static void update_export_array_if_necessary(bool recalc) {
ASSERT_IS_MAIN_THREAD();
if (recalc && !get_proc_had_barrier()) {
set_proc_had_barrier(true);
env_universal_barrier();
}
if (has_changed_exported) {
std::map<wcstring, wcstring> vals;
debug(4, L"env_export_arr() recalc");
get_exported(top, &vals);
if (uvars()) {
const wcstring_list_t uni = uvars()->get_names(true, false);
for (size_t i = 0; i < uni.size(); i++) {
const wcstring &key = uni.at(i);
const env_var_t val = uvars()->get(key);
if (!val.missing() && val != ENV_NULL) {
// Note that std::map::insert does NOT overwrite a value already in the map,
// which we depend on here.
vals.insert(std::pair<wcstring, wcstring>(key, val));
}
}
}
std::vector<std::string> local_export_buffer;
export_func(vals, local_export_buffer);
export_array.set(local_export_buffer);
has_changed_exported = false;
}
}
bool env_exist(const wchar_t *key, env_mode_flags_t mode) {
CHECK(key, false);
const bool has_scope = mode & (ENV_LOCAL | ENV_GLOBAL | ENV_UNIVERSAL);
const bool test_local = !has_scope || (mode & ENV_LOCAL);
const bool test_global = !has_scope || (mode & ENV_GLOBAL);
const bool test_universal = !has_scope || (mode & ENV_UNIVERSAL);
const bool test_exported = (mode & ENV_EXPORT) || !(mode & ENV_UNEXPORT);
const bool test_unexported = (mode & ENV_UNEXPORT) || !(mode & ENV_EXPORT);
if (is_electric(key)) {
// Electric variables all exist, and they are all global. A local or universal version can
// not exist. They are also never exported.
if (test_global && test_unexported) {
return true;
}
return false;
}
if (test_local || test_global) {
const env_node_t *env = test_local ? top : global_env;
while (env != NULL) {
if (env == global_env && !test_global) {
break;
}
var_table_t::const_iterator result = env->env.find(key);
if (result != env->env.end()) {
const var_entry_t &res = result->second;
return res.exportv ? test_exported : test_unexported;
}
env = env->next_scope_to_search();
}
}
if (test_universal) {
if (!get_proc_had_barrier()) {
set_proc_had_barrier(true);
env_universal_barrier();
}
if (uvars() && !uvars()->get(key).missing()) {
return uvars()->get_export(key) ? test_exported : test_unexported;
}
}
return 0;
}
static void update_export_array_if_necessary(bool recalc)
{
ASSERT_IS_MAIN_THREAD();
if (recalc && ! get_proc_had_barrier())
{
set_proc_had_barrier(true);
env_universal_barrier();
}
if (has_changed_exported)
{
std::map<wcstring, wcstring> vals;
size_t i;
debug(4, L"env_export_arr() recalc");
get_exported(top, vals);
wcstring_list_t uni;
env_universal_get_names2(uni, 1, 0);
for (i=0; i<uni.size(); i++)
{
const wcstring &key = uni.at(i);
const wchar_t *val = env_universal_get(key.c_str());
if (wcscmp(val, ENV_NULL))
{
// Note that std::map::insert does NOT overwrite a value already in the map,
// which we depend on here
vals.insert(std::pair<wcstring, wcstring>(key, val));
}
}
std::vector<std::string> local_export_buffer;
export_func(vals, local_export_buffer);
export_array.set(local_export_buffer);
has_changed_exported=false;
}
}
env_var_t env_get_string(const wcstring &key, env_mode_flags_t mode)
{
const bool has_scope = mode & (ENV_LOCAL | ENV_GLOBAL | ENV_UNIVERSAL);
const bool search_local = !has_scope || (mode & ENV_LOCAL);
const bool search_global = !has_scope || (mode & ENV_GLOBAL);
const bool search_universal = !has_scope || (mode & ENV_UNIVERSAL);
const bool search_exported = (mode & ENV_EXPORT) || !(mode & ENV_UNEXPORT);
const bool search_unexported = (mode & ENV_UNEXPORT) || !(mode & ENV_EXPORT);
/* Make the assumption that electric keys can't be shadowed elsewhere, since we currently block that in env_set() */
if (is_electric(key))
{
if (!search_global) return env_var_t::missing_var();
/* Big hack...we only allow getting the history on the main thread. Note that history_t may ask for an environment variable, so don't take the lock here (we don't need it) */
if (key == L"history" && is_main_thread())
{
env_var_t result;
history_t *history = reader_get_history();
if (! history)
{
history = &history_t::history_with_name(L"fish");
}
if (history)
history->get_string_representation(&result, ARRAY_SEP_STR);
return result;
}
else if (key == L"COLUMNS")
{
return to_string(common_get_width());
}
else if (key == L"LINES")
{
return to_string(common_get_height());
}
else if (key == L"status")
{
return to_string(proc_get_last_status());
}
else if (key == L"umask")
{
return format_string(L"0%0.3o", get_umask());
}
// we should never get here unless the electric var list is out of sync
}
if (search_local || search_global) {
/* Lock around a local region */
scoped_lock lock(env_lock);
env_node_t *env = search_local ? top : global_env;
while (env != NULL)
{
const var_entry_t *entry = env->find_entry(key);
if (entry != NULL && (entry->exportv ? search_exported : search_unexported))
{
if (entry->val == ENV_NULL)
{
return env_var_t::missing_var();
}
else
{
return entry->val;
}
}
if (has_scope)
{
if (!search_global || env == global_env) break;
env = global_env;
}
else
{
env = env->next_scope_to_search();
}
}
}
if (!search_universal) return env_var_t::missing_var();
/* Another big hack - only do a universal barrier on the main thread (since it can change variable values)
Make sure we do this outside the env_lock because it may itself call env_get_string */
if (is_main_thread() && ! get_proc_had_barrier())
{
set_proc_had_barrier(true);
env_universal_barrier();
}
if (uvars())
{
env_var_t env_var = uvars()->get(key);
if (env_var == ENV_NULL || !(uvars()->get_export(key) ? search_exported : search_unexported))
{
env_var = env_var_t::missing_var();
}
return env_var;
}
return env_var_t::missing_var();
}
int env_set(const wcstring &key, const wchar_t *val, env_mode_flags_t var_mode)
{
ASSERT_IS_MAIN_THREAD();
bool has_changed_old = has_changed_exported;
bool has_changed_new = false;
int done=0;
if (val && contains(key, L"PWD", L"HOME"))
{
/* Canoncalize our path; if it changes, recurse and try again. */
wcstring val_canonical = val;
path_make_canonical(val_canonical);
if (val != val_canonical)
{
return env_set(key, val_canonical.c_str(), var_mode);
}
}
if ((var_mode & (ENV_LOCAL | ENV_UNIVERSAL)) && (is_read_only(key) || is_electric(key)))
{
return ENV_SCOPE;
}
if ((var_mode & ENV_EXPORT) && is_electric(key))
{
return ENV_SCOPE;
}
if ((var_mode & ENV_USER) && is_read_only(key))
{
return ENV_PERM;
}
if (key == L"umask")
{
wchar_t *end;
/*
Set the new umask
*/
if (val && wcslen(val))
{
errno=0;
long mask = wcstol(val, &end, 8);
if (!errno && (!*end) && (mask <= 0777) && (mask >= 0))
{
umask(mask);
/* Do not actually create a umask variable, on env_get, it will be calculated dynamically */
return 0;
}
}
return ENV_INVALID;
}
/*
Zero element arrays are internaly not coded as null but as this
placeholder string
*/
if (!val)
{
val = ENV_NULL;
}
if (var_mode & ENV_UNIVERSAL)
{
const bool old_export = uvars() && uvars()->get_export(key);
bool new_export;
if (var_mode & ENV_EXPORT)
{
// export
new_export = true;
}
else if (var_mode & ENV_UNEXPORT)
{
// unexport
new_export = false;
}
else
{
// not changing the export
new_export = old_export;
}
if (uvars())
{
uvars()->set(key, val, new_export);
env_universal_barrier();
if (old_export || new_export)
{
mark_changed_exported();
}
}
}
else
{
// Determine the node
env_node_t *preexisting_node = env_get_node(key);
bool preexisting_entry_exportv = false;
if (preexisting_node != NULL)
{
var_table_t::const_iterator result = preexisting_node->env.find(key);
assert(result != preexisting_node->env.end());
const var_entry_t &entry = result->second;
if (entry.exportv)
{
preexisting_entry_exportv = true;
has_changed_new = true;
}
}
env_node_t *node = NULL;
if (var_mode & ENV_GLOBAL)
{
node = global_env;
}
else if (var_mode & ENV_LOCAL)
{
node = top;
}
else if (preexisting_node != NULL)
{
node = preexisting_node;
if ((var_mode & (ENV_EXPORT | ENV_UNEXPORT)) == 0)
{
// use existing entry's exportv
var_mode = preexisting_entry_exportv ? ENV_EXPORT : 0;
}
}
else
{
if (! get_proc_had_barrier())
{
set_proc_had_barrier(true);
env_universal_barrier();
}
if (uvars() && ! uvars()->get(key).missing())
{
bool exportv;
if (var_mode & ENV_EXPORT)
{
exportv = true;
}
else if (var_mode & ENV_UNEXPORT)
{
exportv = false;
}
else
{
exportv = uvars()->get_export(key);
}
uvars()->set(key, val, exportv);
env_universal_barrier();
done = 1;
}
else
{
/*
New variable with unspecified scope. The default
scope is the innermost scope that is shadowing,
which will be either the current function or the
global scope.
*/
node = top;
while (node->next && !node->new_scope)
{
node = node->next;
}
}
}
if (!done)
{
// Set the entry in the node
// Note that operator[] accesses the existing entry, or creates a new one
var_entry_t &entry = node->env[key];
if (entry.exportv)
{
// this variable already existed, and was exported
has_changed_new = true;
}
entry.val = val;
if (var_mode & ENV_EXPORT)
{
// the new variable is exported
entry.exportv = true;
node->exportv = true;
has_changed_new = true;
}
else
{
entry.exportv = false;
}
if (has_changed_old || has_changed_new)
mark_changed_exported();
}
}
event_t ev = event_t::variable_event(key);
ev.arguments.reserve(3);
ev.arguments.push_back(L"VARIABLE");
ev.arguments.push_back(L"SET");
ev.arguments.push_back(key);
// debug( 1, L"env_set: fire events on variable %ls", key );
event_fire(&ev);
// debug( 1, L"env_set: return from event firing" );
react_to_variable_change(key);
return 0;
}
bool env_exist(const wchar_t *key, int mode)
{
env_node_t *env;
const wchar_t *item = NULL;
CHECK(key, false);
/*
Read only variables all exist, and they are all global. A local
version can not exist.
*/
if (!(mode & ENV_LOCAL) && !(mode & ENV_UNIVERSAL))
{
if (is_read_only(key) || is_electric(key))
{
//Such variables are never exported
if (mode & ENV_EXPORT)
{
return false;
}
else if (mode & ENV_UNEXPORT)
{
return true;
}
return true;
}
}
if (!(mode & ENV_UNIVERSAL))
{
env = (mode & ENV_GLOBAL)?global_env:top;
while (env != 0)
{
var_table_t::iterator result = env->env.find(key);
if (result != env->env.end())
{
const var_entry_t &res = result->second;
if (mode & ENV_EXPORT)
{
return res.exportv;
}
else if (mode & ENV_UNEXPORT)
{
return ! res.exportv;
}
return true;
}
if (mode & ENV_LOCAL)
break;
env = env->next_scope_to_search();
}
}
if (!(mode & ENV_LOCAL) && !(mode & ENV_GLOBAL))
{
if (! get_proc_had_barrier())
{
set_proc_had_barrier(true);
env_universal_barrier();
}
item = env_universal_get(key);
if (item != NULL)
{
if (mode & ENV_EXPORT)
{
return env_universal_get_export(key) == 1;
}
else if (mode & ENV_UNEXPORT)
{
return env_universal_get_export(key) == 0;
}
return 1;
}
}
return 0;
}
env_var_t env_get_string(const wcstring &key)
{
/* Big hack...we only allow getting the history on the main thread. Note that history_t may ask for an environment variable, so don't take the lock here (we don't need it) */
const bool is_main = is_main_thread();
if (key == L"history" && is_main)
{
env_var_t result;
history_t *history = reader_get_history();
if (! history)
{
history = &history_t::history_with_name(L"fish");
}
if (history)
history->get_string_representation(result, ARRAY_SEP_STR);
return result;
}
else if (key == L"COLUMNS")
{
return to_string(common_get_width());
}
else if (key == L"LINES")
{
return to_string(common_get_height());
}
else if (key == L"status")
{
return to_string(proc_get_last_status());
}
else if (key == L"umask")
{
return format_string(L"0%0.3o", get_umask());
}
else
{
{
/* Lock around a local region */
scoped_lock lock(env_lock);
env_node_t *env = top;
wcstring result;
while (env != NULL)
{
const var_entry_t *entry = env->find_entry(key);
if (entry != NULL)
{
if (entry->val == ENV_NULL)
{
return env_var_t::missing_var();
}
else
{
return entry->val;
}
}
env = env->next_scope_to_search();
}
}
/* Another big hack - only do a universal barrier on the main thread (since it can change variable values)
Make sure we do this outside the env_lock because it may itself call env_get_string */
if (is_main && ! get_proc_had_barrier())
{
set_proc_had_barrier(true);
env_universal_barrier();
}
const wchar_t *item = env_universal_get(key);
if (!item || (wcscmp(item, ENV_NULL)==0))
{
return env_var_t::missing_var();
}
else
{
return item;
}
}
}
int env_set(const wcstring &key, const wchar_t *val, int var_mode)
{
ASSERT_IS_MAIN_THREAD();
env_node_t *node = NULL;
bool has_changed_old = has_changed_exported;
bool has_changed_new = false;
var_entry_t *e=0;
int done=0;
int is_universal = 0;
if( val && contains( key, L"PWD", L"HOME" ) )
{
/* Canoncalize our path; if it changes, recurse and try again. */
wcstring val_canonical = val;
path_make_canonical(val_canonical);
if (val != val_canonical) {
return env_set( key, val_canonical.c_str(), var_mode );
}
}
if( (var_mode & ENV_USER ) && is_read_only(key) )
{
return ENV_PERM;
}
if (key == L"umask")
{
wchar_t *end;
/*
Set the new umask
*/
if( val && wcslen(val) )
{
errno=0;
long mask = wcstol( val, &end, 8 );
if( !errno && (!*end) && (mask <= 0777) && (mask >= 0) )
{
umask( mask );
}
}
/*
Do not actually create a umask variable, on env_get, it will
be calculated dynamically
*/
return 0;
}
/*
Zero element arrays are internaly not coded as null but as this
placeholder string
*/
if( !val )
{
val = ENV_NULL;
}
if( var_mode & ENV_UNIVERSAL )
{
int exportv = 0;
if( !(var_mode & ENV_EXPORT ) &&
!(var_mode & ENV_UNEXPORT ) )
{
env_universal_get_export( key );
}
else
{
exportv = (var_mode & ENV_EXPORT );
}
env_universal_set(key, val, exportv);
is_universal = 1;
}
else
{
node = env_get_node( key );
if( node )
{
var_table_t::iterator result = node->env.find(key);
assert(result != node->env.end());
e = result->second;
if( e->exportv )
{
has_changed_new = true;
}
}
if( (var_mode & ENV_LOCAL) ||
(var_mode & ENV_GLOBAL) )
{
node = ( var_mode & ENV_GLOBAL )?global_env:top;
}
else
{
if( node )
{
if( !(var_mode & ENV_EXPORT ) &&
!(var_mode & ENV_UNEXPORT ) )
{
var_mode = e->exportv?ENV_EXPORT:0;
}
}
else
{
if( ! get_proc_had_barrier())
{
set_proc_had_barrier(true);
env_universal_barrier();
}
if( env_universal_get( key ) )
{
int exportv = 0;
if( !(var_mode & ENV_EXPORT ) &&
!(var_mode & ENV_UNEXPORT ) )
{
env_universal_get_export( key );
}
else
{
exportv = (var_mode & ENV_EXPORT );
}
env_universal_set(key, val, exportv);
is_universal = 1;
done = 1;
}
else
{
/*
New variable with unspecified scope. The default
scope is the innermost scope that is shadowing,
which will be either the current function or the
global scope.
*/
node = top;
while( node->next && !node->new_scope )
{
node = node->next;
}
}
}
}
if( !done )
{
var_entry_t *old_entry = NULL;
var_table_t::iterator result = node->env.find(key);
if ( result != node->env.end() )
{
old_entry = result->second;
node->env.erase(result);
}
var_entry_t *entry = NULL;
if( old_entry )
{
entry = old_entry;
if( (var_mode & ENV_EXPORT) || entry->exportv )
{
entry->exportv = !!(var_mode & ENV_EXPORT);
has_changed_new = true;
}
}
else
{
entry = new var_entry_t;
if( var_mode & ENV_EXPORT)
{
entry->exportv = 1;
has_changed_new = true;
}
else
{
entry->exportv = 0;
}
}
entry->val = val;
node->env[key] = entry;
if( entry->exportv )
{
node->exportv=1;
}
if (has_changed_old || has_changed_new)
mark_changed_exported();
}
}
if( !is_universal )
{
event_t ev = event_t::variable_event(key);
ev.arguments.reset(new wcstring_list_t);
ev.arguments->push_back(L"VARIABLE");
ev.arguments->push_back(L"SET");
ev.arguments->push_back(key);
// debug( 1, L"env_set: fire events on variable %ls", key );
event_fire( &ev );
// debug( 1, L"env_set: return from event firing" );
ev.arguments.reset(NULL);
}
react_to_variable_change(key);
return 0;
}
/// Executes a process \p in job \j, using the read pipe \p pipe_current_read.
/// If the process pipes to a command, the read end of the created pipe is returned in
/// out_pipe_next_read. \returns true on success, false on exec error.
static bool exec_process_in_job(parser_t &parser, process_t *p, job_t *j,
autoclose_fd_t pipe_current_read,
autoclose_fd_t *out_pipe_next_read, const io_chain_t &all_ios,
size_t stdout_read_limit) {
// The IO chain for this process. It starts with the block IO, then pipes, and then gets any
// from the process.
io_chain_t process_net_io_chain = j->block_io_chain();
// See if we need a pipe.
const bool pipes_to_next_command = !p->is_last_in_job;
// The write end of any pipe we create.
autoclose_fd_t pipe_current_write{};
// The pipes the current process write to and read from. Unfortunately these can't be just
// allocated on the stack, since j->io wants shared_ptr.
//
// The write pipe (destined for stdout) needs to occur before redirections. For example,
// with a redirection like this:
//
// `foo 2>&1 | bar`
//
// what we want to happen is this:
//
// dup2(pipe, stdout)
// dup2(stdout, stderr)
//
// so that stdout and stderr both wind up referencing the pipe.
//
// The read pipe (destined for stdin) is more ambiguous. Imagine a pipeline like this:
//
// echo alpha | cat < beta.txt
//
// Should cat output alpha or beta? bash and ksh output 'beta', tcsh gets it right and
// complains about ambiguity, and zsh outputs both (!). No shells appear to output 'alpha',
// so we match bash here. That would mean putting the pipe first, so that it gets trumped by
// the file redirection.
//
// However, eval does this:
//
// echo "begin; $argv "\n" ;end <&3 3<&-" | source 3<&0
//
// which depends on the redirection being evaluated before the pipe. So the write end of the
// pipe comes first, the read pipe of the pipe comes last. See issue #966.
shared_ptr<io_pipe_t> pipe_write;
shared_ptr<io_pipe_t> pipe_read;
// Write pipe goes first.
if (pipes_to_next_command) {
pipe_write.reset(new io_pipe_t(p->pipe_write_fd, false));
process_net_io_chain.push_back(pipe_write);
}
// The explicit IO redirections associated with the process.
process_net_io_chain.append(p->io_chain());
// Read pipe goes last.
if (!p->is_first_in_job) {
pipe_read.reset(new io_pipe_t(p->pipe_read_fd, true));
// Record the current read in pipe_read.
pipe_read->pipe_fd[0] = pipe_current_read.fd();
process_net_io_chain.push_back(pipe_read);
}
// This call is used so the global environment variable array is regenerated, if needed,
// before the fork. That way, we avoid a lot of duplicate work where EVERY child would need
// to generate it, since that result would not get written back to the parent. This call
// could be safely removed, but it would result in slightly lower performance - at least on
// uniprocessor systems.
if (p->type == EXTERNAL) {
// Apply universal barrier so we have the most recent uvar changes
if (!get_proc_had_barrier()) {
set_proc_had_barrier(true);
env_universal_barrier();
}
env_export_arr();
}
// Set up fds that will be used in the pipe.
if (pipes_to_next_command) {
// debug( 1, L"%ls|%ls" , p->argv[0], p->next->argv[0]);
int local_pipe[2] = {-1, -1};
if (exec_pipe(local_pipe) == -1) {
debug(1, PIPE_ERROR);
wperror(L"pipe");
job_mark_process_as_failed(j, p);
return false;
}
// Ensure our pipe fds not conflict with any fd redirections. E.g. if the process is
// like 'cat <&5' then fd 5 must not be used by the pipe.
if (!pipe_avoid_conflicts_with_io_chain(local_pipe, all_ios)) {
// We failed. The pipes were closed for us.
wperror(L"dup");
job_mark_process_as_failed(j, p);
return false;
}
// This tells the redirection about the fds, but the redirection does not close them.
assert(local_pipe[0] >= 0);
assert(local_pipe[1] >= 0);
memcpy(pipe_write->pipe_fd, local_pipe, sizeof(int) * 2);
// Record our pipes.
pipe_current_write.reset(local_pipe[1]);
out_pipe_next_read->reset(local_pipe[0]);
}
// Execute the process.
switch (p->type) {
case INTERNAL_FUNCTION:
case INTERNAL_BLOCK_NODE: {
if (!exec_block_or_func_process(parser, j, p, all_ios, process_net_io_chain)) {
return false;
}
break;
}
case INTERNAL_BUILTIN: {
io_streams_t builtin_io_streams{stdout_read_limit};
if (!exec_internal_builtin_proc(parser, j, p, pipe_read.get(), process_net_io_chain,
builtin_io_streams)) {
return false;
}
if (!handle_builtin_output(j, p, &process_net_io_chain, builtin_io_streams)) {
return false;
}
break;
}
case EXTERNAL: {
if (!exec_external_command(j, p, process_net_io_chain)) {
return false;
}
break;
}
case INTERNAL_EXEC: {
// We should have handled exec up above.
DIE("INTERNAL_EXEC process found in pipeline, where it should never be. Aborting.");
break;
}
}
return true;
}
