fish-shell/src/parse_execution.cpp
ridiculousfish cd9a035f02 Add a string_output_stream_t to collect builtin output
This is used when creating a function; this breaks a dependency on the
more complicated buffered_output_stream_t to ease refactoring.
2021-02-04 14:12:14 -08:00

1613 lines
64 KiB
C++

// Provides the "linkage" between an ast and actual execution structures (job_t, etc.)
#include "config.h" // IWYU pragma: keep
#include "parse_execution.h"
#include <errno.h>
#include <stdarg.h>
#include <stdio.h>
#include <stdlib.h>
#include <termios.h>
#include <unistd.h>
#include <wctype.h>
#include <algorithm>
#include <cwchar>
#include <memory>
#include <string>
#include <type_traits>
#include <vector>
#include "ast.h"
#include "builtin.h"
#include "builtin_function.h"
#include "common.h"
#include "complete.h"
#include "env.h"
#include "event.h"
#include "exec.h"
#include "expand.h"
#include "flog.h"
#include "function.h"
#include "io.h"
#include "job_group.h"
#include "maybe.h"
#include "parse_constants.h"
#include "parse_util.h"
#include "parser.h"
#include "path.h"
#include "proc.h"
#include "reader.h"
#include "timer.h"
#include "tokenizer.h"
#include "trace.h"
#include "util.h"
#include "wildcard.h"
#include "wutil.h"
/// These are the specific statement types that support redirections.
static constexpr bool type_is_redirectable_block(ast::type_t type) {
using t = ast::type_t;
return type == t::block_statement || type == t::if_statement || type == t::switch_statement;
}
static bool specific_statement_type_is_redirectable_block(const ast::node_t &node) {
return type_is_redirectable_block(node.type);
}
/// Get the name of a redirectable block, for profiling purposes.
static wcstring profiling_cmd_name_for_redirectable_block(const ast::node_t &node,
const parsed_source_t &pstree) {
using namespace ast;
assert(specific_statement_type_is_redirectable_block(node));
auto source_range = node.try_source_range();
assert(source_range.has_value() && "No source range for block");
size_t src_end = 0;
switch (node.type) {
case type_t::block_statement: {
const node_t *block_header = node.as<block_statement_t>()->header.get();
switch (block_header->type) {
case type_t::for_header:
src_end = block_header->as<for_header_t>()->semi_nl.source_range().start;
break;
case type_t::while_header:
src_end = block_header->as<while_header_t>()->condition.source_range().end();
break;
case type_t::function_header:
src_end = block_header->as<function_header_t>()->semi_nl.source_range().start;
break;
case type_t::begin_header:
src_end = block_header->as<begin_header_t>()->kw_begin.source_range().end();
break;
default:
DIE("Unexpected block header type");
}
} break;
case type_t::if_statement:
src_end = node.as<if_statement_t>()->if_clause.condition.job.source_range().end();
break;
case type_t::switch_statement:
src_end = node.as<switch_statement_t>()->semi_nl.source_range().start;
break;
default:
DIE("Not a redirectable block type");
break;
}
assert(src_end >= source_range->start && "Invalid source end");
// Get the source for the block, and cut it at the next statement terminator.
wcstring result = pstree.src.substr(source_range->start, src_end - source_range->start);
result.append(L"...");
return result;
}
/// Get a redirection from stderr to stdout (i.e. 2>&1).
static redirection_spec_t get_stderr_merge() {
const wchar_t *stdout_fileno_str = L"1";
return redirection_spec_t{STDERR_FILENO, redirection_mode_t::fd, stdout_fileno_str};
}
parse_execution_context_t::parse_execution_context_t(parsed_source_ref_t pstree,
const operation_context_t &ctx,
cancellation_group_ref_t cancel_group,
io_chain_t block_io)
: pstree(std::move(pstree)),
parser(ctx.parser.get()),
ctx(ctx),
cancel_group(std::move(cancel_group)),
block_io(std::move(block_io)) {}
// Utilities
wcstring parse_execution_context_t::get_source(const ast::node_t &node) const {
return node.source(pstree->src);
}
const ast::decorated_statement_t *
parse_execution_context_t::infinite_recursive_statement_in_job_list(const ast::job_list_t &jobs,
wcstring *out_func_name) const {
// This is a bit fragile. It is a test to see if we are inside of function call, but not inside
// a block in that function call. If, in the future, the rules for what block scopes are pushed
// on function invocation changes, then this check will break.
const block_t *current = parser->block_at_index(0), *parent = parser->block_at_index(1);
bool is_within_function_call =
(current && parent && current->type() == block_type_t::top && parent->is_function_call());
if (!is_within_function_call) {
return nullptr;
}
// Get the function name of the immediate block.
const wcstring &forbidden_function_name = parent->function_name;
// Get the first job in the job list.
const ast::job_conjunction_t *jc = jobs.at(0);
if (!jc) return nullptr;
const ast::job_t *job = &jc->job;
// Helper to return if a statement is infinitely recursive in this function.
auto statement_recurses =
[&](const ast::statement_t &stat) -> const ast::decorated_statement_t * {
// Ignore non-decorated statements like `if`, etc.
const ast::decorated_statement_t *dc =
stat.contents.contents->try_as<ast::decorated_statement_t>();
if (!dc) return nullptr;
// Ignore statements with decorations like 'builtin' or 'command', since those
// are not infinite recursion. In particular that is what enables 'wrapper functions'.
if (dc->decoration() != statement_decoration_t::none) return nullptr;
// Check the command.
wcstring cmd = dc->command.source(pstree->src);
bool forbidden =
!cmd.empty() &&
expand_one(cmd, {expand_flag::skip_cmdsubst, expand_flag::skip_variables}, ctx) &&
cmd == forbidden_function_name;
return forbidden ? dc : nullptr;
};
const ast::decorated_statement_t *infinite_recursive_statement = nullptr;
// Check main statement.
infinite_recursive_statement = statement_recurses(jc->job.statement);
// Check piped remainder.
if (!infinite_recursive_statement) {
for (const ast::job_continuation_t &c : job->continuation) {
if (const auto *s = statement_recurses(c.statement)) {
infinite_recursive_statement = s;
break;
}
}
}
if (infinite_recursive_statement && out_func_name) {
*out_func_name = forbidden_function_name;
}
// may be null
return infinite_recursive_statement;
}
process_type_t parse_execution_context_t::process_type_for_command(
const ast::decorated_statement_t &statement, const wcstring &cmd) const {
enum process_type_t process_type = process_type_t::external;
// Determine the process type, which depends on the statement decoration (command, builtin,
// etc).
switch (statement.decoration()) {
case statement_decoration_t::exec:
process_type = process_type_t::exec;
break;
case statement_decoration_t::command:
process_type = process_type_t::external;
break;
case statement_decoration_t::builtin:
process_type = process_type_t::builtin;
break;
case statement_decoration_t::none:
if (function_exists(cmd, *parser)) {
process_type = process_type_t::function;
} else if (builtin_exists(cmd)) {
process_type = process_type_t::builtin;
} else {
process_type = process_type_t::external;
}
break;
}
return process_type;
}
maybe_t<end_execution_reason_t> parse_execution_context_t::check_end_execution() const {
if (ctx.check_cancel() || check_cancel_from_fish_signal()) {
return end_execution_reason_t::cancelled;
}
const auto &ld = parser->libdata();
if (ld.exit_current_script) {
return end_execution_reason_t::cancelled;
}
if (ld.returning) {
return end_execution_reason_t::control_flow;
}
if (ld.loop_status != loop_status_t::normals) {
return end_execution_reason_t::control_flow;
}
return none();
}
/// Return whether the job contains a single statement, of block type, with no redirections.
bool parse_execution_context_t::job_is_simple_block(const ast::job_t &job) const {
using namespace ast;
// Must be no pipes.
if (!job.continuation.empty()) {
return false;
}
// Helper to check if an argument_or_redirection_list_t has no redirections.
auto no_redirs = [](const argument_or_redirection_list_t &list) -> bool {
for (const argument_or_redirection_t &val : list) {
if (val.is_redirection()) return false;
}
return true;
};
// Check if we're a block statement with redirections. We do it this obnoxious way to preserve
// type safety (in case we add more specific statement types).
const node_t &ss = *job.statement.contents.contents;
switch (ss.type) {
case type_t::block_statement:
return no_redirs(ss.as<block_statement_t>()->args_or_redirs);
case type_t::switch_statement:
return no_redirs(ss.as<switch_statement_t>()->args_or_redirs);
case type_t::if_statement:
return no_redirs(ss.as<if_statement_t>()->args_or_redirs);
case type_t::not_statement:
case type_t::decorated_statement:
// not block statements
return false;
default:
assert(0 && "Unexpected child block type");
return false;
}
}
end_execution_reason_t parse_execution_context_t::run_if_statement(
const ast::if_statement_t &statement, const block_t *associated_block) {
using namespace ast;
using job_list_t = ast::job_list_t;
end_execution_reason_t result = end_execution_reason_t::ok;
// We have a sequence of if clauses, with a final else, resulting in a single job list that we
// execute.
const job_list_t *job_list_to_execute = nullptr;
const if_clause_t *if_clause = &statement.if_clause;
// Index of the *next* elseif_clause to test.
const elseif_clause_list_t &elseif_clauses = statement.elseif_clauses;
size_t next_elseif_idx = 0;
// We start with the 'if'.
trace_if_enabled(*parser, L"if");
for (;;) {
if (auto ret = check_end_execution()) {
result = *ret;
break;
}
// An if condition has a job and a "tail" of andor jobs, e.g. "foo ; and bar; or baz".
// Check the condition and the tail. We treat end_execution_reason_t::error here as failure,
// in accordance with historic behavior.
end_execution_reason_t cond_ret =
run_job_conjunction(if_clause->condition, associated_block);
if (cond_ret == end_execution_reason_t::ok) {
cond_ret = run_job_list(if_clause->andor_tail, associated_block);
}
const bool take_branch =
(cond_ret == end_execution_reason_t::ok) && parser->get_last_status() == EXIT_SUCCESS;
if (take_branch) {
// Condition succeeded.
job_list_to_execute = &if_clause->body;
break;
}
// See if we have an elseif.
const auto *elseif_clause = elseif_clauses.at(next_elseif_idx++);
if (elseif_clause) {
trace_if_enabled(*parser, L"else if");
if_clause = &elseif_clause->if_clause;
} else {
break;
}
}
if (!job_list_to_execute) {
// our ifs and elseifs failed.
// Check our else body.
if (statement.else_clause) {
trace_if_enabled(*parser, L"else");
job_list_to_execute = &statement.else_clause->body;
}
}
if (!job_list_to_execute) {
// 'if' condition failed, no else clause, return 0, we're done.
// No job list means no successful conditions, so return 0 (issue #1443).
parser->set_last_statuses(statuses_t::just(STATUS_CMD_OK));
} else {
// Execute the job list we got.
block_t *ib = parser->push_block(block_t::if_block());
run_job_list(*job_list_to_execute, ib);
if (auto ret = check_end_execution()) {
result = *ret;
}
parser->pop_block(ib);
}
trace_if_enabled(*parser, L"end if");
// It's possible there's a last-minute cancellation (issue #1297).
if (auto ret = check_end_execution()) {
result = *ret;
}
// Otherwise, take the exit status of the job list. Reversal of issue #1061.
return result;
}
end_execution_reason_t parse_execution_context_t::run_begin_statement(
const ast::job_list_t &contents) {
// Basic begin/end block. Push a scope block, run jobs, pop it
trace_if_enabled(*parser, L"begin");
block_t *sb = parser->push_block(block_t::scope_block(block_type_t::begin));
end_execution_reason_t ret = run_job_list(contents, sb);
parser->pop_block(sb);
trace_if_enabled(*parser, L"end begin");
return ret;
}
// Define a function.
end_execution_reason_t parse_execution_context_t::run_function_statement(
const ast::block_statement_t &statement, const ast::function_header_t &header) {
using namespace ast;
// Get arguments.
wcstring_list_t arguments;
ast_args_list_t arg_nodes = get_argument_nodes(header.args);
arg_nodes.insert(arg_nodes.begin(), &header.first_arg);
end_execution_reason_t result =
this->expand_arguments_from_nodes(arg_nodes, &arguments, failglob);
if (result != end_execution_reason_t::ok) {
return result;
}
trace_if_enabled(*parser, L"function", arguments);
null_output_stream_t outs;
string_output_stream_t errs;
io_streams_t streams(outs, errs);
int err_code = 0;
maybe_t<int> err = builtin_function(*parser, streams, arguments, pstree, statement);
if (err) {
err_code = err.value();
parser->libdata().status_count++;
parser->set_last_statuses(statuses_t::just(err_code));
}
const wcstring &errtext = errs.contents();
if (!errtext.empty()) {
return this->report_error(err_code, header, L"%ls", errtext.c_str());
}
return result;
}
end_execution_reason_t parse_execution_context_t::run_block_statement(
const ast::block_statement_t &statement, const block_t *associated_block) {
const ast::node_t &bh = *statement.header.contents;
const ast::job_list_t &contents = statement.jobs;
end_execution_reason_t ret = end_execution_reason_t::ok;
if (const auto *fh = bh.try_as<ast::for_header_t>()) {
ret = run_for_statement(*fh, contents);
} else if (const auto *wh = bh.try_as<ast::while_header_t>()) {
ret = run_while_statement(*wh, contents, associated_block);
} else if (const auto *fh = bh.try_as<ast::function_header_t>()) {
ret = run_function_statement(statement, *fh);
} else if (bh.try_as<ast::begin_header_t>()) {
ret = run_begin_statement(contents);
} else {
FLOGF(error, L"Unexpected block header: %ls\n", bh.describe().c_str());
PARSER_DIE();
}
return ret;
}
end_execution_reason_t parse_execution_context_t::run_for_statement(
const ast::for_header_t &header, const ast::job_list_t &block_contents) {
// Get the variable name: `for var_name in ...`. We expand the variable name. It better result
// in just one.
wcstring for_var_name = header.var_name.source(get_source());
if (!expand_one(for_var_name, expand_flags_t{}, ctx)) {
return report_error(STATUS_EXPAND_ERROR, header.var_name,
FAILED_EXPANSION_VARIABLE_NAME_ERR_MSG, for_var_name.c_str());
}
// Get the contents to iterate over.
wcstring_list_t arguments;
ast_args_list_t arg_nodes = get_argument_nodes(header.args);
end_execution_reason_t ret = this->expand_arguments_from_nodes(arg_nodes, &arguments, nullglob);
if (ret != end_execution_reason_t::ok) {
return ret;
}
auto var = parser->vars().get(for_var_name, ENV_DEFAULT);
if (var && var->read_only()) {
return report_error(STATUS_INVALID_ARGS, header.var_name,
L"You cannot use read-only variable '%ls' in a for loop",
for_var_name.c_str());
}
int retval;
if (var) {
retval = parser->set_var_and_fire(for_var_name, ENV_LOCAL | ENV_USER, var->as_list());
} else {
retval = parser->set_empty_var_and_fire(for_var_name, ENV_LOCAL | ENV_USER);
}
assert(retval == ENV_OK);
if (!valid_var_name(for_var_name)) {
return report_error(STATUS_INVALID_ARGS, header.var_name, BUILTIN_ERR_VARNAME, L"for",
for_var_name.c_str());
}
trace_if_enabled(*parser, L"for", arguments);
block_t *fb = parser->push_block(block_t::for_block());
// Now drive the for loop.
for (const wcstring &val : arguments) {
if (auto reason = check_end_execution()) {
ret = *reason;
break;
}
int retval = parser->set_var_and_fire(for_var_name, ENV_DEFAULT | ENV_USER, val);
assert(retval == ENV_OK && "for loop variable should have been successfully set");
(void)retval;
auto &ld = parser->libdata();
ld.loop_status = loop_status_t::normals;
this->run_job_list(block_contents, fb);
if (check_end_execution() == end_execution_reason_t::control_flow) {
// Handle break or continue.
bool do_break = (ld.loop_status == loop_status_t::breaks);
ld.loop_status = loop_status_t::normals;
if (do_break) {
break;
}
}
}
parser->pop_block(fb);
trace_if_enabled(*parser, L"end for");
return ret;
}
end_execution_reason_t parse_execution_context_t::run_switch_statement(
const ast::switch_statement_t &statement) {
// Get the switch variable.
const wcstring switch_value = get_source(statement.argument);
// Expand it. We need to offset any errors by the position of the string.
completion_list_t switch_values_expanded;
parse_error_list_t errors;
auto expand_ret =
expand_string(switch_value, &switch_values_expanded, expand_flags_t{}, ctx, &errors);
parse_error_offset_source_start(&errors, statement.argument.range.start);
switch (expand_ret.result) {
case expand_result_t::error:
return report_errors(expand_ret.status, errors);
case expand_result_t::cancel:
return end_execution_reason_t::cancelled;
case expand_result_t::wildcard_no_match:
return report_error(STATUS_UNMATCHED_WILDCARD, statement.argument, WILDCARD_ERR_MSG,
get_source(statement.argument).c_str());
case expand_result_t::ok:
if (switch_values_expanded.size() > 1) {
return report_error(STATUS_INVALID_ARGS, statement.argument,
_(L"switch: Expected at most one argument, got %lu\n"),
switch_values_expanded.size());
}
break;
}
// If we expanded to nothing, match the empty string.
assert(switch_values_expanded.size() <= 1 && "Should have at most one expansion");
wcstring switch_value_expanded;
if (!switch_values_expanded.empty()) {
switch_value_expanded = std::move(switch_values_expanded.front().completion);
}
end_execution_reason_t result = end_execution_reason_t::ok;
if (trace_enabled(*parser)) trace_argv(*parser, L"switch", {switch_value_expanded});
block_t *sb = parser->push_block(block_t::switch_block());
// Expand case statements.
const ast::case_item_t *matching_case_item = nullptr;
for (const ast::case_item_t &case_item : statement.cases) {
if (auto ret = check_end_execution()) {
result = *ret;
break;
}
// Expand arguments. A case item list may have a wildcard that fails to expand to
// anything. We also report case errors, but don't stop execution; i.e. a case item that
// contains an unexpandable process will report and then fail to match.
ast_args_list_t arg_nodes = get_argument_nodes(case_item.arguments);
wcstring_list_t case_args;
end_execution_reason_t case_result =
this->expand_arguments_from_nodes(arg_nodes, &case_args, failglob);
if (case_result == end_execution_reason_t::ok) {
for (const wcstring &arg : case_args) {
// Unescape wildcards so they can be expanded again.
wcstring unescaped_arg = parse_util_unescape_wildcards(arg);
bool match = wildcard_match(switch_value_expanded, unescaped_arg);
// If this matched, we're done.
if (match) {
matching_case_item = &case_item;
break;
}
}
}
if (matching_case_item) break;
}
if (matching_case_item) {
// Success, evaluate the job list.
assert(result == end_execution_reason_t::ok && "Expected success");
result = this->run_job_list(matching_case_item->body, sb);
}
parser->pop_block(sb);
trace_if_enabled(*parser, L"end switch");
return result;
}
end_execution_reason_t parse_execution_context_t::run_while_statement(
const ast::while_header_t &header, const ast::job_list_t &contents,
const block_t *associated_block) {
end_execution_reason_t ret = end_execution_reason_t::ok;
// "The exit status of the while loop shall be the exit status of the last compound-list-2
// executed, or zero if none was executed."
// Here are more detailed requirements:
// - If we execute the loop body zero times, or the loop body is empty, the status is success.
// - An empty loop body is treated as true, both in the loop condition and after loop exit.
// - The exit status of the last command is visible in the loop condition. (i.e. do not set the
// exit status to true BEFORE executing the loop condition).
// We achieve this by restoring the status if the loop condition fails, plus a special
// affordance for the first condition.
bool first_cond_check = true;
trace_if_enabled(*parser, L"while");
// Run while the condition is true.
for (;;) {
// Save off the exit status if it came from the loop body. We'll restore it if the condition
// is false.
auto cond_saved_status =
first_cond_check ? statuses_t::just(EXIT_SUCCESS) : parser->get_last_statuses();
first_cond_check = false;
// Check the condition.
end_execution_reason_t cond_ret =
this->run_job_conjunction(header.condition, associated_block);
if (cond_ret == end_execution_reason_t::ok) {
cond_ret = run_job_list(header.andor_tail, associated_block);
}
// If the loop condition failed to execute, then exit the loop without modifying the exit
// status. If the loop condition executed with a failure status, restore the status and then
// exit the loop.
if (cond_ret != end_execution_reason_t::ok) {
break;
} else if (parser->get_last_status() != EXIT_SUCCESS) {
parser->set_last_statuses(cond_saved_status);
break;
}
// Check cancellation.
if (auto reason = check_end_execution()) {
ret = *reason;
break;
}
// Push a while block and then check its cancellation reason.
auto &ld = parser->libdata();
ld.loop_status = loop_status_t::normals;
block_t *wb = parser->push_block(block_t::while_block());
this->run_job_list(contents, wb);
auto cancel_reason = this->check_end_execution();
parser->pop_block(wb);
if (cancel_reason == end_execution_reason_t::control_flow) {
// Handle break or continue.
bool do_break = (ld.loop_status == loop_status_t::breaks);
ld.loop_status = loop_status_t::normals;
if (do_break) {
break;
} else {
continue;
}
}
// no_exec means that fish was invoked with -n or --no-execute. If set, we allow the loop to
// not-execute once so its contents can be checked, and then break.
if (no_exec()) {
break;
}
}
trace_if_enabled(*parser, L"end while");
return ret;
}
// Reports an error. Always returns end_execution_reason_t::error.
end_execution_reason_t parse_execution_context_t::report_error(int status, const ast::node_t &node,
const wchar_t *fmt, ...) const {
auto r = node.source_range();
// Create an error.
parse_error_list_t error_list = parse_error_list_t(1);
parse_error_t *error = &error_list.at(0);
error->source_start = r.start;
error->source_length = r.length;
error->code = parse_error_syntax; // hackish
va_list va;
va_start(va, fmt);
error->text = vformat_string(fmt, va);
va_end(va);
return this->report_errors(status, error_list);
}
end_execution_reason_t parse_execution_context_t::report_errors(
int status, const parse_error_list_t &error_list) const {
if (!ctx.check_cancel()) {
if (error_list.empty()) {
FLOG(error, L"Error reported but no error text found.");
}
// Get a backtrace.
wcstring backtrace_and_desc;
parser->get_backtrace(pstree->src, error_list, backtrace_and_desc);
// Print it.
if (!should_suppress_stderr_for_tests()) {
std::fwprintf(stderr, L"%ls", backtrace_and_desc.c_str());
}
// Mark status.
parser->set_last_statuses(statuses_t::just(status));
}
return end_execution_reason_t::error;
}
// static
parse_execution_context_t::ast_args_list_t parse_execution_context_t::get_argument_nodes(
const ast::argument_list_t &args) {
ast_args_list_t result;
for (const ast::argument_t &arg : args) result.push_back(&arg);
return result;
}
// static
parse_execution_context_t::ast_args_list_t parse_execution_context_t::get_argument_nodes(
const ast::argument_or_redirection_list_t &args) {
ast_args_list_t result;
for (const ast::argument_or_redirection_t &v : args) {
if (v.is_argument()) result.push_back(&v.argument());
}
return result;
}
/// Handle the case of command not found.
end_execution_reason_t parse_execution_context_t::handle_command_not_found(
const wcstring &cmd_str, const ast::decorated_statement_t &statement, int err_code) {
// We couldn't find the specified command. This is a non-fatal error. We want to set the exit
// status to 127, which is the standard number used by other shells like bash and zsh.
const wchar_t *const cmd = cmd_str.c_str();
if (err_code != ENOENT) {
return this->report_error(STATUS_NOT_EXECUTABLE, statement,
_(L"The file '%ls' is not executable by this user"), cmd);
} else {
// Handle unrecognized commands with standard command not found handler that can make better
// error messages.
wcstring_list_t event_args;
{
ast_args_list_t args = get_argument_nodes(statement.args_or_redirs);
end_execution_reason_t arg_result =
this->expand_arguments_from_nodes(args, &event_args, failglob);
if (arg_result != end_execution_reason_t::ok) {
return arg_result;
}
event_args.insert(event_args.begin(), cmd_str);
}
wcstring buffer;
wcstring error;
// Redirect to stderr
auto io = io_chain_t{};
io.append_from_specs({redirection_spec_t{STDOUT_FILENO, redirection_mode_t::fd, L"2"}},
L"");
if (function_exists(L"fish_command_not_found", *parser)) {
buffer = L"fish_command_not_found";
for (const wcstring &arg : event_args) {
buffer.push_back(L' ');
buffer.append(escape_string(arg, ESCAPE_ALL));
}
auto prev_statuses = parser->get_last_statuses();
event_t event(event_type_t::generic);
event.desc.str_param1 = L"fish_command_not_found";
block_t *b = parser->push_block(block_t::event_block(event));
parser->eval(buffer, io);
parser->pop_block(b);
parser->set_last_statuses(std::move(prev_statuses));
} else {
// If we have no handler, just print it as a normal error.
error = _(L"Unknown command:");
if (!event_args.empty()) {
error.push_back(L' ');
error.append(escape_string(event_args[0], ESCAPE_ALL));
}
}
// Here we want to report an error (so it shows a backtrace).
// If the handler printed text, that's already shown, so error will be empty.
return this->report_error(STATUS_CMD_UNKNOWN, statement, error.c_str());
}
}
end_execution_reason_t parse_execution_context_t::expand_command(
const ast::decorated_statement_t &statement, wcstring *out_cmd,
wcstring_list_t *out_args) const {
// Here we're expanding a command, for example $HOME/bin/stuff or $randomthing. The first
// completion becomes the command itself, everything after becomes arguments. Command
// substitutions are not supported.
parse_error_list_t errors;
// Get the unexpanded command string. We expect to always get it here.
wcstring unexp_cmd = get_source(statement.command);
size_t pos_of_command_token = statement.command.range.start;
// Expand the string to produce completions, and report errors.
expand_result_t expand_err =
expand_to_command_and_args(unexp_cmd, ctx, out_cmd, out_args, &errors);
if (expand_err == expand_result_t::error) {
// Issue #5812 - the expansions were done on the command token,
// excluding prefixes such as " " or "if ".
// This means that the error positions are relative to the beginning
// of the token; we need to make them relative to the original source.
parse_error_offset_source_start(&errors, pos_of_command_token);
return report_errors(STATUS_ILLEGAL_CMD, errors);
} else if (expand_err == expand_result_t::wildcard_no_match) {
return report_error(STATUS_UNMATCHED_WILDCARD, statement, WILDCARD_ERR_MSG,
get_source(statement).c_str());
}
assert(expand_err == expand_result_t::ok);
// Complain if the resulting expansion was empty, or expanded to an empty string.
// For no-exec it's okay, as we can't really perform the expansion.
if (out_cmd->empty() && !no_exec()) {
return this->report_error(STATUS_ILLEGAL_CMD, statement,
_(L"The expanded command was empty."));
}
return end_execution_reason_t::ok;
}
/// Creates a 'normal' (non-block) process.
end_execution_reason_t parse_execution_context_t::populate_plain_process(
job_t *job, process_t *proc, const ast::decorated_statement_t &statement) {
assert(job != nullptr);
assert(proc != nullptr);
// We may decide that a command should be an implicit cd.
bool use_implicit_cd = false;
// Get the command and any arguments due to expanding the command.
wcstring cmd;
wcstring_list_t args_from_cmd_expansion;
auto ret = expand_command(statement, &cmd, &args_from_cmd_expansion);
if (ret != end_execution_reason_t::ok) {
return ret;
}
// For no-exec, having an empty command is okay. We can't do anything more with it tho.
if (no_exec()) return end_execution_reason_t::ok;
assert(!cmd.empty() && "expand_command should not produce an empty command");
// Determine the process type.
enum process_type_t process_type = process_type_for_command(statement, cmd);
wcstring path_to_external_command;
if (process_type == process_type_t::external || process_type == process_type_t::exec) {
// Determine the actual command. This may be an implicit cd.
bool has_command = path_get_path(cmd, &path_to_external_command, parser->vars());
// If there was no command, then we care about the value of errno after checking for it, to
// distinguish between e.g. no file vs permissions problem.
const int no_cmd_err_code = errno;
// If the specified command does not exist, and is undecorated, try using an implicit cd.
if (!has_command && statement.decoration() == statement_decoration_t::none) {
// Implicit cd requires an empty argument and redirection list.
if (statement.args_or_redirs.empty()) {
// Ok, no arguments or redirections; check to see if the command is a directory.
use_implicit_cd =
path_as_implicit_cd(cmd, parser->vars().get_pwd_slash(), parser->vars())
.has_value();
}
}
if (!has_command && !use_implicit_cd) {
// No command. If we're --no-execute return okay - it might be a function.
if (no_exec()) return end_execution_reason_t::ok;
return this->handle_command_not_found(cmd, statement, no_cmd_err_code);
}
}
// Produce the full argument list and the set of IO redirections.
wcstring_list_t cmd_args;
redirection_spec_list_t redirections;
if (use_implicit_cd) {
// Implicit cd is simple.
cmd_args = {L"cd", cmd};
path_to_external_command.clear();
// If we have defined a wrapper around cd, use it, otherwise use the cd builtin.
process_type =
function_exists(L"cd", *parser) ? process_type_t::function : process_type_t::builtin;
} else {
// Not implicit cd.
const globspec_t glob_behavior = (cmd == L"set" || cmd == L"count") ? nullglob : failglob;
// Form the list of arguments. The command is the first argument, followed by any arguments
// from expanding the command, followed by the argument nodes themselves. E.g. if the
// command is '$gco foo' and $gco is git checkout.
cmd_args.push_back(cmd);
cmd_args.insert(cmd_args.end(), args_from_cmd_expansion.begin(),
args_from_cmd_expansion.end());
ast_args_list_t arg_nodes = get_argument_nodes(statement.args_or_redirs);
end_execution_reason_t arg_result =
this->expand_arguments_from_nodes(arg_nodes, &cmd_args, glob_behavior);
if (arg_result != end_execution_reason_t::ok) {
return arg_result;
}
// The set of IO redirections that we construct for the process.
auto reason = this->determine_redirections(statement.args_or_redirs, &redirections);
if (reason != end_execution_reason_t::ok) {
return reason;
}
// Determine the process type.
process_type = process_type_for_command(statement, cmd);
}
// Populate the process.
proc->type = process_type;
proc->set_argv(cmd_args);
proc->set_redirection_specs(std::move(redirections));
proc->actual_cmd = std::move(path_to_external_command);
return end_execution_reason_t::ok;
}
// Determine the list of arguments, expanding stuff. Reports any errors caused by expansion. If we
// have a wildcard that could not be expanded, report the error and continue.
end_execution_reason_t parse_execution_context_t::expand_arguments_from_nodes(
const ast_args_list_t &argument_nodes, wcstring_list_t *out_arguments,
globspec_t glob_behavior) {
// Get all argument nodes underneath the statement. We guess we'll have that many arguments (but
// may have more or fewer, if there are wildcards involved).
out_arguments->reserve(out_arguments->size() + argument_nodes.size());
completion_list_t arg_expanded;
for (const ast::argument_t *arg_node : argument_nodes) {
// Expect all arguments to have source.
assert(arg_node->has_source() && "Argument should have source");
// Expand this string.
parse_error_list_t errors;
arg_expanded.clear();
auto expand_ret =
expand_string(get_source(*arg_node), &arg_expanded, expand_flags_t{}, ctx, &errors);
parse_error_offset_source_start(&errors, arg_node->range.start);
switch (expand_ret.result) {
case expand_result_t::error: {
return this->report_errors(expand_ret.status, errors);
}
case expand_result_t::cancel: {
return end_execution_reason_t::cancelled;
}
case expand_result_t::wildcard_no_match: {
if (glob_behavior == failglob) {
// For no_exec, ignore the error - this might work at runtime.
if (no_exec()) return end_execution_reason_t::ok;
// Report the unmatched wildcard error and stop processing.
return report_error(STATUS_UNMATCHED_WILDCARD, *arg_node, WILDCARD_ERR_MSG,
get_source(*arg_node).c_str());
}
break;
}
case expand_result_t::ok: {
break;
}
default: {
DIE("unexpected expand_string() return value");
}
}
// Now copy over any expanded arguments. Use std::move() to avoid extra allocations; this
// is called very frequently.
out_arguments->reserve(out_arguments->size() + arg_expanded.size());
for (completion_t &new_arg : arg_expanded) {
out_arguments->push_back(std::move(new_arg.completion));
}
}
// We may have received a cancellation during this expansion.
if (auto ret = check_end_execution()) {
return *ret;
}
return end_execution_reason_t::ok;
}
end_execution_reason_t parse_execution_context_t::determine_redirections(
const ast::argument_or_redirection_list_t &list, redirection_spec_list_t *out_redirections) {
// Get all redirection nodes underneath the statement.
for (const ast::argument_or_redirection_t &arg_or_redir : list) {
if (!arg_or_redir.is_redirection()) continue;
const ast::redirection_t &redir_node = arg_or_redir.redirection();
maybe_t<pipe_or_redir_t> oper = pipe_or_redir_t::from_string(get_source(redir_node.oper));
if (!oper || !oper->is_valid()) {
// TODO: figure out if this can ever happen. If so, improve this error message.
return report_error(STATUS_INVALID_ARGS, redir_node, _(L"Invalid redirection: %ls"),
get_source(redir_node).c_str());
}
// PCA: I can't justify this skip_variables flag. It was like this when I got here.
wcstring target = get_source(redir_node.target);
bool target_expanded =
expand_one(target, no_exec() ? expand_flag::skip_variables : expand_flags_t{}, ctx);
if (!target_expanded || target.empty()) {
// TODO: Improve this error message.
return report_error(STATUS_INVALID_ARGS, redir_node,
_(L"Invalid redirection target: %ls"), target.c_str());
}
// Make a redirection spec from the redirect token.
assert(oper && oper->is_valid() && "expected to have a valid redirection");
redirection_spec_t spec{oper->fd, oper->mode, std::move(target)};
// Validate this spec.
if (spec.mode == redirection_mode_t::fd && !spec.is_close() && !spec.get_target_as_fd()) {
const wchar_t *fmt =
_(L"Requested redirection to '%ls', which is not a valid file descriptor");
return report_error(STATUS_INVALID_ARGS, redir_node, fmt, spec.target.c_str());
}
out_redirections->push_back(std::move(spec));
if (oper->stderr_merge) {
// This was a redirect like &> which also modifies stderr.
// Also redirect stderr to stdout.
out_redirections->push_back(get_stderr_merge());
}
}
return end_execution_reason_t::ok;
}
end_execution_reason_t parse_execution_context_t::populate_not_process(
job_t *job, process_t *proc, const ast::not_statement_t &not_statement) {
auto &flags = job->mut_flags();
flags.negate = !flags.negate;
return this->populate_job_process(job, proc, not_statement.contents, not_statement.variables);
}
template <typename Type>
end_execution_reason_t parse_execution_context_t::populate_block_process(
job_t *job, process_t *proc, const ast::statement_t &statement,
const Type &specific_statement) {
using namespace ast;
// We handle block statements by creating process_type_t::block_node, that will bounce back to
// us when it's time to execute them.
UNUSED(job);
static_assert(Type::AstType == type_t::block_statement ||
Type::AstType == type_t::if_statement ||
Type::AstType == type_t::switch_statement,
"Invalid block process");
// Get the argument or redirections list.
// TODO: args_or_redirs should be available without resolving the statement type.
const argument_or_redirection_list_t *args_or_redirs = nullptr;
// Upcast to permit dropping the 'template' keyword.
const node_t &ss = specific_statement;
switch (Type::AstType) {
case type_t::block_statement:
args_or_redirs = &ss.as<block_statement_t>()->args_or_redirs;
break;
case type_t::if_statement:
args_or_redirs = &ss.as<if_statement_t>()->args_or_redirs;
break;
case type_t::switch_statement:
args_or_redirs = &ss.as<switch_statement_t>()->args_or_redirs;
break;
default:
DIE("Unexpected block node type");
}
assert(args_or_redirs && "Should have args_or_redirs");
redirection_spec_list_t redirections;
auto reason = this->determine_redirections(*args_or_redirs, &redirections);
if (reason == end_execution_reason_t::ok) {
proc->type = process_type_t::block_node;
proc->block_node_source = pstree;
proc->internal_block_node = &statement;
proc->set_redirection_specs(std::move(redirections));
}
return reason;
}
end_execution_reason_t parse_execution_context_t::apply_variable_assignments(
process_t *proc, const ast::variable_assignment_list_t &variable_assignment_list,
const block_t **block) {
if (variable_assignment_list.empty()) return end_execution_reason_t::ok;
*block = parser->push_block(block_t::variable_assignment_block());
for (const ast::variable_assignment_t &variable_assignment : variable_assignment_list) {
const wcstring &source = get_source(variable_assignment);
auto equals_pos = variable_assignment_equals_pos(source);
assert(equals_pos);
const wcstring variable_name = source.substr(0, *equals_pos);
const wcstring expression = source.substr(*equals_pos + 1);
completion_list_t expression_expanded;
parse_error_list_t errors;
// TODO this is mostly copied from expand_arguments_from_nodes, maybe extract to function
auto expand_ret =
expand_string(expression, &expression_expanded, expand_flags_t{}, ctx, &errors);
parse_error_offset_source_start(&errors, variable_assignment.range.start + *equals_pos + 1);
switch (expand_ret.result) {
case expand_result_t::error:
return this->report_errors(expand_ret.status, errors);
case expand_result_t::cancel:
return end_execution_reason_t::cancelled;
case expand_result_t::wildcard_no_match: // nullglob (equivalent to set)
case expand_result_t::ok:
break;
default: {
DIE("unexpected expand_string() return value");
}
}
wcstring_list_t vals;
for (auto &completion : expression_expanded) {
vals.emplace_back(std::move(completion.completion));
}
if (proc) proc->variable_assignments.push_back({variable_name, vals});
parser->set_var_and_fire(variable_name, ENV_LOCAL | ENV_EXPORT, std::move(vals));
}
return end_execution_reason_t::ok;
}
end_execution_reason_t parse_execution_context_t::populate_job_process(
job_t *job, process_t *proc, const ast::statement_t &statement,
const ast::variable_assignment_list_t &variable_assignments) {
using namespace ast;
// Get the "specific statement" which is boolean / block / if / switch / decorated.
const node_t &specific_statement = *statement.contents.contents;
const block_t *block = nullptr;
end_execution_reason_t result =
this->apply_variable_assignments(proc, variable_assignments, &block);
cleanup_t scope([&]() {
if (block) parser->pop_block(block);
});
if (result != end_execution_reason_t::ok) return result;
switch (specific_statement.type) {
case type_t::not_statement: {
result =
this->populate_not_process(job, proc, *specific_statement.as<not_statement_t>());
break;
}
case type_t::block_statement:
result = this->populate_block_process(job, proc, statement,
*specific_statement.as<block_statement_t>());
break;
case type_t::if_statement:
result = this->populate_block_process(job, proc, statement,
*specific_statement.as<if_statement_t>());
break;
case type_t::switch_statement:
result = this->populate_block_process(job, proc, statement,
*specific_statement.as<switch_statement_t>());
break;
case type_t::decorated_statement: {
result = this->populate_plain_process(job, proc,
*specific_statement.as<decorated_statement_t>());
break;
}
default: {
FLOGF(error, L"'%ls' not handled by new parser yet.",
specific_statement.describe().c_str());
PARSER_DIE();
break;
}
}
return result;
}
end_execution_reason_t parse_execution_context_t::populate_job_from_job_node(
job_t *j, const ast::job_t &job_node, const block_t *associated_block) {
UNUSED(associated_block);
// We are going to construct process_t structures for every statement in the job.
// Create processes. Each one may fail.
process_list_t processes;
processes.emplace_back(new process_t());
end_execution_reason_t result = this->populate_job_process(
j, processes.back().get(), job_node.statement, job_node.variables);
// Construct process_ts for job continuations (pipelines).
for (const ast::job_continuation_t &jc : job_node.continuation) {
if (result != end_execution_reason_t::ok) {
break;
}
// Handle the pipe, whose fd may not be the obvious stdout.
auto parsed_pipe = pipe_or_redir_t::from_string(get_source(jc.pipe));
assert(parsed_pipe.has_value() && parsed_pipe->is_pipe && "Failed to parse valid pipe");
if (!parsed_pipe->is_valid()) {
result = report_error(STATUS_INVALID_ARGS, jc.pipe, ILLEGAL_FD_ERR_MSG,
get_source(jc.pipe).c_str());
break;
}
processes.back()->pipe_write_fd = parsed_pipe->fd;
if (parsed_pipe->stderr_merge) {
// This was a pipe like &| which redirects both stdout and stderr.
// Also redirect stderr to stdout.
auto specs = processes.back()->redirection_specs();
specs.push_back(get_stderr_merge());
processes.back()->set_redirection_specs(std::move(specs));
}
// Store the new process (and maybe with an error).
processes.emplace_back(new process_t());
result = this->populate_job_process(j, processes.back().get(), jc.statement, jc.variables);
}
// Inform our processes of who is first and last
processes.front()->is_first_in_job = true;
processes.back()->is_last_in_job = true;
// Return what happened.
if (result == end_execution_reason_t::ok) {
// Link up the processes.
assert(!processes.empty()); //!OCLINT(multiple unary operator)
j->processes = std::move(processes);
}
return result;
}
static bool remove_job(parser_t &parser, job_t *job) {
for (auto j = parser.jobs().begin(); j != parser.jobs().end(); ++j) {
if (j->get() == job) {
parser.jobs().erase(j);
return true;
}
}
return false;
}
/// Decide if a job node should be 'time'd.
/// For historical reasons the 'not' and 'time' prefix are "inside out". That is, it's
/// 'not time cmd'. Note that a time appearing anywhere in the pipeline affects the whole job.
/// `sleep 1 | not time true` will time the whole job!
static bool job_node_wants_timing(const ast::job_t &job_node) {
// Does our job have the job-level time prefix?
if (job_node.time) return true;
// Helper to return true if a node is 'not time ...' or 'not not time...' or...
auto is_timed_not_statement = [](const ast::statement_t &stat) {
const auto *ns = stat.contents->try_as<ast::not_statement_t>();
while (ns) {
if (ns->time) return true;
ns = ns->contents.try_as<ast::not_statement_t>();
}
return false;
};
// Do we have a 'not time ...' anywhere in our pipeline?
if (is_timed_not_statement(job_node.statement)) return true;
for (const ast::job_continuation_t &jc : job_node.continuation) {
if (is_timed_not_statement(jc.statement)) return true;
}
return false;
}
end_execution_reason_t parse_execution_context_t::run_1_job(const ast::job_t &job_node,
const block_t *associated_block) {
if (auto ret = check_end_execution()) {
return *ret;
}
// We definitely do not want to execute anything if we're told we're --no-execute!
if (no_exec()) return end_execution_reason_t::ok;
// Get terminal modes.
struct termios tmodes = {};
if (parser->is_interactive() && tcgetattr(STDIN_FILENO, &tmodes)) {
// Need real error handling here.
wperror(L"tcgetattr");
parser->set_last_statuses(statuses_t::just(STATUS_CMD_ERROR));
return end_execution_reason_t::error;
}
// Increment the eval_level for the duration of this command.
scoped_push<int> saved_eval_level(&parser->eval_level, parser->eval_level + 1);
// Save the node index.
scoped_push<const ast::job_t *> saved_node(&executing_job_node, &job_node);
// Profiling support.
profile_item_t *profile_item = this->parser->create_profile_item();
const auto start_time = profile_item ? profile_item_t::now() : 0;
// When we encounter a block construct (e.g. while loop) in the general case, we create a "block
// process" containing its node. This allows us to handle block-level redirections.
// However, if there are no redirections, then we can just jump into the block directly, which
// is significantly faster.
if (job_is_simple_block(job_node)) {
bool do_time = job_node.time.has_value();
// If no-exec has been given, there is nothing to time.
cleanup_t timer = push_timer(do_time && !no_exec());
const block_t *block = nullptr;
end_execution_reason_t result =
this->apply_variable_assignments(nullptr, job_node.variables, &block);
cleanup_t scope([&]() {
if (block) parser->pop_block(block);
});
const ast::node_t *specific_statement = job_node.statement.contents.get();
assert(specific_statement_type_is_redirectable_block(*specific_statement));
if (result == end_execution_reason_t::ok) {
switch (specific_statement->type) {
case ast::type_t::block_statement: {
result = this->run_block_statement(
*specific_statement->as<ast::block_statement_t>(), associated_block);
break;
}
case ast::type_t::if_statement: {
result = this->run_if_statement(*specific_statement->as<ast::if_statement_t>(),
associated_block);
break;
}
case ast::type_t::switch_statement: {
result = this->run_switch_statement(
*specific_statement->as<ast::switch_statement_t>());
break;
}
default: {
// Other types should be impossible due to the
// specific_statement_type_is_redirectable_block check.
PARSER_DIE();
break;
}
}
}
if (profile_item != nullptr) {
profile_item->duration = profile_item_t::now() - start_time;
profile_item->level = parser->eval_level;
profile_item->cmd =
profiling_cmd_name_for_redirectable_block(*specific_statement, *this->pstree);
profile_item->skipped = false;
}
return result;
}
const auto &ld = parser->libdata();
auto job_control_mode = get_job_control_mode();
bool wants_job_control =
(job_control_mode == job_control_t::all) ||
((job_control_mode == job_control_t::interactive) && parser->is_interactive()) ||
(ctx.job_group && ctx.job_group->wants_job_control());
job_t::properties_t props{};
props.initial_background = job_node.bg.has_value();
props.skip_notification =
ld.is_subshell || ld.is_block || ld.is_event || !parser->is_interactive();
props.from_event_handler = ld.is_event;
props.job_control = wants_job_control;
props.wants_timing = job_node_wants_timing(job_node);
// It's an error to have 'time' in a background job.
if (props.wants_timing && props.initial_background) {
return this->report_error(STATUS_INVALID_ARGS, job_node, ERROR_TIME_BACKGROUND);
}
shared_ptr<job_t> job = std::make_shared<job_t>(props, get_source(job_node));
// We are about to populate a job. One possible argument to the job is a command substitution
// which may be interested in the job that's populating it, via '--on-job-exit caller'. Record
// the job ID here.
scoped_push<internal_job_id_t> caller_id(&parser->libdata().caller_id, job->internal_job_id);
// Populate the job. This may fail for reasons like command_not_found. If this fails, an error
// will have been printed.
end_execution_reason_t pop_result =
this->populate_job_from_job_node(job.get(), job_node, associated_block);
caller_id.restore();
// Clean up the job on failure or cancellation.
if (pop_result == end_execution_reason_t::ok) {
// Resolve the job's group and mark if this job is the first to get it.
job->group = job_group_t::resolve_group_for_job(*job, cancel_group, ctx.job_group);
assert(job->group && "Should not have a null group");
job->mut_flags().is_group_root = (job->group != ctx.job_group);
// Success. Give the job to the parser - it will clean it up.
parser->job_add(job);
// Check to see if this contained any external commands.
bool job_contained_external_command = false;
for (const auto &proc : job->processes) {
if (proc->type == process_type_t::external) {
job_contained_external_command = true;
break;
}
}
// Actually execute the job.
if (!exec_job(*parser, job, block_io)) {
// No process in the job successfully launched.
// Ensure statuses are set (#7540).
if (auto statuses = job->get_statuses()) {
parser->set_last_statuses(statuses.value());
parser->libdata().status_count++;
}
remove_job(*this->parser, job.get());
}
// Update universal variables on external conmmands.
// TODO: justify this, why not on every command?
if (job_contained_external_command) {
parser->vars().universal_barrier();
}
}
if (profile_item != nullptr) {
profile_item->duration = profile_item_t::now() - start_time;
profile_item->level = parser->eval_level;
profile_item->cmd = job ? job->command() : wcstring();
profile_item->skipped = (pop_result != end_execution_reason_t::ok);
}
job_reap(*parser, false); // clean up jobs
return pop_result;
}
end_execution_reason_t parse_execution_context_t::run_job_conjunction(
const ast::job_conjunction_t &job_expr, const block_t *associated_block) {
if (auto reason = check_end_execution()) {
return *reason;
}
end_execution_reason_t result = run_1_job(job_expr.job, associated_block);
for (const ast::job_conjunction_continuation_t &jc : job_expr.continuations) {
if (result != end_execution_reason_t::ok) {
return result;
}
if (auto reason = check_end_execution()) {
return *reason;
}
// Check the conjunction type.
bool skip = false;
switch (jc.conjunction.type) {
case parse_token_type_t::andand:
// AND. Skip if the last job failed.
skip = parser->get_last_status() != 0;
break;
case parse_token_type_t::oror:
// OR. Skip if the last job succeeded.
skip = parser->get_last_status() == 0;
break;
default:
DIE("Unexpected job conjunction type");
}
if (!skip) {
result = run_1_job(jc.job, associated_block);
}
}
return result;
}
end_execution_reason_t parse_execution_context_t::test_and_run_1_job_conjunction(
const ast::job_conjunction_t &jc, const block_t *associated_block) {
// Test this job conjunction if it has an 'and' or 'or' decorator.
// If it passes, then run it.
if (auto reason = check_end_execution()) {
return *reason;
}
// Maybe skip the job if it has a leading and/or.
bool skip = false;
if (jc.decorator.has_value()) {
switch (jc.decorator->kw) {
case parse_keyword_t::kw_and:
// AND. Skip if the last job failed.
skip = parser->get_last_status() != 0;
break;
case parse_keyword_t::kw_or:
// OR. Skip if the last job succeeded.
skip = parser->get_last_status() == 0;
break;
default:
DIE("Unexpected keyword");
}
}
// Skipping is treated as success.
if (skip) {
return end_execution_reason_t::ok;
} else {
return this->run_job_conjunction(jc, associated_block);
}
}
end_execution_reason_t parse_execution_context_t::run_job_list(const ast::job_list_t &job_list_node,
const block_t *associated_block) {
auto result = end_execution_reason_t::ok;
for (const ast::job_conjunction_t &jc : job_list_node) {
result = test_and_run_1_job_conjunction(jc, associated_block);
}
// Returns the result of the last job executed or skipped.
return result;
}
end_execution_reason_t parse_execution_context_t::run_job_list(
const ast::andor_job_list_t &job_list_node, const block_t *associated_block) {
auto result = end_execution_reason_t::ok;
for (const ast::andor_job_t &aoj : job_list_node) {
result = test_and_run_1_job_conjunction(aoj.job, associated_block);
}
// Returns the result of the last job executed or skipped.
return result;
}
end_execution_reason_t parse_execution_context_t::eval_node(const ast::statement_t &statement,
const block_t *associated_block) {
// Note we only expect block-style statements here. No not statements.
enum end_execution_reason_t status = end_execution_reason_t::ok;
const ast::node_t *contents = statement.contents.get();
if (const auto *block = contents->try_as<ast::block_statement_t>()) {
status = this->run_block_statement(*block, associated_block);
} else if (const auto *ifstat = contents->try_as<ast::if_statement_t>()) {
status = this->run_if_statement(*ifstat, associated_block);
} else if (const auto *switchstat = contents->try_as<ast::switch_statement_t>()) {
status = this->run_switch_statement(*switchstat);
} else {
FLOGF(error, L"Unexpected node %ls found in %s", statement.describe().c_str(),
__FUNCTION__);
abort();
}
return status;
}
end_execution_reason_t parse_execution_context_t::eval_node(const ast::job_list_t &job_list,
const block_t *associated_block) {
assert(associated_block && "Null block");
// Check for infinite recursion: a function which immediately calls itself..
wcstring func_name;
if (const auto *infinite_recursive_node =
this->infinite_recursive_statement_in_job_list(job_list, &func_name)) {
// We have an infinite recursion.
return this->report_error(STATUS_CMD_ERROR, *infinite_recursive_node,
INFINITE_FUNC_RECURSION_ERR_MSG, func_name.c_str());
}
// Check for stack overflow. The TOP check ensures we only do this for function calls.
if (associated_block->type() == block_type_t::top && parser->function_stack_is_overflowing()) {
return this->report_error(STATUS_CMD_ERROR, job_list, CALL_STACK_LIMIT_EXCEEDED_ERR_MSG);
}
return this->run_job_list(job_list, associated_block);
}
int parse_execution_context_t::line_offset_of_node(const ast::job_t *node) {
// If we're not executing anything, return -1.
if (!node) {
return -1;
}
// If for some reason we're executing a node without source, return -1.
auto range = node->try_source_range();
if (!range) {
return -1;
}
return this->line_offset_of_character_at_offset(range->start);
}
int parse_execution_context_t::line_offset_of_character_at_offset(size_t offset) {
// Count the number of newlines, leveraging our cache.
assert(offset <= pstree->src.size());
// Easy hack to handle 0.
if (offset == 0) {
return 0;
}
// We want to return (one plus) the number of newlines at offsets less than the given offset.
// cached_lineno_count is the number of newlines at indexes less than cached_lineno_offset.
const wchar_t *str = pstree->src.c_str();
if (offset > cached_lineno_offset) {
size_t i;
for (i = cached_lineno_offset; i < offset && str[i] != L'\0'; i++) {
// Add one for every newline we find in the range [cached_lineno_offset, offset).
if (str[i] == L'\n') {
cached_lineno_count++;
}
}
cached_lineno_offset =
i; // note: i, not offset, in case offset is beyond the length of the string
} else if (offset < cached_lineno_offset) {
// Subtract one for every newline we find in the range [offset, cached_lineno_offset).
for (size_t i = offset; i < cached_lineno_offset; i++) {
if (str[i] == L'\n') {
cached_lineno_count--;
}
}
cached_lineno_offset = offset;
}
return cached_lineno_count;
}
int parse_execution_context_t::get_current_line_number() {
int line_number = -1;
int line_offset = this->line_offset_of_node(this->executing_job_node);
if (line_offset >= 0) {
// The offset is 0 based; the number is 1 based.
line_number = line_offset + 1;
}
return line_number;
}
int parse_execution_context_t::get_current_source_offset() const {
int result = -1;
if (executing_job_node) {
if (auto range = executing_job_node->try_source_range()) {
result = static_cast<int>(range->start);
}
}
return result;
}