/************************************************************************/
/* Shared library routine for parsing .csv files                        */
/* Scott Auge sauge@amduus.com scott_auge@yahoo.com                     */
/************************************************************************/

char *RCS = "$Header: /home/sauge/code/C/importer/prsimport.c,v 1.7 2004/11/20 10:46:35 sauge Exp sauge $";

/* Comment out to turn off or use -DDEBUG in compiler invocation */
/* This should be compiled with -shared on gcc or what ever      */
/* creates a shared memory executable on your operating system.  */

/* #define DEBUG */

#include <string.h>
#include "prsimport.h"

#ifdef DEBUG
#include <stdio.h>
#endif

/************************************************************************/
/* Given a line from a .csv file, determine how many entries there are. */
/* Strings are contained in " and "                                     */
/* Quotes are double quoted as in """" is for a string "                */
/* Numbers are contained without " and "                                */
/* Warning: If the data size in the column for the given Line is        */
/* greater than the space allocated in Junk, this routine will          */
/* wash out!                                                            */
/************************************************************************/

int NumColumns (char *Line, char *Junk) {

  int iNumColumns = 0;
  
  /* Loop GetColumn incrementing column number till it complains */

  while(1) {
    if (GetColumn(Line, iNumColumns, Junk) == 0) 
      iNumColumns++;
    else 
      break;
  }

  return iNumColumns; 

} /* int NumColumns () */

/************************************************************************/
/* Given a line and column number, return the text in that line.  Fun-  */
/* ction returns the error or no error.                                 */
/* You must allocate the space for Value yourself.                      */
/************************************************************************/

int GetColumn (char *cpLine, int iColumn, char *cpValue) {

  typedef enum {FALSE = 0, TRUE = 1} bool;

  int iCurColumn = 0, iCurLinePos = 0, iCurValuePos = 0;
  char cCurChar;
  bool InString = FALSE;
  int iLineLen = strlen(cpLine);

#ifdef DEBUG
printf("1:iLineLen=%i\n", iLineLen);
#endif

  /* Find the column we want */

  while (1) {

    /* If we are on the column we want, bail outta here */
    if (iCurColumn == iColumn) break;

    /* Ran out of string - return impossible column number error */
    if (iCurLinePos > iLineLen) return -1;

    /* Grab a character from line and move forward for the next one */
    cCurChar = *(cpLine + iCurLinePos);
    iCurLinePos++;

#ifdef DEBUG
printf("2:cCurChar = %c, iCurLinePos=%i\n", cCurChar, iCurLinePos);
#endif

    /* If we got a ", we need to know if we are in a string, or if */
    /* we are working a "" which is a " in the string.             */
    /* If we are working a "" then skip over it.  If not, then we  */
    /* are in a string delimiter.  Toggle the InString flag.       */
	
	if (cCurChar == '"' && *(cpLine + iCurLinePos) == '"') 
	  iCurLinePos++;
	else
	  if (cCurChar == '"') {
	    InString = InString == FALSE ? TRUE : FALSE;
		continue;
	  }

    /* If we got a comma and we ain't in a string, then we found */
    /* a new column!                                             */

    if (cCurChar == ',' && InString == FALSE) iCurColumn++;

  } /* while () */

  /* Start pulling out the data we want */

  while (1) {
  
    /* Ran out of string - return impossible column number error */
    if (iCurLinePos >= iLineLen) return 0;

    /* Grab a character from line and move forward for the next one */
    cCurChar = *(cpLine + iCurLinePos);
    iCurLinePos++;

#ifdef DEBUG
printf("2:cCurChar = %c, iCurLinePos=%i\n", cCurChar, iCurLinePos);
#endif

    /* If we got a ", we need to know if we are in a string, or if */
    /* we are working a "" which is a " in the string.             */
    /* If we are working a "" then skip over it.  If not, then we  */
    /* are in a string delimiter.  Toggle the InString flag.       */
	
	if (cCurChar == '"' && *(cpLine + iCurLinePos) == '"') 
	  iCurLinePos++;
	else
	  if (cCurChar == '"') {
	    InString = InString == FALSE ? TRUE : FALSE;
		continue;
	  }
		
    /* If we got a comma and we ain't in a string, then we found */
    /* a new column!  We are done!                               */

    if (cCurChar == ',' && InString == FALSE) break;

    *(cpValue + iCurValuePos) = cCurChar;
	iCurValuePos++;

  } /* while () */

  return 0;

} /* GetColumn () */

/************************************************************************/
/* Progress doesn't provide much to clean up memory once it has been    */
/* used.  Even unallocating and re-allocating doesn't work to clean     */
/* char strings.  Run the memptr's through this to clean em out.        */
/************************************************************************/

int ClearMem (char *M, int Size) {

  memset((char *)M, '\0', Size);

} /* ClearMem */