in fdbserver/sqlite/sqlite3.amalgamation.c [101196:101411]
static void porter_stemmer(const char *zIn, int nIn, char *zOut, int *pnOut){
int i, j;
char zReverse[28];
char *z, *z2;
if( nIn<3 || nIn>=(int)sizeof(zReverse)-7 ){
/* The word is too big or too small for the porter stemmer.
** Fallback to the copy stemmer */
copy_stemmer(zIn, nIn, zOut, pnOut);
return;
}
for(i=0, j=sizeof(zReverse)-6; i<nIn; i++, j--){
char c = zIn[i];
if( c>='A' && c<='Z' ){
zReverse[j] = c + 'a' - 'A';
}else if( c>='a' && c<='z' ){
zReverse[j] = c;
}else{
/* The use of a character not in [a-zA-Z] means that we fallback
** to the copy stemmer */
copy_stemmer(zIn, nIn, zOut, pnOut);
return;
}
}
memset(&zReverse[sizeof(zReverse)-5], 0, 5);
z = &zReverse[j+1];
/* Step 1a */
if( z[0]=='s' ){
if(
!stem(&z, "sess", "ss", 0) &&
!stem(&z, "sei", "i", 0) &&
!stem(&z, "ss", "ss", 0)
){
z++;
}
}
/* Step 1b */
z2 = z;
if( stem(&z, "dee", "ee", m_gt_0) ){
/* Do nothing. The work was all in the test */
}else if(
(stem(&z, "gni", "", hasVowel) || stem(&z, "de", "", hasVowel))
&& z!=z2
){
if( stem(&z, "ta", "ate", 0) ||
stem(&z, "lb", "ble", 0) ||
stem(&z, "zi", "ize", 0) ){
/* Do nothing. The work was all in the test */
}else if( doubleConsonant(z) && (*z!='l' && *z!='s' && *z!='z') ){
z++;
}else if( m_eq_1(z) && star_oh(z) ){
*(--z) = 'e';
}
}
/* Step 1c */
if( z[0]=='y' && hasVowel(z+1) ){
z[0] = 'i';
}
/* Step 2 */
switch( z[1] ){
case 'a':
stem(&z, "lanoita", "ate", m_gt_0) ||
stem(&z, "lanoit", "tion", m_gt_0);
break;
case 'c':
stem(&z, "icne", "ence", m_gt_0) ||
stem(&z, "icna", "ance", m_gt_0);
break;
case 'e':
stem(&z, "rezi", "ize", m_gt_0);
break;
case 'g':
stem(&z, "igol", "log", m_gt_0);
break;
case 'l':
stem(&z, "ilb", "ble", m_gt_0) ||
stem(&z, "illa", "al", m_gt_0) ||
stem(&z, "iltne", "ent", m_gt_0) ||
stem(&z, "ile", "e", m_gt_0) ||
stem(&z, "ilsuo", "ous", m_gt_0);
break;
case 'o':
stem(&z, "noitazi", "ize", m_gt_0) ||
stem(&z, "noita", "ate", m_gt_0) ||
stem(&z, "rota", "ate", m_gt_0);
break;
case 's':
stem(&z, "msila", "al", m_gt_0) ||
stem(&z, "ssenevi", "ive", m_gt_0) ||
stem(&z, "ssenluf", "ful", m_gt_0) ||
stem(&z, "ssensuo", "ous", m_gt_0);
break;
case 't':
stem(&z, "itila", "al", m_gt_0) ||
stem(&z, "itivi", "ive", m_gt_0) ||
stem(&z, "itilib", "ble", m_gt_0);
break;
}
/* Step 3 */
switch( z[0] ){
case 'e':
stem(&z, "etaci", "ic", m_gt_0) ||
stem(&z, "evita", "", m_gt_0) ||
stem(&z, "ezila", "al", m_gt_0);
break;
case 'i':
stem(&z, "itici", "ic", m_gt_0);
break;
case 'l':
stem(&z, "laci", "ic", m_gt_0) ||
stem(&z, "luf", "", m_gt_0);
break;
case 's':
stem(&z, "ssen", "", m_gt_0);
break;
}
/* Step 4 */
switch( z[1] ){
case 'a':
if( z[0]=='l' && m_gt_1(z+2) ){
z += 2;
}
break;
case 'c':
if( z[0]=='e' && z[2]=='n' && (z[3]=='a' || z[3]=='e') && m_gt_1(z+4) ){
z += 4;
}
break;
case 'e':
if( z[0]=='r' && m_gt_1(z+2) ){
z += 2;
}
break;
case 'i':
if( z[0]=='c' && m_gt_1(z+2) ){
z += 2;
}
break;
case 'l':
if( z[0]=='e' && z[2]=='b' && (z[3]=='a' || z[3]=='i') && m_gt_1(z+4) ){
z += 4;
}
break;
case 'n':
if( z[0]=='t' ){
if( z[2]=='a' ){
if( m_gt_1(z+3) ){
z += 3;
}
}else if( z[2]=='e' ){
stem(&z, "tneme", "", m_gt_1) ||
stem(&z, "tnem", "", m_gt_1) ||
stem(&z, "tne", "", m_gt_1);
}
}
break;
case 'o':
if( z[0]=='u' ){
if( m_gt_1(z+2) ){
z += 2;
}
}else if( z[3]=='s' || z[3]=='t' ){
stem(&z, "noi", "", m_gt_1);
}
break;
case 's':
if( z[0]=='m' && z[2]=='i' && m_gt_1(z+3) ){
z += 3;
}
break;
case 't':
stem(&z, "eta", "", m_gt_1) ||
stem(&z, "iti", "", m_gt_1);
break;
case 'u':
if( z[0]=='s' && z[2]=='o' && m_gt_1(z+3) ){
z += 3;
}
break;
case 'v':
case 'z':
if( z[0]=='e' && z[2]=='i' && m_gt_1(z+3) ){
z += 3;
}
break;
}
/* Step 5a */
if( z[0]=='e' ){
if( m_gt_1(z+1) ){
z++;
}else if( m_eq_1(z+1) && !star_oh(z+1) ){
z++;
}
}
/* Step 5b */
if( m_gt_1(z) && z[0]=='l' && z[1]=='l' ){
z++;
}
/* z[] is now the stemmed word in reverse order. Flip it back
** around into forward order and return.
*/
*pnOut = i = (int)strlen(z);
zOut[i] = 0;
while( *z ){
zOut[--i] = *(z++);
}
}