printf.c

sqlite数据库管理系统开放源码

        break;
      }
      case etSRCLIST: {
        SrcList *pSrc = va_arg(ap, SrcList*);
        int k = va_arg(ap, int);
        struct SrcList_item *pItem = &pSrc->a[k];
        assert( k>=0 && k<pSrc->nSrc );
        if( pItem->zDatabase && pItem->zDatabase[0] ){
          (*func)(arg, pItem->zDatabase, strlen(pItem->zDatabase));
          (*func)(arg, ".", 1);
        }
        (*func)(arg, pItem->zName, strlen(pItem->zName));
        length = width = 0;
        break;
      }
      case etERROR:
        buf[0] = '%';
        buf[1] = c;
        errorflag = 0;
        idx = 1+(c!=0);
        (*func)(arg,"%",idx);
        count += idx;
        if( c==0 ) fmt--;
        break;
    }/* End switch over the format type */
    /*
    ** The text of the conversion is pointed to by "bufpt" and is
    ** "length" characters long.  The field width is "width".  Do
    ** the output.
    */
    if( !flag_leftjustify ){
      register int nspace;
      nspace = width-length;
      if( nspace>0 ){
        count += nspace;
        while( nspace>=etSPACESIZE ){
          (*func)(arg,spaces,etSPACESIZE);
          nspace -= etSPACESIZE;
        }
        if( nspace>0 ) (*func)(arg,spaces,nspace);
      }
    }
    if( length>0 ){
      (*func)(arg,bufpt,length);
      count += length;
    }
    if( flag_leftjustify ){
      register int nspace;
      nspace = width-length;
      if( nspace>0 ){
        count += nspace;
        while( nspace>=etSPACESIZE ){
          (*func)(arg,spaces,etSPACESIZE);
          nspace -= etSPACESIZE;
        }
        if( nspace>0 ) (*func)(arg,spaces,nspace);
      }
    }
    if( zExtra ){
      sqliteFree(zExtra);
    }
  }/* End for loop over the format string */
  return errorflag ? -1 : count;
} /* End of function */


/* This structure is used to store state information about the
** write to memory that is currently in progress.
*/
struct sgMprintf {
  char *zBase;     /* A base allocation */
  char *zText;     /* The string collected so far */
  int  nChar;      /* Length of the string so far */
  int  nTotal;     /* Output size if unconstrained */
  int  nAlloc;     /* Amount of space allocated in zText */
  void *(*xRealloc)(void*,int);  /* Function used to realloc memory */
};

/* 
** This function implements the callback from vxprintf. 
**
** This routine add nNewChar characters of text in zNewText to
** the sgMprintf structure pointed to by "arg".
*/
static void mout(void *arg, const char *zNewText, int nNewChar){
  struct sgMprintf *pM = (struct sgMprintf*)arg;
  pM->nTotal += nNewChar;
  if( pM->nChar + nNewChar + 1 > pM->nAlloc ){
    if( pM->xRealloc==0 ){
      nNewChar =  pM->nAlloc - pM->nChar - 1;
    }else{
      pM->nAlloc = pM->nChar + nNewChar*2 + 1;
      if( pM->zText==pM->zBase ){
        pM->zText = pM->xRealloc(0, pM->nAlloc);
        if( pM->zText && pM->nChar ){
          memcpy(pM->zText, pM->zBase, pM->nChar);
        }
      }else{
        pM->zText = pM->xRealloc(pM->zText, pM->nAlloc);
      }
    }
  }
  if( pM->zText ){
    if( nNewChar>0 ){
      memcpy(&pM->zText[pM->nChar], zNewText, nNewChar);
      pM->nChar += nNewChar;
    }
    pM->zText[pM->nChar] = 0;
  }
}

/*
** This routine is a wrapper around xprintf() that invokes mout() as
** the consumer.  
*/
static char *base_vprintf(
  void *(*xRealloc)(void*,int),   /* Routine to realloc memory. May be NULL */
  int useInternal,                /* Use internal %-conversions if true */
  char *zInitBuf,                 /* Initially write here, before mallocing */
  int nInitBuf,                   /* Size of zInitBuf[] */
  const char *zFormat,            /* format string */
  va_list ap                      /* arguments */
){
  struct sgMprintf sM;
  sM.zBase = sM.zText = zInitBuf;
  sM.nChar = sM.nTotal = 0;
  sM.nAlloc = nInitBuf;
  sM.xRealloc = xRealloc;
  vxprintf(mout, &sM, useInternal, zFormat, ap);
  if( xRealloc ){
    if( sM.zText==sM.zBase ){
      sM.zText = xRealloc(0, sM.nChar+1);
      memcpy(sM.zText, sM.zBase, sM.nChar+1);
    }else if( sM.nAlloc>sM.nChar+10 ){
      sM.zText = xRealloc(sM.zText, sM.nChar+1);
    }
  }
  return sM.zText;
}

/*
** Realloc that is a real function, not a macro.
*/
static void *printf_realloc(void *old, int size){
  return sqliteRealloc(old,size);
}

/*
** Print into memory obtained from sqliteMalloc().  Use the internal
** %-conversion extensions.
*/
char *sqliteVMPrintf(const char *zFormat, va_list ap){
  char zBase[1000];
  return base_vprintf(printf_realloc, 1, zBase, sizeof(zBase), zFormat, ap);
}

/*
** Print into memory obtained from sqliteMalloc().  Use the internal
** %-conversion extensions.
*/
char *sqliteMPrintf(const char *zFormat, ...){
  va_list ap;
  char *z;
  char zBase[1000];
  va_start(ap, zFormat);
  z = base_vprintf(printf_realloc, 1, zBase, sizeof(zBase), zFormat, ap);
  va_end(ap);
  return z;
}

/*
** Print into memory obtained from malloc().  Do not use the internal
** %-conversion extensions.  This routine is for use by external users.
*/
char *sqlite_mprintf(const char *zFormat, ...){
  va_list ap;
  char *z;
  char zBuf[200];

  va_start(ap,zFormat);
  z = base_vprintf((void*(*)(void*,int))realloc, 0, 
                   zBuf, sizeof(zBuf), zFormat, ap);
  va_end(ap);
  return z;
}

/* This is the varargs version of sqlite_mprintf.  
*/
char *sqlite_vmprintf(const char *zFormat, va_list ap){
  char zBuf[200];
  return base_vprintf((void*(*)(void*,int))realloc, 0,
                      zBuf, sizeof(zBuf), zFormat, ap);
}

/*
** sqlite_snprintf() works like snprintf() except that it ignores the
** current locale settings.  This is important for SQLite because we
** are not able to use a "," as the decimal point in place of "." as
** specified by some locales.
*/
char *sqlite_snprintf(int n, char *zBuf, const char *zFormat, ...){
  char *z;
  va_list ap;

  va_start(ap,zFormat);
  z = base_vprintf(0, 0, zBuf, n, zFormat, ap);
  va_end(ap);
  return z;
}

/*
** The following four routines implement the varargs versions of the
** sqlite_exec() and sqlite_get_table() interfaces.  See the sqlite.h
** header files for a more detailed description of how these interfaces
** work.
**
** These routines are all just simple wrappers.
*/
int sqlite_exec_printf(
  sqlite *db,                   /* An open database */
  const char *sqlFormat,        /* printf-style format string for the SQL */
  sqlite_callback xCallback,    /* Callback function */
  void *pArg,                   /* 1st argument to callback function */
  char **errmsg,                /* Error msg written here */
  ...                           /* Arguments to the format string. */
){
  va_list ap;
  int rc;

  va_start(ap, errmsg);
  rc = sqlite_exec_vprintf(db, sqlFormat, xCallback, pArg, errmsg, ap);
  va_end(ap);
  return rc;
}
int sqlite_exec_vprintf(
  sqlite *db,                   /* An open database */
  const char *sqlFormat,        /* printf-style format string for the SQL */
  sqlite_callback xCallback,    /* Callback function */
  void *pArg,                   /* 1st argument to callback function */
  char **errmsg,                /* Error msg written here */
  va_list ap                    /* Arguments to the format string. */
){
  char *zSql;
  int rc;

  zSql = sqlite_vmprintf(sqlFormat, ap);
  rc = sqlite_exec(db, zSql, xCallback, pArg, errmsg);
  free(zSql);
  return rc;
}
int sqlite_get_table_printf(
  sqlite *db,            /* An open database */
  const char *sqlFormat, /* printf-style format string for the SQL */
  char ***resultp,       /* Result written to a char *[]  that this points to */
  int *nrow,             /* Number of result rows written here */
  int *ncol,             /* Number of result columns written here */
  char **errmsg,         /* Error msg written here */
  ...                    /* Arguments to the format string */
){
  va_list ap;
  int rc;

  va_start(ap, errmsg);
  rc = sqlite_get_table_vprintf(db, sqlFormat, resultp, nrow, ncol, errmsg, ap);
  va_end(ap);
  return rc;
}
int sqlite_get_table_vprintf(
  sqlite *db,            /* An open database */
  const char *sqlFormat, /* printf-style format string for the SQL */
  char ***resultp,       /* Result written to a char *[]  that this points to */
  int *nrow,             /* Number of result rows written here */
  int *ncolumn,          /* Number of result columns written here */
  char **errmsg,         /* Error msg written here */
  va_list ap             /* Arguments to the format string */
){
  char *zSql;
  int rc;

  zSql = sqlite_vmprintf(sqlFormat, ap);
  rc = sqlite_get_table(db, zSql, resultp, nrow, ncolumn, errmsg);
  free(zSql);
  return rc;
}