/*
** Compile and run this standalone program in order to generate code that
** implements a function that will translate alphabetic identifiers into
** parser token codes.
*/
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
/*
** A header comment placed at the beginning of generated code.
*/
static const char zHdr[] =
"/***** This file contains automatically generated code ******\n"
"**\n"
"** The code in this file has been automatically generated by\n"
"**\n"
"** $Header: /home/drh/sqlite/trans/cvs/sqlite/sqlite/tool/mkkeywordhash.c,v 1.26 2007/03/27 14:44:52 drh Exp $\n"
"**\n"
"** The code in this file implements a function that determines whether\n"
"** or not a given identifier is really an SQL keyword. The same thing\n"
"** might be implemented more directly using a hand-written hash table.\n"
"** But by using this automatically generated code, the size of the code\n"
"** is substantially reduced. This is important for embedded applications\n"
"** on platforms with limited memory.\n"
"*/\n"
;
/*
** All the keywords of the SQL language are stored as in a hash
** table composed of instances of the following structure.
*/
typedef struct Keyword Keyword;
struct Keyword {
char *zName; /* The keyword name */
char *zTokenType; /* Token value for this keyword */
int mask; /* Code this keyword if non-zero */
int id; /* Unique ID for this record */
int hash; /* Hash on the keyword */
int offset; /* Offset to start of name string */
int len; /* Length of this keyword, not counting final \000 */
int prefix; /* Number of characters in prefix */
int iNext; /* Index in aKeywordTable[] of next with same hash */
int substrId; /* Id to another keyword this keyword is embedded in */
int substrOffset; /* Offset into substrId for start of this keyword */
};
/*
** Define masks used to determine which keywords are allowed
*/
#ifdef SQLITE_OMIT_ALTERTABLE
# define ALTER 0
#else
# define ALTER 0x00000001
#endif
#define ALWAYS 0x00000002
#ifdef SQLITE_OMIT_ANALYZE
# define ANALYZE 0
#else
# define ANALYZE 0x00000004
#endif
#ifdef SQLITE_OMIT_ATTACH
# define ATTACH 0
#else
# define ATTACH 0x00000008
#endif
#ifdef SQLITE_OMIT_AUTOINCREMENT
# define AUTOINCR 0
#else
# define AUTOINCR 0x00000010
#endif
#ifdef SQLITE_OMIT_CAST
# define CAST 0
#else
# define CAST 0x00000020
#endif
#ifdef SQLITE_OMIT_COMPOUND_SELECT
# define COMPOUND 0
#else
# define COMPOUND 0x00000040
#endif
#ifdef SQLITE_OMIT_CONFLICT_CLAUSE
# define CONFLICT 0
#else
# define CONFLICT 0x00000080
#endif
#ifdef SQLITE_OMIT_EXPLAIN
# define EXPLAIN 0
#else
# define EXPLAIN 0x00000100
#endif
#ifdef SQLITE_OMIT_FOREIGN_KEY
# define FKEY 0
#else
# define FKEY 0x00000200
#endif
#ifdef SQLITE_OMIT_PRAGMA
# define PRAGMA 0
#else
# define PRAGMA 0x00000400
#endif
#ifdef SQLITE_OMIT_REINDEX
# define REINDEX 0
#else
# define REINDEX 0x00000800
#endif
#ifdef SQLITE_OMIT_SUBQUERY
# define SUBQUERY 0
#else
# define SUBQUERY 0x00001000
#endif
#ifdef SQLITE_OMIT_TRIGGER
# define TRIGGER 0
#else
# define TRIGGER 0x00002000
#endif
#if defined(SQLITE_OMIT_VACUUM) || defined(SQLITE_OMIT_ATTACH)
# define VACUUM 0
#else
# define VACUUM 0x00004000
#endif
#ifdef SQLITE_OMIT_VIEW
# define VIEW 0
#else
# define VIEW 0x00008000
#endif
#ifdef SQLITE_OMIT_VIRTUALTABLE
# define VTAB 0
#else
# define VTAB 0x00010000
#endif
/*
** These are the keywords
*/
static Keyword aKeywordTable[] = {
{ "ABORT", "TK_ABORT", CONFLICT|TRIGGER },
{ "ADD", "TK_ADD", ALTER },
{ "AFTER", "TK_AFTER", TRIGGER },
{ "ALL", "TK_ALL", ALWAYS },
{ "ALTER", "TK_ALTER", ALTER },
{ "ANALYZE", "TK_ANALYZE", ANALYZE },
{ "AND", "TK_AND", ALWAYS },
{ "AS", "TK_AS", ALWAYS },
{ "ASC", "TK_ASC", ALWAYS },
{ "ATTACH", "TK_ATTACH", ATTACH },
{ "AUTOINCREMENT", "TK_AUTOINCR", AUTOINCR },
{ "BEFORE", "TK_BEFORE", TRIGGER },
{ "BEGIN", "TK_BEGIN", ALWAYS },
{ "BETWEEN", "TK_BETWEEN", ALWAYS },
{ "BY", "TK_BY", ALWAYS },
{ "CASCADE", "TK_CASCADE", FKEY },
{ "CASE", "TK_CASE", ALWAYS },
{ "CAST", "TK_CAST", CAST },
{ "CHECK", "TK_CHECK", ALWAYS },
{ "COLLATE", "TK_COLLATE", ALWAYS },
{ "COLUMN", "TK_COLUMNKW", ALTER },
{ "COMMIT", "TK_COMMIT", ALWAYS },
{ "CONFLICT", "TK_CONFLICT", CONFLICT },
{ "CONSTRAINT", "TK_CONSTRAINT", ALWAYS },
{ "CREATE", "TK_CREATE", ALWAYS },
{ "CROSS", "TK_JOIN_KW", ALWAYS },
{ "CURRENT_DATE", "TK_CTIME_KW", ALWAYS },
{ "CURRENT_TIME", "TK_CTIME_KW", ALWAYS },
{ "CURRENT_TIMESTAMP","TK_CTIME_KW", ALWAYS },
{ "DATABASE", "TK_DATABASE", ATTACH },
{ "DEFAULT", "TK_DEFAULT", ALWAYS },
{ "DEFERRED", "TK_DEFERRED", ALWAYS },
{ "DEFERRABLE", "TK_DEFERRABLE", FKEY },
{ "DELETE", "TK_DELETE", ALWAYS },
{ "DESC", "TK_DESC", ALWAYS },
{ "DETACH", "TK_DETACH", ATTACH },
{ "DISTINCT", "TK_DISTINCT", ALWAYS },
{ "DROP", "TK_DROP", ALWAYS },
{ "END", "TK_END", ALWAYS },
{ "EACH", "TK_EACH", TRIGGER },
{ "ELSE", "TK_ELSE", ALWAYS },
{ "ESCAPE", "TK_ESCAPE", ALWAYS },
{ "EXCEPT", "TK_EXCEPT", COMPOUND },
{ "EXCLUSIVE", "TK_EXCLUSIVE", ALWAYS },
{ "EXISTS", "TK_EXISTS", ALWAYS },
{ "EXPLAIN", "TK_EXPLAIN", EXPLAIN },
{ "FAIL", "TK_FAIL", CONFLICT|TRIGGER },
{ "FOR", "TK_FOR", TRIGGER },
{ "FOREIGN", "TK_FOREIGN", FKEY },
{ "FROM", "TK_FROM", ALWAYS },
{ "FULL", "TK_JOIN_KW", ALWAYS },
{ "GLOB", "TK_LIKE_KW", ALWAYS },
{ "GROUP", "TK_GROUP", ALWAYS },
{ "HAVING", "TK_HAVING", ALWAYS },
{ "IF", "TK_IF", ALWAYS },
{ "IGNORE", "TK_IGNORE", CONFLICT|TRIGGER },
{ "IMMEDIATE", "TK_IMMEDIATE", ALWAYS },
{ "IN", "TK_IN", ALWAYS },
{ "INDEX", "TK_INDEX", ALWAYS },
{ "INITIALLY", "TK_INITIALLY", FKEY },
{ "INNER", "TK_JOIN_KW", ALWAYS },
{ "INSERT", "TK_INSERT", ALWAYS },
{ "INSTEAD", "TK_INSTEAD", TRIGGER },
{ "INTERSECT", "TK_INTERSECT", COMPOUND },
{ "INTO", "TK_INTO", ALWAYS },
{ "IS", "TK_IS", ALWAYS },
{ "ISNULL", "TK_ISNULL", ALWAYS },
{ "JOIN", "TK_JOIN", ALWAYS },
{ "KEY", "TK_KEY", ALWAYS },
{ "LEFT", "TK_JOIN_KW", ALWAYS },
{ "LIKE", "TK_LIKE_KW", ALWAYS },
{ "LIMIT", "TK_LIMIT", ALWAYS },
{ "MATCH", "TK_MATCH", ALWAYS },
{ "NATURAL", "TK_JOIN_KW", ALWAYS },
{ "NOT", "TK_NOT", ALWAYS },
{ "NOTNULL", "TK_NOTNULL", ALWAYS },
{ "NULL", "TK_NULL", ALWAYS },
{ "OF", "TK_OF", ALWAYS },
{ "OFFSET", "TK_OFFSET", ALWAYS },
{ "ON", "TK_ON", ALWAYS },
{ "OR", "TK_OR", ALWAYS },
{ "ORDER", "TK_ORDER", ALWAYS },
{ "OUTER", "TK_JOIN_KW", ALWAYS },
{ "PLAN", "TK_PLAN", EXPLAIN },
{ "PRAGMA", "TK_PRAGMA", PRAGMA },
{ "PRIMARY", "TK_PRIMARY", ALWAYS },
{ "QUERY", "TK_QUERY", EXPLAIN },
{ "RAISE", "TK_RAISE", TRIGGER },
{ "REFERENCES", "TK_REFERENCES", FKEY },
{ "REGEXP", "TK_LIKE_KW", ALWAYS },
{ "REINDEX", "TK_REINDEX", REINDEX },
{ "RENAME", "TK_RENAME", ALTER },
{ "REPLACE", "TK_REPLACE", CONFLICT },
{ "RESTRICT", "TK_RESTRICT", FKEY },
{ "RIGHT", "TK_JOIN_KW", ALWAYS },
{ "ROLLBACK", "TK_ROLLBACK", ALWAYS },
{ "ROW", "TK_ROW", TRIGGER },
{ "SELECT", "TK_SELECT", ALWAYS },
{ "SET", "TK_SET", ALWAYS },
{ "STATEMENT", "TK_STATEMENT", TRIGGER },
{ "TABLE", "TK_TABLE", ALWAYS },
{ "TEMP", "TK_TEMP", ALWAYS },
{ "TEMPORARY", "TK_TEMP", ALWAYS },
{ "THEN", "TK_THEN", ALWAYS },
{ "TO", "TK_TO", ALTER },
{ "TRANSACTION", "TK_TRANSACTION", ALWAYS },
{ "TRIGGER", "TK_TRIGGER", TRIGGER },
{ "UNION", "TK_UNION", COMPOUND },
{ "UNIQUE", "TK_UNIQUE", ALWAYS },
{ "UPDATE", "TK_UPDATE", ALWAYS },
{ "USING", "TK_USING", ALWAYS },
{ "VACUUM", "TK_VACUUM", VACUUM },
{ "VALUES", "TK_VALUES", ALWAYS },
{ "VIEW", "TK_VIEW", VIEW },
{ "VIRTUAL", "TK_VIRTUAL", VTAB },
{ "WHEN", "TK_WHEN", ALWAYS },
{ "WHERE", "TK_WHERE", ALWAYS },
};
/* Number of keywords */
static int NKEYWORD = (sizeof(aKeywordTable)/sizeof(aKeywordTable[0]));
/* An array to map all upper-case characters into their corresponding
** lower-case character.
*/
const unsigned char sqlite3UpperToLower[] = {
0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17,
18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35,
36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53,
54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 97, 98, 99,100,101,102,103,
104,105,106,107,108,109,110,111,112,113,114,115,116,117,118,119,120,121,
122, 91, 92, 93, 94, 95, 96, 97, 98, 99,100,101,102,103,104,105,106,107,
108,109,110,111,112,113,114,115,116,117,118,119,120,121,122,123,124,125,
126,127,128,129,130,131,132,133,134,135,136,137,138,139,140,141,142,143,
144,145,146,147,148,149,150,151,152,153,154,155,156,157,158,159,160,161,
162,163,164,165,166,167,168,169,170,171,172,173,174,175,176,177,178,179,
180,181,182,183,184,185,186,187,188,189,190,191,192,193,194,195,196,197,
198,199,200,201,202,203,204,205,206,207,208,209,210,211,212,213,214,215,
216,217,218,219,220,221,222,223,224,225,226,227,228,229,230,231,232,233,
234,235,236,237,238,239,240,241,242,243,244,245,246,247,248,249,250,251,
252,253,254,255
};
#define UpperToLower sqlite3UpperToLower
/*
** Comparision function for two Keyword records
*/
static int keywordCompare1(const void *a, const void *b){
const Keyword *pA = (Keyword*)a;
const Keyword *pB = (Keyword*)b;
int n = pA->len - pB->len;
if( n==0 ){
n = strcmp(pA->zName, pB->zName);
}
return n;
}
static int keywordCompare2(const void *a, const void *b){
const Keyword *pA = (Keyword*)a;
const Keyword *pB = (Keyword*)b;
int n = strcmp(pA->zName, pB->zName);
return n;
}
static int keywordCompare3(const void *a, const void *b){
const Keyword *pA = (Keyword*)a;
const Keyword *pB = (Keyword*)b;
int n = pA->offset - pB->offset;
return n;
}
/*
** Return a KeywordTable entry with the given id
*/
static Keyword *findById(int id){
int i;
for(i=0; i<NKEYWORD; i++){
if( aKeywordTable[i].id==id ) break;
}
return &aKeywordTable[i];
}
/*
** This routine does the work. The generated code is printed on standard
** output.
*/
int main(int argc, char **argv){
int i, j, k, h;
int bestSize, bestCount;
int count;
int nChar;
int aHash[1000]; /* 1000 is much bigger than NKEYWORD */
/* Remove entries from the list of keywords that have mask==0 */
for(i=j=0; i<NKEYWORD; i++){
if( aKeywordTable[i].mask==0 ) continue;
if( j<i ){
aKeywordTable[j] = aKeywordTable[i];
}
j++;
}
NKEYWORD = j;
/* Fill in the lengths of strings and hashes for all entries. */
for(i=0; i<NKEYWORD; i++){
Keyword *p = &aKeywordTable[i];
p->len = strlen(p->zName);
p->hash = (UpperToLower[p->zName[0]]*4) ^
(UpperToLower[p->zName[p->len-1]]*3) ^ p->len;
p->id = i+1;
}
/* Sort the table from shortest to longest keyword */
qsort(aKeywordTable, NKEYWORD, sizeof(aKeywordTable[0]), keywordCompare1);
/* Look for short keywords embedded in longer keywords */
for(i=NKEYWORD-2; i>=0; i--){
Keyword *p = &aKeywordTable[i];
for(j=NKEYWORD-1; j>i && p->substrId==0; j--){
Keyword *pOther = &aKeywordTable[j];
if( pOther->substrId ) continue;
if( pOther->len<=p->len ) continue;
for(k=0; k<=pOther->len-p->len; k++){
if( memcmp(p->zName, &pOther->zName[k], p->len)==0 ){
p->substrId = pOther->id;
p->substrOffset = k;
break;
}
}
}
}
/* Sort the table into alphabetical order */
qsort(aKeywordTable, NKEYWORD, sizeof(aKeywordTable[0]), keywordCompare2);
/* Fill in the offset for all entries */
nChar = 0;
for(i=0; i<NKEYWORD; i++){
Keyword *p = &aKeywordTable[i];
if( p->offset>0 || p->substrId ) continue;
p->offset = nChar;
nChar += p->len;
for(k=p->len-1; k>=1; k--){
for(j=i+1; j<NKEYWORD; j++){
Keyword *pOther = &aKeywordTable[j];
if( pOther->offset>0 || pOther->substrId ) continue;
if( pOther->len<=k ) continue;
if( memcmp(&p->zName[p->len-k], pOther->zName, k)==0 ){
p = pOther;
p->offset = nChar - k;
nChar = p->offset + p->len;
p->zName += k;
p->len -= k;
p->prefix = k;
j = i;
k = p->len;
}
}
}
}
for(i=0; i<NKEYWORD; i++){
Keyword *p = &aKeywordTable[i];
if( p->substrId ){
p->offset = findById(p->substrId)->offset + p->substrOffset;
}
}
/* Sort the table by offset */
qsort(aKeywordTable, NKEYWORD, sizeof(aKeywordTable[0]), keywordCompare3);
/* Figure out how big to make the hash table in order to minimize the
** number of collisions */
bestSize = NKEYWORD;
bestCount = NKEYWORD*NKEYWORD;
for(i=NKEYWORD/2; i<=2*NKEYWORD; i++){
for(j=0; j<i; j++) aHash[j] = 0;
for(j=0; j<NKEYWORD; j++){
h = aKeywordTable[j].hash % i;
aHash[h] *= 2;
aHash[h]++;
}
for(j=count=0; j<i; j++) count += aHash[j];
if( count<bestCount ){
bestCount = count;
bestSize = i;
}
}
/* Compute the hash */
for(i=0; i<bestSize; i++) aHash[i] = 0;
for(i=0; i<NKEYWORD; i++){
h = aKeywordTable[i].hash % bestSize;
aKeywordTable[i].iNext = aHash[h];
aHash[h] = i+1;
}
/* Begin generating code */
printf("%s", zHdr);
printf("/* Hash score: %d */\n", bestCount);
printf("static int keywordCode(const char *z, int n){\n");
printf(" static const char zText[%d] =\n", nChar+1);
for(i=j=0; i<NKEYWORD; i++){
Keyword *p = &aKeywordTable[i];
if( p->substrId ) continue;
if( j==0 ) printf(" \"");
printf("%s", p->zName);
j += p->len;
if( j>60 ){
printf("\"\n");
j = 0;
}
}
printf("%s;\n", j>0 ? "\"" : " ");
printf(" static const unsigned char aHash[%d] = {\n", bestSize);
for(i=j=0; i<bestSize; i++){
if( j==0 ) printf(" ");
printf(" %3d,", aHash[i]);
j++;
if( j>12 ){
printf("\n");
j = 0;
}
}
printf("%s };\n", j==0 ? "" : "\n");
printf(" static const unsigned char aNext[%d] = {\n", NKEYWORD);
for(i=j=0; i<NKEYWORD; i++){
if( j==0 ) printf(" ");
printf(" %3d,", aKeywordTable[i].iNext);
j++;
if( j>12 ){
printf("\n");
j = 0;
}
}
printf("%s };\n", j==0 ? "" : "\n");
printf(" static const unsigned char aLen[%d] = {\n", NKEYWORD);
for(i=j=0; i<NKEYWORD; i++){
if( j==0 ) printf(" ");
printf(" %3d,", aKeywordTable[i].len+aKeywordTable[i].prefix);
j++;
if( j>12 ){
printf("\n");
j = 0;
}
}
printf("%s };\n", j==0 ? "" : "\n");
printf(" static const unsigned short int aOffset[%d] = {\n", NKEYWORD);
for(i=j=0; i<NKEYWORD; i++){
if( j==0 ) printf(" ");
printf(" %3d,", aKeywordTable[i].offset);
j++;
if( j>12 ){
printf("\n");
j = 0;
}
}
printf("%s };\n", j==0 ? "" : "\n");
printf(" static const unsigned char aCode[%d] = {\n", NKEYWORD);
for(i=j=0; i<NKEYWORD; i++){
char *zToken = aKeywordTable[i].zTokenType;
if( j==0 ) printf(" ");
printf("%s,%*s", zToken, (int)(14-strlen(zToken)), "");
j++;
if( j>=5 ){
printf("\n");
j = 0;
}
}
printf("%s };\n", j==0 ? "" : "\n");
printf(" int h, i;\n");
printf(" if( n<2 ) return TK_ID;\n");
printf(" h = ((charMap(z[0])*4) ^\n"
" (charMap(z[n-1])*3) ^\n"
" n) %% %d;\n", bestSize);
printf(" for(i=((int)aHash[h])-1; i>=0; i=((int)aNext[i])-1){\n");
printf(" if( aLen[i]==n &&"
" sqlite3StrNICmp(&zText[aOffset[i]],z,n)==0 ){\n");
printf(" return aCode[i];\n");
printf(" }\n");
printf(" }\n");
printf(" return TK_ID;\n");
printf("}\n");
printf("int sqlite3KeywordCode(const unsigned char *z, int n){\n");
printf(" return keywordCode((char*)z, n);\n");
printf("}\n");
return 0;
}