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/*
* CSVParse.C * * CSV Parsing functions * * Copyright 1997 Microsoft Corporation. All Rights Reserved. */#include <windows.h>
#include <wab.h>
#include <wabguid.h>
#include <wabdbg.h>
#include "dbgutil.h"
#include <shlwapi.h>
#define CR_CHAR 0x0d
#define LF_CHAR 0x0a
#define CCH_READ_BUFFER 256
#define NUM_ITEM_SLOTS 32
/***************************************************************************
Name : ReadCSVChar
Purpose : Reads a single char from a file
Parameters: hFile = file handle pcbBuffer = pointer to size of buffer lppBuffer = pointer to pointer to buffer lppRead = pointer to pointer to next location to use
Returns : -1 = Out of memory 0 = End of file 1 = Char successfully read
Comment : Dynamically grows *lppBuffer as necessary
***************************************************************************/int ReadCSVChar(HANDLE hFile, int *pcbBuffer, PUCHAR *lppBuffer, PUCHAR *lppRead){ int cbOffset; ULONG cbReadFile; PUCHAR lpBuffer;
cbOffset = (int) (*lppRead - *lppBuffer); if (cbOffset >= *pcbBuffer) { // Buffer is too small. Reallocate!
*pcbBuffer += CCH_READ_BUFFER; if (! (lpBuffer = LocalReAlloc(*lppBuffer, *pcbBuffer, LMEM_MOVEABLE | LMEM_ZEROINIT))) { DebugTrace("LocalReAlloc(%u) -> %u\n", *pcbBuffer, GetLastError()); return(-1); } *lppBuffer = lpBuffer; *lppRead = *lppBuffer + cbOffset; }
// 1 character at a time
if (ReadFile(hFile, *lppRead, 1, &cbReadFile, NULL) && cbReadFile) return(1); return(0);}
/***************************************************************************
Name : ReadCSVItem
Purpose : Reads an item from a CSV file
Parameters: hFile = file handle pcbBuffer = pointer to size of buffer lppBuffer = pointer to pointer to buffer szSep = current separator string
Returns : -1 = Out of memory 0 = Item read in, and none left 1 = Item read in, more items left
Comment : CSV special characters are '"', szSep, CR and LF.
Rules for quotes: 1. If an item starts with a '"', then the item is quoted and must end with a '"'. 2. Any '"' characters found in a non-quoted string will not be treated specially. Technically, there should not be quotes in a non-quoted string, but we have to do something if we find one. 3. A quoted item ends with: a) quote szSep b) quote newline or, c) quote <EOF> 4. Two quotes together in a quoted string are translated into a single quote.
***************************************************************************/int ReadCSVItem(HANDLE hFile, int *pcbBuffer, PUCHAR *lppBuffer, LPTSTR szSep){ BOOL fQuoted, fDone, fFoundSepCh; int cbReadFile; PUCHAR lpRead, szSepT;
// This function is always called with one character already read
lpRead = *lppBuffer; if (*lpRead == '"') { fQuoted = TRUE; cbReadFile = ReadCSVChar(hFile, pcbBuffer, lppBuffer, &lpRead); } else { fQuoted = FALSE; cbReadFile = 1; } szSepT = szSep; fDone = FALSE; do { if (cbReadFile <= 0) { // End of file means end of item
if (cbReadFile == 0) *lpRead = '\0'; break; } fFoundSepCh = FALSE; switch (*lpRead) { case CR_CHAR: case LF_CHAR: if (!fQuoted) { // End of line and item
*lpRead = '\0'; cbReadFile = 0; fDone = TRUE; } break; case '"': if (fQuoted) { // See if the next character is a quote, CR, or LF
lpRead++; cbReadFile = ReadCSVChar(hFile, pcbBuffer, lppBuffer, &lpRead); if ((cbReadFile <= 0) || (*lpRead == '"') || (*lpRead == CR_CHAR) || (*lpRead == LF_CHAR)) { if ((cbReadFile <= 0) || (*lpRead != '"')) { if (cbReadFile >= 0) { // End of file, or CR or LF
*(lpRead - 1) = '\0'; cbReadFile = 0; } // else out of memory
fDone = TRUE; } else { // Embedded quote - get rid of one
lpRead--; } break; } // We have read another character, and it is not a quote, CR, or LF
// Two possibilities:
// 1) Separator
// 2) Something else - this is an error condition
szSepT = szSep; while ((cbReadFile > 0) && (*szSepT != '\0') && (*lpRead == *szSepT)) { szSepT++; if (*szSepT != '\0') { lpRead++; cbReadFile = ReadCSVChar(hFile, pcbBuffer, lppBuffer, &lpRead); } } if ((cbReadFile <= 0) || (*szSepT == '\0')) { if (cbReadFile >= 0) { // If cbReadFile is zero, we hit the end of file
// before finding the complete separator. In this
// case, we simply take every character we have
// read, including the second quote, and use that
// as the item.
//
// Otherwise, we found the complete separator.
if (cbReadFile > 0) lpRead -= lstrlen(szSep); *lpRead = '\0'; } fDone = TRUE; } else { // We found a second quote, but it was not followed by a
// separator. In this case, we keep reading as if we are
// in an unquoted string.
fQuoted = FALSE; } } break; default: if (!fQuoted) { if (*lpRead == *szSepT) { szSepT++; if (*szSepT == '\0') { // End of separator, thus end of item
lpRead -= (lstrlen(szSep) - 1); *lpRead = '\0'; fDone = TRUE; } else fFoundSepCh = TRUE; } } break; } if (!fDone) { if (!fFoundSepCh) szSepT = szSep; lpRead++; cbReadFile = ReadCSVChar(hFile, pcbBuffer, lppBuffer, &lpRead); } } while (!fDone); return(cbReadFile);}
/***************************************************************************
Name : InsertItem
Purpose : Takes an item read from the file and inserts it into the array
Parameters: iItem = array index to insert pcItemSlots = number of currently allocated elements cGrow = number of items to grow the array by, if necessary prgItemSlots = pointer to the actual array lpBuffer = string to insert
Returns : TRUE = item successfully inserted FALSE = out of memory
***************************************************************************/BOOL InsertItem(int iItem, int *pcItemSlots, int cGrow, PUCHAR **prgItemSlots, PUCHAR lpBuffer){ PUCHAR *rgItemSlotsNew, lpItem;
// Make sure there's room, first
if (iItem >= *pcItemSlots) { // Array is too small. Reallocate!
*pcItemSlots += cGrow; rgItemSlotsNew = LocalReAlloc(*prgItemSlots, *pcItemSlots * sizeof(PUCHAR), LMEM_MOVEABLE | LMEM_ZEROINIT); if (!rgItemSlotsNew) { DebugTrace("LocalReAlloc(%u) -> %u\n", *pcItemSlots * sizeof(PUCHAR), GetLastError()); return(FALSE); } *prgItemSlots = rgItemSlotsNew; }
lpItem = LocalAlloc(LPTR, lstrlen(lpBuffer) + 1); if (!lpItem) { DebugTrace("LocalAlloc(%u) -> %u\n", lstrlen(lpBuffer) + 1, GetLastError()); return(FALSE); }
StrCpyN(lpItem, lpBuffer, lstrlen(lpBuffer) + 1); (*prgItemSlots)[iItem] = lpItem;
return(TRUE);}
/***************************************************************************
Name : ReadCSVLine x
Purpose : Reads a line from a CSV file with fixups for special characters
Parameters: hFile = file handle szSep = list separator of the current regional settings lpcItems -> Returned number of items lprgItems -> Returned array of item strings. Caller is responsible for LocalFree'ing each string pointer and this array pointer.
Returns : HRESULT
Comment : Calls the above helper functions to do most of the work.
***************************************************************************/HRESULT ReadCSVLine(HANDLE hFile, LPTSTR szSep, ULONG * lpcItems, PUCHAR ** lpprgItems) { HRESULT hResult = hrSuccess; register ULONG i; PUCHAR lpBuffer = NULL, lpRead, lpItem; ULONG cbBuffer = 0; int cbReadFile = -1; UCHAR chLastChar; ULONG iItem = 0; ULONG cItemSlots = 0; PUCHAR * rgItemSlots = NULL; LPTSTR szSepT;
// Start out with 1024 character buffer. Realloc as necesary.
cbBuffer = CCH_READ_BUFFER; if (! (lpRead = lpBuffer = LocalAlloc(LPTR, cbBuffer))) { DebugTrace("LocalAlloc(%u) -> %u\n", cbBuffer, GetLastError()); goto exit; }
// Start out with 32 item slots. Realloc as necesary.
cItemSlots = NUM_ITEM_SLOTS; if (! (rgItemSlots = LocalAlloc(LPTR, cItemSlots * sizeof(PUCHAR)))) { DebugTrace("LocalAlloc(%u) -> %u\n", cItemSlots * sizeof(PUCHAR), GetLastError()); goto exit; }
// Skip past leading CR/LF characters
do cbReadFile = ReadCSVChar(hFile, &cbBuffer, &lpBuffer, &lpRead); while((cbReadFile > 0) && ((*lpBuffer == CR_CHAR) || (*lpBuffer == LF_CHAR))); if (cbReadFile == 0) { // Nothing to return
DebugTrace("ReadFile -> EOF\n"); hResult = ResultFromScode(MAPI_E_NOT_FOUND); }
// Read items until end of line or EOF
while (cbReadFile > 0) { cbReadFile = ReadCSVItem(hFile, &cbBuffer, &lpBuffer, szSep); if (cbReadFile >= 0) { // Dup the item into the next array slot.
if (!InsertItem(iItem, &cItemSlots, cbReadFile ? NUM_ITEM_SLOTS : 1, &rgItemSlots, lpBuffer)) cbReadFile = -1; else iItem++;
if (cbReadFile > 0) { // More data to be read
lpRead = lpBuffer; cbReadFile = ReadCSVChar(hFile, &cbBuffer, &lpBuffer, &lpRead); } } }
exit: if (cbReadFile < 0) hResult = ResultFromScode(MAPI_E_NOT_ENOUGH_MEMORY);
if (lpBuffer) { LocalFree(lpBuffer); }
if (hResult) { // Clean up
if (rgItemSlots) { for (i = 0; i < iItem; i++) { if (rgItemSlots[i]) { LocalFree(rgItemSlots[i]); } } LocalFree(rgItemSlots); } *lpcItems = 0; *lpprgItems = NULL; } else { *lpcItems = iItem; // One based
*lpprgItems = rgItemSlots; } return(hResult);}
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