sqlite/ext/misc/sqlite3_stdio.c
drh 863fcdc116 Be consistent about using "CRLF" instead of "CRNL".
FossilOrigin-Name: ec4f4cfd5f8ca83fad4f08cf6566251d9c63e50a3a4284baca299bd94b047951
2024-10-14 09:19:02 +00:00

276 lines
7.4 KiB
C

/*
** 2024-09-24
**
** The author disclaims copyright to this source code. In place of
** a legal notice, here is a blessing:
**
** May you do good and not evil.
** May you find forgiveness for yourself and forgive others.
** May you share freely, never taking more than you give.
**
*************************************************************************
**
** Implementation of standard I/O interfaces for UTF-8 that are missing
** on Windows.
*/
#ifdef _WIN32 /* This file is a no-op on all platforms except Windows */
#ifndef _SQLITE3_STDIO_H_
#include "sqlite3_stdio.h"
#endif
#undef WIN32_LEAN_AND_MEAN
#define WIN32_LEAN_AND_MEAN
#include <windows.h>
#include <stdlib.h>
#include <string.h>
#include <stdio.h>
#include <assert.h>
#include "sqlite3.h"
#include <ctype.h>
#include <stdarg.h>
#include <io.h>
#include <fcntl.h>
/*
** If the SQLITE_U8TEXT_ONLY option is defined, then use O_U8TEXT
** when appropriate on all output. (Sometimes use O_BINARY when
** rendering ASCII text in cases where NL-to-CRLF expansion would
** not be correct.)
**
** If the SQLITE_U8TEXT_STDIO option is defined, then use O_U8TEXT
** when appropriate when writing to stdout or stderr. Use O_BINARY
** or O_TEXT (depending on things like the .mode and the .crlf setting
** in the CLI, or other context clues in other applications) for all
** other output channels.
**
** The default behavior, if neither of the above is defined is to
** use O_U8TEXT when writing to the Windows console (or anything
** else for which _isatty() returns true) and to use O_BINARY or O_TEXT
** for all other output channels.
*/
#if defined(SQLITE_U8TEXT_ONLY)
# define UseWtextForOutput(fd) 1
# define UseWtextForInput(fd) 1
# define IsConsole(fd) _isatty(_fileno(fd))
#elif defined(SQLITE_U8TEXT_STDIO)
# define UseWtextForOutput(fd) ((fd)==stdout || (fd)==stderr)
# define UseWtextForInput(fd) ((fd)==stdin)
# define IsConsole(fd) _isatty(_fileno(fd))
#else
# define UseWtextForOutput(fd) _isatty(_fileno(fd))
# define UseWtextForInput(fd) _isatty(_fileno(fd))
# define IsConsole(fd) 1
#endif
/*
** Global variables determine if simulated O_BINARY mode is to be
** used for stdout or other, respectively. Simulated O_BINARY mode
** means the mode is usually O_BINARY, but switches to O_U8TEXT for
** unicode characters U+0080 or greater (any character that has a
** multi-byte representation in UTF-8). This is the only way we
** have found to render Unicode characters on a Windows console while
** at the same time avoiding undesirable \n to \r\n translation.
*/
static int simBinaryStdout = 0;
static int simBinaryOther = 0;
/*
** Determine if simulated binary mode should be used for output to fd
*/
static int UseBinaryWText(FILE *fd){
if( fd==stdout || fd==stderr ){
return simBinaryStdout;
}else{
return simBinaryOther;
}
}
/*
** Work-alike for the fopen() routine from the standard C library.
*/
FILE *sqlite3_fopen(const char *zFilename, const char *zMode){
FILE *fp = 0;
wchar_t *b1, *b2;
int sz1, sz2;
sz1 = (int)strlen(zFilename);
sz2 = (int)strlen(zMode);
b1 = malloc( (sz1+1)*sizeof(b1[0]) );
b2 = malloc( (sz2+1)*sizeof(b1[0]) );
if( b1 && b2 ){
sz1 = MultiByteToWideChar(CP_UTF8, 0, zFilename, sz1, b1, sz1);
b1[sz1] = 0;
sz2 = MultiByteToWideChar(CP_UTF8, 0, zMode, sz2, b2, sz2);
b2[sz2] = 0;
fp = _wfopen(b1, b2);
}
free(b1);
free(b2);
simBinaryOther = 0;
return fp;
}
/*
** Work-alike for the popen() routine from the standard C library.
*/
FILE *sqlite3_popen(const char *zCommand, const char *zMode){
FILE *fp = 0;
wchar_t *b1, *b2;
int sz1, sz2;
sz1 = (int)strlen(zCommand);
sz2 = (int)strlen(zMode);
b1 = malloc( (sz1+1)*sizeof(b1[0]) );
b2 = malloc( (sz2+1)*sizeof(b1[0]) );
if( b1 && b2 ){
sz1 = MultiByteToWideChar(CP_UTF8, 0, zCommand, sz1, b1, sz1);
b1[sz1] = 0;
sz2 = MultiByteToWideChar(CP_UTF8, 0, zMode, sz2, b2, sz2);
b2[sz2] = 0;
fp = _wpopen(b1, b2);
}
free(b1);
free(b2);
return fp;
}
/*
** Work-alike for fgets() from the standard C library.
*/
char *sqlite3_fgets(char *buf, int sz, FILE *in){
if( UseWtextForInput(in) ){
/* When reading from the command-prompt in Windows, it is necessary
** to use _O_WTEXT input mode to read UTF-16 characters, then translate
** that into UTF-8. Otherwise, non-ASCII characters all get translated
** into '?'.
*/
wchar_t *b1 = malloc( sz*sizeof(wchar_t) );
if( b1==0 ) return 0;
_setmode(_fileno(in), IsConsole(in) ? _O_WTEXT : _O_U8TEXT);
if( fgetws(b1, sz/4, in)==0 ){
sqlite3_free(b1);
return 0;
}
WideCharToMultiByte(CP_UTF8, 0, b1, -1, buf, sz, 0, 0);
sqlite3_free(b1);
return buf;
}else{
/* Reading from a file or other input source, just read bytes without
** any translation. */
return fgets(buf, sz, in);
}
}
/*
** Send ASCII text as O_BINARY. But for Unicode characters U+0080 and
** greater, switch to O_U8TEXT.
*/
static void piecemealOutput(wchar_t *b1, int sz, FILE *out){
int i;
wchar_t c;
while( sz>0 ){
for(i=0; i<sz && b1[i]>=0x80; i++){}
if( i>0 ){
c = b1[i];
b1[i] = 0;
fflush(out);
_setmode(_fileno(out), _O_U8TEXT);
fputws(b1, out);
fflush(out);
b1 += i;
b1[0] = c;
sz -= i;
}else{
fflush(out);
_setmode(_fileno(out), _O_TEXT);
_setmode(_fileno(out), _O_BINARY);
fwrite(&b1[0], 1, 1, out);
for(i=1; i<sz && b1[i]<0x80; i++){
fwrite(&b1[i], 1, 1, out);
}
fflush(out);
_setmode(_fileno(out), _O_U8TEXT);
b1 += i;
sz -= i;
}
}
}
/*
** Work-alike for fputs() from the standard C library.
*/
int sqlite3_fputs(const char *z, FILE *out){
if( !UseWtextForOutput(out) ){
/* Writing to a file or other destination, just write bytes without
** any translation. */
return fputs(z, out);
}else{
/* When writing to the command-prompt in Windows, it is necessary
** to use O_U8TEXT to render Unicode U+0080 and greater. Go ahead
** use O_U8TEXT for everything in text mode.
*/
int sz = (int)strlen(z);
wchar_t *b1 = malloc( (sz+1)*sizeof(wchar_t) );
if( b1==0 ) return 0;
sz = MultiByteToWideChar(CP_UTF8, 0, z, sz, b1, sz);
b1[sz] = 0;
_setmode(_fileno(out), _O_U8TEXT);
if( UseBinaryWText(out) ){
piecemealOutput(b1, sz, out);
}else{
fputws(b1, out);
}
sqlite3_free(b1);
return 0;
}
}
/*
** Work-alike for fprintf() from the standard C library.
*/
int sqlite3_fprintf(FILE *out, const char *zFormat, ...){
int rc;
if( UseWtextForOutput(out) ){
/* When writing to the command-prompt in Windows, it is necessary
** to use _O_WTEXT input mode and write UTF-16 characters.
*/
char *z;
va_list ap;
va_start(ap, zFormat);
z = sqlite3_vmprintf(zFormat, ap);
va_end(ap);
sqlite3_fputs(z, out);
rc = (int)strlen(z);
sqlite3_free(z);
}else{
/* Writing to a file or other destination, just write bytes without
** any translation. */
va_list ap;
va_start(ap, zFormat);
rc = vfprintf(out, zFormat, ap);
va_end(ap);
}
return rc;
}
/*
** Set the mode for an output stream. mode argument is typically _O_BINARY or
** _O_TEXT.
*/
void sqlite3_fsetmode(FILE *fp, int mode){
if( !UseWtextForOutput(fp) ){
fflush(fp);
_setmode(_fileno(fp), mode);
}else if( fp==stdout || fp==stderr ){
simBinaryStdout = (mode==_O_BINARY);
}else{
simBinaryOther = (mode==_O_BINARY);
}
}
#endif /* defined(_WIN32) */