int ReadHelpFile(int index)
{
FILE* fptr;
unsigned long offset;
int complen, uncomplen;
int c, result, read = 0, numpages;
unsigned char *CompData, *UncompData, *pos;
/* Free any memory from a previous help file */
FreeHelpSysData();
/* Return if the help file was corrupted. */
if (HelpFile[0] == '\0')
return HELPREADERROR;
/* Get the number of pages in the help file, and check wether
the asked page exists. */
numpages = GetNumberOfHelpPages();
if ((numpages == 0) || (index >= numpages))
{
LogPrint("Invalid index");
return HELPREADERROR;
}
/* Get the positions in the help file where to read
the file, the number of bytes to read and the number of
bytes to reserve as the output. */
if (!GetIndexInformation(index, &offset, &complen, &uncomplen))
{
LogPrint("Invalid index");
return HELPREADERROR;
}
/* Try allocating the memory required. */
CompData = (unsigned char*) malloc(complen);
if (!CompData)
return HELPMEMINSUFFICIENT;
UncompData = (unsigned char*) malloc(uncomplen);
if (!UncompData)
{
free(CompData);
return HELPMEMINSUFFICIENT;
}
/* Read the file. */
if ((fptr = fopen(HelpFile, "rb")) != NULL)
{
fseek(fptr, offset, SEEK_SET);
pos = CompData;
while ((c = fgetc(fptr)) != EOF)
{
*pos++ = (char) c;
read++;
if (read == complen) break;
}
fclose(fptr);
}
else
{
free(CompData);
free(UncompData);
return HELPREADERROR;
}
if (read != complen)
{
free(CompData);
free(UncompData);
return HELPREADERROR;
}
UncompressBuffer(CompData, UncompData, complen, uncomplen);
free(CompData); /* Don't need the compressed data any more. */
result = ParseHelpFile((char*) UncompData, uncomplen);
free(UncompData); /* Don't need the raw text data any more. */
return result;
}
void TOperandString::Uncompress(TOperandString *op, Buffer *buf)
{
Buffer read_buf(op->GetData(), op->GetDataLength());
UncompressBuffer(&read_buf, buf);
}
