Files
pymol-open-source/layer2/CifFile.cpp
2024-05-20 09:07:33 -04:00

425 lines
9.9 KiB
C++

/*
* CIF tokenizer
*
* All keys are canonicalized to lowercase
*
* (c) 2014 Schrodinger, Inc.
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <cassert>
#include <iostream>
#include <string>
#include <vector>
#include "CifFile.h"
#include "File.h"
#include "MemoryDebug.h"
#include "strcasecmp.h"
namespace pymol {
namespace _cif_detail {
template <> const char* raw_to_typed(const char* s) { return s; }
template <> std::string raw_to_typed(const char* s) { return s; }
template <> char raw_to_typed(const char* s) { return s[0]; }
template <> int raw_to_typed(const char* s) { return atoi(s); }
/**
* Convert to floating point number, ignores uncertainty notation
* 1.23(45)e2 -> 1.23e2
*/
template <> double raw_to_typed(const char* s)
{
const char *close, *open = strchr(s, '(');
if (open && (close = strchr(open, ')'))) {
return atof(std::string(s, open - s).append(close + 1).c_str());
}
return atof(s);
}
template <> float raw_to_typed(const char* s)
{
return static_cast<float>(raw_to_typed<double>(s));
}
} // namespace _cif_detail
// basic IO and string handling
// Return true if "c" is whitespace or null
static bool iswhitespace0(char c) {
return strchr(" \t\r\n", c) ? true : false;
}
// Return true if "c" is whitespace
static bool iswhitespace(char c) {
return (c && iswhitespace0(c));
}
// Return true if "c" is line feed or carriage return
static bool islinefeed(char c) {
return (c == '\r' || c == '\n');
}
// Return true if "c" is line feed or carriage return or null
static bool islinefeed0(char c) {
return (!c || islinefeed(c));
}
// Return true if "c" is double or single quote
static bool isquote(char c) {
return (c == '"' || c == '\'');
}
// FreeBSD name conflict
#ifdef isspecial
#undef isspecial
#endif
// Return true if token is a STAR keyword
static bool isspecial(const char *token) {
return (token[0] == '_'
|| strncasecmp("data_", token, 5) == 0
|| strncasecmp("save_", token, 5) == 0
|| strcasecmp("loop_", token) == 0
|| strcasecmp("stop_", token) == 0
|| strcasecmp("global_", token) == 0);
}
// convert all chars to lowercase
static void tolowerinplace(char *p) {
for (; *p; p++) {
if (*p <= 'Z' && *p >= 'A')
*p -= 'Z' - 'z';
}
}
// CIF stuff
static const cif_array EMPTY_ARRAY(nullptr);
/*
* Class to store CIF loops. Only for parsing, do not use in any higher level
* reading functions.
*/
class cif_loop {
public:
int ncols;
int nrows;
const char **values;
// methods
const char * get_value_raw(int row, int col) const;
};
// get table value, return nullptr if indices out of bounds
const char * cif_loop::get_value_raw(int row, int col) const {
if (row >= nrows)
return nullptr;
return values[row * ncols + col];
}
// get the number of elements in this array
unsigned cif_array::size() const {
return (col == NOT_IN_LOOP) ? 1 : pointer.loop->nrows;
}
/// Get array value, return nullptr if `pos >= size()` or value in ['.', '?']
const char* cif_array::get_value_raw(unsigned pos) const
{
if (col == NOT_IN_LOOP)
return (pos > 0) ? nullptr : pointer.value;
return pointer.loop->get_value_raw(pos, col);
}
// true if all values in ['.', '?']
bool cif_array::is_missing_all() const {
for (unsigned i = 0, n = size(); i != n; ++i) {
if (!is_missing(i))
return false;
}
return true;
}
/**
* Get a pointer to array or nullptr if not found
*
* Can lookup different aliases, the first one found is returned.
* Also supports an alias shortcut for the trivial case where mmCIF uses
* a colon and CIF uses an underscore: `get_arr("_foo?bar")` is identical to
* `get_arr("_foo.bar", "_foo_bar")`
*
* @param key data name, must be lower case
*/
const cif_array * cif_data::get_arr(const char * key) const {
const char* p = strchr(key, '?');
decltype(m_dict)::const_iterator it;
#ifndef NDEBUG
for (const char* q = key; *q; ++q) {
assert("key must be lower case" && !('Z' >= *q && *q >= 'A'));
}
#endif
// support alias shortcut: '?' matches '.' and '_'
if (p != nullptr) {
std::string tmp(key);
// replace '?' by '.' or '_'
tmp[p - key] = '.';
if ((it = m_dict.find(tmp.c_str())) != m_dict.end())
return &it->second;
tmp[p - key] = '_';
if ((it = m_dict.find(tmp.c_str())) != m_dict.end())
return &it->second;
} else {
if ((it = m_dict.find(key)) != m_dict.end())
return &it->second;
}
return nullptr;
}
const cif_array* cif_data::empty_array() {
return &EMPTY_ARRAY;
}
const cif_data* cif_data::get_saveframe(const char* code) const {
auto it = m_saveframes.find(code);
if (it != m_saveframes.end())
return &it->second;
return nullptr;
}
bool cif_file::parse_file(const char* filename) {
char* contents = FileGetContents(filename, nullptr);
if (!contents) {
error(std::string("failed to read file ").append(filename).c_str());
return false;
}
return parse(std::move(contents));
}
bool cif_file::parse_string(const char* contents) {
return parse(std::move(mstrdup(contents)));
}
void cif_file::error(const char* msg) {
std::cout << "ERROR " << msg << std::endl;
}
// constructor
cif_file::cif_file(const char* filename, const char* contents_) {
if (contents_) {
parse_string(contents_);
} else if (filename) {
parse_file(filename);
}
}
// constructor
cif_file::cif_file() = default;
cif_file::cif_file(cif_file&&) = default;
// move assignment
cif_file& cif_file::operator=(cif_file&&) = default;
// destructor
cif_file::~cif_file() = default;
bool cif_file::parse(char*&& p) {
m_datablocks.clear();
m_tokens.clear();
m_contents.reset(p);
if (!p) {
error("parse(nullptr)");
return false;
}
auto& tokens = m_tokens;
char quote;
char prev = '\0';
std::vector<bool> keypossible;
// tokenize
while (true) {
while (iswhitespace(*p))
prev = *(p++);
if (!*p)
break;
if (*p == '#') {
while (!(islinefeed0(*++p)));
prev = *p;
} else if (isquote(*p)) { // will nullptr the closing quote
quote = *p;
keypossible.push_back(false);
tokens.push_back(p + 1);
while (*++p && !(*p == quote && iswhitespace0(p[1])));
if (*p)
*(p++) = 0;
prev = *p;
} else if (*p == ';' && islinefeed(prev)) {
// multi-line tokens start with ";" and end with "\n;"
// multi-line tokens cannot be keys, only values.
keypossible.push_back(false);
tokens.push_back(p + 1);
// advance until `\n;`
while (*++p && !(islinefeed(*p) && p[1] == ';'));
// step to next line and null the line feed
if (*p) {
*p = 0;
// \r\n on Windows)
if (p - 1 > tokens.back() && *(p - 1) == '\r') {
*(p - 1) = 0;
}
p += 2;
}
prev = ';';
} else { // will null the whitespace
char * q = p++;
while (!iswhitespace0(*p)) ++p;
prev = *p;
if (p - q == 1 && (*q == '?' || *q == '.')) {
// store values '.' (inapplicable) and '?' (unknown) as null-pointers
q = nullptr;
keypossible.push_back(false);
} else {
if (*p)
*(p++) = 0;
keypossible.push_back(true);
}
tokens.push_back(q);
}
}
cif_data* current_frame = nullptr;
std::vector<cif_data*> frame_stack;
std::unique_ptr<cif_data> global_block;
decltype(m_datablocks) datablocksnew;
// parse into dictionary
for (unsigned int i = 0, n = tokens.size(); i < n; i++) {
if (!keypossible[i]) {
error("expected key (1)");
return false;
} else if (tokens[i][0] == '_') {
if (!current_frame) {
error("missing data_ (unexpected data name)");
return false;
}
if (i + 1 == n) {
error("truncated");
return false;
}
tolowerinplace(tokens[i]);
current_frame->m_dict[tokens[i]].set_value(tokens[i + 1]);
i++;
} else if (strcasecmp("loop_", tokens[i]) == 0) {
if (!current_frame) {
error("missing data_ (unexpected loop)");
return false;
}
int ncols = 0;
int nrows = 0;
cif_loop *loop = nullptr;
// loop data
loop = new cif_loop;
current_frame->m_loops.emplace_back(loop);
// columns
while (++i < n && keypossible[i] && tokens[i][0] == '_') {
tolowerinplace(tokens[i]);
current_frame->m_dict[tokens[i]].set_loop(loop, ncols);
ncols++;
}
if (loop) {
// loop data
loop->values = (const char **) &tokens[i];
loop->ncols = ncols;
}
// rows
while (i < n && !(keypossible[i] && isspecial(tokens[i]))) {
i += ncols;
if (i > n) {
error("truncated loop");
return false;
}
nrows++;
}
// loop data
if (loop) {
loop->nrows = nrows;
}
i--;
} else if (strncasecmp("data_", tokens[i], 5) == 0) {
datablocksnew.emplace_back();
current_frame = &datablocksnew.back();
current_frame->m_code = tokens[i] + 5;
frame_stack = {current_frame};
} else if (strncasecmp("global_", tokens[i], 5) == 0) {
// STAR feature, not supported in CIF
current_frame = new cif_data;
global_block.reset(current_frame);
frame_stack = {current_frame};
} else if (strncasecmp("save_", tokens[i], 5) == 0) {
if (tokens[i][5]) {
// begin
if (!current_frame) {
error("top-level save_");
return false;
}
const char * key(tokens[i] + 5);
current_frame = &current_frame->m_saveframes[key];
frame_stack.push_back(current_frame);
} else {
// end
if (frame_stack.size() < 2) {
error("unexpected save_");
return false;
}
frame_stack.pop_back();
current_frame = frame_stack.back();
}
} else {
error("expected key (2)");
return false;
}
}
m_datablocks = std::move(datablocksnew);
return true;
}
} // namespace pymol
// vi:sw=2:ts=2