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#include "cpp11/list.hpp"
#include "cpp11/sexp.hpp"
#include "cpp11/strings.hpp"
#include "connection.h"
#include "grisu3.h"
#include <array>
#include <fstream>
#include <sstream>
enum quote_escape_t { DOUBLE = 1, BACKSLASH = 2, NONE = 3 };
void stream_delim(
const cpp11::sexp& connection,
const cpp11::sexp& x,
int i,
char delim,
const std::string& na,
quote_escape_t escape);
void stream_delim_row(
const cpp11::sexp& connection,
const cpp11::list& x,
int i,
char delim,
const std::string& na,
quote_escape_t escape,
const char* eol) {
int p = Rf_length(x);
for (int j = 0; j < p - 1; ++j) {
stream_delim(connection, x.at(j), i, delim, na, escape);
write_bytes(connection, &delim, 1);
}
stream_delim(connection, x.at(p - 1), i, delim, na, escape);
write_bytes(connection, eol, strlen(eol));
}
bool needs_quote(const char* string, char delim, const std::string& na) {
if (string == na) {
return true;
}
for (const char* cur = string; *cur != '\0'; ++cur) {
if (*cur == '\n' || *cur == '\r' || *cur == '"' || *cur == delim) {
return true;
}
}
return false;
}
void stream_delim(
const cpp11::sexp& connection,
const char* string,
char delim,
const std::string& na,
quote_escape_t escape) {
bool quotes = needs_quote(string, delim, na);
if (quotes) {
write_bytes(connection, "\"", 1);
}
for (const char* cur = string; *cur != '\0'; ++cur) {
switch (*cur) {
case '"':
switch (escape) {
case DOUBLE:
write_bytes(connection, "\"\"", 2);
break;
case BACKSLASH:
write_bytes(connection, "\\\"", 2);
break;
case NONE:
write_bytes(connection, "\"", 1);
break;
}
break;
default:
write_bytes(connection, cur, 1);
}
}
if (quotes) {
write_bytes(connection, "\"", 1);
}
}
void validate_col_type(SEXP x, const std::string& name) {
switch (TYPEOF(x)) {
case LGLSXP:
case INTSXP:
case REALSXP:
case STRSXP:
break;
default:
cpp11::stop(
"Don't know how to handle vector of type %s in column '%s'.",
Rf_type2char(TYPEOF(x)),
name.c_str());
}
}
void stream_delim(
const cpp11::sexp& connection,
const cpp11::list& df,
char delim,
const std::string& na,
bool col_names,
bool bom,
quote_escape_t escape,
const char* eol) {
int p = Rf_length(df);
if (p == 0) {
return;
}
if (bom) {
write_bytes(connection, "\xEF\xBB\xBF", 3);
}
cpp11::strings names(df.attr("names"));
// Validate column types
for (int j = 0; j < p; ++j) {
validate_col_type(df.at(j), names[j]);
}
if (col_names) {
cpp11::strings names(df.attr("names"));
for (int j = 0; j < p; ++j) {
stream_delim(connection, names, j, delim, na, escape);
if (j != p - 1) {
write_bytes(connection, &delim, 1);
}
}
write_bytes(connection, eol, strlen(eol));
}
cpp11::sexp first_col = df[0];
int n = Rf_length(first_col);
for (int i = 0; i < n; ++i) {
stream_delim_row(connection, df, i, delim, na, escape, eol);
}
}
[[cpp11::register]] void stream_delim_(
const cpp11::list& df,
const cpp11::sexp& connection,
char delim,
const std::string& na,
bool col_names,
bool bom,
int quote_escape,
const char* eol) {
stream_delim(
connection,
df,
delim,
na,
col_names,
bom,
static_cast<quote_escape_t>(quote_escape),
eol);
}
// =============================================================================
// Derived from EncodeElementS in RPostgreSQL
// Written by: tomoakin@kenroku.kanazawa-u.ac.jp
// License: GPL-2
void stream_delim(
const cpp11::sexp& connection,
const cpp11::sexp& x,
int i,
char delim,
const std::string& na,
quote_escape_t escape) {
switch (TYPEOF(x)) {
case LGLSXP: {
int value = LOGICAL(x)[i];
if (value == TRUE) {
write_bytes(connection, "TRUE", 4);
} else if (value == FALSE) {
write_bytes(connection, "FALSE", 5);
} else {
write_bytes(connection, na.c_str(), na.size());
}
break;
}
case INTSXP: {
int value = INTEGER(x)[i];
if (value == NA_INTEGER) {
write_bytes(connection, na.c_str(), na.size());
} else {
std::array<char, 32> str;
int len = snprintf(str.data(), 32, "%i", value);
if (len > 32) {
cpp11::stop("integer too big");
}
write_bytes(connection, str.data(), len);
}
break;
}
case REALSXP: {
double value = REAL(x)[i];
if (!R_FINITE(value)) {
if (ISNA(value) || ISNAN(value)) {
write_bytes(connection, na.c_str(), na.size());
} else if (value > 0) {
write_bytes(connection, "Inf", 3);
} else {
write_bytes(connection, "-Inf", 4);
}
} else {
std::array<char, 32> str;
int len = dtoa_grisu3(value, str.data());
write_bytes(connection, str.data(), len);
}
break;
}
case STRSXP: {
if (STRING_ELT(x, i) == NA_STRING) {
write_bytes(connection, na.c_str(), na.size());
} else {
stream_delim(
connection,
Rf_translateCharUTF8(STRING_ELT(x, i)),
delim,
na,
escape);
}
break;
}
default:
cpp11::stop(
"Don't know how to handle vector of type %s.", Rf_type2char(TYPEOF(x)));
}
}
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