diff options
Diffstat (limited to 'src/libs/sqlite2/table.c')
-rw-r--r-- | src/libs/sqlite2/table.c | 203 |
1 files changed, 203 insertions, 0 deletions
diff --git a/src/libs/sqlite2/table.c b/src/libs/sqlite2/table.c new file mode 100644 index 00000000..48c852d4 --- /dev/null +++ b/src/libs/sqlite2/table.c @@ -0,0 +1,203 @@ +/* +** 2001 September 15 +** +** 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. +** +************************************************************************* +** This file contains the sqlite_get_table() and sqlite_free_table() +** interface routines. These are just wrappers around the main +** interface routine of sqlite_exec(). +** +** These routines are in a separate files so that they will not be linked +** if they are not used. +*/ +#include <stdlib.h> +#include <string.h> +#include "sqliteInt.h" + +/* +** This structure is used to pass data from sqlite_get_table() through +** to the callback function is uses to build the result. +*/ +typedef struct TabResult { + char **azResult; + char *zErrMsg; + int nResult; + int nAlloc; + int nRow; + int nColumn; + long nData; + int rc; +} TabResult; + +/* +** This routine is called once for each row in the result table. Its job +** is to fill in the TabResult structure appropriately, allocating new +** memory as necessary. +*/ +static int sqlite_get_table_cb(void *pArg, int nCol, char **argv, char **colv){ + TabResult *p = (TabResult*)pArg; + int need; + int i; + char *z; + + /* Make sure there is enough space in p->azResult to hold everything + ** we need to remember from this invocation of the callback. + */ + if( p->nRow==0 && argv!=0 ){ + need = nCol*2; + }else{ + need = nCol; + } + if( p->nData + need >= p->nAlloc ){ + char **azNew; + p->nAlloc = p->nAlloc*2 + need + 1; + azNew = realloc( p->azResult, sizeof(char*)*p->nAlloc ); + if( azNew==0 ){ + p->rc = SQLITE_NOMEM; + return 1; + } + p->azResult = azNew; + } + + /* If this is the first row, then generate an extra row containing + ** the names of all columns. + */ + if( p->nRow==0 ){ + p->nColumn = nCol; + for(i=0; i<nCol; i++){ + if( colv[i]==0 ){ + z = 0; + }else{ + z = malloc( strlen(colv[i])+1 ); + if( z==0 ){ + p->rc = SQLITE_NOMEM; + return 1; + } + strcpy(z, colv[i]); + } + p->azResult[p->nData++] = z; + } + }else if( p->nColumn!=nCol ){ + sqliteSetString(&p->zErrMsg, + "sqlite_get_table() called with two or more incompatible queries", + (char*)0); + p->rc = SQLITE_ERROR; + return 1; + } + + /* Copy over the row data + */ + if( argv!=0 ){ + for(i=0; i<nCol; i++){ + if( argv[i]==0 ){ + z = 0; + }else{ + z = malloc( strlen(argv[i])+1 ); + if( z==0 ){ + p->rc = SQLITE_NOMEM; + return 1; + } + strcpy(z, argv[i]); + } + p->azResult[p->nData++] = z; + } + p->nRow++; + } + return 0; +} + +/* +** Query the database. But instead of invoking a callback for each row, +** malloc() for space to hold the result and return the entire results +** at the conclusion of the call. +** +** The result that is written to ***pazResult is held in memory obtained +** from malloc(). But the caller cannot free this memory directly. +** Instead, the entire table should be passed to sqlite_free_table() when +** the calling procedure is finished using it. +*/ +int sqlite_get_table( + sqlite *db, /* The database on which the SQL executes */ + const char *zSql, /* The SQL to be executed */ + char ***pazResult, /* Write the result table here */ + int *pnRow, /* Write the number of rows in the result here */ + int *pnColumn, /* Write the number of columns of result here */ + char **pzErrMsg /* Write error messages here */ +){ + int rc; + TabResult res; + if( pazResult==0 ){ return SQLITE_ERROR; } + *pazResult = 0; + if( pnColumn ) *pnColumn = 0; + if( pnRow ) *pnRow = 0; + res.zErrMsg = 0; + res.nResult = 0; + res.nRow = 0; + res.nColumn = 0; + res.nData = 1; + res.nAlloc = 20; + res.rc = SQLITE_OK; + res.azResult = malloc( sizeof(char*)*res.nAlloc ); + if( res.azResult==0 ){ + return SQLITE_NOMEM; + } + res.azResult[0] = 0; + rc = sqlite_exec(db, zSql, sqlite_get_table_cb, &res, pzErrMsg); + if( res.azResult ){ + res.azResult[0] = (char*)res.nData; + } + if( rc==SQLITE_ABORT ){ + sqlite_free_table(&res.azResult[1]); + if( res.zErrMsg ){ + if( pzErrMsg ){ + free(*pzErrMsg); + *pzErrMsg = res.zErrMsg; + sqliteStrRealloc(pzErrMsg); + }else{ + sqliteFree(res.zErrMsg); + } + } + return res.rc; + } + sqliteFree(res.zErrMsg); + if( rc!=SQLITE_OK ){ + sqlite_free_table(&res.azResult[1]); + return rc; + } + if( res.nAlloc>res.nData ){ + char **azNew; + azNew = realloc( res.azResult, sizeof(char*)*(res.nData+1) ); + if( azNew==0 ){ + sqlite_free_table(&res.azResult[1]); + return SQLITE_NOMEM; + } + res.nAlloc = res.nData+1; + res.azResult = azNew; + } + *pazResult = &res.azResult[1]; + if( pnColumn ) *pnColumn = res.nColumn; + if( pnRow ) *pnRow = res.nRow; + return rc; +} + +/* +** This routine frees the space the sqlite_get_table() malloced. +*/ +void sqlite_free_table( + char **azResult /* Result returned from from sqlite_get_table() */ +){ + if( azResult ){ + int i, n; + azResult--; + if( azResult==0 ) return; + n = (int)(long)azResult[0]; + for(i=1; i<n; i++){ if( azResult[i] ) free(azResult[i]); } + free(azResult); + } +} |