fish-shell/src/expand.cpp
Kurtis Rader a928517e95 improve converting strings to ints/longs
The existing code is inconsistent, and in a couple of cases wrong, about
dealing with strings that are not valid ints. For example, there are
locations that call wcstol() and check errno without first setting errno
to zero. Normalize the code to a consistent pattern.  This is mostly to
deal with inconsistencies between BSD, GNU, and other UNIXes.

This does make some syntax more liberal. For example `echo $PATH[1 .. 3]`
is now valid due to uniformly allowing leading and trailing whitespace
around numbers. Whereas prior to this change you would get a "Invalid
index value" error. Contrast this with `echo $PATH[ 1.. 3 ]` which was
valid and still is.
2016-11-25 18:52:15 -08:00

1616 lines
57 KiB
C++

// String expansion functions. These functions perform several kinds of parameter expansion.
// IWYU pragma: no_include <cstddef>
#include "config.h"
#include <errno.h>
#include <pwd.h>
#include <stdarg.h>
#include <stddef.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <wchar.h>
#include <wctype.h>
#include <algorithm>
#ifdef HAVE_SYS_SYSCTL_H
#include <sys/sysctl.h> // IWYU pragma: keep
#endif
#include <assert.h>
#include <vector>
#ifdef SunOS
#include <procfs.h>
#endif
#include <stdio.h>
#include <memory> // IWYU pragma: keep
#if __APPLE__
#include <sys/proc.h>
#else
#include <dirent.h>
#include <sys/stat.h>
#endif
#include "common.h"
#include "complete.h"
#include "env.h"
#include "exec.h"
#include "expand.h"
#include "fallback.h" // IWYU pragma: keep
#include "iothread.h"
#include "parse_constants.h"
#include "parse_util.h"
#include "path.h"
#include "proc.h"
#include "util.h"
#include "wildcard.h"
#include "wutil.h" // IWYU pragma: keep
#ifdef KERN_PROCARGS2
#else
#include "tokenizer.h"
#endif
/// Description for child process.
#define COMPLETE_CHILD_PROCESS_DESC _(L"Child process")
/// Description for non-child process.
#define COMPLETE_PROCESS_DESC _(L"Process")
/// Description for long job.
#define COMPLETE_JOB_DESC _(L"Job")
/// Description for short job. The job command is concatenated.
#define COMPLETE_JOB_DESC_VAL _(L"Job: %ls")
/// Description for the shells own pid.
#define COMPLETE_SELF_DESC _(L"Shell process")
/// Description for the shells own pid.
#define COMPLETE_LAST_DESC _(L"Last background job")
/// String in process expansion denoting ourself.
#define SELF_STR L"self"
/// String in process expansion denoting last background job.
#define LAST_STR L"last"
/// Characters which make a string unclean if they are the first character of the string. See \c
/// expand_is_clean().
#define UNCLEAN_FIRST L"~%"
/// Unclean characters. See \c expand_is_clean().
#define UNCLEAN L"$*?\\\"'({})"
static void remove_internal_separator(wcstring *s, bool conv);
/// Test if the specified argument is clean, i.e. it does not contain any tokens which need to be
/// expanded or otherwise altered. Clean strings can be passed through expand_string and expand_one
/// without changing them. About two thirds of all strings are clean, so skipping expansion on them
/// actually does save a small amount of time, since it avoids multiple memory allocations during
/// the expansion process.
///
/// \param in the string to test
static bool expand_is_clean(const wcstring &in) {
if (in.empty()) return true;
// Test characters that have a special meaning in the first character position.
if (wcschr(UNCLEAN_FIRST, in.at(0)) != NULL) return false;
// Test characters that have a special meaning in any character position.
return in.find_first_of(UNCLEAN) == wcstring::npos;
}
/// Append a syntax error to the given error list.
static void append_syntax_error(parse_error_list_t *errors, size_t source_start, const wchar_t *fmt,
...) {
if (errors != NULL) {
parse_error_t error;
error.source_start = source_start;
error.source_length = 0;
error.code = parse_error_syntax;
va_list va;
va_start(va, fmt);
error.text = vformat_string(fmt, va);
va_end(va);
errors->push_back(error);
}
}
/// Append a cmdsub error to the given error list.
static void append_cmdsub_error(parse_error_list_t *errors, size_t source_start, const wchar_t *fmt,
...) {
if (errors != NULL) {
parse_error_t error;
error.source_start = source_start;
error.source_length = 0;
error.code = parse_error_cmdsubst;
va_list va;
va_start(va, fmt);
error.text = vformat_string(fmt, va);
va_end(va);
errors->push_back(error);
}
}
/// Return the environment variable value for the string starting at \c in.
static env_var_t expand_var(const wchar_t *in) {
if (!in) return env_var_t::missing_var();
return env_get_string(in);
}
/// Test if the specified string does not contain character which can not be used inside a quoted
/// string.
static int is_quotable(const wchar_t *str) {
switch (*str) {
case 0: {
return 1;
}
case L'\n':
case L'\t':
case L'\r':
case L'\b':
case L'\x1b': {
return 0;
}
default: { return is_quotable(str + 1); }
}
return 0;
}
static int is_quotable(const wcstring &str) { return is_quotable(str.c_str()); }
wcstring expand_escape_variable(const wcstring &in) {
wcstring_list_t lst;
wcstring buff;
tokenize_variable_array(in, lst);
size_t size = lst.size();
if (size == 0) {
buff.append(L"''");
} else if (size == 1) {
const wcstring &el = lst.at(0);
if (el.find(L' ') != wcstring::npos && is_quotable(el)) {
buff.append(L"'");
buff.append(el);
buff.append(L"'");
} else {
buff.append(escape_string(el, 1));
}
} else {
for (size_t j = 0; j < lst.size(); j++) {
const wcstring &el = lst.at(j);
if (j) buff.append(L" ");
if (is_quotable(el)) {
buff.append(L"'");
buff.append(el);
buff.append(L"'");
} else {
buff.append(escape_string(el, 1));
}
}
}
return buff;
}
/// Tests if all characters in the wide string are numeric.
static int iswnumeric(const wchar_t *n) {
for (; *n; n++) {
if (*n < L'0' || *n > L'9') {
return 0;
}
}
return 1;
}
/// See if the process described by \c proc matches the commandline \c cmd.
static bool match_pid(const wcstring &cmd, const wchar_t *proc, size_t *offset) {
// Test for a direct match. If the proc string is empty (e.g. the user tries to complete against
// %), then return an offset pointing at the base command. That ensures that you don't see a
// bunch of dumb paths when completing against all processes.
if (proc[0] != L'\0' && wcsncmp(cmd.c_str(), proc, wcslen(proc)) == 0) {
if (offset) *offset = 0;
return true;
}
// Get the command to match against. We're only interested in the last path component.
const wcstring base_cmd = wbasename(cmd);
bool result = string_prefixes_string(proc, base_cmd);
// It's a match. Return the offset within the full command.
if (result && offset) *offset = cmd.size() - base_cmd.size();
return result;
}
/// Helper class for iterating over processes. The names returned have been unescaped (e.g. may
/// include spaces).
#ifdef KERN_PROCARGS2
// BSD / OS X process completions.
class process_iterator_t {
std::vector<pid_t> pids;
size_t idx;
wcstring name_for_pid(pid_t pid);
public:
process_iterator_t();
bool next_process(wcstring *str, pid_t *pid);
};
wcstring process_iterator_t::name_for_pid(pid_t pid) {
wcstring result;
int mib[4], maxarg = 0, numArgs = 0;
size_t size = 0;
char *args = NULL, *stringPtr = NULL;
mib[0] = CTL_KERN;
mib[1] = KERN_ARGMAX;
size = sizeof(maxarg);
if (sysctl(mib, 2, &maxarg, &size, NULL, 0) == -1) {
return result;
}
args = (char *)malloc(maxarg);
if (args == NULL) {
return result;
}
mib[0] = CTL_KERN;
mib[1] = KERN_PROCARGS2;
mib[2] = pid;
size = (size_t)maxarg;
if (sysctl(mib, 3, args, &size, NULL, 0) == -1) {
free(args);
return result;
}
memcpy(&numArgs, args, sizeof(numArgs));
stringPtr = args + sizeof(numArgs);
result = str2wcstring(stringPtr);
free(args);
return result;
}
bool process_iterator_t::next_process(wcstring *out_str, pid_t *out_pid) {
wcstring name;
pid_t pid = 0;
bool result = false;
while (idx < pids.size()) {
pid = pids.at(idx++);
name = name_for_pid(pid);
if (!name.empty()) {
result = true;
break;
}
}
if (result) {
*out_str = name;
*out_pid = pid;
}
return result;
}
process_iterator_t::process_iterator_t() : idx(0) {
int err;
struct kinfo_proc *result;
bool done;
static const int name[] = {CTL_KERN, KERN_PROC, KERN_PROC_ALL, 0};
// Declaring name as const requires us to cast it when passing it to sysctl because the
// prototype doesn't include the const modifier.
size_t length;
// We start by calling sysctl with result == NULL and length == 0. That will succeed, and set
// length to the appropriate length. We then allocate a buffer of that size and call sysctl
// again with that buffer. If that succeeds, we're done. If that fails with ENOMEM, we have to
// throw away our buffer and loop. Note that the loop causes use to call sysctl with NULL
// again; this is necessary because the ENOMEM failure case sets length to the amount of data
// returned, not the amount of data that could have been returned.
result = NULL;
done = false;
do {
assert(result == NULL);
// Call sysctl with a NULL buffer.
length = 0;
err = sysctl((int *)name, (sizeof(name) / sizeof(*name)) - 1, NULL, &length, NULL, 0);
if (err == -1) {
err = errno;
}
// Allocate an appropriately sized buffer based on the results from the previous call.
if (err == 0) {
result = (struct kinfo_proc *)malloc(length);
if (result == NULL) {
err = ENOMEM;
}
}
// Call sysctl again with the new buffer. If we get an ENOMEM error, toss away our buffer
// and start again.
if (err == 0) {
err = sysctl((int *)name, (sizeof(name) / sizeof(*name)) - 1, result, &length, NULL, 0);
if (err == -1) {
err = errno;
}
if (err == 0) {
done = true;
} else if (err == ENOMEM) {
assert(result != NULL);
free(result);
result = NULL;
err = 0;
}
}
} while (err == 0 && !done);
// Clean up and establish post conditions.
if (err == 0 && result != NULL) {
for (size_t idx = 0; idx < length / sizeof(struct kinfo_proc); idx++)
pids.push_back(result[idx].kp_proc.p_pid);
}
if (result) free(result);
}
#else
/// /proc style process completions.
class process_iterator_t {
DIR *dir;
public:
process_iterator_t();
~process_iterator_t();
bool next_process(wcstring *out_str, pid_t *out_pid);
};
process_iterator_t::process_iterator_t(void) { dir = opendir("/proc"); }
process_iterator_t::~process_iterator_t(void) {
if (dir) closedir(dir);
}
bool process_iterator_t::next_process(wcstring *out_str, pid_t *out_pid) {
wcstring cmd;
pid_t pid = 0;
while (cmd.empty()) {
wcstring name;
if (!dir || !wreaddir(dir, name)) break;
if (!iswnumeric(name.c_str())) continue;
wcstring path = wcstring(L"/proc/") + name;
struct stat buf;
if (wstat(path, &buf)) continue;
if (buf.st_uid != getuid()) continue;
// Remember the pid.
pid = fish_wcstoi(name.c_str());
if (errno || pid < 0) {
debug(1, _(L"Unexpected failure to convert pid '%ls' to integer\n"), name.c_str());
}
// The 'cmdline' file exists, it should contain the commandline.
FILE *cmdfile;
if ((cmdfile = wfopen(path + L"/cmdline", "r"))) {
wcstring full_command_line;
fgetws2(&full_command_line, cmdfile);
// The command line needs to be escaped.
cmd = tok_first(full_command_line);
}
#ifdef SunOS
else if ((cmdfile = wfopen(path + L"/psinfo", "r"))) {
psinfo_t info;
if (fread(&info, sizeof(info), 1, cmdfile)) {
// The filename is unescaped.
cmd = str2wcstring(info.pr_fname);
}
}
#endif
if (cmdfile) fclose(cmdfile);
}
bool result = !cmd.empty();
if (result) {
*out_str = cmd;
*out_pid = pid;
}
return result;
}
#endif
// Helper function to do a job search.
struct find_job_data_t {
const wchar_t *proc; // the process to search for - possibly numeric, possibly a name
expand_flags_t flags;
std::vector<completion_t> *completions;
};
/// The following function is invoked on the main thread, because the job list is not thread safe.
/// It should search the job list for something matching the given proc, and then return 1 to stop
/// the search, 0 to continue it.
static int find_job(const struct find_job_data_t *info) {
ASSERT_IS_MAIN_THREAD();
const wchar_t *const proc = info->proc;
const expand_flags_t flags = info->flags;
std::vector<completion_t> &completions = *info->completions;
const job_t *j;
int found = 0;
// If we are not doing tab completion, we first check for the single '%' character, because an
// empty string will pass the numeric check below. But if we are doing tab completion, we want
// all of the job IDs as completion options, not just the last job backgrounded, so we pass this
// first block in favor of the second.
if (wcslen(proc) == 0 && !(flags & EXPAND_FOR_COMPLETIONS)) {
// This is an empty job expansion: '%'. It expands to the last job backgrounded.
job_iterator_t jobs;
while ((j = jobs.next())) {
if (!j->command_is_empty()) {
append_completion(&completions, to_string<long>(j->pgid));
break;
}
}
// You don't *really* want to flip a coin between killing the last process backgrounded and
// all processes, do you? Let's not try other match methods with the solo '%' syntax.
found = 1;
} else if (iswnumeric(proc)) {
// This is a numeric job string, like '%2'.
if (flags & EXPAND_FOR_COMPLETIONS) {
job_iterator_t jobs;
while ((j = jobs.next())) {
wchar_t jid[16];
if (j->command_is_empty()) continue;
swprintf(jid, 16, L"%d", j->job_id);
if (wcsncmp(proc, jid, wcslen(proc)) == 0) {
wcstring desc_buff = format_string(COMPLETE_JOB_DESC_VAL, j->command_wcstr());
append_completion(&completions, jid + wcslen(proc), desc_buff, 0);
}
}
} else {
int jid = fish_wcstoi(proc);
if (!errno && jid > 0) {
j = job_get(jid);
if ((j != 0) && (j->command_wcstr() != 0) && (!j->command_is_empty())) {
append_completion(&completions, to_string<long>(j->pgid));
}
}
}
// Stop here so you can't match a random process name when you're just trying to use job
// control.
found = 1;
}
if (found) {
return found;
}
job_iterator_t jobs;
while ((j = jobs.next())) {
if (j->command_is_empty()) continue;
size_t offset;
if (match_pid(j->command(), proc, &offset)) {
if (flags & EXPAND_FOR_COMPLETIONS) {
append_completion(&completions, j->command_wcstr() + offset + wcslen(proc),
COMPLETE_JOB_DESC, 0);
} else {
append_completion(&completions, to_string<long>(j->pgid));
found = 1;
}
}
}
if (found) {
return found;
}
jobs.reset();
while ((j = jobs.next())) {
process_t *p;
if (j->command_is_empty()) continue;
for (p = j->first_process; p; p = p->next) {
if (p->actual_cmd.empty()) continue;
size_t offset;
if (match_pid(p->actual_cmd, proc, &offset)) {
if (flags & EXPAND_FOR_COMPLETIONS) {
append_completion(&completions, wcstring(p->actual_cmd, offset + wcslen(proc)),
COMPLETE_CHILD_PROCESS_DESC, 0);
} else {
append_completion(&completions, to_string<long>(p->pid), L"", 0);
found = 1;
}
}
}
}
return found;
}
/// Searches for a job with the specified job id, or a job or process which has the string \c proc
/// as a prefix of its commandline. Appends the name of the process as a completion in 'out'.
///
/// If the ACCEPT_INCOMPLETE flag is set, the remaining string for any matches are inserted.
///
/// Otherwise, any job matching the specified string is matched, and the job pgid is returned. If no
/// job matches, all child processes are searched. If no child processes match, and <tt>fish</tt>
/// can understand the contents of the /proc filesystem, all the users processes are searched for
/// matches.
static void find_process(const wchar_t *proc, expand_flags_t flags,
std::vector<completion_t> *out) {
if (!(flags & EXPAND_SKIP_JOBS)) {
const struct find_job_data_t data = {proc, flags, out};
int found = iothread_perform_on_main(find_job, &data);
if (found) {
return;
}
}
// Iterate over all processes.
wcstring process_name;
pid_t process_pid;
process_iterator_t iterator;
while (iterator.next_process(&process_name, &process_pid)) {
size_t offset;
if (match_pid(process_name, proc, &offset)) {
if (flags & EXPAND_FOR_COMPLETIONS) {
append_completion(out, process_name.c_str() + offset + wcslen(proc),
COMPLETE_PROCESS_DESC, 0);
} else {
append_completion(out, to_string<long>(process_pid));
}
}
}
}
/// Process id expansion.
static bool expand_pid(const wcstring &instr_with_sep, expand_flags_t flags,
std::vector<completion_t> *out, parse_error_list_t *errors) {
// Hack. If there's no INTERNAL_SEP and no PROCESS_EXPAND, then there's nothing to do. Check out
// this "null terminated string."
const wchar_t some_chars[] = {INTERNAL_SEPARATOR, PROCESS_EXPAND, L'\0'};
if (instr_with_sep.find_first_of(some_chars) == wcstring::npos) {
// Nothing to do.
append_completion(out, instr_with_sep);
return true;
}
// expand_string calls us with internal separators in instr...sigh.
wcstring instr = instr_with_sep;
remove_internal_separator(&instr, false);
if (instr.empty() || instr.at(0) != PROCESS_EXPAND) {
// Not a process expansion.
append_completion(out, instr);
return true;
}
const wchar_t *const in = instr.c_str();
// We know we are a process expansion now.
assert(in[0] == PROCESS_EXPAND);
if (flags & EXPAND_FOR_COMPLETIONS) {
if (wcsncmp(in + 1, SELF_STR, wcslen(in + 1)) == 0) {
append_completion(out, &SELF_STR[wcslen(in + 1)], COMPLETE_SELF_DESC, 0);
} else if (wcsncmp(in + 1, LAST_STR, wcslen(in + 1)) == 0) {
append_completion(out, &LAST_STR[wcslen(in + 1)], COMPLETE_LAST_DESC, 0);
}
} else {
if (wcscmp((in + 1), SELF_STR) == 0) {
append_completion(out, to_string<long>(getpid()));
return true;
}
if (wcscmp((in + 1), LAST_STR) == 0) {
if (proc_last_bg_pid > 0) {
append_completion(out, to_string<long>(proc_last_bg_pid));
}
return true;
}
}
// This is sort of crummy - find_process doesn't return any indication of success, so instead we
// check to see if it inserted any completions.
const size_t prev_count = out->size();
find_process(in + 1, flags, out);
if (prev_count == out->size() && !(flags & EXPAND_FOR_COMPLETIONS)) {
// We failed to find anything.
append_syntax_error(errors, 1, FAILED_EXPANSION_PROCESS_ERR_MSG,
escape(in + 1, ESCAPE_NO_QUOTED).c_str());
return false;
}
return true;
}
/// Parse an array slicing specification Returns 0 on success. If a parse error occurs, returns the
/// index of the bad token. Note that 0 can never be a bad index because the string always starts
/// with [.
static size_t parse_slice(const wchar_t *in, wchar_t **end_ptr, std::vector<long> &idx,
std::vector<size_t> &source_positions, size_t array_size) {
const long size = (long)array_size;
size_t pos = 1; // skip past the opening square bracket
while (1) {
while (iswspace(in[pos]) || (in[pos] == INTERNAL_SEPARATOR)) pos++;
if (in[pos] == L']') {
pos++;
break;
}
const size_t i1_src_pos = pos;
const wchar_t *end;
long tmp = fish_wcstol(&in[pos], &end);
// We don't test `*end` as is typically done because we expect it to not be the null char.
// Ignore the case of errno==-1 because it means the end char wasn't the null char.
if (errno > 0) {
return pos;
}
// debug( 0, L"Push idx %d", tmp );
long i1 = tmp > -1 ? tmp : (long)array_size + tmp + 1;
pos = end - in;
while (in[pos] == INTERNAL_SEPARATOR) pos++;
if (in[pos] == L'.' && in[pos + 1] == L'.') {
pos += 2;
while (in[pos] == INTERNAL_SEPARATOR) pos++;
const size_t number_start = pos;
long tmp1 = fish_wcstol(&in[pos], &end);
// Ignore the case of errno==-1 because it means the end char wasn't the null char.
if (errno > 0) {
return pos;
}
pos = end - in;
// debug( 0, L"Push range %d %d", tmp, tmp1 );
long i2 = tmp1 > -1 ? tmp1 : size + tmp1 + 1;
// debug( 0, L"Push range idx %d %d", i1, i2 );
short direction = i2 < i1 ? -1 : 1;
for (long jjj = i1; jjj * direction <= i2 * direction; jjj += direction) {
// debug(0, L"Expand range [subst]: %i\n", jjj);
idx.push_back(jjj);
source_positions.push_back(number_start);
}
continue;
}
// debug( 0, L"Push idx %d", tmp );
idx.push_back(i1);
source_positions.push_back(i1_src_pos);
}
if (end_ptr) {
*end_ptr = (wchar_t *)(in + pos);
}
return 0;
}
/// Expand all environment variables in the string *ptr.
///
/// This function is slow, fragile and complicated. There are lots of little corner cases, like
/// $$foo should do a double expansion, $foo$bar should not double expand bar, etc. Also, it's easy
/// to accidentally leak memory on array out of bounds errors an various other situations. All in
/// all, this function should be rewritten, split out into multiple logical units and carefully
/// tested. After that, it can probably be optimized to do fewer memory allocations, fewer string
/// scans and overall just less work. But until that happens, don't edit it unless you know exactly
/// what you are doing, and do proper testing afterwards.
///
/// This function operates on strings backwards, starting at last_idx.
///
/// Note: last_idx is considered to be where it previously finished procesisng. This means it
/// actually starts operating on last_idx-1. As such, to process a string fully, pass string.size()
/// as last_idx instead of string.size()-1.
static int expand_variables(const wcstring &instr, std::vector<completion_t> *out, long last_idx,
parse_error_list_t *errors) {
const size_t insize = instr.size();
// last_idx may be 1 past the end of the string, but no further.
assert(last_idx >= 0 && (size_t)last_idx <= insize);
if (last_idx == 0) {
append_completion(out, instr);
return true;
}
bool is_ok = true;
bool empty = false;
wcstring var_tmp;
// List of indexes.
std::vector<long> var_idx_list;
// Parallel array of source positions of each index in the variable list.
std::vector<size_t> var_pos_list;
// CHECK( out, 0 );
for (long i = last_idx - 1; (i >= 0) && is_ok && !empty; i--) {
const wchar_t c = instr.at(i);
if (c != VARIABLE_EXPAND && c != VARIABLE_EXPAND_SINGLE) {
continue;
}
long var_len;
int is_single = (c == VARIABLE_EXPAND_SINGLE);
size_t start_pos = i + 1;
size_t stop_pos = start_pos;
while (stop_pos < insize) {
const wchar_t nc = instr.at(stop_pos);
if (nc == VARIABLE_EXPAND_EMPTY) {
stop_pos++;
break;
}
if (!wcsvarchr(nc)) break;
stop_pos++;
}
// printf( "Stop for '%c'\n", in[stop_pos]);
var_len = stop_pos - start_pos;
if (var_len == 0) {
if (errors) {
parse_util_expand_variable_error(instr, 0 /* global_token_pos */, i, errors);
}
is_ok = false;
break;
}
var_tmp.append(instr, start_pos, var_len);
env_var_t var_val;
if (var_len == 1 && var_tmp[0] == VARIABLE_EXPAND_EMPTY) {
var_val = env_var_t::missing_var();
} else {
var_val = expand_var(var_tmp.c_str());
}
if (!var_val.missing()) {
int all_vars = 1;
wcstring_list_t var_item_list;
if (is_ok) {
tokenize_variable_array(var_val, var_item_list);
const size_t slice_start = stop_pos;
if (slice_start < insize && instr.at(slice_start) == L'[') {
wchar_t *slice_end;
size_t bad_pos;
all_vars = 0;
const wchar_t *in = instr.c_str();
bad_pos = parse_slice(in + slice_start, &slice_end, var_idx_list, var_pos_list,
var_item_list.size());
if (bad_pos != 0) {
append_syntax_error(errors, stop_pos + bad_pos, L"Invalid index value");
is_ok = false;
break;
}
stop_pos = (slice_end - in);
}
if (!all_vars) {
wcstring_list_t string_values(var_idx_list.size());
for (size_t j = 0; j < var_idx_list.size(); j++) {
long tmp = var_idx_list.at(j);
// Check that we are within array bounds. If not, truncate the list to
// exit.
if (tmp < 1 || (size_t)tmp > var_item_list.size()) {
size_t var_src_pos = var_pos_list.at(j);
// The slice was parsed starting at stop_pos, so we have to add that
// to the error position.
append_syntax_error(errors, slice_start + var_src_pos,
ARRAY_BOUNDS_ERR);
is_ok = false;
var_idx_list.resize(j);
break;
} else {
// Replace each index in var_idx_list inplace with the string value
// at the specified index.
// al_set( var_idx_list, j, wcsdup((const wchar_t *)al_get(
// &var_item_list, tmp-1 ) ) );
string_values.at(j) = var_item_list.at(tmp - 1);
}
}
// string_values is the new var_item_list.
var_item_list.swap(string_values);
}
}
if (!is_ok) {
return is_ok;
}
if (is_single) {
wcstring res(instr, 0, i);
if (i > 0) {
if (instr.at(i - 1) != VARIABLE_EXPAND_SINGLE) {
res.push_back(INTERNAL_SEPARATOR);
} else if (var_item_list.empty() || var_item_list.front().empty()) {
// First expansion is empty, but we need to recursively expand.
res.push_back(VARIABLE_EXPAND_EMPTY);
}
}
for (size_t j = 0; j < var_item_list.size(); j++) {
const wcstring &next = var_item_list.at(j);
if (is_ok) {
if (j != 0) res.append(L" ");
res.append(next);
}
}
assert(stop_pos <= insize);
res.append(instr, stop_pos, insize - stop_pos);
is_ok &= expand_variables(res, out, i, errors);
} else {
for (size_t j = 0; j < var_item_list.size(); j++) {
const wcstring &next = var_item_list.at(j);
if (is_ok && i == 0 && stop_pos == insize) {
append_completion(out, next);
} else {
if (is_ok) {
wcstring new_in;
new_in.append(instr, 0, i);
if (i > 0) {
if (instr.at(i - 1) != VARIABLE_EXPAND) {
new_in.push_back(INTERNAL_SEPARATOR);
} else if (next.empty()) {
new_in.push_back(VARIABLE_EXPAND_EMPTY);
}
}
assert(stop_pos <= insize);
new_in.append(next);
new_in.append(instr, stop_pos, insize - stop_pos);
is_ok &= expand_variables(new_in, out, i, errors);
}
}
}
}
return is_ok;
}
// Even with no value, we still need to parse out slice syntax. Behave as though we
// had 1 value, so $foo[1] always works.
const size_t slice_start = stop_pos;
if (slice_start < insize && instr.at(slice_start) == L'[') {
const wchar_t *in = instr.c_str();
wchar_t *slice_end;
size_t bad_pos;
bad_pos = parse_slice(in + slice_start, &slice_end, var_idx_list, var_pos_list, 1);
if (bad_pos != 0) {
append_syntax_error(errors, stop_pos + bad_pos, L"Invalid index value");
is_ok = 0;
return is_ok;
}
stop_pos = (slice_end - in);
// Validate that the parsed indexes are valid.
for (size_t j = 0; j < var_idx_list.size(); j++) {
long tmp = var_idx_list.at(j);
if (tmp != 1) {
size_t var_src_pos = var_pos_list.at(j);
append_syntax_error(errors, slice_start + var_src_pos, ARRAY_BOUNDS_ERR);
is_ok = 0;
return is_ok;
}
}
}
// Expand a non-existing variable.
if (c == VARIABLE_EXPAND) {
// Regular expansion, i.e. expand this argument to nothing.
empty = true;
} else {
// Expansion to single argument.
wcstring res;
res.append(instr, 0, i);
if (i > 0 && instr.at(i - 1) == VARIABLE_EXPAND_SINGLE) {
res.push_back(VARIABLE_EXPAND_EMPTY);
}
assert(stop_pos <= insize);
res.append(instr, stop_pos, insize - stop_pos);
is_ok &= expand_variables(res, out, i, errors);
return is_ok;
}
}
if (!empty) {
append_completion(out, instr);
}
return is_ok;
}
/// Perform bracket expansion.
static expand_error_t expand_brackets(const wcstring &instr, expand_flags_t flags,
std::vector<completion_t> *out, parse_error_list_t *errors) {
bool syntax_error = false;
int bracket_count = 0;
const wchar_t *bracket_begin = NULL, *bracket_end = NULL;
const wchar_t *last_sep = NULL;
const wchar_t *item_begin;
size_t length_preceding_brackets, length_following_brackets, tot_len;
const wchar_t *const in = instr.c_str();
// Locate the first non-nested bracket pair.
for (const wchar_t *pos = in; (*pos) && !syntax_error; pos++) {
switch (*pos) {
case BRACKET_BEGIN: {
if (bracket_count == 0) bracket_begin = pos;
bracket_count++;
break;
}
case BRACKET_END: {
bracket_count--;
if (bracket_count < 0) {
syntax_error = true;
} else if (bracket_count == 0) {
bracket_end = pos;
break;
}
}
case BRACKET_SEP: {
if (bracket_count == 1) last_sep = pos;
break;
}
default: {
break; // we ignore all other characters here
}
}
}
if (bracket_count > 0) {
if (!(flags & EXPAND_FOR_COMPLETIONS)) {
syntax_error = true;
} else {
// The user hasn't typed an end bracket yet; make one up and append it, then expand
// that.
wcstring mod;
if (last_sep) {
mod.append(in, bracket_begin - in + 1);
mod.append(last_sep + 1);
mod.push_back(BRACKET_END);
} else {
mod.append(in);
mod.push_back(BRACKET_END);
}
// Note: this code looks very fishy, apparently it has never worked.
return expand_brackets(mod, 1, out, errors);
}
}
if (syntax_error) {
append_syntax_error(errors, SOURCE_LOCATION_UNKNOWN, _(L"Mismatched brackets"));
return EXPAND_ERROR;
}
if (bracket_begin == NULL) {
append_completion(out, instr);
return EXPAND_OK;
}
length_preceding_brackets = (bracket_begin - in);
length_following_brackets = wcslen(bracket_end) - 1;
tot_len = length_preceding_brackets + length_following_brackets;
item_begin = bracket_begin + 1;
for (const wchar_t *pos = (bracket_begin + 1); true; pos++) {
if (bracket_count == 0 && ((*pos == BRACKET_SEP) || (pos == bracket_end))) {
assert(pos >= item_begin);
size_t item_len = pos - item_begin;
wcstring whole_item;
whole_item.reserve(tot_len + item_len + 2);
whole_item.append(in, length_preceding_brackets);
whole_item.append(item_begin, item_len);
whole_item.append(bracket_end + 1);
expand_brackets(whole_item, flags, out, errors);
item_begin = pos + 1;
if (pos == bracket_end) break;
}
if (*pos == BRACKET_BEGIN) {
bracket_count++;
}
if (*pos == BRACKET_END) {
bracket_count--;
}
}
return EXPAND_OK;
}
/// Perform cmdsubst expansion.
static int expand_cmdsubst(const wcstring &input, std::vector<completion_t> *out_list,
parse_error_list_t *errors) {
wchar_t *paran_begin = 0, *paran_end = 0;
std::vector<wcstring> sub_res;
size_t i, j;
wchar_t *tail_begin = 0;
const wchar_t *const in = input.c_str();
int parse_ret;
switch (parse_ret = parse_util_locate_cmdsubst(in, &paran_begin, &paran_end, false)) {
case -1: {
append_syntax_error(errors, SOURCE_LOCATION_UNKNOWN, L"Mismatched parenthesis");
return 0;
}
case 0: {
append_completion(out_list, input);
return 1;
}
case 1: {
break;
}
default: {
DIE("unhandled parse_ret value");
break;
}
}
const wcstring subcmd(paran_begin + 1, paran_end - paran_begin - 1);
if (exec_subshell(subcmd, sub_res, true /* do apply exit status */) == -1) {
append_cmdsub_error(errors, SOURCE_LOCATION_UNKNOWN,
L"Unknown error while evaulating command substitution");
return 0;
}
tail_begin = paran_end + 1;
if (*tail_begin == L'[') {
std::vector<long> slice_idx;
std::vector<size_t> slice_source_positions;
const wchar_t *const slice_begin = tail_begin;
wchar_t *slice_end;
size_t bad_pos;
bad_pos =
parse_slice(slice_begin, &slice_end, slice_idx, slice_source_positions, sub_res.size());
if (bad_pos != 0) {
append_syntax_error(errors, slice_begin - in + bad_pos, L"Invalid index value");
return 0;
}
wcstring_list_t sub_res2;
tail_begin = slice_end;
for (i = 0; i < slice_idx.size(); i++) {
long idx = slice_idx.at(i);
if (idx < 1 || (size_t)idx > sub_res.size()) {
size_t pos = slice_source_positions.at(i);
append_syntax_error(errors, slice_begin - in + pos, ARRAY_BOUNDS_ERR);
return 0;
}
idx = idx - 1;
sub_res2.push_back(sub_res.at(idx));
// debug( 0, L"Pushing item '%ls' with index %d onto sliced result", al_get(
// sub_res, idx ), idx );
// sub_res[idx] = 0; // ??
}
sub_res = sub_res2;
}
// Recursively call ourselves to expand any remaining command substitutions. The result of this
// recursive call using the tail of the string is inserted into the tail_expand array list
std::vector<completion_t> tail_expand;
expand_cmdsubst(tail_begin, &tail_expand, errors); // TODO: offset error locations
// Combine the result of the current command substitution with the result of the recursive tail
// expansion.
for (i = 0; i < sub_res.size(); i++) {
const wcstring &sub_item = sub_res.at(i);
const wcstring sub_item2 = escape_string(sub_item, 1);
wcstring whole_item;
for (j = 0; j < tail_expand.size(); j++) {
whole_item.clear();
const wcstring &tail_item = tail_expand.at(j).completion;
// sb_append_substring( &whole_item, in, len1 );
whole_item.append(in, paran_begin - in);
// sb_append_char( &whole_item, INTERNAL_SEPARATOR );
whole_item.push_back(INTERNAL_SEPARATOR);
// sb_append_substring( &whole_item, sub_item2, item_len );
whole_item.append(sub_item2);
// sb_append_char( &whole_item, INTERNAL_SEPARATOR );
whole_item.push_back(INTERNAL_SEPARATOR);
// sb_append( &whole_item, tail_item );
whole_item.append(tail_item);
// al_push( out, whole_item.buff );
append_completion(out_list, whole_item);
}
}
return 1;
}
// Given that input[0] is HOME_DIRECTORY or tilde (ugh), return the user's name. Return the empty
// string if it is just a tilde. Also return by reference the index of the first character of the
// remaining part of the string (e.g. the subsequent slash).
static wcstring get_home_directory_name(const wcstring &input, size_t *out_tail_idx) {
const wchar_t *const in = input.c_str();
assert(in[0] == HOME_DIRECTORY || in[0] == L'~');
size_t tail_idx;
const wchar_t *name_end = wcschr(in, L'/');
if (name_end) {
tail_idx = name_end - in;
} else {
tail_idx = wcslen(in);
}
*out_tail_idx = tail_idx;
return input.substr(1, tail_idx - 1);
}
/// Attempts tilde expansion of the string specified, modifying it in place.
static void expand_home_directory(wcstring &input) {
if (!input.empty() && input.at(0) == HOME_DIRECTORY) {
size_t tail_idx;
wcstring username = get_home_directory_name(input, &tail_idx);
bool tilde_error = false;
wcstring home;
if (username.empty()) {
// Current users home directory.
home = env_get_string(L"HOME");
tail_idx = 1;
} else {
// Some other users home directory.
std::string name_cstr = wcs2string(username);
struct passwd *userinfo = getpwnam(name_cstr.c_str());
if (userinfo == NULL) {
tilde_error = true;
} else {
home = str2wcstring(userinfo->pw_dir);
}
}
wchar_t *realhome = wrealpath(home, NULL);
if (!tilde_error && realhome) {
input.replace(input.begin(), input.begin() + tail_idx, realhome);
} else {
input[0] = L'~';
}
free((void *)realhome);
}
}
void expand_tilde(wcstring &input) {
// Avoid needless COW behavior by ensuring we use const at.
const wcstring &tmp = input;
if (!tmp.empty() && tmp.at(0) == L'~') {
input.at(0) = HOME_DIRECTORY;
expand_home_directory(input);
}
}
static void unexpand_tildes(const wcstring &input, std::vector<completion_t> *completions) {
// If input begins with tilde, then try to replace the corresponding string in each completion
// with the tilde. If it does not, there's nothing to do.
if (input.empty() || input.at(0) != L'~') return;
// We only operate on completions that replace their contents. If we don't have any, we're done.
// In particular, empty vectors are common.
bool has_candidate_completion = false;
for (size_t i = 0; i < completions->size(); i++) {
if (completions->at(i).flags & COMPLETE_REPLACES_TOKEN) {
has_candidate_completion = true;
break;
}
}
if (!has_candidate_completion) return;
size_t tail_idx;
wcstring username_with_tilde = L"~";
username_with_tilde.append(get_home_directory_name(input, &tail_idx));
// Expand username_with_tilde.
wcstring home = username_with_tilde;
expand_tilde(home);
// Now for each completion that starts with home, replace it with the username_with_tilde.
for (size_t i = 0; i < completions->size(); i++) {
completion_t &comp = completions->at(i);
if ((comp.flags & COMPLETE_REPLACES_TOKEN) &&
string_prefixes_string(home, comp.completion)) {
comp.completion.replace(0, home.size(), username_with_tilde);
// And mark that our tilde is literal, so it doesn't try to escape it.
comp.flags |= COMPLETE_DONT_ESCAPE_TILDES;
}
}
}
// If the given path contains the user's home directory, replace that with a tilde. We don't try to
// be smart about case insensitivity, etc.
wcstring replace_home_directory_with_tilde(const wcstring &str) {
// Only absolute paths get this treatment.
wcstring result = str;
if (string_prefixes_string(L"/", result)) {
wcstring home_directory = L"~";
expand_tilde(home_directory);
if (!string_suffixes_string(L"/", home_directory)) {
home_directory.push_back(L'/');
}
// Now check if the home_directory prefixes the string.
if (string_prefixes_string(home_directory, result)) {
// Success
result.replace(0, home_directory.size(), L"~/");
}
}
return result;
}
/// Remove any internal separators. Also optionally convert wildcard characters to regular
/// equivalents. This is done to support EXPAND_SKIP_WILDCARDS.
static void remove_internal_separator(wcstring *str, bool conv) {
// Remove all instances of INTERNAL_SEPARATOR.
str->erase(std::remove(str->begin(), str->end(), (wchar_t)INTERNAL_SEPARATOR), str->end());
// If conv is true, replace all instances of ANY_CHAR with '?', ANY_STRING with '*',
// ANY_STRING_RECURSIVE with '*'.
if (conv) {
for (size_t idx = 0; idx < str->size(); idx++) {
switch (str->at(idx)) {
case ANY_CHAR: {
str->at(idx) = L'?';
break;
}
case ANY_STRING:
case ANY_STRING_RECURSIVE: {
str->at(idx) = L'*';
break;
}
default: {
break; // we ignore all other characters
}
}
}
}
}
/// A stage in string expansion is represented as a function that takes an input and returns a list
/// of output (by reference). We get flags and errors. It may return an error; if so expansion
/// halts.
typedef expand_error_t (*expand_stage_t)(const wcstring &input, //!OCLINT(unused param)
std::vector<completion_t> *out, //!OCLINT(unused param)
expand_flags_t flags, //!OCLINT(unused param)
parse_error_list_t *errors); //!OCLINT(unused param)
static expand_error_t expand_stage_cmdsubst(const wcstring &input, std::vector<completion_t> *out,
expand_flags_t flags, parse_error_list_t *errors) {
expand_error_t result = EXPAND_OK;
if (EXPAND_SKIP_CMDSUBST & flags) {
wchar_t *begin, *end;
if (parse_util_locate_cmdsubst(input.c_str(), &begin, &end, true) == 0) {
append_completion(out, input);
} else {
append_cmdsub_error(errors, SOURCE_LOCATION_UNKNOWN,
L"Command substitutions not allowed");
result = EXPAND_ERROR;
}
} else {
int cmdsubst_ok = expand_cmdsubst(input, out, errors);
if (!cmdsubst_ok) {
result = EXPAND_ERROR;
}
}
return result;
}
static expand_error_t expand_stage_variables(const wcstring &input, std::vector<completion_t> *out,
expand_flags_t flags, parse_error_list_t *errors) {
// We accept incomplete strings here, since complete uses expand_string to expand incomplete
// strings from the commandline.
wcstring next;
unescape_string(input, &next, UNESCAPE_SPECIAL | UNESCAPE_INCOMPLETE);
if (EXPAND_SKIP_VARIABLES & flags) {
for (size_t i = 0; i < next.size(); i++) {
if (next.at(i) == VARIABLE_EXPAND) {
next[i] = L'$';
}
}
append_completion(out, next);
} else {
if (!expand_variables(next, out, next.size(), errors)) {
return EXPAND_ERROR;
}
}
return EXPAND_OK;
}
static expand_error_t expand_stage_brackets(const wcstring &input, std::vector<completion_t> *out,
expand_flags_t flags, parse_error_list_t *errors) {
return expand_brackets(input, flags, out, errors);
}
static expand_error_t expand_stage_home_and_pid(const wcstring &input,
std::vector<completion_t> *out,
expand_flags_t flags, parse_error_list_t *errors) {
wcstring next = input;
if (!(EXPAND_SKIP_HOME_DIRECTORIES & flags)) {
expand_home_directory(next);
}
if (flags & EXPAND_FOR_COMPLETIONS) {
if (!next.empty() && next.at(0) == PROCESS_EXPAND) {
expand_pid(next, flags, out, NULL);
return EXPAND_OK;
}
append_completion(out, next);
} else if (!expand_pid(next, flags, out, errors)) {
return EXPAND_ERROR;
}
return EXPAND_OK;
}
static expand_error_t expand_stage_wildcards(const wcstring &input, std::vector<completion_t> *out,
expand_flags_t flags, parse_error_list_t *errors) {
UNUSED(errors);
expand_error_t result = EXPAND_OK;
wcstring path_to_expand = input;
remove_internal_separator(&path_to_expand, flags & EXPAND_SKIP_WILDCARDS);
const bool has_wildcard = wildcard_has(path_to_expand, true /* internal, i.e. ANY_CHAR */);
if (has_wildcard && (flags & EXECUTABLES_ONLY)) {
; // don't do wildcard expansion for executables, see issue #785
} else if (((flags & EXPAND_FOR_COMPLETIONS) && (!(flags & EXPAND_SKIP_WILDCARDS))) ||
has_wildcard) {
// We either have a wildcard, or we don't have a wildcard but we're doing completion
// expansion (so we want to get the completion of a file path). Note that if
// EXPAND_SKIP_WILDCARDS is set, we stomped wildcards in remove_internal_separator above, so
// there actually aren't any.
//
// So we're going to treat this input as a file path. Compute the "working directories",
// which may be CDPATH if the special flag is set.
const wcstring working_dir = env_get_pwd_slash();
wcstring_list_t effective_working_dirs;
bool for_cd = static_cast<bool>(flags & EXPAND_SPECIAL_FOR_CD);
bool for_command = static_cast<bool>(flags & EXPAND_SPECIAL_FOR_COMMAND);
if (!for_cd && !for_command) {
// Common case.
effective_working_dirs.push_back(working_dir);
} else {
// Either EXPAND_SPECIAL_FOR_COMMAND or EXPAND_SPECIAL_FOR_CD. We can handle these
// mostly the same. There's the following differences:
//
// 1. An empty CDPATH should be treated as '.', but an empty PATH should be left empty
// (no commands can be found).
//
// 2. PATH is only "one level," while CDPATH is multiple levels. That is, input like
// 'foo/bar' should resolve against CDPATH, but not PATH.
//
// In either case, we ignore the path if we start with ./ or /. Also ignore it if we are
// doing command completion and we contain a slash, per IEEE 1003.1, chapter 8 under
// PATH.
if (string_prefixes_string(L"/", path_to_expand) ||
string_prefixes_string(L"./", path_to_expand) ||
string_prefixes_string(L"../", path_to_expand) ||
(for_command && path_to_expand.find(L'/') != wcstring::npos)) {
effective_working_dirs.push_back(working_dir);
} else {
// Get the PATH/CDPATH and cwd. Perhaps these should be passed in. An empty CDPATH
// implies just the current directory, while an empty PATH is left empty.
env_var_t paths = env_get_string(for_cd ? L"CDPATH" : L"PATH");
if (paths.missing_or_empty()) paths = for_cd ? L"." : L"";
// Tokenize it into directories.
wcstokenizer tokenizer(paths, ARRAY_SEP_STR);
wcstring next_path;
while (tokenizer.next(next_path)) {
// Ensure that we use the working directory for relative cdpaths like ".".
effective_working_dirs.push_back(
path_apply_working_directory(next_path, working_dir));
}
}
}
result = EXPAND_WILDCARD_NO_MATCH;
std::vector<completion_t> expanded;
for (size_t wd_idx = 0; wd_idx < effective_working_dirs.size(); wd_idx++) {
int local_wc_res = wildcard_expand_string(
path_to_expand, effective_working_dirs.at(wd_idx), flags, &expanded);
if (local_wc_res > 0) {
// Something matched,so overall we matched.
result = EXPAND_WILDCARD_MATCH;
} else if (local_wc_res < 0) {
// Cancellation
result = EXPAND_ERROR;
break;
}
}
std::sort(expanded.begin(), expanded.end(), completion_t::is_naturally_less_than);
out->insert(out->end(), expanded.begin(), expanded.end());
} else {
// Can't fully justify this check. I think it's that SKIP_WILDCARDS is used when completing
// to mean don't do file expansions, so if we're not doing file expansions, just drop this
// completion on the floor.
if (!(flags & EXPAND_FOR_COMPLETIONS)) {
append_completion(out, path_to_expand);
}
}
return result;
}
expand_error_t expand_string(const wcstring &input, std::vector<completion_t> *out_completions,
expand_flags_t flags, parse_error_list_t *errors) {
// Early out. If we're not completing, and there's no magic in the input, we're done.
if (!(flags & EXPAND_FOR_COMPLETIONS) && expand_is_clean(input)) {
append_completion(out_completions, input);
return EXPAND_OK;
}
// Our expansion stages.
const expand_stage_t stages[] = {expand_stage_cmdsubst, expand_stage_variables,
expand_stage_brackets, expand_stage_home_and_pid,
expand_stage_wildcards};
// Load up our single initial completion.
std::vector<completion_t> completions, output_storage;
append_completion(&completions, input);
expand_error_t total_result = EXPAND_OK;
for (size_t stage_idx = 0;
total_result != EXPAND_ERROR && stage_idx < sizeof stages / sizeof *stages; stage_idx++) {
for (size_t i = 0; total_result != EXPAND_ERROR && i < completions.size(); i++) {
const wcstring &next = completions.at(i).completion;
expand_error_t this_result = stages[stage_idx](next, &output_storage, flags, errors);
// If this_result was no match, but total_result is that we have a match, then don't
// change it.
if (!(this_result == EXPAND_WILDCARD_NO_MATCH &&
total_result == EXPAND_WILDCARD_MATCH)) {
total_result = this_result;
}
}
// Output becomes our next stage's input.
completions.swap(output_storage);
output_storage.clear();
}
if (total_result != EXPAND_ERROR) {
// Hack to un-expand tildes (see #647).
if (!(flags & EXPAND_SKIP_HOME_DIRECTORIES)) {
unexpand_tildes(input, &completions);
}
out_completions->insert(out_completions->end(), completions.begin(), completions.end());
}
return total_result;
}
bool expand_one(wcstring &string, expand_flags_t flags, parse_error_list_t *errors) {
std::vector<completion_t> completions;
if (!(flags & EXPAND_FOR_COMPLETIONS) && expand_is_clean(string)) {
return true;
}
if (expand_string(string, &completions, flags | EXPAND_NO_DESCRIPTIONS, errors) &&
completions.size() == 1) {
string = completions.at(0).completion;
return true;
}
return false;
}
// https://github.com/fish-shell/fish-shell/issues/367
//
// With them the Seed of Wisdom did I sow,
// And with my own hand labour'd it to grow:
// And this was all the Harvest that I reap'd---
// "I came like Water, and like Wind I go."
static std::string escape_single_quoted_hack_hack_hack_hack(const char *str) {
std::string result;
size_t len = strlen(str);
result.reserve(len + 2);
result.push_back('\'');
for (size_t i = 0; i < len; i++) {
char c = str[i];
// Escape backslashes and single quotes only.
if (c == '\\' || c == '\'') result.push_back('\\');
result.push_back(c);
}
result.push_back('\'');
return result;
}
bool fish_xdm_login_hack_hack_hack_hack(std::vector<std::string> *cmds, int argc,
const char *const *argv) {
if (!cmds || cmds->size() != 1) {
return false;
}
bool result = false;
const std::string &cmd = cmds->at(0);
if (cmd == "exec \"${@}\"" || cmd == "exec \"$@\"") {
// We're going to construct a new command that starts with exec, and then has the
// remaining arguments escaped.
std::string new_cmd = "exec";
for (int i = 1; i < argc; i++) {
const char *arg = argv[i];
if (arg) {
new_cmd.push_back(' ');
new_cmd.append(escape_single_quoted_hack_hack_hack_hack(arg));
}
}
cmds->at(0) = new_cmd;
result = true;
}
return result;
}
bool expand_abbreviation(const wcstring &src, wcstring *output) {
if (src.empty()) return false;
// Get the abbreviations. Return false if we have none.
env_var_t var = env_get_string(USER_ABBREVIATIONS_VARIABLE_NAME);
if (var.missing_or_empty()) return false;
bool result = false;
wcstring line;
wcstokenizer tokenizer(var, ARRAY_SEP_STR);
while (tokenizer.next(line)) {
// Line is expected to be of the form 'foo=bar' or 'foo bar'. Parse out the first = or
// space. Silently skip on failure (no equals, or equals at the end or beginning). Try to
// avoid copying any strings until we are sure this is a match.
size_t equals_pos = line.find(L'=');
size_t space_pos = line.find(L' ');
size_t separator = mini(equals_pos, space_pos);
if (separator == wcstring::npos || separator == 0 || separator + 1 == line.size()) continue;
// Find the character just past the end of the command. Walk backwards, skipping spaces.
size_t cmd_end = separator;
while (cmd_end > 0 && iswspace(line.at(cmd_end - 1))) cmd_end--;
// See if this command matches.
if (line.compare(0, cmd_end, src) == 0) {
// Success. Set output to everything past the end of the string.
if (output != NULL) output->assign(line, separator + 1, wcstring::npos);
result = true;
break;
}
}
return result;
}