kshell.cpp
/*
This file is part of the KDE libraries
Copyright (c) 2003 Oswald Buddenhagen <ossi@kde.org>
This library is free software; you can redistribute it and/or
modify it under the terms of the GNU Library General Public
License as published by the Free Software Foundation; either
version 2 of the License, or (at your option) any later version.
This library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Library General Public License for more details.
You should have received a copy of the GNU Library General Public License
along with this library; see the file COPYING.LIB. If not, write to
the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
Boston, MA 02110-1301, USA.
*/
#include <kshell.h>
#include <qfile.h>
#include <stdlib.h>
#include <pwd.h>
#include <sys/types.h>
static int fromHex( QChar c )
{
if (c >= '0' && c <= '9')
return c - '0';
else if (c >= 'A' && c <= 'F')
return c - 'A' + 10;
else if (c >= 'a' && c <= 'f')
return c - 'a' + 10;
return -1;
}
inline static bool isQuoteMeta( uint c )
{
#if 0 // it's not worth it, especially after seeing gcc's asm output ...
static const uchar iqm[] = {
0x00, 0x00, 0x00, 0x00, 0x94, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x10, 0x00, 0x00, 0x00, 0x00
}; // \'"$
return (c < sizeof(iqm) * 8) && (iqm[c / 8] & (1 << (c & 7)));
#else
return c == '\\' || c == '\'' || c == '"' || c == '$';
#endif
}
inline static bool isMeta( uint c )
{
static const uchar iqm[] = {
0x00, 0x00, 0x00, 0x00, 0xdc, 0x07, 0x00, 0xd8,
0x00, 0x00, 0x00, 0x10, 0x01, 0x00, 0x00, 0x38
}; // \'"$`<>|;&(){}*?#
return (c < sizeof(iqm) * 8) && (iqm[c / 8] & (1 << (c & 7)));
}
QStringList KShell::splitArgs( const QString &args, int flags, int *err )
{
QStringList ret;
bool firstword = flags & AbortOnMeta;
for (uint pos = 0; ; ) {
QChar c;
do {
if (pos >= args.length())
goto okret;
c = args.unicode()[pos++];
} while (c.isSpace());
QString cret;
if ((flags & TildeExpand) && c == '~') {
uint opos = pos;
for (; ; pos++) {
if (pos >= args.length())
break;
c = args.unicode()[pos];
if (c == '/' || c.isSpace())
break;
if (isQuoteMeta( c )) {
pos = opos;
c = '~';
goto notilde;
}
if ((flags & AbortOnMeta) && isMeta( c ))
goto metaerr;
}
QString ccret = homeDir( QConstString( args.unicode() + opos, pos - opos ).string() );
if (ccret.isEmpty()) {
pos = opos;
c = '~';
goto notilde;
}
if (pos >= args.length()) {
ret += ccret;
goto okret;
}
pos++;
if (c.isSpace()) {
ret += ccret;
firstword = false;
continue;
}
cret = ccret;
}
// before the notilde label, as a tilde does not match anyway
if (firstword) {
if (c == '_' || (c >= 'A' && c <= 'Z') || (c >= 'a' && c <= 'z')) {
uint pos2 = pos;
QChar cc;
do
cc = args[pos2++];
while (cc == '_' || (cc >= 'A' && cc <= 'Z') ||
(cc >= 'a' && cc <= 'z') || (cc >= '0' && cc <= '9'));
if (cc == '=')
goto metaerr;
}
}
notilde:
do {
if (c == '\'') {
uint spos = pos;
do {
if (pos >= args.length())
goto quoteerr;
c = args.unicode()[pos++];
} while (c != '\'');
cret += QConstString( args.unicode() + spos, pos - spos - 1 ).string();
} else if (c == '"') {
for (;;) {
if (pos >= args.length())
goto quoteerr;
c = args.unicode()[pos++];
if (c == '"')
break;
if (c == '\\') {
if (pos >= args.length())
goto quoteerr;
c = args.unicode()[pos++];
if (c != '"' && c != '\\' &&
!((flags & AbortOnMeta) && (c == '$' || c == '`')))
cret += '\\';
} else if ((flags & AbortOnMeta) && (c == '$' || c == '`'))
goto metaerr;
cret += c;
}
} else if (c == '$' && args[pos] == '\'') {
pos++;
for (;;) {
if (pos >= args.length())
goto quoteerr;
c = args.unicode()[pos++];
if (c == '\'')
break;
if (c == '\\') {
if (pos >= args.length())
goto quoteerr;
c = args.unicode()[pos++];
switch (c) {
case 'a': cret += '\a'; break;
case 'b': cret += '\b'; break;
case 'e': cret += '\033'; break;
case 'f': cret += '\f'; break;
case 'n': cret += '\n'; break;
case 'r': cret += '\r'; break;
case 't': cret += '\t'; break;
case '\\': cret += '\\'; break;
case '\'': cret += '\''; break;
case 'c': cret += args[pos++] & 31; break;
case 'x':
{
int hv = fromHex( args[pos] );
if (hv < 0) {
cret += "\\x";
} else {
int hhv = fromHex( args[++pos] );
if (hhv > 0) {
hv = hv * 16 + hhv;
pos++;
}
cret += QChar( hv );
}
break;
}
default:
if (c >= '0' && c <= '7') {
int hv = c - '0';
for (int i = 0; i < 2; i++) {
c = args[pos];
if (c < '0' || c > '7')
break;
hv = hv * 8 + (c - '0');
pos++;
}
cret += QChar( hv );
} else {
cret += '\\';
cret += c;
}
break;
}
} else
cret += c;
}
} else {
if (c == '\\') {
if (pos >= args.length())
goto quoteerr;
c = args.unicode()[pos++];
if (!c.isSpace() &&
!((flags & AbortOnMeta) ? isMeta( c ) : isQuoteMeta( c )))
cret += '\\';
} else if ((flags & AbortOnMeta) && isMeta( c ))
goto metaerr;
cret += c;
}
if (pos >= args.length())
break;
c = args.unicode()[pos++];
} while (!c.isSpace());
ret += cret;
firstword = false;
}
okret:
if (err)
*err = NoError;
return ret;
quoteerr:
if (err)
*err = BadQuoting;
return QStringList();
metaerr:
if (err)
*err = FoundMeta;
return QStringList();
}
inline static bool isSpecial( uint c )
{
static const uchar iqm[] = {
0xff, 0xff, 0xff, 0xff, 0xdd, 0x07, 0x00, 0xd8,
0x00, 0x00, 0x00, 0x10, 0x01, 0x00, 0x00, 0x38
}; // 0-32 \'"$`<>|;&(){}*?#
return (c < sizeof(iqm) * 8) && (iqm[c / 8] & (1 << (c & 7)));
}
QString KShell::joinArgs( const QStringList &args )
{
QChar q( '\'' );
QString ret;
for (QStringList::ConstIterator it = args.begin(); it != args.end(); ++it) {
if (!ret.isEmpty())
ret += ' ';
if (!(*it).length())
ret.append( q ).append( q );
else {
for (uint i = 0; i < (*it).length(); i++)
if (isSpecial((*it).unicode()[i])) {
QString tmp(*it);
tmp.replace( q, "'\\''" );
ret += q;
tmp += q;
ret += tmp;
goto ex;
}
ret += *it;
ex: ;
}
}
return ret;
}
QString KShell::joinArgs( const char * const *args, int nargs )
{
if (!args)
return QString::null; // well, QString::empty, in fact. qt sucks ;)
QChar q( '\'' );
QString ret;
for (const char * const *argp = args; nargs && *argp; argp++, nargs--) {
if (!ret.isEmpty())
ret += ' ';
if (!**argp)
ret.append( q ).append( q );
else {
QString tmp( QFile::decodeName( *argp ) );
for (uint i = 0; i < tmp.length(); i++)
if (isSpecial(tmp.unicode()[i])) {
tmp.replace( q, "'\\''" );
ret += q;
tmp += q;
ret += tmp;
goto ex;
}
ret += tmp;
ex: ;
}
}
return ret;
}
QString KShell::joinArgsDQ( const QStringList &args )
{
QChar q( '\'' ), sp( ' ' ), bs( '\\' );
QString ret;
for (QStringList::ConstIterator it = args.begin(); it != args.end(); ++it) {
if (!ret.isEmpty())
ret += sp;
if (!(*it).length())
ret.append( q ).append( q );
else {
for (uint i = 0; i < (*it).length(); i++)
if (isSpecial((*it).unicode()[i])) {
ret.append( '$' ).append( q );
for (uint pos = 0; pos < (*it).length(); pos++) {
int c = (*it).unicode()[pos];
if (c < 32) {
ret += bs;
switch (c) {
case '\a': ret += 'a'; break;
case '\b': ret += 'b'; break;
case '\033': ret += 'e'; break;
case '\f': ret += 'f'; break;
case '\n': ret += 'n'; break;
case '\r': ret += 'r'; break;
case '\t': ret += 't'; break;
case '\034': ret += 'c'; ret += '|'; break;
default: ret += 'c'; ret += c + '@'; break;
}
} else {
if (c == '\'' || c == '\\')
ret += bs;
ret += c;
}
}
ret.append( q );
goto ex;
}
ret += *it;
ex: ;
}
}
return ret;
}
QString KShell::tildeExpand( const QString &fname )
{
if (fname[0] == '~') {
int pos = fname.find( '/' );
if (pos < 0)
return homeDir( QConstString( fname.unicode() + 1, fname.length() - 1 ).string() );
QString ret = homeDir( QConstString( fname.unicode() + 1, pos - 1 ).string() );
if (!ret.isNull())
ret += QConstString( fname.unicode() + pos, fname.length() - pos ).string();
return ret;
}
return fname;
}
QString KShell::homeDir( const QString &user )
{
if (user.isEmpty())
return QFile::decodeName( getenv( "HOME" ) );
struct passwd *pw = getpwnam( QFile::encodeName( user ).data() );
if (!pw)
return QString::null;
return QFile::decodeName( pw->pw_dir );
}
KShell::TildeExpand
Perform tilde expansion.
Definition: kshell.h:46
KShell::FoundMeta
The AbortOnMeta flag was set and a shell meta character was encoutered.
Definition: kshell.h:79
KShell::homeDir
QString homeDir(const QString &user)
Obtain a user's home directory.
Definition: kshell.cpp:369
KShell::joinArgsDQ
QString joinArgsDQ(const QStringList &args)
Same as above, but $'' is used instead of '' for the quoting.
Definition: kshell.cpp:311
KShell::BadQuoting
Indicates a parsing error, like an unterminated quoted string.
Definition: kshell.h:73
KShell::NoError
Success.
Definition: kshell.h:68
KShell::tildeExpand
QString tildeExpand(const QString &path)
Performs tilde expansion on path.
Definition: kshell.cpp:355
KShell::joinArgs
QString joinArgs(const QStringList &args)
Quotes and joins args together according to POSIX shell rules.
Definition: kshell.cpp:257
KShell::AbortOnMeta
Bail out if a non-quoting and not quoted shell meta character is encoutered.
Definition: kshell.h:58
KShell::splitArgs
QStringList splitArgs(const QString &cmd, int flags=0, int *err=0)
Splits cmd according to POSIX shell word splitting and quoting rules.
Definition: kshell.cpp:65

KDE Home | KDE Accessibility Home | Description of Access Keys