {
int primary;
union {
int i;
char *s;
} secondary;
};
/* Variant form of struct key which doesn't contain dynamic data, used
* for lookups. */
struct constkey {
int primary;
union {
int i;
const char *s;
} secondary;
};
struct value {
union {
bool boolval;
int intval;
char *stringval;
Filename *fileval;
FontSpec *fontval;
} u;
};
struct conf_entry {
struct key key;
struct value value;
};
struct conf_tag {
tree234 *tree;
};
/*
* Because 'struct key' is the first element in 'struct conf_entry',
* it's safe (guaranteed by the C standard) to cast arbitrarily back
* and forth between the two types. Therefore, we only need one
* comparison function, which can double as a main sort function for
* the tree (comparing two conf_entry structures with each other)
* and a search function (looking up an externally supplied key).
*/
static int conf_cmp(void *av, void *bv)
{
struct key *a = (struct key *)av;
struct key *b = (struct key *)bv;
if (a->primary < b->primary)
return -1;
else if (a->primary > b->primary)
return +1;
switch (subkeytypes[a->primary]) {
case TYPE_INT:
if (a->secondary.i < b->secondary.i)
return -1;
else if (a->secondary.i > b->secondary.i)
return +1;
return 0;
case TYPE_STR:
return strcmp(a->secondary.s, b->secondary.s);
default:
return 0;
}
}
static int conf_cmp_constkey(void *av, void *bv)
{
struct key *a = (struct key *)av;
struct constkey *b = (struct constkey *)bv;
if (a->primary < b->primary)
return -1;
else if (a->primary > b->primary)
return +1;
switch (subkeytypes[a->primary]) {
case TYPE_INT:
if (a->secondary.i < b->secondary.i)
return -1;
else if (a->secondary.i > b->secondary.i)
return +1;
return 0;
case TYPE_STR:
return strcmp(a->secondary.s, b->secondary.s);
default:
return 0;
}
}
/*
* Free any dynamic data items pointed to by a 'struct key'. We
* don't free the structure itself, since it's probably part of a
* larger allocated block.
*/
static void free_key(struct key *key)
{
if (subkeytypes[key->primary] == TYPE_STR)
sfree(key->secondary.s);
}
/*
* Copy a 'struct key' into another one, copying its dynamic data
* if necessary.
*/
static void copy_key(struct key *to, struct key *from)
{
to->primary = from->primary;
switch (subkeytypes[to->primary]) {
case TYPE_INT:
to->secondary.i = from->secondary.i;
break;
case TYPE_STR:
to->secondary.s = dupstr(from->secondary.s);
break;
}
}
/*
* Free any dynamic data items pointed to by a 'struct value'. We
* don't free the value itself, since it's probably part of a larger
* allocated block.
*/
static void free_value(struct value *val, int type)
{
if (type == TYPE_STR)
sfree(val->u.stringval);
else if (type == TYPE_FILENAME)
filename_free(val->u.fileval);
else if (type == TYPE_FONT)
fontspec_free(val->u.fontval);
}
/*
* Copy a 'struct value' into another one, copying its dynamic data
* if necessary.
*/
static void copy_value(struct value *to, struct value *from, int type)
{
switch (type) {
case TYPE_BOOL:
to->u.boolval = from->u.boolval;
break;
case TYPE_INT:
to->u.intval = from->u.intval;
break;
case TYPE_STR:
to->u.stringval = dupstr(from->u.stringval);
break;
case TYPE_FILENAME:
to->u.fileval = filename_copy(from->u.fileval);
break;
case TYPE_FONT:
to->u.fontval = fontspec_copy(from->u.fontval);
break;
}
}
/*
* Free an entire 'struct conf_entry' and its dynamic data.
*/
static void free_entry(struct conf_entry *entry)
{
free_key(&entry->key);
free_value(&entry->value, valuetypes[entry->key.primary]);
sfree(entry);
}
Conf *conf_new(void)
{
Conf *conf = snew(struct conf_tag);
conf->tree = newtree234(conf_cmp);
return conf;
}
static void conf_clear(Conf *conf)
{
struct conf_entry *entry;
while ((entry = delpos234(conf->tree, 0)) != NULL)
free_entry(entry);
}
void conf_free(Conf *conf)
{
conf_clear(conf);
freetree234(conf->tree);
sfree(conf);
}
static void conf_insert(Conf *conf, struct conf_entry *entry)
{
struct conf_entry *oldentry = add234(conf->tree, entry);
if (oldentry && oldentry != entry) {
del234(conf->tree, oldentry);
free_entry(oldentry);
oldentry = add234(conf->tree, entry);
assert(oldentry == entry);
}
}
void conf_copy_into(Conf *newconf, Conf *oldconf)
{
struct conf_entry *entry, *entry2;
int i;
conf_clear(newconf);
for (i = 0; (entry = index234(oldconf->tree, i)) != NULL; i++) {
entry2 = snew(struct conf_entry);
copy_key(&entry2->key, &entry->key);
copy_value(&entry2->value, &entry->value,
valuetypes[entry->key.primary]);
add234(newconf->tree, entry2);
}
}
Conf *conf_copy(Conf *oldconf)
{
Conf *newconf = conf_new();
conf_copy_into(newconf, oldconf);
return newconf;
}
bool conf_get_bool(Conf *conf, int primary)
{
struct key key;
struct conf_entry *entry;
assert(subkeytypes[primary] == TYPE_NONE);
assert(valuetypes[primary] == TYPE_BOOL);
key.primary = primary;
entry = find234(conf->tree, &key, NULL);
assert(entry);
return entry->value.u.boolval;
}
int conf_get_int(Conf *conf, int primary)
{
struct key key;
struct conf_entry *entry;
assert(subkeytypes[primary] == TYPE_NONE);
assert(valuetypes[primary] == TYPE_INT);
key.primary = primary;
entry = find234(conf->tree, &key, NULL);
assert(entry);
return entry->value.u.intval;
}
int conf_get_int_int(Conf *conf, int primary, int secondary)
{
struct key key;
struct conf_entry *entry;
assert(subkeytypes[primary] == TYPE_INT);
assert(valuetypes[primary] == TYPE_INT);
key.primary = primary;
key.secondary.i = secondary;
entry = find234(conf->tree, &key, NULL);
assert(entry);
return entry->value.u.intval;
}
char *conf_get_str(Conf *conf, int primary)
{
struct key key;
struct conf_entry *entry;
assert(subkeytypes[primary] == TYPE_NONE);
assert(valuetypes[primary] == TYPE_STR);
key.primary = primary;
entry = find234(conf->tree, &key, NULL);
assert(entry);
return entry->value.u.stringval;
}
char *conf_get_str_str_opt(Conf *conf, int primary, const char *secondary)
{
struct key key;
struct conf_entry *entry;
assert(subkeytypes[primary] == TYPE_STR);
assert(valuetypes[primary] == TYPE_STR);
key.primary = primary;
key.secondary.s = (char *)secondary;
entry = find234(conf->tree, &key, NULL);
return entry ? entry->value.u.stringval : NULL;
}
char *conf_get_str_str(Conf *conf, int primary, const char *secondary)
{
char *ret = conf_get_str_str_opt(conf, primary, secondary);
assert(ret);
return ret;
}
char *conf_get_str_strs(Conf *conf, int primary,
char *subkeyin, char **subkeyout)
{
struct constkey key;
struct conf_entry *entry;
assert(subkeytypes[primary] == TYPE_STR);
assert(valuetypes[primary] == TYPE_STR);
key.primary = primary;
if (subkeyin) {
key.secondary.s = subkeyin;
entry = findrel234(conf->tree, &key, NULL, REL234_GT);
} else {
key.secondary.s = "";
entry = findrel234(conf->tree, &key, conf_cmp_constkey, REL234_GE);
}
if (!entry || entry->key.primary != primary)
return NULL;
*subkeyout = entry->key.secondary.s;
return entry->value.u.stringval;
}
char *conf_get_str_nthstrkey(Conf *conf, int primary, int n)
{
struct constkey key;
struct conf_entry *entry;
int index;
assert(subkeytypes[primary] == TYPE_STR);
assert(valuetypes[primary] == TYPE_STR);
key.primary = primary;
key.secondary.s = "";
entry = findrelpos234(conf->tree, &key, conf_cmp_constkey,
REL234_GE, &index);
if (!entry || entry->key.primary != primary)
return NULL;
entry = index234(conf->tree, index + n);
if (!entry || entry->key.primary != primary)
return NULL;
return entry->key.secondary.s;
}
Filename *conf_get_filename(Conf *conf, int primary)
{
struct key key;
struct conf_entry *entry;
assert(subkeytypes[primary] == TYPE_NONE);
assert(valuetypes[primary] == TYPE_FILENAME);
key.primary = primary;
entry = find234(conf->tree, &key, NULL);
assert(entry);
return entry->value.u.fileval;
}
FontSpec *conf_get_fontspec(Conf *conf, int primary)
{
struct key key;
struct conf_entry *entry;
assert(subkeytypes[primary] == TYPE_NONE);
assert(valuetypes[primary] == TYPE_FONT);
key.primary = primary;
entry = find234(conf->tree, &key, NULL);
assert(entry);
return entry->value.u.fontval;
}
void conf_set_bool(Conf *conf, int primary, bool value)
{
struct conf_entry *entry = snew(struct conf_entry);
assert(subkeytypes[primary] == TYPE_NONE);
assert(valuetypes[primary] == TYPE_BOOL);
entry->key.primary = primary;
entry->value.u.boolval = value;
conf_insert(conf, entry);
}
void conf_set_int(Conf *conf, int primary, int value)
{
struct conf_entry *entry = snew(struct conf_entry);
assert(subkeytypes[primary] == TYPE_NONE);
assert(valuetypes[primary] == TYPE_INT);
entry->key.primary = primary;
entry->value.u.intval = value;
conf_insert(conf, entry);
}
void conf_set_int_int(Conf *conf, int primary,
int secondary, int value)
{
struct conf_entry *entry = snew(struct conf_entry);
assert(subkeytypes[primary] == TYPE_INT);
assert(valuetypes[primary] == TYPE_INT);
entry->key.primary = primary;
entry->key.secondary.i = secondary;
entry->value.u.intval = value;
conf_insert(conf, entry);
}
void conf_set_str(Conf *conf, int primary, const char *value)
{
struct conf_entry *entry = snew(struct conf_entry);
assert(subkeytypes[primary] == TYPE_NONE);
assert(valuetypes[primary] == TYPE_STR);
entry->key.primary = primary;
entry->value.u.stringval = dupstr(value);
conf_insert(conf, entry);
}
void conf_set_str_str(Conf *conf, int primary, const char *secondary,
const char *value)
{
struct conf_entry *entry = snew(struct conf_entry);
assert(subkeytypes[primary] == TYPE_STR);
assert(valuetypes[primary] == TYPE_STR);
entry->key.primary = primary;
entry->key.secondary.s = dupstr(secondary);
entry->value.u.stringval = dupstr(value);
conf_insert(conf, entry);
}
void conf_del_str_str(Conf *conf, int primary, const char *secondary)
{
struct key key;
struct conf_entry *entry;
assert(subkeytypes[primary] == TYPE_STR);
assert(valuetypes[primary] == TYPE_STR);
key.primary = primary;
key.secondary.s = (char *)secondary;
entry = find234(conf->tree, &key, NULL);
if (entry) {
del234(conf->tree, entry);
free_entry(entry);
}
}
void conf_set_filename(Conf *conf, int primary, const Filename *value)
{
struct conf_entry *entry = snew(struct conf_entry);
assert(subkeytypes[primary] == TYPE_NONE);
assert(valuetypes[primary] == TYPE_FILENAME);
entry->key.primary = primary;
entry->value.u.fileval = filename_copy(value);
conf_insert(conf, entry);
}
void conf_set_fontspec(Conf *conf, int primary, const FontSpec *value)
{
struct conf_entry *entry = snew(struct conf_entry);
assert(subkeytypes[primary] == TYPE_NONE);
assert(valuetypes[primary] == TYPE_FONT);
entry->key.primary = primary;
entry->value.u.fontval = fontspec_copy(value);
conf_insert(conf, entry);
}
void conf_serialise(BinarySink *bs, Conf *conf)
{
int i;
struct conf_entry *entry;
for (i = 0; (entry = index234(conf->tree, i)) != NULL; i++) {
put_uint32(bs, entry->key.primary);
switch (subkeytypes[entry->key.primary]) {
case TYPE_INT:
put_uint32(bs, entry->key.secondary.i);
break;
case TYPE_STR:
put_asciz(bs, entry->key.secondary.s);
break;
}
switch (valuetypes[entry->key.primary]) {
case TYPE_BOOL:
put_bool(bs, entry->value.u.boolval);
break;
case TYPE_INT:
put_uint32(bs, entry->value.u.intval);
break;
case TYPE_STR:
put_asciz(bs, entry->value.u.stringval);
break;
case TYPE_FILENAME:
filename_serialise(bs, entry->value.u.fileval);
break;
case TYPE_FONT:
fontspec_serialise(bs, entry->value.u.fontval);
break;
}
}
put_uint32(bs, 0xFFFFFFFFU);
}
bool conf_deserialise(Conf *conf, BinarySource *src)
{
struct conf_entry *entry;
unsigned primary;
while (1) {
primary = get_uint32(src);
if (get_err(src))
return false;
if (primary == 0xFFFFFFFFU)
return true;
if (primary >= N_CONFIG_OPTIONS)
return false;
entry = snew(struct conf_entry);
entry->key.primary = primary;
switch (subkeytypes[entry->key.primary]) {
case TYPE_INT:
entry->key.secondary.i = toint(get_uint32(src));
break;
case TYPE_STR:
entry->key.secondary.s = dupstr(get_asciz(src));
break;
}
switch (valuetypes[entry->key.primary]) {
case TYPE_BOOL:
entry->value.u.boolval = get_bool(src);
break;
case TYPE_INT:
entry->value.u.intval = toint(get_uint32(src));
break;
case TYPE_STR:
entry->value.u.stringval = dupstr(get_asciz(src));
break;
case TYPE_FILENAME:
entry->value.u.fileval = filename_deserialise(src);
break;
case TYPE_FONT:
entry->value.u.fontval = fontspec_deserialise(src);
break;
}
if (get_err(src)) {
free_entry(entry);
return false;
}
conf_insert(conf, entry);
}
}
Reference in New Issue View Git Blame Copy Permalink