blob: 94a4082047b3d4978afda6ed7617f7315c308328 [file] [log] [blame] [edit]
/****************************************************************************
* Copyright (c) 2006-2013,2014 Free Software Foundation, Inc. *
* *
* Permission is hereby granted, free of charge, to any person obtaining a *
* copy of this software and associated documentation files (the *
* "Software"), to deal in the Software without restriction, including *
* without limitation the rights to use, copy, modify, merge, publish, *
* distribute, distribute with modifications, sublicense, and/or sell *
* copies of the Software, and to permit persons to whom the Software is *
* furnished to do so, subject to the following conditions: *
* *
* The above copyright notice and this permission notice shall be included *
* in all copies or substantial portions of the Software. *
* *
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS *
* OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF *
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. *
* IN NO EVENT SHALL THE ABOVE COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, *
* DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR *
* OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR *
* THE USE OR OTHER DEALINGS IN THE SOFTWARE. *
* *
* Except as contained in this notice, the name(s) of the above copyright *
* holders shall not be used in advertising or otherwise to promote the *
* sale, use or other dealings in this Software without prior written *
* authorization. *
****************************************************************************/
/****************************************************************************
* Author: Thomas E. Dickey *
****************************************************************************/
/*
* Iterators for terminal databases.
*/
#include <curses.priv.h>
#include <time.h>
#include <tic.h>
#if USE_HASHED_DB
#include <hashed_db.h>
#endif
MODULE_ID("$Id: db_iterator.c,v 1.39 2014/11/01 14:47:00 tom Exp $")
#define HaveTicDirectory _nc_globals.have_tic_directory
#define KeepTicDirectory _nc_globals.keep_tic_directory
#define TicDirectory _nc_globals.tic_directory
#define my_blob _nc_globals.dbd_blob
#define my_list _nc_globals.dbd_list
#define my_size _nc_globals.dbd_size
#define my_time _nc_globals.dbd_time
#define my_vars _nc_globals.dbd_vars
static void
add_to_blob(const char *text, size_t limit)
{
(void) limit;
if (*text != '\0') {
char *last = my_blob + strlen(my_blob);
if (last != my_blob)
*last++ = NCURSES_PATHSEP;
_nc_STRCPY(last, text, limit);
}
}
static bool
check_existence(const char *name, struct stat *sb)
{
bool result = FALSE;
if (stat(name, sb) == 0
&& (S_ISDIR(sb->st_mode) || S_ISREG(sb->st_mode))) {
result = TRUE;
}
#if USE_HASHED_DB
else if (strlen(name) < PATH_MAX - sizeof(DBM_SUFFIX)) {
char temp[PATH_MAX];
_nc_SPRINTF(temp, _nc_SLIMIT(sizeof(temp)) "%s%s", name, DBM_SUFFIX);
if (stat(temp, sb) == 0 && S_ISREG(sb->st_mode)) {
result = TRUE;
}
}
#endif
return result;
}
/*
* Store the latest value of an environment variable in my_vars[] so we can
* detect if one changes, invalidating the cached search-list.
*/
static bool
update_getenv(const char *name, DBDIRS which)
{
bool result = FALSE;
if (which < dbdLAST) {
char *value;
if ((value = getenv(name)) == 0 || (value = strdup(value)) == 0) {
;
} else if (my_vars[which].name == 0 || strcmp(my_vars[which].name, name)) {
FreeIfNeeded(my_vars[which].value);
my_vars[which].name = name;
my_vars[which].value = value;
result = TRUE;
} else if ((my_vars[which].value != 0) ^ (value != 0)) {
FreeIfNeeded(my_vars[which].value);
my_vars[which].value = value;
result = TRUE;
} else if (value != 0 && strcmp(value, my_vars[which].value)) {
FreeIfNeeded(my_vars[which].value);
my_vars[which].value = value;
result = TRUE;
} else {
free(value);
}
}
return result;
}
static char *
cache_getenv(const char *name, DBDIRS which)
{
char *result = 0;
(void) update_getenv(name, which);
if (which < dbdLAST) {
result = my_vars[which].value;
}
return result;
}
/*
* The cache expires if at least a second has passed since the initial lookup,
* or if one of the environment variables changed.
*
* Only a few applications use multiple lookups of terminal entries, seems that
* aside from bulk I/O such as tic and toe, that leaves interactive programs
* which should not be modifying the terminal databases in a way that would
* invalidate the search-list.
*
* The "1-second" is to allow for user-directed changes outside the program.
*/
static bool
cache_expired(void)
{
bool result = FALSE;
time_t now = time((time_t *) 0);
if (now > my_time) {
result = TRUE;
} else {
DBDIRS n;
for (n = (DBDIRS) 0; n < dbdLAST; ++n) {
if (my_vars[n].name != 0
&& update_getenv(my_vars[n].name, n)) {
result = TRUE;
break;
}
}
}
return result;
}
static void
free_cache(void)
{
FreeAndNull(my_blob);
FreeAndNull(my_list);
}
/*
* Record the "official" location of the terminfo directory, according to
* the place where we're writing to, or the normal default, if not.
*/
NCURSES_EXPORT(const char *)
_nc_tic_dir(const char *path)
{
T(("_nc_tic_dir %s", NonNull(path)));
if (!KeepTicDirectory) {
if (path != 0) {
TicDirectory = path;
HaveTicDirectory = TRUE;
} else if (HaveTicDirectory == 0) {
if (use_terminfo_vars()) {
const char *envp;
if ((envp = getenv("TERMINFO")) != 0)
return _nc_tic_dir(envp);
}
}
}
return TicDirectory ? TicDirectory : TERMINFO;
}
/*
* Special fix to prevent the terminfo directory from being moved after tic
* has chdir'd to it. If we let it be changed, then if $TERMINFO has a
* relative path, we'll lose track of the actual directory.
*/
NCURSES_EXPORT(void)
_nc_keep_tic_dir(const char *path)
{
_nc_tic_dir(path);
KeepTicDirectory = TRUE;
}
/*
* Cleanup.
*/
NCURSES_EXPORT(void)
_nc_last_db(void)
{
if (my_blob != 0 && cache_expired()) {
free_cache();
}
}
/*
* This is a simple iterator which allows the caller to step through the
* possible locations for a terminfo directory. ncurses uses this to find
* terminfo files to read.
*/
NCURSES_EXPORT(const char *)
_nc_next_db(DBDIRS * state, int *offset)
{
const char *result;
(void) offset;
if ((int) *state < my_size
&& my_list != 0
&& my_list[*state] != 0) {
result = my_list[*state];
(*state)++;
} else {
result = 0;
}
if (result != 0) {
T(("_nc_next_db %d %s", *state, result));
}
return result;
}
NCURSES_EXPORT(void)
_nc_first_db(DBDIRS * state, int *offset)
{
bool cache_has_expired = FALSE;
*state = dbdTIC;
*offset = 0;
T(("_nc_first_db"));
/* build a blob containing all of the strings we will use for a lookup
* table.
*/
if (my_blob == 0 || (cache_has_expired = cache_expired())) {
size_t blobsize = 0;
const char *values[dbdLAST];
struct stat *my_stat;
int j, k;
if (cache_has_expired)
free_cache();
for (j = 0; j < dbdLAST; ++j)
values[j] = 0;
/*
* This is the first item in the list, and is used only when tic is
* writing to the database, as a performance improvement.
*/
values[dbdTIC] = TicDirectory;
#if NCURSES_USE_DATABASE
#ifdef TERMINFO_DIRS
values[dbdCfgList] = TERMINFO_DIRS;
#endif
#ifdef TERMINFO
values[dbdCfgOnce] = TERMINFO;
#endif
#endif
#if NCURSES_USE_TERMCAP
values[dbdCfgList2] = TERMPATH;
#endif
if (use_terminfo_vars()) {
#if NCURSES_USE_DATABASE
values[dbdEnvOnce] = cache_getenv("TERMINFO", dbdEnvOnce);
values[dbdHome] = _nc_home_terminfo();
(void) cache_getenv("HOME", dbdHome);
values[dbdEnvList] = cache_getenv("TERMINFO_DIRS", dbdEnvList);
#endif
#if NCURSES_USE_TERMCAP
values[dbdEnvOnce2] = cache_getenv("TERMCAP", dbdEnvOnce2);
/* only use $TERMCAP if it is an absolute path */
if (values[dbdEnvOnce2] != 0
&& *values[dbdEnvOnce2] != '/') {
values[dbdEnvOnce2] = 0;
}
values[dbdEnvList2] = cache_getenv("TERMPATH", dbdEnvList2);
#endif /* NCURSES_USE_TERMCAP */
}
for (j = 0; j < dbdLAST; ++j) {
if (values[j] == 0)
values[j] = "";
blobsize += 2 + strlen(values[j]);
}
my_blob = malloc(blobsize);
if (my_blob != 0) {
*my_blob = '\0';
for (j = 0; j < dbdLAST; ++j) {
add_to_blob(values[j], blobsize);
}
/* Now, build an array which will be pointers to the distinct
* strings in the blob.
*/
blobsize = 2;
for (j = 0; my_blob[j] != '\0'; ++j) {
if (my_blob[j] == NCURSES_PATHSEP)
++blobsize;
}
my_list = typeCalloc(char *, blobsize);
my_stat = typeCalloc(struct stat, blobsize);
if (my_list != 0 && my_stat != 0) {
k = 0;
my_list[k++] = my_blob;
for (j = 0; my_blob[j] != '\0'; ++j) {
if (my_blob[j] == NCURSES_PATHSEP) {
my_blob[j] = '\0';
my_list[k++] = &my_blob[j + 1];
}
}
/*
* Eliminate duplicates from the list.
*/
for (j = 0; my_list[j] != 0; ++j) {
#ifdef TERMINFO
if (*my_list[j] == '\0')
my_list[j] = strdup(TERMINFO);
#endif
for (k = 0; k < j; ++k) {
if (!strcmp(my_list[j], my_list[k])) {
k = j - 1;
while ((my_list[j] = my_list[j + 1]) != 0) {
++j;
}
j = k;
break;
}
}
}
/*
* Eliminate non-existent databases, and those that happen to
* be symlinked to another location.
*/
for (j = 0; my_list[j] != 0; ++j) {
bool found = check_existence(my_list[j], &my_stat[j]);
#if HAVE_LINK
if (found) {
for (k = 0; k < j; ++k) {
if (my_stat[j].st_dev == my_stat[k].st_dev
&& my_stat[j].st_ino == my_stat[k].st_ino) {
found = FALSE;
break;
}
}
}
#endif
if (!found) {
k = j;
while ((my_list[k] = my_list[k + 1]) != 0) {
++k;
}
--j;
}
}
my_size = j;
my_time = time((time_t *) 0);
} else {
FreeAndNull(my_blob);
}
free(my_stat);
}
}
}
#if NO_LEAKS
void
_nc_db_iterator_leaks(void)
{
DBDIRS which;
if (my_blob != 0)
FreeAndNull(my_blob);
if (my_list != 0)
FreeAndNull(my_list);
for (which = 0; (int) which < dbdLAST; ++which) {
my_vars[which].name = 0;
FreeIfNeeded(my_vars[which].value);
my_vars[which].value = 0;
}
}
#endif