void CommandInsert(const char *table,
const BTkey& key,
int value)
{
int i;
if ((i = GetTable(table)) == NOT_FOUND) {
cerr << "Table not open!\n";
return;
}
Record* rec = new_in(db, Record);
rec->value = value;
GiST *gist = tables[i].gist;
gist->Insert(BTentry(key, (GiSTpage)rec));
cout << "(" << key << ", " << value << ") inserted into " << table << ".\n";
}
void CommandCreate(const char *method,
const char *table)
{
if (numTables == MAX_TABLES) {
cout << "This progam can only handle "<<MAX_TABLES<<" open tables.\n";
return;
}
if (GetTable(table) != NOT_FOUND) {
cerr << "Table already open!\n";
return;
}
if (strcmp(method, "btree")) {
cerr << "The only supported method is btree.\n";
return;
}
GiST *gist = new BT(db);
GiST_POST_Root* root = (GiST_POST_Root*)db.get_root_object();
if (root == NULL) {
root = new_in(db, GiST_POST_Root)(db);
db.set_root_object(root);
}
gist->Create(table);
if (!gist->IsOpen()) {
cout << "Error opening table.\n";
delete gist;
return;
}
cout << "Table " << table << " created as type " << method << ".\n";
tables[numTables].name = strdup(table);
tables[numTables].gist = gist;
numTables++;
}
/// 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 bool expand_variables(const wcstring &instr, std::vector<completion_t> *out, size_t 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 <= insize && "Invalid last_idx");
if (last_idx == 0) {
append_completion(out, instr);
return true;
}
// Locate the last VARIABLE_EXPAND or VARIABLE_EXPAND_SINGLE
bool is_single = false;
size_t varexp_char_idx = last_idx;
while (varexp_char_idx--) {
const wchar_t c = instr.at(varexp_char_idx);
if (c == VARIABLE_EXPAND || c == VARIABLE_EXPAND_SINGLE) {
is_single = (c == VARIABLE_EXPAND_SINGLE);
break;
}
}
if (varexp_char_idx >= instr.size()) {
// No variable expand char, we're done.
append_completion(out, instr);
return true;
}
// Get the variable name.
const size_t var_name_start = varexp_char_idx + 1;
size_t var_name_stop = var_name_start;
while (var_name_stop < insize) {
const wchar_t nc = instr.at(var_name_stop);
if (nc == VARIABLE_EXPAND_EMPTY) {
var_name_stop++;
break;
}
if (!valid_var_name_char(nc)) break;
var_name_stop++;
}
assert(var_name_stop >= var_name_start && "Bogus variable name indexes");
const size_t var_name_len = var_name_stop - var_name_start;
// It's an error if the name is empty.
if (var_name_len == 0) {
if (errors) {
parse_util_expand_variable_error(instr, 0 /* global_token_pos */, varexp_char_idx,
errors);
}
return false;
}
// Get the variable name as a string, then try to get the variable from env.
const wcstring var_name(instr, var_name_start, var_name_len);
// Do a dirty hack to make sliced history fast (#4650). We expand from either a variable, or a
// history_t. Note that "history" is read only in env.cpp so it's safe to special-case it in
// this way (it cannot be shadowed, etc).
history_t *history = nullptr;
maybe_t<env_var_t> var{};
if (var_name == L"history") {
// We do this only on the main thread, matching env.cpp.
if (is_main_thread()) {
history = reader_get_history();
}
} else if (var_name != wcstring{VARIABLE_EXPAND_EMPTY}) {
var = env_get(var_name);
}
// Parse out any following slice.
// Record the end of the variable name and any following slice.
size_t var_name_and_slice_stop = var_name_stop;
bool all_values = true;
const size_t slice_start = var_name_stop;
// List of indexes, and parallel array of source positions of each index in the variable list.
std::vector<long> var_idx_list;
std::vector<size_t> var_pos_list;
if (slice_start < insize && instr.at(slice_start) == L'[') {
all_values = false;
const wchar_t *in = instr.c_str();
wchar_t *slice_end;
// If a variable is missing, behave as though we have one value, so that $var[1] always
// works.
size_t effective_val_count = 1;
if (var) {
effective_val_count = var->as_list().size();
} else if (history) {
effective_val_count = history->size();
}
size_t bad_pos = parse_slice(in + slice_start, &slice_end, var_idx_list, var_pos_list,
effective_val_count);
if (bad_pos != 0) {
append_syntax_error(errors, slice_start + bad_pos, L"Invalid index value");
return false;
}
var_name_and_slice_stop = (slice_end - in);
}
if (!var && !history) {
// Expanding a non-existent variable.
if (!is_single) {
// Normal expansions of missing variables successfully expand to nothing.
return true;
} else {
// Expansion to single argument.
// Replace the variable name and slice with VARIABLE_EXPAND_EMPTY.
wcstring res(instr, 0, varexp_char_idx);
if (!res.empty() && res.back() == VARIABLE_EXPAND_SINGLE) {
res.push_back(VARIABLE_EXPAND_EMPTY);
}
res.append(instr, var_name_and_slice_stop, wcstring::npos);
return expand_variables(res, out, varexp_char_idx, errors);
}
}
// Ok, we have a variable or a history. Let's expand it.
// Start by respecting the sliced elements.
assert((var || history) && "Should have variable or history here");
wcstring_list_t var_item_list;
if (all_values) {
if (history) {
history->get_history(var_item_list);
} else {
var->to_list(var_item_list);
}
} else {
// We have to respect the slice.
if (history) {
// Ask history to map indexes to item strings.
// Note this may have missing entries for out-of-bounds.
auto item_map = history->items_at_indexes(var_idx_list);
for (long item_index : var_idx_list) {
auto iter = item_map.find(item_index);
if (iter != item_map.end()) {
var_item_list.push_back(iter->second);
}
}
} else {
const wcstring_list_t &all_var_items = var->as_list();
for (long item_index : var_idx_list) {
// Check that we are within array bounds. If not, skip the element. Note:
// Negative indices (`echo $foo[-1]`) are already converted to positive ones
// here, So tmp < 1 means it's definitely not in.
// Note we are 1-based.
if (item_index >= 1 && size_t(item_index) <= all_var_items.size()) {
var_item_list.push_back(all_var_items.at(item_index - 1));
}
}
}
}
if (is_single) {
wcstring res(instr, 0, varexp_char_idx);
if (!res.empty()) {
if (res.back() != 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);
}
}
// Append all entries in var_item_list, separated by spaces.
// Remove the last space.
if (!var_item_list.empty()) {
for (const wcstring &item : var_item_list) {
res.append(item);
res.push_back(L' ');
}
res.pop_back();
}
res.append(instr, var_name_and_slice_stop, wcstring::npos);
return expand_variables(res, out, varexp_char_idx, errors);
} else {
// Normal cartesian-product expansion.
for (const wcstring &item : var_item_list) {
if (varexp_char_idx == 0 && var_name_and_slice_stop == insize) {
append_completion(out, item);
} else {
wcstring new_in(instr, 0, varexp_char_idx);
if (!new_in.empty()) {
if (new_in.back() != VARIABLE_EXPAND) {
new_in.push_back(INTERNAL_SEPARATOR);
} else if (item.empty()) {
new_in.push_back(VARIABLE_EXPAND_EMPTY);
}
}
new_in.append(item);
new_in.append(instr, var_name_and_slice_stop, wcstring::npos);
if (!expand_variables(new_in, out, varexp_char_idx, errors)) {
return false;
}
}
}
}
return true;
}
