/* Read an arbitrarily long line of text from STREAM into LINEBUFFER.
* Consider lines to be terminated by DELIMITER.
* Keep the delimiter.
* Do not NUL-terminate; Therefore the stream can contain NUL bytes, and
* the length (including the delimiter) is returned in linebuffer->length.
* Return NULL when stream is empty or upon error.
* Otherwise, return LINEBUFFER.
*/
struct LineBuffer *readlinebuffer(struct LineBuffer *linebuffer, MY_FILE *stream, char delimiter)
{
int c;
char *buffer = linebuffer->buffer;
char *p = linebuffer->buffer;
char *end = buffer + linebuffer->size;
if(my_feof(stream)) return NULL;
do
{
c = my_fgetc(stream);
if(c == EOF)
{
// Return NULL when stream is empty or upon error
if(p == buffer || my_ferror(stream)) return NULL;
// append DELIMITER if it's the last line of a file that ends in a character other than DELIMITER.
if(p[-1] != delimiter) c = delimiter;
}
// Check if we need to allocate more space
if(p == end)
{
size_t oldsize = linebuffer->size;
linebuffer->size += BUFF_SIZE_INC;
buffer = realloc(buffer, linebuffer->size);
p = buffer + oldsize;
linebuffer->buffer = buffer;
end = buffer + linebuffer->size;
}
*p++ = c;
}
while(c != delimiter);
linebuffer->length = p - buffer;
return linebuffer;
}
int encfile(struct my_FILE* fin, struct aes *ctx)
{ unsigned char inbuf[16], outbuf[16];
long int flen;
unsigned long i=0, l=0;
fillrand(outbuf, 16); /* set an IV for CBC mode */
flen = fin->size;
// fseek(fin, 0, SEEK_END); /* get the length of the file */
// fgetpos(fin, (fpos_t*)&flen); /* and then reset to start */
// fseek(fin, 0, SEEK_SET);
// fwrite(outbuf, 1, 16, fout); /* write the IV to the output */
fillrand(inbuf, 1); /* make top 4 bits of a byte random */
l = 15; /* and store the length of the last */
/* block in the lower 4 bits */
inbuf[0] = ((char)flen & 15) | (inbuf[0] & ~15);
_Pragma( "loopbound min 1961 max 1961" )
while(!my_feof(fin)) /* loop to encrypt the input file */
{ /* input 1st 16 bytes to buf[1..16] */
i = my_fread(inbuf + 16 - l, 1, l, fin); /* on 1st round byte[0] */
/* is the length code */
if(i < l) break; /* if end of the input file reached */
_Pragma( "loopbound min 16 max 16" )
for(i = 0; i < 16; ++i) /* xor in previous cipher text */
inbuf[i] ^= outbuf[i];
encrypt(inbuf, outbuf, ctx); /* and do the encryption */
// if(fwrite(outbuf, 1, 16, fout) != 16) {
// printf("Error writing to output file: %s\n", fn);
// return -7;
// }
/* in all but first round read 16 */
l = 16; /* bytes into the buffer */
}
/* except for files of length less than two blocks we now have one */
/* byte from the previous block and 'i' bytes from the current one */
/* to encrypt and 15 - i empty buffer positions. For files of less */
/* than two blocks (0 or 1) we have i + 1 bytes and 14 - i empty */
/* buffer position to set to zero since the 'count' byte is extra */
if(l == 15) /* adjust for extra byte in the */
++i; /* in the first block */
if(i) /* if bytes remain to be output */
{
_Pragma( "loopbound min 6 max 6" )
while(i < 16) /* clear empty buffer positions */
inbuf[i++] = 0;
_Pragma( "loopbound min 16 max 16" )
for(i = 0; i < 16; ++i) /* xor in previous cipher text */
inbuf[i] ^= outbuf[i];
encrypt(inbuf, outbuf, ctx); /* encrypt and output it */
// if(fwrite(outbuf, 1, 16, fout) != 16) {
// printf("Error writing to output file: %s\n", fn);
// return -8;
// }
}
return 0;
}
